COMPRESSOR

Abstract

A compressor includes a discharge chamber, a compression chamber, a partition wall, and a discharge reed valve. The partition wall is arranged between the discharge chamber and the compression chamber and includes a fixing surface that faces the discharge chamber. The partition wall includes a discharge port that can communicate the discharge chamber and the compression chamber. The discharge reed valve includes a fixed portion, an intermediate portion, and a valve portion. The partition wall includes a supporting portion, a receiving portion, and a main coupling portion. The supporting portion supports a central region of the valve portion. The receiving portion receives a distal region of the valve portion. The main coupling portion extends from the supporting portion to couple the supporting portion and the receiving portion in order to divide into two a distal discharging region of the discharge port.

Description

TECHNICAL FIELD

The present invention relates to a compressor.

BACKGROUND ART

The following compressor is known (e.g., patent document 1). In this compressor, a valve plate is arranged between a discharge chamber and a compression chamber. A discharge port, which extends through the valve plate, can communicate the discharge chamber and the compression chamber. A discharge reed valve, which is located in the discharge chamber, opens and closes the discharge port.

The discharge reed valve includes a fixed portion, which is fixed to a fixing surface that is a surface of the valve plate at a side facing the discharge chamber, an intermediate portion, which extends toward a distal side along a longitudinal direction from the fixed portion and can be lifted, and a valve portion, which extends toward the distal side along the longitudinal direction from the intermediate portion to open and close the discharge port. An annular groove that surrounds the entire circumference of the discharge port is arranged in the fixing surface. A portion of the fixing surface between the discharge port and the annular groove forms a valve seat surface that is flush with the portion of the fixing surface outward from the annular groove. In a state in which the discharge reed valve is closing the discharge port, a distal part of the valve portion extends beyond the valve seat surface in the longitudinal direction.

In this type of compressor, it is ideal that the discharge port immediately opens at the moment the difference between the pressure in the discharge chamber and the pressure in the compression chamber exceeds zero. However, when lubricating oil is present like in an actual machine, as shown in FIG. 23, an adhesive force S acts in a direction inhibiting the opening of a discharge reed valve 81. Thus, the discharge reed valve 81 does not open a discharge port 82 until a force F produced by the pressure difference prevails over the adhesive force S. In such a situation, a bore inner pressure (pressure in the compression chamber) is as shown in FIG. 24. Such a phenomenon in which the bore inner pressure becomes higher than the discharging pressure is referred to as over-compression and causes power loss. The adhesive force is produced by the oil film pressure of the lubricating oil. The oil film pressure is lower than the surrounding pressure when the discharge reed valve 81 attempts to separate from the valve plate 27. The inventors refer to this effect as a “negative squeeze effect”.

PATENT DOCUMENT

Patent Document 1: Japanese Laid-Open Patent Publication No. 11-117867

DISCLOSURE OF THE INVENTION

Such power loss leads to an increase in energy consumption. From the standpoint of reducing energy consumption, it is desirable that the power loss be further decreased.

Further, in the compressor described above, the discharge reed valve may be damaged, and it is desirable that the durability be improved.

It is an object of the present invention to provide a compressor that can further reduce power loss and exhibit higher durability.

In order to achieve the above object, the inventors have analyzed the conventional compressor in detail. As a result, the inventors have taken notice of the enlargement of the discharge port and the moment the discharge reed valve closes.

More specifically, if the discharge port has, for example, a circular shape when viewed from above, a pressure receiving area of the valve portion that opens and closes the discharge port increases in proportion to the square of the diameter of the discharge port. Thus, the force opening the discharge port increases when the discharge port is enlarged. In this case, the adhesive force of the lubricating oil that inhibits the valve opening acts on the circumferential edge of the discharge port and is thus only proportional to the diameter of the discharge port. This decreases the adhesive force when the discharge port is enlarged. Therefore, when the discharge port is enlarged, over-compression can be reduced, and power loss can be suppressed.

However, in the simulation conducted by the inventors, when the discharge port was enlarged, a central region of the valve portion was greatly bent into the discharge port due to the force of inertia or the pressure difference of the compression chamber and the discharge chamber (hereinafter referred to as “pressure difference”) during a suction stroke at the moment the discharge reed valve closes. Thus, fatigue failure is apt to occur at the valve portion. In particular, this tendency is stronger when the compressor operates at high speeds. This lowers the durability of the compressor.

In particular, in the simulation, at the valve portion, the striking against the valve seat surface starts from the side of the intermediate portion, and a stress wave is propagated toward the distal side. Thus, if the valve portion of the discharge reed valve has a circular shape when viewed from above, the valve portion extending toward the distal side along the longitudinal direction bends like a whip and strongly strikes the fixing surface. This is because the mass of the discharge reed valve increases toward the distal side along the longitudinal direction, and a large force of inertia acts on the valve portion toward the distal side in the longitudinal direction. This phenomenon becomes remarkable when the intermediate portion is rectangular with its long sides extending in the longitudinal direction and the valve portion is circular having a diameter that is larger than or equal to the short sides of the intermediate portion so that the discharge reed valve greatly opens the discharge port.

In this manner, the inventors have completed the present invention.

One aspect of the present invention provides a compressor comprising a discharge chamber, a compression chamber, a partition wall, and a discharge reed valve. The partition wall is arranged between the discharge chamber and the compression chamber and includes a fixing surface that faces the discharge chamber. The partition wall includes a discharge port that can communicate the discharge chamber and the compression chamber. The discharge reed valve has a length extending along a longitudinal direction, a distal end, and a basal end. The discharge reed valve includes a fixed portion, an intermediate portion, and a valve portion. The fixed portion is located at the basal end and fixed to the fixing surface. The intermediate portion extends from the fixed portion toward the distal end and is liftable relative to the fixing surface. The valve portion further extends from the intermediate portion toward the distal end and is capable of opening and closing the discharge port. The partition wall includes a supporting portion, a receiving portion, and a main coupling portion. The supporting portion supports a central region of the valve portion. The receiving portion receives a distal region of the valve portion. The main coupling portion extends from the supporting portion to couple the supporting portion and the receiving portion in order to divide into two a distal discharging region of the discharge port located at a distal side of the supporting portion in the longitudinal direction. The discharge port extends through the partition wall so as to leave the supporting portion, the receiving portion, and the main coupling portion in the partition wall. The receiving portion has a larger width than the supporting portion in a direction orthogonal to the longitudinal direction.

In the compressor of the present invention, when the force of inertia or the pressure difference acts to greatly bend the central region of the valve portion into the discharge port at the moment the discharge reed valve closes the central region of the valve portion, the supporting portion supports the central region of the valve portion. Further, in a preferred manner, the supporting portion, the main coupling portion, and the receiving portion support the valve portion, which strikes the fixing surface while bending like a whip toward the distal side along the longitudinal direction. This prevents fatigue failure at the valve portion.

Further, in the compressor of the present invention, the receiving portion has a larger width than the supporting portion in a direction orthogonal to the longitudinal direction. Thus, when the valve portion of the discharge reed valve strikes the receiving portion, the lubricating oil on the receiving portion reduces the striking force due to the squeeze film effect so that only a small stress acts on the valve portion, and a large stress is not produced at the distal region of the valve portion. This further prevents fatigue failure at the discharge reed valve, and the compressor can exhibit high durability. With the squeeze film effect, when a gap between parallel surfaces decreases at the velocity V, due to the viscosity of the fluid, the fluid resists being pushed out of the gap and generates pressure (proportional to viscosity coefficient and velocity V).

In the compressor, due to the operations described above, the pressure receiving area of the valve portion is increased, the force that opens the discharge port is increased by increasing the port diameter, while the increase of the adhesive force of the lubricating oil inhibiting valve opening is limited. Thus, over-compression can be decreased and power loss can be suppressed.

Accordingly, the compressor can further reduce power loss and exhibit higher durability.

Further, in the compressor, discharging pulsation can be reduced by limiting the opening delay of the discharge reed valve. This improves the quietness of the compressor. Further, in the compressor, over-compression is decreased by increasing the port diameter. Thus, exciting force, bearing load, piston side force (lateral force), and the like have a tendency of decreasing. This reduces mechanical loss and suppresses wear. As a result, power consumption can be decreased, and reliability can be improved.

Japanese Laid-Open Patent Publication No. 2009-235913 discloses a compressor including a supporting portion that divides an entire suction port into two. However, in regard with the disclosed technique of the publication, the present invention has a significant advantage in that superior effects are obtained at the discharge side, which requires capacities that can endure harsher conditions.

When the widths of the supporting portion, the main coupling portion, and the receiving portion are increased, fatigue failure of the valve portion can be prevented. In contrast, when the areas of the supporting portion, the main coupling portion, and the receiving portion are increased, the area of the discharge port is decreased. Further, an increase in the contact area of the supporting portion, the main coupling portion, and the receiving portion increases adhesive force, and the discharge port thus cannot easily open. To resolve these contradicting problems, the present invention allows for selection of the suitable size and shape of the supporting portion, the main coupling portion, and the receiving portion.

Preferably, the partition wall includes a sub-coupling portion extending from the supporting portion to divide at least into two a basal discharging region of the discharge port located at a basal side of the supporting portion in the longitudinal direction. The discharge port extends through the partition wall so as to leave the supporting portion, the receiving portion, the main coupling portion, and the sub-coupling portion in the partition wall.

In this case, the discharge port is divided into two or more port segments by the supporting portion, the receiving portion, main coupling portion, and the sub-coupling portion. This increases the strength of the supporting portion, and the valve portion that bends like a whip can easily be supported sequentially from the basal side toward the distal side in the longitudinal direction. Further, fatigue failure is effectively prevented at the valve portion.

Preferably, the sub-coupling portion extends along the longitudinal direction. The discharge port is divided into two port segments by the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion.

In this case, the advantages in which fatigue failure at the valve portion is prevented and the discharge port easily opens are obtained.

Preferably, the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion have widths that increase toward the distal side in the longitudinal direction.

In this case, the discharge port easily opens at a basal discharging region, the receiving portion receives a distal region of the valve portion in a preferred manner, and fatigue failure at the valve portion can be further prevented.

Preferably, the sub-coupling portion includes a first sub-coupling portion, which extends along the longitudinal direction, a second sub-coupling portion, which extends at an angle of 90° in a clockwise direction from the main coupling portion, and a third sub-coupling portion, which extends along at an angle of 90° in a counterclockwise direction from the main coupling portion. The discharge port is divided into four port segments by the first sub-coupling portion, the second sub-coupling portion, the third sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion.

This also easily obtains the advantages in which fatigue failure of the valve portion is prevented and the discharge port easily opens.

Preferably, the sub-coupling portion includes a first sub-coupling portion, which extends at an angle of 120° in a clockwise direction from the main coupling portion, and a second sub-coupling portion, which extends at an angle of 120° in a counterclockwise direction from the main coupling portion. The discharge port is divided into three port segments by the first sub-coupling portion, the second sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion.

This also easily obtains the advantages in which fatigue failure of the valve portion is prevented and the discharge port easily opens.

Preferably, the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion are flush with the fixing surface.

This reduces machining costs.

Preferably, the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion include a recess that is recessed from the fixing surface.

In this case, the contact area of the valve portion of the discharge reed valve and the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion decreases, the adhesive force decreases, and the valve easily opens.

Preferably, the recess extends in a groove-shaped form along the longitudinal direction.

In this case, the contact area is decreased. Further, the adhesive force produced by the negative squeeze effect when the valve opens is decreased, and the valve easily opens.

Preferably, the recess extends in a groove-shaped form along the lateral direction.

This decreases the contact area. Further, the amount of oil supplied from the fixing surface to the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion decreases, the adhesive force decreases, and the valve easily opens.

Preferably, the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion include a crowning.

In this case, the contact area of the valve portion of the discharge reed valve and the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion decreases, the adhesive force decreases, and the valve easily opens.

Preferably, the valve portion is enlarged in a direction that differs from the longitudinal direction as compared with the intermediate portion.

In this case, enlargement of the discharge port and an increase in the pressure receiving area of the valve portion can easily be realized. Thus, the force that opens the discharge port can be further increased, and an increase in the adhesive force of lubricating oil that hinders valve opening at the intermediate portion can be avoided. As a result, over-compression can be further reduced, and power loss can be suppressed. Further, in this case, the distal region of the valve portion can further easily bend like a whip and strongly strikes the fixing surface. Thus, the advantages of the supporting portion, the main coupling portion, and the receiving portion become further prominent.

Preferably, the fixing surface includes a first groove portion, which extends around the discharge port, and a valve seat surface, which is located between the discharge port and the first groove portion. The valve portion can come into contact with the valve seat surface to close the discharge port. The first groove portion extends to a range overlapping the intermediate portion when viewing the discharge reed valve from above in a state closing the discharge port.

In this case, the valve portion seals the discharge port with the valve seat surface in a preferred manner.

Preferably, the first groove portion is an annular groove that surrounds the discharge port in a circumferential direction.

In this case, in a state in which the discharge reed valve closes the discharge port, the intermediate portion is overlapped with an arc portion in the annular groove facing the basal side in the longitudinal direction over a larger area. Thus, the area in which the fixing surface adheres to the intermediate portion is decreased by an amount corresponding to the overlapping area.

Preferably, the first groove portion has a C-shaped form and surrounds the discharge port in a circumferential direction excluding a portion at the distal side in the longitudinal direction.

In this case, the distance between the two ends of the C-shaped groove at the distal side in the longitudinal direction can be increased to easily form the receiving portion between the two ends. Thus, when the valve portion of the discharge reed valve strikes the receiving portion, the lubricating oil on the receiving portion reduces the striking force. Thus, only a small stress acts on the valve portion, and a large stress is not produced at the distal region of the valve portion. As a result, the compressor effectively prevents damage to the discharge reed valve and has a superior durability.

Preferably, the fixing surface includes a second groove portion, which is located at the basal side of the discharge port in the longitudinal direction, and a communication groove, which is located in a range overlapped with the intermediate portion and which extends along the longitudinal direction. The second groove portion extends across the intermediate portion in a lateral direction when viewing the discharge reed valve from above in a state closing the discharge port. The communication groove communicates the first groove portion and the second groove portion.

Portions in the fixing surface other than the communication groove may be a contact portion that contacts the discharge reed valve.

In this case, foreign substances are prevented from being caught by the intermediate portion in a state in which the discharge reed valve closes the discharge port. Further, when the discharge reed valve opens, a multiphase jet flow including gas and lubricating oil blows away the lubricating oil, which exists between the intermediate portion and the fixing surface and thereby removes the oil film. The jet flow is discharged outward in the lateral direction of the discharge reed valve through the communication groove and the second groove portion from the first groove portion. This blows away the lubricating oil collected in the first groove portion, the lubricating oil collected between the fixing surface and the intermediate portion and the lubricating oil collected in the second groove portion. Further, the communication groove decreases the area of contact between the fixing surface and the intermediate portion. Thus, the compressor advances the timing at which the fixing surface and the intermediate portion separate from each other. This suppresses over-compression of the gas.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a compressor according to a first embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a state in which a discharge reed valve opens a discharge port in the compressor of FIG. 1. FIG. 3 is a plan view showing a valve plate and a discharge valve plate, which includes a plurality of discharge reed valves, in the compressor of FIG. 1.

FIG. 4 is an enlarged plan view showing a state in which the discharge reed valve closes the discharge port in the compressor of FIG. 1.

FIG. 5 is an enlarged cross-sectional view taken along line Z-Z of FIG. 4 showing a state in which the discharge reed valve closes the discharge port in the compressor of FIG. 1.

FIG. 6 shows the compressor of FIG. 1, in which part (A) shows a plan view of the discharge port, and the like, part (B) shows a plan view of a discharging region, and part (C) shows a cross-sectional view of a supporting portion.

FIG. 7 is a plan view of a discharge port and the like in a compressor according to a second embodiment of the present invention.

FIG. 8 is a plan view of a discharge port and the like in a compressor according to a third embodiment of the present invention.

FIG. 9 is a plan view of a discharge port and the like in a compressor according to a fourth embodiment of the present invention.

FIG. 10 is a cross-sectional view of a supporting portion corresponding to line A-A of FIG. 6 in a compressor according to a fifth embodiment of the present invention.

FIG. 11 is a cross-sectional view of a supporting portion corresponding to line B-B of FIG. 6 in a compressor according to a sixth embodiment of the present invention.

FIG. 12 is a cross-sectional view of a supporting portion corresponding to line B-B of FIG. 6 in a compressor according to a seventh embodiment of the present invention.

FIG. 13 is a cross-sectional view of a supporting portion corresponding to line A-A of FIG. 6 in a compressor according to an eighth embodiment of the present invention.

FIG. 14 is a cross-sectional view of a supporting portion corresponding to line A-A of FIG. 6 in a compressor according to a ninth embodiment of the present invention.

FIG. 15 is a cross-sectional view of a supporting portion corresponding to line B-B of FIG. 6 in the compressor according to the ninth embodiment of the present invention.

FIG. 16 shows a compressor according to a tenth embodiment of the present invention, in which part (A) shows a plan view of a discharge port and the like, and part (B) shows a cross-sectional view of a supporting portion.

FIG. 17 is an enlarged plan view showing a state in which a discharge reed valve closes a discharge port in a compressor according to an eleventh embodiment of the present invention.

FIG. 18 is an enlarged cross-sectional view taken along line Y-Y of FIG. 17 showing a state in which the discharge reed valve closes the discharge port in the compressor of FIG. 17.

FIG. 19 is an enlarged plan view showing a state in which a discharge reed valve closes a discharge port in a compressor according to a twelfth embodiment of the present invention.

FIG. 20 is an enlarged plan view showing a state in which the discharge reed valve closes the discharge port in a compressor according to a thirteenth embodiment of the present invention.

FIG. 21 is an enlarged plan view showing a state in which a discharge reed valve closes a discharge port in a compressor according to a fourteenth embodiment of the present invention.

FIG. 22 is an enlarged plan view showing a state in which a discharge reed valve closes a discharge port in a compressor according to a fifteenth embodiment of the present invention.

FIG. 23 is a cross-sectional view illustrating the adhesive force and the like that act on the discharge reed valve.

FIG. 24 is a graph showing the relationship of the time and the bore inner pressure in a compressor.

DETAILED DESCRPTION OF THE PREFERRED EMBODIMENTS

First to fifteenth embodiments of the present invention will now be described with reference to the drawings.

First Embodiment

A compressor of a first embodiment is a variable displacement type swash plate compressor. As shown in FIG. 1, the compressor is provided with a cylinder block 1 including a plurality of cylinder bores 1a. The cylinder bores 1a are concentrically arranged at equal angular intervals and extended parallel to each other. The cylinder block 1 is held between a front housing 3, which is located in the front, and a rear housing 5, which is located in the rear, and fastened by a plurality of bolts 7 in this state. A crank chamber 9 is formed in the cylinder block 1 and the front housing 3. The rear housing 5 includes a suction chamber 5a and a discharge chamber 5b.

The front housing 3 includes a shaft hole 3a, and the cylinder block 1 includes a shaft hole 1b. A drive shaft 11 is supported in a rotatable manner by a shaft seal 9a and radial bearings 9b and 9c in the shaft holes 3a and 1b. A pulley or an electromagnetic clutch (not shown) is arranged on the drive shaft 11. A belt (not shown), which is driven by an engine of a vehicle, runs about the pulley or an electromagnetic clutch pulley.

The drive shaft 11 is press-fitted to a lug plate 13, which is arranged in the crank chamber 9. A thrust bearing 15 is arranged between the lug plate 13 and the front housing 3. The drive shaft 11 is inserted through a swash plate 17, which is arranged in the crank chamber 9, to support the swash plate 17. A link mechanism 19, which supports the swash plate 17 in a tiltable manner, couples the lug plate 13 and the swash plate 17.

Each cylinder bore 1a accommodates a piston 21, which can reciprocate in the bore 1a. A valve unit 23 is arranged between the cylinder block 1 and the rear housing 5. As shown in the enlarged view of FIG. 2, the valve unit 23 includes a suction valve plate 25, which is in contact with a rear end face of the cylinder block 1, a valve plate 27, which is in contact with the suction valve plate 25, a discharge valve plate 29, which is in contact with the valve plate 27, and a retainer plate 31, which is in contact with the discharge valve plate 29. The retainer plate 31 also functions as a gasket. The suction valve plate 25, the valve plate 27, the discharge valve plate 29, and the retainer plate 31 are stacked in this order to form the valve unit 23.

As shown in FIG. 1, front and rear shoes 33a and 33b, which form a pair, are arranged between the swash plate 17 and each piston 21. Each pair of the shoes 33a and 33b convert the wobbling movement of the swash plate 17 into a reciprocating movement of the piston 21.

The crank chamber 9 and the suction chamber 5a are connected by a bleed passage 35a, and the crank chamber 9 and the discharge chamber 5b are connected by an air supply passage (not shown). A displacement control valve (not shown) is arranged in the air supply passage. The displacement control valve is formed so that it can vary the open degree of the air supply passage in accordance with the suction pressure. A condenser is connected by a pipe to the discharge chamber 5b. The condenser is connected by a pipe to an evaporator via an expansion valve, and the evaporator is connected by a pipe to the suction chamber 5a of the compressor. The cylinder bores 1a, the pistons 21, and the valve unit 23 form compression chambers 24.

A plurality of suction ports 23a are formed in the valve plate 27, the discharge valve plate 29, and the retainer plate 31 to communicate the suction chamber 5a and the compression chambers 24. The suction valve plate 25 includes a plurality of suction reed valves 25a that open and close the suction ports 23a.

As shown in FIGS. 2 to 5, a plurality of discharge ports 23b are formed in the suction valve plate 25 and the valve plate 27 to communicate the compression chambers 24 and the discharge chamber 5b.

As shown in part (A) of FIG. 6, the discharge port 23b for each cylinder bore la is divided into two port segments 231 and 232 by a supporting portion 27t, a receiving portion 27h, a main coupling portion 27v, and a sub-coupling portion 27w, which will be described later.

As shown in FIG. 2, a plurality of discharge reed valves 29a are formed in the discharge valve plate 29 to open and close the port segments 231 and 232. The retainer plate 31 includes a retainer 31a that restricts the lift length of each discharge reed valve 29a. In the present example, as shown in FIG. 3, the discharge valve plate 29 includes a circular portion and a plurality of (six in the present embodiment) extended portions, which extend radially outward in the radial direction from the circular portion. The extended portions form the discharge reed valves 29a that open and close the discharge ports 23b.

As shown in FIGS. 4 to 6, a ring-shaped annular groove 27a, which surrounds the entire circumference of the discharge port 23b, is arranged in a fixing surface 27f, which is the surface of the valve plate 27 at the side facing the discharge chamber 5b. The annular groove 27a serves as a first groove portion of the present invention. In the fixing surface 27f, a ring-shaped region located between the discharge port 23b and the annular groove 27a forms a valve seat surface (also referred to as eyeglass portion) 27b that is flush with a portion of the fixing surface 27f located outward from the annular groove 27a. In the compressor, the suction valve plate 25 and the valve plate 27 serve as a partition wall.

As shown in FIGS. 2 to 5, each of the six discharge reed valves 29a has a basal end and a distal end and includes a fixed portion 291a, which is positioned at the basal end and fixed to the fixing surface 27f of the valve plate 27, an intermediate portion 292a, which extends toward the distal end along the longitudinal direction of the discharge reed valve 29a from the fixed portion 291a and can be lifted, and a valve portion 293a, which extends toward the distal end along the longitudinal direction from the intermediate portion 292a to open and close the discharge port 23b. In the present embodiment, the longitudinal direction is a direction that is parallel to the fixing surface 27f and that extends in the radial direction of the drive shaft 11. In FIG. 4, in particular, the longitudinal direction from the basal end toward the distal end of each discharge reed valve 29a is indicated by reference character D1, and the longitudinal direction from the distal end toward the basal end of each discharge reed valve 29a is indicated by reference character D2.

As shown in FIG. 4, when viewing the intermediate portion 292a and the valve portion 293a from above, the intermediate portion 292a has a rectangular shape in which the long sides extend toward the distal side in the longitudinal direction D1. The valve portion 293a is a circle concentric with the annular groove 27a having the short side of the intermediate portion 292a as the diameter. A diameter of the valve portion 293a in a direction orthogonal to the longitudinal direction D1 is greater than the diameter of the valve seat surface 27b in the longitudinal direction D1.

As shown in FIGS. 4 and 6, the valve plate 27 includes the supporting portion 27t, which receives the central region of the valve portion 293a, the receiving portion 27h, which receives the distal region of the valve portion 293a, the main coupling portion 27v, which couples the supporting portion 27t and the receiving portion 27h, and the sub-coupling portion 27w, which extends from the supporting portion 27t. The valve portion 293a is circular, and the central region of the valve portion 293a is thus a fixed range including the center of the valve portion 293a. The distal region of the valve portion 293a is a fixed range located at the distal side of the central region. As shown in part (B) of FIG. 6, the valve plate 27 includes a discharging region A, through which the discharge port 23b extends. The discharging region A includes a semicircular distal discharging region A1 located at the distal side in the longitudinal direction D1 and a semicircular basal discharging region A2 located at the basal side in the longitudinal direction D1. As shown in part (A) of FIG. 6, the supporting portion 27t is a fixed range including the center O of the discharging region A. The supporting portion 27t is arranged to receive the central region of the valve portion 293a, and the discharge port 23b is located at the left and right of the distal side and the left and right of the basal side in the longitudinal direction D1 as viewed from the supporting portion 27t. The main coupling portion 27v extends from the supporting portion 27t to divide the distal discharging region A1 into two. The sub-coupling portion 27w divides the basal discharging region A2 into two. The discharge port 23b extends through the valve plate 27 so as to leave the supporting portion 27t, the receiving portion 27h, the main coupling portion 27v, and the sub-coupling portion 27w in the valve plate 27. The supporting portion 27t, the receiving portion 27h, the main coupling portion 27v, and the sub-coupling portion 27w are arranged in the valve plate 27 and thereby divide the discharge port 23b into two port segments 231 and 232.

The sub-coupling portion 27w, the supporting portion 27t, the main coupling portion 27v, and the receiving portion 27h are in an I-shaped form extending toward the distal side in the longitudinal direction D1. As shown in part (C) of FIG. 6, the supporting portion 27t, the receiving portion 27h, the main coupling portion 27v, and the sub-coupling portion 27w are flush with the fixing surface 27f. The supporting portion 27t, the receiving portion 27h, the main coupling portion 27v, and the sub-coupling portion 27w are located between the port segments 231 and 232. The port segments 231 and 232, which are shaped in such a manner, are formed, for example, by punching and pressing the valve plate 27.

As shown in part (A) of FIG. 6, the supporting portion 27t, the main coupling portion 27v, and the sub-coupling portion 27w have the same width in a direction orthogonal to the longitudinal direction D1. However, the receiving portion 27h has a larger width than the supporting portion 27t, the main coupling portion 27v, and the sub-coupling portion 27w. The port segments 231 and 232 have corners that are not pointed but slightly rounded due to accuracy limitations of the punching and pressing or the like.

As shown in FIGS. 2 to 5, a long groove 27c is arranged in the fixing surface 27f at the basal side of the discharge port 23b in the longitudinal direction D1 extending across the intermediate portion 292a in its lateral direction. The long groove 27c serves as a second groove portion of the present invention. As shown in FIG. 4, when viewing the long groove 27c from above, the shape of the long groove 27c is an oblong ellipse that is orthogonal to the longitudinal direction D1. The long groove 27c is deeper than the annular groove 27a.

In the above compressor, when the drive shaft 11 is driven and rotated, the lug plate 13 and the swash plate 17 are synchronously rotated with the drive shaft 11, and the pistons 21 are reciprocated in the cylinder bores 1a with a stroke corresponding to the tilt angle of the swash plate 17. Thus, refrigerant gas is drawn from the suction chamber 5a into each compression chamber 24 and compressed. Then, the refrigerant gas is discharged to the discharge chamber 5b. The refrigerant gas that undergoes compression in the compressor contains lubricating oil in the form of a mist. The lubricating oil collects on sliding and moving parts such as the pistons 21, the shoes 33a and 33b, the swash plate 17, and the like to suppress wear. The lubricating oil is also collected in the annular grooves 27a and the long grooves 27c.

In this state, as shown in FIG. 2, the discharge reed valve 29a is elastically deformed at the intermediate portion 292a due to the difference between the pressure in the discharge chamber 5b and the pressure in the compression chamber 24. This opens the discharge port 23b at the valve portion 293a. As shown in FIG. 5, the valve portion 293a does not open the discharge port 23b until the pressure difference prevails over the adhesive force of the intermediate portion 292a.

In this compressor, when the force of inertia or pressure difference acts to greatly bend the central region of the valve portion 293a into the discharge port 23b at the moment the discharge reed valve 29a closes the discharge port 23b, the supporting portion 27t supports the central region of the valve portion 293a. The sub-coupling portion 27w, the supporting portion 27t, the main coupling portion 27v, and the receiving portion 27h are in an I-shaped form extending along the longitudinal direction D1. This increases the strength of the supporting portion 27t, and the valve portion 293a that strikes the fixing surface 27f while bending like a whip toward the distal side along the longitudinal direction D1 can easily be supported sequentially from the basal side toward the distal side in the longitudinal direction D1. This prevents fatigue failure at the valve portion 293a.

In this compressor, in particular, when the valve portion 293a of the discharge reed valve 29a strikes the receiving portion 27h, the lubricating oil on the receiving portion 27h reduces the striking force due to the squeeze film effect so that only a small stress acts on the valve portion 293a, and a large stress is not produced at the distal end of the valve portion 293a. This further prevents fatigue failure at the discharge reed valve 29a, and the compressor can exhibit high durability.

In the compressor, due to the operations described above, the pressure receiving area of the valve portion 293a is increased, the force that opens the discharge port 23b is increased, and the adhesive force of the lubricating oil inhibiting valve opening is reduced. Thus, over-compression can be decreased and power loss can be suppressed.

Accordingly, the compressor can further reduce power loss and exhibit higher durability.

In the compressor, discharging pulsation can be reduced by suppressing the opening delay of the discharge reed valve 29a. This improves the quietness of the compressor. Further, in the compressor, the peak pressure in the compression chamber 24 can be lowered. Thus, the maximum compression load can be reduced, and the reliability can be increased for the thrust bearing 15, the surfaces of contact of the shoes 33a and 33b and the pistons 21, the sliding surfaces of the shoes 33a and 33b and the swash plate 17, and the like.

In the compressor, the annular groove 27a is arranged in the fixing surface 27f, as shown in FIG. 4. Thus, the intermediate portion 292a and an arc portion 27g (shown in FIG. 4) of the annular groove 27a are overlapped over a wide range in a state in which the discharge reed valve 29a closes the discharge port 23b. The overlapping area reduces the area of contact between the fixing surface 27f and the intermediate portion 292a. This shortens opening delays of the discharge reed valve 29a.

Further, in the compressor, the long groove 27c is arranged in the fixing surface 27f. Thus, foreign substances are prevented from being caught by the intermediate portion 292a in a state in which the discharge reed valve 29a closes the discharge port 23b.

Second Embodiment

As shown in FIG. 7, in a compressor of a second embodiment, four triangular port segments 231 to 234 having a center angle of approximately 90 degrees are combined to form the discharge port 23b.

The supporting portion 27d, the main coupling portion 27v, the receiving portion 27h, and first to third sub-coupling portions 27w1 to 27w3 are formed in the valve plate 27. The first sub-coupling portion 27w1 extends along the longitudinal direction D1. The second sub-coupling portion 27w2 extends at an angle of 90° in the clockwise direction from the main coupling portion 27v. The third sub-coupling portion 27w3 extends at an angle of 90° in the counterclockwise direction from the main coupling portion 27v. The first to third sub-coupling portions 27w1 to 27w3 are arranged between the port segments 231 to 234. The other parts are the same as the compressor of the first embodiment.

This compressor also has the same advantages as the compressor of the first embodiment.

Third Embodiment

As shown in FIG. 8, in a compressor of a third embodiment, three triangular port segments 231 to 233 having a center angle of approximately 120 degrees are combined to form the discharge port 23b.

A supporting portion 27e, the main coupling portion 27v, the receiving portion 27h, and the first and second sub-coupling portions 27w1, 27w2 are formed in the valve plate 27. The first sub-coupling portion 27w1 extends at an angle of 120° in the clockwise direction from the main coupling portion 27v. The second sub-coupling portion 27w2 extends at an angle of 120° in the counterclockwise direction from the main coupling portion 27v. The supporting portion 27e, the main coupling portion 27v, the receiving portion 27h, and the first and second sub-coupling portions 27w1 and 27w2 are arranged between the port segments 231 to 233. The other parts are the same as the compressor of the first embodiment.

This compressor also has the same advantages as the compressor of the first embodiment.

Fourth Embodiment

As shown in FIG. 9, a compressor of a fourth embodiment includes half-moon shaped port segments 231 and 232. The sub-coupling portion 27w, a supporting portion 27i, the main coupling portion 27v, and a receiving portion 27j have widths that increase toward the distal side in the longitudinal direction D1. The other parts are the same as the compressor of the first embodiment.

This compressor also has the same advantages as the compressor of the first embodiment.

The present invention drastically suppresses large bending of the central region of the valve portion 293a into the discharge port 23b. Thus, the valve portion 293a does not have to entirely contact the supporting portion, the receiving portion, the main coupling portion, and the sub-coupling portion. This allows the forms of fifth to tenth embodiments described below to be adopted.

Fifth Embodiment

As shown in FIG. 10, in a compressor of a fifth embodiment, a recess 27k is formed in a surface of the supporting portion 27t or the like. The recess 27k is formed to be groove-shaped at the two lateral ends of the supporting portion 27t or the like. The other parts are the same as the compressor of the first embodiment.

In this compressor, the contact area of the valve portion 293a and the supporting portion 27t and the like is small. This reduces the adhesive force and facilitates valve opening. In this structure, the supporting portion 27t or the like has a width that suppresses the contact area, and further, the adhesive force while maintaining the strength. The other advantages are the same as the first embodiment.

Sixth Embodiment

As shown in FIG. 11, in a compressor of a sixth embodiment, a recess 28a is formed in a surface of the supporting portion 27t or the like. The recess 28a is formed to groove-shaped along the longitudinal direction of the supporting portion 27t or the like. The other parts are the same as the compressor of the first embodiment.

In this compressor, the contact area is reduced and the adhesive force produced by the negative squeeze effect is reduced during valve opening. This facilitates valve opening. The other advantages are the same as the first embodiment.

Seventh Embodiment

As shown in FIG. 12, in a compressor of a seventh embodiment, narrow groove-like recesses 27m are formed in the two longitudinal ends of the supporting portion 27t or the like. The recesses 27m extends along the lateral direction of the supporting portion 27t or the like. The other parts are the same as the compressor of the first embodiment.

In this compressor, the movement of lubricating oil is blocked between the valve seat surface 27b and the supporting portion 27t or the like by the recesses 27m. This stops the supply of lubricating oil from the valve seat surface 27b to the supporting portion 27t or the like, reduces the adhesive force that acts between the supporting portion 27t or the like and the valve portion 293a, and facilitates valve opening. The other advantages are the same as the first embodiment.

Eighth Embodiment

As shown in FIG. 13, in a compressor of an eighth embodiment, three narrow groove-like recesses 27n are located between recesses 27s, which are arranged at the two ends, in the supporting portion 27t or the like. The other parts are the same as the compressor of the sixth embodiment.

In this compressor, the contact area of the supporting portion 27t or the like and the valve portion 293a is reduced and the adhesive force is reduced. This facilitates valve opening. The other advantages are the same as the first embodiment.

Ninth Embodiment

As shown in FIG. 14 or 15, in a compressor of a ninth embodiment, a crowning 27p is formed on the supporting portion 27t or the like. The other parts are the same as the compressor of the first embodiment.

In this compressor, the contact area of the valve portion 293a and the supporting portion 27t or the like is reduced, the adhesive force is reduced, and valve opening is facilitated. The other advantages are the same as the first embodiment.

Tenth Embodiment

As shown in FIG. 16, in a compressor of a tenth embodiment, a plurality of recesses 27q are formed by coining and then grinding the supporting portion 27t or the like. The other parts are the same as the compressor of the first embodiment. This compressor also has the same advantages as the compressor of the sixth embodiment.

Eleventh Embodiment

As shown in FIGS. 17 and 18, in a compressor of an eleventh embodiment, a communication groove 27r, which extends toward the distal side in the longitudinal direction D1, is formed in the fixing surface 27f to communicate the annular groove 27a and the long groove 27c. Portions of the fixing surface 27f other than the communication groove 27r form a contact portion 27s that comes into contact with the discharge reed valve 29a. The contact portion 27s is located at the two laterals sides of the communication groove 27r in the fixing surface 27f. Further, the contact portion 27s is overlapped with the intermediate portion 292a when the discharge reed valve 29a is in state of closing the discharge port 23b as viewed from above. In the present example, the width of the communication groove 27r is about 50% to 75% the width of the intermediate portion 292a. This ensures that the contact portion 27s supports the intermediate portion 292a.

In the compressor, when the discharge reed valve 29a opens, some of a multiphase jet flow including the refrigerant gas and the lubricating oil blows away the lubricating oil, which exists between the intermediate portion 292a and the fixing surface 27f, and thereby the multiphase jet flow removes the oil film. The jet flow is discharged outward in the lateral direction of the discharge reed valve 29a through the communication groove 27r and the long groove 27c from the annular groove 27a. This blows away the lubricating oil collected in the annular groove 27a, the lubricating oil accumulated between the fixing surface 27f and the intermediate portion 292a, and the lubricating oil collected in the long groove 27c. The communication groove 27r decreases the area of contact between the fixing surface 27f and the intermediate portion 292a. Thus, the compressor further advances the timing at which the fixing surface 27f and the intermediate portion 292a separate from each other. This suppresses over-compression of the refrigerant gas. The other advantages are the same as the first embodiment.

Twelfth Embodiment

As shown in FIG. 19, in a compressor of a twelfth embodiment, the valve portion 293a has a circular shape having a diameter that is greater than or equal to the short sides of the intermediate portion 292a. In other words, the valve portion 293a is enlarged with respect to the intermediate portion 292a in a direction differing from the longitudinal direction D1. The other parts are the same as the first embodiment.

In this case, enlargement of the discharge port 23b and an increase in the pressure receiving area of the valve portion 293a can be easily realized. This further increases the force that opens the discharge port 23b, and the adhesive force of the lubricating oil that inhibits the valve opening in the intermediate portion 292a is prevented from being increased. As a result, over-compression can be further reduced, and power loss can be suppressed in an ensured manner. In this case, the distal end toward the distal side in the longitudinal direction D1 of the valve portion 293a is more easily bent like a whip and thus strongly strikes the fixing surface 27f. Thus, the advantages of the supporting portion 27t or the like become more prominent. The other advantages are the same as the first embodiment.

Thirteenth Embodiment

As shown in FIG. 20, in a compressor of a thirteenth embodiment, the supporting portion 27i or the like of the fourth embodiment is used in lieu of the supporting portion 27t or the like of the first embodiment, and a C-shaped groove 27y is used in lieu of the annular groove 27a of the first embodiment. The C-shaped groove 27y also serves as the first groove portion of the present invention. The C-shaped groove 27y, which has an arcuate shape concentric with the center O, is formed in the fixing surface 27f and surrounds the discharge port 23b in the circumferential direction excluding the distal side in the longitudinal direction D1. A region of the fixing surface 27f sandwiched by the opposing ends of the C-shaped groove 27y defines a receiving portion 27j and a receiving portion 27z. The other parts are the same as the first embodiment.

In this case, the distance between the opposing ends of the C-shaped groove 27y can be increased to facilitate formation of the receiving portions 27j and 27z that are enlarged in the lateral direction of the supporting portion 27i as compared with other parts of the supporting portion 27i (parts of the supporting portion 27i other than the receiving portions 27j and 27z). Thus, when the valve portion 293a strikes the receiving portions 27j and 27z, the lubricating oil on the large receiving portions 27j and 27z ensure that the striking force is decreased. Thus, only a small stress acts on the valve portion 293a, and a large stress is not produced at the distal end of the valve portion 293a. As a result, this compressor also effectively prevents damage to the discharge reed valve 29a and obtains superior durability. The other advantages are the same as the first embodiment.

Fourteenth Embodiment

As shown in FIG. 21, in a compressor of a fourteenth embodiment, the supporting portion 27i or the like of the fourth embodiment is used in lieu of the supporting portion 27t or the like of the first embodiment, and two first groove portions 27x are used in lieu of the annular groove 27a of the first embodiment. The first groove portions 27x, which are arc-shaped and concentric with the center O, are formed in the fixing surface 27f and surround the discharge port 23b from the left and the right excluding the distal side and the basal side in the longitudinal direction D1. A region sandwiched by the opposing ends on the distal side in the longitudinal direction D1 in the first groove portions 27x define a receiving portion 27j and a receiving portion 27z in the fixing surface 27f. A region sandwiched by the opposing ends at the basal side in the longitudinal direction D1 in the first groove portions 27x defines a basal side receiving portion 274 in the fixing surface 27f. The other parts are the same as the first embodiment.

In this case, the distance between the opposing ends of the first groove portions 27x at the distal side in the longitudinal direction D1 is increased to facilitate formation of the receiving portions 27j and 27z that are larger than other portions. Thus, in the same manner as the compressor of the thirteenth embodiment, a large stress is not produced at the distal end of the valve portion 293a. Further, in the compressor, when the intermediate portion 292a of the discharge reed valve 29a strikes the basal side receiving portion 274, only a small stress acts on the intermediate portion 292a due to the large basal side receiving portion 274. As a result, this compressor also effectively prevents damages to the discharge reed valve 29a and obtains superior durability. The other advantages are the same as the first embodiment.

Fifteenth Embodiment

As shown in FIG. 22, in a compressor of a fifteenth embodiment, only a supporting portion 27u, the main coupling portion 27v, and the receiving portion 27h are arranged in the valve plate 27, and a U-shaped discharge port 23b is used. Thus, the supporting portion 27u can receive the central region of the valve portion 293a in the same manner as the supporting portion 27t of the first embodiment. The other parts are the same as the first embodiment.

In this case as well, the same advantages as the first embodiment are obtained.

The present invention has been described with the first to fifteenth embodiments. However, the present invention is not limited to the first to fifteenth embodiments and may be modified within the scope of the invention.

For instance, the supporting portion or the like may be formed in the valve plate 27 or by a discrete member such as a damping steel plate or the like.

The long groove 27c is deeper than the annular groove 27a in the first embodiment, and the annular groove 27a, the long groove 27c, and the communication groove 27r are formed with the same depth in the eleventh embodiment. However, the depths are not limited in such a manner.

The recesses 27k, 27a, 27m, 27s, and 27q and the crowning 27p described in the fifth to tenth embodiments may be arranged in only the supporting portion 27t or may be arranged extending across the supporting portion 27t, the main coupling portion 27v, and the sub-coupling portions 27w, and 27w1 to 27w3.

INDUSTRIAL APPLICABILITY

The present invention may be applied to a vehicle air conditioning system.

Claims

1. A compressor comprising:

a discharge chamber;

a compression chamber;

a partition wall arranged between the discharge chamber and the compression chamber and including a fixing surface that faces the discharge chamber, wherein the partition wall includes a discharge port that can communicate the discharge chamber and the compression chamber; and

a discharge reed valve having a length extending along a longitudinal direction, a distal end, and a basal end, wherein the discharge reed valve includes a fixed portion located at the basal end and fixed to the fixing surface, an intermediate portion extending from the fixed portion toward the distal end and being liftable relative to the fixing surface, and a valve portion further extending from the intermediate portion toward the distal end and being capable of opening and closing the discharge port, wherein

the partition wall includes a supporting portion that supports a central region of the valve portion, a receiving portion that receives a distal region of the valve portion, and a main coupling portion that extends from the supporting portion to couple the supporting portion and the receiving portion in order to divide into two a distal discharging region of the discharge port located at a distal side of the supporting portion in the longitudinal direction,

the discharge port extends through the partition wall so as to leave the supporting portion, the receiving portion, and the main coupling portion in the partition wall, and

the receiving portion has a larger width than the supporting portion in a direction orthogonal to the longitudinal direction.

2. The compressor according to claim 1, wherein

the partition wall includes a sub-coupling portion extending from the supporting portion to divide at least into two a basal discharging region of the discharge port located at a basal side of the supporting portion in the longitudinal direction, and

the discharge port extends through the partition wall so as to leave the supporting portion, the receiving portion, the main coupling portion, and the sub-coupling portion in the partition wall.

3. The compressor according to claim 2, wherein

the sub-coupling portion extends along the longitudinal direction; and

the discharge port is divided into two port segments by the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion.

4. The compressor according to claim 3, wherein the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion have widths that increase toward the distal side in the longitudinal direction.

5. The compressor according to claim 2, wherein

the sub-coupling portion includes a first sub-coupling portion, which extends along the longitudinal direction, a second sub-coupling portion, which extends at an angle of 90° in a clockwise direction from the main coupling portion, and a third sub-coupling portion, which extends along at an angle of 90° in a counterclockwise direction from the main coupling portion, and

the discharge port is divided into four port segments by the first sub-coupling portion, the second sub-coupling portion, the third sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion.

6. The compressor according to claim 2, wherein

the sub-coupling portion includes a first sub-coupling portion, which extends at an angle of 120° in a clockwise direction from the main coupling portion, and a second sub-coupling portion, which extends at an angle of 120° in a counterclockwise direction from the main coupling portion, and

the discharge port is divided into three port segments by the first sub-coupling portion, the second sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion.

7. The compressor according to claim 2, wherein the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion are flush with the fixing surface.

8. The compressor according to claim 2, wherein the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion include a recess that is recessed from the fixing surface.

9. The compressor according to claim 8, wherein the recess extends in a groove-shaped form along the longitudinal direction.

10. The compressor according to claim 8, wherein the recess extends in a groove-shaped form along the lateral direction.

11. The compressor according to claim 2, wherein the sub-coupling portion, the supporting portion, the main coupling portion, and the receiving portion include a crowning.

12. The compressor according to claim 1, wherein the valve portion is enlarged in a direction that differs from the longitudinal direction as compared with the intermediate portion.

13. The compressor according to claim 1, wherein

the fixing surface includes a first groove portion, which extends around the discharge port, and a valve seat surface, which is located between the discharge port and the first groove portion,

the valve portion can come into contact with the valve seat surface to close the discharge port, and

the first groove portion extends to a range overlapping the intermediate portion when viewing the discharge reed valve from above in a state closing the discharge port.

14. The compressor according to claim 13, wherein the first groove portion is an annular groove that surrounds the discharge port in a circumferential direction.

15. The compressor according to claim 13, wherein the first groove portion has a C-shaped form and surrounds the discharge port in a circumferential direction excluding a portion at the distal side in the longitudinal direction.

16. The compressor according to claim 1, wherein

the fixing surface includes a second groove portion, which is located at the basal side of the discharge port in the longitudinal direction, and a communication groove, which is located in a range overlapped with the intermediate portion and which extends along the longitudinal direction,

the second groove portion extends across the intermediate portion in a lateral direction when viewing the discharge reed valve from above in a state closing the discharge port, and

the communication groove communicates the first groove portion and the second groove portion.