COMPRESSOR

Abstract

A compressor includes a rotary shaft, a front rotor including a front rotor surface, an intermediate wall portion including a first wall surface opposed to the front rotor surface in an axial direction, and a vane that is inserted into a vane groove formed in the intermediate wall portion and is moved in the axial direction with rotation of the front rotor. The vane includes a first vane end that is an end in the axial direction and contacts the front rotor surface. The first vane end is curved so as to be convex toward the front rotor surface and extends in the direction perpendicular to the axial direction. The front rotor surface includes a front curving surface curved in the axial direction so as to be displaced in the axial direction in accordance with its angular position.

Description

TECHNICAL FIELD

The present invention relates to a compressor.

BACKGROUND ART

Patent Document 1 describes a compressor including a rotary shaft, rotors rotated with rotation of the rotary shaft, a vane moving in the axial direction of the rotary shaft with rotation of the rotors, and compression chambers. In this compressor, fluid is compressed in the compression chamber by rotating the rotors.

This document describes, as a third embodiment, a rotor surface formed by a curved surface in which the position of a straight line extending in the radial direction continuously becomes low from an initial angle to a first angular position of the rotor, and continuously becomes high from the first angular position to the initial angle, and a vane including an end contacting the rotor surface.

In the above-described configuration, the vane is easily oscillated in the circumferential direction of the rotor about the part at which the rotor surface contacts the end of the vane and that extends in the radial direction.

PRIOR ART DOCUMENT

Patent Document

Patent Document 1: Japanese Laid-Open Patent Publication No. 51-97006

SUMMARY OF THE INVENTION

Problems that the Invention is to Solve

An object of the present invention is to provide a compressor that can suppress the oscillation of a vane in the circumferential direction of a rotor.

Means for Solving the Problems

To achieve the foregoing objective and in accordance with a first aspect, a compressor is provided that includes a rotary shaft, a rotor including a rotor surface formed into a ring-shape, and rotated with rotation of the rotary shaft, a cylindrical portion including an inner circumferential surface opposed to an outer circumferential surface of the rotor in a radial direction of the rotary shaft, and housing the rotor, a wall portion including a wall surface opposed to the rotor surface in an axial direction of the rotary shaft, a vane inserted into a vane groove formed in the wall portion, and moved in the axial direction with rotation of the rotor, and a compression chamber defined by the rotor surface, the wall surface, and the inner circumferential surface of the cylindrical portion. A volume change of the compression chamber is caused by the vane with rotation of the rotor such that suction and compression of fluid are performed. The vane includes a vane end that is an end in the axial direction and contacts the rotor surface. The vane end is curved so as to be convex toward the rotor surface and extends in a direction perpendicular to the axial direction. The rotor surface includes a curving surface curved in the axial direction. The curving surface is curved so as to be displaced in the axial direction in accordance with its angular position. The curving surface includes a concave surface curved in the axial direction so as to be concave toward the wall surface, and a convex surface curved in the axial direction so as to be convex toward the wall surface. The concave surface includes a concave surface radially inner end and a concave surface radially outer end as opposite ends in the radial direction. In the concave surface, a radius of curvature of the concave surface radially inner end in the axial direction is smaller than a radius of curvature of the concave surface radially outer end. The convex surface includes a convex surface radially inner end and a convex surface radially outer end as opposite ends in the radial direction. In the convex surface, a radius of curvature of the convex surface radially inner end in the axial direction is smaller than a radius of curvature of the convex surface radially outer end.

To achieve the foregoing objective and in accordance with a second aspect, a compressor is provided that includes a rotary shaft, a rotor including a rotor surface formed into a ring-shape and rotated with rotation of the rotary shaft, a cylindrical portion including an inner circumferential surface opposed to an outer circumferential surface of the rotor in a radial direction of the rotary shaft, and housing the rotor, a wall portion including a wall surface opposed to the rotor surface in an axial direction of the rotary shaft, a vane that is inserted into a vane groove formed in the wall portion, and is moved in the axial direction with rotation of the rotor, and a compression chamber defined by the rotor surface, the wall surface, and the inner circumferential surface of the cylindrical portion. Volume change of the compression chamber is caused by the vane with rotation of the rotor such that suction and compression of fluid are performed. The vane includes a vane end that is an end in the axial direction and contacts the rotor surface. The vane end is curved so as to be convex toward the rotor surface and extends in a direction perpendicular to the axial direction. The rotor surface includes a curving surface curved in the axial direction. The curving surface is curved so as to be displaced in the axial direction in accordance with its angular position. The curving surface includes a part in which a radius of curvature with respect to the axial direction differs in accordance with a position in the radial direction such that at least a part of a contact line between the curving surface and the vane end is curved in a circumferential direction of the rotor.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view showing an outline of a compressor.

FIG. 2 is an exploded perspective view of a main configuration.

FIG. 3 is an exploded perspective view of the main configuration seen from the opposite side from FIG. 2.

FIG. 4 is a partial enlarged view of FIG. 1.

FIG. 5 is a cross-sectional view taken along line 5-5 in FIG. 4 in a non-communicating state.

FIG. 6 is a cross-sectional view taken along line 5-5 in FIG. 4 in a communicating state.

FIG. 7 is a cross-sectional view schematically showing the contacting manner between the vane and the curving surfaces.

FIG. 8 is a graph showing the displacement in the axial direction in accordance with the angular position on the rotor surface.

FIG. 9 is a front view of the front rotor.

FIG. 10 is a front view of the rear rotor.

FIG. 11 is a cross-sectional view showing the peripheral structure of the rotors and the vane in a case where they are cut near an inflection point.

FIG. 12 is a schematic diagram showing a front contact line seen from the axial direction.

FIG. 13 is a schematic diagram showing a rear contact line seen from the axial direction.

FIG. 14A is a cross-sectional view showing the rotors and their surroundings.

FIG. 14B is a cross-sectional view showing the situation of the rotors and the vane in the state of FIG. 14A.

FIG. 15A is a cross-sectional view showing the rotors and their surroundings.

FIG. 15B is a cross-sectional view showing the situation of the rotors and the vane in the state of FIG. 15A.

FIG. 16 is a graph showing the volume change.

FIG. 17 is a schematic diagram showing a modification of a communication mechanism.

FIG. 18 is a schematic diagram showing the modification of the communication mechanism.

FIG. 19 is a cross-sectional view schematically showing a compressor of a modification.

FIG. 20 is a cross-sectional view schematically showing a vane of a modification.

FIG. 21 is a partially enlarged view of FIG. 20.

FIG. 22 is a cross-sectional view schematically showing a vane of a modification.

MODES FOR CARRYING OUT THE INVENTION

A compressor according to an embodiment will now be described with reference to the drawings. The compressor of the embodiment is mounted on and used in a vehicle. The compressor is used for a vehicle air-conditioner. The fluid to be compressed by the compressor is refrigerant including oil. FIGS. 1 and 4 show side views of a rotary shaft 12 and the rotors 60 and 80.

As shown in FIG. 1, a compressor 10 includes a housing 11, a rotary shaft 12, an electric motor 13, an inverter 14, a front cylinder 40, a rear cylinder 50, a front rotor 60 as a first rotor, and rear rotor 80 as a second rotor. The housing 11 has a generally tubular shape, and includes an inlet 11a through which a suction fluid is drawn in from the outside, and an outlet 11b from which the fluid is discharged. The rotary shaft 12, the electric motor 13, the inverter 14, the cylinders 40 and 50, and the rotors 60 and 80 are housed in the housing 11.

The housing 11 includes a front housing member 21, a rear housing member 22, and an inverter cover 23. The front housing member 21 has a tubular shape with a closed end, and is opened toward the rear housing member 22. The inlet 11a is provided at a position between an open end and the bottom in a side wall portion of the front housing member 21. However, the position of the inlet 11a is arbitrary. The rear housing member 22 has a tubular shape with a closed end, and is opened toward the front housing member 21. The outlet 11b is provided in a side surface of the bottom of the rear housing member 22. The position of the outlet 11b is arbitrary.

The front housing member 21 and the rear housing member 22 are unitized with their openings opposed to each other. The inverter cover 23 is arranged in the bottom of the front housing member 21, which is the opposite side from the rear housing member 22. The inverter cover 23 is fixed to the front housing member 21 with being butted to the bottom of the front housing member 21.

The inverter 14 is housed in the inverter cover 23. The inverter 14 drives the electric motor 13. The rotary shaft 12 is supported by the housing 11 in a rotatable state. A ring-shaped first bearing holding part 31 protruding from the bottom is provided in the bottom of the front housing member 21. A first radial bearing 32, which rotationally supports a first end of the rotary shaft 12, is provided inside in the radial direction of the first bearing holding part 31. A ring-shaped second bearing holding part 33 protruding from the bottom is provided in the bottom of the rear housing member 22. A second radial bearing 34 is also provided inside the radial direction of the second bearing holding part 33. The second radial bearing 34 rotationally supports the second end of the rotary shaft 12, which is on the opposite side from the first end. The axial direction Z of the rotary shaft 12 matches the axial direction of the housing 11.

As shown in FIGS. 1 to 4, the front cylinder 40 houses the front rotor 60. The front cylinder 40 has a tubular shape with a closed end formed to be somewhat smaller than the rear housing member 22. The front cylinder 40 is opened toward the bottom of the rear housing member 22. The front cylinder 40 includes a front cylinder bottom 41, and a front cylinder side wall portion 42 extending from the front cylinder bottom 41 toward the rear housing member 22. The front cylinder side wall portion 42 is a first cylindrical portion, and enters inside the rear housing member 22.

As shown in FIGS. 3 and 4, the front cylinder 40 includes a front cylinder inner circumferential surface 43 as a first inner circumferential surface. The front cylinder inner circumferential surface 43 is a cylindrical surface extending in an axial direction Z. The front cylinder 40 further includes a front large diameter surface 44 whose diameter is larger than the front cylinder inner circumferential surface 43. The front large diameter surface 44 is provided in a tip part (open end) of the front cylinder side wall portion 42. A front stepped surface 45 is formed between the front cylinder inner circumferential surface 43 and the front large diameter surface 44.

A bulged part 46 projecting to the radially outside of the rotary shaft 12 is provided in the front cylinder side wall portion 42. The bulged part 46 is provided in the base end of the front cylinder side wall portion 42, that is, near the front cylinder bottom 41. The front housing member 21 and the rear housing member 22 are formed with the bulged part 46 being inserted therebetween. The housings 21 and 22 regulate the position gap in the axial direction Z of the front cylinder 40.

As shown in FIG. 4, the front cylinder bottom 41 has a stepped shape in the axial direction Z. The front cylinder bottom 41 includes a first bottom 41a arranged on the central side, and a second bottom 41b arranged radially outside of the first bottom 41a, and closer to the rear housing member 22 than the first bottom 41a. A front insertion hole 41c, to which the rotary shaft 12 can be inserted, is formed in the first bottom 41a. The rotary shaft 12 is inserted into the front insertion hole 41c.

As shown in FIG. 1, the front housing member 21 and the front cylinder bottom 41 form a motor chamber A1, and house the electric motor 13 in the motor chamber A1. The electric motor 13 rotates the rotary shaft 12 in the direction indicated by an arrow M when driving power is supplied from the inverter 14. The inlet 11a is provided in the front housing member 21 that forms the motor chamber A1. Therefore, the suction fluid drawn in from the inlet 11a is introduced into the motor chamber A1. That is, the suction fluid exists in the motor chamber A1.

Within the compressor 10, the inverter 14, the electric motor 13, and the rotors 60 and 80 are arranged in order in the axial direction Z. The position of each of these parts is arbitrary, and the inverter 14 may be arranged radially outside of the electric motor 13.

As shown in FIGS. 2 to 4, the rear cylinder 50 has a tubular shape with a closed end. The rear cylinder 50 is opened toward the bottom of the rear housing member 22. The rear cylinder 50 is formed to be somewhat smaller than the front cylinder 40, and is housed in the rear housing member 22. The rear cylinder 50 is fitted to the front cylinder 40 with the open end of the rear cylinder 50 being butted to the bottom of the rear housing member 22.

The rear cylinder 50 includes an intermediate wall portion 51 forming the bottom of the rear cylinder 50, and a rear cylinder side wall portion 55 extending in the axial direction Z toward the rear housing member 22 from the intermediate wall portion 51. The rear cylinder side wall portion 55 and the intermediate wall portion 51 correspond to a second cylindrical portion and a wall portion, respectively.

As shown in FIG. 4, the intermediate wall portion 51 is arranged so that its wall thickness direction matches the axial direction Z. Therefore, the intermediate wall portion 51 includes a first wall surface 52 and a second wall surface 53 that are perpendicular to the axial direction Z. The intermediate wall portion 51 has a ring shape, and is fitted to the front cylinder 40. A wall through-hole 54 extending through the axial direction Z is formed in the intermediate wall portion 51. The wall through-hole 54 is a through-hole having a larger diameter than the rotary shaft 12. The rotary shaft 12 is inserted into the wall through-hole 54.

The rear cylinder side wall portion 55 has a cylindrical shape extending in the axial direction Z, and includes a rear cylinder inner circumferential surface 56 as a second inner circumferential surface, and a rear cylinder outer circumferential surface 57. The rear cylinder inner circumferential surface 56 is a cylindrical surface having a smaller diameter than the front cylinder inner circumferential surface 43. Therefore, the rear cylinder inner circumferential surface 56 is arranged inside in the radial direction of the front cylinder inner circumferential surface 43. The rear cylinder outer circumferential surface 57 includes several cylindrical surfaces having different diameters, and thus has a stepped shape. The rear cylinder outer circumferential surface 57 includes a first part surface 57a, a second part surface 57b whose diameter is larger than the first part surface 57a, and a third part surface 57c whose diameter is larger than the second part surface 57b.

The first part surface 57a contacts the front cylinder inner circumferential surface 43. The second part surface 57b contacts the front large diameter surface 44. The third part surface 57c is flush with the outer circumferential surface of the front cylinder side wall portion 42. A first rear stepped surface 58 formed between the part surfaces 57a and 57b contacts a front stepped surface 45, and a second rear stepped surface 59 formed between the part surfaces 57b and 57c contacts the open end of the front cylinder 40.

As shown in FIG. 4, the front cylinder bottom 41, the front cylinder inner circumferential surface 43, and the first wall surface 52 form a front housing chamber A2 that houses the front rotor 60. The front housing chamber A2 has a generally cylindrical shape. The inside bottom surface of the rear housing member 22, the rear cylinder inner circumferential surface 56, and the second wall surface 53 form a rear housing chamber A3 that houses the rear rotor 80. The rear housing chamber A3 has a generally cylindrical shape.

Since the diameter of the rear cylinder inner circumferential surface 56 is smaller than the diameter of the front cylinder inner circumferential surface 43, the rear housing chamber A3 is smaller than the front housing chamber A2, and the volume of the rear housing chamber A3 is smaller than the volume of the front housing chamber A2. The housing chambers A2 and A3 are divided by the intermediate wall portion 51. The rotors 60 and 80 are arranged to be opposed to each other in the axial direction Z, with the intermediate wall portion 51 being arranged therebetween.

The rotary shaft 12 and the rotors 60 and 80 have the same axis. That is, the compressor 10 has the structure for axial center movement, instead of eccentric movement. The circumferential directions of the rotors 60 and 80 match the circumferential direction of the rotary shaft 12, the radial directions of the rotors 60 and 80 match the radial direction R of the rotary shaft 12, and the axial directions of the rotors 60 and 80 match the axial direction Z of the rotary shaft 12. Therefore, the circumferential direction, the radial direction R, and the axial direction Z of the rotary shaft 12 may be properly read as the circumferential direction, the radial direction, and the axial direction of the rotors 60 and 80.

As shown in FIGS. 2 to 4, the front rotor 60 has a ring shape, and includes a front through-hole 61 into which the rotary shaft 12 can be inserted. The front through-hole 61 has the same diameter as the rotary shaft 12. The front rotor 60 is attached to the rotary shaft 12 with the rotary shaft 12 being inserted into the front through-hole 61.

The front rotor 60 rotates with the rotation of the rotary shaft 12. That is, the front rotor 60 integrally rotates with the rotary shaft 12. The configuration for the front rotor 60 to integrally rotate with the rotary shaft 12 is arbitrary, and there are, for example, a configuration in which the front rotor 60 is fixed to the rotary shaft 12, and a configuration in which the front rotor 60 is engaged with the outer circumference of the rotary shaft 12.

A front rotor outer circumferential surface 62, which is an outer circumferential surface of the front rotor 60, is a cylindrical surface having the same axis as the rotary shaft 12. The diameter of the front rotor outer circumferential surface 62 is the same as that of the front cylinder inner circumferential surface 43. There may be a slight gap between the front rotor outer circumferential surface 62 and the front cylinder inner circumferential surface 43.

The front rotor 60 includes a front rotor surface 70 as a first rotor surface opposed to first wall surface 52. The front rotor surface 70 has a ring shape. The front rotor surface 70 includes a first front flat surface 71 and a second front flat surface 72 that are perpendicular to the axial direction Z, and a pair of front curving surfaces 73 connecting the front flat surfaces 71 and 72. The first and second front flat surfaces 71 and 72 correspond to first and second flat surfaces, respectively.

As shown in FIG. 4, the front flat surfaces 71 and 72 are shifted to the axial direction Z. The second front flat surface 72 is arranged closer to the first wall surface 52 than the first front flat surface 71. The second front flat surface 72 contacts the first wall surface 52. Additionally, the front flat surfaces 71 and 72 are separated in the circumferential direction of the front rotor 60, and are shifted 180 degrees. The front flat surfaces 71 and 72 have sectoral shapes. In the following description, the circumferential direction positions of the rotors 60 and 80 are called the angular positions.

Each of the pair of front curving surfaces 73 has a sectoral shape. As shown in FIG. 3, the pair of front curving surfaces 73 are opposed to the direction perpendicular to the axial direction Z and the direction along which the front flat surfaces 71 and 72 are arranged. Both of the front curving surfaces 73 have an identical shape. Each of the pair of front curving surfaces 73 connects the front flat surfaces 71 and 72. One of the pair of front curving surfaces 73 connects one ends in the circumferential directions of the front flat surfaces 71 and 72, and the other connects the other ends of in the circumferential directions of the front flat surfaces 71 and 72.

As shown in FIG. 3, the angular position of the boundary part between the front curving surface 73 and the first front flat surface 71 is a first angular position θ1, and the angular position of the boundary part between the front curving surface 73 and the second front flat surface 72 is a second angular position θ2. In FIG. 3, each of the angular positions θ1 and θ2 are indicated by broken lines. However, actually, the boundary parts are continued smoothly.

The front curving surface 73 is a curving surface displaced in the axial direction Z in accordance with the angular position of the front rotor 60. The front curving surface 73 is curved in the axial direction Z so as to be gradually closer to the first wall surface 52 from the first angular position θ1 to the second angular position θ2. Two front curving surfaces 73 are provided on the opposite sides in the circumferential direction of the second front flat surface 72. The front curving surfaces 73 are each curved so as to be gradually separated from the first wall surface 52 as the front curving surfaces 73 are separated from the second front flat surface 72 in the circumferential direction. The front curving surface 73 is curved in the axial direction Z so as to be gradually closer to or distant from the first wall surface 52 between two arbitrary angular positions that are mutually separated in the circumferential direction, which are not limited to the first angular position θ1 and the second angular position θ2.

As shown in FIGS. 2 to 4, the rear rotor 80 has a ring shape, and includes a rear through-hole 81 into which the rotary shaft 12 can be inserted. The rear through-hole 81 has the same diameter as the rotary shaft 12. The rotary shaft 12 is inserted into the rear through-hole 81, and the rear rotor 80 is engaged with the front rotor 60. The engagement of the front rotor 60 and the rear rotor 80 will be described later. The rear rotor 80 rotates with the rotation of the rotary shaft 12. That is, the rear rotor 80 integrally rotates with the rotary shaft 12. The configuration for the rear rotor 80 to integrally rotate with the rotary shaft 12 is arbitrary, and there are, for example, a configuration in which the rear rotor 80 is fixed to the rotary shaft 12, and a configuration in which the rear rotor 80 is engaged with the outer circumference of the rotary shaft 12.

The rear rotor 80 is formed to be smaller than the front rotor 60. The diameter of the rear rotor 80 is smaller than the diameter of the front rotor 60. A rear rotor outer circumferential surface 82, which is an outer circumferential surface of the rear rotor 80, is a cylindrical surface having a smaller diameter than the front rotor outer circumferential surface 62. The diameter of the rear rotor outer circumferential surface 82 is the same as that of the rear cylinder inner circumferential surface 56. There may be a slight gap between the rear rotor outer circumferential surface 82 and the rear cylinder inner circumferential surface 56.

As shown in FIGS. 2 and 4, the rear rotor 80 includes a rear rotor surface 90 as a second rotor surface opposed to the second wall surface 53. The rear rotor surface 90 has a ring shape. The rear rotor surface 90 includes a first rear flat surface 91 and a second rear flat surface 92 that are perpendicular to the axial direction Z, and a pair of rear curving surfaces 93 that connect the rear flat surfaces 91 and 92. The first and second front flat surfaces 91 and 92 correspond to first and second flat surfaces, respectively.

As shown in FIG. 5, the rear flat surfaces 91 and 92 are shifted in the axial direction Z. The second rear flat surface 92 is arranged closer to the second wall surface 53 than the first rear flat surface 91. The second rear flat surface 92 contacts the second wall surface 53. The rear flat surfaces 91 and 92 are separated in the circumferential direction of the rear rotor 80, and are shifted 180 degrees. The rear flat surfaces 91 and 92 have sectoral shapes.

Each of the pair of rear curving surfaces 93 has a sectoral shape. The pair of rear curving surfaces 93 are opposed to the direction perpendicular to the axial direction Z and the direction along which the rear flat surfaces 91 and 92 are arranged. One of the pair of the rear curving surfaces 93 connects one of the ends in the circumferential direction of the rear flat surfaces 91 and 92, and the other connects the other of the ends in the circumferential direction of the rear flat surfaces 91 and 92.

The rotor surfaces 70 and 90 are arranged to be opposed to each other in the axial direction Z with the intermediate wall portion 51 therebetween. The distance between the rotor surfaces 70 and 90 is constant irrespective of the angular positions and the circumferential direction positions of the rotor surfaces 70 and 90. As shown in FIG. 5, the first front flat surface 71 and the second rear flat surface 92 are opposed to each other in the axial direction Z, and the second front flat surface 72 and the first rear flat surface 91 are opposed to each other in the axial direction Z, respectively. The shift amount in the axial direction Z between the front flat surfaces 71 and 72 is the same as the shift amount between the rear flat surfaces 91 and 92. The shift amount in the axial direction Z between the front flat surfaces 71 and 72, and the shift amount between the rear flat surfaces 91 and 92 are called the shift amount L1.

As shown in FIG. 4, the degree of curvature of the front curving surface 73 is the same as the degree of curvature of the rear curving surface 93. That is, the front curving surface 73 and the rear curving surface 93 are curved in the same direction, so that the separation distance is not changed in accordance with the angular positions. Accordingly, the separation distance between the rotor surfaces 70 and 90 is constant irrespective of the angular positions. The rotor surfaces 70 and 90 have an identical shape except that they have different diameters. Since the shapes of the first rear flat surface 91, the second rear flat surface 92, and the rear curving surface 93 are the same as those of the first front flat surface 71, the second front flat surface 72, and the front curving surface 73, a detailed description is omitted.

As shown in FIGS. 2 to 4, the compressor 10 includes a vane 100, and a vane groove 110 into which the vane 100 is inserted. The vane 100 contacts the rotors 60 and 80, and thus moves in the axial direction Z with the rotation of the rotors 60 and 80. The vane 100 is arranged between the rotors 60 and 80, that is, between the rotor surfaces 70 and 90, with the surface of the vane 100 being perpendicular to the circumferential direction of the rotary shaft 12. The vane 100 has a tabular shape having the thickness in the direction perpendicular to the axial direction Z.

The vane 100 has a first vane end 101 and a second vane end 102 as the opposite ends in the axial direction Z. The first vane end 101 contacts the front rotor surface 70, and the second vane end 102 contacts the rear rotor surface 90.

As shown in FIG. 2, the vane groove 110 is formed in the rear cylinder 50. The vane groove 110 is formed over both of the intermediate wall portion 51 and the rear cylinder side wall portion 55. The vane groove 110 is a slit extending through the rear cylinder 50 in a radial direction R. The opposite ends of the vane groove 110 in the radial direction R are opened. The vane groove 110 extends through the intermediate wall portion 51. The end on the front rotor 60 side of the opposite ends of the vane groove 110 in the axial direction Z is opened. The opposite side surfaces of the vane groove 110 are opposed to corresponding surfaces of the opposite surfaces of the vane 100. The width of the vane groove 110, that is, the distance between the side surfaces of the vane groove 110, is the same as or slightly larger than the thickness of the vane 100.

As shown in FIG. 4, the vane groove 110 extends in the axial direction Z from the intermediate wall portion 51 to the middle of the rear cylinder side wall portion 55. The vane groove 110 also exists radially outside of the rear rotor 80. The length in the axial direction Z of the vane groove 110 is the same as or longer than the length in the axial direction Z of the vane 100. By inserting the vane 100 into the vane groove 110, the movement of the vane 100 in the circumferential direction is restricted. In contrast, it is permitted for the vane 100 to move in the axial direction Z along the vane groove 110.

According to this configuration, when the rotors 60 and 80 rotate, the vane 100 moves in the axial direction Z while sliding on the rotor surfaces 70 and 90. Accordingly, the first vane end 101 of the vane 100 enters into the front housing chamber A2, or the second vane end 102 enters into the rear housing chamber A3. In contrast, the vane 100 contacts both side surfaces of the vane groove 110, and thus the movement in the circumferential direction is restricted. Therefore, even if the rotors 60 and 80 are rotated, the vane 100 is not rotated.

The vane groove 110 allows the arrangement of the vane 100 over the housing chambers A2 and A3 and restricts the rotation of the vane 100, even if the rotors 60 and 80 are rotated. The movement distance of the vane 100 is the displacement amount (the shift amount L1) in the axial direction Z between the front flat surfaces 71 and 72 (or between the rear flat surfaces 91 and 92). During the rotation of the rotors 60 and 80, the vane 100 continues to contact the rotor surfaces 70 and 90. That is, the vane 100 does not intermittently contact the rotor surfaces 70 and 90, and does not periodically repeat separation from and contact with the rotor surfaces 70 and 90.

As shown in FIG. 4, a front compression chamber A4 is formed in the front housing chamber A2 by the front rotor 60 (the front rotor surface 70), the front cylinder inner circumferential surface 43, and the first wall surface 52.

A rear compression chamber A5 is formed in the rear housing chamber A3 by the rear rotor 80 (the rear rotor surface 90), the rear cylinder inner circumferential surface 56, and the second wall surface 53. In the compression chambers A4 and A5, with the rotation of the rotary shaft 12, their volumes are periodically changed, and suction/compression of fluid are performed by the vane 100. That is, the vane 100 produces a volume change in the compression chambers A4 and A5. This point will be described later.

Since the front rotor 60 is formed to be larger than the rear rotor 80, the front compression chamber A4 is larger than the rear compression chamber A5. That is, the maximum volume of the front compression chamber A4 is larger than the maximum volume of the rear compression chamber A5.

As shown in FIGS. 2 and 3, an introduction port 111 for introducing the suction fluid in the motor chamber A1 into the front compression chamber A4 is formed in the front rotor 60. The introduction port 111 has an oval shape that is long in the radial direction R. The shape of the introduction port 111 is not limited to this, and is arbitrary.

The introduction port 111 extends through the front rotor 60 in the axial direction Z. The introduction port 111 is arranged near the radially outer end of the front rotor 60. The introduction port 111 is arranged at a position where the introduction port 111 communicates with the front compression chamber A4 at the phase at which the volume of the front compression chamber A4 becomes large, and does not communicate with the front compression chamber A4 at the phase at which the volume of the front compression chamber A4 becomes small.

The introduction port 111 is provided near the boundary between the second front flat surface 72 and the front curving surface 73, specifically, near the end in the circumferential direction of the front curving surface 73 close to the second front flat surface 72. Further, the introduction port 111 is formed in the front curving surface 73 on the trailing side in the rotation direction with respect to the second front flat surface 72.

As shown in FIGS. 2 and 3, communication holes 112 communicating with the introduction port 111 are formed in the front cylinder 40. The communication holes 112 are provided at the positions corresponding to the introduction port 111. When seen from the axial direction Z, the communication holes 112 are formed at the positions that overlap with the trajectory of the introduction port 111 when the front rotor 60 is rotated. The communication holes 112 extend in the circumferential direction of the rotary shaft 12, and four communication holes 112 are separated from each other in the circumferential direction. Accordingly, even if the position of the introduction port 111 changes with the rotation of the front rotor 60, the communication between the introduction port 111 and the communication holes 112 is easily maintained.

A discharge port 113 that discharges the compression fluid compressed in the rear compression chamber A5 is formed in the rear rotor 80. The discharge port 113 extends through the rear rotor 80 in the axial direction Z. The discharge port 113 is formed to be smaller than the introduction port 111. The discharge port 113 is circular. The shape of the discharge port 113 is not limited to this, and is arbitrary.

The discharge port 113 is arranged at a position where the discharge port 113 communicates with the rear compression chamber A5 at the phase at which the volume of the rear compression chamber A5 becomes small, and does not communicate with the rear compression chamber A5 at the phase at which the volume of the rear compression chamber A5 becomes large. The discharge port 113 is provided near the boundary between the second rear flat surface 92 and the rear curving surface 93, specifically, at the end in the circumferential direction of the rear curving surface 93 close to the second rear flat surface 92. Further, the discharge port 113 is formed in the rear curving surface 93 that is on the leading side in the rotation direction with respect to the second rear flat surface 92.

When seen from the axial direction Z, the introduction port 111 is arranged on the same side as the discharge port 113, instead of the opposite side from the discharge port 113, on the basis of the center line passing through the centers of the rotors 60 and 80, and extending in the direction along which the flat surfaces 71 and 72 are arranged. However, the positions of the introduction port 111 and the discharge port 113 are arbitrary. A discharge valve that closes the discharge port 113 and makes the discharge port 113 open based on application of a specified pressure may be provided. The discharge valve is not essential.

As shown in FIG. 1, the compressor 10 includes a discharge chamber A6 into which the compression fluid discharged from the discharge port 113 flows, and a discharge passage 114 that connects the discharge chamber A6 and the outlet 11b. The discharge chamber A6 is formed by the rear cylinder 50 and the rear housing member 22. The discharge chamber A6 is arranged between the discharge port 113 and the rear housing member 22. When seen from the axial direction Z, the discharge chamber A6 is formed in a ring shape so as to overlap with the trajectory of the discharge port 113 accompanying the rotation of the rear rotor 80. Accordingly, it is possible to limit the situation in which the discharge port 113 and the discharge chamber A6 do not communicate with each other, depending on the angular position of the rear rotor 80. According to this configuration, the fluid discharged from the discharge port 113 is discharged from the outlet 11b via the discharge chamber A6 and the discharge passage 114.

The compressor 10 includes a communication mechanism 120 that switches between a communicating state in which the compression chambers A4 and A5 communicate with each other, and a non-communicating state in which the compression chambers A4 and A5 are not communicating with each other. A detailed configuration of the communication mechanism 120 is described below.

As shown in FIGS. 2 to 4, the communication mechanism 120 includes a front boss portion 121 as a first boss portion provided in the front rotor 60, a front rotary valve 122 as a first engagement portion, a rear boss portion 123 as a second boss portion provided in the rear rotor 80, and a rear rotary valve 124 as a second engagement portion.

The front boss portion 121 protrudes toward the rear rotor 80 from the front rotor surface 70. The front boss portion 121 protrudes further toward the rear rotor surface 90 than the second front flat surface 72. The front boss portion 121 includes a cylinder provided in the radially inner end of the front rotor surface 70. The rotary shaft 12 is inserted into the front boss portion 121. The outer diameter of the front boss portion 121 is substantially the same as the diameter of the wall through-hole 54. The front boss portion 121 is fitted to be slidable from the first wall surface 52 to the wall through-hole 54.

As shown in FIG. 3, the front rotary valve 122 protrudes toward the rear rotor 80 from the tip surface of the front boss 121. Two front rotary valves 122 are provided at the positions separated in the circumferential direction.

The front rotary valves 122 have sectoral shapes. The inner circumferential surfaces of the front rotary valves 122 are flush with the inner circumferential surface of the front boss portion 121, and contact the outer circumferential surface of the rotary shaft 12. The outer circumferential surfaces of the front rotary valves 122 are flush with the outer circumferential surface of the front boss portion 121.

As shown in FIGS. 2 and 4, the rear boss portion 123 protrudes toward the front rotor 60 from the rear rotor surface 90. The rear boss portion 123 protrudes further toward the front rotor surface 70 than the second rear flat surface 92. The rear boss portion 123 includes a cylinder provided in the radially inner end of the rear rotor surface 90. The rotary shaft 12 is inserted into the rear boss portion 123. The outer diameter of the rear boss portion 123 is substantially the same as the diameter of the wall through-hole 54. The rear boss portion 123 is fitted to be slidable from the second wall surface 53 to the wall through-hole 54.

The rear rotary valve 124 protrudes toward the front rotor 60 from the tip surface of the rear boss 123. The rear rotary valve 124 consists of a columnar body including a curved inner circumferential surface and an outer circumferential surface. The inner circumferential surface of the rear rotary valve 124 is flush with the inner circumferential surface of the rear boss portion 123, and contacts the outer circumferential surface of the rotary shaft 12. The outer circumferential surface of the rear rotary valve 124 is flush with the outer circumferential surface of the front rotary valves 122. The length of the circumferential direction of rear rotary valve 124 is the same as the interval distance of the circumferential direction of the front rotary valves 122.

As shown in FIGS. 5 and 6, the rear rotary valve 124 is engaged with the two front rotary valves 122 in the circumferential direction. The rear rotary valve 124 is fitted between the rotary valves 122 by being sandwiched by the two front rotary valves 122 from the circumferential direction. The relative positions in the circumferential direction of the rotors 60 and 80 are specified by fitting the rotary valves 122 and 124.

One sectoral connecting valve 125 is formed by the front rotary valves 122 and the rear rotary valve 124. The connecting valve 125 is arranged in the wall through-hole 54. The rotary valves 122 and 124 are engaged with each other within the wall through-hole 54.

The connecting valve 125 does not have a closed ring shape, and has a sectoral shape. Therefore, an open space 126 where fluid can move is formed in the wall through-hole 54. The open space 126 is formed between the rotary shaft 12 and a wall inner circumferential surface 54a, which is the inner circumferential surfaces of the wall through-hole 54. The open space 126 is formed by the end faces in the circumferential direction of the connecting valve 125, the outer circumferential surface of the rotary shaft 12, and the wall inner circumferential surface 54a.

The connecting valve 125 includes a valve outer circumferential surface 125a having the same diameter as the diameter of the wall through-hole 54. The valve outer circumferential surface 125a is configured by the outer circumferential surfaces of the rotary valves 122 and 124. Since the outer circumferential surfaces of the rotary valves 122 and 124 are flush with each other, the valve outer circumferential surface 125a forms one continuous circumferential surface. The valve outer circumferential surface 125a contacts the wall inner circumferential surface 54a of the wall through-hole 54. The wall inner circumferential surface 54a is also an inner circumferential surface of the intermediate wall portion 51 formed in ring shape.

The communication mechanism 120 includes a communication passage 130 that communicates between the compression chambers A4 and A5. The communication passage 130 includes a front-side opening 131, a rear side opening 132, and a communication groove 133.

As shown in FIG. 5, the front-side opening 131 and the rear side opening 132 are formed in the intermediate wall portion 51. The openings 131 and 132 are separated in the circumferential directions of the rotors 60 and 80. The front-side opening 131 and the rear side opening 132 are arranged at either side of the vane 100. The front-side opening 131 is formed on one surface of the vane 100 located on the trailing side in the rotation direction of the rotors 60 and 80, and the rear side opening 132 is formed on the other surface of the vane 100 located on the leading side in the rotation direction of the rotors 60 and 80, respectively. The openings 131 and 132 communicate with the vane groove 110.

As shown in FIG. 3, the front-side opening 131 is opened toward the front compression chamber A4 and the wall through-hole 54. The front-side opening 131 is formed in the both of the first wall surface 52 and the wall inner circumferential surface 54a in the intermediate wall portion 51. The front-side opening 131 is configured so that the fluid in the front compression chamber A4 can be made to flow into the wall through-hole 54.

The front-side opening 131 is not formed in the second wall surface 53. That is, the front-side opening 131 does not extend through the intermediate wall portion 51 in the axial direction Z, and does not directly communicate with the front compression chamber A4 and the rear compression chamber A5 to each other.

As shown in FIG. 2, the rear side opening 132 is opened toward the rear compression chamber A5 and the wall through-hole 54. The rear side opening 132 is formed in both of the second wall surface 53 and the wall inner circumferential surface 54a in the intermediate wall portion 51. The rear side opening 132 is configured so that the fluid in the rear compression chamber A5 can be made to flow into the wall through-hole 54. In contrast, the rear side opening 132 is not formed in the first wall surface 52. That is, the rear side opening 132 does not extend through the intermediate wall portion 51 in the axial direction Z, and does not directly communicate with the front compression chamber A4 and the rear compression chamber A5 to each other.

As shown in FIG. 5, the front-side opening 131 has a half-U shape, and extends in the radial direction R. The rear side opening 132 has a half-U shape that is symmetrical to the front-side opening 131. The shapes of the openings 131 and 132 are not limited to these, and are arbitrary. The vane 100 divides the front-side opening 131 and the rear side opening 132. The vane 100 restricts the fluid from directly flowing into the rear side opening 132 from the front-side opening 131.

The communication groove 133 is a part that is recessed outward in the radial direction of the wall inner circumferential surface 54a. The communication groove 133 is arranged between the front-side opening 131 and the rear side opening 132 in the wall inner circumferential surface 54a so as to bypass the vane 100. The communication groove 133 extends in the circumferential direction of the wall inner circumferential surface 54a. The communication groove 133 communicates with the rear side opening 132, and communicates with the open space 126. The circumferential direction of the wall inner circumferential surface 54a matches the circumferential directions of the rotors 60 and 80. Therefore, the circumferential direction of the wall inner circumferential surface 54a can also be said to be the circumferential directions of the rotors 60 and 80.

In contrast, the communication groove 133 does not directly communicate with the front-side opening 131. The communication groove 133 and the front-side opening 131 are separated in the circumferential direction of the wall inner circumferential surface 54a. Therefore, the fluid does not directly flow into the communication groove 133 from the front-side opening 131. The communication groove 133 is not formed, and a groove-less surface 54aa exists between the communication groove 133 and the front-side opening 131 in the wall inner circumferential surface 54a.

FIG. 5 shows a case where the connecting valve 125 is arranged radially inside of the front-side opening 131. In this case, the connecting valve 125 closes the opening part that is radially inside of the front-side opening 131. Accordingly, the inflow of the fluid that goes to the communication groove 133 from the front-side opening 131 is restricted. Accordingly, the compression chambers A4 and A5 are in the non-communicating state in which they are not communicating with each other. Especially, when the connecting valve 125 is arranged radially inside with respect to the groove-less surface 54aa, the valve outer circumferential surface 125a of the connecting valve 125 contacts the groove-less surface 54aa. Accordingly, the leakage of the fluid that goes to the communication groove 133 from the front-side opening 131 is regulated.

FIG. 6 shows a case where the connecting valve 125 is moved in the circumferential direction of the rotors 60 and 80 with respect to the front-side opening 131. In this case, the connecting valve 125 does not close the opening part that is radially inside of the front-side opening 131. Accordingly, the inflow of the fluid that goes to the communication groove 133 from the front-side opening 131 via the open space 126 is permitted. Accordingly, the fluid in the front compression chamber A4 passes through the front-side opening 131→the open space 126→the communication groove 133→the rear side opening 132, and moves to the rear compression chamber A5. Accordingly, the compression chambers A4 and A5 are in the communicating state, in which they are communicating with each other.

The connecting valve 125 moves between the closed position for closing the front-side opening 131, and the open position for opening the front-side opening 131 in accordance with the angular positions of the rotors 60 and 80. When the connecting valve 125 is moved to the open position, the front-side opening 131 and the communication groove 133 communicate with each other via the open space 126.

In this configuration, the communication period of the front compression chamber A4 and the rear compression chamber A5 in one cycle of rotation of the rotors 60 and 80 is defined by the length in the circumferential direction of the valve outer circumferential surface 125a (the angle range occupied by the connecting valve 125). Additionally, the timing at which the compression chambers A4 and A5 communicate with each other in one cycle of rotation of the rotors 60 and 80 is defined by the angular position of the connecting valve 125. Accordingly, when the angular position of the connecting valve 125, or the length in the circumferential direction of the valve outer circumferential surface 125a is adjusted, the timing at which the compression chambers A4 and A5 communicate with each other and the communication period are adjusted.

As shown in FIGS. 4 and 5, the inner end face 103, which is a radially inside end face of the vane 100, contacts the outer circumferential surfaces of the boss portions 121 and 123, and the valve outer circumferential surface 125a. The outer circumferential surfaces of the boss portions 121 and 123 are flush with each other, the outer circumferential surfaces of the boss portions 121 and 123 are flush with the valve outer circumferential surface 125a, and the outer circumferential surfaces of the rotary valves 122 and 124 are flush with each other. The inner end face 103 of the vane 100 is a concave surface that is curved with the same curvature as the outer circumferential surfaces of the boss portions 121 and 123, and the valve outer circumferential surface 125a. Therefore, the inner end face 103 of the vane 100 comes into surface contact with the outer circumferential surfaces of the boss portions 121 and 123, and the valve outer circumferential surface 125a.

An outer end face 104, which is a radially outside end face of the vane 100, is flush with the first part surface 57a of the rear cylinder 50. The outer end face 104 of the vane 100 contacts the front cylinder inner circumferential surface 43 of the front cylinder 40. The vane 100 is sandwiched by the outer circumferential surfaces of the boss portions 121 and 123 and the valve outer circumferential surface 125a, and the front cylinder inner circumferential surface 43 from the radial direction R. Accordingly, it is possible to limit the position shift in the radial direction R of the vane 100. Additionally, it is possible to limit the fluid from leaking from the boundary part between the vane 100 (the inner end face 103) and the outer circumferential surfaces of the boss portions 121 and 123 and the valve outer circumferential surface 125a, or from the boundary part between the vane 100 (the outer end face 104) and the front cylinder inner circumferential surface 43.

Using FIGS. 7 to 13 in addition to FIGS. 2 to 4, a detailed description is given of the vane ends 101 and 102 and the curving surfaces 73 and 93. FIGS. 8, 12, and 13 schematically show the curvature change and the degree of curvature of a contact line.

FIG. 8 is a graph showing the displacement in the axial direction Z in accordance with the angular position on the rotor surface 70. The continuous line in FIG. 8 shows the displacement in the axial direction Z of the radially inner end of the front rotor surface 70. The long dashed short dashed line in FIG. 8 shows the displacement in the axial direction Z of the radially outer end of the front rotor surface 70. The vertical axis of the graph in FIG. 8 shows the displacement amount in the axial direction Z on the basis of the first front flat surface 71. In FIG. 8, it is shown that the more distant from 0 the displacement in the axial direction Z becomes, the closer to the first wall surface 52 the front rotor surface 70 becomes.

FIG. 8 can also be said to be the graph showing the displacement in the axial direction Z of the rear rotor surface 90. In this case, the continuous line in FIG. 8 shows the displacement in the axial direction Z of the radially inner end of the rear rotor surface 90. The long dashed short dashed line in FIG. 8 shows the displacement in the axial direction Z of the radially outer end of the rear rotor surface 90. The vertical axis of the graph in FIG. 8 shows the displacement amount in the axial direction Z on the basis of the first rear flat surface 91. In FIG. 8, it is shown that the more distant from 0 the displacement in the axial direction Z becomes, the closer to the second wall surface 53 the rear rotor surface 90 becomes.

As shown in FIG. 7, the vane ends 101 and 102 have curved shapes that are convex in the direction in which the vane ends 101 and 102 are separated from each other. The first vane end 101 is curved so as to be convex toward the front rotor surface 70, and the second vane end 102 is curved so as to be convex toward the rear rotor surface 90. The vane ends 101 and 102 extend in the vertical direction perpendicular to the axial direction Z, and are not inclined in the axial direction Z.

The vane ends 101 and 102 contact the curving surfaces 73 and 93, which are curved in the axial direction Z, in a linear manner. The contacting part between the vane ends 101 and 102 and the curving surfaces 73 and 93 are shifted in accordance with the degrees of curvature in the axial direction Z of the curving surfaces 73 and 93, more particularly, in accordance with the curvatures of the curving surfaces 73 and 93.

Next, the curving surfaces 73 and 93 are described. Hereinafter, though a description is given of the front rotor surface 70, the same applies to the rear rotor surface 90.

The front flat surfaces 71 and 72 are flat surfaces that are perpendicular to the axial direction Z. Therefore, the radially inner ends and the radially outer ends of the front flat surfaces 71 and 72 are not displaced irrespective of the angular positions. In FIG. 8, the vicinity of 0 degrees corresponds to the second front flat surface 72, and the vicinity of 180 degrees corresponds to the first front flat surface 71.

As shown in FIGS. 4 and 8, the front curving surface 73 includes a front concave surface 74 that is curved in the axial direction Z so as to be concave toward the first wall surface 52, and a front convex surface 75 that is curved in the axial direction Z so as to be convex toward the first wall surface 52.

The front concave surface 74 is arranged closer to the first front flat surface 71 than the second front flat surface 72, and continues from the first front flat surface 71. The front convex surface 75 is arranged closer to the second front flat surface 72 than the first front flat surface 71, and continues from the second front flat surface 72. The front concave surface 74 is connected to the front convex surface 75. The front curving surface 73 has an inflection point (inflection angle position) θm.

The angular range occupied by the front concave surface 74 is the same as the angular range occupied by the front convex surface 75, and the angular positions at 90 degrees and 270 degrees are equivalent to the inflection point θm, respectively. The angular ranges may be different from each other, and the inflection point θm is not limited to the above-described angular position, and is arbitrary.

As shown in FIG. 9, the front concave surface 74 includes a front concave surface radially inner end 74a and a front concave surface radially outer end 74b as the opposite ends in the radial direction R. Similarly, the front convex surface 75 includes a front convex surface radially inner end 75a and a front convex surface radially outer end 75b as the opposite ends in the radial direction R. The radially inner ends 74a and 75a and the radially outer ends 74b and 75b are both circular.

The radially inner ends 74a and 75a form the radially inner end of the front curving surface 73. The diameters of the radially inner ends 74a and 75a are the same as the outer diameter of the front boss portion 121. The radially inner ends 74a and 75a are connected to each other. The front concave surface radially inner end 74a is connected to the radially inner end of the first front flat surface 71, and the front convex surface radially inner end 75a is connected to the radially inner end of the second front flat surface 72. As indicated by the continuous line in FIG. 8, the displacement waveform in the axial direction Z of the radially inner end of the front rotor surface 70 becomes a smooth curved line.

The radially outer ends 74b and 75b form the radially outer end of the front curving surface 73. The radially outer ends 74b and 75b are connected to each other. The front concave surface radially outer end 74b is connected to the radially outer end of the first front flat surface 71, and the front convex surface radially outer end 75b is connected to the radially outer end of the second front flat surface 72. As indicated by the long dashed short dashed line in FIG. 8, the displacement waveform in the axial direction Z of the radially outer end of the front rotor surface 70 becomes a smooth curved line.

The curvature indicating the displacement condition in the axial direction Z in accordance with the angular position is changed between the radially inner ends 74a and 75a and the radially outer end 74b and 75b. In the following description, the curvature means the curvature with respect to the axial direction Z, and the radius of curvature means the radius of curvature of the curvature with respect to the axial direction Z. That is, the curvature and the radius of curvature are parameters representing the displacement with respect to the axial direction Z, and do not represent the curvature and the radius of curvature of the arcs of the radially inner ends 74a and 75a and the radially outer ends 74b and 75b seen from the axial direction Z, for example.

Particularly, the radius of curvature of the front concave surface radially inner end 74a is smaller than the radius of curvature of the front concave surface radially outer end 74b. As shown in FIG. 8, the curvature of the displacement curve in the axial direction Z of the front concave surface radially inner end 74a with respect to the angular change (phase) is smaller than the curvature of the displacement curve in the axial direction Z of the front concave surface radially outer end 74b with respect to the angular change. Accordingly, in the front concave surface 74, the difference in the axial direction Z between the front concave surface radially outer end 74b and the front concave surface radially inner end 74a becomes gradually larger from the first front flat surface 71 toward the inflection point θm.

Additionally, the radius of curvature of the front convex surface radially inner end 75a is smaller than the radius of curvature of the front convex surface radially outer end 75b. As shown in FIG. 8, the curvature of the displacement curve in the axial direction Z of the front convex surface radially inner end 75a with respect to the angular change (phase) is larger than the curvature of the displacement curve in the axial direction Z of the front convex surface radially outer end 75b with respect to the angular change. Accordingly, in the front convex surface 75, the difference between the front convex surface radially outer end 75b and the front convex surface radially inner end 75a becomes gradually smaller from the inflection point θm toward the second front flat surface 72.

That is, the front curving surface 73 is formed to be gradually inclined such that the radially inner end is more separated from the first wall surface 52 than the radially outer end from the first front flat surface 71 toward the inflection point θm, and such that the radially inner end and the radially outer end approach the same position in the axial direction Z from the inflection point θm toward the second front flat surface 72. That is, at the inflection point θm, which is the boundary part between the front concave surface 74 and the front convex surface 75, the difference in the axial direction Z between the radially outer end and the radially inner end in the front curving surface 73 is maximized. In contrast, in the opposite ends in the circumferential direction in the front curving surface 73, there is no difference between the radially outer end and the radially inner end, and the both are arranged at the same position in the axial direction Z.

Similarly, as shown in FIGS. 4 and 8, the rear curving surface 93 includes a rear concave surface 94 that is curved in the axial direction Z so as to be concave toward the second wall surface 53, and a rear convex surface 95 that is curved in the axial direction Z so as to be convex toward the second wall surface 53. The rear curving surface 93 has the inflection point θm at the same angular position as the front curving surface 73. The rear concave surface 94 is connected to the rear convex surface 95. The front concave surface 74 and the rear convex surface 95 are opposed to each other in the axial direction Z, and the front convex surface 75 and the rear concave surface 94 are opposed to each other in the axial direction Z.

As shown in FIG. 10, the rear concave surface 94 includes a rear concave surface radially inner end 94a and a rear concave surface radially outer end 94b. The rear convex surface 95 includes a rear convex surface radially inner end 95a connected to the rear concave surface radially inner end 94a, and a rear convex surface radially outer end 95b connected to the rear concave surface radially outer end 94b.

The degrees of curvature of the rear concave surface 94 and the rear convex surface 95 are the same as the degrees of curvature of the front concave surface 74 and the front convex surface 75. The radius of curvature of the rear concave surface radially inner end 94a is smaller than the radius of curvature of the rear concave surface radially outer end 94b, and the radius of curvature of the rear convex surface radially inner end 95a is smaller than the radius of curvature of the rear convex surface radially outer end 95b.

The front concave surface 74 is formed such that the radius of curvature becomes gradually smaller from the front concave surface radially outer end 74b toward the front concave surface radially inner end 74a. The front convex surface 75 is formed such that the radius of curvature becomes gradually smaller from the front convex surface radially outer end 75b toward the front convex surface radially inner end 75a. Accordingly, the curvature change in the radial direction R in the front concave surface 74 and the front convex surface 75 is continuous.

As shown in FIG. 11, the front curving surface 73 and the rear curving surface 93 are mutually inclined in the axial direction Z such that the radially inner ends are more separated from the second wall surface 53 than the radially outer ends at least at the inflection point θm (the boundary part between the concave surfaces 74 and 94 and the convex surfaces 75 and 95). Then, when the vane 100 is arranged at the angular position corresponding to the inflection point θm, the first vane end 101 contacts both of the radially inner end and radially outer end of the front curving surface 73, and the second vane end 102 contacts both of the radially inner end and radially outer end of the rear curving surface 93.

In other words, the front curving surface 73 and the rear curving surface 93 are gradually concaved from the radially outer end toward the radially inner end at least at the inflection point θm, and the concave from the radially outer end toward the radially inner end becomes gentle from the inflection point θm toward the angular positions θ1 and θ2.

A detailed description is given of the contacting manner between the curving surfaces 73 and 93 configured as described above and the vane end 101 and 102.

As shown in FIG. 12, the front curving surface 73 is in line contact with the first vane end 101. The contact line (line of contact) between the front curving surface 73 and the first vane end 101 is called a front contact line (front line of contact) P1.

As described above, the first vane end 101 extends in the vertical direction perpendicular to the axial direction Z, and the position of the axial direction Z is not displaced. In contrast, in the front curving surface 73, the radius of curvature is different between the radially inner end and the radially outer end, and the radially inner end and the radially outer end are displaced in the axial direction Z at least at the inflection point θm. Therefore, the angular position at which the front curving surface 73 contacts the first vane end 101 differs between the radially inner end and radially outer end of the front curving surface 73. Accordingly, the front contact line P1 becomes a curved line instead of a straight line extending in the radial direction R.

Similarly, as shown in FIG. 13, the rear curving surface 93 is in line contact with the second vane end 102. The contact line (line of contact) between the rear curving surface 93 and the second vane end 102 is called a rear contact line (rear line of contact) P2.

As described above, the second vane end 102 extends in the vertical direction perpendicular to the axial direction Z, and the position of the axial direction Z is not displaced. In contrast, in the rear curving surface 93, the radius of curvature is different between the radially inner end and the radially outer end, and the radially inner end and the radially outer end are displaced in the axial direction Z at least at the inflection point θm. Therefore, similar to the front contact line P1, the rear contact line P2 becomes a curved line instead of a straight line extending in the radial direction R.

A vane thickness D, which is the thickness of the vane 100, is set such that the vane ends 101 and 102 contact the curving surfaces 73 and 93 from the radially inner ends to the radially outer ends, irrespective of the angular positions of the curving surfaces 73 and 93. Particularly, the vane thickness D is set such that the vane ends 101 and 102 contact the radially inner ends of the curving surfaces 73 and 93, when the vane 100 is arranged at the angular position corresponding to the inflection point θm. It can be said that the vane thickness D is the length of the vane 100 in the direction perpendicular to both of the axial direction Z and the longitudinal direction of the vane ends 101 and 102. Therefore, the thickness direction of the vane 100 is the direction that is perpendicular to both of the axial direction Z and the longitudinal direction of the vane ends 101 and 102.

The radii of curvature of the vane ends 101 and 102, which are curved so as to be convex toward the rotor surfaces 70 and 90, is arbitrary, as long as the vane ends 101 and 102 can contact the curving surfaces 73 and 93 from the radially inner ends to the radially outer ends, irrespective of the angular positions of the rotors 60 and 80. For example, the larger the radii of curvature of the vane ends 101 and 102 are, the larger the difference in the circumferential direction of the contact position between the radially inner end and the radially outer end of the curving surfaces 73 and 93 becomes. In consideration of this point, the radii of curvature of the vane ends 101 and 102 may be made larger than the radius of curvature in the case where the vane ends 101 and 102 have semicircle shapes. Accordingly, the contact lines P1 and P2 can be more curved.

When the front curving surface 73 is curved in the axial direction Z so as to be close to the first wall surface 52 from a first angular position θ1 toward a second angular position θ2, the rear curving surface 93, which is opposed to the front curving surface 73, is curved in the axial direction Z so as to be distant from the second wall surface 53 such that the separation distance from the front curving surface 73 becomes constant. That is, when one of the curving surfaces 73 and 93 is upwardly inclined, the other is downwardly inclined. Accordingly, when seen in the axial direction Z, the front contact line P1 is curved in the direction opposite to the rear contact line P2.

The separation distance between the curving surfaces 73 and 93 being constant may mean that the separation distance is constant at angular positions of the same radius. When the curving surfaces 73 and 93 have an identical shape except for different diameters, the separation distance at arbitrary radius positions of the curving surfaces 73 and 93 becomes constant, without being changed in accordance with the angular positions. Additionally, the separation distance being constant means that some errors are included if the rotors 60 and 80 can be rotated within a range in which the vane ends 101 and 102 are contacting the curving surfaces 73 and 93.

Next, using FIGS. 14 and 15, a detailed description is given of the positional relationship among the introduction port 111, the discharge port 113, and the openings 131 and 132, and the compression chambers A4 and A5.

FIG. 14B is a cross-sectional view showing the rotors 60 and 80 and the vane 100 in the state shown in FIG. 14A, and FIG. 15B is a cross-sectional view showing the rotors 60 and 80 and the vane 100 in the state shown in FIG. 15A. FIGS. 14B and 15B schematically show the openings 131 and 132 and the open space 126 provided in the intermediate wall portion 51. The state in which the openings 131 and 132 are connected via the open space 126 corresponds to the state in which the compression chambers A4 and A5 are communicating with each other.

As shown in FIGS. 14A and 14B, the vane 100 does not enter into the front housing chamber A2 in the circumstance in which the vane 100 contacts the second front flat surface 72 and the first rear flat surface 91. In this case, the number of the front compression chamber A4 is one, the front compression chamber A4 is filled with the suction fluid, and the front compression chamber A4 reaches the maximum volume.

In contrast, since a part of the vane 100 enters into the rear housing chamber A3, in the rear housing chamber A3, two rear compression chambers A5 (a first rear compression chamber A5a and a second rear compression chamber A5b) are formed at either side of the vane 100. The first rear compression chamber A5a and the second rear compression chamber A5b are divided by the contacting part between the second rear flat surface 92 and the second wall surface 53 and the vane 100, and adjacent to each other in the circumferential direction.

The first rear compression chamber A5a communicates with the rear side opening 132, and does not communicate with the discharge port 113. The second rear compression chamber A5b communicates with the discharge port 113, and does not communicate with the rear side opening 132. The vane 100 divides the first rear compression chamber A5a communicating with the rear side opening 132 and the second rear compression chamber A5b communicating with the discharge port 113, so that the rear side opening 132 does not directly communicate with the discharge port 113.

Thereafter, when the rotary shaft 12 is rotated by the electric motor 13, the rotors 60 and 80 are rotated. Then, the vane 100 is moved in the axial direction Z (the left and right directions in FIG. 14), and a part of the vane 100 enters into the front housing chamber A2. Accordingly, as shown in FIG. 15B, two front compression chambers A4 (a first front compression chamber A4a and second front compression chamber A4b) are formed in either side of the vane 100. The first front compression chamber A4a and the second front compression chamber A4b are divided by the contacting part of the second front flat surface 72 and the first wall surface 52 and vane 100, and adjacent to each other in the circumferential direction.

The first front compression chamber A4a communicates with the introduction port 111, and does not communicate with the front-side opening 131. The second front compression chamber A4b communicates with the front-side opening 131, and does not communicates with the introduction port 111. The vane 100 divides the first front compression chamber A4a communicating with the introduction port 111, and the second front compression chamber A4b communicating with the front-side opening 131, so that the introduction port 111 and the front-side opening 131 do not directly communicate with each other.

When the rotors 60 and 80 are rotated in this state, the volumes of the compression chambers A4 and A5 are changed. In the first front compression chamber A4a, the volume is increased and the suction fluid is drawn in from the introduction port 111, and, in the second front compression chamber A4b, the volume is decreased and the suction fluid is compressed. Similarly, in the second rear compression chamber A5b, the volume is decreased and the fluid is compressed. In contrast, in the first rear compression chamber A5a, the space itself becomes large. However, since the communication mechanism 120 is in the non-communicating state, the fluid does not flow into the first rear compression chamber A5a.

Thereafter, as shown in FIGS. 15A and 15B, after the vane 100 passes the first front flat surface 71 and the second rear flat surface 92, the compression chambers A4 and A5 (the second front compression chamber A4b and the first rear compression chamber A5a) communicate with each other. Accordingly, an intermediate pressure fluid having a higher pressure than the suction fluid compressed in the second front compression chamber A4b is introduced into the first rear compression chamber A5a. That is, the communication passage 130 communicates between the second front compression chamber A4b and the first rear compression chamber A5a.

Thereafter, when the rotors 60 and 80 are rotated to the position at which the vane 100 contacts the second front flat surface 72 and the first rear flat surface 91, all the intermediate pressure fluid in the second front compression chamber A4b is introduced into the first rear compression chamber A5a, and the compression chambers A4 and A5 do not communicate with each other. In contrast, the introduced intermediate pressure fluid is compressed as the fluid of the second rear compression chamber A5b at the time of next rotations of the rotors 60 and 80, and is discharged from the discharge port 113. In this case, since the intermediate pressure fluid is further compressed in the second rear compression chamber A5b, the compressed fluid whose pressure is made higher than the intermediate pressure fluid is discharged from the discharge port 113.

By rotating the rotors 60 and 80, in the compression chambers A4 and A5, the cycle movement of suction and compression having 720 degrees as one cycle (two rotations of the rotors 60 and 80) is repeated. A two stage compression is performed in which the intermediate pressure fluid compressed in the front compression chamber A4 is compressed again in the rear compression chamber A5.

Although the description has been given by distinguishing between the front compression chambers A4a and A4b, when the fact that the cycle movement having 720 degrees as one cycle is performed in the front compression chamber A4, the first front compression chamber A4a is the front compression chamber A4 whose phase is 0 degrees to 360 degrees, the second front compression chamber A4b is the front compression chamber A4 whose phase is 360 degrees to 720 degrees. That is, the space formed by the front rotor surface 70, the first wall surface 52, and the front cylinder inner circumferential surface 43 is divided into the front compression chamber A4 whose phase is 0 degrees to 360 degrees, and the front compression chamber A4 whose phase is 360 degrees to 720 degrees by the vane 100. In other words, the vane 100 generates volume changes of the first chamber and the second chamber (the volume of the first chamber is increased, and the volume of the second chamber is decreased) with the rotations of the rotors 60 and 80, in the state where the above-described space is divided into the first chamber into which the fluid is drawn in, and the second chamber from which the fluid is discharged. The same also applies to the first rear compression chamber A5a and the second rear compression chamber A5b.

The communication passage 130 is a passage that communicates between the front compression chamber A4 having a phase of 360 degrees to 720 degrees (a compression stage) and the rear compression chamber A5 having a phase of 0 degrees to 360 degrees (a suction stage). The communication mechanism 120 makes the front compression chamber A4 having a phase of 360 degrees to 720 degrees, and the rear compression chamber A5 having a phase of 0 degrees to 360 degrees communicate with each other and not to communicate with each other.

Next, the volume changes of the compression chambers A4 and A5 is described by using FIG. 16. In FIG. 16, the broken line indicates the volume change of the front compression chamber A4, the long dashed short dashed line indicates the volume change of the rear compression chamber A5, and the continuous line indicates the substantial volume change for the combination of the compression chambers A4 and A5, that is., the volume change of the entire compressor 10, respectively. The volume changes of the compression chambers A4 and A5 are accompanied by a phase difference. As for the phase difference, the rotor surfaces 70 and 90 are curved in the axial direction Z so as to make the separation distance between them constant, and the volume changes of the compression chambers A4 and A5 are realized by one vane 100. Additionally, the phase difference is realized since the compression spaces A4 and A5 communicate with each other in the second half of the compression stage of the front compression spaces A4.

As shown in FIG. 16, the phase of the volume change of the rear compression chamber A5 is advanced compared with the volume change of the front compression chamber A4. The compressor 10 is configured such that, in the second half stage of the compression operation of the suction fluid in the front compression chamber A4, the compression chambers A4 and A5 communicate with each other, the suction of the intermediate pressure fluid into the rear compression chamber A5 is started, and the volume of the rear compression chamber A5 is increased. Therefore, as indicated by the continuous line in FIG. 16, the volume change of the entire compressor 10 forms a graph connecting the volume change of the front compression chamber A4 and the volume change of the rear compression chamber A5 to each other.

The operation of the present embodiment will now be described.

As shown in FIGS. 12 and 13, the contact lines P1 and P2 are not straight lines extending in the radial direction R, but are curved lines that are slightly curved in the circumferential direction. Accordingly, it becomes difficult for the vane 100 to be oscillated in the circumferential direction about at least one of the contact lines P1 and P2.

The above-described embodiment has the following advantages.

(1) The compressor 10 includes the rotary shaft 12, the front rotor 60 that includes the front rotor surface 70 formed into a ring shape, and that is rotated with rotation of the rotary shaft 12, and a front cylinder side wall portion 42 that includes the front cylinder inner circumferential surface 43 opposed to the front rotor outer circumferential surface 62 in the radial direction R, and that houses the front rotor 60. The compressor 10 includes the intermediate wall portion 51 that includes the first wall surface 52 opposed to the front rotor surface 70 in the axial direction Z, and the vane 100 that is inserted into the vane groove 110 formed in the intermediate wall portion 51, and that moves in the axial direction Z with rotation of the front rotor 60. The compressor 10 includes the front compression chamber A4 that is defined by the front rotor surface 70, the first wall surface 52 and the front cylinder inner circumferential surface 43, and in which the volume is changed by the vane 100 with rotation of the front rotor 60, and the suction and compression of the fluid are performed.

The vane 100 includes the first vane end 101 that is an end in the axial direction Z and contacts the front rotor surface 70. The first vane end 101 is curved so as to be convex toward the front rotor surface 70, and extends in the direction perpendicular to the axial direction Z. The front rotor surface 70 includes the front curving surface 73 that is displaced and curved in the axial direction Z in accordance with its angular position.

The front curving surface 73 includes the front concave surface 74 that is curved in the axial direction Z so as to be concave toward the first wall surface 52, and the front convex surface 75 that is curved in the axial direction Z so as to be convex toward the first wall surface 52. The front concave surface 74 is formed such that the radius of curvature of the front concave surface radially inner ends 74a, which are the opposite ends in the radial direction R of the front concave surface 74, becomes smaller than the radius of curvature of the front concave surface radially outer end 74b. The front convex surface 75 is formed such that the radius of curvature of the front convex surface radially inner ends 75a, which are the opposite ends in the radial direction R of the front convex surface 75, becomes smaller than the radius of curvature of the front convex surface radially outer end 75b.

With this configuration, the front contact line P1, which is the contact part between the first vane end 101 and the front rotor surface 70, is easily made into a curved shape. Accordingly, compared with the configuration in which the front contact line P1 has a linear shape, it becomes more difficult for the vane 100 to be oscillated about the front contact line P1.

More particularly, when the first vane end 101 of the vane 100 that is not rotated with rotation of the front rotor 60 is contacting the front rotor surface 70, the vane 100 is likely to be oscillated about the front contact line P1.

In contrast, the radii of curvature of the front concave surface radially inner end 74a and the front concave surface radially outer end 74b are changed, and the radii of curvature of the front convex surface radially inner end 75a and the front convex surface radially outer end 75b are changed, so that the front contact line P1 becomes a curved line. Accordingly, the posture of the vane 100 is more stabilized, and it becomes more difficult for the vane 100 to be oscillated than in the case where the front contact line P1 is a straight line. Accordingly, it is possible to suppress the noise, the vibration, and the leakage of the fluid due to the oscillation of the vane 100.

The leakage of the fluid due to the oscillation of the vane 100 is, for example, the leakage of the fluid from the boundary part between the first vane end 101 and the front rotor surface 70. Particularly, via the above-described boundary part, the leakage of the fluid from the second chamber (the second front compression chamber A4b or the second rear compression chamber A5b) in which compression is performed to the first chamber (the first front compression chamber A4a or the first rear compression chamber A5a) in which suction is performed can be considered.

(2) The vane 100 is inserted into the vane groove 110. Accordingly, it is possible to regulate the rotation in the circumferential direction of the vane 100 by the contact between the vane 100 and the vane groove 110. The vane 100 is inserted into the vane groove 110 so as to be movable in the axial direction Z. In order to smoothly perform the movement of the vane 100 in the axial direction Z, a slight gap (clearance) is provided between the vane 100 and the vane groove 110. Therefore, the vane 100 may be oscillated in the vane groove 110. In this regard, according to the present embodiment, it is possible to suppress the oscillation of the vane 100 in the vane groove 110 by making the front contact line P1 into a curved shape. Accordingly, it is possible to suppress the oscillation of the vane 100 in the vane groove 110, while smoothly performing the movement of the vane 100 in the axial direction Z.

(3) The vane 100 has a plate-like shape having a thickness in the direction perpendicular to both of the axial direction Z and the longitudinal direction of the first vane end 101. The vane thickness D is set such that the vane end 101 contacts the curving surface 73 from the radially inner end to the radially outer end irrespective of the angular position of the front rotor 60. With this configuration, irrespective of the angular position of the front curving surface 73, the state is maintained where the first vane end 101 is contacting from the radially inner end to the radially outer end of the front curving surface 73. Accordingly, it becomes difficult for a part to be generated at which the first vane end 101 does not contact the front curving surface 73, while making the front contact line P1 into a curved shape. Therefore, it is possible to suppress the leakage of the fluid from the boundary part between the first vane end 101 and the front curving surface 73.

As already described, the radially inner end of the front curving surface 73 is most concaved with respect to the radially outer end at the inflection point θm. In view of this point, the vane thickness D may be set such that the first vane end 101 contacts the radially inner end of the front curving surface 73, when the vane 100 is arranged at the angular position corresponding to the inflection point θm. Accordingly, irrespective of the angular position of the front rotor 60, it is expected that the first vane end 101 contacts the front curving surface 73 from the radially inner end to the radially outer end.

(4) The front rotor surface 70 includes the first front flat surface 71 that is separated from the first wall surface 52, and the second front flat surface 72 that is separated in the circumferential direction from the first front flat surface 71, and that contacts the first wall surface 52. The front curving surface 73 connects the front flat surfaces 71 and 72 to each other, and is curved in the axial direction Z so as to be gradually closer to the first wall surface 52 from the first front flat surface 71 toward the second front flat surface 72. The front concave surface 74 is arranged closer to the first front flat surface 71 than the second front flat surface 72, and the front convex surface 75 is arranged closer to the second front flat surface 72 than the first front flat surface 71. The front concave surface 74 is connected to the front convex surface 75.

In accordance with this configuration, the difference between the radially inner end and radially outer end of the front curving surface 73 is maximized in the boundary part between the front concave surface 74 and the front convex surface 75, and the difference gradually becomes smaller toward the front flat surfaces 71 and 72. Accordingly, it is possible to make the connection position (near the angular positions θ1, θ2) between the front curving surface 73 and the front flat surfaces 71 and 72 into a smooth curved surface. Accordingly, it is possible to smoothly slide the front rotor surface 70 and the first vane end 101 with rotation of the front rotor 60.

(5) Especially, it is possible to divide, by the contact position between the second front flat surface 72 and the first wall surface 52, and the vane 100, the front compression chamber A4 (the first front compression chamber A4a) in which the suction is performed, from the front compression chamber A4 (the second front compression chamber A4b) in which the compression is performed. Accordingly, it is possible to suppress the leakage of the fluid between the first and second front compression chambers A4a and A4b, and the efficiency is improved.

(6) The compressor 10 includes the rear rotor 80 that is rotated with the rotation of rotary shaft 12, and the rear cylinder side wall portion 55 that includes the rear cylinder inner circumferential surface 56 opposed to the rear rotor outer circumferential surface 82 in the radial direction R, and that houses the rear rotor 80. The rear rotor 80 includes the rear rotor surface 90 that are opposed to the front rotor surface 70 in the axial direction Z, and that is formed into a ring shape. The intermediate wall portion 51 is arranged between the rotors 60 and 80, and includes the second wall surface 53 opposed to the rear rotor surface 90 in the axial direction Z. The vane 100 includes the second vane end 102 contacting the rear rotor surface 90. The compressor 10 includes the rear compression chamber A5 that is defined by the rear rotor surface 90, the second wall surface 53 and the rear cylinder inner circumferential surface 56, and in which the volume is changed by the vane 100 with rotation of the rear rotor 80, and the suction and compression of the fluid are performed.

The rear rotor surface 90 includes the rear curving surface 93 including the rear concave surface 94 and the rear convex surface 95 as the second concave surface and the second convex surface. The front concave surface 74 and the rear convex surface 95 are opposed to each other in the axial direction Z, and the front convex surface 75 and the rear concave surface 94 are opposed to each other in the axial direction Z. Additionally, the curving surfaces 73 and 93 have the inflection points θm at an identical angle position, and are inclined such that the radially inner ends of the curving surfaces 73 and 93 are more separated from each other than the radially outer ends at least at the inflection points θm. That is, at least at the inflection points θm, the distance between the radially inner ends of the curving surfaces 73 and 93 is larger than the distance between the radially outer ends. Then, when the vane 100 is arranged at the angular position corresponding to the inflection point θm, the vane ends 101 and 102 contact the radially inner ends of the curving surfaces 73 and 93.

With this configuration, when the rotors 60 and 80 are rotated, the vane 100 is moved in the axial direction Z in the state where the vane ends 101 and 102 are contacting the rotor surfaces 70 and 90, and the suction and compression of the fluid are performed in the compression chambers A4 and A5. Accordingly, it is possible to perform the suction and compression of the fluid in the compression chambers A4 and A5, without providing the vane 100 corresponding to each of the compression chambers A4 and A5.

Additionally, with the present embodiment, in the concave surfaces 74 and 94, the radius of curvature of the radially inner end is smaller than the radius of curvature of the radially outer end, and in the convex surfaces 75 and 95, the radius of curvature of the radially inner end is smaller than the radius of curvature of the radially outer end. Accordingly, since both contact lines P1 and P2, which are the contact lines between the curving surfaces 73 and 93 and the vane ends 101 and 102, can be made into curved shapes, it is possible to more preferably suppress the oscillation of the vane 100.

By configuring the curving surfaces 73 and 93 as described above, the radially inner ends of the curving surfaces 73 and 93 are more separated from each other than the radially outer ends at least at the inflection points θm. In this regard, with the present embodiment, when the vane 100 is arranged at the angular position corresponding to the inflection point θm, the vane ends 101 and 102 contact the radially inner ends of the curving surfaces 73 and 93. Accordingly, it becomes difficult for a gap to be produced between the vane ends 101 and 102 and the curving surfaces 73 and 93, while making both contact lines P1 and P2 into curved shapes.

(7) The rear rotor surface 90 includes the rear flat surfaces 91 and 92 arranged at positions mutually shifted in the axial direction Z. The second rear flat surface 92 contacts the second wall surface 53. The rear curving surface 93 connects the rear flat surfaces 91 and 92. The first front flat surface 71 and the second rear flat surface 92 are opposed to each other, and the second front flat surface 72 and the first rear flat surface 91 are opposed to each other. With this configuration, since the first rear flat surface 91 is arranged at the position opposed to the second front flat surface 72, the separation distance between them becomes constant, and a trouble hardly occurs in the movement of the vane 100, and a gap between the vane 100 and the rotor surfaces 70 and 90 is hardly generated. The same also applies to the rear compression chamber A5.

(8) The front rotor surface 70 includes the second front flat surface 72 as a contact surface that is contacting the first wall surface 52. The pair of front curving surfaces 73 are provided on the opposite sides in the circumferential direction of the rotary shaft 12 with respect to the second front flat surface 72. The pair of front curving surfaces 73 are each curved to the axial direction Z so as to be gradually separated from the second front flat surface 72, as the front curving surfaces 73 are separated from the second front flat surface 72 in the circumferential direction. Also, the pair of front curving surfaces 73 are formed such that the front contact line P1, which is the contact line with the first vane end 101, is bent in the circumferential direction. That is, the pair of front curving surfaces 73 are formed such that the curvature of the displacement curve in the axial direction Z with respect to the angular change differs in accordance with the position in the radial direction R. With this configuration, the advantage of (1) is produced.

The above-described embodiment may be modified as follows. The above-described embodiment and the following modifications can be combined as long as the combined modifications remain technically consistent with each other.

The rear rotor 80 may have a larger diameter than the front rotor 60.

Although the rotors 60 and 80 have different diameters, this is not a limitation, and may have the same diameter. That is, the volumes of the compression chambers A4 and A5 may be the same.

The front flat surfaces 71 and 72 and the rear flat surfaces 91 and 92 may be omitted. That is, the entire rotor surfaces 70 and 90 may be curving surfaces.

The first vane end 101 and the front rotor surface 70 are not limited to the configuration in which they contact each other over the entire part from the radially inner end to the radially outer end, and may be configured to contact each other over a partial range in the radial direction. Additionally, the first vane end 101 and the front rotor surface 70 are not limited to the configuration in which they contact each other over the entire circumference, and may be configured to contact each other over a partial angular range. The same applies to the second vane end 102 and the rear rotor surface 90.

The number of the vane 100 is arbitrary, and may be plural, for example. Additionally, the circumferential direction position of the vane 100 is arbitrary.

The shapes of the vane 100 and the vane groove 110 are not limited to those in each of the embodiments, as long as the shapes allow the movement of the vane 100 in the axial direction Z, while the movement in the circumferential direction is restricted. For example, the vane may have a sectoral shape.

Additionally, the vane may be configured to move in the axial direction Z like a pendulum that moves about a predetermined place. That is, the vane may be configured to move in the axial direction Z in accordance with rotational movement, and not limited to linear movement.

The specific shapes of the cylinders 40 and 50 are arbitrary. For example, the bulged part 46 may be omitted. Additionally, though the cylinders 40 and 50 are different bodies, they may be integrally formed.

Similarly, the specific shapes of the housings 21 and 22 are also arbitrary.

The cylinders 40 and 50 may be omitted. In this case, the inner circumferential surface of the housing 11 may form the compression chambers A4 and A5. In this configuration, the housing 11 corresponds to the first cylindrical portion and the second cylindrical portion.

The electric motor 13 and the inverter 14 may be omitted. That is, the electric motor 13 and the inverter 14 are not essential in the compressor 10

The rotors 60 and 80 may be each fixed to the rotary shaft 12 so as to be integrally rotated with the rotary shaft 12, or only one of the rotors 60 and 80 may be attached to the rotary shaft 12 to be integrally rotated with the rotary shaft 12, and the other may be attached to the rotary shaft 12 to be rotatable with respect to the rotary shaft 12. Even in this case, since the rotary valves 122 and 124 are engaged with each other in the circumferential direction, with the rotation of one of the rotors 60 and 80, the other is also rotated.

The outer circumferential surfaces of the boss portions 121 and 123 are not flush, and may have stepped shapes. In this case, the inner end face 103 of the vane 100 may similarly have a stepped shape, so that a gap is not formed.

As shown in FIGS. 17 and 18, the communication mechanism 200 may be formed so as to bypass the intermediate wall portion 51. For example, the communication mechanism 200 may communicate the front compression chamber A4 with the rear compression chamber A5 via the communication passage 201 formed in the cylinder side wall portions 42 and 55. The communication passage 201 includes a front-side opening formed in the part that forms the second front compression chamber A4b of the front cylinder inner circumferential surfaces 43, and a rear side opening in the part that forms the first rear compression chamber A5a of the rear cylinder inner circumferential surfaces 56, and connects these openings to each other. In this case, the communication mechanism 200 is switched to the non-communicating state when the phase of the front compression chamber A4 is 0 degrees to 360 degrees, and to the communicating state when the phase of the front compression chamber A4 is 360 degrees to 720 degrees.

In this case, the boss portions 121 and 123 and the rotary valves 122 and 124 may be omitted. That is, it is not essential that the rotors 60 and 80 contact or engage with each other.

In this configuration, the diameter of the wall through-hole 54 may be reduced, so that the wall inner circumferential surface 54a and the rotary shaft 12 contact or are close to each other. Additionally, the inner end face 103 of the vane 100 may directly contact the rotary shaft 12.

The communication groove 133 may communicate with both openings 131 and 132. In this case, the connecting valve 125 may have a fully closed ring shape in which the open space 126 is not formed. That is, the configuration may be adopted in which the rotary valves 122 and 124 are formed in the entire circumference in the engaged state. Additionally, when the communication groove 133 communicates with both openings 131 and 132, the configuration may be adopted in which the rotary valves 122 and 124 are omitted, and the boss tip surfaces 121a and 123a directly contact each other. That is, the rotary valves 122 and 124 are not essential. Even in this case, the communication mechanism 120 can be said to be in the non-communicating state when the phase of the front compression chamber A4 is 0 to 360 degrees, and is switched to the communicating state when the phase is 360 to 720 degrees.

As long as the rotary valves 122 and 124 are engaged with each other in the circumferential direction, the specific engagement manner is arbitrary. For example, two rear rotary valves 124 may be provided, and the front rotary valve 122 may be arranged between the rear rotary valves 124.

As long as the openings 131 and 132 are mutually separated in the circumferential direction, their specific positions are arbitrary.

Only one of the front concave surface 74 and the front convex surface 75, and the rear concave surface 94 and the rear convex surface 95 may be configured to produce a curvature change. That is, at least one of the contact lines P1 and P2 may have a curved shape.

The compression chambers A4 and A5 do not necessarily need to communicate with each other. That is, the communication mechanism 120 may be omitted. In this case, the compressor 10 may be configured such that, in each of the compression chambers A4 and A5, the suction fluid is drawn in, and the compressed fluid is discharged. For example, a discharge port may be provided in the front rotor 60, and the compressed fluid may be discharged from the discharge port, or a suction port may be provided in the rear rotor 80, and the suction fluid may be introduced from the suction port.

One of the rotors 60 and 80 may be omitted. For example, as shown in FIG. 19, the front rotor 60 may be omitted. In this case, the front compression chamber A4 is also omitted. That is, the two rotors and the two compression chambers are not essential.

In this configuration, the suction port 211 may be formed in the intermediate wall portion 51 so that the suction fluid is introduced into the rear compression chamber A5. Additionally, an energizing part 212 for urging the vane 100 to the rear rotor surface 90 may be provided. With this configuration, the vane 100 is moved in the axial direction Z while sliding on the rear rotor surface 90 with rotation of the rear rotor 80. Accordingly, the volume change is caused in the rear compression chamber A5, and the suction and compression of the suction fluid are performed in the rear compression chamber A5.

Further, when the front rotor 60 is omitted, the length in the radial direction R of the vane 100 may be the same as the length in the radial direction R of the rear rotor surface 90. In this case, the vane groove 110 may be formed only in the intermediate wall portion 51, and does not necessarily need to be formed in the rear cylinder side wall portion 55.

Additionally, in this modification, the inner end face 103 of the vane 100 may contact the rotary shaft 12 (particularly, the outer circumferential surface of the rotary shaft 12). Additionally, when the front rotor 60 is omitted, the first rear flat surface 91 may be omitted.

FIGS. 20 and 21 shows the inner end face 103 of the vane 100 curved so as to be concave toward the outside in the radial direction R and the outer circumferential surface of the front boss portion 121 curved so as to be convex toward the outside in the radial direction R. As shown in FIGS. 20 and 21, the curvature of the inner end face 103 of the vane 100 may be smaller than the curvature of the outer circumferential surface of the front boss portion 121. That is, the inner end face 103 of the vane 100 may be concave to the outside in the radial direction R, and may be more gently curved than the outer circumferential surface of the front boss portion 121.

With this configuration, it is possible to prevent the curvature of the inner end face 103 of the vane 100 from becoming larger than the curvature of the outer circumferential surface of the front boss portion 121 due to a manufacturing error, and the like. Accordingly, it is possible to suppress the inconvenience caused by the curvature of the inner end face 103 of the vane 100 becoming larger than the curvature of the outer circumferential surface of the front boss portion 121.

More particularly, if the curvature of the inner end face 103 of the vane 100 is made the same as the curvature of the outer circumferential surface of the front boss portion 121, the curvature of the inner end face 103 of the vane 100 may become larger than the curvature of the outer circumferential surface of the front boss portion 121 because of a manufacturing error, and the like. In this case, when both ends of the inner end face 103 of the vane 100 are caught in the outer circumferential surface of the front boss portion 121, hindering the movement in the axial direction Z of the vane 100 or wearing the inner end face 103 of the vane 100 from both ends.

In this regard, with this modification, by positively curving the inner end face 103 of the vane 100 more gently than the outer circumferential surface of the front boss portion 121, even when a manufacturing error and the like occurs, it is possible to prevent the curvature of the inner end face 103 of the vane 100 from becoming larger than the curvature of the outer circumferential surface of the front boss portion 121. Accordingly, it is possible to suppress the inconvenience caused by the curvature of the inner end face 103 of the vane 100 becoming larger than the curvature of the outer circumferential surface of the front boss portion 121.

Additionally, since the inner end face 103 of the vane 100 is more gently curved than the outer circumferential surface of the front boss portion 121, a gap is generated in the second front compression chamber A4b between the inner end face 103 of the vane 100 and the outer circumferential surface of the front boss portion 121. In the second front compression chamber A4b, the compressed fluid flows into the gap between the inner end face 103 of the vane 100 and the outer circumferential surface of the front boss portion 121. The compressed fluid presses the vane 100 toward the outer side in the radial direction R, so that the gap between the outer end face 104 of the vane 100 and the front cylinder inner circumferential surface 43 is sealed.

Incidentally, the outer circumferential surface of the front boss portion 121 is flush with the outer circumferential surface of the rear boss portion 123. It thus can also be said that the curvature of the inner end face 103 of the vane 100 is smaller than the curvature of the outer circumferential surface of the rear boss portion 123. Similarly, the outer circumferential surfaces of the boss portions 121 and 123 are flush with the valve outer circumferential surface 125a. It thus can also be said that the curvature of the inner end face 103 of the vane 100 is smaller than the curvature of the valve outer circumferential surface 125a.

Since the rotary shaft 12 is inserted through (in other words, inserted into) the boss portions 121 and 123, it can be said that the boss portions 121 and 123 (and the connecting valve 125) is a rotor cylindrical portion that is rotated with rotation of the rotary shaft 12. In this case, it can also be said that the curvature of the inner end face 103 of the vane 100 is smaller than the curvature of the outer circumferential surface of the rotor cylindrical portion.

Further, as in the modification shown in FIG. 19, when the inner end face 103 of the vane 100 is caused to contact the outer circumferential surface of the rotary shaft 12, the curvature of the inner end face 103 of the vane 100 is preferably smaller than the curvature of the outer circumferential surface of the rotary shaft 12 curved so as to be convex toward the outside in the radial direction R.

FIG. 20 shows the outer end face 104 of the vane 100 curved so as to be convex toward the outside in the radial direction R and the front cylinder inner circumferential surface 43 of the front cylinder 40 curved so as to be convex toward the outside in the radial direction R. As shown in FIG. 20, the curvature of the outer end face 104 of the vane 100 may be greater than the curvature of the front cylinder inner circumferential surface 43 of the front cylinder 40. That is, the outer end face 104 of the vane 100 may be convex toward the outside in the radial direction R, and may be more greatly curved than the front cylinder inner circumferential surface 43.

With this configuration, it is possible to prevent the curvature of the outer end face 104 of the vane 100 from becoming smaller than the curvature of the front cylinder inner circumferential surface 43 due to a manufacturing error, and the like.

More particularly, if the curvature of the outer end face 104 of the vane 100 is made the same as the curvature of the front cylinder inner circumferential surface 43, the curvature of the outer end face 104 of the vane 100 may become smaller than the curvature of the front cylinder inner circumferential surface 43 because of a manufacturing error, and the like. In this case, when both ends of the outer end face 104 of the vane 100 are caught in the front cylinder inner circumferential surface 43, hindering the movement in the axial direction Z of the vane 100 or wearing the outer end face 104 of the vane 100 from both ends.

In this regard, with this modification, by positively curving the outer end face 104 of the vane 100 more greatly than the front cylinder inner circumferential surface 43, even when a manufacturing error and the like occurs, it is possible to prevent the curvature of the outer end face 104 of the vane 100 from becoming smaller than the curvature of the front cylinder inner circumferential surface 43. Accordingly, it is possible to suppress the inconvenience caused by the curvature of the outer end face 104 of the vane 100 becoming smaller than the curvature of the front cylinder inner circumferential surface 43.

Additionally, since the outer end face 104 of the vane 100 is more greatly curved than the front cylinder inner circumferential surface 43, a gap is generated in the second front compression chamber A4b between the outer end face 104 of the vane 100 and the front cylinder inner circumferential surface 43. In the second front compression chamber A4b, the compressed fluid flows into the gap between the outer end face 104 of the vane 100 and the front cylinder inner circumferential surface 43. The compressed fluid presses the vane 100 toward the inner side in the radial direction R, so that the gap between the inner end face 103 of the vane 100 and the outer circumferential surface of the front boss portion 121 is sealed.

The curvature of the inner end face 103 of the vane 100 may be same as the curvature of the outer circumferential surface of the front boss portion 121, and the curvature of the outer end face 104 of the vane 100 may be greater than the curvature of the front cylinder inner circumferential surface 43. Also, the curvature of the inner end face 103 of the vane 100 may be smaller than the curvature of the outer circumferential surface of the front boss portion 121, and the curvature of the outer end face 104 of the vane 100 may be the same as the curvature of the front cylinder inner circumferential surface 43.

As shown in FIG. 22, in the outer end face 104 of the vane 100, the curvatures are different between the part where the first front compression chamber A4a is disposed and the part where the second front compression chamber A4b is disposed. Particularly, the outer end face 104 of the vane 100 may include a first outer end face 221 that is provided on the first front compression chamber A4a (leading side in the rotation direction) and has a curvature larger than the curvature of the front cylinder inner circumferential surface 43, and a second outer end face 222 that is provided on the second front compression chamber A4b (on the trailing side in the rotation direction) and has a curvature larger than the curvature of the first outer end face 221. The first outer end face 221 is on the leading side in the rotation direction of the second outer end face 222. This configuration improves the sealing property in addition to the above-described advantages.

More particularly, with this modification, the curvature of the first outer end face 221 is closer to the curvature of the front cylinder inner circumferential surface 43 than the curvature of the second outer end face 222. Thus, the contact part between the first outer end face 221 and the front cylinder inner circumferential surface 43 is easily extended in the circumferential direction, increasing the contact area between the first outer end face 221 and the front cylinder inner circumferential surface 43. This improves the sealing property between the outer end face 104 of the vane 100 and the front cylinder inner circumferential surface 43.

In contrast, the second outer end face 222 in the second front compression chamber A4b is more greatly curved than the first outer end face 221. Thus, a gap is easily formed in the second front compression chamber A4b between the second outer end face 222 and the front cylinder inner circumferential surface 43. Accordingly, the compressed fluid easily enters between the second outer end face 222 and the front cylinder inner circumferential surface 43. Since the compressed fluid presses the vane 100 toward the inner side in the radial direction R, the sealing property between the inner end face 103 of the vane 100 and the outer circumferential surface of the front boss portion 121 is improved.

The vane 100 may be formed by multiple components. For example, the vane 100 may include a vane body that is inserted into the vane groove 110 and a front tip seal that is provided between the vane body and the front rotor surface 70 and contacts the front rotor surface 70. In this case, the front tip seal or an end of the front tip seal forms an end in the axial direction Z of the vane 100 and corresponds to a vane end.

Likewise, the vane 100 may include a rear tip seal that is provided between the vane body and the rear rotor surface 90 and contacts the rear rotor surface 90. In this case, the rear tip seal or an end of the rear tip seal corresponds to a vane end.

The compressor 10 may be used for devices other than an air-conditioner. For example, the compressor 10 may be used to supply compressed air to a fuel cell mounted in a fuel cell vehicle.

The compressor 10 may be mounted on any structure other than a vehicle.

The fluid to be compressed by the compressor 10 is not limited to refrigerant including oil, and is arbitrary.

Claims

1. The compressor according to claim 10, wherein

the curving surface includes a concave surface curved in the axial direction so as to be concave toward the wall surface, and a convex surface curved in the axial direction so as to be convex toward the wall surface,

the concave surface includes a concave surface radially inner end and a concave surface radially outer end as opposite ends in the radial direction,

in the concave surface, a radius of curvature of the concave surface radially inner end in the axial direction is smaller than a radius of curvature of the concave surface radially outer end,

the convex surface includes a convex surface radially inner end and a convex surface radially outer end as opposite ends in the radial direction, and

in the convex surface, a radius of curvature of the convex surface radially inner end in the axial direction is smaller than a radius of curvature of the convex surface radially outer end.

2. The compressor according to claim 1, wherein

the vane includes a tabular shape having a thickness in a direction perpendicular to both the axial direction and the longitudinal direction of the vane end, and

the thickness of the vane is set such that the vane end contacts the curving surface from a radially inner end to a radially outer end irrespective of the angular position of the curving surface.

3. The compressor according to claim 1, wherein

the rotor surface includes a first flat surface and a second flat surface that are perpendicular to the axial direction,

the first flat surface is separated from the wall surface in the axial direction,

the second flat surface is provided at a position separated from the first flat surface in a circumferential direction and contacts the wall surface,

the curving surface connects the first flat surface to the second flat surface and is curved in the axial direction so as to be gradually closer to the wall surface from the first flat surface toward the second flat surface,

the concave surface is arranged closer to the first flat surface than the second flat surface,

the convex surface is arranged closer to the second flat surface than the first flat surface, and

the concave surface is connected to the convex surface.

4. The compressor according to claim 1, comprising:

as the rotor, a first rotor and a second rotor that are arranged to be opposed to each other in the axial direction,

as the cylindrical portion, a first cylindrical portion and a second cylindrical portion, wherein the first cylindrical portion includes a first inner circumferential surface opposed to the outer circumferential surface of the first rotor in the radial direction and houses the first rotor, and the second cylindrical portion includes a second inner circumferential surface opposed to the outer circumferential surface of the second rotor in the radial direction and houses the second rotor, and

as the compression chamber, a first compression chamber and a second compression chamber, wherein

the first rotor includes a first rotor surface as the rotor surface,

the second rotor includes, as the rotor surface, a second rotor surface opposed to the first rotor surface in the axial direction,

the vane is arranged between the rotor surfaces and includes, as the vane end, a first vane end contacting the first rotor surface and a second vane end contacting the second rotor surface,

the wall portion is arranged between the first rotor and the second rotor and includes, as the wall surface, a first wall surface opposed to the first rotor surface in the axial direction and a second wall surface opposed to the second rotor surface in the axial direction,

the first compression chamber is defined by the first rotor surface, the first wall surface, and the first inner circumferential surface, and is a chamber in which volume change is caused by the vane with rotation of the first rotor such that suction and compression of the fluid are performed,

the second compression chamber is defined by the second rotor surface, the second wall surface, and the second inner circumferential surface, and is a chamber in which volume change is caused by the vane with rotation of the second rotor such that suction and compression of the fluid are performed,

the first rotor surface includes a first curving surface including a first concave surface and a first convex surface that are connected to each other,

the second rotor surface includes, as the curving surface, a second curving surface including a second concave surface and a second convex surface that are connected to each other,

the first concave surface and the second convex surface are opposed to each other in the axial direction,

the first convex surface and the second concave surface are opposed to each other in the axial direction,

the first curving surface and the second curving surface include inflection points at an identical angle position and are inclined such that the radially inner ends of the curving surfaces are more separated from each other than the radially outer ends at least at the inflection point, and

when the vane is arranged at an angular position corresponding to the inflection point, the first vane end contacts a radially inner end of the first curving surface, and the second vane end contacts a radially inner end of the second curving surface.

5. The compressor according to claim 1, wherein

the concave surface is formed such that the radius of curvature in the axial direction gradually becomes smaller from the concave surface radially outer end toward the concave surface radially inner end, and

the convex surface is formed such that the radius of curvature in the axial direction gradually becomes smaller from the convex surface radially outer end toward the convex surface radially inner end.

6. The compressor according to claim 1, wherein

a radially inside end face of the vane contacts an outer circumferential surface of the rotor cylindrical portion into which the rotary shaft is inserted and that is rotated with rotation of the rotary shaft, and

a curvature of the radially inside end face of the vane is smaller than a curvature of the outer circumferential surface of the rotor cylindrical portion.

7. The compressor according to claim 1, wherein

a radially inside end face of the vane contacts an outer circumferential surface of the rotary shaft, and

a curvature of the radially inside end face of the vane is smaller than a curvature of the outer circumferential surface of the rotary shaft.

8. The compressor according to claim 1, wherein

a radially outside end face of the vane contacts the inner circumferential surface of the cylindrical portion, and

a curvature of the radially outside end face of the vane is larger than a curvature of the inner circumferential surface of the cylindrical portion.

9. The compressor according to claim 8, wherein the radially outside end face of the vane includes

a first outer end face that is arranged on a leading side in the rotation direction of the rotary shaft and has a curvature larger than the curvature of the inner circumferential surface of the cylindrical portion, and

a second outer end face that is arranged on a trailing side in the rotation direction of the rotary shaft and has a curvature larger than the curvature of the first outer end face.

10. A compressor comprising:

a rotary shaft;

a rotor including a rotor surface formed into a ring-shape and rotated with rotation of the rotary shaft;

a cylindrical portion including an inner circumferential surface opposed to an outer circumferential surface of the rotor in a radial direction of the rotary shaft, and housing the rotor;

a wall portion including a wall surface opposed to the rotor surface in an axial direction of the rotary shaft;

a vane that is inserted into a vane groove formed in the wall portion, and is moved in the axial direction with rotation of the rotor; and

a compression chamber defined by the rotor surface, the wall surface, and the inner circumferential surface of the cylindrical portion, and volume change of the compression chamber being caused by the vane with rotation of the rotor such that suction and compression of fluid are performed, wherein

the vane includes a vane end that is an end in the axial direction and contacts the rotor surface,

the vane end is curved so as to be convex toward the rotor surface and extends in a direction perpendicular to the axial direction,

the rotor surface includes a curving surface curved in the axial direction,

the curving surface is curved so as to be displaced in the axial direction in accordance with its angular position, and

the curving surface includes a part in which a radius of curvature with respect to the axial direction differs in accordance with a position in the radial direction such that at least a part of a contact line between the curving surface and the vane end is curved in a circumferential direction of the rotor.