KR0143574B1 - Swash plate type compressor - Google Patents

Abstract

Reduce vibrations and extend the life of thrust bearings.

Both pressure-receiving seats 51 and 31 which clamp at least one of the thrust bearings 6A and 6B fitted in front and rear of the swash plate 5 support the orbital center circle PC of the one thrust bearing 6B. Since the at least one pressure receiving seat 51 is formed in a levee shape having an outer diameter smaller than the outer diameter of the race 61 to impinge on the collision, the actuating surface acts on the raceway surface of the thrust bearing 6B. The weight is reduced, and the contents thereof are improved.

In addition, in the pressure receiving sheet 251 formed in the boss portion of the swash plate 205, an area of almost a circular shape corresponding to the inclination angle phase of the swash plate 205 in which the moment acting on the pressure receiving sheet 51 is maximum is By engraving as 251a, the unbalanced load acting on the raceway surface of the thrust bearing 206b is eliminated, and the durability thereof is improved.

Description

Double head swash plate compressor

1 is a partial sectional view showing a main part of a compressor according to an embodiment of the present invention.

2 is a partial sectional view showing a modification of the embodiment of the present invention.

3 is a partial cross-sectional view showing another modification of the present invention.

4 is a partial sectional view showing yet another embodiment of the present invention.

5 is a sectional view showing the main part of a compressor according to another embodiment of the present invention.

6 is a sectional view of an essential part showing a modification of still another embodiment of the present invention.

7 is an enlarged explanatory diagram showing the crowning effect of a thrust bearing;

8 is an enlarged explanatory diagram briefly showing a load absorbing function of a conventional thrust bearing.

9 is a cross-sectional view showing the entirety of a conventional compressor.

10 is a sectional view showing a main portion of a compressor according to an embodiment of the present invention.

11 is a sectional view of an essential part showing still another modification of the present invention.

Fig. 13 is a sectional view showing a main part of a compressor according to another embodiment of the present invention.

Fig. 14 is a sectional view of principal parts showing a modification of still another embodiment of the present invention.

FIG. 15 is an enlarged explanatory view briefly showing the load absorbing function of the conventional thrust bearing; FIG.

Fig. 16 is a sectional view showing the whole of a conventional compressor.

17 is a sectional view showing the main part of a compressor according to the embodiment of the present invention;

18 is a cross-sectional view showing a swash plate according to an embodiment of the present invention.

19 is a side view showing a swash plate according to an embodiment of the present invention.

20 is a sectional view showing a modification of the swash plate according to the embodiment of the present invention.

21 is a sectional view of principal parts of a compressor according to another embodiment of the present invention.

Fig. 22 is a sectional view of principal parts showing a modification of still another embodiment of the present invention.

Fig. 23 is a sectional view showing an overall view of a conventional compressor.

FIG. 24 is an enlarged explanatory view schematically showing a load absorbing function of a conventional thrust bearing. FIG.

＊ Explanation of symbols for main parts of drawing

1,101,201: Drive shaft

2,102,202,20,120,220: all cylinder blocks

3,103,203: Rear cylinder block 5,105,205,50,150,250: Swash plate

31,131,231,51,151,251: Pressure Receiving Seat

6A, 106A, 206A, 6B, 106B, 206B: Thrust Bearing

61,161,261: inner race 62,162,262: outer race

8,108,208: washers

[Industrial use]

The present invention relates to a double head swash plate compressor, and more particularly, to an improvement in a thrust bearing portion for accommodating the swash plate's celebration.

[Prior art]

Many of the double-headed swash plate type compressors supplied for vehicle air conditioning are swash plates 12 on the drive shaft 11 supported by a pair of cylinder blocks 10A and 10B, as disclosed in Japanese Patent Laid-Open Publication No. 64-63669. Thrust bearing 13 fitted with the swash plate 12 before and after the swash plate 12 is fastened together by bolts 16 through the two housings 14 and 15 which close both the embodiments and the outer end thereof. It is attached by the thing. The axial interference due to the tightening is absorbed by the elastic deformation generated in the race of the thrust bearing 13, and the inner race 13a is formed at both boss portions of the swash plate 12 near its outer diameter. When the collision contact with the annular pressure receiving sheet 12a formed on the side, the outer race 13b is in contact with the annular pressure receiving sheet 10a formed at the support of the cylinder blocks 10A and 10B near its inner diameter. It is comprised (FIG. 9).

[Problems to Solve Invention]

The axial load generated by the compression reaction force of the refrigerant gas due to the rotation of the swash plate 12 is absorbed by the thrust bearing 13, but both of these thrust bearings 13 are annular pressure receiving sheets 10a of the different diameters described above. The spring means S are actually provided on both sides of the swash plate 12 that receives the variable load, as shown in FIG. The result is intervening. That is, the moment in which the compression reaction force acts on the swash plate 12 induces an unstable vibration in the swash plate 12 by the mutual buffering of the spring means S. In particular, a strong frequency component of permeability generated at high rotation speed prevents noise interference. Encourage further

On the other hand, as disclosed in Japanese Utility Model Publication No. 54-170410, both boss portions of the swash plate and both support portions of the cylinder block both form a flat pressure receiving sheet so that both thrust bearings are sandwiched in the rigid. It can be seen, however, that in this clamping type, when a moment based on compression reaction acts on the swash plate, the inner race, which impinges on the swash plate pressure bearing seat and all planes, digs into the outer end of the roller. As a result of being pressurized, there is a problem that such an unbalanced load applied to the rollers not only causes the loss of thrust bearings to be extremely fast but also affects vibration, noise, or power loss.

The present invention aims to solve the problem of reducing the vibration and the noise and at the same time reducing the life of the thrust bearing.

[Means for solving the problem]

The present invention to solve the above problems in the two-head swash plate type compressor which is sandwiched between the pressure receiving seat formed on the boss portion of the swash plate moving with the drive shaft and the pressure receiving seat formed on the pair of cylinder blocks, respectively The positive pressure receiving seat which sandwiches at least one thrust bearing has a pressure receiving surface including a raceway center circle of the one thrust bearing, and a race outer diameter at which the at least one pressure receiving seat is impinged on the raceway. It is formed in the shape of a levee having a smaller outer diameter.

The pressure-receiving sheet is formed in a truncated corpus form that retains at least one of the micro-gaps in a wide formation outward between the races colliding with each other. In addition, in the form of supporting the thrust bearings disposed on both sides of the swash plate together with the rigid, it is preferable to apply the above-described input seat structure to both thrust bearings.

The invention according to claim 12 is a position in which a moment acting on the pressure receiving sheet with respect to a plane orthogonal to the driving shaft center of the pressure receiving sheet formed on the boss portion of the swash plate holding at least one thrust bearing is maximized. It is characterized by being installed obliquely in the direction of.

The present invention provides a double head swash plate type compressor formed by sandwiching a thrust bearing between a pressure receiving sheet formed on a boss of a swash plate moving together with a drive shaft and a pressure receiving sheet formed on a pair of cylinder blocks. In the pressure receiving sheet formed in the boss portion of the swash plate to sandwich the at least one thrust bearing, a substantially semi-annular region corresponding to the inclination angle phase of the swash plate is maximized. It is characterized by being square as a surface. In addition, it is preferable to apply the pressure receiving seat configuration of the swash plate boss portion to both thrust bearings in the case of supporting the thrust bearings disposed on both sides of the swash plate together with the rigid.

In a preferable state, the outer diameter of the said one pressure receiving seat is set equal to the track outer diameter of the said one thrust bearing.

In a preferable state, the outer diameter of the said one pressure receiving seat is set smaller than the track outer diameter of the said one thrust bearing.

In a preferable state, the inner diameter of the one pressure receiving seat is set larger than the track inner diameter of the one thrust bearing.

In a preferred state, the cross-sectional shape of the one pressure receiving sheet is formed as a convex curved surface in collision contact with the race at the raceway center circle.

In the preferred state, the one pressure receiving seat configuration is applied to the pressure receiving seat formed in the boss portion. In addition, it is preferable to apply the pressure receiving sheet to both thrust bearings in a type in which the thrust bearings disposed on both sides of the swash plate are clamped together in the rigid support.

In the preferred state, the other thrust bearing which is supported by the both pressure receiving seats is provided with a shock absorbing function for absorbing the axial load.

In a preferred state, the cushioning function is the elastic deformation capacity of the race itself brought by annular pressure bearing sheets of different diameters which sandwich the other thrust bearing.

In a preferred state, the damping function is an elastic deformation capacity inherent in the spring member sandwiched between the other thrust bearing and the cylinder block.

In a preferred state, the surface to be coated is engraved in a step shape.

In a preferred state, the surface to be coated is inscribed in an inclined shape toward the outer circumferential side.

In the preferred state, the other thrust bearing which is supported by the both pressure receiving seats is provided with a shock absorbing function for absorbing the axial load.

In a preferred state, the cushioning function is the elastic deformation capacity of the race itself brought by annular pressure bearing sheets of different diameters which sandwich the other thrust bearing.

[Action]

Thus, when the moment based on the compression reaction force acts on the swash plate, the thrust bearing is clamped to the rigid support (the opposing opposing pressure bearing seat has a pressure bearing surface including the orbital center circle of the thrust bearing). A strong unloading load is exerted on the pressure bearing sheet and the raceway to impinge against it (surface area rolled by the roller), but at least one outer diameter smaller than the race outer diameter at which one pressure bearing sheet impinges, preferably. Is set equal to or smaller than the track outer diameter of the thrust bearing and the clearance between the outer circumferential side of the race is secured, so that the eccentric load acting on the track surface is reasonably attenuated.

In addition, when the inner diameter of the pressure receiving seat is set larger than the inner diameter of the thrust bearing, and the same clearance is secured between the race circumferential side surface, the moment fluctuation can be effectively absorbed by the extremely small bending occurring in the race.

In addition, the cross-sectional shape of the at least one pressure receiving sheet is formed in a convex curved surface which collides with the race at the center of the raceway, and acts on the inner and outer circumferential regions of the raceway surface in macroscopic contact with the race. Even if the load difference is reduced to the extreme and the fluctuation moment acts on the swash plate, the fluctuating load can be effectively absorbed by the extremely small bending caused by the race based on the collisional contact of the convex surface.

In the case where one of the thrust bearings sandwiched in this way is provided with a shock absorbing function for absorbing the axial load to the other thrust bearing, interference during assembly of the compressor is carefully absorbed by the shock absorbing function of the other thrust bearing. In addition, even when the moment acts on the swash plate based on the compression reaction force during the operation of the compressor, the axial load that one thrust bearing held by the rigid effectively suppresses the unstable vibration of the swash plate due to its rigidity is different. It is absorbed satisfactorily by the buffer function given to the thrust bearing of the side.

Therefore, when the moment based on the compression reaction force acts on the swash plate, the thrust bearing is clamped to the rigid support (the two opposing pressure receiving seats are in contact with the thrust bearing on a flat surface). Since the moment is received, a strong lateral load is exerted on both the bearing seat and the races that impinge against it, especially on the outer circumferential region of the raceway surface (rolling surface), but at least one pressure bearing seat is truncated conical. Since a small gap is formed between the race formed and the collision-joined race, the receiving moment is divided into a radial bearing supporting the drive shaft, so that the lateral load acting on the raceway surface of the thrust bearing Reasonably reduced.

In addition, even if the pressure receiving sheet formed on the boss portion of the swash plate supporting the at least one thrust bearing is inclined in the direction of the position where the moment acting on the pressure receiving sheet is maximized with respect to the plane perpendicular to the driving shaft center. Since a small wide gap is secured between the joining races toward the nearly starting point position of the swash plate, the unloading load acting on the raceway surface is similarly reduced.

In the pressure receiving sheet formed in the boss portion of the swash plate, the area of the return phase where the moment acting in particular is maximized is engraved as the surface to be drawn, so that a gap is maintained between the races to impinge on the driving shaft, so that the intake of the acting moment supports the drive shaft. The load on the thrust bearing is inevitably reduced. In addition, since the load is always uniformly received at both lines of the residual effective pressure bearing which forms the return phase regardless of the magnitude of the load, it is possible to almost eliminate the side load acting on the track surface of the thrust bearing.

EXAMPLE

Hereinafter, embodiments of the present invention will be described in detail with reference to FIG. In addition, since it does not change especially about the whole structure of a compressor, detailed illustration is abbreviate | omitted.

In FIG. 1, reference numeral 1 denotes a drive shaft supported by inserting a radial bayrun 4 into a cylinder block 2 at a front side and a cylinder block 3 at a rear side of the swash plate 5 mounted on the drive shaft 1. Thrust bearings 6A and 6B are fitted in the front and rear sides, and both thrust bearings 6A and 6B are pressurized seats and both cylinder blocks formed on both boss portions of the swash plate 5 by tightening together with the conventional through bolts. It is clamped between the pressure receiving seats formed in (2,3).

Means for pinching of the thrust bearings 6A and 6B, which is the most characteristic configuration of the present invention, will be described in detail below, but in this embodiment, both types of thrust bearings 6A and 6B are sandwiched and supported by the rigid. Is a form in which both opposing pressure receiving seats have a pressure receiving surface including an orbital center circle PC and both are of the same configuration, and therefore only the thrust bearing 6B will be described.

The thrust bearing 6B consists of an inner race 61, an outer race 62, a roller 63 and a supporter not shown, and the flat pressure bearing seat 31 formed in the cylinder block 3 is formed of the outer race 62. The pressure receiving sheet 51 formed on the boss portion of the swash plate 5 is formed in an embankment shape having an outer diameter smaller than the outer diameter of the inner race 61 and collides with the entire side surface. The necessary play is secured between the outer circumferential side surface of the inner race 61. In addition, the most preferable form of the pressure receiving seat 51 is to be about the same as the orbital outer diameter OD of the thrust bearing 6B as shown in the outer diameter, but can be set smaller than the same orbital outer diameter OD. . In addition, such a characteristic configuration of the pressure receiving sheet 51 is not limited to the pressure receiving sheet 51 formed at the boss portion of the swash plate 5, but this is formed in the cylinder block 3 as shown in FIG. It may be applied to the pressure receiving sheet 31 or may be applied to both of the pressure receiving sheets 51 and 31.

FIG. 3 shows a constitution that also has an inner diameter in addition to the characteristic constitutions of the outer diameters of the pressure receiving seats 51 and 31, the inner diameter of which is set larger than the orbit inner diameter BD of the thrust bearing 6B. A clearance similar to that of the outer circumferential side described above is secured between the boss portion of the swash plate 5 and the inner circumferential side of the inner race 61.

Therefore, when the moment based on the compression reaction force acts on the swash plate 5, the pressure bearing the thrust bearing, for example 6B, is supported by the rigid (the opposing opposite pressure receiving seat includes the orbital center circle PC of the thrust bearing). In the form of a bearing surface), in particular the outer circumference of the raceway surface (surface portion rolled by the roller) via both the pressure bearing seats 51 and 31 and the inner race 61 and the outer race 62 which are in collisional engagement with it. The strong lateral load acts on the area, but the outer diameter smaller than the outer diameter of the inner race 61 to which the at least one pressure receiving sheet, for example, 51 impinges, preferably the track outer diameter OD of the thrust bearing 6B and Since the clearance is secured between the boss portion of the swash plate 5 and the outer circumferential side surface of the inner race 61 because it is set equally or smaller than that, the lateral load acting on the raceway surface is reasonably attenuated. do.

In addition, the inner diameter of the pressure receiving seat 51 is set larger than the raceway inner diameter BD of the thrust bearing 6B as shown in FIG. 3 so as to secure the same clearance between the inner circumferential side of the inner race 61. Can effectively absorb the moment fluctuation due to the extremely small bending occurring in the inner race 61.

In addition, with reference to FIG. 7, the pressure receiving seat formed in the cylinder block 3 is rotated in conjunction with the out race 62 when the swash plate 5 rotates in accordance with the operation of the compressor. 31), and the pressure receiving seat 31 absorbs moment fluctuations, which results in harmonious wear of the micron order (W ₁ ). On the other hand, the inner race 61 is harder to cause accompanying rotation in any way compared to the outer race 62, but the pressure formed in the boss portion of the swash plate 5 due to the extremely slight bending of the reduced interlaced 61 of the actual pressure receiving area. The backing sheet 51 also has a matching wear (W ₂ ) sufficient to absorb the moment variation, which exhibits a good cleaning effect.

4 shows another embodiment, in which the pressure receiving seat 51 formed on the boss portion of the swash plate 5 has its cross-sectional shape collided with the inner race 61 at the orbital center circle PC of the thrust bearing 6B. Since the contact surface is formed with the convex curved surface to maintain the linear contact with the inner race 61 macroscopically, the load difference acting on the inner and outer circumferential regions of the raceway surface is extremely reduced, and even when the fluctuating moment acts on the swash plate 5. Due to the extremely slight bending occurring in the inner race 61 based on the collision contact of the convex curved surface, the fluctuating load can be effectively absorbed similarly.

Another embodiment shown in FIGS. 5 and 13 is for example to support one of the thrust bearings 6B, 106B by means of a unique pressure bearing seat configuration as described above and the other thrust. The bearings 6A and 106A are provided with a shock absorbing function that also absorbs the axial load.

That is, a relatively large diameter annular pressure receiving seats 5a and 105a are formed in the boss portions of the swash plates 5 and 106 which sandwich the thrust bearings 6A and 106A so that the inner races 61 and 161 are formed near the outer diameter thereof. Collision-bonded with the annular pressure receiving seats 5a and 105a, while the cylinder blocks 2 and 102 are formed with relatively small diameter annular pressure receiving seats 2a and 102a so that the outer races 62 and 162 are close to their inner diameters. It is comprised so that it may collide with the annular pressure receiving sheet | seat 2a, 102a. In addition, in the present embodiment, the inner races 61 and 161 of both thrust bearings 6A, 6B, 106A and 106B have a larger diameter than the outer races 62 and 162 in view of the common function of the thrust bearings 6A and 106A and the parts. Formed.

Thus, when the two boss portions of the swash plate 5 are fitted together by the fastening members together including the two cylinder blocks 2 and 3 via the thrust bearings 6A and 6B, the annular pressure receiving seats 5a and 2a of different diameters are mounted. ), The elastic deformation occurs in the races 61 and 62 itself of the thrust bearing 6A, which is impingementally bonded to each other, and the axial interference is artfully absorbed by the rounding function, so that the clamping check force can be easily and stably adjusted.

When the compressor is operated, a moment based on the compression reaction force acts on the swash plate 5, but one of the thrust bearings 6B held by the rigid support the swash plate 5 stably with its rigidity and at the same time the pressure The seat seat configuration is also possible to absorb moment fluctuations and to reduce the lateral load acting on the thrust bearing 6B, and the fluctuating axial load is articulated by the buffer function applied to the other thrust bearing 6A. Is absorbed.

6 and 14 show another embodiment of the cushioning function imparted to the other thrust bearings 6A and 161A, wherein the front moss of the swash plates 50 and 150 has a flat pressure receiving sheet 50a or 150a. The outer races 62 and 162 are crash-bonded to the washer inner races 61 and 161, while the outer races 62 and 162 are crash-bonded to the washers 8 and 108 embedded in the cylinder blocks 20 and 120 via sheet metals 7,107. That is, the present embodiment does not obtain the shock absorbing function for absorbing the axial load by the thrust bearings 96A, 106A itself, but the elastic deformation inherent in the spring member (washer 8,108) geared between the cylinder blocks 20,120. It is characterized by the fact that it depends on and has the advantage that the selection of the spring constant is extremely easy.

In addition, although the above embodiment has described the configuration in which the shock absorbing function is provided to the front thrust bearing 6A, it may act on any one of the front and rear thrust bearings, and the spring member may be a coil spring and a roll in addition to the washer. Of course, it is also possible to employ springs.

The thrust bearing 106B is an inner race 161, an outer race 162, a roller 163 and an unillustrated support, and the flat pressure bearing seat B1 formed in the cylinder block 103 is the outer race 162. The pressure receiving sheet 151 formed on the boss portion of the swash plate 105 is formed in a truncated cone shape and has a small play with a wider outer space between the inner race 161 which is formed in a truncated cone. α) (about 0.02 to 0.5 °) is retained. In addition, such a characteristic configuration of the pressure receiving sheet 151 is not limited to the pressure receiving sheet 151 formed at the boss portion of the swash plate 105, as shown in FIG. If it is good to apply to the formed pressure receiving sheet 131, it is also possible to apply to both of the pressure receiving sheets 151 and 131, and to implement.

FIG. 12 shows a modification of the pressure receiving sheet 151, wherein the pressure receiving sheet 151 has an almost swash plate inclination angle in which a moment acting on the pressure receiving sheet 151 is maximized with respect to a plane perpendicular to the driving shaft center. And inclined in the same direction (exactly, the position direction of the angle slightly advanced in the rotational direction than the bottom dead center of the swash plate 105), and also in the present example, the swash plate 105 is disposed between the inner race 161 and the collision joint. Towards the dead point position, a small wide gap β (about 0.02 to 0.5 °) is secured.

Therefore, when the moment based on the compression reaction acts on the swash plate 105, the thrust bearing, for example, 106B is clamped to the rigid support (the two opposing pressure receiving seats collide with the thrust bearing on a flat surface). Since the moment is mainly supported by the thrust bearing 106B, the raceway surface (surface portion rolled by the rollers) is passed through both the pressure bearing seats 151 and 131 and the inner race 161 and the outer race 162 which collide with each other. In particular, a strong side load acts on the outer periphery, but at least one pressure receiving sheet, for example, 151 is formed in a truncated cone shape and has a wide play with a small gap α between the inner race 61 and the impact joint. Of the moment acting because it is retained is distributed in the radial bearing 104 supporting the drive shaft 101 and its thrust bear Of the offset load acting on the raceway surface of the (106B) it is reasonably reduced.

In addition, the pressure receiving sheet 151 formed on the boss portion of the swash plate 105 to sandwich the at least one thrust bearing 106B acts on the pressure receiving sheet 151 with respect to a plane orthogonal to the center of the drive shaft as shown in FIG. Even if it is inclined in the direction of the position where the moment to be maximized, a small wide beta (β) is secured toward the near dead point position of the swash plate 105 between the inner race 161 to be joined to the raceway surface, so that it acts on the raceway surface. The unbalanced load is similarly reduced.

On the other hand, the pressure receiving sheet 251 formed in the boss portion of the swash plate 205 is a swash plate 205 with a maximum moment acting on the pressure receiving sheet 251 as shown in FIGS. 18 and 18 more clearly. Nearly semi-circular region (shown by cross diagonal lines in the drawing) corresponding to the inclination angle phase (the angle α phase slightly advancing in the rotational direction from the bottom dead center P of the swash plate 205) as the surface to be 251a. Inscribed in a staircase shape, the necessary clearance C between the inner race 261 is secured.

FIG. 20 shows the deformed state of the to-be-printed surface 251a. The to-be-printed surface 251b in this embodiment is engraved in an inclined state with the semi-cyclic area toward the outer circumferential side and interposed with the inner race 261. The desired clearance C of wide shape is secured outside. Between the collision-bonded inner race 61 in which a semi-circular region of which the particularly effective moment of the pressure receiving sheet 251 formed in the boss portion of the swash plate 205 is maximized is engraved as the surface 251a or 251b. Since the clearances C 'and C are secured, the support of the acting moment is dispersed in the radial bayrun 204 supporting the drive shaft 201 and the load of the thrust bearing 206B is inevitably reduced.

In addition, since the load is always uniformly supported at both lines Q of the remaining effective pressure 251, which is semi-circular, regardless of the magnitude of the load, the single load acting on the track surface of the thrust bearing 206B. Can be almost eliminated.

Another embodiment shown in FIG. 21 is for example supported by one of the thrust bearings 206B being clamped to the rigid by a unique pressure bearing seat configuration as described above, and the other thrust bearing 206A also has an axial load. It gives a buffer function to absorb.

[Effects of the Invention]

Since the present invention described above has the structure described in the claims, the lateral load acting on the raceway surface of the thrust bearing is reduced, so that the durability of the thrust bearing can be further improved, and in particular, one side of the thrust bearing is supported. In the case where the pressure receiving sheet is formed apart from the race to impinge on the raceway center circle, the moment variation can be effectively absorbed by the slight warpage generated in the race.

Further, by providing a shock absorbing function for absorbing the axial load to the other side of the thrust bearing, it is possible to satisfactorily cope with not only the absorption of the axial interference during assembly but also the heat effect and the fluctuating axial load.

Claims (23)

In a two-head swash plate type compressor in which a thrust bearing is sandwiched between a pressure receiving seat formed on a boss of a swash plate moving together with a drive shaft and a pressure receiving seat formed on a pair of cylinder blocks, at least one thrust bearing is provided. Both of the pressure receiving seats sandwiched therein have a pressure receiving surface including a raceway center circle of one of the thrust bearings, and are formed in a bank shape having an outer diameter smaller than the outer diameter of the race that impinges the at least one pressure receiving sheet. Double head swash plate compressor characterized by one. The double head swash plate type compressor according to claim 1, wherein the outer diameter of the one pressure receiving seat is set equal to the outer diameter of the track of the one thrust bearing. The double head swash plate type compressor according to claim 1, wherein the outer diameter of the one pressure receiving seat is set smaller than the outer diameter of the track of the one thrust bearing. The double head swash plate type compressor according to any one of claims 1 to 3, wherein an inner diameter of the one pressure receiving seat is set larger than an inner diameter of the track of the one thrust bearing. In a two-head swash plate type compressor in which a thrust bearing is sandwiched between a pressure receiving seat formed on a boss of a swash plate moving together with a drive shaft, and a pressure receiving seat formed on a pair of cylinder blocks, at least one thrust bearing is provided. The both pressure bearing seats to be sandwiched have a pressure bearing surface comprising a raceway center circle of one of the thrust bearings, and the convex contacting the raceway at the raceway center circle with a cross-sectional shape of the at least one pressure bearing seat. Double head swash plate compressor characterized in that formed in a curved surface. The two-head swash plate type compressor according to any one of claims 1 to 3, wherein the one pressure receiving sheet is a pressure receiving sheet formed on the boss portion of the swash plate. The two-plate swash plate compressor according to claim 5, wherein the one pressure receiving sheet is a pressure receiving sheet formed on the boss portion of the swash plate. The two-head swash plate compressor according to any one of claims 1 to 3, wherein a shock absorbing function for absorbing an axial load is provided to the other thrust bearing sandwiched by the two pressure receiving seats. 6. A double head swash plate compressor according to claim 5, wherein a shock absorbing function for absorbing an axial load is provided to the other thrust bearing held by the two pressure receiving seats. The bilateral swash plate type compressor according to claim 8, wherein the cushioning function is an elastic deformation capacity of the race itself provided by annular pressure bearing sheets having different diameters for sandwiching the other thrust bearings. The bilateral swash plate type compressor according to claim 8, wherein the damping function is an elastic deformation capacity inherent to a spring member sandwiched between the other thrust bearing and the cylinder block. In a two-head swash plate type compressor in which a thrust bearing is sandwiched between a pressure receiving sheet formed on a boss portion of a swash plate operating together with a drive shaft and a pressure receiving sheet formed on a pair of cylinder blocks, at least one thrust bearing is provided. The two-head swash plate-type compressor, wherein the two pressure receiving seats to be clamped are formed in a truncated cone having a wide play with a small clearance between at least one of the races for impingement bonding. In a two-head swash plate type compressor in which a thrust bearing is sandwiched between a pressure receiving sheet formed on a boss portion of a swash plate operating together with a drive shaft and a pressure receiving sheet formed on a pair of cylinder blocks, at least one thrust bearing is provided. A double-headed swash plate type compressor characterized in that the pressure receiving sheet formed on the boss portion of the swash plate to be pinched is inclined slightly in the direction in which the moment acting on the pressure receiving sheet is maximized with respect to a plane orthogonal to the center of the drive shaft. . The double head swash plate type compressor according to claim 12, wherein a shock absorbing function for absorbing an axial load is provided to the other thrust bearing held by the two pressure receiving seats. The double head swash plate compressor according to claim 13, wherein a shock absorbing function for absorbing an axial load is provided to the other thrust bearing held by the two pressure receiving seats. 15. The bilateral swash plate compressor according to claim 14, wherein the buffer function is the elastic deformation capacity of the race itself provided by annular pressure bearing sheets having different diameters sandwiching the other thrust bearings. The bilateral swash plate type compressor according to claim 14, wherein the damping function is an elastic deformation capacity inherent to a spring member sandwiched between the other thrust bearing and the cylinder block. In a two-head swash plate type compressor in which a thrust bearing is sandwiched between a pressure receiving sheet formed on a boss portion of a swash plate operating together with a drive shaft and a pressure receiving sheet formed on a pair of cylinder blocks, at least one thrust bearing is provided. In the pressure receiving sheet formed in the boss portion of the swash plate to be pinched and supported, an almost semi-circular region corresponding to the inclination angle phase of the swash plate in which the moment acting on the pressure receiving sheet is maximized is engraved as the surface to be coated. Double head swash plate compressor. 19. The two-head swash plate type compressor according to claim 18, wherein the surface to be coated is engraved in a step shape. 19. The two-head swash plate type compressor according to claim 18, wherein the surface to be etched is inclined outwardly. The double head swash plate compressor according to any one of claims 18 to 20, wherein a shock absorbing function for absorbing an axial load is provided to the other thrust bearing held by the two pressure receiving seats. 22. The bilateral swash plate type compressor according to claim 21, wherein the cushioning function is an elastic deformation capacity of the race itself provided by annular pressure bearing sheets of different diameters which sandwich the other thrust bearing. 22. The bilateral swash plate type compressor according to claim 21, wherein the shock absorbing function is an elastic deformation capacity inherent to a spring member sandwiched between the thrust bearings and the cylinder block of the other side.