JP4148857B2 - Piston compressor - Google Patents

Description

  The present invention relates to a cylindrical cylinder block in which a plurality of cylinder bores are formed at intervals in the circumferential direction, a bottomed cylindrical first housing that forms a crank chamber on one end face side of the cylinder block, and a cylinder A second housing with a bottom that forms a suction chamber and a discharge chamber on the other end surface side of the block, a main shaft extending in parallel with the cylinder bore in the crank chamber, and inserted into the cylinder bore and driven by the rotation of the main shaft The second housing relates to a piston-type compressor having an annular partition that is concentrically arranged with the cylinder block and divides the suction chamber and the discharge chamber. .

A cylindrical cylinder block in which a plurality of cylinder bores are formed spaced apart from each other in the circumferential direction, a bottomed cylindrical first housing that forms a crank chamber on one end face side of the cylinder block, and the other cylinder block A cylindrical bottomed second housing that forms a suction chamber and a discharge chamber on the end surface side, a main shaft that extends in parallel with the cylinder bore in the crank chamber, and a reciprocating motion in the cylinder bore that is inserted into the cylinder bore and driven by the rotation of the main shaft A piston compressor having an annular partition that is concentrically arranged with the cylinder block and that partitions the suction chamber and the discharge chamber, and is provided from the crank chamber side. A piston type compressor in which a cylinder block is fixed to a second housing by a plurality of bolts screwed to an annular partition wall of a second housing is disclosed in Patent Document Which is incorporated herein by reference.
In the piston compressor of Patent Document 1, by tightening the bolt, the end face of the annular partition wall comes into pressure contact with the valve plate disposed between the cylinder block and the second housing, and the discharge chamber is connected to the suction chamber. Leakage of high pressure gas is prevented.
JP 2001-99058 A

In order to reliably prevent high-pressure gas from leaking from the discharge chamber to the suction chamber, it is necessary to uniformly distribute the surface pressure of the contact portion between the valve plate and the annular partition wall end surface. In the piston compressor of Patent Document 1, in order to make the circumferential distribution of the surface pressure uniform, it is necessary to precisely manage the fastening force of a plurality of bolts arranged at intervals in the circumferential direction. There is a problem that the cost of assembling the compressor is increased.
In addition, the annular partition is locally bulged radially inward and outward at each bolt threaded portion, and an annular suction chamber or discharge chamber formed radially outward of the annular partition is at each bolt threaded portion. Since the width is locally narrow, there is a problem in that the flow resistance of the annular suction chamber or discharge chamber increases and the performance of the compressor is reduced.
Further, the annular partition wall bulges locally inward and outward in each bolt threaded portion, and an annular suction chamber or discharge chamber formed radially outward of the annular partition wall is in each bolt threaded portion. A suction port formed in the surrounding wall of the second housing, and a cylinder bore communicating with the suction port via an annular suction chamber formed radially outward of the annular partition; The pressure loss between the cylinder bores differs or the discharge port formed in the surrounding wall of the second housing and the annular discharge chamber formed radially outward of the annular partition. The pressure loss between the cylinder bores communicating with the discharge port differs for each cylinder bore, and there is a problem in that the performance of the compressor is reduced and noise is generated.

The present invention has been made in view of the above problems, and has a cylindrical cylinder block in which a plurality of cylinder bores are formed at intervals in the circumferential direction, and a crank chamber is formed on one end surface side of the cylinder block. A bottom cylindrical first housing, a bottomed cylindrical second housing forming a suction chamber and a discharge chamber on the other end face side of the cylinder block, a main shaft extending in parallel with the cylinder bore in the crank chamber, and a cylinder bore And a plurality of pistons that are reciprocated in the cylinder bore following the rotation of the main shaft, and the second housing is disposed concentrically with the cylinder block and defines an annular partition that separates the suction chamber and the discharge chamber A piston type compressor in which a cylinder block is fixed to the second housing by a bolt that is screwed into the second housing from the crank chamber side. Lower the assembly cost, and to provide a high performance and low noise piston compressor.

In order to solve the above problems, in the present invention, a cylindrical cylinder block in which a plurality of cylinder bores are formed spaced apart from each other in the circumferential direction, and a bottomed chamber that forms a rank chamber on one end face side of the cylinder block A cylindrical first housing, a bottomed cylindrical second housing forming a suction chamber and a discharge chamber on the other end face side of the cylinder block, a main shaft extending parallel to the cylinder bore in the crank chamber, and a cylinder bore A plurality of pistons inserted and reciprocated in the cylinder bore following the rotation of the main shaft, and the second housing is arranged in a concentric manner with the cylinder block and defines an annular first A partition wall and an annular second partition wall disposed radially inward of the first partition wall and concentrically with the first partition wall; a female thread is formed on an inner peripheral surface of the second partition wall; To the second Provided is a piston type compressor in which a cylinder block is fixed to a second housing by a bolt screwed into a female screw of a second partition wall of the housing, and an internal space of the second partition wall communicates with a crank chamber. To do.

In the piston compressor according to the present invention, by tightening the bolt, the end face of the annular first partition wall comes into pressure contact with the valve plate disposed between the cylinder block and the second housing, and suction is performed from the discharge chamber. Leakage of high pressure gas to the chamber is prevented. Since the annular second partition wall into which the bolt is screwed is arranged concentrically with the annular first partition wall, the contact between the end surface of the first partition wall generated by tightening the bolt and the valve plate is avoided. The contact surface pressure is uniformly distributed in the circumferential direction. As a result, leakage of high-pressure gas from the discharge chamber to the suction chamber is effectively prevented.
Since it is not necessary to precisely manage the fastening force of the plurality of bolts, the assembly cost of the piston compressor according to the present invention is low. Since the cylinder block is fixed to the second housing using a single bolt, the number of parts is small.
Since the bolt is not screwed into the annular first partition, the first partition does not bulge locally inward and outward in the radial direction, and the annular suction chamber or discharge formed radially outward of the first partition. The room does not narrow locally. Therefore, the flow resistance of the annular suction chamber formed radially outward of the first partition or the annular discharge chamber formed radially outward of the first partition is small. Therefore, the piston type compressor according to the present invention has high performance.
Since the bolt is not screwed into the annular first partition, the first partition does not bulge locally inward and outward in the radial direction, and the annular suction chamber or discharge formed radially outward of the first partition. The room does not narrow locally. Accordingly, the pressure loss between the suction port formed in the surrounding wall of the second housing and the cylinder bore communicating with the suction port via the annular suction chamber formed radially outward of the first partition wall, The difference between the cylinder bores is small, or between the discharge port formed in the surrounding wall of the second housing and the cylinder bore communicating with the discharge port via an annular discharge chamber formed radially outward of the first partition wall The difference in pressure loss between cylinder bores is small. Therefore, the piston type compressor according to the present invention has high performance and low noise.
Since the internal space of the second partition wall communicates with the crank chamber, one end of the gas path is connected to the second chamber when forming a gas path that connects the crank chamber, the suction chamber, and the discharge chamber for discharge capacity control. By communicating with the internal space of the partition wall, the path length of the path can be shortened, and the work cost of the path can be reduced.

In a preferred aspect of the present invention, a circular recess having an open end on the crank chamber side is formed in the head of the bolt, and one end of the main shaft enters the circular recess, and is supported by the head via a bearing. It is rotatably supported.
In a preferred embodiment of the present invention, the bolt is hollow.
In a preferred embodiment of the present invention, the bolt is made of steel and the cylinder block is made of a light alloy.
By using the head portion of the bolt that fixes the cylinder block to the second housing as the main shaft support member, the compressor can be reduced in size.
If the internal space is formed by hollowing the bolts that fix the cylinder block to the second housing, the space can be effectively used as a space for housing a member such as a filter, and the compressor can be downsized.
When the bolt is made of steel, the head of the bolt or the entire bolt can be thinned to reduce the weight of the bolt and thus the compressor. By making the bolt that supports the main shaft through the bearing the same material as the steel main shaft, changes in the radial gap between the main shaft and the bolt head at the bearing portion due to temperature change are prevented, The life of the bearing can be extended. By making the cylinder block made of a light alloy, the weight of the compressor can be reduced.

In a preferred aspect of the present invention, the suction chamber is formed radially outward of the first partition, and the discharge chamber is formed radially inward of the first partition.
In a preferred aspect of the present invention, the suction chamber is formed radially inward of the first partition, and the discharge chamber is formed radially outward of the first partition.
The suction chamber may be formed radially outward of the first partition and the discharge chamber may be formed radially inward of the first partition, or the suction chamber may be formed radially inward of the first partition, The discharge chamber may be formed radially outward of the first partition.

In a preferred embodiment of the present invention, the piston is a single-headed piston that engages a swash plate that is supported by the main shaft so as to be synchronously rotatable.
In a preferred aspect of the present invention, the piston is engaged with a swash plate supported by a main shaft so as to be synchronously rotatable, and an inclination angle of the swash plate with respect to the main shaft is variable, and connects the internal space of the second partition wall and the suction chamber. A first throttling device is disposed in the middle of the gas path, and a second throttling device is disposed in the middle of the gas path that connects the internal space of the second partition wall and the discharge chamber. The opening degree of the second expansion device is variable.
In a preferred aspect of the present invention, the first diaphragm device or the second diaphragm device is a spiral space formed between a female screw formed on the inner peripheral surface of the second partition wall and a male screw formed on the bolt. It is.
The piston type compressor according to the present invention is embodied as a swash plate type compressor having a single-headed piston that directly engages the swash plate, and a swing type compressor having a single-headed piston that engages the swash plate via the swing plate. Suitable for doing.
When the piston type compressor according to the present invention is embodied as a variable capacity swash plate type compressor or a swing type compressor, the internal space of the second partition wall, the suction chamber, and the discharge chamber are connected by a gas path, It is desirable to shorten the gas path length. By arranging a throttle device in the middle of both gas paths and making the opening of at least one throttle device variable, the compressor can be made variable.
If the spiral space formed between the internal thread formed on the inner peripheral surface of the second partition and the external thread formed on the bolt that fixes the cylinder block to the second housing is used as one of the throttle devices This eliminates the need for a separate diaphragm device, reduces the number of parts, and reduces the manufacturing cost of the compressor.

In the preferable aspect of this invention, the pressure of the discharge gas of a compressor is a supercritical pressure.
In a preferred embodiment of the present invention, the discharge gas of the compressor is carbon dioxide.
Since the piston compressor according to the present invention can effectively prevent leakage of high-pressure gas from the discharge chamber to the suction chamber, the pressure of the discharge gas of the compressor becomes supercritical pressure. Further, the compressor may be embodied as a compressor used for a compressor in which the pressure of the discharge gas becomes an ultra-high pressure, for example, a cooling device in which the high-pressure side pressure of the closed circuit constituting the cooling device becomes a supercritical pressure of carbon dioxide as a refrigerant. good.

In the piston compressor according to the present invention, by tightening the bolt, the end face of the annular first partition wall comes into pressure contact with the valve plate disposed between the cylinder block and the second housing, and suction is performed from the discharge chamber. Leakage of high pressure gas to the chamber is prevented. Since the annular second partition wall into which the bolt is screwed is arranged concentrically with the annular first partition wall, the contact between the end surface of the first partition wall generated by tightening the bolt and the valve plate is avoided. The contact surface pressure is uniformly distributed in the circumferential direction. As a result, leakage of high-pressure gas from the discharge chamber to the suction chamber is effectively prevented.
Since it is not necessary to precisely manage the fastening force of the plurality of bolts, the assembly cost of the piston compressor according to the present invention is low. Since the cylinder block is fixed to the second housing using a single bolt, the number of parts is small.
Since the bolt is not screwed into the annular first partition, the first partition does not bulge locally inward and outward in the radial direction, and the annular suction chamber or discharge formed radially outward of the first partition. The room does not narrow locally. Therefore, the flow resistance of the annular suction chamber formed radially outward of the first partition or the annular discharge chamber formed radially outward of the first partition is small. Therefore, the piston type compressor according to the present invention has high performance.
Since the bolt is not screwed into the annular first partition, the first partition does not bulge locally inward and outward in the radial direction, and the annular suction chamber or discharge formed radially outward of the first partition. The room does not narrow locally. Accordingly, the pressure loss between the suction port formed in the surrounding wall of the second housing and the cylinder bore communicating with the suction port via the annular suction chamber formed radially outward of the first partition wall, The difference between the cylinder bores is small, or between the discharge port formed in the surrounding wall of the second housing and the cylinder bore communicating with the discharge port via an annular discharge chamber formed radially outward of the first partition wall The difference in pressure loss between cylinder bores is small. Therefore, the piston type compressor according to the present invention has high performance and low noise.
Since the internal space of the second partition wall communicates with the crank chamber, one end of the gas path is connected to the second chamber when forming a gas path that connects the crank chamber, the suction chamber, and the discharge chamber for discharge capacity control. By communicating with the internal space of the partition wall, the route length of the route can be shortened, and the work cost of the route can be reduced.

An embodiment in which the present invention is applied to a variable capacity swash plate compressor will be described with reference to FIG.

The swash plate compressor 1 includes a bottomed cylindrical front housing 10 and a bottomed cylindrical rear housing 11 arranged concentrically with the front housing 10. The front housing 10 and the rear housing 11 are coupled to each other by a plurality of bolts 13 that are inserted into the peripheral wall of the rear housing 11 and screwed to the side wall of the front housing 10 with the gasket 12 held between the open end surfaces. .
The rear housing 11 has a first annular partition 11a and a second annular partition 11b disposed radially inward of the first annular partition 11a. The first annular partition 11 a and the second annular partition 11 ba are disposed concentrically with the outer peripheral wall of the rear housing 11. An annular suction chamber 14 is formed between the outer peripheral wall of the rear housing 11 and the first annular partition wall 11a, and an annular discharge chamber 15 between the first annular partition wall 11a and the second annular partition wall 11b. Is formed. The suction chamber 14 communicates with a suction port (not shown) formed on the outer peripheral wall of the rear housing 11, and the discharge chamber 15 communicates with a discharge port 16 formed on the bottom wall of the rear housing 11. An internal thread 11b 'is formed on the inner peripheral surface of the second annular partition wall 11b. A cylindrical space 11b ″ is formed inside the second annular partition wall 11b.
The front housing 10 and the rear housing 11 are formed of an aluminum alloy.

A cylindrical cylinder block 17 is fitted near the open end of the front housing 10. The cylinder block 17 is disposed concentrically with the front housing 10 and the rear housing 11. A plurality of cylinder bores 17a are formed in the cylinder block 17 at intervals in the circumferential direction. A center bore 17 b is formed at the radial center of the cylinder block 17. The rear housing side end of the center bore 17b is formed with a smaller diameter than the other parts. The cylinder block 17 is made of an aluminum alloy.
The cylinder block 17 has a head portion 18a that abuts against an end of the large diameter portion of the center bore 17b, and a male screw 18b 'formed on the main body 18b. It is fixed to the rear housing 11 by means of a steel bolt 18 that is screwed onto the rear housing 11. The cylinder block 17 and the rear housing 11 sandwich a valve plate 19 and a reed valve structure suction valve and discharge valve. A suction hole 19 a that allows the cylinder bore 17 a and the suction chamber 14 to communicate with each other, and a discharge hole 19 b that allows the cylinder bore 17 a and the discharge chamber 15 to communicate with each other are formed in the valve plate 19.
The bolt 18 is formed as a hollow body having a through hole 18c extending in the longitudinal direction. A portion of the through hole 18c that extends in the head portion 18a is enlarged in diameter to form a circular recess 18d in which a crank chamber side end, which will be described later, is opened.

A crank chamber 20 is formed in the front housing 10. A steel main shaft 21 extends coaxially with the front housing 10 in the crank chamber 20. One end of the main shaft 21 is supported by the front housing 10 through the thrust bearing 22 and the radial bearing 23 in the direction of the central axis, and is supported so as to be rotatable about the central axis. 10 extends outside and engages with the electromagnetic clutch 24. The other end of the main shaft 21 enters the center bore 17b of the cylinder block and the through hole 18c of the bolt 18, and the head of the bolt 18 passes through the thrust bearing 25 and the radial bearing 26 disposed in the circular recess 18d. 18a is supported in the direction of the central axis and is rotatably supported around the central axis.
The crank chamber 20 communicates with the innermost part of the cylindrical space 11b ″ formed inside the second annular partition 11b of the rear housing 11 via a gas passage 21a formed at the other end of the main shaft 21. In addition, an annular gap between the surrounding wall of the center bore 17b and a sleeve 27, a main shaft 21, and a bolt head portion 18a described later, an annular gap formed in the valve plate 19 through portion of the bolt 18, and a male screw formed in the bolt body 18b 18b 'and the innermost surface of the cylindrical space 11b "through a spiral gap formed between the internal thread 11b' formed on the inner peripheral surface of the second annular surrounding wall 11b and the center bore. 17b, an annular gap between a surrounding wall and a sleeve 27, which will be described later, the main shaft 21, an internal space of the radial bearing 26, an opening 18e formed in the base of the bolt head 18a, and a valve plate 19 through portion of the bolt 18 Through the annular gap or the like formed in communication with the inlet portion of the cylindrical space 11b ".

A sleeve 27 is externally fitted to the main shaft 21 so as to be slidable in the central axis direction. The sleeve 27 is urged in a direction approaching the cylinder bore 17a by a coil spring 28 having one end abutting on a flange portion 21a formed on the main shaft 21 and the other end abutting on one end portion of the sleeve 27.
An annular plate-like swash plate 29 is supported by a sleeve 27 through a pair of opposed sleeve pins (not shown) so that the inclination angle of the main shaft 21 can be changed. The main shaft 21 is inserted through the swash plate 29.
One end of the pivot 30 is inserted into a slit 27 a formed in the sleeve 27 and is press-fitted and fixed at a right angle to the main shaft 21. A spherical portion 30 a is formed at the other end of the pivot 30. A pivot hole 29a is formed in the swash plate 29 so as to face the spherical portion 30a. The pivot hole 29a receives the spherical portion 30a so as to be slidable.

A single-headed piston 31 extending parallel to the main shaft 21 is inserted into the cylinder bore 17a so as to be able to reciprocate. A shoe holding portion 31 a is formed at one end of the piston 31. A pair of shoes 32 having a spherical surface and a flat surface facing the spherical surface are held by a shoe holding portion 31a. The flat surfaces of the pair of shoes 32 are in sliding contact with both end surfaces of the swash plate 29.

The innermost part of the cylindrical space 11b ″ formed inside the second annular partition 11b of the rear housing 11 communicates with the suction chamber 14 via the gas path 33a. A throttle device is provided along the gas path 33a. An inlet portion of a cylindrical space 11b ″ formed inside the second annular partition 11b of the rear housing 11 communicates with the discharge chamber 15 through a gas path 33b. A throttle device 34b is disposed in the middle of the gas path 33b. At least one of the expansion devices 34a and 34b includes an electromagnetic solenoid and a valve mechanism, and is configured by a valve that can variably control the opening degree by external control.

The swash plate compressor 1 is a cooling device for air conditioning of a vehicle, and operates so that the high-pressure side pressure of the closed circuit constituting the cooling device, that is, the discharge pressure of the compressor becomes the supercritical pressure of the refrigerant. It is used for a cycle cooling device. Carbon dioxide (CO2), ethylene (C2H4), diborane (B2H6), ethane (C2H6), nitrogen oxide (NO), etc. can be used as the refrigerant.

The operation of the swash plate compressor 1 will be described below.
The main shaft 21 is rotationally driven by a vehicle engine (not shown) via the electromagnetic clutch 24. The swash plate 29 is rotationally driven by the main shaft 21 via the pivot 30. The piston 31 is driven to reciprocate by a swash plate 29 through a pair of shoes 32. As the piston 31 reciprocates and slides, the refrigerant gas flowing into the suction chamber 14 through a suction port (not shown) is sucked into the cylinder bore 17a through the suction hole 19a formed in the valve plate 19 and the suction valve. It is compressed in 17a, discharged to the discharge chamber 15 through the discharge hole 19b formed in the valve plate 19 and the discharge valve, and flows out to the closed circuit of the cooling device for the vehicle through the discharge port 16.

The refrigerant gas in the discharge chamber 15 flows into the inlet portion of the cylindrical space 11b ″ through the gas path 33b and the expansion device 34b, and then flows into the crank chamber 20 communicating with the inlet portion of the cylindrical space 11b ″. The refrigerant gas in the crank chamber 20 flows into the innermost part of the cylindrical space 11b ″ communicating with the crank chamber 20, and then flows out into the suction chamber 14 through the gas path 33a and the expansion device 34a.
The flow rate of the refrigerant gas flowing from the discharge chamber 15 into the crank chamber 20 and / or the flow rate of the refrigerant gas flowing out from the crank chamber 20 into the suction chamber 14 is variably controlled by the external control. Is variably controlled, so that the internal pressure of the crank chamber 20 is variably controlled. By variably controlling the internal pressure of the crank chamber 20, the position of the sleeve 27 in the central axis direction on the main shaft 21 is variably controlled, and the relative position of the swash plate 29 slidably engaged with the spherical portion 30a with respect to the pivot 30 Is variably controlled, and the tilt angle of the swash plate 29 with respect to the main shaft 21 is variably controlled. As a result, the stroke of the piston 31 is variably controlled, and the discharge capacity of the swash plate compressor 1 is variably controlled.

In the swash plate compressor 1, by tightening the bolt 18, the valve plate 19 disposed between the cylinder block 17 and the rear housing 11 is attached to the end surface of the second annular partition 11b and the first annular partition 11a. The end face is in pressure contact, and leakage of high-pressure gas from the discharge chamber 15 to the suction chamber 14 is prevented. Since the second annular partition 11b into which the bolt 18 is screwed is disposed concentrically with the first annular partition 11a, the end surface of the first annular partition 11a generated by tightening the bolt 18 and the valve plate 19 are arranged. The surface pressure of the abutting portion is uniformly distributed in the circumferential direction. As a result, leakage of high-pressure gas from the discharge chamber 15 to the suction chamber 14 is effectively prevented. Therefore, even if the refrigerant gas is carbon dioxide and the refrigerant gas pressure in the discharge chamber 15 is an ultrahigh pressure exceeding 7.35 MPa, which is the critical pressure of carbon dioxide, the high-pressure refrigerant gas from the discharge chamber 15 to the suction chamber 14 Leakage is effectively prevented.
The fastening force of the single bolt 18 may be precisely managed, and it is not necessary to precisely manage the fastening force of a plurality of bolts. Therefore, the assembling cost of the swash plate compressor 1 is low. Since the cylinder block 17 is fixed to the rear housing 11 using a single bolt 18, the number of parts is smaller than that of the piston type compressor disclosed in Patent Document 1.
Since the bolt 18 is not screwed into the first annular partition 11a, the first annular partition 11a does not bulge locally inward and outward in the radial direction, and is formed radially outward of the first annular partition 11a. The annular suction chamber 14 and the annular discharge chamber 15 formed radially inward of the first annular partition wall 11a are not locally narrow. Therefore, the flow resistance of the annular suction chamber 14 and the discharge chamber 15 with respect to the refrigerant gas is small. Therefore, the swash plate compressor 1 has high performance.
Since the bolt 18 is not screwed into the first annular partition 11a, the first annular partition 11a does not bulge locally inward and outward in the radial direction, and is formed radially outward of the first annular partition 11a. The annular suction chamber 14 and the annular discharge chamber 15 formed radially inward of the first annular partition wall 11a are not locally narrow. Accordingly, the difference in pressure loss between the suction port and the cylinder bore 17a communicating with the suction port via the annular suction chamber 14 is small for each cylinder bore 17a, and the discharge port 16 and the annular discharge chamber are small. The difference in pressure loss between each cylinder bore 17a and the cylinder bore 17a communicating with the discharge port 16 via 15 is small. Therefore, the swash plate compressor 1 has high performance and low noise.
Since the cylindrical space 11b ″, which is the internal space of the second annular partition wall 11b, communicates with the crank chamber 20, the gas that communicates the crank chamber 20, the suction chamber 14, and the discharge chamber 15 for discharge capacity control. When the paths 33a and 33b are formed, one end of the gas paths 33a and 33b is communicated with the cylindrical space 11b ″ close to the suction chamber 14 and the discharge chamber 15 to thereby increase the path length of the gas paths 33a and 33b. The working cost of the gas paths 33a and 33b can be reduced.

By using the head portion 18a of the bolt 18 that fixes the cylinder block 17 to the rear housing 11 as a support member for the main shaft 21, the swash plate compressor 1 is downsized.
The through hole 18c formed in the bolt 18 for fixing the cylinder block 17 to the rear housing 11 is effective as a space for accommodating a filter for removing dust such as metal powder from the refrigerant gas flowing out from the crank chamber 20 to the suction chamber 14. Available. The swash plate compressor 1 is downsized compared to the case where a space for accommodating the filter is separately formed.
By making the bolt 18 made of steel, the entire bolt 18 including the bolt head 18a or the bolt main body 18b can be thinned, and the bolt 18 and thus the swash plate compressor 1 can be reduced in weight. The bolt 18 that supports the main shaft 21 via the bearings 25 and 26 is made of the same material as that of the steel main shaft 21 so that the radial gap between the main shaft 21 and the bolt head portion 18a at the bearing portion accompanying temperature change. , And the life of the bearings 25 and 26 can be extended.
By making the front housing 10, the rear housing 11, and the cylinder block 17 made of aluminum gold, the swash plate compressor 1 can be reduced in weight.

The discharge chamber 15 may be disposed radially outward of the first annular partition 11a, and the suction chamber 14 may be disposed radially inward of the first annular partition 11a.
In place of the single-head piston 31, a double-headed piston having two piston heads extending on both sides of the swash plate 29 is engaged with the swash plate 29, and a cylinder block having a cylinder bore into which one piston is inserted, and the cylinder A valve plate, a suction valve, a discharge valve, a suction chamber, and a discharge chamber facing the block may be additionally provided. In this case, the additional cylinder block fixed to the housing is different from the fixing using the bolt 18.
The end of the through hole 18c on the side away from the crank chamber 20 may be closed. In this case, the crank chamber 20 is formed between the inlet portion of the cylindrical space 11b ″, the external thread 18b ′ formed in the bolt body 18b, and the internal thread 11b ′ formed on the inner peripheral surface of the second annular surrounding wall 11b. Between the external thread 18b 'formed on the bolt main body 18b and the internal thread 11b' formed on the inner peripheral surface of the second annular surrounding wall 11b. Since the helical gap formed in the above functions as a throttle device, the throttle device 34a can be omitted, the number of parts is reduced, and the manufacturing cost of the swash plate compressor 1 is reduced.
A swash plate compressor in which a helical gap formed between a male screw 18b 'formed on the bolt body 18b and a female screw 11b' formed on the inner peripheral surface of the second annular surrounding wall 11b forms a throttle device 34b. 1 may be configured.
The present invention can be applied to various piston compressors such as a swash plate compressor in which a piston is directly engaged with a swash plate and a swing compressor in which a piston is engaged with a swash plate via a swing plate. The present invention is applicable to various piston compressors such as a variable capacity swash plate compressor, a swing compressor, a fixed capacity swash plate compressor, and a swing compressor.

  The present invention can be applied to various piston type compressors such as variable capacity and fixed capacity swash plate type compressors and swing type compressors.

It is sectional drawing of the swash plate type compressor which concerns on the Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Swash plate type compressor 10 Front housing 11 Rear housing 11a 1st annular partition 11b 2nd annular partition 11b '' Cylindrical space 14 Suction chamber 15 Discharge chamber 17 Cylinder block 18 Bolt 21 Main shaft 29 Swash plate 31 Piston 33a, 33b Gas Paths 34a, 34b

Claims (11)

A cylindrical cylinder block having a plurality of cylinder bores spaced apart from each other in the circumferential direction, a bottomed cylindrical first housing that forms a crank chamber on one end face side of the cylinder block, and the other cylinder block A cylindrical bottomed second housing that forms a suction chamber and a discharge chamber on the end face side, a main shaft that extends in parallel with the cylinder bore in the crank chamber, and a reciprocating motion in the cylinder bore that is inserted into the cylinder bore and driven by the rotation of the main shaft The second housing is arranged concentrically with the cylinder block and has an annular first partition wall that divides the suction chamber and the discharge chamber, and a second inner wall radially inward of the first partition wall. A first partition wall and an annular second partition wall disposed concentrically, an internal thread is formed on the inner peripheral surface of the second partition wall, and screwed into the second partition wall internal thread of the second housing from the crank chamber side Bo And the cylinder block is fixed to the second housing by preparative, piston compressor the interior space of the second partition wall, characterized in that in communication with the crank chamber. A circular recess having an open end on the crank chamber side is formed in the head of the bolt, and one end of the main shaft enters the circular recess and is rotatably supported by the head via a bearing. The piston type compressor according to claim 1. The piston type compressor according to claim 2, wherein the bolt is hollow. The piston type compressor according to claim 2 or 3, wherein the bolt is made of steel and the cylinder block is made of a light alloy. The piston according to any one of claims 1 to 4, wherein the suction chamber is formed radially outward of the first partition, and the discharge chamber is formed radially inward of the first partition. Type compressor. The piston according to any one of claims 1 to 4, wherein the suction chamber is formed radially inward of the first partition and the discharge chamber is formed radially outward of the first partition. Type compressor. The piston type compressor according to any one of claims 1 to 6, wherein the piston is a single-headed piston that engages with a swash plate supported by a main shaft so as to be synchronously rotatable. The piston engages with a swash plate supported by a main shaft so as to be able to rotate synchronously, and an inclination angle of the swash plate with respect to the main shaft is variable. A throttling device is disposed, a second throttling device is disposed in the middle of a gas path connecting the internal space of the second partition and the discharge chamber, and the opening degree of the first throttling device and / or the second throttling device is The piston type compressor according to any one of claims 1 to 6, wherein the piston type compressor is variable. The first diaphragm device or the second diaphragm device is a spiral space formed between a female screw formed on an inner peripheral surface of the second partition wall and a male screw formed on the bolt. Item 9. The piston type compressor according to Item 8. The piston compressor according to any one of claims 1 to 9, wherein the pressure of the discharge gas is a supercritical pressure. The piston-type compressor according to claim 10, wherein the discharge gas is carbon dioxide.

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