JP2993197B2 - Swash plate compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention converts the rotational motion of a swash plate on a rotating shaft into a reciprocating motion of a double-headed piston, and discharges refrigerant gas from a pair of compression chambers at the front and rear by the forward motion of the double-headed piston. The present invention relates to a swash plate type compressor.

[0002]

2. Description of the Related Art In a swash plate compressor of this type, refrigerant gas in a compression chamber is discharged to a discharge chamber by a forward movement of a double-headed piston, and refrigerant gas in a suction chamber is sucked into the compression chamber by a backward movement of a double-headed piston. You. 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.

[0003] There are one suction chamber before and after the cylinder,
It communicates with the swash plate housing chamber via a suction passage in the cylinder block. There is also 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. The external suction refrigerant gas line communicates with the swash plate storage chamber through the inlet, and the refrigerant gas is first introduced into the swash plate storage chamber by the suction action accompanying the reciprocating operation of the double-headed piston, and the refrigerant gas in the cylinder block is removed. The air is introduced into the compression chamber through the suction passage and the suction chamber. The refrigerant gas introduced into the compression chamber is discharged to the discharge chamber while being compressed along with the forward movement of the double-headed piston, and is discharged to the external discharge refrigerant gas pipe through the discharge passage in the cylinder block.

[0004]

The arrangement interval of the cylinder bores is increased to the 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, usually, the suction passages are provided one by one between a plurality of cylinder bores arranged at equal angular positions around the rotation shaft, and one common discharge passage is provided. The presence of the passage causes a reduction in the strength of the cylinder block. Therefore, it is difficult to reduce the arrangement radius of the cylinder bores, and it is difficult to make the compressor compact, as long as the configuration in which the suction passage and the discharge passage extend through the cylinder block is adopted.

[0005] It is an object of the present invention to provide a swash plate type compressor capable of making the whole compressor compact.

[0006]

According to the present invention, there is provided:
A pair of suction chambers are provided in the double-headed piston, and an inlet port for introducing refrigerant to the compressor communicates with the suction chamber through a swash plate housing chamber, and a suction port connecting the suction chamber and the compression chamber is connected to the double-headed piston. And a suction valve for opening and closing a suction port.

[0007]

The suction valve opens in accordance with the suction operation of the double-headed piston into one of the front and rear compression chambers, and the refrigerant gas in the suction chamber flows into the compression chamber via the suction port. Refrigerant gas discharged from one of the front and rear of the pair of front and rear compression chambers flows into a discharge passage in a rotating shaft in a rotating state. The discharge passage in the rotation shaft communicates with an external discharge refrigerant gas pipe, and the discharge refrigerant gas flowing into the discharge passage in the rotation shaft is discharged together with the refrigerant gas discharged from the other compression chamber. It is discharged to the pipeline.

The structure in which the refrigerant gas in the swash plate accommodating chamber is directly introduced into the suction chamber in the double-headed piston eliminates the need for the conventional suction passage in the cylinder block, and introduces the discharged refrigerant gas into the discharge passage in the rotating shaft. The configuration eliminates the need for a conventional discharge passage in the cylinder block. By omitting the suction passage and the discharge passage in the cylinder block, the arrangement radius of the cylinder bores can be reduced, and the entire compressor can be made compact.

If a discharge assisting rotary blade is interposed on the discharge passage in the rotary shaft, the rotary blade rotates integrally with the rotary shaft and transfers the refrigerant gas in the discharge passage to the external discharge refrigerant gas pipe side. Help sending out. Therefore, the pressure in the communication region between the discharge port and the discharge passage is reduced, and the refrigerant gas in the compression chamber can be discharged without overcompression.

Since the discharge passage in the rotating shaft communicates with the surrounding discharge pressure region, the discharged refrigerant gas may leak to the swash plate accommodating chamber along the peripheral surface of the rotating shaft. If a seal ring is interposed between the cylinder housing and the peripheral surface of the rotating shaft between the plate housing chamber, leakage of the discharged refrigerant gas along the peripheral surface of the rotating shaft is prevented.

The shoe interposed between the swash plate and the double-headed piston is supported so as not to be detachable and slidably in contact with the piston. By communicating with the introduction passage, the mist-like lubricating oil in the refrigerant gas is supplied from the lubricating oil introduction passage to between the shoe and the fitting recess. Lubrication between the shoe and the double-headed piston is favorably performed by this lubricating oil supply.

If a float valve is used as a suction valve that floats so as to open the suction port during a piston suction stroke and close the suction port during a discharge stroke, the float valve moves substantially in parallel to open and close the suction port. Therefore,
The passage cross-sectional area at the suction port can be increased as compared with the bending-deformed suction valve, and the suction resistance can be reduced.

If a float valve that floats so as to close the discharge port during the suction stroke of the piston and open the discharge port during the discharge stroke is used as the discharge valve, the float valve moves substantially in parallel to open and close the discharge port. Therefore,
The passage cross-sectional area at the discharge port can be made larger than that of the discharge valve that bends and deforms, and the discharge resistance can be reduced.

[0014]

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.
A rotary shaft 3 is rotatably supported via a pair of radial bearings 4 and 5 on a pair of front and rear cylinder blocks 1 and 2 which are tightened and joined by a swash plate 6. I have. Thrust bearings 8, 9 are interposed between the end faces of the cylinder blocks 1, 2 forming the swash plate housing chamber 7 and the swash plate 6. Cylinder blocks 1, 2
Have inlets 10 and 11 formed therein.
An external suction refrigerant gas line (not shown) is connected to 11.

As shown in FIGS. 2 to 7, a plurality of cylinder bores 12, 13 are provided at equal angular positions around the rotation shaft 3.
Are formed. As shown in FIG. 1, a double-headed piston 14 is accommodated in a pair of front and rear cylinder bores 12 and 13 so as to be able to reciprocate, and a hemispherical shoe is provided between the double-headed piston 14 and both front and rear surfaces of the swash plate 6. 15, 16 are interposed. Accordingly, the rotation of the swash plate 6 causes the double-headed piston 14 to move back and forth in the cylinder bores 12 and 13.

The shoes 15, 16 are fitted and supported in supporting recesses 59, 60 of the double-headed piston 14. Support recess 5
9 and 60 are provided with oil introduction passages 61 and 62, respectively.
It is penetrated so as to communicate with. Some of the spherical portions of the shoes 15 and 16 are formed in a plane, and gaps 63 and 64 between the planes and the support recesses 59 and 60 are always in communication with the oil introduction passages 61 and 62.

A front cover 17 is fastened to the end face of the cylinder block 1 by bolts 71, and a rear cover 18 is fastened to the end face of the cylinder block 2 by bolts 72. Both covers 1
Discharge gaps 19 and 20 are formed in 7 and 18, respectively.
The discharge gaps 19 and 20 are connected to the cylinder bores 12 and 13 via discharge ports 21 and 22 on the covers 17 and 18. The discharge gap 19 communicates with a not-shown external discharge refrigerant gas pipe via a discharge passage 23.

Reference numeral 24 denotes a discharge gap 1 along the peripheral surface of the rotating shaft 3.
9 is a lip seal for preventing refrigerant gas from leaking out of the compressor 9. A pair of suction chambers 2 are provided in the double-headed piston 14.
5, 26 are sectioned. The suction chambers 25 and 26 communicate with the swash plate housing chamber 7 through the inlets 27 and 28 on the double-headed piston 14, and the refrigerant gas in the swash plate housing chamber 7 flows through the inlets 27 and 28 to the suction chamber. 25, 26.

As shown in FIGS. 1, 6 and 7, a plurality of passages 49 extend through the swash plate 6 in the thickness direction of the swash plate 6. The passages 49 are arranged at predetermined radial positions around the rotation shaft 3, and the arrangement radial positions substantially correspond to the inlets 27 and 28. The passage 49 is provided for smoothly guiding the refrigerant gas in the swash plate accommodating chamber 7 divided by the swash plate 6 to the inlets 27 and 28.

A suction port 30 extends through the head end face 29 on the front side of the double-headed piston 14, and a suction valve 31 is interposed on the suction port 30. As shown in FIGS. 8 and 10, the suction valve 31 includes a valve seat 32 fitted and fixed to the head end surface 29, a disk-shaped float valve 33 housed in the valve seat 32, and a float valve 33. And a circlip type retainer 34 for holding and holding it in the seat 32. As shown in FIG. 9, a pair of communication ports 35 are formed in the valve seat 32, and the communication ports 35 are opened and closed by a float valve 33. A small opening 36 is formed at the center of the float valve 33, and the float valve 33 is
In a state in which 5 is closed, the fore 36 is closed by a bridge 37 between the two through holes 35.

Rear head end face 3 of double-headed piston 14
8 also has a suction port 39 penetrating therethrough.
Above 9, a suction valve 40 similar to suction valve 31 is interposed. A discharge valve 41 is interposed on the discharge port 21. As shown in FIG. 8, the discharge valve 41 includes a valve seat 42 fitted and fixed to the front cover 17, a disk-shaped float valve 43 housed in the valve seat 42, and a float valve 43 inside the valve seat 42. And a retainer 44 for accommodating and holding it. Valve seat 42, float valve 43, and retainer 44
Have the same shape as the valve seat 32, the float valve 33 and the retainer 34 of the suction valve 31.

A discharge valve 45 similar to the discharge valve 41 is interposed on the discharge port 22. During the backward stroke of the double-headed piston 14 on the side of the head end face 29, the refrigerant gas in the suction chamber 25 pushes the float valve 33 back and is sucked into the compression chamber 46 between the head end face 29 and the front cover 17. The opening of the float valve 33 is regulated by contacting the retainer 34.
During the forward stroke of the double-headed piston 14 on the side of the head end surface 29, the refrigerant gas in the compression chamber 46 pushes the float valve 43 and is discharged to the discharge gap 19. The opening of the float valve 43 is regulated by contacting the retainer 34.

The other head end surface 38 of the double-headed piston 14
The same suction and discharge are performed through the suction valve 40 and the discharge valve 45 on the side of the compression chamber 48 between the rear and the rear cover 18.

One end of the rotating shaft 3 projects outside from the front cover 17, and the other end projects into the discharge gap 20 on the rear cover 18 side. A discharge passage 50 is formed in the axis of the rotating shaft 3. The discharge passage 50 is provided for the discharge gap 20.
It is open to.

An outlet 51 is formed in the portion of the rotary shaft 3 surrounded by the discharge gap 19 on the front cover 17 side, and the discharge gap 19 and the discharge passage 50 are connected to the outlet 51.
Is communicated by

The radial bearings 4, 5 are accommodated in annular accommodation gaps 52, 53, and oil supply ports 54, 5 are provided in a portion of the rotating shaft 3 surrounded by the accommodation gaps 52, 53.
5 are formed. Seal members 56 and 57 are accommodated in the accommodation gaps 52 and 53, respectively.

A rotary blade 58 is fitted and fixed in the discharge passage 50. As shown in FIGS. 1, 2 and 3, the rotating shaft 3 rotates in the direction of arrow α, and the direction of air blowing of the rotary wings 58 accompanying this rotation is in the direction of arrow β in FIG.

The refrigerant gas in the external suction refrigerant gas pipe is introduced into the swash plate storage chamber 7, and the refrigerant gas in the swash plate storage chamber 7 is supplied to the inlet 2.
The air enters the suction chambers 25, 26 via 7, 28. Inhalation chamber 2
The refrigerant gases 5 and 26 push back the float valves 33 and 43 by the reciprocation of the double-headed piston 14 while the suction ports 30 and
From 39, it is sucked into the compression chambers 46,48. Compression chamber 46,
The refrigerant gas 48 is discharged from the discharge ports 21 and 22 to the discharge gaps 19 and 20 while pushing down the float valve 43 by the forward movement of the double-headed piston 14. Refrigerant gas discharged into the discharge gap 20 flows through the opening 65 of the discharge passage 50 through the discharge passage 5.
Enter within 0.

The discharged refrigerant gas flowing into the discharge passage 50 from the discharge gap 20 is supplied to the outlet 5
1 to the discharge gap 19. The refrigerant gas discharged from the discharge gap 19 is discharged to the external discharge refrigerant gas pipe via the discharge passage 23.

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 refrigerant gas sucked in the swash plate accommodating chamber 7 passes through the suction chambers 25 and 26 in the double-headed piston 14 and the compression chambers 46 and
The configuration in which the intake air is sucked into the compressor 8 eliminates the need for a plurality of intake passages in the cylinder block in the conventional swash plate compressor. Further, the configuration in which the discharge refrigerant gas discharged to the discharge gap 20 is guided to the discharge passage 23 via the discharge passage 50 in the rotating shaft 3 eliminates the need for the discharge passage in the cylinder block in the conventional swash plate type compressor. By eliminating the suction passage and the discharge passage from the cylinder blocks 1 and 2, the cylinder bores 12 and 1 are removed.
3 can be narrowed. Cylinder bore 1
The reduction in the arrangement interval between the cylinder bores 2 and 13 leads to the reduction in the arrangement radius of the cylinder bores 12 and 13, and the reduction in the diameter of the entire cylinder blocks 1 and 2 is achieved. Therefore, diameter reduction and weight reduction of the entire compressor are achieved.

In the present invention, the suction chambers provided before and after the cylinder block are replaced with the suction chambers 25 and 26 in the double-headed piston 14 in the present invention, and this arrangement change also contributes to the compactness of the entire compressor.

The refrigerant gas in the compression chambers 46 and 48 is supplied to the compression chamber 4
When the pressure of 6,48 exceeds the pressure of the discharge gaps 19,20, discharge is performed. Since the discharge gap 19 is close to the discharge passage 50, there is no pressure pool more than necessary.
The discharge resistance between them determines the pressure state of the discharge gap 20 because the distance between the discharge gap and the outlet 51 is large. Therefore, in order to prevent the discharge gap 20 from becoming a pressure pool more than necessary, it is optimal to generate a suction effect at the opening 65 of the discharge passage 50. In order to generate such a suction action, the refrigerant gas may be forcibly pumped against the discharge resistance in the discharge passage region from the discharge gap 20 to the outlet 51.
In this embodiment, the rotating blades 58 pump the refrigerant gas in the discharge passage 50 toward the outlet 51.

The rotational resistance of the rotary blade 58 that rotates integrally with the rotary shaft 3 is small, and the pressure in the discharge gap 20 can be reduced without causing power loss. Such pressure reduction in the discharge gap 20 causes the compression chamber 48
Is discharged to the discharge gap 20 without becoming overcompressed. Accordingly, discharge pulsation and power loss due to overcompression in the compression chamber 48 are also suppressed. As the rotation speed of the compressor increases, the circulation amount of the refrigerant gas increases, and the overcompression state and discharge pulsation increase in proportion to the rotation speed. However, the compression chamber 4
8, the effect of suppressing power loss and suppressing discharge pulsation at high speed is high.

The refrigerant gas in the suction chambers 25 and 26 is supplied to the compression chamber 4
When the pressure of the suction chambers 6 and 48 falls below the pressure of the suction chambers 25 and 26, the pressure is sucked into the compression chambers 46 and 48. The flow path resistance in the refrigerant gas flow path from the swash plate accommodating chamber 7 to the compression chambers 46, 48, that is, the suction resistance determines the pressure state of the suction chambers 25, 26. If the suction resistance is high, the suction pulsation increases, and the power loss also increases.

The suction resistance in the refrigerant gas flow path from the swash plate accommodating chamber 7 to the compression chambers 46, 48 is at the suction ports 30, 39 in the space-limited portions on the head end surfaces 29, 38 of the double-headed piston 14. Depends exclusively on inhalation resistance. The suction resistance at the suction ports 30, 39 is reduced by increasing the cross-sectional area of the suction valves 31, 40. The float valves 33 constituting the suction valves 31 and 40 move substantially in parallel between the valve seat 32 and the retainer 34. As shown in FIG. 8, assuming that the parallel movement distance of the float valve 33 is γ, the outer peripheral length of the float valve 33 is δ, and the inner peripheral length of the float valve 33 is ε, the passage cross-sectional area of the suction valves 31 and 40 is γ (δ + ε ).

The suction valve in the conventional compressor is a cantilever-supported valve plate, and the valve plate is bent to open the suction port. The passage cross-sectional area of such a suction valve is substantially half that of the suction valves 31 and 40 of this embodiment when the amount of deflection displacement of the valve plate is the same as the parallel movement distance of the float valve 33. Increasing the amount of deflection displacement of the valve body increases the passage cross-sectional area. However, if such a valve plate is used in a space-limited portion on the head end surfaces 29 and 38, the double-headed piston 14
Inevitably grow. Even if the displacement distance of the float valve 33 is less than the amount of deflection of the valve plate of the conventional suction valve, the suction valve 3
The passage cross-sectional area of 1, 40 is larger than that of the conventional suction valve, and the suction resistance can be suppressed without causing the double-ended piston 14 to increase.

Discharge valves 41 and 4 having a built-in float valve 43
5 also increases the passage cross-sectional area at the discharge ports 21 and 22, that is, reduces the discharge resistance while suppressing the increase in the thickness of the covers 17 and 18, and contributes to the suppression of discharge pulsation and power loss together with the rotary blade 58.

Mist lubricating oil is mixed in the refrigerant gas, and this lubricating oil adheres to the peripheral wall of the discharge passage 50. Part of the lubricating oil adhering to the peripheral wall of the discharge passage 50 enters the housing gaps 52 and 53 from the oil supply ports 54 and 55 due to centrifugal force caused by the rotation of the rotary shaft 3, and the radial bearings 4 and 5
Lubrication is performed well.

The mist-like lubricating oil in the refrigerant gas adheres to the walls of the suction chambers 25 and 26 in the double-headed piston 14. The lubricating oil adhering to the wall surfaces of the suction chambers 25 and 26
Of the oil introducing passages 61 and 62 through the gap 6
Go into 3,64. Therefore, the sliding portions between the support recesses 59 and 60 and the spherical portions of the shoes 15 and 16 are lubricated by the lubricating oil supplied from the oil introduction passages 61 and 62, and the shoes 15 and 16 and the support recesses 59 and 60 are lubricated. Is prevented from burning in the sliding contact portion between the two.

The gaps 63 and 64 serve as oil reservoirs.
Even without the gaps 63 and 64, the sliding portions between the shoes 15 and 16 and the support recesses 59 and 60 are well lubricated.
The accommodating gap 52 extends along the outer peripheral surface of the rotating shaft 3 and the discharge gap 19.
The accommodating gap 53 is connected to the discharge gap 20 along the outer peripheral surface of the rotating shaft 3. That is, the oil supply port 5
The discharge gaps 19 and 20 are discharge pressure regions even without the discharge gaps 4 and 55, and there is a possibility that the discharged refrigerant gas leaks along the outer peripheral surface of the rotating shaft 3 into the swash plate housing chamber 7 that becomes the suction pressure region. However, the gap between the swash plate housing chamber 7 and the housing gaps 52, 53 is sealed by seal members 56, 57, and the seal members 56, 57 are sealed by the pressure of the discharged refrigerant gas. 53 closely adheres to the peripheral surface. Therefore, the discharged refrigerant gas does not leak to the swash plate housing chamber 7 along the outer peripheral surface of the rotating shaft 3.

The present invention is, of course, not limited to the above embodiment, but may be, for example, the embodiment shown in FIG. A discharge port 66 is provided through a wall of the rear cover 18 facing the opening 65 of the rotating shaft 3 in this embodiment, and an external discharge refrigerant gas pipe (not shown) is connected to the discharge port 66.

Rotary shaft 3 surrounded by discharge gap 19
Is formed with an inlet 67, and the discharge gap 19 is formed.
And the discharge passage 50 are communicated with each other by an inlet 67. The rotating blade 68 is fitted and fixed in the discharge passage 50. The rotating shaft 3 rotates in the direction of the arrow α, and the direction of air blowing of the rotary blade 68 accompanying this rotation is in the direction of the arrow の in FIG.

The refrigerant gas in the compression chambers 46, 48 is discharged from the discharge ports 21, 22 to the discharge gaps 19, 20 by the forward movement of the double-headed piston 14, and the refrigerant gas discharged to the discharge gap 19 flows from the inlet 67 to the discharge passage. Go into 50. The refrigerant gas discharged from the discharge port 22 to the discharge gap 20 is directly discharged from the discharge port 66.

Since the distance between the discharge gap 19 and the discharge port 66 is large, the discharge resistance between them affects the pressure state of the discharge gap 19. In order to prevent the discharge gaps 19 and 20 from becoming a pressure pool more than necessary, it is optimal to generate a suction action at the inlet 67 and to generate a suction action from the discharge gap 20 to the discharge port 66. In order to generate such a suction action, the refrigerant gas may be forcibly pumped against the discharge resistance in the discharge passage region from the discharge gap 19 to the discharge port 66. In this embodiment, the rotating blades 58 pump the refrigerant gas in the discharge passage 50 toward the outlet 66.

[0046]

As described above in detail, according to the present invention, the refrigerant gas in the swash plate accommodating chamber is introduced into the compression chamber through the suction chamber in the double-headed piston, and is discharged from one of the front and rear compression chambers. Refrigerant gas is discharged to the outside of the compressor via the discharge passage in the rotating shaft, so that the expansion of the cylinder block due to the presence of the suction passage and the discharge passage in the cylinder block in the conventional swash plate type compressor. In addition to eliminating the diameter, the space for the suction chambers in both the front and rear housings is no longer required, thereby providing an excellent effect that the entire compressor can be made compact and lightweight.

[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 sectional view taken along line EE of FIG. 1;

FIG. 7 is a sectional view taken along line FF of FIG. 1;

FIG. 8 is an enlarged side sectional view of a discharge valve and a float valve.

FIG. 9 is a sectional view taken along line GG of FIG. 8;

FIG. 10 is an exploded perspective view of a swash plate, a double-headed piston, and a suction valve.

FIG. 11 is a side sectional view of the entire compressor showing another example.

[Explanation of symbols]

3 ... rotating shaft, 14 ... double-headed piston, 19, 20 ... discharge gap, 21, 22 ... discharge port, 25, 26 ... suction chamber, 2
9, 38: head end face, 30, 39: suction port, 3
1, 40: suction valve, 33, 43: float valve, 41, 4
5 ... discharge valve, 46, 48 ... compression chamber, 50 ... discharge passage, 5
6, 57 ... seal member, 58, 68 ... rotating blade, 61, 6
2. Oil introduction passage.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoya Yokomachi 2-1-1 Toyota-cho, Kariya-shi, Aichi, Japan Inside Toyota Industries Corporation (58) Field surveyed (Int. Cl. ⁶ , DB name) F04B 27 / 08

Claims (6)

(57) [Claims] 1. A rotary motion of a swash plate supported by a rotary shaft is converted into a reciprocating motion of a double-headed piston in a cylinder block via a shoe, and a pair of front and rear compression chambers in a forward and backward motion of the double-headed piston. In a swash plate type compressor that discharges refrigerant gas from a discharge port while pushing out a discharge valve, a discharge passage is provided in the rotation shaft, and the discharge port communicates with a discharge passage in the rotation shaft. A pair of suction chambers are provided, and an inlet port for introducing refrigerant to the compressor communicates with the suction chambers through a swash plate housing chamber, and a suction port connecting the suction chamber and the compression chamber has a double-headed piston head. A swash plate type compressor with a suction valve that penetrates the end face and opens and closes the suction port. 2. The swash plate type compressor according to claim 1, wherein a discharge impeller is provided on a discharge passage in said rotary shaft. 3. The swash plate compressor according to claim 1, wherein the discharge valve is a float valve that closes the discharge port during a suction stroke of a double-headed piston and floats so as to open the discharge port during a discharge stroke. 4. The swash plate compressor according to claim 1, wherein the suction valve is a float valve that opens so as to close the suction port during a suction stroke of the double-headed piston and closes the suction port during a discharge stroke. 5. The shoe is fitted and supported on a double-headed piston so as to be inseparable and slidable, and a lubricating oil introduction passage penetrates a fitting recess for supporting the shoe so as to communicate with the suction chamber. The swash plate type compressor according to claim 1 provided. 6. A rotary shaft is supported by the cylinder block, and between the rotary shaft and the cylinder block, leakage of refrigerant gas from a discharge pressure region to a swash plate accommodating chamber along a peripheral surface of the rotary shaft is prevented. The swash plate type compressor according to claim 1, further comprising a seal ring interposed therebetween.