JPH0683971U - Swash plate type compressor - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a swash plate type compressor with good slidability between the swash plate and the shoe not only at startup but also during operation. [Structure] A plurality of radial grooves 51 are provided in a portion of an axial end surface of a swash plate 7 fixed to a rotary shaft 4 corresponding to a top dead center side of a piston 17. These grooves may be formed along a predetermined curve extending with a predetermined curvature in a direction intersecting on a line segment connecting a portion corresponding to the top dead center and a portion corresponding to the bottom dead center of the piston. The piston is slidably arranged in the cylinder bore 12 around the rotation axis.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a swash plate compressor, and more particularly, to improvement of slidability between a swash plate and a shoe.

[0002]

[Prior art]

 An example of this type of compressor is disclosed in Japanese Patent Publication No. 1-35190. The compressor includes a swash plate that is inclined with respect to the axis of the rotating shaft and is driven to rotate about the axis. A cylinder bore parallel to the axis is formed around the axis. That is, the cylinder bore is eccentric from the axial center. A piston is slidably arranged in the cylinder bore. A member called a shoe is interposed between the swash plate and the piston. The shoe is held by the piston and slides on the swash plate when it rotates. Here, a portion that comes into sliding contact with the shoe when the swash plate rotates is referred to as a sliding contact portion.

When the rotary shaft is rotationally driven, the swash plate rotates around the shaft center accordingly, causing the piston to reciprocate in the cylinder bore via the shoe. The result is a predetermined compression effect.

[0004]

[Problems to be solved by the device]

 During operation, the swash plate and shoe slide with a large load and a large speed, so it is difficult for an oil film to form here. In particular, at the time of start-up, sliding conditions equal to static friction force and non-lubrication overlap, and seizure and wear easily occur between the swash plate and the shoe. Not only is seizure not permitted, but wear is also a problem because it increases the clearance between the swash plate and the shoe, which causes increased noise.

Therefore, an object of the present invention is to provide a swash plate type compressor in which an oil film is easily formed between the swash plate and the shoe not only at the time of starting but also during operation.

[0006]

[Means for Solving the Problems]

 According to the present invention, a swash plate that is inclined with respect to the axis and is driven to rotate around the axis, a cylinder bore parallel to the axis, and a piston slidably arranged in the cylinder bore, In a swash plate compressor having the swash plate and a shoe interposed between the piston and held by the piston, only a portion of the axial end surface of the swash plate corresponding to the top dead center side of the piston. A swash plate type compressor having a plurality of radial grooves is provided in the compressor.

According to the present invention, the swash plate inclined with respect to the axis and driven to rotate about the axis, the cylinder bore parallel to the axis, and the cylinder bore slidably disposed. A swash plate compressor having a piston, a swash plate, and a shoe interposed between the piston and held by the piston, the axial end surface of the swash plate corresponding to the top dead center side of the piston. A swash plate compressor characterized in that only a portion is provided with a plurality of grooves extending in directions intersecting on a line segment connecting a portion corresponding to the top dead center of the piston and a portion corresponding to the bottom dead center thereof. Is obtained. The plurality of grooves are preferably symmetrically provided on both sides of the line segment with respect to the line segment. Each of the plurality of grooves preferably extends along a curve.

[0008]

【Example】

 1 to 3 show a swash plate type compressor according to an embodiment of the present invention. With reference to FIG. 1, this swash plate compressor is used, for example, in a refrigerating circuit of an automobile air conditioner, and includes a front cylinder block 1 and a rear cylinder block 2 abutted against the front cylinder block 1. The front cylinder block 1 and the rear cylinder block 2 together constitute a compressor body 3.

A rotary shaft 4 is inserted through the center of the compressor body 3. The rotary shaft 4 is rotatably supported by the front cylinder block 1 and the rear cylinder block 2 via radial bearings 5 and 6, respectively. A swash plate 7 tilted with respect to the axis of the rotary shaft 4 is fitted and fixed by a spring pin 8. Therefore, when the rotating shaft 4 is rotationally driven, the swash plate 7 is rotationally driven together with the rotating shaft 4 around the axis thereof. 9 and 11 are thrust bearings.

Each of the front cylinder block 1 and the rear cylinder block 2 is formed with a plurality of cylinder elements extending around the rotary shaft 4 in parallel with the axis. The cylinder elements of the front cylinder block 1 and the cylinder elements of the rear cylinder block 2 are in one-to-one correspondence and communicate with each other to form a cylinder bore 12. Therefore, the compressor body 3 has a plurality of cylinder bores 12 around the rotary shaft 4.

A front discharge passage 13 and a rear discharge passage 14 are formed between the cylinder bores 12 in the front cylinder block 1 and the rear cylinder block 2, respectively. The front discharge passage 13 and the rear discharge passage 14 communicate with a common passage 16 formed in a discharge flange 15 connected to the compressor body 3.

A piston 17 is slidably arranged in each cylinder bore 12 in parallel with the axis. The piston 17 has a void in the central portion in the axial direction, and the peripheral portion of the swash plate 7 is inserted into this void. A shoe 18 made of a ferrous material is interposed between both axial surfaces of the swash plate 7 and the inner surface of the cavity of the piston 17. The shoe 18 has a hemispherical shape defined by a spherical surface portion and a flat surface portion, and is held by the piston 17 in a state where the spherical surface portion is in contact with a spherical concave surface 19 formed on the piston 17. The flat portion of the shoe 18 is in contact with the swash plate 7. When the swash plate 7 is rotated, a part of each of both surfaces in the axial direction is in sliding contact with the shoe 18.

Further, a front housing 23 and a rear housing 24 are provided on both axial end surfaces of the compressor body 3 via a front valve plate assembly 21 and a rear valve plate assembly 22. The front housing 23 forms a front suction chamber 25 near the axis and a front discharge chamber 26 around the front suction chamber 25. Further, inside the front housing 23, shaft sealing devices 27 and 28 are provided. One of the shaft sealing devices 27 rotatably supports the rotating shaft 4. The other 28 of the shaft sealing device substantially seals the gap between the rotary shaft 4 and the front housing 23. The rear housing 24 forms a rear suction chamber 31 near the axis and a rear discharge chamber 32 around the rear suction chamber 31.

The front valve plate assembly 21 includes a front valve plate 33, and a front intake valve 34 and a front discharge valve 35 on both sides of the front valve plate 33. The front valve plate 33 includes a front suction hole 36 that communicates the front suction chamber 25 with the cylinder bore 12, a front discharge hole 37 that communicates the front discharge chamber 26 with the cylinder bore 12, and a front discharge chamber 26 with a front discharge passage. 13 has a front communication hole 38 communicating with 13. The front intake valve 34 faces the front intake hole 36. The front discharge valve 35 faces the front discharge hole 37.

The rear valve plate assembly 22 includes a rear valve plate 41 and a rear intake valve 43 and a rear discharge valve 42 on both sides of the rear valve plate 41. The rear valve plate 41 includes a rear suction hole 44 that communicates the rear suction chamber 31 with the cylinder bore 12, a rear discharge hole 45 that communicates the rear discharge chamber 32 with the cylinder bore 12, and a rear discharge chamber 32 with the rear discharge passage 14. And a rear communication hole 46 communicated with the. The rear intake valve 43 faces the rear intake hole 44. The rear discharge valve 42 faces the rear discharge hole 45.

When the rotary shaft 4 is rotationally driven by an automobile engine, electric motor, or the like (not shown), the swash plate 7 rotates around the shaft center accordingly, and the piston 17 is rotated in the cylinder bore 12 via the shoe 18. Reciprocate in the direction. According to the reciprocating movement of the piston 17, the compression action of the refrigerant gas is obtained as described below. The refrigerant gas usually contains lubricating oil.

The refrigerant gas is supplied to the front and rear suction chambers 25 and 31 through passages (not shown), and is sucked into the cylinder bore 12 through front and rear suction holes 36 and 44. After being compressed by the piston 17 in the cylinder bore 12, the refrigerant gas is discharged into the front and rear discharge chambers 26 and 32 through the front and rear discharge holes 37 and 45. Further, the refrigerant gas is sent to the common passage 16 through the front and rear communication holes 38 and 46 and the front and rear discharge passages 13 and 14.

2 (a), (b) and FIG. 3, a plurality of grooves 51 are formed only on a portion corresponding to the top dead center side of the piston 17 on each of both axial surfaces of the swash plate 7. To form. These grooves 51 are radially arranged at equal intervals in the circumferential direction. Each of the grooves 51 extends linearly. The portion corresponding to the bottom dead center side of the piston 17 is a flat surface. The cross-sectional shape of the groove 51 is not limited to the semicircular shape shown in FIG. 3, and various shapes can be adopted.

According to this, the lubricating oil contained in the refrigerant gas is retained in the groove 51. Therefore, during operation, an oil film is quickly formed between the swash plate 7 and the shoe 18, so that the lubricity is improved and the problems of heat generation, seizure, and wear are eliminated. Further, since the wear can be prevented, the noise due to the increase in the gap between the swash plate 7 and the shoes 18 can be reduced.

4A and 4B show a modification of the swash plate 7. In this swash plate 7, each of the plurality of grooves 51 extends with a predetermined curvature in a direction intersecting on a line segment 52 connecting a portion corresponding to the top dead center and a portion corresponding to the bottom dead center of the piston 17. It is formed along a predetermined curve. The direction of this predetermined curve is the direction along the locus of the shoe 18 on the axial end surface of the swash plate 7. Moreover, these grooves 51 are provided on both sides of the line segment 52 so as to be symmetrical with respect to the line segment 52.

According to this, even if the number of the grooves 51 is small, a state in which the sliding surface of the shoe 18 is constantly in one of the grooves 51 is obtained, and continuous lubrication is possible. Further, good lubricity is maintained regardless of which direction the rotating shaft 4 rotates, that is, whether the rotating shaft 4 operates in either the forward rotation direction or the reverse rotation direction.

[0022]

[Effect of device]

 As described above, according to the present invention, it is possible to provide the swash plate type compressor in which a good oil film is formed between the swash plate and the shoe not only at the time of startup but also during operation. Therefore, good lubricity is maintained between the swash plate and the shoe, and problems such as heat generation, seizure, and wear between the two are eliminated.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a swash plate type compressor according to an embodiment of the present invention.

2 shows a combination of a swash plate and a rotary shaft included in the swash plate compressor of FIG. 1, (a) being a view in the direction of arrow a of FIG. 1,
(B) is a view on arrow b in FIG. 1.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 shows a modified example of a combination of a swash plate and a rotary shaft,
FIG. 1A is a view in the direction of arrow a in FIG. 1, and FIG. 1B is a view in the direction of arrow b in FIG. 1.

[Explanation of symbols]

 3 Compressor body 4 Rotating shaft 7 Swash plate 12 Cylinder bore 17 Piston 18 Shoe 51 Groove 52 Line segment

Claims (4)

[Scope of utility model registration request] 1. A swash plate inclined with respect to an axis and driven to rotate about the axis, a cylinder bore parallel to the axis, a piston slidably arranged in the cylinder bore, and the inclination. In a swash plate compressor having a plate and a shoe held between the piston and held by the piston, a plurality of radial patterns are provided on a portion of the axial end surface of the swash plate that corresponds to the top dead center side of the piston. A swash plate compressor characterized by having grooves. 2. A swash plate inclined with respect to an axis and driven to rotate around the axis, a cylinder bore parallel to the axis, a piston slidably arranged in the cylinder bore, and the inclination. In a swash plate compressor having a plate and the shoe interposed between the piston and held by the piston, a portion of the axial end surface of the swash plate that corresponds to the top dead center side of the piston is A swash plate compressor having a plurality of grooves extending in directions intersecting with each other on a line segment connecting a portion corresponding to top dead center and a portion corresponding to bottom dead center. 3. The swash plate compressor according to claim 2,
The swash plate compressor, wherein the plurality of grooves are provided on both sides of the line segment so as to be symmetrical with respect to the line segment. 4. The swash plate compressor according to claim 2,
A swash plate compressor, wherein each of the plurality of grooves extends along a curved line.