JP2019183837A - Piston compressor - Google Patents

Abstract

To provide a piston compressor capable of improving volumetric efficiency and attaining high controllability at the time of a low flow rate.SOLUTION: A compressor comprises a housing 1, a drive shaft 3, a fixed swash plate 5, a plurality of pistons 7, a valve forming plate 9 as a discharge valve, a rotor 11, and a control valve 13. In the compressor, a flow rate of refrigerant discharged from compression chambers 45a to 45f to a discharge chamber 29 varies depending on the position of the rotor 11 in an axis O direction. In the rotor 11, an energization chamber 43 is provided. The energization chamber 43 communicates with a control pressure chamber 37, and energizes the rotor 11 toward first communication passages 22a to 22f communicating with the compression chambers 45a to 45f during a compression stroke or a discharge stroke according to internal energization pressure.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a piston type compressor.

  Patent Documents 1 and 2 disclose conventional piston compressors (hereinafter simply referred to as compressors). The compressor described in Patent Document 1 includes a housing, a drive shaft, a fixed swash plate, a plurality of pistons, a discharge valve, a control valve, and a rotating body.

  The housing has a cylinder block. A plurality of cylinder bores are formed in the cylinder block, and a first communication path communicating with the cylinder bore is formed. In addition, a discharge chamber, a swash plate chamber, a shaft hole, and a control pressure chamber are formed in the housing. The refrigerant is sucked into the swash plate chamber from the outside of the compressor. The swash plate chamber communicates with the shaft hole.

  The drive shaft is rotatably supported in the shaft hole. 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 shaft. The piston forms a compression chamber in the cylinder bore and is connected to a fixed swash plate. A reed valve type discharge valve is provided between the compression chamber and the discharge chamber to discharge the refrigerant in the compression chamber to the discharge chamber. The control valve controls the pressure of the refrigerant to obtain a control pressure.

  The rotating body is provided on the outer peripheral surface of the drive shaft and is disposed in the shaft hole. Thereby, the rotating body partitions the suction chamber and the control pressure chamber. The rotating body rotates integrally with the drive shaft in the shaft hole and is movable relative to the drive shaft in the axial direction of the drive shaft based on the control pressure. A second communication path is formed on the outer peripheral surface of the rotating body. The second communication path intermittently communicates with the first communication path as the drive shaft rotates.

  In this compressor, each piston reciprocates in each cylinder bore, so that in the compression chamber, there are a suction stroke for sucking refrigerant, a compression stroke for compressing the sucked refrigerant, and a discharge stroke for discharging the compressed refrigerant. Done. The compressor can change the communication angle around the shaft center where the first communication path and the second communication path communicate with each other per rotation of the drive shaft according to the position of the rotating body in the axial direction. It is possible. Thereby, in this compressor, it is possible to change the flow rate of the refrigerant discharged from the compression chamber to the discharge chamber.

  Moreover, in the compressor of patent document 2, the connection member is provided in the rotary body. The connecting member is located between the drive shaft and the rotating body. A connecting recess is formed in the connecting member. Moreover, the connection convex part formed in the drive shaft has approached the inside of a connection member. Inside the connecting member, a coil spring is provided between the connecting concave portion and the connecting convex portion.

  In this compressor, the urging force of the coil spring acts on the rotating body through the connecting member, so that the rotating body is urged toward the first communication path in the shaft hole. Thereby, in this compressor, it is possible to make the gap generated between the first communication path and the rotating body as small as possible.

JP-A-5-306680 Japanese Patent Laid-Open No. 6-147110

  In this type of compressor, a load (hereinafter referred to as a compression load) due to a high-pressure refrigerant compressed in the compression chamber acts on the rotating body through the first communication passage communicating with the compression chamber during the compression stroke or during the compression stroke. To do. Thus, in the compressor described in Patent Document 1, the rotating body is pressed in a direction intersecting the axial direction in the shaft hole, so that the rotating body is pressed against the inner wall of the shaft hole, and the first reaming is performed. A gap between the passage and the rotating body is increased. For this reason, volume efficiency falls because the refrigerant | coolant compressed in the compression chamber becomes easy to leak from the clearance gap between a 1st communicating path and a rotary body.

  In this regard, in the compressor described in Patent Document 2, the rotating body is biased toward the first communication path by the coil spring so as to resist the compressive load, so that the compressive load acts on the rotating body. Leakage of refrigerant from the first communication path is suppressed. Therefore, it is conceivable to urge the rotating body with the urging force of the coil spring in the compressor described in Patent Document 1 as in the compressor described in Patent Document 2.

  However, the compression load acting on the rotating body increases as the flow rate of the refrigerant discharged from the compression chamber to the discharge chamber increases. For this reason, in order to suppress the leakage of the refrigerant from the first communication path at a high flow rate, it is necessary to increase the urging force of the coil spring so as to overcome the large compressive load acting on the rotating body. However, when the urging force is increased in this way, when the flow rate of the refrigerant discharged from the compression chamber to the discharge chamber is small and the compressive load acting on the rotator is small, the rotator is pivoted by the urging force of the coil spring. It will be in the state pressed too much against the inner wall of a hole. As a result, the frictional force between the rotating body and the shaft hole when the rotating body moves in the axial direction increases, and the rotating body becomes difficult to move suitably in the axial direction. descend.

  The present invention has been made in view of the above-described conventional situation, and it is an issue to be solved to provide a piston compressor capable of improving volumetric efficiency and realizing high controllability at a low flow rate. Yes.

The piston type compressor of the present invention has a cylinder block in which a plurality of cylinder bores are formed, a housing in which a discharge chamber, a swash plate chamber, and a shaft hole are formed,
A drive shaft rotatably supported in the shaft hole;
A fixed swash plate that is rotatable 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 the cylinder bore and is connected to the fixed swash plate;
A discharge valve for discharging the refrigerant in the compression chamber to the discharge chamber;
A rotating body provided on the drive shaft, rotating integrally with the drive shaft, and movable relative to the drive shaft in the axial direction of the drive shaft based on a control pressure;
The control pressure and a control valve for controlling,
The cylinder block is formed with a first communication path communicating with the cylinder bore,
The rotating body is formed with a second communication path that intermittently communicates with the first communication path 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 rotating body in the axial direction;
The rotating body moves in the axial direction so that the flow rate of the refrigerant discharged from the compression chamber to the discharge chamber increases as the control pressure increases,
At least one of the drive shaft and the rotating body communicates with the control pressure chamber, and the first communication communicates the rotating body with the compression chamber during a compression stroke or a discharge stroke by an internal biasing pressure. An urging chamber that urges toward the passage side is formed.

  In the piston compressor of the present invention, the urging pressure in the urging chamber urges the rotating body toward the first communication path that communicates with the compression chamber during the compression stroke or the discharge stroke. As a result, even when a compression load is applied to the rotating body, it is possible to suppress an increase in the gap between the first communication path and the rotating body, and the refrigerant compressed in the compression chamber is allowed to flow between the first communicating path and the rotating body. It is difficult to leak from the gap. Here, the compressive load acting on the rotating body increases as the flow rate of the refrigerant discharged from the compression chamber to the discharge chamber increases. In this regard, the rotating body moves in the axial direction of the drive shaft so that the flow rate of the refrigerant discharged from the compression chamber to the discharge chamber increases as the control pressure increases. That is, in this compressor, as the control pressure increases, the flow rate of the refrigerant discharged from each compression chamber to the discharge chamber increases. Here, since the urging chamber communicates with the control pressure chamber, the urging pressure increases as the control pressure increases. For this reason, in this compressor, the refrigerant compressed in the compression chamber hardly leaks from the gap between the first communication path and the rotating body even at a high flow rate.

  On the other hand, when the flow rate of the refrigerant discharged from each compression chamber to the discharge chamber is small, the control pressure is small, so the urging pressure is also small. For this reason, it is difficult for the biasing pressure to hinder the movement of the rotating body in the axial direction at a low flow rate.

  Therefore, the piston type compressor of the present invention can improve volumetric efficiency and can realize high controllability at a low flow rate.

  The urging chamber is recessed on the outer peripheral surface of the rotating body, and is preferably located on the opposite side of the first communication path communicating with the compression chamber during the compression stroke or the discharge stroke with the shaft center therebetween. .

  The urging chamber is preferably recessed on the outer peripheral surface of the drive shaft and is located on the same side with respect to the first communication passage communicating with the compression chamber during the compression stroke or the discharge stroke.

  In these cases, it is possible to favorably bias the rotating body with the biasing pressure while easily forming the biasing chamber in the rotating body or the drive shaft.

  The piston type compressor of the present invention can improve volumetric efficiency and can realize high controllability at low flow rate.

FIG. 1 is a cross-sectional view of the piston-type compressor according to the first embodiment at a minimum flow rate. FIG. 2 is a cross-sectional view of the piston type compressor according to the first embodiment at the maximum flow rate. FIG. 3 is an enlarged cross-sectional view of a main part showing the drive shaft, the rotating body, and the like at the minimum flow rate in the piston compressor of the first embodiment. FIG. 4 is an enlarged cross-sectional view of a main part showing a drive shaft, a rotating body, and the like at the maximum flow rate in the piston compressor of the first embodiment. FIG. 5 is an enlarged cross-sectional view of a main part showing the AA cross section of FIG. 3 according to the piston type compressor of the first embodiment. FIG. 6 is an enlarged cross-sectional view of a main part showing the BB cross section of FIG. 4 according to the piston compressor of the first embodiment. FIG. 7 is an enlarged cross-sectional view of a main part showing the CC cross section of FIG. 4 according to the piston compressor of the first embodiment. FIG. 8 is an enlarged cross-sectional view of a main part illustrating a drive shaft, a rotating body, and the like at the maximum flow rate in the piston compressor of the second embodiment. FIG. 9 is an enlarged cross-sectional view of a main part showing a DD cross section of FIG. 8 according to the piston compressor of the second embodiment.

  Embodiments 1 and 2 embodying the present invention will be described below with reference to the drawings. These compressors are single-head piston compressors. These compressors are mounted on a vehicle and constitute a refrigeration circuit of an air conditioner.

Example 1
As shown in FIGS. 1 and 2, the compressor of the first embodiment includes a housing 1, a drive shaft 3, a fixed swash plate 5, a plurality of pistons 7, a valve forming plate 9, a rotating body 11, A control valve 13 and a suction mechanism 15 are provided. The valve forming plate 9 is an example of the “discharge valve” in the present invention.

  The housing 1 includes a front housing 17, a rear housing 19, and a cylinder block 21. In the present embodiment, the front-rear direction of the compressor is defined with the side where the front housing 17 is located as the front side of the compressor and the side where the rear housing 19 is located as the rear side of the compressor. 1 and 2 is defined as the upper side of the compressor, and the lower side of the page is defined as the lower side of the compressor to define the vertical direction of the compressor. In FIG. 3 and subsequent figures, the front-rear direction and the vertical direction are displayed in correspondence with FIGS. In addition, the front-back direction in an Example is an example, and the attitude | position of the compressor of this invention is suitably changed according to the vehicle etc. which are mounted.

  The front housing 17 has a front wall 17a extending in the radial direction and a peripheral wall 17b that is integral with the front wall 17a and extends rearward from the front wall 17a in the direction of the axis O of the drive shaft 3, and is substantially cylindrical. It has a shape. A first boss portion 171, a second boss portion 172, and a first shaft hole 173 are formed in the front wall 17a. The first boss portion 171 protrudes forward in the direction of the axis O. A shaft seal device 25 is provided in the first boss portion 171. The second boss portion 172 protrudes rearward in the direction of the axis O in a swash plate chamber 31 described later. The first shaft hole 173 passes through the front wall 17a in the direction of the axis O.

  In the rear housing 19, a suction chamber 27, a discharge chamber 29, a suction port 27a, and a discharge port 29a are formed. The suction chamber 27 is located on the center side of the rear housing 19. The discharge chamber 29 is formed in an annular shape and is located on the outer peripheral side of the suction chamber 27. The suction port 27 a communicates with the suction chamber 27, extends in the rear housing 19 in the direction of the axis O, and opens to the outside of the rear housing 19. The suction port 27a is connected to the evaporator via a pipe. As a result, the low-pressure refrigerant gas that has passed through the evaporator is sucked into the suction chamber 27 through the suction port 27a. The discharge port 29 a communicates with the discharge chamber 29, extends in the radial direction of the rear housing 19, and opens to the outside of the rear housing 19. The discharge port 29a is connected to the condenser via a pipe. In addition, illustration of piping, an evaporator, and a condenser is abbreviate | omitted.

  The cylinder block 21 is located between the front housing 17 and the rear housing 19. The cylinder block 21 is joined to the front housing 17, thereby forming a swash plate chamber 31 between the front wall 17 a and the peripheral wall 17 b of the front housing 17. The swash plate chamber 31 communicates with the suction chamber 27 through a communication passage (not shown).

  As shown in FIGS. 5 to 7, cylinder bores 21 a to 21 f are formed in the cylinder block 21. The cylinder bores 21a to 21f are arranged at equiangular intervals in the circumferential direction. As shown in FIG.1 and FIG.2, each cylinder bore 21a-21f is each extended in the axial center O direction. The number of cylinder bores 21a to 21f can be designed as appropriate.

  The cylinder block 21 is formed with a second shaft hole 23, a support wall 24, and first communication passages 22a to 22f. The second shaft hole 23 is located on the center side of the cylinder block 21 and extends in the direction of the axis O. The rear side of the second shaft hole 23 is positioned in the suction chamber 27 by the cylinder block 21 being joined to the rear housing 19 via the valve forming plate 9. Thus, the second shaft hole 23 communicates with the suction chamber 27.

  The support wall 24 is located on the center side of the cylinder block 21 and in front of the second shaft hole 23. The second shaft hole 23 is partitioned from the swash plate chamber 31 by the support wall 24. A third shaft hole 240 is provided in the support wall 24. The third shaft hole 240 is coaxial with the first shaft hole 173 and penetrates the support wall 24 in the direction of the axis O. The first to third shaft holes 173, 23, and 240 are examples of the “shaft hole” in the present invention.

  As shown in FIGS. 5-7, the one end side of each 1st communicating path 22a-22f is each connected with each cylinder bore 21a-21f. Each of the first communication passages 22 a to 22 f extends in the radial direction of the cylinder block 21. Thereby, the other end side of each 1st communicating path 22a-22f is connected with the 2nd axial hole 23. FIG.

  As shown in FIGS. 1 and 2, the valve forming plate 9 is provided between the rear housing 19 and the cylinder block 21. The rear housing 19 and the cylinder block 21 are joined via the valve forming plate 9.

  The valve forming plate 9 includes a valve plate 91, a discharge valve plate 92, and a retainer plate 93. Six discharge holes 910 communicating with the cylinder bores 21a to 21f are formed in the valve plate 91. Each cylinder bore 21 a to 21 f communicates with the discharge chamber 29 through each discharge hole 910.

  The discharge valve plate 92 is provided on the rear surface of the valve plate 91. The discharge valve plate 92 is provided with six discharge leads 92a capable of opening and closing each discharge hole 910 by elastic deformation. The retainer plate 93 is provided on the rear surface of the discharge valve plate 92. The retainer plate 93 regulates the maximum opening of the discharge reed valve 92a.

  The drive shaft 3 extends from the front side of the housing 1 toward the rear side in the axis O direction. The drive shaft 3 has a screw portion 3a, a first diameter portion 3b, and a second diameter portion 3c. The threaded portion 3 a is located at the front end of the drive shaft 3. The drive shaft 3 is connected to a pulley, an electromagnetic clutch or the like (not shown) via the screw portion 3a.

  The first diameter portion 3b is continuous with the rear end of the screw portion 3a and extends in the direction of the axis O. The second diameter portion 3c is continuous with the rear end of the first diameter portion 3b and extends in the direction of the axis O. The second diameter portion 3c has a smaller diameter than the first diameter portion 3b. Thereby, the step part 3d is formed between the 1st diameter part 3b and the 2nd diameter part 3c.

  The drive shaft 3 is rotatably inserted into the housing 1 while the first diameter portion 3b is supported by the first shaft hole 173 and the third shaft hole 240. Thereby, the first diameter portion 3 b is rotatable in the swash plate chamber 31. Further, the second diameter portion 3 c is located in the second shaft hole 23 and is rotatable in the second shaft hole 23. More specifically, in the present embodiment, the drive shaft 3 rotates in the R1 direction shown in FIGS. As shown in FIGS. 1 and 2, the drive shaft 3 is inserted into the shaft seal device 25 in the first boss portion 171. Thereby, the shaft seal device 25 seals between the inside of the housing 1 and the outside of the housing 1.

  As shown in FIGS. 3 and 4, the rear end of the second diameter portion 3 c protrudes from the second shaft hole 23 and extends into the suction chamber 27. Further, a regulating member 33 is press-fitted on the rear side of the second diameter portion 3c. As a result, the regulating member 33 can rotate together with the drive shaft 3 in the second shaft hole 23. The restricting member 33 includes a flange portion 33a and a cylindrical portion 33b. The flange portion 33 a is formed in a disk shape having a larger diameter than the second diameter portion 3 c and a smaller diameter than the second shaft hole 23. The cylindrical portion 33b is formed in a cylindrical shape having a larger diameter than the second diameter portion 3c and a smaller diameter than the flange portion 33a. The cylindrical portion 33b is integrated with the flange portion 33a, and extends forward in the direction of the axis O from the flange portion 33a.

  As shown in FIGS. 1 and 2, the fixed swash plate 5 is press-fitted into the first diameter portion 3 b of the drive shaft 3 and is disposed in the swash plate chamber 31. As a result, the fixed swash plate 5 can be rotated together with the drive shaft 3 in the swash plate chamber 31 by the rotation of the drive shaft 3. Here, the fixed swash plate 5 has a constant inclination angle with respect to a plane perpendicular to the drive shaft 3. In the swash plate chamber 31, a thrust bearing 35 is provided between the second boss portion 172 and the fixed swash plate 5.

  Each piston 7 is accommodated in each cylinder bore 21a-21f. As shown in FIGS. 5 to 7, compression chambers 45 a to 45 f are formed in the cylinder bores 21 a to 21 f by the pistons 7 and the valve forming plate 9, respectively. 5 to 7, the illustration of each piston 7 is omitted for ease of explanation. The same applies to FIG. 9 described later.

  As shown in FIGS. 1 and 2, each piston 7 is formed with an engaging portion 7a. In each engagement portion 7a, hemispherical shoes 8a and 8b are provided. The pistons 7 are connected to the fixed swash plate 5 by these shoes 8a and 8b. Thereby, the shoes 8 a and 8 b function as a conversion mechanism that converts the rotation of the fixed swash plate 5 into the reciprocating motion of each piston 7. Therefore, each piston 7 can reciprocate between the top dead center of the piston 7 and the bottom dead center of the piston 7 in the cylinder bores 21a to 21f. Hereinafter, the top dead center and the bottom dead center of each piston 7 will be referred to as the top dead center and the bottom dead center, respectively.

  As shown in FIGS. 3 and 4, the rotating body 11 is disposed in the second shaft hole 23. The rotating body 11 is formed in a substantially cylindrical shape having an outer peripheral surface 11a and an inner peripheral surface 11b. The rotating body 11 is formed to have substantially the same diameter as the second shaft hole 23, and the second diameter portion 3c of the drive shaft 3 can be inserted into the inner peripheral surface 11b. Further, by arranging the rotating body 11 in the second shaft hole 23, a control pressure chamber 37 is formed between the support wall 24 and the rotating body 11 in the second shaft hole 23.

  The rotating body 11 is spline-coupled to the outer peripheral surface 30 of the second diameter portion 3c on the inner peripheral surface 11b. Thereby, the rotating body 11 is attached to the drive shaft 3 and can rotate integrally with the drive shaft 3 in the second shaft hole 23. The rotating body 11 moves in the direction of the axis O in the second shaft hole 23 with respect to the drive shaft 3, that is, in the front-rear direction in the second shaft hole 23, due to the differential pressure between the suction pressure and the control pressure. It is possible. The suction pressure and the control pressure will be described later.

  As shown in FIG. 4, the rotating body 11 contacts the cylinder portion 33 b of the regulating member 33 by moving most backward in the direction of the axis O in the second shaft hole 23. Thereby, the restricting member 33 restricts the amount of movement of the rotating body 11 to the rear. On the other hand, as shown in FIG. 3, the rotating body 11 contacts the step portion 3 d of the drive shaft 3 by moving forward in the second shaft hole 23 in the direction of the axis O. Thereby, the step part 3d regulates the amount of forward movement of the rotating body 11.

  A coil spring 39 is provided between the rotating body 11 and the flange portion 33 a of the regulating member 33. The coil spring 39 urges the rotating body 11 toward the front of the second shaft hole 23.

  A second communication passage 41 and a biasing chamber 43 are recessed in the outer peripheral surface 11 a of the rotating body 11. The second communication passage 41 and the urging chamber 43 are separated from each other on the outer peripheral surface 11a. As a result, the second communication passage 41 and the biasing chamber 43 are not in communication.

  As shown in FIG.1 and FIG.2, the 2nd communicating path 41 is gradually formed large in the circumferential direction of the outer peripheral surface 11a as it goes to a rear end from a front end. In other words, the first portion 411 formed small in the circumferential direction of the outer peripheral surface 11a is located on the front end side of the second communication path 41, and the second portion 412 formed large in the circumferential direction of the outer peripheral surface 11a is the second. It is located on the rear end side of the communication path 41. In addition, the shape of the 2nd communicating path 41 can be designed suitably. 3-7, the shape of the 2nd communicating path 41 is simplified and shown in order to make description easy. The same applies to FIGS. 8 and 9 described later. Further, in FIG. 1 and FIG. 2, for the sake of explanation, the rotating body 11 is illustrated in a state of being shifted around the axis O from the position shown in FIGS. 3 to 9.

  As shown in FIGS. 5 and 6, in this compressor, the drive shaft 3 rotates in the R1 direction, and the rotating body 11 rotates in the R1 direction within the second shaft hole 23, whereby the second communication path 41 is The first communication passages 22a to 22f communicate intermittently. The second communication passage 41 has a communication angle around the axis O communicating with each of the first communication passages 22a to 22f per one rotation of the drive shaft 3, depending on the position of the rotating body 11 in the second shaft hole 23. Change. Hereinafter, the communication angle around the axis O where the first communication passages 22a to 22f and the second communication passage 41 communicate with each other per rotation of the drive shaft 3 is simply referred to as a communication angle.

  As shown in FIGS. 3 and 4, the urging chamber 43 is disposed on the outer peripheral surface 11 a on the front side in the axis O direction with respect to the second communication path 41. Thereby, even if the rotary body 11 moves to the axial center O direction within the 2nd shaft hole 23, the urging | biasing chamber 43 does not communicate with each 1st communicating path 22a-22f. The rotating body 11 has a communication groove 43 a that communicates with the urging chamber 43 and opens on the front surface of the rotating body 11. The urging chamber 43 communicates with the control pressure chamber 37 through the communication groove 43a. Here, as shown in FIG. 3, the communication groove 43a is not blocked by the step portion 3d even when the rotary body 11 abuts on the step portion 3d, as shown in FIG. Open to position. For this reason, the urging chamber 43 can always communicate with the control pressure chamber 37 through the communication groove 43 a regardless of the position of the rotating body 11 in the second shaft hole 23.

  As shown in FIG. 7, the urging chamber 43 is formed in the circumferential direction of the outer peripheral surface 11a, and has a substantially fan shape. On the outer peripheral surface 11a, the urging chamber 43 is connected to the first communication passages 22a to 22f communicating with the compression chambers 45a to 45f during the compression stroke or the discharge stroke among the first communication passages 22a to 22f. It is arranged at a position on the opposite side across the axis O. In addition, if it exists in the position which is on the other side on both sides of the axial center O with respect to each 1st communicating path 22a-22f connected to each compression chamber 45a-45f in a compression stroke or a discharge stroke, The shape can be designed as appropriate.

  As shown in FIGS. 3 and 4, the control valve 13 is provided in the rear housing 19. The rear housing 19 is formed with a detection passage 13a and a first air supply passage 13b. Further, a second air supply passage 13 c is formed across the rear housing 19 and the cylinder block 21. The detection passage 13 a is connected to the suction chamber 27 and the control valve 13. The first air supply passage 13 b is connected to the discharge chamber 29 and the control valve 13. The second air supply passage 13 c is connected to the control pressure chamber 37 and the control valve 13. A part of the refrigerant gas in the discharge chamber 29 is introduced into the control pressure chamber 37 through the first and second supply passages 13 b and 13 c and the control valve 13. Further, the control pressure chamber 37 is connected to the suction chamber 27 by a bleed passage (not shown). As a result, the refrigerant gas in the control pressure chamber 37 is led to the suction chamber 27 through the extraction passage. The control valve 13 adjusts the valve opening degree by sensing the suction pressure that is the pressure of the refrigerant gas in the suction chamber 27 through the detection passage 13a. Thus, the control valve 13 adjusts the flow rate of the refrigerant gas introduced from the discharge chamber 29 to the control pressure chamber 37 via the first and second air supply passages 13b and 13c. Specifically, the control valve 13 increases the flow rate of the refrigerant gas introduced from the discharge chamber 29 to the control pressure chamber 37 via the first and second air supply passages 13b and 13c by increasing the valve opening. . On the other hand, the control valve 13 reduces the flow rate of the refrigerant gas introduced from the discharge chamber 29 into the control pressure chamber 37 through the first and second air supply passages 13b and 13c by reducing the valve opening. Thus, the control valve 13 controls the flow rate of the refrigerant gas introduced from the discharge chamber 29 into the control pressure chamber 37 with respect to the flow rate of the refrigerant gas led out from the control pressure chamber 37 to the suction chamber 27. A control pressure that is the pressure of the refrigerant gas in the pressure chamber 37 is controlled. Note that the control pressure chamber 37 may be connected to the swash plate chamber 31 by an extraction passage.

  The suction mechanism 15 includes a second shaft hole 23, first communication paths 22 a to 22 f, and a second communication path 41. The suction mechanism 15 sucks the refrigerant gas in the suction chamber 27 into the compression chambers 45a to 45f. That is, the refrigerant gas in the suction chamber 27 flows through the second shaft hole 23 and reaches the second communication path 41. Accordingly, the suction mechanism 15 sucks the refrigerant gas into the compression chambers 45a to 45f through the first communication passages 22a to 22f and the second communication passage 41.

  In the compressor configured as described above, the fixed swash plate 5 rotates in the swash plate chamber 31 as the drive shaft 3 rotates. As a result, each piston 7 reciprocates between the top dead center and the bottom dead center in the cylinder bores 21a to 21f, so that in each compression chamber 45a to 45f, a suction stroke for sucking refrigerant gas from the suction chamber 27. Then, the compression stroke for compressing the sucked refrigerant gas and the discharge stroke for discharging the compressed refrigerant gas are repeated. In the discharge stroke, the refrigerant gas is discharged into the discharge chamber 29 by the valve forming plate 9. Thereafter, the refrigerant gas in the discharge chamber 29 is discharged to the condenser through the discharge port 29a.

  Here, in this compressor, when the drive shaft 3 is at the rotation angle shown in FIGS. 5 to 7, the cylinder bore 21a, that is, the compression chamber 45a, is the initial stage in which the piston 7 moves from the top dead center toward the bottom dead center. It becomes a stage. The compression chamber 45b is an intermediate stage in which the piston 7 moves from the top dead center toward the bottom dead center, and the compression chamber 45c is a late stage in which the piston 7 moves from the top dead center to the bottom dead center. .

  On the other hand, the compression chamber 45d is an initial stage in which the piston 7 moves from the bottom dead center toward the top dead center. The compression chamber 45e is an intermediate stage in which the piston 7 moves from the bottom dead center to the top dead center, and the compression chamber 45f is a late stage in which the piston 7 moves from the bottom dead center to the top dead center. . Thus, when the piston 7 moves from the bottom dead center toward the top dead center, the compression stroke and the discharge stroke are performed in the compression chambers 45a to 45f. That is, when the drive shaft 3 is at the rotation angle shown in FIG. 6, the compression chamber 45d is in a state immediately after the start of the compression stroke, and the compression chamber 45e is in a state in which the compression stroke is advanced by a certain amount from the compression chamber 45d. . The compression chamber 45f is in a state in which the compression stroke is most advanced, and the discharge stroke is performed when the drive shaft 3 further rotates in the R1 direction.

  In the compressor, the rotary body 11 is moved in the direction of the axis O in the second shaft hole 23 during the suction stroke and the like, so that each compression chamber 45a per rotation of the drive shaft 3 is performed. The flow rate of the refrigerant gas discharged to the discharge chamber 29 from ~ 45f can be changed.

  Specifically, when the flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 is decreased, the control valve 13 reduces the valve opening so that the discharge pressure from the discharge chamber 29 to the control pressure chamber. The flow rate of the refrigerant gas introduced into 37 is decreased. Thus, the control valve 13 decreases the control pressure in the control pressure chamber 37. Thereby, the variable differential pressure, which is the differential pressure between the control pressure and the suction pressure, is reduced.

  For this reason, the rotating body 11 starts to move forward in the direction of the axis O in the second shaft hole 23 from the state shown in FIG. 4 by the biasing force of the coil spring 39. As a result, the second communication path 41 moves forward relative to the first communication paths 22a to 22f. Thereby, the 2nd communication path 41 will be in the state connected with each 1st communication path 22a-22f in the part formed largely in the circumferential direction of the outer peripheral surface 11a. For this reason, in this compressor, the communication angle gradually increases.

  Then, as the variable differential pressure is minimized, as shown in FIG. 3, the rotating body 11 is moved forward most in the second shaft hole 23 and comes into contact with the step portion 3 d. Thereby, in the 2nd communication path 41, it will be in the state connected to each 1st communication path 22a-22f in the 2nd site | part 412, and a communication angle will become the maximum.

  As described above, when the communication angle is maximized, the rotating body 11 rotates around the axis O as shown in FIG. 5, whereby the second communication path 41 passes through the first communication path 22 a and the piston 7. Not only communicates with the compression chamber 45a in the initial stage of moving from the top dead center toward the bottom dead center, but also communicates with the compression chambers 45b-45e through the first communication passages 22b-22e. That is, only the first communication path 22f communicating with the compression chamber 45f in the later stage in which the piston 7 moves from the bottom dead center toward the top dead center is not in communication with the second communication path 41. For this reason, when the drive shaft 3 is at the rotation angle shown in FIG. 5, only the compression chamber 45f is in the compression stroke.

  That is, when the communication angle is the maximum, the compression chambers 45a to 45f are arranged not only during the entire period in which each piston 7 moves from the top dead center toward the bottom dead center, but also from the bottom dead center. The second communication passage 41 is communicated until the middle stage of moving toward the top dead center. Therefore, a part of the refrigerant gas sucked into the compression chambers 45a to 45f while the piston 7 moves from the top dead center toward the bottom dead center moves from the bottom dead center to the top dead center. In the initial stage and the middle stage of moving, the first communication passages 22a to 22f and the second communication passage 41 are discharged to the upstream side of the compression chambers 45a to 45f, that is, outside the compression chambers 45a to 45f. The For this reason, the refrigerant gas compressed when each compression chamber 45a-45f becomes a compression stroke becomes the least. Thus, in this compressor, the flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 is minimized in the discharge stroke.

  On the other hand, when the flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 is increased, the control valve 13 introduces the control pressure chamber 37 from the discharge chamber 29 by increasing the valve opening degree. Increase the flow rate of the refrigerant gas. Thus, the control valve 13 increases the control pressure in the control pressure chamber 37. This increases the variable differential pressure.

  For this reason, against the biasing force of the coil spring 39, the rotating body 11 begins to move backward in the direction of the axis O in the second shaft hole 23 from the state shown in FIG. As a result, the second communication path 41 moves rearward relative to the first communication paths 22a to 22f. Thereby, in the 2nd communicating path 41, in the part formed small in the circumferential direction of the outer peripheral surface 11a, it will be in the state connected with each 1st communicating path 22a-22f. For this reason, the communication angle gradually decreases.

  Then, as the variable differential pressure becomes maximum, as shown in FIG. 4, the rotating body 11 is moved most rearward in the second shaft hole 23 and comes into contact with the cylindrical portion 33 b. Thereby, in the 2nd communication path 41, it will be in the state connected to each 1st communication path 22a-22f in the 1st site | part 411, and a communication angle becomes the minimum.

  As described above, when the communication angle is minimized, as shown in FIG. 6, the rotating body 11 rotates, so that the second communication passage 41 causes the piston 7 to be top dead through the first communication passages 22 a to 22 c. It communicates only with the compression chambers 45a to 45c moving from the point toward the bottom dead center. The first communication passages 22d to 22f communicating with the compression chambers 45d to 45f in which the piston 7 moves from the bottom dead center toward the top dead center are not in communication with the second communication passage 41. For this reason, when the drive shaft 3 is at the rotation angle shown in FIG. 6, the compression chambers 45d to 45f are in the compression stroke.

  That is, when the communication angle is the minimum, the compression chambers 45a to 45f communicate with the second communication path 41 only while the piston 7 moves from the top dead center toward the bottom dead center. For this reason, the refrigerant gas sucked into the compression chambers 45a to 45f is not discharged outside the compression chambers 45a to 45f, and is compressed when the compression chambers 45a to 45f enter the compression stroke. It will be. Thus, in this compressor, the flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 is maximized in the discharge stroke.

  Here, in this compressor, a compressive load can act on the rotating body 11 through the first communication passages 22a to 22f communicating with the compression chambers 45a to 45f during the compression stroke and the discharge stroke. In this regard, in this compressor, the rotator 11 is directed toward the first communication passages 22a to 22f that the urging pressure in the urging chamber 43 communicates with the compression chambers 45a to 45f during the compression stroke or the discharge stroke. Energize.

  Specifically, since the urging chamber 43 communicates with the control pressure chamber 37 through the communication groove 43a, the refrigerant gas in the control pressure chamber 37 flows into the urging chamber 43 through the communication passage 43a. Thereby, in the energizing chamber 43, the refrigerant gas acts so as to press the rotating body 11. As a result, the refrigerant gas in the urging chamber 43 is communicated with each of the compression chambers 45a to 45f during the compression stroke or the discharge stroke from the opposite side across the axis O as the urging pressure. The rotating body 11 is urged toward 22a to 22f. That is, in the state shown in FIGS. 4 and 7, as shown by the white arrow, the urging pressure urges the rotating body 11 toward the first communication paths 22 d to 22 f from the opposite side across the axis O. .

  As described above, when the drive shaft 3 is at the rotation angle shown in FIGS. 5 to 7, the compression chamber 45 f is in the state where the compression stroke is most advanced, and the discharge stroke is not yet performed. However, when the drive shaft 3 further rotates in the R1 direction from the rotation angle shown in FIGS. 5 to 7 and the compression chamber 45f is in the discharge stroke, the rotating body 11 also rotates in the R1 direction together with the drive shaft 3. . For this reason, the urging chamber 43 is located on the opposite side of the axis O with respect to the first communication passage 22f communicating with the compression chamber 45f during the discharge stroke. As a result, the urging pressure urges the rotating body 11 toward the first communication paths 22d to 22f from the opposite side across the axis O even when the compression chamber 45f is in the discharge stroke.

  Thereby, the urging pressure acts on the rotating body 11 so as to press the rotating body 11 against the inner peripheral surface of the second shaft hole 23 against a compressive load. For this reason, in this compressor, even if a compressive load is applied to the rotating body 11, the gaps between the first communication paths 22 a to 22 f and the rotating body 11 are unlikely to increase. For this reason, in this compressor, it is possible to make it difficult for the refrigerant gas compressed in the compression chambers 45 a to 45 f to leak from the gaps between the first communication passages 22 a to 22 f and the rotating body 11. Here, the compressive load acting on the rotating body 11 increases as the flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 increases. In this regard, as described above, in this compressor, the flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 increases as the control pressure increases. Here, the urging chamber 43 communicates with the control pressure chamber 37, and the urging pressure and the control pressure become substantially the same pressure, so that the urging pressure increases as the control pressure increases. That is, when the flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 is maximum, the urging pressure becomes maximum. For this reason, in this compressor, it can prevent suitably that the clearance gap between each 1st communicating path 22a-22f and the rotary body 11 becomes large at the time of the high flow volume from which a compressive load becomes large, and each 1st communicating path 22a. It is possible to make it difficult for the refrigerant gas to leak from the gap between ˜22f and the rotating body 11.

  On the other hand, when the flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 is small, the control pressure is small, so the urging pressure is also small. For this reason, it is difficult for the biasing pressure to prevent the forward movement of the rotating body 11. That is, in this compressor, as the flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 decreases, the compression load acting on the rotating body 11 decreases, so the urging chamber 43 is the rotating body. It is not necessary to bias 11 with a large biasing pressure. Thus, the biasing pressure is difficult to prevent the forward movement of the rotating body 11 when the compression load is low and the flow rate is low. For this reason, in this compressor, the rotating body 11 easily moves in the direction of the axis O in the second shaft hole 23 at a low flow rate.

  Therefore, the compressor according to the first embodiment can improve the volume efficiency and can realize high controllability at a low flow rate.

  In this compressor, the urging chamber 43 can be easily provided in the rotating body 11 by providing the urging chamber 43 in the outer peripheral surface 11 a of the rotating body 11. The urging pressure of the urging chamber 43 suitably urges the rotating body 11 toward the first communication passages 22a to 22f communicating with the compression chambers 45a to 45f during the compression stroke or the discharge stroke. It is possible.

  Further, in this compressor, inlet side control is performed in which the control valve 13 changes the flow rate of the refrigerant gas introduced from the discharge chamber 29 to the control pressure chamber 37 through the first and second air supply passages 13b and 13c. For this reason, the control pressure chamber 37 can be quickly increased in pressure, and the flow rate of the refrigerant gas discharged from each compression chamber 45 to the discharge chamber 29 can be increased rapidly.

(Example 2)
As shown in FIG. 8, in the compressor according to the second embodiment, the urging chamber 44 is recessed in the outer peripheral surface 30 of the second diameter portion 3c. The urging chamber 44 is always rotated on the outer peripheral surface 30 at a position where the rotating body 11 is not exposed in the second shaft hole 23 even when the rotator 11 moves most backward in the second shaft hole 23, that is, on the outer peripheral surface 30. It is disposed at a location facing the inner peripheral surface 11 b of the body 11. In addition, a communication groove 44 a that communicates with the urging chamber 44 and extends to the stepped portion 3 d is formed on the outer peripheral surface 30. The urging chamber 44 communicates with the control pressure chamber 37 through the communication groove 44a. Thereby, like the urging chamber 43 in the compressor of the first embodiment, the urging pressure in the urging chamber 44 is substantially the same as the control pressure. Here, since the communication groove 44a extends to the step portion 3d, the urging chamber 44 is a case where the rotating body 11 moves most forward in the second shaft hole 23 and is in contact with the step portion 3d. Even if it exists, it can communicate with the control pressure chamber 37. That is, even in this compressor, the urging chamber 44 can always communicate with the control pressure chamber 37 through the communication groove 44 a regardless of the position of the rotating body 11 in the second shaft hole 23.

  As shown in FIG. 9, the urging chamber 44 is formed in the circumferential direction of the outer peripheral surface 30 and has a substantially fan shape. The urging chamber 44 is connected to the first communication passages 22a to 22f communicating with the compression chambers 45a to 45f during the compression stroke or the discharge stroke among the first communication passages 22a to 22f on the outer peripheral surface 30. They are arranged on the same side. That is, the urging chamber 44 faces the first communication passages 22a to 22f communicating with the compression chambers 45a to 45f during the compression stroke or the discharge stroke, with the rotating body 11 interposed therebetween. The shape of the urging chamber 44 can be appropriately designed as long as the first communication passages 22a to 22f communicating with the compression chambers 45a to 45f during the compression stroke or the discharge stroke are located on the same side. is there. Other configurations of the compressor are the same as those of the compressor according to the first embodiment, and the same components are denoted by the same reference numerals and detailed description thereof is omitted.

  In this compressor, the urging pressure in the urging chamber 44 urges the rotating body 11 toward the first communication passages 22a to 22f communicating with the compression chambers 45a to 45f during the compression stroke or the discharge stroke. To do. That is, in the state shown in FIG. 9, as shown by the white arrows, the urging pressure is applied from the side facing the first communication passages 22d to 22f toward the first communication passages 22d to 22f. To force. Thus, even in this compressor, the urging pressure acts on the rotating body 11 so as to press the rotating body 11 against the inner peripheral surface of the second shaft hole 23 against the compressive load. Thus, even in this compressor, the refrigerant gas hardly leaks from the gaps between the first communication passages 22a to 22f and the rotating body 11. Other functions of this compressor are the same as those of the compressor of the first embodiment.

  In this compressor, the urging chamber 44 can be easily provided on the drive shaft 3 by recessing the urging chamber 44 in the outer peripheral surface 30 of the second diameter portion 3c. The urging pressure of the urging chamber 44 preferably urges the rotating body 11 toward the first communication passages 22a to 22f communicating with the compression chambers 45a to 45f during the compression stroke or the discharge stroke. It is possible.

  In the above, the present invention has been described with reference to the first and second embodiments. However, the present invention is not limited to the first and second embodiments, and can be appropriately modified and applied without departing from the spirit of the present invention. Needless to say.

  For example, you may comprise the compressor of Example 1, 2 as a double-headed piston type compressor.

  Further, by combining the compressor of the first embodiment and the compressor of the second embodiment, the rotating body 11 is being compressed during the compression stroke by the urging pressure of the urging chamber 43 and the urging pressure of the urging chamber 44. It is good also as a structure urged | biased toward each 1st communicating path 22a-22f side connected with each compression chamber 45a-45f in a discharge stroke.

  Further, in the compressors according to the first and second embodiments, the rotating body 11 moves forward in the direction of the axis O in the second shaft hole 23, so that the compression chambers 45 a to 45 f per rotation of the drive shaft 3. The flow rate of the refrigerant gas discharged into the discharge chamber 29 may be increased.

  Further, in the compressors of the first and second embodiments, the flow angle of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 per one rotation of the drive shaft 3 is increased by increasing the communication angle. By reducing the communication angle, the flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 per rotation of the drive shaft 3 may be reduced.

  In the compressors of the first and second embodiments, instead of the shoes 8a and 8b, a swing plate is supported on the rear surface side of the fixed swash plate 5 via a thrust bearing, and the swing plate and each piston 7 are supported. A wobble type conversion mechanism that connects the two by a connecting rod may be adopted.

  In the compressors of the first and second embodiments, the control pressure chamber 37 is formed in the second shaft hole 23. However, the present invention is not limited to this, and the control pressure chamber 37 may be formed in the rear housing 19 or the rear housing. The control pressure chamber 37 may be formed in both the cylinder block 21 and the cylinder block 21.

  Furthermore, in the compressors of the first and second embodiments, the swash plate chamber 31 may also serve as the suction chamber 27.

  In the compressors of the first and second embodiments, the communication angle varies depending on the position of the rotating body 11 in the second shaft hole 23, that is, the position of the rotating body 11 in the axis O direction. The flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 is changed. However, the present invention is not limited to this, and the communication areas of the first communication passages 22a to 22f and the second communication passage 41 change according to the position of the rotating body 11 in the direction of the axis O, thereby causing the compression chambers 45a to 45f to change. The flow rate of the refrigerant gas discharged from the discharge chamber 29 to the discharge chamber 29 may be changed.

  Furthermore, in the compressors of the first and second embodiments, external control for controlling the control pressure by switching the current to the control valve 13 from the outside may be performed, and the control is performed without depending on the current from the outside. You may perform internal control which controls a pressure. Here, when external control is performed and the control valve 13 is configured to reduce the valve opening by turning off the current to the control valve 13, the valve opening is reduced when the compressor is stopped. And the control pressure in the control pressure chamber 37 can be lowered. For this reason, since the compressor can be started in a state where the flow rate of the refrigerant gas discharged from each compression chamber 45 to the discharge chamber 29 is minimized, the start shock can be reduced.

  Further, in the compressors of the first and second embodiments, the discharge side control in which the flow rate of the refrigerant gas led out from the control pressure chamber 37 to the suction chamber 27 or the swash plate chamber 31 through the extraction passage is changed by the control valve 13 may be performed. . In this case, since the amount of the refrigerant gas in the discharge chamber 29 used for changing the flow rate of the refrigerant gas discharged from the compression chambers 45a to 45f to the discharge chamber 29 can be reduced, the efficiency of the compressor is increased. Can do. Further, in this case, if the valve opening is increased by turning off the current to the control valve 13, the valve opening increases when the compressor is stopped, and the control pressure in the control pressure chamber 37 is reduced. Can be lowered. For this reason, since the compressor can be started in a state where the flow rate of the refrigerant gas discharged from each compression chamber 45 to the discharge chamber 29 is minimized, the start shock can be reduced.

  The present invention can be used for a vehicle air conditioner or the like.

DESCRIPTION OF SYMBOLS 1 ... Housing 3 ... Drive shaft 5 ... Fixed swash plate 7 ... Piston 9 ... Valve formation plate (discharge valve)
DESCRIPTION OF SYMBOLS 11 ... Rotating body 13 ... Control valve 21a-21f ... Cylinder bore 22a-22f ... 1st communicating path 23 ... 2nd shaft hole (shaft hole)
DESCRIPTION OF SYMBOLS 29 ... Discharge chamber 31 ... Swash plate chamber 37 ... Control pressure chamber 41 ... 2nd communicating path 43, 44 ... Energizing chamber 45a-45f ... Compression chamber 173 ... 1st shaft hole (shaft hole)
240 ... third shaft hole (shaft hole)
O ... axis

Claims (3)

A housing having a cylinder block in which a plurality of cylinder bores are formed, 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 is rotatable 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 the cylinder bore and is connected to the fixed swash plate;
A discharge valve for discharging the refrigerant in the compression chamber to the discharge chamber;
A rotating body provided on the drive shaft, rotating integrally with the drive shaft, and movable relative to the drive shaft in the axial direction of the drive shaft based on a control pressure;
The control pressure and a control valve for controlling,
The cylinder block is formed with a first communication path communicating with the cylinder bore,
The rotating body is formed with a second communication path that intermittently communicates with the first communication path 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 rotating body in the axial direction;
The rotating body moves in the axial direction so that the flow rate of the refrigerant discharged from the compression chamber to the discharge chamber increases as the control pressure increases,
At least one of the drive shaft and the rotating body communicates with the control pressure chamber, and the first communication communicates the rotating body with the compression chamber during a compression stroke or a discharge stroke by an internal biasing pressure. A piston-type compressor, wherein a biasing chamber that biases toward the passage side is formed.   The urging chamber is recessed on the outer peripheral surface of the rotating body, and is located on the opposite side of the first communication path communicating with the compression chamber during a compression stroke or a discharge stroke with the shaft center therebetween. The piston type compressor according to claim 1.   2. The urging chamber is recessed on an outer peripheral surface of the drive shaft, and is located on the same side with respect to the first communication passage communicating with the compression chamber during a compression stroke or a discharge stroke. Piston type compressor.

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