JP2021032236A - Piston type compressor - Google Patents

Abstract

To provide a piston type compressor capable of exerting controllability and realizing downsizing.SOLUTION: A second moving body portion 81 is moved integrally with a first moving body portion 71 on a guide window 60 in an axial direction of a drive shaft 47, by moving the first moving body portion 71 in a shaft path 57 in the axial direction of the drive shaft 47. Then, according to a position in the axial direction of the drive shaft 47 in the second moving body portion 81, a communication angle around an axis at which each rear side communication passage 29a, 29b, 29c, 29d, 29e and a moving body passage 82 communicate with each other changes per one rotation of the drive shaft 47. Each rear side communication passage 29a, 29b, 29c, 29d, 29e and the moving body passage 82 are prevented from communicating with each other by the drive shaft 47. Furthermore, one of a pair of guiding portions 85 has a stepped portion 87 continuing to the moving body passage 82 and recessed in a separating direction with respect to an inner peripheral surface of a shaft hole 48.SELECTED DRAWING: Figure 4

Description

The present invention relates to a piston type compressor.

The housing of the piston compressor has a cylinder block. A plurality of cylinder bores are formed in the cylinder block. Further, the housing is formed with a suction chamber, a discharge chamber, a swash plate chamber, and a shaft hole. In the piston type compressor, for example, the refrigerant from the outside of the piston type compressor may be sucked into the swash plate chamber. As described above, a piston type compressor in which the swash plate chamber functions as a suction chamber has been conventionally known.

A drive shaft is rotatably supported in the shaft hole. Further, the piston type compressor is provided with a fixed swash plate. The fixed swash plate can be rotated in the swash plate chamber by the rotation of the drive shaft. The fixed swash plate has a constant inclination angle with respect to a plane perpendicular to the drive axis. Further, the piston type compressor includes a piston connected to a fixed swash plate. The piston forms a compression chamber in the cylinder bore. Further, the piston type compressor is provided with a discharge valve that discharges the refrigerant in the compression chamber to the discharge chamber.

Then, the fixed swash plate rotates with the rotation of the drive shaft, so that each piston reciprocates in each cylinder bore between the top dead center and the bottom dead center. Here, as the piston moves from the top dead center to the bottom dead center, the compression chamber becomes a suction stroke. On the other hand, as the piston moves from the bottom dead center to the top dead center, the compression chamber becomes a compression stroke for compressing the sucked refrigerant, and further, the refrigerant compressed in the compression chamber is discharged through the discharge valve. It is a discharge stroke to discharge to.

In such a piston type compressor, for example, Patent Document 1 discloses a piston type compressor in which a moving body is provided on a drive shaft. The moving body rotates integrally with the drive shaft and can move with respect to the drive shaft in the axial direction of the drive shaft based on the control pressure controlled by the control valve. The cylinder block of the piston type compressor of Patent Document 1 is formed with a plurality of first communication passages communicating with each cylinder bore. Further, the moving body is formed with a second passage that intermittently communicates with the first passage as the drive shaft rotates.

Then, when the piston moves from the top dead center to the bottom dead center and the compression chamber becomes the suction stroke, the refrigerant is sucked into the compression chamber by communicating the first passage and the second passage. Will be done. Here, it is possible to change the communication angle around the axis at which the first passage and the second passage communicate with each other per rotation of the drive shaft according to the position of the drive shaft in the axial direction of the moving body. It has become. This makes it possible to change the flow rate of the refrigerant discharged from the compression chamber to the discharge chamber.

Japanese Unexamined Patent Publication No. 5-306680

In a piston type compressor as in Patent Document 1, the compression load, which is the load of the high-pressure refrigerant compressed in the compression chamber, is applied through the first communication passage communicating with the compression chamber during the compression stroke and the discharge stroke. Acts on moving objects. Then, the moving body is pressed in the shaft hole in the direction intersecting the axial direction of the drive shaft, and the moving body is pressed against the inner peripheral surface of the shaft hole. Therefore, when moving in the axial direction of the drive shaft. The frictional force between the moving body and the inner peripheral surface of the shaft hole increases. As a result, it becomes difficult for the moving body to move in the axial direction of the drive shaft, which may reduce controllability.

Therefore, it is conceivable to increase the pressure receiving area of the control pressure in the moving body so that the moving body can be moved in the axial direction of the drive shaft by a larger thrust. However, if the area for receiving the control pressure in the moving body is increased, the moving body becomes larger, and the shaft hole and the like also become larger as the moving body becomes larger, so that the piston type compressor becomes larger.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a piston type compressor that can exhibit high controllability and can be miniaturized.

The piston type compressor that solves the above problems has a cylinder block in which a plurality of cylinder bores are formed, and has a suction chamber, a discharge chamber, a swash plate chamber, a housing in which a shaft hole is formed, and the inside of the shaft hole. A drive shaft rotatably supported, a fixed swash plate that can be rotated in the swash plate chamber by the rotation of the drive shaft, and a constant inclination angle with respect to a plane perpendicular to the drive shaft, and inside each cylinder bore. A piston connected to the fixed swash plate, a discharge valve for discharging the refrigerant in the compression chamber to the discharge chamber, and a drive shaft provided on the drive shaft and rotating integrally with the drive shaft. A moving body that can move with respect to the drive shaft in the axial direction of the drive shaft based on the control pressure and a control valve that controls the control pressure are provided, and the cylinder block communicates with the cylinder bore. The moving body is formed with a second passage that intermittently communicates with the first passage as the drive shaft rotates, and the moving body is formed in the axial direction of the moving body. It is a piston type compressor in which the flow rate of the refrigerant discharged from the compression chamber to the discharge chamber changes according to the position, and the drive shaft has the inside of the drive shaft in the axial direction of the drive shaft. A guide that extends and communicates with the suction chamber and an outer peripheral surface of a portion of the drive shaft that communicates with the shaft and is located in the shaft hole to guide the moving body in the axial direction. A window is formed, the first communication passage and the second communication passage are communicated by the moving body, and the first communication passage and the second communication passage are not communicated by the drive shaft. The moving body is in a state of being engaged with a first moving body portion that is located in the axial path and moves in the axial direction in the axial path based on the control pressure, and the first moving body portion. It has a second moving body portion that is arranged in the guide window and has a curved plate shape that extends along the inner peripheral surface of the shaft hole and is formed in a state in which the second continuous passage penetrates. The guide window extends in the axial direction and has a pair of guide surfaces for guiding the second moving body portion, and the second moving body portion is located on both sides of the second moving body portion in the circumferential direction. Both edges of the second communication passage are formed, and at least a part thereof has a pair of guide portions guided by the pair of guide surfaces, and at least one of the pair of guide portions is in the second communication passage. It has a stepped portion that is continuous and recesses in a direction away from the inner peripheral surface of the shaft hole.

According to this, when the compression chamber becomes the suction stroke by moving the piston from the top dead center to the bottom dead center, the moving body communicates the first passage and the second passage from the suction chamber. The refrigerant is sucked into the compression chamber through the shaft path, the second passage, and the first passage. Here, based on the control pressure, the first moving body portion moves in the axial path in the axial direction of the drive shaft, so that the second moving body portion integrally with the first moving body portion in the guide window. The axis moves in the axial direction of the drive shaft, and the first and second passages communicate with each other per rotation of the drive shaft according to the position of the drive shaft in the axial direction in the second moving body. The communication angle around it changes. As a result, the flow rate of the refrigerant discharged from the compression chamber to the discharge chamber changes.

Here, the second moving body portion has a curved plate shape extending along the inner peripheral surface of the shaft hole, and in order to secure the rigidity of the second moving body portion, for example, the second moving body portion in the pair of guide portions. It is conceivable to increase the width of the portion in the circumferential direction. However, as the width of the second moving body portion in the pair of guide portions is increased, the width of the second moving body portion in the second continuous passage in the circumferential direction is reduced, so that the flow path of the second continuous passage is reduced. The area becomes smaller. As a result, it becomes difficult for the refrigerant to be sucked from the second passage into the first passage, and the controllability may be deteriorated.

Therefore, since at least one of the pair of guide portions has a stepped portion that is continuous with the second passage and is recessed in a direction away from the inner peripheral surface of the shaft hole, the stepped portion with the inner peripheral surface of the shaft hole. It can function as a flow path for guiding the refrigerant from the second continuous passage to the first continuous passage between the portions. Therefore, in order to secure the rigidity of the second moving body portion, even if the width in the circumferential direction of the second moving body portion in the pair of guide portions is increased, the refrigerant from the second continuous passage to the first continuous passage can be used. It is suppressed that inhalation becomes difficult.

Then, the first and second passages are not communicated with each other by the drive shaft, and the piston moves from the bottom dead center to the top dead center, so that the compression chamber becomes a compression stroke or a discharge stroke. As a result, the compression load, which is the load of the high-pressure refrigerant compressed in the compression chamber, acts on the drive shaft through the first continuous passage, while the compression load is less likely to act on the moving body. Therefore, since the moving body can easily move in the axial direction of the drive shaft, it is not necessary to make the moving body larger than necessary in order to obtain a large thrust. Therefore, it is possible to exhibit high controllability and realize miniaturization.

In the piston type compressor, the drive shaft is a portion located on the opposite side of the guide window with the axis of the drive shaft sandwiched, and communicates with the compression chamber during the compression stroke or the discharge stroke. The main body portion facing the first continuous passage, and the main body portion communicates with the compression chamber in the re-expansion stroke or the suction stroke, and the first continuous passage communicating with the compression chamber, which is a later stage of the compression stroke. It is preferable that the drive shaft is formed so as to extend more than half a circumference in the circumferential direction of the drive shaft along the inner peripheral surface of the shaft hole from between the first communication passage communicating with the compression chamber.

According to this, as the drive shaft rotates, the boundary between the main body and the second moving body in the circumferential direction of the drive shaft faces the first passage that communicates with the compression chamber, which is the latter stage of the compression stroke. There is nothing to do. Therefore, even if a backflow of the refrigerant occurs from the compression chamber, which is the latter stage of the compression stroke, toward the first passage, the refrigerant flows into the axial path through the boundary between the main body portion and the second moving body portion in the circumferential direction of the drive shaft. It is possible to prevent the refrigerant from leaking.

In the piston type compressor, of the pair of guide portions, the guide portion located on the leading side in the rotation direction of the drive shaft may have the step portion.
According to this, as the drive shaft rotates, the stepped portion faces the first passage at the timing before the second passage faces the first passage. Therefore, for example, in order to secure the rigidity of the second moving body portion, even if the width of the second moving body portion in the pair of guide portions in the circumferential direction is increased, the second continuous passage to the first continuous passage It is possible to avoid delaying the suction timing of the refrigerant.

According to the present invention, high controllability can be exhibited and miniaturization can be realized.

A side sectional view showing a piston type compressor in an embodiment. A side sectional view showing a state when the flow rate of the refrigerant gas discharged to the first discharge chamber and the second discharge chamber is maximum. FIG. 1 is a sectional view taken along line 3-3 in FIG. FIG. 1 is a sectional view taken along line 4-4 in FIG. FIG. 2 is a sectional view taken along line 5-5 in FIG. Exploded view showing a drive shaft, a moving body, a suction valve body, and the like. Side sectional view of the drive shaft. FIG. 7 is a cross-sectional view taken along the line 8-8 in FIG. FIG. 5 is an enlarged cross-sectional view showing the periphery of the second moving body portion when the flow rate of the refrigerant gas discharged to the second discharge chamber is the minimum. FIG. 5 is an enlarged cross-sectional view showing the periphery of the second moving body portion when the flow rate of the refrigerant gas discharged to the second discharge chamber is maximum. FIG. 5 is an enlarged cross-sectional view showing the periphery of the suction valve body when the flow rate of the refrigerant gas discharged to the first discharge chamber is the minimum. FIG. 5 is an enlarged cross-sectional view showing the periphery of the suction valve body when the flow rate of the refrigerant gas discharged to the first discharge chamber is maximum. FIG. 5 is an enlarged cross-sectional view showing a state in which the first moving body portion and the second moving body portion are assembled. The perspective view which shows the 1st moving body part, the 2nd moving body part, and a part of a drive shaft. The perspective view of the 2nd moving body part. The perspective view of the 2nd moving body part in another embodiment.

Hereinafter, an embodiment in which the piston type compressor is embodied will be described with reference to FIGS. 1 to 15. The piston type compressor of this embodiment is mounted on a vehicle, for example. Then, the piston type compressor is used in the vehicle air conditioner and compresses the refrigerant.

As shown in FIGS. 1 and 2, the piston compressor 10 includes a substantially cylindrical housing 11. The housing 11 includes a first cylinder block 12 and a second cylinder block 13 connected to each other, a front housing 14 connected to the first cylinder block 12, and a rear housing 15 connected to the second cylinder block 13. Have. The first cylinder block 12, the second cylinder block 13, the front housing 14, and the rear housing 15 have a substantially cylindrical shape made of a metal material made of, for example, aluminum. The axis of the first cylinder block 12, the axis of the second cylinder block 13, the axis of the front housing 14, and the axis of the rear housing 15 are the same.

A substantially disk-shaped first valve port forming plate 16 is interposed between the front housing 14 and the first cylinder block 12. Therefore, the front housing 14 is connected to the first cylinder block 12 via the first valve port forming plate 16. Further, a substantially disk-shaped second valve port forming plate 17 is interposed between the rear housing 15 and the second cylinder block 13. Therefore, the rear housing 15 is connected to the second cylinder block 13 via the second valve port forming plate 17.

A first cylinder recess 18 is formed on the end surface of the first cylinder block 12 on the second cylinder block 13 side. The first cylinder recess 18 has a circular hole shape. The axis of the first cylinder recess 18 coincides with the axis of the first cylinder block 12. Further, a circular hole-shaped first shaft hole 19 is formed in the central portion of the first cylinder block 12. The axis of the first shaft hole 19 coincides with the axis of the first cylinder block 12. The first shaft hole 19 penetrates the first cylinder block 12 in the axial direction. One end of the first shaft hole 19 opens to the bottom surface of the first cylinder recess 18, and the other end of the first shaft hole 19 opens to the end face of the first cylinder block 12 on the side of the first valve port forming plate 16. ing.

As shown in FIG. 3, the first cylinder block 12 is formed with the first cylinder bores 20a, 20b, 20c, 20d, 20e. Each of the first cylinder bores 20a, 20b, 20c, 20d, 20e has a circular hole shape. 1st cylinder bores 20a, 20b, 20c, 2 respectively
The inner diameters of 0d and 20e are the same, respectively. The first cylinder bores 20a, 20b, 20c, 20d, and 20e are arranged around the first shaft hole 19 at equal intervals in the circumferential direction of the first cylinder block 12.

As shown in FIGS. 1 and 2, each of the first cylinder bores 20a, 20b, 20c, 20d, and 20e penetrates the first cylinder block 12 in the axial direction. One end of each of the first cylinder bores 20a, 20b, 20c, 20d, 20e opens to the bottom surface of the first cylinder recess 18, and the other end of each of the first cylinder bores 20a, 20b, 20c, 20d, 20e is the first cylinder. It is open to the end face of the block 12 on the side of the first valve port forming plate 16.

As shown in FIG. 3, the front side connecting passages 21a, 21b, 21c, 21d, and 21e are formed in the first cylinder block 12. The front side passages 21a, 21b, 21c, 21d, 21e extend in the radial direction of the first cylinder block 12 from the first shaft hole 19 toward the first cylinder bores 20a, 20b, 20c, 20d, 20e. .. One end of each of the front side passages 21a, 21b, 21c, 21d, 21e communicates with the first shaft hole 19. The other ends of the front side passages 21a, 21b, 21c, 21d, and 21e communicate with the first cylinder bores 20a, 20b, 20c, 20d, and 20e, respectively.

As shown in FIGS. 1 and 2, the first cylinder block 12 is formed with a suction port 22, a first discharge passage 23, and a discharge port 24. The suction port 22 communicates with the first cylinder recess 18. The suction port 22 extends in the radial direction of the first cylinder block 12 and opens to the outside of the first cylinder block 12. The suction port 22 is connected to an external refrigerant circuit (not shown). Specifically, the suction port 22 is connected to an evaporator constituting an external refrigerant circuit via a pipe (not shown).

The first discharge passage 23 penetrates the first cylinder block 12 in the axial direction on the radial side of the first cylinder block 12 with respect to the first cylinder recess 18. One end of the first discharge passage 23 opens to the end surface of the first cylinder block 12 on the second cylinder block 13 side, and the other end of the first discharge passage 23 is a first valve port forming plate in the first cylinder block 12. It is open to the end face on the 16 side.

The discharge port 24 communicates with the first discharge passage 23. The discharge port 24 extends in the radial direction of the first cylinder block 12 and opens to the outside of the first cylinder block 12. The discharge port 24 is connected to an external refrigerant circuit. Specifically, the discharge port 24 is connected to a condenser constituting an external refrigerant circuit via a pipe (not shown).

A second cylinder recess 25 is formed on the end surface of the second cylinder block 13 on the first cylinder block 12 side. The second cylinder recess 25 has a circular hole shape. The axis of the second cylinder recess 25 coincides with the axis of the second cylinder block 13. Further, a cylindrical cylinder boss portion 26 is provided so as to project from the end surface of the second cylinder block 13 on the side of the second valve port forming plate 17. The axis of the cylinder boss portion 26 coincides with the axis of the second cylinder block 13.

A circular hole-shaped second shaft hole 27 is formed in the central portion of the second cylinder block 13. The axis of the second shaft hole 27 coincides with the axis of the second cylinder block 13. The second shaft hole 27 penetrates the second cylinder block 13 in the axial direction. One end of the second shaft hole 27 opens to the bottom surface of the second cylinder recess 25, and the other end of the second shaft hole 27 passes through the inside of the cylinder boss portion 26 and opens to the tip surface of the cylinder boss portion 26. doing. Therefore, the inside of the cylinder boss portion 26 forms a part of the second shaft hole 27. The inner diameter of the second shaft hole 27 is the same as the inner diameter of the first shaft hole 19.

As shown in FIGS. 4 and 5, the second cylinder block 13 is formed with second cylinder bores 28a, 28b, 28c, 28d, 28e as cylinder bores. Therefore, the second cylinder block 13 is a cylinder block in which a plurality of cylinder bores are formed. Each of the second cylinder bores 28a, 28b, 28c, 28d, 28e has a circular hole shape. The inner diameters of the second cylinder bores 28a, 28b, 28c, 28d, and 28e are the same. The inner diameters of the second cylinder bores 28a, 28b, 28c, 28d, and 28e are the same as the inner diameters of the first cylinder bores 20a, 20b, 20c, 20d, and 20e. The second cylinder bores 28a, 28b, 28c, 28d, and 28e are arranged around the second shaft hole 27 at equal intervals in the circumferential direction of the second cylinder block 13.

As shown in FIGS. 1 and 2, each of the second cylinder bores 28a, 28b, 28c, 28d, 28e penetrates the second cylinder block 13 in the axial direction. One end of each of the second cylinder bores 28a, 28b, 28c, 28d, 28e opens to the bottom surface of the second cylinder recess 25, and the other end of each of the second cylinder bores 28a, 28b, 28c, 28d, 28e is the second cylinder. It is open to the end face of the block 13 on the side of the second valve port forming plate 17.

As shown in FIGS. 4 and 5, rear side passages 29a, 29b, 29c, 29d, and 29e are formed in the second cylinder block 13. The rear side passages 29a, 29b, 29c, 29d, 29e extend in the radial direction of the second cylinder block 13 from the second shaft hole 27 toward the second cylinder bores 28a, 28b, 28c, 28d, 28e. .. One end of each of the rear side passages 29a, 29b, 29c, 29d, 29e communicates with the second shaft hole 27. The other ends of the rear side passages 29a, 29b, 29c, 29d, and 29e communicate with the second cylinder bores 28a, 28b, 28c, 28d, and 28e, respectively. Therefore, the rear side communication passages 29a, 29b, 29c, 29d, 29e are first communication passages in which the second cylinder block 13 is formed and communicates with the second cylinder bores 28a, 28b, 28c, 28d, 28e.

As shown in FIGS. 1 and 2, a second discharge passage 30 is formed in the second cylinder block 13. The second discharge passage 30 is radially outside the second cylinder block 13 from the second cylinder recess 25 and penetrates the second cylinder block 13 in the axial direction. One end of the second discharge passage 30 opens to the end surface of the second cylinder block 13 on the first cylinder block 12 side, and the other end of the second discharge passage 30 is a second valve port forming plate in the second cylinder block 13. It is open to the end face on the 17 side.

A gasket 31 is interposed between the first cylinder block 12 and the second cylinder block 13. The gasket 31 seals between the first cylinder block 12 and the second cylinder block 13. The gasket 31 is formed with a first gasket hole 31a that communicates the first cylinder recess 18 and the second cylinder recess 25. Further, the gasket 31 is formed with a second gasket hole 31b that communicates the first discharge passage 23 and the second discharge passage 30.

The swash plate chamber 32 is partitioned between the first cylinder block 12 and the second cylinder block 13 by the first cylinder recess 18, the first gasket hole 31a, and the second cylinder recess 25. Therefore, the swash plate chamber 32 is formed in the housing 11. The low-pressure refrigerant gas that has passed through the evaporator is sucked into the swash plate chamber 32 from the external refrigerant circuit through the suction port 22. Therefore, the swash plate chamber 32 functions as a suction chamber in which the refrigerant gas is sucked from the outside of the piston type compressor 10.

Further, the first cylinder bores 20a, 20b, 20c, 20d, 20e and the second cylinder bores 28a, 28b, 28c, 28d, 28e face each other via the swash plate chamber 32 in a state where the axes are aligned with each other. There is. Further, the first shaft hole 19 and the second shaft hole 27 face each other via the swash plate chamber 32 in a state where the axes are aligned with each other.

A circular hole-shaped front shaft hole 33 is formed in the central portion of the front housing 14. The axis of the front shaft hole 33 coincides with the axis of the front housing 14. Further, a cylindrical front boss portion 34 is projected from the end surface of the front housing 14 on the side opposite to the first valve port forming plate 16. The axis of the front boss portion 34 coincides with the axis of the front housing 14. One end of the front shaft hole 33 opens to the end surface of the front housing 14 on the first valve port forming plate 16 side, and the other end of the front shaft hole 33 passes through the inside of the front boss portion 34 to the front boss portion 34. There is an opening on the tip surface of. Therefore, the inside of the front boss portion 34 forms a part of the front shaft hole 33.

An annular front recess 35 extending around the axis of the front housing 14 is formed on the end surface of the front housing 14 on the side of the first valve port forming plate 16. The front recess 35 extends annularly around the front shaft hole 33. The front recess 35 and the first valve port forming plate 16 partition the first discharge chamber 36 between the front housing 14 and the first valve port forming plate 16. Therefore, the first discharge chamber 36 extends in an annular shape around the axis of the front shaft hole 33.

The first valve port forming plate 16 has a first valve plate 37, a first discharge valve plate 38, and a first retainer plate 39. The first valve plate 37, the first discharge valve plate 38, and the first retainer plate 39 have a substantially disk shape. The first valve plate 37 is formed with first discharge holes 37a communicating with the first cylinder bores 20a, 20b, 20c, 20d, and 20e, respectively. The first cylinder bores 20a, 20b, 20c, 20d, and 20e communicate with the first discharge chamber 36 via the first discharge holes 37a.

The first valve plate 37 is joined to the end surface of the first cylinder block 12 on the front housing 14 side. The first retainer plate 39 is joined to the end surface of the front housing 14 on the first cylinder block 12 side. The first discharge valve plate 38 is interposed between the first valve plate 37 and the first retainer plate 39. The first discharge valve plate 38 is provided with a plurality of first discharge reed valves 38a capable of opening and closing each of the first discharge holes 37a. The first retainer plate 39 regulates the maximum opening degree due to elastic deformation of the first discharge reed valve 38a.

Further, a circular hole-shaped first plate through hole 16a is formed in the central portion of the first valve port forming plate 16. The first plate through hole 16a penetrates the first valve plate 37, the first discharge valve plate 38, and the first retainer plate 39. The inner diameter of the first plate through hole 16a is larger than the inner diameter of the first shaft hole 19. The axis of the first plate through hole 16a coincides with the axis of the first shaft hole 19. The first plate through hole 16a communicates the first shaft hole 19 and the front shaft hole 33.

Further, the first plate communication hole 16b is formed in the first valve port forming plate 16. The first plate communication hole 16b is located radially outside the first valve port forming plate 16 with respect to each of the first discharge holes 37a. The first plate communication hole 16b penetrates the first valve plate 37, the first discharge valve plate 38, and the first retainer plate 39. The first plate communication hole 16b communicates the first discharge chamber 36 and the first discharge passage 23. The first discharge chamber 36 communicates with the discharge port 24 via the first plate communication hole 16b and the first discharge passage 23.

A circular hole-shaped chamber forming recess 40 is formed in the central portion of the rear housing 15. The axis of the chamber forming recess 40 coincides with the axis of the rear housing 15. The inner diameter of the chamber forming recess 40 is slightly larger than the outer diameter of the cylinder boss portion 26.

An annular rear recess 41 extending around the axis of the rear housing 15 is formed on the end surface of the rear housing 15 on the side of the second valve port forming plate 17. The rear recess 41 extends in an annular shape around the chamber forming recess 40. A second discharge chamber 42 as a discharge chamber is partitioned between the rear housing 15 and the second valve port forming plate 17 by the rear recess 41 and the second valve port forming plate 17. Therefore, the second discharge chamber 42 extends in an annular shape around the axis of the chamber forming recess 40.

The second valve port forming plate 17 has a second valve plate 43, a second discharge valve plate 44, and a second retainer plate 45. The second valve plate 43, the second discharge valve plate 44, and the second retainer plate 45 have a substantially disk shape. The second valve plate 43 is formed with a second discharge hole 43a communicating with each of the second cylinder bores 28a, 28b, 28c, 28d, 28e. The second cylinder bores 28a, 28b, 28c, 28d, 28e communicate with the second discharge chamber 42 via the second discharge holes 43a.

The second valve plate 43 is joined to the end surface of the second cylinder block 13 on the rear housing 15 side. The second retainer plate 45 is joined to the end surface of the rear housing 15 on the side of the second cylinder block 13. The second discharge valve plate 44 is interposed between the second valve plate 43 and the second retainer plate 45. The second discharge valve plate 44 is provided with a plurality of second discharge reed valves 44a capable of opening and closing each of the second discharge holes 43a. The second retainer plate 45 regulates the maximum opening degree due to elastic deformation of the second discharge reed valve 44a.

Further, a circular hole-shaped second plate through hole 17a is formed in the central portion of the second valve port forming plate 17. The second plate through hole 17a penetrates the second valve plate 43, the second discharge valve plate 44, and the second retainer plate 45. The inner diameter of the second plate through hole 17a is the same as the inner diameter of the chamber forming recess 40. The axis of the second plate through hole 17a coincides with the axis of the chamber forming recess 40. The second plate through hole 17a communicates with the chamber forming recess 40.

Further, the second plate communication hole 17b is formed in the second valve port forming plate 17. The second plate communication hole 17b is located radially outside the second valve port forming plate 17 with respect to each of the second discharge holes 43a. The second plate communication hole 17b penetrates the second valve plate 43, the second discharge valve plate 44, and the second retainer plate 45. The second plate communication hole 17b communicates the second discharge chamber 42 with the second discharge passage 30.

The first discharge chamber 36 and the second discharge chamber 42 communicate with each other through the first plate communication hole 16b, the first discharge passage 23, the second gasket hole 31b, the second discharge passage 30, and the second plate communication hole 17b. doing. The second discharge chamber 42 communicates with the discharge port 24 via the second plate communication hole 17b, the second discharge passage 30, the second gasket hole 31b, and the first discharge passage 23.

The cylinder boss portion 26 is inserted into the chamber forming recess 40 via the second plate through hole 17a. The control pressure chamber 46 is partitioned by the tip surface of the cylinder boss portion 26 and the chamber forming recess 40. Therefore, the control pressure chamber 46 is formed in the rear housing 15. The control pressure chamber 46 is formed in the central portion of the rear housing 15. The second discharge chamber 42 extends in an annular shape around the control pressure chamber 46.

The piston type compressor 10 includes a drive shaft 47. The drive shaft 47 is housed in the housing 11 so that the axial direction of the drive shaft 47 coincides with the axial direction of the housing 11. The drive shaft 47 is made of steel, for example, and has rigidity capable of withstanding a compressive load of a high-pressure refrigerant gas. The drive shaft 47 is inserted into each of the first shaft hole 19, the second shaft hole 27, and the front shaft hole 33, and is rotatably supported in the first shaft hole 19 and the second shaft hole 27. As a result, the drive shaft 47 is rotatably supported by the housing 11. Therefore, the first shaft hole 19 and the second shaft hole 27 form a shaft hole 48 formed in the housing 11 and supporting the drive shaft 47.

One end of the drive shaft 47 is located in the front shaft hole 33, and the other end of the drive shaft 47 projects from the tip surface of the cylinder boss portion 26 and is located in the control pressure chamber 46. A shaft sealing device 49 is provided between the inner peripheral surface of the front shaft hole 33 and the outer peripheral surface of the drive shaft 47. The shaft sealing device 49 seals between the inside of the housing 11 and the outside of the housing 11. The drive shaft 47 is formed with a screw hole 47a that opens on one end surface of the drive shaft 47. A pulley, an electromagnetic clutch, or the like (not shown) is connected to the screw hole 47a. The drive shaft 47 is connected to the engine of the vehicle via a pool or an electromagnetic clutch.

The piston type compressor 10 includes a fixed swash plate 50. The fixed swash plate 50 is fixed to the drive shaft 47 by being press-fitted into the drive shaft 47. The fixed swash plate 50 is housed in the swash plate chamber 32. The fixed swash plate 50 can rotate integrally with the drive shaft 47 in the swash plate chamber 32 by the rotation of the drive shaft 47. The fixed swash plate 50 has a constant inclination angle with respect to a plane perpendicular to the drive shaft 47. The fixed swash plate 50 is supported by the first cylinder block 12 via the first thrust bearing 51a. Further, the fixed swash plate 50 is supported by the second cylinder block 13 via the second thrust bearing 51b.

The piston type compressor 10 includes a plurality of pistons 52 connected to the fixed swash plate 50. Each piston 52 has a first head 52a, a second head 52b, and a connecting portion 52c. Therefore, the piston type compressor 10 of the present embodiment is a double-headed piston type compressor. The first head 52a of each piston 52 is housed in each of the first cylinder bores 20a, 20b, 20c, 20d, 20e, respectively. Then, as shown in FIG. 3, the first head 52a and the first valve port forming plate 16 make the first compression chambers 53a, 53b, 53c in the first cylinder bores 20a, 20b, 20c, 20d, 20e, respectively. , 53d, 53e, respectively. The first compression chambers 53a, 53b, 53c, 53d, and 53e communicate with the front side passages 21a, 21b, 21c, 21d, and 21e, respectively.

As shown in FIGS. 1 and 2, the second head 52b of each piston 52 is housed in each of the second cylinder bores 28a, 28b, 28c, 28d, 28e, respectively. Then, as shown in FIGS. 4 and 5, the second head 52b and the second valve port forming plate 17 form a second compression chamber in each of the second cylinder bores 28a, 28b, 28c, 28d, 28e. The compression chambers 54a, 54b, 54c, 54d, and 54e are formed, respectively. Therefore, each piston 52 forms the second compression chambers 54a, 54b, 54c, 54d, 54e in the second cylinder bores 28a, 28b, 28c, 28d, 28e. The second compression chambers 54a, 54b, 54c, 54d, 54e communicate with the rear side passages 29a, 29b, 29c, 29d, 29e, respectively.

As shown in FIGS. 1 and 2, the connecting portion 52c connects the first head 52a and the second head 52b. A pair of hemispherical shoes 55 are provided in the connecting portion 52c. Each piston 52 is moored to the outer peripheral portion of the fixed swash plate 50 via a pair of shoes 55. The pair of shoes 55 converts the rotation of the fixed swash plate 50 into the reciprocating motion of each piston 52. This will
In each piston 52, the first head 52a reciprocates within the first cylinder bores 20a, 20b, 20c, 20d, 20e between the top dead center and the bottom dead center of the first head 52a, and the second head The portion 52b reciprocates in the second cylinder bores 28a, 28b, 28c, 28d, 28e between the top dead center and the bottom dead center of the second head 52b.

When the fixed swash plate 50 rotates in the swash plate chamber 32 with the rotation of the drive shaft 47, the first head 52a of each piston 52 has a top dead center in each of the first cylinder bores 20a, 20b, 20c, 20d, 20e. The second head 52b reciprocates between the top dead center and the bottom dead center, and the second head 52b reciprocates in the second cylinder bores 28a, 28b, 28c, 28d, 28e between the top dead center and the bottom dead center. As a result, in the first compression chambers 53a, 53b, 53c, 53d, 53e and the second compression chambers 54a, 54b, 54c, 54d, 54e, the re-expansion stroke, the suction stroke, the compression stroke, and the discharge stroke are repeated. It is said.

In the re-expansion stroke, the refrigerant gas inside each of the first compression chambers 53a, 53b, 53c, 53d, 53e and each second compression chamber 54a, 54b, 54c, 54d, 54e re-expands. In the suction stroke, the refrigerant gas is sucked into the first compression chambers 53a, 53b, 53c, 53d, 53e and the second compression chambers 54a, 54b, 54c, 54d, 54e. In the compression stroke, the refrigerant gas inside each of the first compression chambers 53a, 53b, 53c, 53d, 53e and the second compression chambers 54a, 54b, 54c, 54d, 54e is compressed.

In the discharge stroke, the refrigerant gas compressed in each of the first compression chambers 53a, 53b, 53c, 53d, 53e is discharged to the first discharge chamber 36 by elastic deformation of each first discharge lead valve 38a, and each first. 2 The refrigerant gas compressed in the compression chambers 54a, 54b, 54c, 54d, 54e is discharged to the second discharge chamber 42 by elastic deformation of each second discharge lead valve 44a. Therefore, each of the second discharge reed valves 44a is a discharge valve that discharges the refrigerant in each of the second compression chambers 54a, 54b, 54c, 54d, 54e to the second discharge chamber 42. The refrigerant gas discharged into the first discharge chamber 36 is discharged to the condenser of the external refrigerant circuit through the first plate communication hole 16b, the first discharge passage 23, and the discharge port 24. The refrigerant gas discharged into the second discharge chamber 42 of the external refrigerant circuit passes through the second plate communication hole 17b, the second discharge passage 30, the second gasket hole 31b, the first discharge passage 23, and the discharge port 24. It is discharged to the condenser.

The fixed swash plate 50 has a tubular swash plate boss portion 50a fixed to the outer peripheral surface of the drive shaft 47. The fixed swash plate 50 is attached to the drive shaft 47 by fixing the swash plate boss portion 50a to the outer peripheral surface of the drive shaft 47. A swash plate suction hole 56 is formed in the swash plate boss portion 50a. The swash plate suction hole 56 extends in the radial direction of the drive shaft 47 and penetrates the swash plate boss portion 50a. Therefore, the swash plate suction hole 56 communicates with the swash plate chamber 32.

As shown in FIGS. 6 and 7, the drive shaft 47 is formed with an axis 57, a first path 58, a second path 59, and a guide window 60. The axis 57 has a circular hole shape. The axis 57 extends inside the drive shaft 47 in the axial direction of the drive shaft 47. The shaft path 57 opens at the end surface of the drive shaft 47 opposite to the end surface of the drive shaft 47 through which the screw hole 47a opens, and extends toward the screw hole 47a. The axis 57 has a large-diameter road 61 and a small-diameter road 62 having an inner diameter smaller than that of the large-diameter road 61. The large-diameter road 61 is located on the opposite side of the small-diameter road 62 from the screw hole 47a. The large-diameter path 61 is opened on the end surface on the side opposite to the end surface of the drive shaft 47 through which the screw hole 47a is opened. The inner peripheral surface of the large-diameter road 61 and the inner peripheral surface of the small-diameter road 62 are connected by an annular stepped surface 63 extending in the radial direction of the drive shaft 47.

The first path 58 extends in the radial direction of the drive shaft 47. One end of the first path 58 is open to the inner peripheral surface of the small path 62, and the other end of the first path 58 is open to the outer peripheral surface of the drive shaft 47. As shown in FIGS. 1 and 2, the fixed swash plate 50 is attached to the drive shaft 47 so that the swash plate suction hole 56 communicates with the first path 58. As a result, the small path 62 of the axis 57 communicates with the swash plate chamber 32 via the first path 58 and the swash plate suction hole 56.

As shown in FIGS. 6 and 7, the second path 59 extends in the radial direction of the drive shaft 47. The second path 59 is located closer to the screw hole 47a on the drive shaft 47 than the first path 58. One end of the second path 59 is open to the inner peripheral surface of the small path 62, and the other end of the second path 59 is open to the outer peripheral surface of the drive shaft 47. As shown in FIG. 3, the second path 59 extends in the radial direction of the drive shaft 47 near the small path 62, and extends in the radial direction of the drive shaft 47 near the outer peripheral surface of the drive shaft 47. And it extends in the circumferential direction of the drive shaft 47.

As shown in FIGS. 6 and 7, the guide window 60 is formed by cutting out a part of the outer peripheral surface of the drive shaft 47. The guide window 60 communicates with the large-diameter road 61 of the shaft road 57 and opens on the outer peripheral surface of the drive shaft 47. The guide window 60 extends in the axial direction of the drive shaft 47. On the other hand, the drive shaft 47 has a main body portion 64 which is a portion located on the opposite side of the guide window 60 with the axis L1 of the drive shaft 47 interposed therebetween.

As shown in FIG. 8, the guide window 60 is formed smaller than half a circumference in the circumferential direction of the drive shaft 47. Specifically, the guide window 60 has a region extending in the circumferential direction of the drive shaft 47 of 90 ° or more and less than 180 °. The main body 64 has a semicircular gutter shape extending in the axial direction of the drive shaft 47. The main body 64 is formed larger than a half circumference in the circumferential direction of the drive shaft 47. Specifically, the main body 64 has a region extending in the circumferential direction of the drive shaft 47 of 180 ° or more and less than 270 °.

As shown in FIGS. 6 and 7, the guide window 60 is located on the side opposite to the second path 59 with the axis L1 of the drive shaft 47 interposed therebetween. Therefore, the guide window 60 and the second path 59 are formed on the drive shaft 47 with their phases shifted by about 180 °. Further, the first route 58 is formed on the drive shaft 47 in a state where the phase is shifted by about 90 ° with respect to the guide window 60 and the second route 59.

The guide window 60 has a first regulation surface 65, a second regulation surface 66, and a pair of guide surfaces 67. The first regulation surface 65 and the second regulation surface 66 extend in a plane in the radial direction of the drive shaft 47 and extend in parallel with each other. The first regulation surface 65 and the second regulation surface 66 face each other in the axial direction of the drive shaft 47. The first regulation surface 65 is located on the opening side of the large-diameter road 61 with respect to the second regulation surface 66, and the second regulation surface 66 is located on the step surface 63 side with respect to the first regulation surface 65. The pair of guide surfaces 67 connect the first regulation surface 65 and the second regulation surface 66, and extend in a plane in the axial direction of the drive shaft 47. The pair of guide surfaces 67 form end surfaces located on both sides of the drive shaft 47 in the main body 64 in the circumferential direction.

An annular mounting groove 68 is formed on the outer peripheral surface of the drive shaft 47. The mounting groove 68 is formed on the outer peripheral surface of the drive shaft 47 at a portion closer to the end surface on the side opposite to the end surface of the drive shaft 47 in which the screw hole 47a opens from the guide window 60. A seal ring 69 is mounted in the mounting groove 68.

As shown in FIGS. 9 and 10, the large-diameter path 61 of the axis 57 communicates with the control pressure chamber 46. The seal ring 69 seals between the outer peripheral surface of the drive shaft 47 and the inner peripheral surface of the second shaft hole 27. The guide window 60 is located in the second shaft hole 27. Therefore, the guide window 60 is open on the outer peripheral surface of the portion of the drive shaft 47 located in the shaft hole 48. The guide window 60 faces the rear side passages 29a, 29b, 29c, 29d, and 29e in the second shaft hole 27 while opening in the second shaft hole 27.

As shown in FIGS. 4 and 5, the guide window 60 has the second compression chambers 54a, 54b, 54c, which are in the re-expansion stroke or the suction stroke, among the rear side passages 29a, 29b, 29c, 29d, 29e. It faces the rear side passages 29a, 29b, 29c, 29d, and 29e that communicate with 54d and 54e. On the other hand, the main body 64 faces the rear side passages 29a, 29b, 29c, 29d, 29e communicating with the second compression chambers 54a, 54b, 54c, 54d, 54e during the compression stroke or the discharge stroke.

As shown in FIGS. 11 and 12, the second path 59 is located in the first shaft hole 19. Therefore, the second path 59 is open to the outer peripheral surface of the portion of the drive shaft 47 located in the shaft hole 48. The second route 59 faces the front side passages 21a, 21b, 21c, 21d, and 21e in the first shaft hole 19 while opening in the first shaft hole 19. The second route 59 communicates the front side passages 21a, 21b, 21c, 21d, 21e with the axis 57.

As shown in FIG. 6, the piston type compressor 10 includes a moving body 70. The moving body 70 has a first moving body portion 71 and a second moving body portion 81. The first moving body portion 71 has a first main body portion 72 and a first shaft portion 73. The first main body 72 has a columnar shape. The first shaft portion 73 is an elongated columnar shape having an outer diameter smaller than that of the first main body portion 72. The first shaft portion 73 projects from the central portion of one end surface 72a of the first main body portion 72. The axis of the first main body 72 and the axis of the first shaft 73 coincide with each other. A suction valve body 74 is provided at the tip of the first shaft portion 73. The suction valve body 74 has a columnar shape. The outer diameter of the suction valve body 74 is larger than the outer diameter of the first shaft portion 73 and smaller than the outer diameter of the first main body portion 72.

As shown in FIG. 13, the first moving body portion 71 is inserted into the axial path 57 from the opening of the large-diameter path 61 of the axial path 57 and is located in the axial path 57. The outer diameter of the first main body portion 72 is substantially the same as the inner diameter of the large diameter path 61 of the axial path 57. An annular mounting groove 75 is formed on the outer peripheral surface of the first main body 72. A seal ring 76 is provided in the mounting groove 75. The seal ring 76 seals between the outer peripheral surface of the first main body 72 and the inner peripheral surface of the large-diameter road 61. An annular engaging groove 77 is formed on the outer peripheral surface of the first main body 72. The engaging groove 77 is formed at a portion closer to the first shaft portion 73 than the mounting groove 75 on the outer peripheral surface of the first main body portion 72. The outer diameter of the first shaft portion 73 is smaller than the inner diameter of the small diameter path 62 of the shaft path 57. As shown in FIGS. 11 and 12, the outer diameter of the suction valve body 74 is substantially the same as the inner diameter of the small diameter path 62 of the shaft path 57.

As shown in FIGS. 14 and 15, the second moving body portion 81 has a curved plate shape formed smaller than half a circumference in the circumferential direction of the drive shaft 47. The second moving body portion 81 is formed, for example, by press-molding a flat plate of a thin plate. The second moving body portion 81 is arranged in the guide window 60 and extends around the axis of the drive shaft 47 between the pair of guide surfaces 67. The circumferential direction of the second moving body portion 81 coincides with the circumferential direction of the drive shaft 47.

In the second moving body portion 81, the region extending in the circumferential direction of the second moving body portion 81 is 90 ° or more and less than 180 °. The second moving body portion 81 extends in the axial direction of the drive shaft 47 in the guide window 60. The length of the drive shaft 47 in the second moving body portion 81 in the axial direction is set shorter than the length of the drive shaft 47 in the guide window 60 in the axial direction.

A moving body passage 82 is formed in the second moving body portion 81. The moving body passage 82 penetrates the second moving body portion 81 in the plate thickness direction. Therefore, the second moving body portion 81 is formed in a state in which the moving body passage 82 penetrates. In the moving body passage 82, the flow path area of the second moving body portion 81 in the circumferential direction gradually increases from one end to the other end of the drive shaft 47 in the second moving body portion 81 in the axial direction. It is formed.

The moving body passage 82 has a large opening 83 having a large flow path area in the circumferential direction of the second moving body portion 81 and a flow path area larger than that of the large opening 83 in the circumferential direction of the second moving body portion 81. It has a small opening 84 formed small. The large opening 83 and the small opening 84 are arranged side by side in the axial direction of the drive shaft 47 and communicate with each other. The small opening 84 is located on one end side of the second moving body portion 81 in the axial direction of the drive shaft 47 with respect to the large opening 83. When the moving body passage 82 is viewed in a plan view, the large opening 83 has an elongated rectangular shape, and the longitudinal direction coincides with the circumferential direction of the second moving body portion 81.

The second moving body portion 81 forms both edges of the moving body passage 82 located on both sides of the second moving body portion 81 in the circumferential direction, and has a pair of guide portions 85 guided by the pair of guide surfaces 67. doing. The pair of guide portions 85 have an elongated thin plate shape. One of the pair of guide portions 85 forms an edge portion located in one of the circumferential directions of the second moving body portion 81 in the large opening portion 83 and the small opening portion 84. The other side of the pair of guide portions 85 forms an edge portion located on the other side in the circumferential direction of the second moving body portion 81 in the large opening portion 83.

Further, the second moving body portion 81 includes a curved plate-shaped first curved portion 81a and a second curved portion 81b that form both edge portions located on both sides of the drive shaft 47 in the moving body passage 82 in the axial direction. Have. The first curved portion 81a and the second curved portion 81b face each other in the axial direction of the drive shaft 47 via the moving body passage 82. The first curved portion 81a and the second curved portion 81b connect the pair of guide portions 85 to each other. The edge of the moving body passage 82 formed by the first curved portion 81a extends in a direction orthogonal to the axial direction of the drive shaft 47 when the moving body passage 82 is viewed in a plan view, and is formed by the large opening 83. It forms an edge. The edge of the moving body passage 82 formed by the second curved portion 81b extends in a direction obliquely intersecting the axial direction of the drive shaft 47 when the moving body passage 82 is viewed in a plan view, and the small opening 84 Forming the edge of. The pair of guide portions 85, the first curved portion 81a, and the second curved portion 81b form an inner peripheral edge 82a of the moving body passage 82.

The second moving body portion 81 has an engaging protrusion 86 that engages with the engaging groove 77 of the first moving body portion 71. The engaging protrusion 86 has a flat plate shape that protrudes from the central portion in the circumferential direction of the second moving body portion 81 at the edge portion of the moving body passage 82 formed by the first curved portion 81a. Therefore, the engaging protrusion 86 projects from the inner peripheral edge 82a of the moving body passage 82. The engaging protrusion 86 extends from the first curved portion 81a in the axial direction of the drive shaft 47, is then bent toward the inside of the guide window 60, and extends toward the inside of the guide window 60. Therefore, the engaging protrusion 86 is arranged at a portion that overlaps the inside of the guide window 60 in the radial direction of the drive shaft 47. The plate thickness direction of the tip of the engaging protrusion 86 coincides with the axial direction of the drive shaft 47. The tip of the engaging protrusion 86 can be engaged with the engaging groove 77 of the first main body 72.

One of the pair of guide portions 85 has a step portion 87 that is continuous with the moving body passage 82 and is recessed in a direction away from the inner peripheral surface of the shaft hole 48. The step portion 87 has an elongated thin plate shape that forms a part of one of the pair of guide portions 85. Therefore, a part of one outer surface of the pair of guide portions 85 is recessed in a direction away from the inner peripheral surface of the shaft hole 48. In the present embodiment, one of the pair of guide portions 85 has a step portion 87 at a portion near the small opening 84.

When the drive shaft 47 rotates in the direction of the arrow R1 shown in FIG. 14, the guide portion 85 having the step portion 87 among the pair of guide portions 85 is located on the leading side in the rotation direction of the drive shaft 47. , Arranged with respect to the guide window 60. The second moving body portion 81 is arranged with respect to the guide window 60 so that the large opening 83 is located closer to the first regulation surface 65 than the small opening 84. Of the pair of guide portions 85, the guide portion 85 located on the leading side in the rotation direction of the drive shaft 47 has a step portion 87.

The step portion 87 overlaps the guide surface 67 of the guide window 60 in the circumferential direction of the drive shaft 47, and is located on the guide surface 67. Therefore, the distance of the step portion 87 from the inner peripheral surface of the shaft hole 48 is set to the distance at which the step portion 87 is located on the guide surface 67. Then, the step portion 87 is guided to the guide surface 67.

As shown in FIGS. 11 and 12, the suction valve body 74 is located in the small path 62 of the shaft path 57. Further, as shown in FIG. 13, the first main body portion 72 of the first moving body portion 71 is located in the large-diameter path 61 of the axial path 57. A part of the engaging groove 77 always faces the guide window 60 regardless of the orientation of the first moving body portion 71 in the circumferential direction when it is inserted into the axial path 57. Inhalation pressure acts from the swash plate chamber 32 on one end surface 72a of the first main body 72 via the swash plate suction hole 56, the first path 58, and the shaft path 57. On the other hand, the control pressure of the control pressure chamber 46 acts on the other end surface 72b of the first main body portion 72 on the side opposite to the first shaft portion 73.

As shown in FIGS. 9 and 10, the second moving body portion 81 is provided in the guide window 60 so as to be on the side opposite to the main body portion 64 of the drive shaft 47 with the axis L1 of the drive shaft 47 interposed therebetween. It is located and exposed in the second shaft hole 27. The second moving body portion 81 extends along the inner peripheral surface of the second shaft hole 27. The second moving body portion 81 is provided in the guide window 60 to form a cylindrical body having an outer diameter substantially the same as the inner diameter of the second shaft hole 27 in cooperation with the main body portion 64.

As shown in FIG. 13, the second moving body portion 81 is inserted into the engaging groove 77 by inserting the engaging protrusion 86 into the guide window 60 in a state of being engaged with the first moving body portion 71. Have been placed. By assembling the first moving body portion 71 and the second moving body portion 81 in this way, the first moving body portion 71 and the second moving body portion 81 are integrated in the axial direction of the drive shaft 47. It is possible to move to. The moving body passage 82 of the second moving body portion 81 communicates with the axis 57.

An urging spring 88 is housed in the large-diameter road 61. One end of the urging spring 88 is supported by the stepped surface 63. The other end of the urging spring 88 is supported by one end surface 72a of the first main body 72. The urging spring 88 urges the first main body 72 toward the control pressure chamber 46 against the control pressure of the control pressure chamber 46.

As shown in FIGS. 4 and 5, the rotation of the drive shaft 47 is transmitted to the second moving body portion 81 via the guide surface 67. As a result, the second moving body portion 81 can rotate integrally with the drive shaft 47. At this time, since the engaging groove 77 and the engaging protrusion 86 are engaged, the first moving body portion 71 rotates independently of the second moving body portion 81 in the axis 57. Is regulated. Therefore, the moving body 70 is provided on the drive shaft 47 and rotates integrally with the drive shaft 47. Then, as the drive shaft 47 rotates, the moving body 70 rotates integrally with the drive shaft 47, so that the moving body passage 82 intermittently communicates with the rear side passages 29a, 29b, 29c, 29d, and 29e. .. Therefore, the moving body passage 82 is a second passage that intermittently communicates with the rear side passages 29a, 29b, 29c, 29d, and 29e as the drive shaft 47 rotates. Further, as shown in FIG. 3, the rotation of the drive shaft 47 causes the second path 59 to intermittently communicate with the front side passages 21a, 21b, 21c, 21d, and 21e.

As shown in FIGS. 1 and 2, the piston type compressor 10 includes a control valve 89. The control valve 89 is provided in the rear housing 15. Further, the piston type compressor 10 includes a detection passage 90 that connects the swash plate chamber 32 and the control valve 89. The detection passage 90 penetrates the rear housing 15 and the second cylinder block 13. Further, the rear housing 15 is formed with a first air supply passage 91 and a second air supply passage 92. The first air supply passage 91 connects the second discharge chamber 42 and the control valve 89. The second air supply passage 92 connects the control pressure chamber 46 and the control valve 89.

A part of the refrigerant gas in the second discharge chamber 42 is introduced into the control pressure chamber 46 via the first air supply passage 91, the control valve 89, and the second air supply passage 92. Further, the control pressure chamber 46 is connected to the swash plate chamber 32 by an air extraction passage (not shown). As a result, the refrigerant gas in the control pressure chamber 46 is discharged to the swash plate chamber 32 via the bleed air passage.

The control valve 89 adjusts the valve opening degree by sensing the suction pressure, which is the pressure of the refrigerant gas in the swash plate chamber 32, through the detection passage 90. As a result, the control valve 89 adjusts the flow rate of the refrigerant gas introduced from the second discharge chamber 42 into the control pressure chamber 46 via the first air supply passage 91, the control valve 89, and the second air supply passage 92. .. When the valve opening degree of the control valve 89 becomes large, the flow rate of the refrigerant gas introduced from the second discharge chamber 42 into the control pressure chamber 46 via the first air supply passage 91, the control valve 89, and the second air supply passage 92. Increases. Further, when the valve opening degree of the control valve 89 becomes smaller, the refrigerant gas introduced from the second discharge chamber 42 into the control pressure chamber 46 via the first air supply passage 91, the control valve 89, and the second air supply passage 92. Flow rate decreases. In this way, the control valve 89 changes the flow rate of the refrigerant gas introduced from the second discharge chamber 42 into the control pressure chamber 46 with respect to the flow rate of the refrigerant gas discharged from the control pressure chamber 46 to the swash plate chamber 32. This controls the control pressure, which is the pressure of the refrigerant gas in the control pressure chamber 46.

In FIGS. 3, 4, and 5, the rotation direction of the drive shaft 47 is indicated by an arrow R1. When the drive shaft 47 is at the rotation angle shown in FIGS. 3, 4, and 5, the first compression chamber 53a shown in FIG. 3 is in the initial stage of the re-expansion stroke or the suction stroke. Therefore, of the first compression chambers 53b and 53e adjacent to the first compression chamber 53a in the circumferential direction of the drive shaft 47, the first compression chamber 53b located on the trailing side in the rotation direction of the drive shaft 47 is the first. 1 The suction stroke is advanced from the compression chamber 53a, and the middle stage of the suction stroke is reached. Then, among the first compression chambers 53a and 53c adjacent to the first compression chamber 53b in the circumferential direction of the drive shaft 47, in the first compression chamber 53c located on the trailing side in the rotation direction of the drive shaft 47, the piston The first head 52a of 52 becomes the bottom dead center, and the state shifts from the suction stroke to the compression stroke. Therefore, the first compression chamber 53c is in a state of shifting from the late stage of the suction stroke to the early stage of the compression stroke. Further, among the first compression chambers 53b and 53d adjacent to the first compression chamber 53c in the circumferential direction of the drive shaft 47, the first compression chamber 53d located on the trailing side in the rotation direction of the drive shaft 47 is the first. 1 The compression stroke is advanced from the compression chamber 53c, and the middle stage of the compression stroke is reached. Further, among the first compression chambers 53c and 53e adjacent to the first compression chamber 53d in the circumferential direction of the drive shaft 47, in the first compression chamber 53e located on the trailing side in the rotation direction of the drive shaft 47, the piston The first head 52a of 52 becomes the top dead center, and the state shifts from the latter stage of the compression stroke to the discharge stroke.

Here, the second path 59 is the front side passages 21a, 21b, 21c, 21d communicating with the first compression chambers 53a, 53b, 53c, 53d, 53e in the initial stage of the re-expansion stroke or the suction stroke. , 21e and communicate. Further, the second route 59 faces the front side passages 21a, 21b, 21c, 21d, 21e communicating with the first compression chambers 53a, 53b, 53c, 53d, 53e in the middle stage of the suction stroke.

Therefore, when the rotation angle of the drive shaft 47 is in the state shown in FIG. 3, the first compression chamber 53a is in the initial stage of the re-expansion stroke or the suction stroke, and the first compression chamber 53b is in the middle stage of the suction stroke. Therefore, the second route 59 faces the front side passages 21a and 21b. Then, when the drive shaft 47 rotates further than the position shown in FIG. 3, the second path 59 faces the front side passages 21a and 21e.

At this time, the first compression chamber 53e communicating with the front side passage 21e is in the initial stage of the re-expansion stroke or the suction stroke, and the first compression chamber 53a communicating with the front side passage 21a is the suction stroke. It is in the mid-term stage. In this way, the second path 59 communicates with the first compression chambers 53a, 53b, 53c, 53d, 53e in the initial stage of the re-expansion stroke or the suction stroke as the drive shaft 47 rotates. It faces the passages 21a, 21b, 21c, 21d, and 21e in that order. Further, the second path 59 has front side passages 21a, 21b, which communicate with the first compression chambers 53a, 53b, 53c, 53d, 53e in the middle stage of the suction stroke as the drive shaft 47 rotates. It faces 21c, 21d, and 21e in sequence.

When the first compression chambers 53a, 53b, 53c, 53d, 53e are in the suction stroke, the discharge stroke, etc. as shown in FIG. 3, the second compression chamber 54a shown in FIGS. 4 and 5 is in the middle stage of the compression stroke. It is in. Further, among the second compression chambers 54b and 54e adjacent to the second compression chamber 54a in the circumferential direction of the drive shaft 47, the second compression chamber 54b located on the trailing side in the rotation direction of the drive shaft 47 has a second compression chamber. 2 The compression stroke is advanced from the compression chamber 54a, which is the latter stage of the compression stroke. Then, among the second compression chambers 54a and 54c adjacent to the second compression chamber 54b in the circumferential direction of the drive shaft 47, the second compression chamber 54c located on the trailing side in the rotation direction of the drive shaft 47 has a piston. The second head 52b of 52 becomes the top dead center, and the state shifts from the discharge stroke to the re-expansion stroke or the initial stage of the suction stroke. Further, among the second compression chambers 54b and 54d adjacent to the second compression chamber 54c in the circumferential direction of the drive shaft 47, the second compression chamber 54d located on the trailing side in the rotation direction of the drive shaft 47 has a second compression chamber. 2 The suction stroke is more advanced than the compression chamber 54c, and the middle stage of the suction stroke is reached. Then, among the second compression chambers 54c and 54e adjacent to the second compression chamber 54d in the circumferential direction of the drive shaft 47, the second compression chamber 54e located on the trailing side in the rotation direction of the drive shaft 47 is the second. 2 The suction stroke is further advanced than that of the compression chamber 54d, which is the latter stage of the suction stroke. That is, among the second compression chambers 54a, 54b, 54c, 54d, 54e, the second compression chambers 54a, 54b are in a high pressure state, and among the second compression chambers 54a, 54b, 54c, 54d, 54e, Each of the second compression chambers 54c, 54d, 54e is in a low pressure state.

Here, by providing the second moving body portion 81 in the guide window 60, the second moving body portion 81 has the second compression chambers 54a, 54b, 54c, 54d, which are in the re-expansion stroke or the suction stroke, respectively. It faces the rear side passages 29a, 29b, 29c, 29d, and 29e that communicate with 54e. Therefore, when the drive shaft 47 is at the rotation angle shown in FIGS. 4 and 5, the second moving body portion 81 communicates with the rear side communication passage 29c communicating with the second compression chamber 54c and the second compression chamber 54d. It faces the rear side communication passage 29d and the rear side communication passage 29e communicating with the second compression chamber 54e.

On the other hand, the main body 64 of the drive shaft 47 is connected to the rear side passages 29a, 29b, 29c, 29d, 29e communicating with the second compression chambers 54a, 54b, 54c, 54d, 54e in the compression stroke or the discharge stroke. Facing. Therefore, when the drive shaft 47 is at the rotation angle shown in FIGS. 4 and 5, the main body 64 has a rear side passage 29a communicating with the second compression chamber 54a and a rear side communication communicating with the second compression chamber 54b. Facing the passage 29b.

The second moving body portion 81 communicates with the second compression chambers 54a, 54b, 54c, 54d, 54e in the re-expansion stroke or the suction stroke as the drive shaft 47 rotates. It faces 29b, 29c, 29d, and 29e in sequence. Further, the main body 64 has rear side passages 29a, 29b, which communicate with the second compression chambers 54a, 54b, 54c, 54d, 54e in the compression stroke or the discharge stroke as the drive shaft 47 rotates. It faces 29c, 29d, and 29e in sequence.

Here, the end face of the main body 64 located on the trailing side of the drive shaft 47 in the rotational direction is the rear side communication passage 29c communicating with the second compression chamber 54c in the re-expansion stroke or the suction stroke, and the compression stroke. It is located between the rear side communication passage 29b communicating with the second compression chamber 54b, which is a later stage. Then, the main body 64 has a rear side communication passage 29c communicating with the second compression chamber 54c in the re-expansion stroke or the suction stroke, and a rear side communication passage communicating with the second compression chamber 54b which is a later stage of the compression stroke. It is formed so as to extend from between 29b and the inner peripheral surface of the shaft hole 48 in the circumferential direction of the drive shaft 47 more than half the circumference. The end faces of the main body 64 located on the leading side in the rotation direction of the drive shaft 47 are a rear side passage 29a communicating with the second compression chamber 54a, which is the middle stage of the compression stroke, and a second, which is the latter stage of the suction stroke. It is located beyond the distance from the rear side passage 29e that communicates with the compression chamber 54e. In the present embodiment, the end surface of the main body 64 located on the leading side in the rotation direction of the drive shaft 47 faces the rear side communication passage 29e communicating with the second compression chamber 54e, which is the latter stage of the suction stroke.

Next, the operation of this embodiment will be described.
In the piston type compressor 10 of the present embodiment, the rear side passages 29a, 29b, 29c, 29d, 29e per one rotation of the drive shaft 47, depending on the position of the second moving body portion 81 in the guide window 60. The area of communication between the vehicle and the moving body passage 82 changes. Further, the communication area between the second path 59 and the axis 57 changes according to the position of the suction valve body 74 in the small path 62, and the front side communication passages 21a, 21b, per rotation of the drive shaft 47, The communication area between the 21c, 21d, 21e and the second route 59 changes.

For example, when the valve opening degree of the control valve 89 is reduced, the flow rate of the refrigerant gas introduced from the second discharge chamber 42 into the control pressure chamber 46 decreases, and the control pressure and the suction pressure acting on the first main body 72 are reduced. The variable differential pressure, which is the differential pressure, becomes smaller. Then, the force obtained by adding the urging force of the urging spring 88 and the suction pressure acting on the one end surface 72a of the first main body 72 overcomes the control pressure acting on the other end surface of the first main body 72. 1 The moving body portion 71 moves toward the control pressure chamber 46. As a result, the pair of guide portions 85 of the second moving body portion 81 are guided by the pair of guide surfaces 67 in the guide window 60, and the second moving body portion 81 moves toward the first regulation surface 65. The moving body passage 82 moves relative to the rear side continuous passages 29a, 29b, 29c, 29d, 29e toward the first regulation surface 65. Therefore, the pair of guide surfaces 67 guide the second moving body portion 81. Therefore, the guide window 60 guides the moving body 70 in the axial direction of the drive shaft 47.

Then, the moving body passage 82 moves relative to the rear side passages 29a, 29b, 29c, 29d, 29e toward the first regulation surface 65, so that the rear side passages 29a, 29b, 29c, The 29d and 29e communicate with the moving body passage 82 near the small opening 84 in the moving body passage 82. As a result, the communication area between the rear side passages 29a, 29b, 29c, 29d, 29e and the moving body passage 82 per rotation of the drive shaft 47 is gradually reduced.

Further, as the first moving body portion 71 moves toward the control pressure chamber 46, the suction valve body 74 moves in the small path 62 of the shaft path 57 toward the large path 61. As a result, the suction valve body 74 begins to close the second path 59 in the small path 62, and the communication area between the axis 57 and the second path 59 gradually decreases.

Then, when the valve opening degree of the control valve 89 is further reduced and the control pressure of the control pressure chamber 46 is further reduced, the variable differential pressure is minimized. As a result, as shown in FIG. 9, the first moving body portion 71 is in a state of being moved toward the control pressure chamber 46 most in the large-diameter path 61. As a result, the second moving body portion 81 is in a state of moving most toward the first regulation surface 65 in the guide window 60, and the first curved portion 81a of the second moving body portion 81 comes into contact with the first regulation surface 65. .. The contact between the first curved portion 81a of the second moving body portion 81 and the first regulating surface 65 restricts the movement of the first moving body portion 71 toward the control pressure chamber 46. As a result, the rear side passages 29a, 29b, 29c, 29d, 29e communicate with the small opening 84 in the moving body passage 82, and the rear side passages 29a, 29b, 29c per rotation of the drive shaft 47. , 29d, 29e and the moving body passage 82 have the minimum communication area.

When the drive shaft 47 is at the rotation angle shown in FIG. 4, for example, in a state where the first curved portion 81a of the second moving body portion 81 and the first regulating surface 65 are in contact with each other, the second moving body portion 81 , The rear side communication passage 29c and the moving body passage 82 are communicated with each other. At this time, the second compression chamber 54c through which the rear side communication passage 29c communicates is in a state of shifting from the discharge stroke to the re-expansion stroke or the initial stage of the suction stroke. Further, the second moving body portion 81 has a rear side continuous passage 29d due to the outer surface of the second curved portion 81b.
The 29e and the mobile passage 82 are not communicated with each other. That is, the second moving body portion 81 communicates with the second compression chambers 54a, 54b, 54c, 54d, 54e in the initial stage of the re-expansion stroke or the suction stroke, respectively. Only 29d and 29e communicate with the moving body passage 82.

Further, the main body 64 of the drive shaft 47 is connected to the rear side passages 29a, 29b, 29c, 29d, 29e communicating with the second compression chambers 54a, 54b, 54c, 54d, 54e in the compression stroke or the discharge stroke. Facing. As a result, the main body 64 of the drive shaft 47 is connected to the rear side passages 29a, 29b, 29c, 29d, which communicate with the second compression chambers 54a, 54b, 54c, 54d, 54e in the compression stroke or the discharge stroke. The 29e and the moving body passage 82 are not communicated with each other.

As described above, when the variable differential pressure is the minimum, each of the second compression chambers 54a, 54b, 54c, 54d, 54e has the swash plate chamber 32 to the swash plate suction hole 56, only when it is in the initial stage of the suction stroke. Refrigerant gas is sucked through the first path 58, the axis 57, the moving body passage 82, and the rear side connecting passages 29a, 29b, 29c, 29d, 29e. As a result, the flow rate of the refrigerant gas sucked from the swash plate chamber 32 into the second compression chambers 54a, 54b, 54c, 54d, 54e becomes the smallest, and the flow rates of the refrigerant gas sucked from the second compression chambers 54a, 54b, 54c, 54d, 54e become the smallest. 2 The flow rate of the refrigerant gas discharged to the discharge chamber 42 is minimized.

At this time, with the rotation of the drive shaft 47, at the timing before the moving body passage 82 faces the rear side passages 29a, 29b, 29c, 29d, 29e, the stepped portion 87 has the rear side passages 29a, It faces 29b, 29c, 29d, 29e. The space between the inner peripheral surface of the shaft hole 48 and the stepped portion 87 functions as a flow path for guiding the refrigerant gas from the moving body passage 82 to the rear side continuous passages 29a, 29b, 29c, 29d, 29e. Therefore, as the suction of the refrigerant gas from the moving body passage 82 into the rear side connecting passages 29a, 29b, 29c, 29d, 29e becomes accompanied by the rotation of the drive shaft 47, the moving body passage 82 becomes each rear side connecting passage 29a. , 29b, 29c, 29d, 29e, and the timing before facing each other.

Further, the variable differential pressure is minimized, and the first moving body portion 71 moves in the large diameter path 61 toward the control pressure chamber 46 most, so that the suction valve body 74 has the small diameter path 62 as shown in FIG. The second route 59 is closed inside. As a result, the communication area between the axial path 57 and the second path 59 becomes the minimum, that is, almost zero. As a result, when the variable differential pressure is the minimum, the flow rate of the refrigerant gas sucked from the swash plate chamber 32 into each of the first compression chambers 53a, 53b, 53c, 53d, 53e becomes almost zero, and each of the first compression chambers 53a, The flow rate of the refrigerant gas discharged from the 53b, 53c, 53d, 53e to the first discharge chamber 36 becomes almost zero. Therefore, when the variable differential pressure is the minimum, each of the first compression chambers 53a, 53b, 53c, 53d, 53e is in a cylinder deactivation state in which suction work or compression work is not performed. As described above, the refrigerant discharged from each of the first compression chambers 53a, 53b, 53c, 53d, 53e and each of the second compression chambers 54a, 54b, 54c, 54d, 54e to the first discharge chamber 36 and the second discharge chamber 42, respectively. The gas flow rate decreases.

For example, when the valve opening degree of the control valve 89 is increased, the flow rate of the refrigerant gas introduced from the second discharge chamber 42 into the control pressure chamber 46 increases, and the variable differential pressure increases. Then, the control pressure acting on the other end surface of the first main body 72 overcomes the sum of the urging force of the urging spring 88 and the suction pressure acting on the one end surface 72a of the first main body 72. The first moving body portion 71 moves toward the side opposite to the control pressure chamber 46. As a result, the pair of guide portions 85 of the second moving body portion 81 are guided by the pair of guide surfaces 67 in the guide window 60, and the second moving body portion 81 moves toward the second regulation surface 66. The mobile passage 82 moves relative to each of the rear side passages 29a, 29b, 29c, 29d, 29e toward the second regulation surface 66. Therefore, the first moving body portion 71 moves in the axial path 57 in the axial direction of the drive shaft 47 based on the control pressure. Therefore, the moving body 70
It is movable with respect to the drive shaft 47 in the axial direction of the drive shaft 47 based on the control pressure.

Then, the moving body passage 82 moves relative to the rear side passages 29a, 29b, 29c, 29d, 29e toward the second regulation surface 66, so that the rear side passages 29a, 29b, 29c, The 29d and 29e communicate with the moving body passage 82 near the large opening 83 in the moving body passage 82. As a result, the communication area between the rear side passages 29a, 29b, 29c, 29d, 29e and the moving body passage 82 per rotation of the drive shaft 47 gradually increases.

Further, as the first moving body portion 71 moves toward the side opposite to the control pressure chamber 46, the suction valve body 74 directs the inside of the small path 62 of the shaft path 57 toward the side opposite to the large path 61. Moving. Then, in the small path 62, the suction valve body 74 starts to open the second path 59, the communication area between the axis 57 and the second path 59 gradually increases, and the front side communication passages 21a, 21b, 21c, The communication area between the 21d and 21e and the second path 59 becomes larger than zero. As a result, for each of the first compression chambers 53a, 53b, 53c, 53d, 53e in the initial stage of the suction stroke and the middle stage of the suction stroke, the swash plate chamber 32 to the swash plate suction hole 56, the first path 58, and the axial path. Refrigerant gas is sucked through 57, the second path 59, and the front side passages 21a, 21b, 21c, 21d, 21e. As a result, suction work and compression work are performed in the first compression chambers 53a, 53b, 53c, 53d, 53e, and the first compression chambers 53a, 53b, 53c, 53d, 53e discharge to the first discharge chamber 36. The flow rate of the refrigerant gas to be generated increases.

Then, when the valve opening degree of the control valve 89 is further increased and the control pressure of the control pressure chamber 46 is further increased, the variable differential pressure becomes maximum. As a result, as shown in FIG. 10, the first moving body portion 71 is in a state of being moved toward the side most opposite to the control pressure chamber 46 in the large-diameter path 61. As a result, the second moving body portion 81 is in a state of moving most toward the second regulating surface 66 in the guide window 60, and the second curved portion 81b of the second moving body portion 81 comes into contact with the second regulating surface 66. .. The contact between the second curved portion 81b of the second moving body portion 81 and the second regulating surface 66 restricts the movement of the first moving body portion 71 toward the side opposite to the control pressure chamber 46. As a result, the rear side passages 29a, 29b, 29c, 29d, 29e communicate with the large opening 83 in the moving body passage 82, and the rear side passages 29a, 29b, 29c per rotation of the drive shaft 47. , 29d, 29e and the moving body passage 82 have the maximum communication area.

When the drive shaft 47 is at the rotation angle shown in FIG. 5, for example, in a state where the second curved portion 81b of the second moving body portion 81 and the second regulating surface 66 are in contact with each other, the second moving body portion 81 , Each of the rear side passages 29c, 29d, 29e and the moving body passage 82 are communicated with each other. That is, the second moving body portion 81 communicates with the second compression chambers 54a, 54b, 54c, 54d, 54e in the initial stage of the re-expansion stroke or the suction stroke, respectively. The 29d and 29e are communicated with the moving body passage 82. Further, the second moving body portion 81 includes the rear side passages 29a, 29b, 29c, 29d, 29e communicating with the second compression chambers 54a, 54b, 54c, 54d, 54e in the middle stage of the suction stroke. Communicate with the moving body passage 82. Further, the second moving body portion 81 includes the rear side passages 29a, 29b, 29c, 29d, 29e communicating with the second compression chambers 54a, 54b, 54c, 54d, 54e in the latter stage of the suction stroke. Communicate with the moving body passage 82. Therefore, the moving body 70 communicates with the rear side passages 29a, 29b, 29c, 29d, 29e communicating with the second compression chambers 54a, 54b, 54c, 54d, 54e and the moving body passage 82.

Further, the main body 64 of the drive shaft 47 is connected to the rear side passages 29a, 29b, 29c, 29d, 29e communicating with the second compression chambers 54a, 54b, 54c, 54d, 54e in the compression stroke or the discharge stroke. Facing. Therefore, the rear side communication passages 29a, 29b, 29c, 29d, 29e communicating with the second compression chambers 54a, 54b, 54c, 54d, 54e by the drive shaft 47 and the moving body passage 82 are not communicated with each other.

In this way, by maximizing the variable differential pressure, the refrigerant gas in the swash plate chamber 32 is provided in each of the second compression chambers 54a, 54b, 54c, 54d, 54e from the initial stage to the late stage of the suction stroke. Is inhaled. Therefore, the flow rate of the refrigerant gas sucked into the second compression chambers 54a, 54b, 54c, 54d, 54e increases, and the second discharge chambers 42 from the second compression chambers 54a, 54b, 54c, 54d, 54e The flow rate of the refrigerant gas discharged to is maximized.

Further, the variable differential pressure is maximized, and the first moving body portion 71 moves in the large-diameter path 61 toward the side most opposite to the control pressure chamber 46, so that the suction valve body 74 becomes as shown in FIG. , The opening degree of the second path 59 is maximized in the small path 62. As a result, the communication area between the axis 57 and the second route 59 is maximized, and the communication area between the front side communication passages 21a, 21b, 21c, 21d, 21e and the second route 59 is maximized. As a result, the flow rate of the refrigerant gas sucked into each of the first compression chambers 53a, 53b, 53c, 53d, 53e becomes maximum, so that the first discharge from each of the first compression chambers 53a, 53b, 53c, 53d, 53e The flow rate of the refrigerant gas discharged into the chamber 36 is maximized.

As described above, in the piston type compressor 10 of the present embodiment, the first compression chambers 53a, 53b, 53c, 53d, 53e and the second compression chambers 53a, 53b, 53c, 53d, 53e are provided according to the position of the drive shaft 47 of the moving body 70 in the axial direction. The flow rate of the refrigerant gas discharged from each of the compression chambers 54a, 54b, 54c, 54d, 54e to the first discharge chamber 36 and the second discharge chamber 42 changes.

For example, it was compressed in the compression stroke through the rear side communication passages 29a, 29b, 29c, 29d, 29e communicating with the second compression chambers 54a, 54b, 54c, 54d, 54e in the compression stroke or the discharge stroke. A part of the high-pressure refrigerant gas flows into the second shaft hole 27. At this time, in the second shaft hole 27, the rear side communication passages 29a in which the main body 64 of the drive shaft 47 communicates with the second compression chambers 54a, 54b, 54c, 54d, 54e in the compression stroke or the discharge stroke. , 29b, 29c, 29d, 29e. As a result, the main body 64 moves to the rear side passages 29a, 29b, 29c, 29d, 29e communicating with the second compression chambers 54a, 54b, 54c, 54d, 54e in the compression stroke or the discharge stroke. The body passage 82 is not communicated with the body passage 82. Since the drive shaft 47 is made of steel, the drive shaft 47 receives the compression load from the second compression chambers 54a, 54b, 54c, 54d, 54e in the compression stroke and the discharge stroke. Therefore, it becomes difficult for a compressive load to act on the second moving body portion 81. Therefore, the moving body 70 can easily move in the axial direction of the drive shaft 47.

Further, it is compressed in the compression stroke via the front side communication passages 21a, 21b, 21c, 21d, 21e communicating with the first compression chambers 53a, 53b, 53c, 53d, 53e in the compression stroke or the discharge stroke. A part of the high-pressure refrigerant gas flows into the first shaft hole 19. Also at this time, the drive shaft 47 receives the compressive load from the first compression chambers 53a, 53b, 53c, 53d, 53e in the compression stroke and the discharge stroke. Therefore, it is difficult for a compressive load to act on the suction valve body 74.

In the above embodiment, the following effects can be obtained.
(1) In the second moving body portion 81, the first moving body portion 71 moves in the axial path 57 in the axial direction of the drive shaft 47 based on the control pressure, so that the first moving body portion 81 has the first moving body portion 60 in the guide window 60. It moves integrally with the unit 71 in the axial direction of the drive shaft 47. Then, depending on the position of the drive shaft 47 in the second moving body portion 81 in the axial direction, the rear side passages 29a, 29b, 29c, 29d, 29e and the moving body passage 82 are arranged per rotation of the drive shaft 47. The communication angle around the axis of communication changes. As a result, the flow rate of the refrigerant gas discharged from each of the second compression chambers 54a, 54b, 54c, 54d, 54e to the second discharge chamber 42 changes.

Here, the second moving body portion 81 has a curved plate shape extending along the inner peripheral surface of the shaft hole 48, and in order to secure the rigidity of the second moving body portion 81, for example, in a pair of guide portions 85. It is conceivable to increase the width of the second moving body portion 81 in the circumferential direction. However, since the width of the second moving body portion 81 in the pair of guide portions 85 in the circumferential direction is increased, the width of the second moving body portion 81 in the moving body passage 82 in the circumferential direction is reduced, so that the moving body passage 82 The flow path area becomes smaller. As a result, it becomes difficult for the refrigerant gas to be sucked into the rear side passages 29a, 29b, 29c, 29d, and 29e from the moving body passage 82, and the controllability may be deteriorated.

Therefore, since one of the pair of guide portions 85 has a stepped portion 87 that is continuous with the moving body passage 82 and is recessed in a direction away from the inner peripheral surface of the shaft hole 48, the inner circumference of the shaft hole 48 is formed. It can function as a flow path for guiding the refrigerant gas from the moving body passage 82 to the rear side continuous passages 29a, 29b, 29c, 29d, 29e between the surface and the step portion 87. Therefore, in order to secure the rigidity of the second moving body portion 81, even if the width of the second moving body portion 81 in the pair of guide portions 85 in the circumferential direction is increased, each rear side continuous passage from the moving body passage 82 It is suppressed that the inhalation of the refrigerant gas into the 29a, 29b, 29c, 29d, and 29e becomes difficult.

Then, the rear side passages 29a, 29b, 29c, 29d, 29e and the moving body passage 82 are not communicated with each other by the drive shaft 47, and the piston 52 moves from the bottom dead center to the top dead center. The second compression chambers 54a, 54b, 54c, 54d, 54e serve as a compression stroke or a discharge stroke. As a result, the drive shaft 47 receives a compression load, which is a load due to the high-pressure refrigerant gas compressed in each of the second compression chambers 54a, 54b, 54c, 54d, 54e, in the rear side communication passages 29a, 29b, 29c. While acting via 29d and 29e, it becomes difficult for a compressive load to act on the moving body 70. Therefore, since the moving body 70 can easily move in the axial direction of the drive shaft 47, it is not necessary to make the moving body 70 larger than necessary in order to obtain a large thrust. Therefore, it is possible to exhibit high controllability and realize miniaturization.

(2) For example, when the drive shaft 47 has the rotation angles shown in FIGS. 4 and 5, the main body 64 has a rear side passage 29c communicating with the second compression chamber 54c in the re-expansion stroke or the suction stroke. It is formed so as to extend more than half a circumference in the circumferential direction of the drive shaft 47 along the inner peripheral surface of the shaft hole 48 from between the rear side communication passage 29b communicating with the second compression chamber 54b, which is the latter stage of the compression stroke. ing. According to this, as the drive shaft 47 rotates, the boundary between the main body portion 64 and the second moving body portion 81 in the circumferential direction of the drive shaft 47 becomes the latter stage of the compression stroke, respectively. It is no longer facing the rear side communication passages 29a, 29b, 29c, 29d, 29e communicating with the 54b, 54c, 54d, 54e. Therefore, even if a backflow of the refrigerant gas occurs from each of the second compression chambers 54a, 54b, 54c, 54d, 54e, which is the latter stage of the compression stroke, toward the rear side passages 29a, 29b, 29c, 29d, 29e. It is possible to prevent the refrigerant gas from leaking to the shaft path 57 through the boundary between the main body portion 64 and the second moving body portion 81 in the circumferential direction of the drive shaft 47.

Therefore, it is suppressed that the compression pressure in each of the second compression chambers 54a, 54b, 54c, 54d, 54e, which is the latter stage of the compression stroke, is suppressed, so that the second cylinder bores 28a, 28b, 28c, 28d are suppressed. , The movement of the second head 52b of each piston 52 that reciprocates in 28e from the top dead center to the bottom dead center is facilitated. As a result, the power consumed by the piston type compressor 10 can be suppressed. Further, since the leakage of the high-temperature refrigerant gas to the shaft path 57 is suppressed, the deterioration of the compression performance of the piston type compressor 10 can be suppressed.

(3) Of the pair of guide portions 85, the guide portion 85 located on the leading side in the rotation direction of the drive shaft 47 has a step portion 87. According to this, as the drive shaft 47 rotates, the stepped portion 87 moves to each rear side passage before the moving body passage 82 faces each rear side passage 29a, 29b, 29c, 29d, 29e. It faces 29a, 29b, 29c, 29d, 29e.
Therefore, for example, in order to secure the rigidity of the second moving body portion 81, even if the width of the second moving body portion 81 in the pair of guide portions 85 in the circumferential direction is increased, each rear side from the moving body passage 82 It is possible to avoid delaying the intake timing of the refrigerant gas into the communication passages 29a, 29b, 29c, 29d, 29e.

(4) When the main body portion 64 is formed so as to extend more than half the circumference in the circumferential direction of the drive shaft 47 along the inner peripheral surface of the shaft hole 48, the second moving body portion 81 is formed around the drive shaft 47. It will be formed smaller than half a circumference in the direction. Therefore, when trying to secure the opening area of the moving body passage 82, the width of the second moving body portion 81 in the pair of guide portions 85 in the circumferential direction may become small, and the rigidity of the second moving body portion 81 may decrease. .. Therefore, in the present embodiment, one of the pair of guide portions 85 has a step portion 87 that is continuous with the moving body passage 82 and is recessed in a direction away from the inner peripheral surface of the shaft hole 48. It can function as a flow path for guiding the refrigerant gas from the moving body passage 82 to the rear side communication passages 29a, 29b, 29c, 29d, 29e between the inner peripheral surface of the hole 48 and the step portion 87. Therefore, in order to secure the rigidity of the second moving body portion 81, it is possible to increase the width of the second moving body portion 81 in the circumferential direction of the pair of guide portions 85.

(5) Since the main body 64 is formed so as to extend more than half the circumference in the circumferential direction of the drive shaft 47 along the inner peripheral surface of the shaft hole 48, for example, the main body 64 is formed on the inner circumference of the shaft hole 48. The rigidity of the main body 64 can be increased as compared with the case where the drive shaft 47 is formed so as to extend smaller than half a circumference in the circumferential direction of the drive shaft 47 along the surface. Therefore, in the main body 64, it becomes easy to secure the rigidity that can withstand the compression load from each of the second compression chambers 54a, 54b, 54c, 54d, 54e in the compression stroke and the discharge stroke.

(6) The engaging groove 77 used for engaging the second moving body portion 81 with the first moving body portion 71 is formed at a position facing the guide window 60 in the first moving body portion 71, and is engaged. The engaging protrusion 86 that engages with the joint groove 77 is a flat plate that protrudes from the inner peripheral edge 82a of the moving body passage 82 in the second moving body portion 81 and is bent toward the inside of the guide window 60. According to this, since the engaging protrusion 86 does not project outward from the second moving body portion 81, the second moving body portion 81 can be made compact, and the piston type compressor 10 can be downsized. Contribute.

(7) The engaging protrusion 86 projects from the edge of the moving body passage 82 formed by the first curved portion 81a of the second moving body portion 81. According to this, for example, as compared with the configuration in which the engaging protrusion 86 protruding from the edge of the moving body passage 82 formed by the second curved portion 81b is engaged with the engaging groove 77, the second moving body The portion 81 is less likely to tilt with respect to the axial direction of the drive shaft 47. Therefore, it is possible to prevent the second moving body portion 81 from moving in the axial direction of the drive shaft 47 in a state of being tilted with respect to the axial direction of the drive shaft 47.

(8) The engaging protrusion 86 projects from the central portion of the second moving body portion 81 in the circumferential direction at the edge of the moving body passage 82 formed by the first curved portion 81a of the second moving body portion 81. .. According to this, for example, the engaging protrusion 86 projects from a position deviated from the central portion in the circumferential direction of the second moving body portion 81 at the edge portion of the moving body passage 82 formed by the first curved portion 81a. Compared to the case where the second moving body portion 81 is used, the second moving body portion 81 is less likely to be tilted with respect to the axial direction of the drive shaft 47. Therefore, it is possible to prevent the second moving body portion 81 from moving in the axial direction of the drive shaft 47 in a state of being tilted with respect to the axial direction of the drive shaft 47.

The above embodiment can be modified and implemented as follows. The above embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

○ As shown in FIG. 16, the second moving body portion 81 has a configuration in which one of the pair of guide portions 85 has an elongated thin plate-shaped bent portion 93 that is bent toward the other of the pair of guide portions 85. You may. The bent portion 93 forms one part of a pair of guide portions 85. The bent portion 93 is bent along one of the pair of guide surfaces 67. Then, a stepped portion 87 recessed in a direction away from the inner peripheral surface of the shaft hole 48 may be formed at an edge portion of the bent portion 93 located on the opposite side of the pair of guide portions 85. The step portion 87 is continuous with the moving body passage 82. The second moving body portion 81 may be further provided with a reinforcing rib 94 for reinforcing the second moving body portion 81. The reinforcing rib 94 is, for example, an elongated thin plate that connects the first curved portion 81a and the second curved portion 81b. According to this, the rigidity of the second moving body portion 81 can be further secured.

○ In the embodiment, by adjusting the distance of the step portion 87 from the inner peripheral surface of the shaft hole 48, the moving body passage 82 and each rear side connection are connected between the inner peripheral surface of the shaft hole 48 and the step portion 87. It may function as a diaphragm provided between the passages 29a, 29b, 29c, 29d, and 29e. According to this, it is possible to easily minimize the flow rate of the refrigerant gas discharged from each of the second compression chambers 54a, 54b, 54c, 54d, 54e to the second discharge chamber 42.

○ In the embodiment, the distance of the step portion 87 from the inner peripheral surface of the shaft hole 48 is set to a distance where the step portion 87 is not located on the guide surface 67 but is located inside the guide window 60. May be good. In short, the step portion 87 may not be guided by the guide surface 67. Therefore, one of the pair of guide portions 85 may be configured so that at least a part thereof is guided by one of the pair of guide surfaces 67.

○ In the embodiment, the other of the pair of guide portions 85 may also have a step portion 87. That is, of the pair of guide portions 85, the step portion 87 may also be formed on the guide portion located on the trailing side in the rotation direction of the drive shaft 47. In short, at least one of the pair of guide portions 85 may have a step portion 87.

○ In the embodiment, one of the pair of guide portions 85 may have a configuration in which, in addition to the portion closer to the small opening 84, the portion closer to the large opening 83 is also a step portion 87. That is, most of the pair of guide portions 85 may be step portions 87.

○ In the embodiment, the guide window 60 may extend over half a circumference in the circumferential direction of the drive shaft 47. That is, the main body 64 may be formed so as to extend over half a circumference in the circumferential direction of the drive shaft 47. In this case, the second moving body portion 81 is also in the shape of a curved plate formed so as to extend over half a circumference in the circumferential direction of the drive shaft 47.

○ In the embodiment, the guide window 60 may extend smaller than half a circumference in the circumferential direction of the drive shaft 47. That is, the main body 64 may be formed so as to extend smaller than half the circumference in the circumferential direction of the drive shaft 47. In this case, the second moving body portion 81 has a curved plate shape formed larger than a half circumference in the circumferential direction of the drive shaft 47.

○ In the embodiment, for example, an engaging hole having a long square hole shape in a plan view is formed on the outer peripheral surface of the first main body portion 72 of the first moving body portion 71, and the engaging protrusion 86 serves as an engaging hole. By being engaged, the second moving body portion 81 may be engaged with the first moving body portion 71.

◯ In the embodiment, for example, the engaging protrusion 86 may protrude from the edge of the moving body passage 82 formed by the second curved portion 81b. Further, for example, the engaging protrusions 86 may protrude from the edges of the moving body passage 82 formed by the pair of guide portions 85, respectively.

○ In the embodiment, for example, the engaging protrusion 86 projects from a position deviated from the central portion in the circumferential direction of the second moving body portion 81 at the edge portion of the moving body passage 82 formed by the first curved portion 81a. You may.

○ In the embodiment, for example, the engaging protrusion 86 may protrude from the edge of the first curved portion 81a opposite to the moving body passage 82.
○ In the embodiment, for example, the moving body 70 changes the flow rate of the refrigerant gas to be sucked from the swash plate chamber 32 into the first compression chambers 53a, 53b, 53c, 53d, 53e per rotation of the drive shaft 47. You may do so. Further, the suction valve body 74 may be configured to change the flow rate of the refrigerant gas sucked from the inside of the swash plate chamber 32 into the second compression chambers 54a, 54b, 54c, 54d, 54e per rotation of the drive shaft 47. ..

○ In the embodiment, the second route 59 is provided through the front side passages 21a, 21b, 21c, 21d, 21e, respectively, in the first compression chambers 53a, 53b in the initial stage of the suction stroke to the latter stage of the suction stroke. , 53c, 53d, 53e may be formed on the drive shaft 47 so that the refrigerant gas is sucked into the drive shaft 47. Further, the second route 59 is provided with a refrigerant only in the first compression chambers 53a, 53b, 53c, 53d, 53e in the initial stage of the suction stroke via the front side passages 21a, 21b, 21c, 21d, 21e. It may be formed on the drive shaft 47 so that the gas can be sucked.

○ In the embodiment, a suction chamber communicating with the suction port 22 is formed in the housing 11 separately from the swash plate chamber 32, and the first compression chambers 53a, 53b, 53c, 53d, 53e and the second compression chambers 54a, 54b are formed. , 54c, 54d, 54e may be configured such that the refrigerant gas in the suction chamber is sucked. In this case, the suction chamber needs to communicate with the axis 57.

○ In the embodiment, the moving body 70 performs a part of the refrigerant gas compressed in each of the second compression chambers 54a, 54b, 54c, 54d, 54e in the compression stroke in each second compression in the re-expansion stroke and the suction stroke. It may be configured to be distributed to the chambers 54a, 54b, 54c, 54d, 54e. With such a configuration, the flow rate of the refrigerant gas discharged from each of the second compression chambers 54a, 54b, 54c, 54d, 54e to the second discharge chamber 42 may be changed per rotation of the drive shaft 47. ..

○ In the embodiment, the control valve 89 may be an external control valve that controls the control pressure by switching ON and OFF of the external current, or controls the control pressure regardless of the external current. It may be an internal control valve. Here, when the control valve 89 is an external control valve, if the control valve 89 reduces the valve opening degree by turning off the current to the control valve 89, the piston type compressor 10 is stopped. , The valve opening degree becomes smaller, and the control pressure of the control pressure chamber 46 can be lowered. Therefore, the refrigerant gas discharged from the first compression chambers 53a, 53b, 53c, 53d, 53e and the second compression chambers 54a, 54b, 54c, 54d, 54e to the first discharge chamber 36 and the second discharge chamber 42. Since the piston type compressor 10 can be started in the state where the flow rate of the above is the minimum, the starting shock can be reduced.

○ In the embodiment, the control valve 89 may perform extraction side control for changing the flow rate of the refrigerant gas led out from the control pressure chamber 46 to the swash plate chamber 32 via the bleed air passage. In this case, the first compression chambers 53a, 53b, 53c, 53d, 53e and the second compression chambers 54a, 54b, 54c, 54d, 54e are discharged to the first discharge chamber 36 and the second discharge chamber 42. Since the amount of the refrigerant gas in the second discharge chamber 42 used when changing the flow rate of the refrigerant gas can be reduced, the efficiency of the piston type compressor 10 can be improved. Further, in this case, if the valve opening degree is increased by turning off the current to the control valve 89, the valve opening degree becomes large when the piston type compressor 10 is stopped, and the control pressure chamber 46 The control pressure can be lowered. Therefore, the refrigerant gas discharged from the first compression chambers 53a, 53b, 53c, 53d, 53e and the second compression chambers 54a, 54b, 54c, 54d, 54e to the first discharge chamber 36 and the second discharge chamber 42. Since the piston type compressor 10 can be started in the state where the flow rate of the above is the minimum, the start-up shock can be reduced.

○ In the embodiment, the control valve 89 may be a three-way valve whose opening degree can be adjusted by both the extraction passage and the air supply passage.
○ In the embodiment, the number of cylinder bores may be changed as appropriate.

O In the embodiment, the inner diameters of the first cylinder bores 20a, 20b, 20c, 20d, 20e and the inner diameters of the second cylinder bores 28a, 28b, 28c, 28d, 28e may be different.

○ In the embodiment, for example, the suction port 22 and the discharge port 24 may be formed with respect to the second cylinder block 13.
◯ In the embodiment, the first path 58 may have a shape that penetrates the drive shaft 47 in the radial direction.

○ In the embodiment, the shape of the second route 59 may be changed as appropriate.
○ In the embodiment, the piston type compressor 10 may be, for example, a single-headed piston type compressor in which the first compression chambers 53a, 53b, 53c, 53d, 53e are omitted.

○ In the embodiment, in the piston type compressor 10, the pulley and the electromagnetic clutch are not connected to the drive shaft 47, and the drive shaft 47 is connected to the engine of the vehicle via a constant power transmission type clutchless mechanism. It may have a configuration that is present.

○ In the embodiment, the mounting target of the piston type compressor 10 is not limited to the vehicle, but is arbitrary. Therefore, the piston type compressor 10 may be used in an air conditioner other than the vehicle.

10 ... Piston type compressor, 11 ... Housing, 13 ... Second cylinder block which is a cylinder block, 28a, 28b, 28c, 28d, 28e ... Second cylinder bore as a cylinder bore, 29a, 29b, 29c, 29d, 29e ... Rear side passage as a single passage, 32 ... a swash plate chamber functioning as a suction chamber, 42 ... a second discharge chamber as a discharge chamber, 44a ... a second discharge lead valve as a discharge valve, 47 ... a drive shaft, 48 ... Shaft hole, 50 ... Fixed sloping plate, 52 ... Piston, 54a, 54b, 54c, 54d, 54e ... Second compression chamber as compression chamber, 57 ... Axle path, 60 ... Guide window, 64 ... Main body, 67 ... Guide Surface, 70 ... moving body, 71 ... first moving body part, 81 ... second moving body part, 82 ... moving body passage which is a second continuous passage, 85 ... guide part, 87 ... stepped part, 89 ... control valve.

Claims (3)

A housing having a cylinder block in which a plurality of cylinder bores are formed, a suction chamber, a discharge chamber, a swash plate chamber, and a shaft hole.
A drive shaft rotatably supported in the shaft hole,
A fixed swash plate that can be rotated in the swash plate chamber by rotation of the drive shaft and has a constant inclination angle with respect to a plane perpendicular to the drive shaft.
A piston that forms a compression chamber in each cylinder bore and is connected to the fixed swash plate,
A discharge valve that discharges the refrigerant in the compression chamber to the discharge chamber,
A moving body provided on the drive shaft, which rotates integrally with the drive shaft and is movable with respect to the drive shaft in the axial direction of the drive shaft based on a control pressure.
A control valve for controlling the control pressure is provided.
The cylinder block is formed with a first communication passage that communicates with the cylinder bore.
The moving body is formed with a second passage that intermittently communicates with the first passage as the drive shaft rotates.
A piston type compressor in which the flow rate of the refrigerant discharged from the compression chamber to the discharge chamber changes according to the position of the moving body in the axial direction.
The drive shaft is located in an axial path that extends inside the drive shaft in the axial direction of the drive shaft and communicates with the suction chamber, and an axial path that communicates with the axial path and communicates with the shaft hole in the drive shaft. A guide window that opens on the outer peripheral surface of the portion and guides the moving body in the axial direction is formed.
The moving body communicates the first passage with the second passage, and the moving body communicates the first passage with the second passage.
The drive shaft makes the first communication passage and the second communication passage non-communication.
The moving body is
A first moving body portion that is located in the axial path and moves in the axial direction in the axial path based on the control pressure, and a first moving body portion.
It is arranged in the guide window in a state of being engaged with the first moving body portion, and has a curved plate shape extending along the inner peripheral surface of the shaft hole, and is formed in a state in which the second continuous passage penetrates. It has a second moving body part and
The guide window has a pair of guide surfaces that extend in the axial direction and guide the second moving body portion.
The second moving body portion forms both edges of the second continuous passage located on both sides of the second moving body portion in the circumferential direction, and at least a part thereof is guided by the pair of guide surfaces. Has a guide
A piston type compressor characterized in that at least one of the pair of guide portions has a stepped portion that is continuous with the second continuous passage and is recessed in a direction away from the inner peripheral surface of the shaft hole. .. The drive shaft is a portion located on the opposite side of the guide window with the axial center of the drive shaft, and is connected to the first communication passage communicating with the compression chamber during the compression stroke or the discharge stroke. It has a main body that faces it,
The main body is formed from between the first communication passage communicating with the compression chamber in the re-expansion stroke or the suction stroke and the first communication passage communicating with the compression chamber which is a later stage of the compression stroke. The piston type compressor according to claim 1, wherein the piston type compressor is formed so as to extend more than half a circumference in the circumferential direction of the drive shaft along the inner peripheral surface of the shaft hole. The piston-type compression according to claim 1 or 2, wherein the guide portion located on the leading side of the drive shaft in the rotation direction of the pair of guide portions has the step portion. Machine.