Electric compressor

Abstract

The present invention provides an electric compressor that can realize high durability and high efficiency by means of a low-cost construction, and is advantageous in providing a construction for using a carbon dioxide refrigerant. In the electric compressor in accordance with the present invention, the rotational motion of an inclined plate 23 having a predetermined fixed angle of inclination is converted to swinging motion of a swing plate 24 that swings while the rotation thereof is regulated, and pistons 21 are driven by the swinging motion of the swing plate 24. Therefore, a construction having no sliding part due to the rotation of the inclined plate 23 can be provided, so that the durability can be improved.

Description

TECHNICAL FIELD

The present invention relates to an electric compressor used for a vehicular air conditioner using a carbon dioxide refrigerant.

BACKGROUND ART

Generally, as the electric compressor of this type, what is called a scroll compressor, in which a refrigerant is compressed by a predetermined revolving motion of one of a pair of spiral members that faces the other spiral member, as described in Japanese Patent Publication 2000-291557, is known. Besides, what is called a rolling piston type compressor, in which a refrigerant is compressed by revolving a piston having an outside diameter smaller than the inside diameter of a cylinder along the inner peripheral surface of the cylinder, as described in Japanese Patent Publication 2000-130870, is also known.

However, in the case where a carbon dioxide refrigerant is used, the above-described rotary compressors have a problem in that the sealing ability of a compression chamber cannot be maintained sufficiently, because the carbon dioxide refrigerant provides a pressure higher than that of the conventional CFC gas or HFC gas.

To solve this problem, as a piston type compressor capable of maintaining the sealing ability of compression chamber even under a high pressure condition, a compressor, in which the rotation of a motor is converted to reciprocating motion of a piston by an inclined plate, as described in Japanese Patent Publication 2001-304127, is known. However, in order to obtain a high pressure, the inclined plate must be rotated at a high speed. In a construction using the inclined plate, the inclined plate rotates while being in contact with a shoe on the piston side, so that there arise problems in terms of durability under a high load state of a sliding portion between the shoe and the inclined plate and under severe lubricating conditions. Therefore, when a refrigeration circuit using the carbon dioxide refrigerant is practically used, in order to enhance the durability of compressor, a strong and expensive part must be used for, for example, a principal part, which presents a problem of increased cost.

The present invention has been made in view of the above-described problems, and accordingly an object thereof is to provide an electric compressor which can realize high durability and high efficiency by means of a low-cost construction, and is advantageous in providing a construction for using a carbon dioxide refrigerant.

DISCLOSURE OF THE INVENTION

The present invention provides an electric compressor including a plurality of cylinders arranged in the circumferential direction on one end side of a compressor body; a plurality of pistons reciprocating in the cylinders; a drive shaft for driving the pistons; and a motor for rotating the drive shaft, so that a refrigerant is sucked and discharged by reciprocating the pistons in the axial direction of the drive shaft, characterized in that the electric compressor further includes an inclined member which has an inclined surface, making a predetermined fixed angle of inclination with respect to the drive shaft, at one end thereof and rotates integrally with the drive shaft; and a swing member to which the pistons are connected via a connecting member having a universal joint at a predetermined position in the circumferential direction and which reciprocates the pistons by swinging along the inclined surface of the rotating inclined member while the rotation thereof is regulated, and a carbon dioxide refrigerant is used as the refrigerant.

Thereupon, when the drive shaft is rotated by the motor, the inclined member rotates, and the swing member swings along the inclined surface of the inclined member while the rotation thereof is regulated. Thereby, connecting members of the pistons connected to the swing member are displaced successively in the axial direction of the drive shaft, and hence the pistons reciprocate in the cylinders. Therefore, there is provided a construction that has no sliding part due to the rotation of the inclined member and has high durability even under severe service conditions such as high load and poor lubricating condition using the carbon dioxide refrigerant.

Also, according to the present invention, in the above-described configuration, a refrigerant suction chamber for accommodating the refrigerant sucked into the cylinders and a refrigerant discharge chamber into which the refrigerant is discharged from the cylinders are provided on one end side of the compressor body, and the refrigerant suction chamber is formed in a central portion on one end side of the compressor body, and the refrigerant discharge chamber is formed in a ring form around the refrigerant suction chamber.

Thereupon, since the refrigerant discharge chamber is formed in a ring form around the refrigerant suction chamber, the surface area of the refrigerant discharge chamber is decreased as compared with the case where the refrigerant discharge chamber is formed in the central portion on one end side of the compressor body, and thus a force caused by the sum of pressures of refrigerant applied to the wall surface of the compressor body is reduced.

Also, according to the present invention, in the above-described configuration, a refrigerant suction port is provided on the other end side of the compressor body so that a refrigerant sucked through the refrigerant suction port flows in the compressor body and is sucked into the cylinders.

Thereupon, the refrigerant sucked to the other end side of the compressor body flows through movable parts and sliding parts in the compressor boy, and then is sucked into the cylinders, so that the movable parts and sliding parts are lubricated by the refrigerant with which a lubricating oil is mixed. Also, by the buffering action at the time when the refrigerant flows through the movable parts and sliding parts, the pulsation of refrigerant on the suction side is damped.

Also, according to the present invention, in the above-described configuration, the inclined member is provided at one end of the drive shaft, and the motor is arranged on the other end side of the drive shaft; and the drive shaft is supported by only at least one bearing arranged on the other end side of the inclined member.

Thereupon, since the drive shaft is supported by only the bearing arranged on the other end side of the inclined member, a part for supporting the drive shaft is not needed on one end side of the drive shaft, that is, on the inclined surface side of the inclined plate.

Also, according to the present invention, in the above-described configuration, a first housing arranged on the side of the pistons, swing member, and inclined member and a second housing arranged on the side of the motor are provided, and an intermediate plate having a bearing for the drive shaft is provided between the housings.

Thereupon, the thrust force of the inclined member and the radial force of the drive shaft can be supported with a high strength by the intermediate plate provided between the housings.

Also, according to the present invention, in the above-described configuration, the inclined member is provided so that one end side of the drive shaft penetrates the inclined member, and the motor is arranged on the other end side of the drive shaft; the other end of the drive shaft is supported by a bearing; and supporting means which rotatably supports one end of the drive shaft and swingingly supports the swing member is provided on one end side of the drive shaft.

Thereupon, one end side of the drive shaft is rotatably supported by the supporting means, and the swing member is swingingly supported by the supporting means, so that a special-purpose bearing for supporting one end side of the drive shaft need not be provided.

Also, according to the present invention, in the above-described configuration, the supporting means is formed by a spherical body to which one end of the drive shaft is connected and which engages slidably with a central portion of the swing member and a spherical body supporting member for slidably supporting the spherical body.

Thereupon, the spherical body of drive shaft is rotatably supported by the spherical body supporting member, and the swing member is swingingly supported by the spherical body, so that the rotating motion of the drive shaft and the swinging motion of the swing member are achieved by the common spherical body.

BRIEFLY DESCRIBE OF THE DRAWINGS

FIG. 1 is a side sectional view of an electric compressor showing one embodiment of the present invention;

FIG. 2 is a sectional view taken along the line A-A of FIG. 1;

FIG. 3 is a sectional view taken along the line B-B of FIG. 1; and

FIG. 4 is a side sectional view of an electric compressor in accordance with another embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

FIGS. 1 to 3 show one embodiment of the present invention.

This electric compressor includes a compressor body 10 for sucking and discharging a refrigerant, a compression section 20 for compressing the refrigerant sucked into the compressor body 10, and a motor 30 for driving the compression section 20.

The compressor body 10, which is formed into a cylindrical shape, includes a first housing 11 formed on the position of the compression section 20 side, a second housing 12 formed on the position of the motor 30 side, a cylinder head 13 arranged on one end side of the first housing 11, a valve plate 14 arranged between the first housing 11 and the cylinder head 13, and an intermediate plate 15 arranged between the housings 11 and 12.

The first housing 11 has a plurality of cylinders 11a, which are arranged at equal intervals in the circumferential direction, on one end side thereof, and one end of each of the cylinders 11a is open to one end face side of the first housing 11. The first housing 11 has a plurality of refrigerant passages 11b that penetrates one end side of the first housing 11. The refrigerant passages 11b are arranged between the cylinders 11a. Also, the first housing 11 is formed so that the other end side thereof is open, and is connected to one end of the second housing 12 via the intermediate plate 15 by bolts 11c.

The second housing 12 is formed so that one end side thereof is open, and is provided with a refrigerant suction port 12a on the other end side thereof.

The cylinder head 13 is attached to one end of the first housing 11 via the valve plate 14, and is provided with a refrigerant suction chamber 13a, which is open to the valve plate 14 side, in the central portion thereof. Around the refrigerant suction chamber 13a, there is provided a ring-shaped refrigerant discharge chamber 13b that is open to the valve plate 14 side. The refrigerant discharge chamber 13b communicates with a refrigerant discharge port 13c provided at the side of the cylinder head 13.

The valve plate 14 is provided with a plurality of refrigerant suction ports 13a and discharge ports 14b, each communicating with the cylinders 11a. The refrigerant suction ports 13a communicate with the refrigerant suction chamber 13a in the cylinder head 13, and the refrigerant discharge ports 14b communicate with the refrigerant discharge chamber 13b. The valve plate 14 is fitted with plate-shaped suction valves 14c and discharge valves 14d for opening and closing the refrigerant suction ports 13a and discharge ports 14b, respectively, so that each of the refrigerant suction ports 13a and discharge ports 14b is opened and closed by the elastic deformation of each of the valves 14c and 14d. Also, in the center of the valve plate 14 is provided a through hole 14e, and around the through hole 14e are provided a plurality of communication holes 14f each communicating with the refrigerant passage 11b in the first housing 11.

The intermediate plate 15 is formed so as to have a size such as to cover the openings of the housings 11 and 12, and the peripheral end portion thereof is attached to the end faces of the housings 11 and 12 so that the intermediate plate 15 is held between the housings 11 and 12. The intermediate plate 15 has a plurality of communication holes 15a communicating with the housings 11 and 12, and also is provided with a bearing 15b consisting of a roller bearing in the center thereof.

The compression section 20 includes a plurality of pistons 21 provided in the cylinders 11a, a drive shaft 22 rotated by the motor 30, an inclined plate 23 rotated by the drive shaft 22, and a swing plate 24 swung by the rotation of the inclined plate 23. The pistons 21 are connected to the swing plate 24 via a plurality of piston rods 25 each constituting a connecting member.

In the peripheral surface on one end side of each of the pistons 21 is installed a piston ring 21a, and on the other side thereof is provided a spherically-shaped connecting portion 21b connecting with the piston rod 25.

The drive shaft 22 extends in the first and second housings 11 and 12, and one end side thereof is arranged in the first housing 11. The drive shaft 22 is rotatably supported at two places in the axial direction by a bearing 22a consisting of a roller bearing, which is provided on the other end side of the second housing 12, and the bearing 15b of the intermediate plate 15.

The inclined plate 23 is attached to one end of the drive shaft 22 so as to be rotated integrally with the drive shaft 22. At one end of the inclined plate 23, there is formed an inclined surface 23a making a predetermined angle of inclination with respect to the axis of rotation of the drive shaft 22, and the angle of inclination is fixed to 15 degrees, for example. Also, between the other end surface of the inclined plate 23 and the intermediate plate 15 is provided a roller bearing 23b.

The swing plate 24 is arranged on the inclined surface 23a side of the inclined plate 23, and is inclined along the inclined surface 23a. In this case, the swing plate 24 is formed so that the rotation of the inclined plate 23 with respect to the swing plate 24 is allowed by a roller bearing 24a provided between the swing plate 24 and the inclined surface 23a. Also, on one end side of the swing plate 24 is provided a spherical body 26 swingingly supporting the swing plate 24. Specifically, in the center of the swing plate 24 is attached an engagement member 27 engaging with the spherical body 26, and the engagement member 27 swingingly receives the spherical body 26 in a substantially semispherical spherical portion. Also, the first housing 11 is provided with a spherical body supporting member 28 engaging with the spherical body 26, and the spherical body supporting member 28 swingingly receives the spherical body 26 in a substantially semispherical spherical portion. That is to say, the swing plate 24 is supported on the supporting member 28 via the spherical body 26, and swings while rotating along the spherical surface of the spherical body 26. Also, the spherical body supporting member 28 is provided with a communication hole 28b causing the spherical portion that supports the spherical body 26 to communicate with the through hole 14e in the valve plate 14. The engagement member 27 of the swing plate 24 and the spherical body supporting member 28 are provided with gears 27a and 28a, respectively, that mesh with each other, so that the meshing of the gears 27a and 28a regulates the rotation of the swing plate 24. Further, the swing plate 24 is provided with a plurality of spherically-shaped connecting portions 24d that each connect with the piston rod 25. The connecting portions 24d are arranged at equal intervals in the circumferential direction.

The piston rod 25 has spherically-shaped connecting portions 25a at both ends. The connecting portion 25a on one end side is connected swingingly to the connecting portion 21b in the piston 21, and the connecting portion 25a on the other end side is connected swingingly to the connecting portion 24d in the swing plate 24. In other words, the connecting portions 21b, 24d and 25a form a universal joint.

The motor 30 includes a stator 31 fixed on the inner peripheral surface of the second housing 12, a rotor 32 consisting of a permanent magnet rotating in the stator 31, and a coil 33 for excitation, which is wound at several places in the peripheral direction of the stator 31. The rotor 32 is attached to the other end side of the drive shaft 22 so as to be rotatable integrally. That is to say, the motor 30 consists of a three-phase alternate current brushless motor.

In the electric compressor constructed as described above, when the drive shaft 22 is rotated by the motor 30, the inclined plate 23 rotates, and the swing plate 24 swings along the inclined surface 23a of the inclined plate 23. At this time, the swing plate 24 swings around the spherical body 26 while the rotation thereof is regulated by the gears 27a and 28a. Thereby, the piston rods 25 connected to the swing plate 24 are displaced successively in the axial direction of the drive shaft 22, and hence the pistons 21 reciprocate in the cylinders 11a with a predetermined phase difference. Also, by the reciprocating motion of the pistons 21, a refrigerant in the refrigerant suction chamber 13a is sucked into the cylinders 11a, and is discharged into the refrigerant discharge chamber 13b. At this time, a refrigerant sucked into the compressor body 10 through the refrigerant suction port 12a in the second housing 12 passes through a gap of the motor 30, flowing into the first housing 11 via the communication holes 15a and the bearing 15b in the intermediate plate 15, and is sucked into the refrigerant suction chamber 13a through the refrigerant passages 11b in the first housing 11 and the communication hole 28b in the spherical body supporting member 28. In this case, since a lubricating oil is mixed with the refrigerant, not only the motor 30 and movable parts such as the bearing 15b but also a sliding part etc. of the spherical body 26 are lubricated. Also, though in a small amount, the refrigerant flows between the cylinder 11a and the piston 21, so that these elements are also lubricated.

The above-described electric compressor is used for a refrigeration circuit using a carbon dioxide refrigerant in a vehicular air conditioner. In this case, comparing with a flon refrigerant (R134a), the carbon dioxide refrigerant has a pressure of about 10 times in the refrigeration cycle.

Thus, according to the electric compressor of this embodiment, the rotational motion of the inclined plate 23 having a predetermined fixed angle of inclination is converted to swinging motion of the swing plate 24 that swings while the rotation thereof is regulated, and the pistons 21 are driven by the swinging motion of the swing plate 24, so that a construction having no sliding part due to the rotation of the inclined plate 23 can be provided. As a result, even under severe service conditions such as high load and poor lubricating condition using the carbon dioxide refrigerant, the durability can be improved. Therefore, high-efficiency compression performance due to the piston type can be obtained, and high durability and high efficiency can be realized by a low-cost construction, so that this electric compressor is very advantageous in realizing a construction for using the carbon dioxide refrigerant.

Also, the refrigerant sucked into the compressor body 10 is sucked into the refrigerant suction chamber 13a in the cylinder head 13 after flowing through not only the motor 30 and the movable parts such as the bearing 15b but also the sliding part etc. of the spherical body 26, so that the movable parts and sliding parts can surely be lubricated by the refrigerant with which a lubricating oil is mixed, and thereby high durability can be realized even under severe lubricating conditions in the case where the carbon dioxide refrigerant is used. In this case, by the buffering action at the time when the refrigerant flows through the movable parts and sliding parts, the pulsation of refrigerant on the suction side can be damped. Therefore, the suction pressure pulsation, which easily occurs in a reciprocating compressor such as the compressor of this embodiment, can be reduced significantly, and hence a refrigeration cycle producing very low noise can be realized.

Furthermore, the refrigerant suction chamber 13a is formed in the central portion of the cylinder head 13, and the refrigerant discharge chamber 13b having a high pressure is formed in a ring form around the refrigerant suction chamber 13a, so that the surface area of the refrigerant discharge chamber 13b can be decreased as compared with the case where the refrigerant discharge chamber 13b is formed in the central portion of the cylinder head 13, and thus a force caused by the sum of pressures of refrigerant applied to the wall surface of the compressor body 10 can be reduced. Therefore, a construction of low strength can be used, which can reduce the weight and cost.

Also, the inclined plate 23 is attached to one end of the drive shaft 22 and the motor 30 is arranged on the other end side of the drive shaft 22, and the drive shaft 22 is supported by only the bearings 15b and 22a arranged on the other end side of the inclined plate 23, so that a part for supporting the drive shaft 22 is not needed on one end side of the drive shaft 22, that is, on one end side of the inclined plate 23, and hence the assembling ability can be improved and the construction can be simplified. For example, after the pistons 21, the swing plate 24, and the like have been assembled on the first housing 11 side, and the motor 30, the drive shaft 22 to which the inclined plate 23 has been attached, and the intermediate plate 15 have been assembled on the second housing 12 side, these two assemblies are connected to each other by the bolts 11c, by which the assembling work can be performed very easily.

In this case, since the intermediate plate 15 having the bearing 15b for the drive shaft 22 is provided between the housings 11 and 12, the thrust force of the inclined plate 23 and the radial force of the drive shaft 22 can be received by the intermediate plate 15 fixed surely between the housings 11 and 12, so that the durability can be improved. Since the drive shaft 22 can be supported with a high strength by the intermediate plate 15, the bearing 22a on the other end side of the drive shaft 22 can also be omitted.

FIG. 4 is a side sectional view of an electric compressor in accordance with another embodiment of the present invention. This embodiment differs from the above-described embodiment in the configuration of the drive shaft, inclined plate, and spherical body. Explanation is given by applying the same reference numerals to elements equivalent to those in the above-described embodiment.

Specifically, in this embodiment, an inclined plate 40 is provided so that one end side of a drive shaft 41 penetrates it, and the other end of the drive shaft 41 is supported by a bearing 41a. Also, one end of the drive shaft 41 is rotatably supported by a spherical body 42 provided on one end side of the drive shaft 41, and the inclined plate 40 is swingingly supported. In this embodiment, a structure corresponding to the intermediate plate 15 in the above-described embodiment is not provided, and the housings 11 and 12 are connected directly to each other.

As in the case of the above-described embodiment, the inclined plate 40 has an inclined surface 40a, which makes a predetermined angle of inclination, on one end side thereof. Also, one end side of the drive shaft 41 penetrates the central portion of the inclined plate 40 so that the inclined plate 40 rotates integrally with the drive shaft 41.

As the bearing 41a for supporting the other end of the drive shaft 41, an angular ball bearing that simultaneously regulates the axial and radial movement of the drive shaft 41 is used. However, the bearing 41a may be formed by thrust and journal bearings.

As in the case of the above-described embodiment, the spherical body 42 is slidably supported by the spherical body supporting member 28. In this case, the spherical body 42 has a hole in which one end side of the drive shaft 41 is inserted, and is connected to one end side of the drive shaft 41.

According to this embodiment, one end side of the drive shaft 41 is rotatably supported by the spherical body 42 and the spherical body supporting member 28, and the swing plate 24 is swingingly supported by the spherical body 42. Therefore, a special-purpose bearing for supporting one end side of the drive shaft 41 and an intermediate plate need not be provided, so that the number of parts can be decreased.

In this case, supporting means for supporting one end side of the drive shaft 41 is formed by the spherical body 42 engaging slidably with the central portion of the swing plate 24 and the spherical body supporting member 28 slidably supporting the spherical body 42, and one end of the drive shaft 41 is connected to the spherical body 42, so that the rotating motion of the drive shaft 41 and the swinging motion of the swing plate 24 can be achieved by the common spherical body 42. Therefore, the mechanism for supporting one end side of the drive shaft 41 can be made simple in construction and small in size.

INDUSTRIAL APPLICABILITY OF THE INVENTION

As described above, according to the present invention, since the electric compressor can have a construction in which a sliding part due to the rotation of the inclined member is not provided, the durability can be improved even under severe service conditions such as high load and poor lubricating condition using a carbon dioxide refrigerant. Therefore, high-efficiency compression performance due to the piston type can be obtained, and high durability and high efficiency can be realized by a low-cost construction, so that this electric compressor is very advantageous in realizing a construction for using the carbon dioxide refrigerant.

Also, according to the present invention, a force caused by the sum of pressures of refrigerant applied to the wall surface of the compressor body can be reduced. Therefore, a construction of low strength can be used, which can reduce the weight and cost and further improve the durability.

Also, since the movable parts and sliding parts in the compressor body can surely be lubricated, high durability can be realized even under severe lubricating conditions in the case where the carbon dioxide refrigerant is used. Also, the pulsation of refrigerant on the suction side can be damped. Therefore, the suction pressure pulsation, which easily occurs in a reciprocating compressor, can be reduced significantly, and hence a refrigeration cycle producing very low noise can be realized.

Also, according to the present invention, since a part for supporting the drive shaft need not be provided on one end side of the inclined member, the assembling ability can be improved and the construction can be simplified.

Also, according to the present invention, since the thrust force of the inclined member and the radial force of the drive shaft can be received by the intermediate plate fixed surely between the housings, the durability can be improved. In this case, since the drive shaft can be supported with a high strength by the intermediate plate, the drive shaft can be supported by the intermediate plate only, so that other bearings are omitted, and hence the construction can further be simplified.

Also, according to the present invention, since a special-purpose bearing for supporting one end side of the drive shaft need not be provided, the number of parts can be decreased.

Also, according to the present invention, since the rotating motion of the drive shaft and the swinging motion of the swing plate can be achieved by the common spherical body, the mechanism for supporting the drive shaft can be made simple in construction and small in size.

Claims

1. An electric compressor comprising a plurality of cylinders arranged in the circumferential direction on one end side of a compressor body; a plurality of pistons reciprocating in said cylinders; a drive shaft for driving said pistons; and a motor for rotating said drive shaft, so that a refrigerant is sucked and discharged by reciprocating said pistons in the axial direction of said drive shaft, characterized in that

said electric compressor further comprises:

an inclined member which has an inclined surface, making a predetermined fixed angle of inclination with respect to said drive shaft, at one end thereof and rotates integrally with said drive shaft; and

a swing member to which said pistons are connected via a connecting member having a universal joint at a predetermined position in the circumferential direction and which reciprocates said pistons by swinging along the inclined surface of said rotating inclined member while the rotation thereof is regulated, and

a carbon dioxide refrigerant is used as said refrigerant.

2. The electric compressor according to claim 1, further comprising

a refrigerant suction chamber for accommodating the refrigerant sucked into said cylinders and a refrigerant discharged chamber into which the refrigerant is discharged from said cylinders are provided on one end side of said compressor body, and

said refrigerant suction chamber is formed in a central portion on one end side of said compressor body, and said refrigerant discharge chamber is formed in a ring from around said refrigerant suction chamber.

3. The electric compressor according to claim 1, further comprising a refrigerant suction port is provided on the other end said of said compressor body so that a refrigerant sucked through said refrigerant suction port flows in said compressor body and is sucked into said cylinders.

4. The electric compressor according to claim 1, wherein

said inclined member is provided at one end of said drive shaft, and said motor is arranged on the other end side of said drive shaft; and

said drive shaft is supported by only at least one bearing arranged on the other end side of said inclined member.

5. The electric compressor according to claim 4, further comprising

a first housing arranged on the side of said pistons, swing member, and inclined member and a second housing arranged on the side of said motor are provided, and

an intermediate plate having a bearing for said drive shaft is provided between said housings.

6. The electric compressor according to claim 1, wherein

said inclined member is provided so that one end side of said drive shaft penetrates said inclined member, and said motor is arranged on the other end side of said drive shaft;

the other end of said drive shaft is supported by a bearing; and

supporting means which rotatably supports one end of said drive shaft and swingingly supports said swing member is provided on one end side of said drive shaft.

7. The electric compressor according to claim 6, wherein said supporting means is formed by a spherical body to which one end of said drive shaft is connected and which engages slidably with a central portion of said swing member and a spherical body supporting member for slidably supporting said spherical body.

8. The electric compressor according to claim 2, wherein

said inclined member is provided at one end of said drive shaft, and said motor is arranged on the other end side of said drive shaft; and

said drive shaft is supported by only at least one bearing arranged on the other end side of said inclined member.

9. The electric compressor according to claim 8, further comprising

a first housing arranged on the side of said pistons, swing member, and inclined member and a second housing arranged on the side of said motor are provided, and

an intermediate plate having a bearing for said drive shaft is provided between said housings.

10. The electric compressor according to claim 3, wherein

said inclined member is provided at one end of said drive shaft, and said motor is arranged on the other end side of said drive shaft; and

said drive shaft is supported by only at least one bearing arranged on the other end side of said inclined member.

11. The electric compressor according to claim 10, further comprising

a first housing arranged on the side of said pistons, swing member, and inclined member and a second housing arranged on the side of said motor are provided, and

an intermediate plate having a bearing for said drive shaft is provided between said housings.

12. The electric compressor according to claim 2, wherein

said inclined member is provided so that one end side of said drive shaft penetrates said inclined member, and said motor is arranged on the other end side of said drive shaft;

the other end of said drive shaft is supported by a bearing; and

supporting means which rotatably supports one end of said drive shaft and swingingly supports said swing member is provided on one end side of said drive shaft.

13. The electric compressor according to claim 12, wherein said supporting means is formed by a spherical body to which one end of said drive shaft is connected and which engages slidably with a central portion of said swing member and a spherical body supporting member for slidably supporting said spherical body.

14. The electric compressor according to claim 3, wherein

said inclined member is provided so that one end side of said drive shaft penetrates said inclined member, and said motor is arranged on the other end side of said drive shaft;

the other end of said drive shaft is supported by a bearing; and

supporting means which rotatably supports one end of said drive shaft and swingingly supports said swing member is provided on one end side of said drive shaft.

15. The electric compressor according to claim 14, wherein said supporting means is formed by a spherical body to which one end of said drive shaft is connected and which engages slidably with a central portion of said swing member and a spherical body supporting member for slidably supporting said spherical body.

16. The electric compressor according to claim 2, further comprising a refrigerant suction port is provided on the other end said of said compressor body so that a refrigerant sucked through said refrigerant suction port flows in said compressor body and is sucked into said cylinders.

17. The electric compressor according to claim 16, wherein

said inclined member is provided at one end of said drive shaft, and said motor is arranged on the other end side of said drive shaft; and

said drive shaft is supported by only at least one bearing arranged on the other end side of said inclined member.

18. The electric compressor according to claim 17, further comprising

a first housing arranged on the side of said pistons, swing member, and inclined member and a second housing arranged on the side of said motor are provided, and

an intermediate plate having a bearing for said drive shaft is provided between said housings.

19. The electric compressor according to claim 16, wherein

said inclined member is provided so that one end side of said drive shaft penetrates said inclined member, and said motor is arranged on the other end side of said drive shaft;

the other end of said drive shaft is supported by a bearing; and

supporting means which rotatably supports one end of said drive shaft and swingingly supports said swing member is provided on one end side of said drive shaft.

20. The electric compressor according to claim 19, wherein said supporting means is formed by a spherical body to which one end of said drive shaft is connected and which engages slidably with a central portion of said swing member and a spherical body supporting member for slidably supporting said spherical body.