JP3013617B2 - Rotary shaft support structure for swash plate compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a double-ended piston bore accommodated in a plurality of pairs of cylinder bores arranged before and after a rotary shaft, and for controlling the rotational movement of a swash plate supported by the rotary shaft. The present invention relates to a rotary shaft support structure in a swash plate type compressor that converts a reciprocating motion of a double-headed piston and discharges refrigerant gas in a cylinder bore into discharge chambers before and after a cylinder block.

[0002]

2. Description of the Related Art Conventional swash plate type compressors (for example, see
No. 92587), the refrigerant gas in the compression chamber is discharged to the discharge chamber by the forward movement of the double-headed piston, and the refrigerant gas in the suction chamber is sucked into the compression chamber by the backward movement of the double-headed piston. A plurality of double-headed pistons are used and housed in cylinder bores arranged at equal angular intervals around the rotation axis. The compression chamber is connected to the discharge chamber via the discharge port, and is connected to the suction chamber via the suction port via the suction port. The discharge port is opened and closed by a discharge valve, and the refrigerant gas in the compression chamber is discharged to the discharge chamber while pushing the discharge valve. The suction port is opened and closed by a suction valve, and refrigerant gas in the suction chamber is sucked into the compression chamber while pushing down the suction valve. There is one discharge chamber before and after the cylinder block, and the discharge chamber communicates with an external discharge refrigerant gas pipe via a discharge passage in the cylinder block.

[0003] The arrangement interval of the cylinder bores is increased to such an extent that the required strength of the cylinder block can be secured. The size of the arrangement interval is proportional to the size of the arrangement radius of the cylinder bores. The arrangement radius increases as the arrangement interval increases, and the arrangement radius decreases as the arrangement interval decreases. However, the presence of the discharge passage in the cylinder block causes a reduction in the strength of the cylinder block. Therefore, as long as the configuration in which the discharge passage extends through the cylinder block is adopted, an extra space is required for the discharge passage, and it is difficult to make the compressor compact.

The rotation of the rotating shaft supporting the swash plate is supported by a pair of front and rear cylinder blocks via a pair of radial bearings. That is, the radial load on the rotating shaft is received by the cylinder block via the radial bearing. The thrust load on the rotating shaft is received by the cylinder block via a pair of front and rear thrust bearings sandwiching the swash plate. These bearing members are lubricated by lubricating oil flowing with the refrigerant gas.

However, the configuration in which the radial load and the thrust load on the rotating shaft are received via separate bearing members respectively complicates the assembling operation process. The present invention relates to a rotary shaft in a swash plate type compressor that receives a radial load and a thrust load on a rotary shaft with a single bearing member, can perform good lubrication of the bearing member, and can also downsize the entire compressor. It is intended to provide a support structure.

[0006]

According to the present invention, there is provided:
A double-ended piston is accommodated in a plurality of pairs of cylinder bores arranged before and after arranged around the rotary shaft, and the rotational motion of the swash plate supported by the rotary shaft is converted into the reciprocating motion of the double-headed piston. The swash plate compressor discharges the refrigerant gas in the cylinder bores into the discharge chambers before and after the rotary shaft. The rotary shaft is rotatably supported by a pair of conical roller bearings. The chambers are communicated with each other by a discharge passage, and at least a part of the refrigerant gas flow path between the discharge chamber and the discharge passage in the rotary shaft is provided between an outer ring and an inner ring sandwiching the rollers of the conical roller bearing.

[0007]

The radial load and the thrust load acting on the rotary shaft are both received via a pair of conical roller bearings. The refrigerant gas discharged from one of the front and rear cylinder bores into one discharge chamber joins the other discharge chamber via a discharge passage in the rotating shaft. At least a portion of the refrigerant gas entering the discharge passage in the rotation shaft from one discharge chamber passes between the outer ring and the inner ring of one conical roller bearing. At least a portion of the refrigerant gas flowing from the discharge passage in the rotation shaft to the other discharge chamber passes between the outer ring and the inner ring of the other conical roller bearing. Therefore, the pair of conical roller bearings is lubricated by the lubricating oil flowing together with the discharged refrigerant gas.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will now be described with reference to FIGS.
A description will be given based on FIG. As shown in FIG. 1, accommodation holes 1a and 2a are formed in the center of a pair of front and rear cylinder blocks 1 and 2 which are joined. Cylinder blocks 1, 2
The valve plates 3 and 4 are joined to end surfaces of the valve plates 3 and 4, and support holes 3 a and 4 a are provided in the valve plates 3 and 4. Annular positioning projections 3b, 4b are protruded from the peripheral edges of the support holes 3a, 4a, and the positioning projections 3b, 4b
Are fitted in the receiving holes 1a and 2a. Pins 5 and 6 are inserted through the valve plates 3 and 4 and the cylinder blocks 1 and 2, and the rotation of the valve plates 3 and 4 with respect to the cylinder blocks 1 and 2 is prevented by the pins 5 and 6.

Support holes 3a, 4a of valve plates 3, 4
, A rotating shaft 7 is rotatably supported via conical roller bearings 8 and 9. Outer ring 8a of conical roller bearings 8, 9
9a is slidably fitted and supported in the receiving holes 1a and 2a, and the inner races 8b and 9b are stepped portions 7a and 7
b and is fixed. Outer ring 8a, 9a and inner ring 8
The rollers 8c, 9c sandwiched between the rollers 8b, 9b are inclined with respect to the rotating shaft 7, and the orbits of the rollers 8c, 9c are on a conical surface.

A swash plate 10 is fixedly supported on the rotating shaft 7. An inlet 12 is formed in each of the cylinder blocks 1 and 2 forming the swash plate chamber 11, and the inlet 12 is connected to an externally drawn refrigerant gas line (not shown).

As shown in FIGS. 2 and 3, a plurality of cylinder bores 13, 1
3A, 14 and 14A are formed. As shown in FIG. 1, a pair of cylinder bores 13, 14, 13A, 1
4A (five pairs in this embodiment) has double-headed pistons 15, 1
5A is reciprocally accommodated. Double-headed piston 1
Hemispherical shoes 16, 17 are interposed between 5, 5A and the front and rear surfaces of the swash plate 10. Accordingly, the rotation of the swash plate 10 causes the double-headed pistons 15, 15A to move back and forth in the cylinder bores 13, 14, 13A, 14A.

A front housing 18 is joined to an end face of the cylinder block 1, and a rear housing 19 is also joined to an end face of the cylinder block 2. As shown in FIGS. 4 and 5, annular holding projections 18a, 19a are provided on the inner wall surfaces of the housings 18, 19, respectively.

An annular plate-shaped preload applying spring 20 is interposed between the pressing ridge 18a and the outer ring 8a of the conical roller bearing 8. The outer peripheral edge of the preload applying spring 20 is fitted into the holding ridge 18a. With this fitting configuration, the preload applying spring 20 is supported so as not to be displaced with respect to the front housing 18. The end surface of the outer ring 8a of the conical roller bearing 8 projects from the end surface of the wall forming the support hole 3a of the valve plate 3, and the inner peripheral edge of the preload applying spring 20 abuts the end surface of the outer ring 9a of the conical roller bearing 9. ing. The pressing ridge 19a is in contact with the end surface of the outer ring 9a of the conical roller bearing 9.

The orbits of the rollers 8c and 9c of the conical roller bearings 8 and 9 are on a conical surface, and the large diameter sides of the conical surfaces which are the orbits of the two rollers 8c and 9c are opposed to each other. The inner rings 8b and 9b of the conical roller bearings 8 and 9 are
a, 7b. Therefore, a thrust load on the rotating shaft 7 from the front housing 18 toward the rear housing 19 is received by the rear housing 19 through the conical roller bearing 9. Also, the rear housing 19
The thrust load on the rotating shaft 7 from the side toward the front housing 18 is received by the front housing 18 via the conical roller bearing 8 and the preload applying spring 20.

The cylinder block 1, the valve plate 3 and the front housing 18 are fastened and fixed by bolts 21. The cylinder block 2, the valve plate 4 and the rear housing 19 are fastened and fixed by bolts 22. The tightening of the bolt 21 causes the preload applying spring 20 to bend and deform, and this bending deformation applies a preload to the rotary shaft 7 via the conical roller bearing 8.

A discharge chamber 2 is provided in both housings 18 and 19.
3, 24 are formed. Double-headed piston 15, 15A
The compression chambers Pa and Pb defined in the cylinder bores 13, 14, 13A, and 14A are connected to the discharge chambers 23 and 24 via the discharge ports 3c and 4c on the valve plates 3 and 4, respectively. The discharge ports 3c and 4c are opened and closed by flapper valve type discharge valves 31 and 32, respectively. The opening of the discharge valves 31 and 32 is regulated by retainers 33 and 34. Discharge valve 3
The retainers 1 and 32 and the retainers 33 and 34 are fixed on the valve plates 3 and 4 by bolts 35 and 36. The discharge chamber 23 communicates with a not-shown external discharge refrigerant gas pipe via a discharge passage 25.

Reference numeral 26 denotes a discharge chamber 23 along the peripheral surface of the rotating shaft 7.
This is a lip seal that prevents refrigerant gas from leaking from the compressor to the outside. Rotary valves 27 and 28 are supported on the steps 7 a and 7 b on the rotating shaft 7. Rotary valve 2
Seal rings 39, 40 are provided between the rotary shaft 7,
Is interposed. The rotary valves 27 and 28 are housed in the housing holes 1a and 2a so as to be rotatable integrally with the rotating shaft 7. The refrigerant gas pressure discharged from the discharge chambers 23, 24 acts on one end of the rotary valves 27, 28, and the refrigerant gas pressure suctioned from the swash plate chamber 11 acts on the other end. That is,
The rotary valves 27 and 28 shut off the discharge pressure region and the suction pressure region.

In the rotary valves 27 and 28, suction passages 29 and 30 are formed. The inlets 29a, 30a of the suction passages 29, 30 open to the swash plate chamber 11, and the outlets 29b, 30b of the suction passages 29, 30 open on the peripheral surface.

As shown in FIG. 2, cylinder bores 13, 13 are provided on the inner peripheral surface of the accommodation hole 1a for accommodating the rotary valve 27.
The same number of suction ports 1b as A are arranged at equal angular positions. Suction port 1b and cylinder bores 13, 13
A is always in one-to-one communication with A, and each suction port 1b is connected to a circulating region of the outlet 29b of the suction passage 29.

Similarly, as shown in FIG. 3, a cylinder bore 1 is provided on the inner peripheral surface of the accommodation hole 2a for accommodating the rotary valve 28.
The same number of suction ports 2b as 4, 14A are arranged at equal angular intervals. Suction port 2b and cylinder bore 1
The suction ports 2b are always in communication with the suction ports 4 and 14A in a one-to-one correspondence, and each suction port 2b is connected to a circulation area of the outlet 30b of the suction passage 30.

In the state shown in FIGS. 1, 2 and 3, the double-headed piston 15A is at the top dead center position with respect to one cylinder bore 13A and at the bottom dead center position with respect to the other cylinder bore 14A. In such a piston arrangement state, the outlet 29b of the suction passage 29 is located immediately before connection to the suction port 1b of the cylinder bore 13A, and the outlet 3b of the suction passage 30
0b is immediately after connection to the suction port 2b of the cylinder bore 14A. That is, when the double-headed piston 15A enters the suction stroke from the top dead center position to the bottom dead center position with respect to the cylinder bore 13A, the suction passage 29 is connected to the cylinder bore 13A.
A communicates with the compression chamber Pa of A. This communication enables the swash plate chamber 11
The refrigerant gas in the cylinder bores 1 through the suction passage 29
It is sucked into the compression chamber Pa of 3A. On the other hand, double-headed piston 1
When 5A enters the discharge stroke from the bottom dead center position to the top dead center position with respect to the cylinder bore 14A, the suction passage 30
Is disconnected from the compression chamber Pb of the cylinder bore 14A. This communication cutoff causes the compression chamber P of the cylinder bore 14A.
b while the refrigerant gas in b pushes out the discharge valve 3 and discharge port 4
c to the discharge chamber 24.

Such suction and discharge of the refrigerant gas are similarly performed in the compression chambers P of the other cylinder bores 13 and 14. One end of the rotating shaft 7 projects outside from the front housing 18, and the other end projects from the valve plate 4 into the rear housing 19. A discharge passage 37 is formed in the axis of the rotating shaft 7. The discharge passage 37 opens in the rear housing 19. An outlet 38 is formed in a peripheral surface portion of the rotating shaft 7 surrounded by the discharge chamber 23 on the front housing 18 side.

Support hole 3 for accommodating conical roller bearings 8, 9
A plurality of openings 3d and 4d are formed in the wall forming a and 4a. The through-hole 3d is provided with an outer ring 8a of the conical roller bearing 8.
The gap between the inner ring 8b and the discharge chamber 23 is communicated.
The passage 4d communicates the gap between the outer ring 9a and the inner ring 9b of the conical roller bearing 9 with the discharge chamber 24. Therefore, the front and rear discharge chambers 23 and 24 are formed by the openings 3d and 4d and the outer races 8a and 9 respectively.
a and the inner rings 8b, 9b, the outlet 38, and the discharge passage 37 communicate with each other.

The discharged refrigerant gas discharged into the discharge chamber 24 passes through the passage 4d and the outer ring 9a and the inner ring 9b of the conical roller bearing 9
Flows into the gap between. The discharged refrigerant gas that has passed between the outer ring 9a and the inner ring 9b enters a discharge passage 37 in the rotating shaft 7. The discharged refrigerant gas flowing into the discharge passage 37 is supplied to the outlet 38
And passes through a gap between the outer ring 8a and the inner ring 8b of the conical roller bearing 8. The discharged refrigerant gas passing between the outer ring 8a and the inner ring 8b joins the discharge chamber 23 through the passage 3d, and is discharged from the discharge passage 25 to an external discharged refrigerant gas pipe.

The lubricating oil flows along with the movement of the refrigerant gas, and the conical roller bearings 8 and 9 serve as flow paths for the discharged refrigerant gas.
Is supplied between the outer rings 8a, 9a and the inner rings 8b, 9b. Therefore, the rolling contact portion between the inner and outer rings 8b, 9b, 8a, 9a and the roller 8c is lubricated, and flaking and fretting in the conical roller bearings 8, 9 do not occur. That is, the reliability of the conical roller bearings 8, 9 is ensured.

The conventional structure in which the discharge passage in the cylinder block is moved to the inside of the rotary shaft 7 eliminates the need for a space for the discharge passage in the cylinder block. Therefore, the whole compressor can be made compact.

Further, since both the radial load and the thrust load on the rotating shaft 7 are received via the conical roller bearings 8, 9, the number of bearing members for the rotating shaft 7 is reduced by half compared to the conventional case. Therefore, the assembling operation process is simplified.

In this embodiment, the rotary valves 27 and 28 are employed as suction valves. However, this configuration has the following advantages. In the case of a flapper valve type suction valve,
The lubricating oil increases the suction force between the suction valve and its close contact surface, and the opening start timing of the suction valve is delayed by the suction force. This delay causes the suction resistance due to the elastic resistance of the suction valve to reduce the volumetric efficiency. However, when the rotary valves 27 and 28 that are forcibly rotated are employed, there is no problem of the suction force due to the lubricating oil and the suction resistance due to the elastic resistance of the suction valve, and the pressure in the compression chambers P, Pa, and Pb is reduced.
If the suction pressure in the chamber is slightly lower, the refrigerant gas immediately flows into the compression chambers P, Pa, and Pb. Therefore, the rotary valve 2
In the case of employing 7, 28, the volume efficiency is greatly improved as compared with the case of employing a flapper valve type suction valve.

A conventional suction passage in a cylinder block is provided one by one between adjacent cylinder bores, and the presence of such a suction passage reduces the strength of the cylinder block. A discharge passage is also provided in the cylinder block. Therefore, the arrangement interval of the cylinder bores is increased to the extent that the strength of the cylinder block can be secured, and the arrangement interval of the cylinder blocks cannot be reduced as long as the suction passage and the discharge passage exist in the cylinder block.

The structure in which the refrigerant gas sucked from the swash plate chamber 11 is sucked into the compression chambers P, Pa, and Pb via the suction passages 29 and 30 in the rotary valves 27 and 28 is the same as that of the conventional swash plate type compressor. Eliminates the need for a plurality of suction passages. By eliminating the suction passage from the cylinder blocks 1 and 2, the cylinder bores 13, 13A, 14, 14A
Can be narrowed. Cylinder bore 13,
The reduction in the arrangement interval of the cylinder bores 13A, 14, 14A leads to the reduction in the arrangement radius of the cylinder bores 13, 13A, 14, 14A, and the reduction in the diameter of the entire cylinder blocks 1, 2 is achieved. Therefore, diameter reduction and weight reduction of the entire compressor are achieved.

The use of the rotary valves 27 and 28 eliminates the need for a suction chamber in the conventional front housing and rear housing. Therefore, the conical roller bearings 8 and 9 can be arranged in the front housing 18 and the rear housing 19 instead of the suction chamber. That is, there is no need to provide an extra space for the bearing member for adopting the rotary valves 27 and 28, and it does not hinder compactness of the compressor.

The refrigerant gas in the swash plate chamber 11 is supplied to the compression chambers P, P
When the pressure in a, Pb falls below the pressure in swash plate chamber 11, it is sucked into compression chambers P, Pa, Pb. Flow path resistance in the refrigerant gas flow path from the swash plate chamber 11 to the compression chambers P, Pa, Pb;
That is, if the suction resistance is high, the pressure loss increases, and the compression efficiency decreases. By employing the rotary valves 27 and 28, the length of the refrigerant gas passage from the swash plate chamber 11 to the compression chambers P, Pa and Pb is shortened, and the suction resistance is reduced as compared with the conventional case. Therefore, loss is reduced and compression efficiency is improved.

The present invention is, of course, not limited to the above embodiment, but can be applied to, for example, a swash plate compressor as shown in FIGS. As shown in FIG. 6, a pair of front and rear cylinder blocks 43 fastened and joined by bolts 42,
A rotary shaft 45 is rotatably supported on the rotary shaft 44 via conical roller bearings 46 and 47. Conical roller bearings 46, 4
7 is housed in the housing holes 43a and 44a. Outer rings 46a and 47a of the conical roller bearings 46 and 47
a and 44a so as to be slidable. The inner rings 46b, 47b sandwiching the rollers 46c, 47c together with the outer rings 46a, 47a are fixed to the rotating shaft 45.

A swash plate 48 is fixedly supported on the rotating shaft 45. The cylinder blocks 43 and 44 have inlets 49 and 5 respectively.
0 is formed, and an external suction refrigerant gas line (not shown) is connected to the introduction ports 49 and 50. Inlet 49,
50 communicates with the swash plate chamber 66.

As shown in FIG. 7, a plurality of cylinder bores 51, 52 are formed at equally spaced angular positions about the rotation shaft 45. As shown in FIG. 6, a double-headed piston 53 is accommodated in a pair of front and rear cylinder bores 51 and 52 in a reciprocating manner, and a hemispherical shoe is provided between the double-headed piston 53 and both front and rear surfaces of a swash plate 48. 16, 17 are interposed.

A front cover 54 is fastened to the end face of the cylinder block 43 by bolts 55. A rear cover 56 is also fastened to the end surface of the cylinder block 44 by bolts 57. An annular preload applying spring 82 is interposed between the front cover 54 and the outer ring 46a of the conical roller bearing 46. The front cover 54 contacts the outer peripheral edge of the preload applying spring 82, and the outer race 46 a contacts the inner peripheral edge of the preload applying spring 82. A rear cover 56 is in contact with the outer ring 47a of the conical roller bearing 47. The preload applying spring 82 is bent and deformed similarly to the first embodiment.

The discharge chambers 58, 5 are provided in the covers 54, 56.
9 are formed. The discharge chambers 58 and 59 are covered by a cover 54,
It is connected to cylinder bores 51 and 52 via discharge ports 54 a and 56 a on the top 56. The discharge chamber 58 is connected to the discharge passage 6
0 communicates with an externally discharged refrigerant gas pipe (not shown).

Reference numeral 61 denotes a discharge chamber 5 along the peripheral surface of the rotating shaft 45.
This is a lip seal for preventing refrigerant gas from leaking out of the compressor from the outside. A pair of suction chambers 6 are provided in the double-headed piston 53.
2, 63 are sectioned. The suction chambers 62 and 63 are connected to the swash plate chamber 6 through the inlets 64 and 65 on the double-headed piston 53.
6 and the refrigerant gas in the swash plate chamber 66 flows through the inlet 6.
It is possible to flow into the suction chambers 62 and 63 through the ports 4 and 65.

As shown in FIG. 8, a suction port 67 is provided through the front end face of the double-headed piston 53 on the front side, and a suction valve 68 is interposed on the suction port 67. The suction valve 68 is a valve seat 6 fitted and fixed to the end face of the head.
9 and a disk-shaped float valve 70 housed in a valve seat 69.
And a circlip-type retainer 71 for accommodating and holding the float valve 70 in the valve seat 69.
The valve seat 69 has a through hole 72 formed therein.
Is opened and closed by the float valve 70.

A suction port 73 also extends through the rear end face of the double-headed piston 53 on the rear side, and a suction valve 74 similar to the suction valve 68 is interposed on the suction port 73.
A discharge valve 75 is interposed on the discharge port 54a.
As shown in FIG. 9, the discharge valve 75 is
A valve seat 76 fitted into and fixed to the valve seat, a disc-shaped float valve 77 housed in the valve seat 76, and the float valve 77
And a retainer 78 for accommodating and holding therein. The valve seat 76, the float valve 77, and the retainer 78 have the same shape as the valve seat 69, the float valve 70, and the retainer 71 of the suction valve 68.

A discharge valve 79 similar to the discharge valve 75 is interposed also on the discharge port 56a. During the backward stroke of the double-headed piston 53 on the cylinder bore 51 side, the refrigerant gas in the suction chamber 62 pushes the float valve 70 back and is sucked into the compression chamber Pa between the double-headed piston 53 and the front cover 54. The opening of the float valve 70 is regulated by contacting the retainer 71. During the forward stroke of the double-headed piston 53 on the side of the cylinder bore 51, the refrigerant gas in the compression chamber Pa pushes the float valve 70 and is discharged to the discharge chamber 58. The opening of the float valve 77 is regulated by contacting the retainer 78.

The same suction and discharge are performed on the compression chamber Pb side between the double-ended piston 53 and the rear cover 56 via the suction valve 74 and the discharge valve 79. One end of the rotating shaft 45 projects outside from the front cover 54, and the other end projects into the discharge chamber 59 on the rear cover 56 side. A discharge passage 80 is formed in the axis of the rotating shaft 45.
The discharge passage 80 is open to the discharge chamber 59.

Rotary shaft 45 surrounded by discharge chamber 58
A discharge port 81 is formed at a portion of the discharge port 58, and the discharge chamber 58 and the discharge passage 80 communicate with each other through the discharge port 81.
Also in this embodiment, both the radial load and the thrust load on the rotating shaft 45 are received via the conical roller bearings 46 and 47. The rotating shaft 45 is provided with an inflow port 45a and an outflow port 45b. The inflow port 45a communicates the gap between the outer ring 47a and the inner ring 47b of the conical roller bearing 47 with the discharge passage 59. Outer ring 47a and inner ring 47
The gap between the first and second b is exposed to the discharge chamber 59. Therefore,
Part of the refrigerant gas discharged from the discharge chamber 59 directly flows into the discharge passage 80 from the opening of the discharge passage 80, and the remainder is discharged through the gap between the outer ring 45a and the inner ring 45b of the conical roller bearing 46 and the inlet 45a. It flows into the passage 80.

The outlet 45b communicates the gap between the outer ring 46a and the inner ring 46b of the conical roller bearing 46 with the discharge passage 80. Therefore, a part of the refrigerant gas discharged in the discharge passage 80 flows directly from the outlet 81 to the discharge chamber 58, and the rest passes through the outlet 45 b and the gap between the outer ring 46 a and the inner ring 46 b of the conical roller bearing 46. It flows out to the discharge chamber 58. The refrigerant gas discharged from the discharge chamber 58 is discharged to the external discharge refrigerant gas pipe via the discharge passage 60.

Therefore, the lubrication of the conical roller bearings 46 and 47 is lubricated by the rough lubrication flow accompanying the movement of the discharged refrigerant gas, and the reliability of the conical roller bearings 46 and 47 is ensured. In addition, the suction refrigerant gas in the swash plate housing chamber 66 passes through the suction chambers 62 and 63 in the double-headed piston 53, and the compression chambers Pa and Pb.
The structure in which the suction is carried out eliminates the need for a plurality of suction passages in the cylinder block in the conventional swash plate compressor. Further, the configuration in which the refrigerant gas discharged into the discharge chamber 59 is guided to the discharge passage 60 via the discharge passage 80 in the rotating shaft 45 eliminates the need for the discharge passage in the cylinder block in the conventional swash plate compressor. Accordingly, the arrangement radius of the cylinder bores 51 and 52 can be reduced, and the entire compressor can be reduced in diameter and weight.

In the present embodiment, the suction chambers provided before and after the cylinder block are replaced with the suction chambers 62 and 63 in the double-headed piston 53 in the present embodiment, and this arrangement change also contributes to downsizing of the compressor as a whole.

[0047]

As described above in detail, according to the present invention, the rotating shaft is rotatably supported by a pair of conical roller bearings, a discharge passage is provided in the rotating shaft, and the front and rear discharge chambers are connected by the discharge passage. Since at least a part of the refrigerant gas flow path between the discharge chamber and the discharge passage in the rotary shaft is provided between the outer ring and the inner ring sandwiching the rollers of the conical roller bearing, the number of bearing members of the rotary shaft is reduced. As a result, a compact compressor can be obtained by eliminating the conventional discharge passage in the cylinder block, and a conical roller bearing is formed by the lubricating oil flowing along with the discharged refrigerant gas passing through the discharge passage. Has an excellent effect of being able to sufficiently lubricate.

[Brief description of the drawings]

FIG. 1 is a side sectional view of an entire compressor showing an embodiment embodying the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is a sectional view taken along line CC of FIG. 1;

FIG. 5 is a sectional view taken along line DD of FIG. 1;

FIG. 6 is a side sectional view of the entire compressor showing another example.

FIG. 7 is a sectional view taken along line EE of FIG. 6;

FIG. 8 is an enlarged side sectional view of a main part.

[Explanation of symbols]

Reference numeral 7: rotating shaft, 8, 9: conical roller bearing, 8a, 9a: outer ring, 8b, 9b: inner ring, 10: swash plate, 23, 24: discharge chamber, 37: discharge passage.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F04B 27/08 F04B 39/00 103

Claims (1)

(57) [Claims] A double-headed piston is housed in a plurality of pairs of cylinder bores arranged before and after arranged around a rotary shaft, and the rotational motion of a swash plate supported by the rotary shaft is converted to the reciprocating motion of the double-headed piston. In the swash plate compressor that converts and discharges the refrigerant gas in the cylinder bore into the discharge chambers before and after the cylinder block, the rotation shaft is rotatably supported by a pair of conical roller bearings, and a discharge passage is provided in the rotation shaft. The front and rear discharge chambers communicate with each other through a discharge passage, and at least a part of the refrigerant gas flow path between the discharge chamber and the discharge passage in the rotary shaft is provided between the outer ring and the inner ring sandwiching the rollers of the conical roller bearing. Rotary shaft support structure in a plate compressor.