KR100896267B1 - Refrigerant suction structure in fixed displacement type piston compressor - Google Patents

Abstract

(Problem) The effect of reducing the starting shock of a fixed displacement piston compressor using a rotary valve is increased.

(Solution means) The first rotary valve 35 and the second rotary valve 36 are formed in the rotary shaft 21 corresponding to the cylinder blocks 11 and 12. The valve body 42 is fitted in the cylinder 411 so as to partition the first pressure chamber 412. A first bellows 51 and a second bellows 52 are connected to the partition wall plate 48 that divides the first pressure chamber 412 and the second pressure chamber 491. The 1st bellows 51 is accommodated in the 1st pressure chamber 412 in the state connected to the valve body 42, and the 2nd bellows 52 is accommodated in the 2nd pressure chamber 491. As shown in FIG. The throttle passage 53 formed in the partition wall plate 48 communicates with the first volume variable chamber 511 in the first bellows 51 and the second volume variable chamber 521 in the second bellows 52. .

Cylinder block, rear housing, discharge chamber, valve body, double head piston

Description

REFRIGERANT SUCTION STRUCTURE IN FIXED DISPLACEMENT TYPE PISTON COMPRESSOR}

SUMMARY OF THE INVENTION The present invention includes a rotary valve having an introduction passage for introducing refrigerant from a suction pressure region into a compression chamber defined by a piston in a cylinder bore, whereby the rotary valve rotates integrally with a rotating shaft. A refrigerant suction structure in a type piston compressor.

Piston type compressors using rotary valves (see, for example, Patent Documents 2 and 5) are compared to piston type compressors using reed valve type suction valves (see Patent Documents 1 and 4, for example) into the cylinder bore. Suction resistance at the time of inhaling suction gas is small, and energy efficiency is excellent.

As described in paragraph [0006] of Patent Document 2, when the compressor starts up, the torque increases rapidly with the compression of the gas, which is applied to the vehicle engine (internal combustion engine) as a load. Therefore, the driving speed of the vehicle decreases for a moment and a start shock occurs that the occupant of the vehicle feels shock.

In the piston compressor disclosed in Patent Literature 2, a rotary valve which is integrally rotated with the rotary shaft is formed to be movable in the axial direction of the rotary shaft, and the rotary valve is in the axial direction of the rotary shaft in accordance with the pressure supplied to the control pressure chamber. It is possible to change the position in the. In addition, a bypass groove is formed in the rotary valve in which almost all cylinder bores can communicate with the suction port formed with respect to the center of the cylinder block. The rotary valve is disposed at the position in the axial direction of the rotary shaft so that the bypass groove is at a position in which almost all cylinder bores can communicate with the suction port at the time of stopping the operation and at the time of starting. Therefore, even when the piston compresses the gas in the cylinder bore at the start, the gas in the cylinder bore returns to the inlet via the bypass groove, so that no starting shock occurs.

The clearance in the main surface of a rotary valve should be made as small as possible so that gas may not leak along this main surface and a rotary valve may rotate. However, in the configuration in which the rotary valve is movable in the axial direction of the rotary shaft, a clearance for allowing the rotary valve to be movable in the axial direction of the rotary shaft is required, but management of such clearance is very difficult.

In the compressor disclosed in Patent Document 3, a starting load reduction device is formed in the middle of a suction passage leading to the suction chamber. The starting load reduction device includes a spool valve constituting an oil damper, and a gap is formed between the damper portion of the spool valve and the housing. When the spool valve moves in the direction of opening the suction passage, the oil in the damper chamber escapes into the intermediate chamber a small amount from the gap. Therefore, the moving speed of the spool valve becomes slow, and the opening speed of the suction passage becomes slow. As a result, the starting shock is alleviated.

In the piston compressor disclosed in Patent Document 4, there is formed a differential pressure sensing on / off valve that opens and closes by a differential pressure between a discharge pressure and a suction pressure. The differential pressure sensing on / off valve is interposed between the low pressure refrigerant channel for introducing refrigerant from the outside of the compressor and the suction chamber in the compressor, and the differential pressure sensing on / off valve is closed when the compressor is started with the pressure balanced. Inflow of the refrigerant from the outside of the compressor to the suction chamber is stopped. As a result, the starting shock is alleviated.

[Patent Document 1] Japanese Patent Application Laid-Open No. 64-88064

[Patent Document 2] Japanese Patent Application Laid-Open No. 7-119631

[Patent Document 3] Japanese Patent Application Laid-Open No. 7-139474

[Patent Document 4] Japanese Patent Application Laid-Open No. 2000-145629

[Patent Document 5] Japanese Laid-Open Patent Publication No. 2006-83835

However, in the compressor described in Patent Document 3, even when the suction passage is closed by the spool valve, the refrigerant remains in the suction chamber, and the residual refrigerant is sucked into the cylinder bore and compressed. In addition, in the compressor disclosed in Patent Document 4, even when the differential pressure sensing on / off valve is closed, the refrigerant remains in the suction chamber, and the residual refrigerant is sucked into the cylinder bore and compressed. Since the volume of the suction chamber is enlarged to suppress the suction pulsation, the amount of refrigerant sucked into the cylinder bore is large when the differential pressure sensing on / off valve is in a closed state or the suction passage is closed. The effect is not enough.

An object of the present invention is to enhance the effect of mitigating shock.

In the invention of claims 1 to 9, the piston is accommodated in a plurality of cylinder bores arranged around the rotation shaft, the piston is linked to the rotation of the rotation shaft through a cam body integrated with the rotation shaft, A rotary valve having an introduction passage for introducing refrigerant from a suction pressure region into a compression chamber partitioned in the cylinder bore by the piston, the rotary valve integrally rotating with the rotary shaft, A refrigerant suction structure in a fixed displacement piston type compressor connected to an external drive source through a clutch is an object, and the invention of claim 1 is in a state in which the suction pressure region in the compressor and the outlet of the inlet passage are in communication with each other. Switching means capable of switching to a pressure sensor is provided, and the switching means includes a suction pressure in the compressor. A valve body which is switched to a position for communicating with an outlet of the region and the introduction passage and a position for blocking, a return spring for returning the valve body from the communicating position to the blocking position, and a positional displacement of the valve body. And a throttle passage (narrow passage) which communicates the first volume variable chamber and the second volume variable chamber with a first volume variable chamber for changing the volume, a second volume variable chamber for volume change, and the first volume variable chamber. A fluid is put into the chamber and the second volume variable chamber, and when the first volume variable chamber changes in volume, the fluid passes through the throttle passage.

The pressure in the introduction passage downstream of the valve body when the compressor is running (when the rotating shaft is rotating) is lower than the pressure in the introduction passage when the compressor is not being operated. When the operation of the compressor is stopped, the valve body is in a position to shut off, but when the operation of the compressor starts, the pressure in the downstream introduction passage is lower than the valve body, and the valve body moves from a position where the valve body shuts off. do. During this movement, the volume of the first variable volume chamber changes, and the fluid passes through the throttle passage. As the fluid passes through the throttle passage, the volume of the second volumetric chamber also changes. The passage resistance when the fluid passes through the throttle passage slows the volume change of the first volume variable chamber and the second volume variable chamber, and the movement of the valve body is braked. Therefore, when the compressor starts to operate, the starting shock is alleviated. Since the communication between the suction pressure region in the compressor and the outlet of the introduction passage is interrupted, the amount of refrigerant compressed when the switching means is in the interrupted state is small, and the effect of mitigating start shock is high.

When the operation of the compressor is stopped, the valve body returns to the cut position by the spring force of the return spring. The use of a return spring is a simple structure for returning to a position which cuts off a valve body.

As a very suitable example, the first volumetric variable chamber is formed between the partition wall and the first chamber forming member having the first movable portion that is displaced, and the second volume variable chamber is the partition wall and the position. It is formed between the 2nd chamber formation member which has a 2nd movable part displaced, The said throttle passage penetrates the said partition wall, and communicates with the said 1st volume variable chamber and the said 2nd volume variable chamber, The volume of the 1 volume variable chamber changes with the positional displacement of the said 1st movable part, and the volume of the 2nd volume variable chamber changes with the positional displacement of the 2nd movable part.

When the operation of the compressor is started, the pressure in the introduction passage downstream from the valve body is lowered and moves from the position at which the valve body is blocked to communicate with the valve body. In this movement, the first movable portion is displaced so that the volume of the first volume variable chamber changes, and the fluid passes through the throttle passage. As the fluid passes through the throttle passage, the second movable portion is also displaced, and the volume of the second variable volume chamber changes. The passage resistance at this time slows the volume change of the 1st volume variable chamber and the 2nd volume variable chamber, and the movement of a valve body is braked.

As a very suitable example, the first chamber forming member is a first bellows connected to the partition wall, and the second chamber forming member is a second bellows connected to the partition wall.

The bellows is very suitable for avoiding leakage of fluid from inside the first and second volume variable chambers.

As a very suitable example, the valve body is attached to the movable end of the first bellows.

The first bellows expands and contracts in accordance with the positional displacement of the valve body. As the first bellows increases, the volume of the first volumetric variable chamber increases, while the second bellows shrinks to reduce the volume of the second volumetric variable chamber. As the first bellows decreases, the volume of the first volumetric variable chamber decreases and the volume of the second volumetric variable chamber increases.

As a very suitable example, the moving distance of the movable end of the first bellows when the volume change is the same size is larger than the moving distance of the movable end of the second bellows.

Such a configuration is very suitable for cutting the moving distance of the valve body from the position to shut off to the position to communicate with.

In a very suitable example, the fluid is a liquid.

Liquid is very suitable for increasing the passage resistance in the throttle passage and slowing down the moving speed of the valve body.

As a very suitable example, when the switching means is in the blocking state, the valve body is disposed at a position that blocks the inlet of the introduction passage from the suction pressure region in the compressor.

Since the communication between the suction pressure region in the compressor and the inlet of the introduction passage is interrupted, the amount of refrigerant compressed when the switching means is in the interrupted state is small, and the effect of reducing the starting shock is high.

The introduction passage has an inlet at the end face of the rotary valve, an outlet at a main surface of the rotary valve, and the introduction passage has an in-axis passage extending in the direction of the rotation axis of the rotation shaft inside the rotation shaft. The outlet of the introduction passage penetrates through the main surface of the rotation shaft to communicate with the in-axis passage, and the valve body slides in the introduction passage from the inlet of the introduction passage in the direction of the rotation axis. The valve body is inserted into the valve shaft, and the valve body moves in the direction of the rotation axis to be switched to the communicating position and the blocking position, and the blocking position is such that the valve body is separated from the shaft passage. It is a position to block the exit of the introduction passage.

When the valve body is slid and disposed at the blocking position, the outlet of the inlet passage is blocked from the in-axis passage, and the inflow of refrigerant from the in-axis passage to the compression chamber is prevented. The configuration in which the outlet of the introduction passage is blocked from the in-axis passage by the valve body inside the in-axis passage is optimal for reducing the amount of refrigerant compression when the switching means is in a state of blocking.

As a very suitable example, a rear housing is connected to a cylinder block forming the cylinder bore, a suction chamber is formed in the rear housing, and the valve body is formed in the rear housing.

This invention brings the outstanding effect that the effect of a starting shock relief can be heightened.

(The best form to carry out invention)

EMBODIMENT OF THE INVENTION Hereinafter, 1st Embodiment which actualized this invention is described based on FIG.

As shown in FIG. 1, the front housing 13 is connected to one cylinder block 11 of the pair of cylinder blocks 11 and 12 connected, and the rear housing 14 is connected to the other cylinder block 12. As shown in FIG. ) Is connected. The cylinder blocks 11 and 12, the front housing 13, and the rear housing 14 comprise the whole housing of the fixed displacement piston type compressor 10. As shown in FIG. The front housing 13 is formed with a discharge chamber 131 as a discharge pressure region in the compressor, and the rear housing 14 has a discharge chamber 141 as a discharge pressure region in the compressor and a suction chamber 142 as a suction pressure region in the compressor. ) Is formed. The inside of a compressor means the inside of the whole housing | casing of the fixed displacement type piston compressor 10, and the outside of a compressor means the outside of the whole housing of the fixed displacement piston type compressor 10. As shown in FIG.

A valve plate 15, a valve forming plate 16, and a retainer forming plate 17 are interposed between the cylinder block 11 and the front housing 13. The valve plate 18, the valve forming plate 19, and the retainer forming plate 20 are interposed between the cylinder block 12 and the rear housing 14. Discharge ports 151 and 181 are formed in the valve plates 15 and 18, and discharge valves 161 and 191 are formed in the valve formation plates 16 and 19. The discharge valves 161 and 191 open and close the discharge ports 151 and 181. Retainers 171 and 201 are formed in the retainer forming plates 17 and 20. The retainers 171, 201 regulate the opening degree of the discharge valves 161, 191.

The rotary shaft 21 is rotatably supported by the cylinder blocks 11 and 12. Shaft holes 111 and 121 are formed through the cylinder blocks 11 and 12, and the rotating shaft 21 passes through the shaft holes 111 and 121. The outer circumferential surface of the rotating shaft 21 is in contact with the inner circumferential surfaces of the shaft holes 111 and 121, and the rotating shaft 21 is directly supported by the cylinder blocks 11 and 12 through the inner circumferential surfaces of the shaft holes 111 and 121. The outer circumferential surface portion of the rotating shaft 21 in contact with the shaft hole 111 is a seal main surface 211, and the outer circumferential surface portion of the rotating shaft 21 in contact with the shaft hole 121 is a seal main surface 212. .

The swash plate 23 as a cam body is fixed to the rotating shaft 21. The swash plate 23 is housed in the swash plate chamber 24 between the cylinder blocks 11 and 12. A lip seal type shaft seal member 22 is interposed between the front housing 13 and the rotation shaft 21. The shaft seal member 22 prevents gas leakage between the front housing 13 and the rotation shaft 21. The protruding end of the rotating shaft 21 which protrudes from the front housing 13 to the outside is connected to the vehicle engine 26 which is an external drive source via the electromagnetic clutch 25. As shown in FIG. The rotary shaft 21 obtains a rotational driving force from the vehicle engine 26 via the electromagnetic clutch 25.

As shown in Fig. 2 (a), the cylinder block 11 is formed such that a plurality of cylinder bores 27 are arranged around the rotation shaft 21. As shown in FIG. 2 (b), the cylinder block 12 is formed such that a plurality of cylinder bores 28 are arranged around the rotation shaft 21. The double headed piston 29 is accommodated in the cylinder bores 27 and 28, which are paired with the front and rear (front housing 13 side and the rear housing 14 rear).

As shown in FIG. 1, the rotational motion of the swash plate 23 integrally rotating with the rotation shaft 21 is transmitted to the double head piston 29 via the shoe 30, so that the double head piston 29 is a cylinder bore 27,. 28) Reciprocate back and forth inside. The double head piston 29 partitions the compression chambers 271 and 281 into the cylinder bores 27 and 28.

In the rotation shaft 21, an in-axis passage 31 is formed along the rotation axis 210 of the rotation shaft 21. The inlet 311 of the in-axis passage 31 opens in the suction chamber 142 in the rear housing 14 at the end face 213 of the rotating shaft 21 in the cylinder block 12. In the rotating shaft 21 in the shaft hole 111, the outlet 312 of the in-axis passage 31 is formed so that it may open to the seal | sticker main surface 211 of the rotating shaft 21. As shown in FIG. In the rotating shaft 21 in the shaft hole 121, an outlet 313 of the in-axis passage 31 is formed to open to the seal main surface 212 of the rotating shaft 21.

As shown in FIG. 2 (a), the communication path 32 is formed in the cylinder block 11 so as to communicate with the cylinder bore 27 and the shaft hole 111. As shown in Fig. 2 (b), the communication path 33 is formed in the cylinder block 12 so as to communicate with the cylinder bore 28 and the shaft hole 121. As the rotation shaft 21 rotates, the outlets 312 and 313 of the in-axis passage 31 communicate with the communication paths 32 and 33 intermittently.

When the double head piston 29 is in the state of the suction stroke on the cylinder bore 27 side (the stroke in which the double head piston 29 moves from the left side to the right side in FIG. 1), the outlet 312 and the communication path 32 Communicate. When the two-head piston 29 is in the intake stroke state on the cylinder bore 27 side, the refrigerant in the in-axis passage 31 of the rotating shaft 21 passes through the outlet 312 and the communication path 32 to the cylinder bore ( 27 is sucked into the compression chamber 271.

When the double-headed piston 29 is in the discharge stroke state (the double-headed piston 29 moves from the right side to the left side in Fig. 1) on the cylinder bore 27 side, the outlet 312 and the communication path 32 Communication is blocked. When the double head piston 29 is in the discharge stroke state on the cylinder bore 27 side, the refrigerant in the compression chamber 271 pushes the discharge valve 161 out of the discharge port 151 and discharges the discharge chamber 131. do. The refrigerant discharged to the discharge chamber 131 flows out to the external refrigerant circuit 34 through the passage 341.

When the double head piston 29 is in the state of the suction stroke on the cylinder bore 28 side (the stroke in which the double head piston 29 moves from the right side to the left side in Fig. 1), the outlet 313 and the communication path 33 Communicate. When the two-head piston 29 is in the intake stroke state on the cylinder bore 28 side, the refrigerant in the in-axis passage 31 of the rotary shaft 21 passes through the outlet 313 and the communication path 33 to the cylinder bore ( 28 is sucked into the compression chamber 281.

When the double-headed piston 29 is in the discharge stroke state (the stroke in which the double-headed piston 29 moves from the left side to the right side in FIG. 1) on the cylinder bore 28 side, the outlet 313 and the communication path 33 Communication is blocked. When the double head piston 29 is in the discharge stroke state on the cylinder bore 28 side, the refrigerant in the compression chamber 281 pushes the discharge valve 191 from the discharge port 181 and discharges it to the discharge chamber 141. do. The refrigerant discharged into the discharge chamber 141 flows out to the external refrigerant circuit 34 through the passage 342.

On the external refrigerant circuit 34, a heat exchanger 37 for extracting heat from the refrigerant, an expansion valve 38 and a heat exchanger 39 for transferring ambient heat to the refrigerant are interposed. The expansion valve 38 controls the refrigerant flow rate in accordance with the variation of the gas temperature at the outlet side of the heat exchanger 39. The refrigerant flowing out to the external refrigerant circuit 34 is returned to the suction chamber 142.

The part of the seal main surface 211 of the rotating shaft 21 becomes the 1st rotary valve 35 integrally formed in the rotating shaft 21, and the part of the seal main surface 212 of the rotating shaft 21 is connected to the rotating shaft 21. As shown in FIG. It becomes the 2nd rotary valve 36 integrally formed. That is, the rotating shaft 21 is a rotary valve. The rotation axis 210 is a rotation axis of the rotary valve, and the end face 213 (that is, the end face of the rotary valve) of the rotation shaft 21 intersects the rotation axis 210 of the rotary valve. The in-axis passage 31 and the outlets 312 and 313 constitute an introduction passage of the rotary valve, the shaft hole 111 is a valve accommodating chamber for accommodating the first rotary valve 35, and the shaft hole 121 is It is a valve accommodation chamber which accommodates the 2nd rotary valve 36. As shown in FIG.

As shown in FIG. 3 and FIG. 4, the base 40 is integrally formed in the end wall of the rear housing 14 which forms the suction chamber 142, and the cylinder 41 is formed in the inner wall surface of the base 40. As shown in FIG. ) Is integrally formed. The spool-shaped valve body 42 is slidably inserted into the cylinder 411 of the cylinder 41. The valve body 42 includes a disk-shaped piston portion 43 and a cylindrical portion 44, and the cylindrical portion 44 has an introduction port 441 open to the outer circumferential surface of the cylindrical portion 44, and furthermore, a cylindrical portion 44. It is formed so that it may communicate with the cylinder 442 of the part 44. The cylinder 442 is an internal passage of the valve body 42. The piston portion 43 partitions the first pressure chamber 412 into the cylinder 411 of the cylinder 41.

At the end face of the cylinder block 12 on the rear housing 14 side, a cylindrical guide cylinder 45 is integrally formed so as to face the cylinder 41. The cylinder 451 of the guide cylinder 45 communicates with the inlet 311 of the in-axis passage 31 (introduction passage). The tip of the guide cylinder 45 and the tip of the cylinder 41 are separated from each other, and the cylindrical portion 44 of the valve body 42 is slidably fitted to the guide cylinder 45. A circlip 46 is attached to the inner circumferential surface of the guide cylinder 45, and a return spring 47 is interposed between the circlip 46 and the piston 43. The return spring 47 elastically supports the valve body 42 so as to be close to the pedestal 40. As the valve body 42 approaches the pedestal 40, the volume of the first pressure chamber 412 decreases.

In the state shown in FIG. 4, the whole inlet 441 is in the position which exposes in the suction chamber 142, and the in-axis passage 31 of the cylinder 451 of the guide cylinder 45, and the cylindrical part 44 It communicates with the suction chamber 142 via the cylinder 442 and the inlet 441. In the state shown in FIG. 3, the whole inlet 441 is in the position which entered the cylinder 411, and the communication between the axial passage 31 and the suction chamber 142 is interrupted | blocked. 4 shows a state in which the valve body 42 is in a position where the in-cylinder passage 31 and the suction chamber 142 communicate with each other, and FIG. 3 shows that the valve body 42 has an in-axis passage 31 and a suction chamber ( 142 indicates the state in which the position to block.

As shown in FIG. 3 and FIG. 4, the recessed part 401 is formed in the outer wall surface of the base 40, and the partitioned wall board 48 as a partition wall is accommodated in the recessed part 401. As shown in FIG. A bottomed cylindrical cover 49 is joined to and fixed to the outer surface of the pedestal 40 by tightening the screw 50. The lid 49 presses the partition wall plate 48 to the bottom of the recess 401 by tightening the screw 50.

The through hole 55 is formed in the bottom of the recessed portion 401 so as to communicate with the first pressure chamber 412. The first bellows 51 is connected to the inner surface 56 of the partition wall plate 48 opposite to the through hole 55. The first movable end 512 of the first bellows 51 is attached to the piston portion 43 of the valve body 42, so that the first movable end of the valve body 42 and the first bellows 51 ( 512 is movable integrally. The first bellows 51 expands and contracts in the direction of the rotation axis 210 of the rotary shaft 21, and the first bellows 51 is variable in the first volume in the first pressure chamber 412 and in the through hole 55. The chamber 511 is partitioned. The volume of the first variable volume chamber 511 partitioned by the first bellows 51 as the first chamber forming member is the positional displacement of the first movable end 512 as the first movable portion (direction of the rotation axis 210). Positional displacement). That is, the 1st volumetric variable chamber 511 formed between the partition wall board 48 and the 1st movable end 512 is a position displacement of the valve body 42 (position displacement in the direction of the rotation axis 210). To change the volume.

The second bellows 52 is connected to the outer surface 57 of the partition wall plate 48 in the cylinder 491 of the lid 49. The second bellows 52 expands and contracts in the direction of the rotation axis 210 of the rotation shaft 21, and the second bellows 52 partitions the second volume variable chamber 521 in the cylinder 491. The second volume variable chamber 521 is formed between the partition wall plate 48 and the second movable end 522. The volume of the second variable volume chamber 521 partitioned by the second bellows 52 as the second chamber forming member is the positional displacement of the second movable end 522 as the second movable portion (direction of the rotation axis 210). Positional displacement).

When the volume change is the same size, the moving distance of the first movable end 512 of the first bellows 51 is larger than the moving distance of the second movable end 522 of the second bellows 52. That is, when the volume of the bellows 51 and 52 increases or decreases by the same magnitude | size, the moving distance of the 1st movable end 512 is larger than the movement distance of the 2nd movable end 522. As shown in FIG.

In the partition wall plate 48, the throttle passage 53 is formed so as to communicate with the first volume variable chamber 511 and the second volume variable chamber 521. The first volumetric variable chamber 511, the second volumetric variable chamber 521, and the throttle passage 53 are filled with oil (liquid liquid).

The passage 55 communicates with the suction chamber 142 via the groove 561 formed on the inner surface 56 of the partition wall plate 48 and the passage 54 formed in the pedestal 40, and the suction chamber 142. ) Is exerted on the first pressure chamber 412. The pressure in the first pressure chamber 412 is opposed to the pressure in the cylinder 442 through the valve body 42.

The cylinder 491 communicates with the suction chamber 142 through the groove 571 and the passage 54 formed on the outer surface 57 of the partition wall plate 48, so that the pressure of the suction chamber 142 flows into the cylinder ( 491). In the following, the cylinder 491 is described as the second pressure chamber 491.

As shown in FIG. 1, the electromagnetic clutch 25 is subjected to magnetization and demagnetization control of the control computer C. As shown in FIG. The air conditioning apparatus operation switch 58, the room temperature setter 59, and the room temperature detector 60 are signal-connected to the control computer C. As shown in FIG. When the air conditioner operating switch 58 is in the ON state, the control computer C is based on the temperature difference between the target room temperature set by the room temperature setter 59 and the detected room temperature detected by the room temperature detector 60. Thus, the current supply (excitation element) to the electromagnetic clutch 25 is controlled.

When the detected temperature is lower than the target temperature, or when the detected temperature is higher than the target temperature and the temperature difference between the detected temperature and the target temperature is equal to or less than the allowable difference, the control computer C determines the electronic clutch 25. Stop supply of current to At this time, the electromagnetic clutch 25 is cut off, and the rotational driving force of the vehicle engine 26 is not transmitted to the rotational shaft 21. When the detection temperature is higher than the target temperature and the temperature difference between the detection temperature and the target temperature exceeds the allowable difference, the control computer C supplies a current to the electromagnetic clutch 25. At this time, the electromagnetic clutch 25 is in a connected state, and the rotation driving force of the vehicle engine 26 is transmitted to the rotation shaft 21.

The fixed displacement piston type compressor 10 is said to be in an operation stop state (state in which the electromagnetic clutch 25 is blocked). In this state, the pressure in a compressor is balanced, and the valve body 42 is in the position to cut off by the spring force of the return spring 47 shown in FIG. When the operation of the fixed displacement piston type compressor 10 is started, the refrigerant in the shaft passage 31 and the refrigerant in the cylinders 451 and 442 are compressed chamber 271 (see FIG. 1) and the compression chamber. Since suction is performed at 281, the pressure in the in-axis passage 31 and in the cylinders 451 and 442 is lowered by this suction action. That is, the pressure in the axial passage 31 and the cylinders 451 and 442 is lower than the pressure in the suction chamber 142. The pressure in the suction chamber 142 extends to the first pressure chamber 412 and the second pressure chamber 491, and the pressure in the first pressure chamber 412 and the pressure in the second pressure chamber 491 are suctioned. It corresponds to the pressure in the chamber 142. The pressure in the first pressure chamber 412 is opposed to the pressure in the cylinders 451 and 442 and the spring force of the return spring 47 through the valve body 42. The pressure in the second pressure chamber 491 is opposed to the pressure in the cylinders 451 and 442 and the spring force of the return spring 47 through the oil and the valve body 42 in the volume variable chambers 521 and 511. Doing.

The spring force of the return spring 47 is to yield to the differential pressure generated between the pressure in the pressure chambers 412 and 491 and the pressure in the cylinders 451 and 442 when the fixed displacement piston type compressor 10 is operated. It is set. Therefore, when the fixed displacement piston type compressor 10 is operated, the differential pressure generated between the pressure in the pressure chambers 412 and 491 and the pressure in the cylinders 451 and 442 causes the spring force of the return spring 47 to decrease. In order to overcome this, the valve body 42 is moved from the blocking position shown in FIG. 3 to the communicating position shown in FIG. 4. The first movable end 512 of the first bellows 51 moves integrally with the valve body 42, and the first bellows 51 extends to increase the volume of the first volume variable chamber 511. . As the volume of the first variable volume chamber 511 increases, oil in the second variable volume chamber 521 is sucked into the first variable volume chamber 511 through the throttle passage 53.

When operation of the fixed displacement piston type compressor 10 is stopped, the refrigerant in the shaft passage 31 and the refrigerant in the cylinders 451 and 442 are sucked into the compression chamber 271 (see FIG. 1) and the compression chamber 281. The pressure in the in-axis passage 31 and in the cylinders 451 and 442 becomes high. Therefore, the pressure in the axial passage 31 and the cylinder 451, 442 and the pressure in the pressure chambers 412, 491 are balanced, and the valve body 42 is driven by the spring force of the return spring 47. It moves from the communicating position shown in FIG. 4 to the blocking position shown in FIG.

The valve body 42 has a suction chamber in the compressor in accordance with the elevation of the pressure in the introduction passage (inner shaft passage 31) corresponding to the operation state and the operation stop state of the fixed displacement piston compressor 10. 142 (suction pressure zone) and the outlets 312 and 313 of the introduction passages are switched to a position where they are in communication with and blocked. The valve body 42, the return spring 47, the partition wall plate 48, the first bellows 51, the second bellows 52, and the throttle passage 53 are the suction chamber 142 (suction pressure area) in the compressor. ) And switching means 61 capable of switching to a state in which the outlets 312 and 313 of the introduction passage communicate with each other. The valve body 42, the first bellows 51, the partition wall plate 48, and the second bellows 52 constituting the switching means 61 are serially moved from the rotation shaft 21 side to the lid 49 side in this order. Is arranged.

In the state of FIG. 3, the switching means 61 is in a state of blocking the outlet 312 (see FIG. 1), the outlet 313, and the suction chamber 142 of the introduction passage, and in the state of FIG. 4, The switching means 61 is in a state of communicating the outlet 312 (see FIG. 1) and the outlet 313 of the introduction passage with the suction chamber 142.

In the first embodiment, the following effects are obtained.

(1) When the operation of the fixed displacement piston type compressor 10 is started, the pressure in the shaft passage 31 and the cylinders 451 and 442 decreases, and the position communicates from the position at which the valve body 42 shuts off. Go to. When the valve body 42 moves from the position at which the valve body 42 shuts off, the position at which the inlet 441 is exposed to the suction chamber 142 increases. That is, the passage cross-sectional area between the suction chamber 142 and the cylinder 442 increases.

At the time of movement of the valve body 42 from the position to shut off, the volume of the first variable volume chamber 511 increases, so that the oil in the second variable volume chamber 521 passes through the throttle passage 53. Flows into the first variable volume chamber 511. The oil in the second variable volume chamber 521 flows through the throttle passage 53 and flows into the first variable volume chamber 511 to reduce the volume of the second variable volume chamber 521. The oil passing through the throttle passage 53 receives passage resistance by the throttle action of the throttle passage 53. This passage resistance slows the volume change of the 1st volume-variable chamber 511 and the 2nd volume-variable chamber 521, and the movement of the valve body 42 is braked. That is, the moving speed of the valve body 42 is suppressed low. Therefore, the change of the increase of the said passage cross-sectional area between the suction chamber 142 and the cylinder 442 is suppressed low, and refrigerant | coolant suction from the suction chamber 142 to the cylinder 442 is suppressed. As a result, starting shock is alleviated when the operation of the fixed displacement piston compressor 10 is started.

In addition, the amount of refrigerant compressed between the suction chamber 142 and the inlet port 441 in the fixed displacement piston compressor 10 is blocked (that is, in a position where the valve body 42 is blocked). There is little, and the effect of suppressing torque fluctuation, that is, the effect of reducing the starting shock is high.

(2) When the operation of the fixed displacement piston type compressor 10 is stopped, the valve body 42 returns to the cut-off position by the spring force of the return spring 47. The use of the return spring 47 is a simple structure in returning to the position which interrupt | blocks the valve body 42. FIG.

(3) The oil is a fluid which is very suitable for increasing the passage resistance in the throttle passage 53 and slowing down the moving speed of the valve body 42.

(4) The bellows 51 and 52 are very suitable for avoiding oil leakage from the first volume variable chamber 511 and the second volume variable chamber 521.

(5) As the distance that the valve body 42 moves from the blocking position shown in FIG. 3 to the communicating position shown in FIG. 4 increases, the passage cross-sectional area between the suction chamber 142 and the cylinder 442 is increased. The change of increase can be suppressed low. That is, it is advantageous to make the moving distance as large as possible in increasing the effect of mitigation shock.

When the volume change is the same size, the moving distance of the first movable end 512 of the first bellows 51 is made larger than the moving distance of the second movable end 522 of the second bellows 52. Such a configuration is very suitable for cutting the moving distance of the valve body 42 while minimizing the size of the lid 49 (reducing the direction of the rotation axis 210).

(6) When the inlet 441, which is the inlet of the cylinder 442 of the valve body 42, enters the cylinder 411 and is shielded when the valve body 42 is in a position to be blocked, the valve body 42 Is in the communication position, it is exposed in the suction chamber 142 outside the cylinder 411. The configuration in which the introduction port 441 enters and exits the inside of the cylinder 411 is very suitable for increasing the introduction port 441 to secure a sufficient passage cross-sectional area of the introduction passage.

Next, the second embodiment of Figs. 5 (a) and 5 (b) will be described. The same code | symbol is used for the same structural part as 1st Embodiment.

A communication chamber 62 and a valve hole 631 are formed in the rear housing 14, and a plate-shaped opening / closing plate 64 can open and close the valve hole 631 in the communication chamber 62. It is accepted. The valve hole 631 is formed through the partition 63 which divides the communication chamber 62 and the suction chamber 142. The inlet 311 of the in-axis passage 31 opens to the communication chamber 62 in the rear housing 14 in the cross section 213 of the rotating shaft 21 in the cylinder block 12.

The piston 65 is fitted in the cylinder 411, and the transmission rod 66 is integrally formed in the piston 65. As shown in FIG. An opening and closing plate 64 is attached to the tip of the transfer rod 66. The plane valve seat surface 632 is formed in the surface of the partition 63 on the side of the connection chamber 62, and the opening / closing plate 64 is in contact with and separated from the valve seat surface 632. The sealing surface 641 of the opening / closing plate 64 in contact with the valve seat surface 632 is formed flat. That is, when the open / close plate 64 closes the valve hole 631, the seal surface 641 of the open / close plate 64 is in surface contact with the valve seat surface 632. The piston 65, the transmission rod 66, and the opening / closing plate 64 constitute a valve body 67 that opens and closes the valve hole 631, and the valve body 67 has a first volume in the cylinder 411. The variable chamber 413 is partitioned. The first volume variable chamber 413 communicates with the second volume variable chamber 521 through the throttle passage 53.

The volume of the first variable volume chamber 413 partitioned by the piston 65 as the first chamber forming member is a positional displacement of the piston 65 as the first movable portion (position displacement in the direction of the rotation axis 210). To change. That is, the 1st volume-variable chamber 413 changes a volume according to the positional displacement of the valve body 67 (position displacement in the direction of the rotation axis 210).

The return spring 68 is interposed between the piston 65 and the partition 63. The return spring 68 elastically supports in the direction which pushes the piston 65 into the cylinder 411. In FIG. 5 (b), the valve body 67 opens the valve hole 631 to communicate with the communication chamber 62 and the suction chamber 142. In FIG. 5 (a), the valve body 67 is a valve. The ball 631 is closed to block the communication between the communication chamber 62 and the suction chamber 142. The return spring 68 elastically supports the valve body 67 from the position at which the valve body 67 is in communication with the return spring 68.

A plurality of stoppers 642 protrude from the rear surface of the opening / closing plate 64 opposite to the end face 213 of the rotating shaft 21. The stopper 642 is in contact with and detachable from the tip of the cylindrical portion 123 protruding from the end face 122 of the cylinder block 12. In the state where the valve body 67 is disposed at the communicating position shown in Fig. 5 (b), the stopper 642 abuts against the tip of the cylinder portion 123, and the valve body 67 is shown in Fig. 5 (a). In the state where it is arrange | positioned at the position to cut off shown in the figure, the stopper 642 is separated from the front-end | tip of the cylinder part 123. FIG.

When the fixed displacement piston type compressor 10 is in the stopped state, the valve body 67 is arranged at a position to be cut off shown in Fig. 5A by the spring force of the return spring 68, The refrigerant in 142 cannot enter the communication chamber 62. When the operation of the fixed displacement piston type compressor 10 starts, the refrigerant in the shaft passage 31 and the refrigerant in the communication chamber 62 are sucked into the compression chamber 271 (see FIG. 1) and the compression chamber 281. Therefore, the pressure in the in-axis passage 31 and the communication chamber 62 is lowered by this suction action. That is, the pressure in the in-axis passage 31 and the communication chamber 62 is lower than the pressure in the suction chamber 142. Therefore, the valve body 67 is arrange | positioned in the communication position shown in FIG. 5 (b), and the refrigerant | coolant in the suction chamber 142 passes through the valve hole 631, the communication chamber 62, and the in-axis passage 31. Therefore, as shown in FIG. The process then flows into the compression chamber 271 (see Fig. 1) and the compression chamber 281.

The valve body 67, the return spring 68, the partition wall plate 48, the bellows 52, and the throttle passage 53 include the suction chamber 142 (suction pressure area) and the outlet 312, A switching means 61A capable of switching to the state of communicating 313 and the state of blocking is constituted.

Also in the second embodiment, an alleviation effect of starting shock is obtained. In addition, since the volume of the communication chamber 62 accommodating the plate-shaped opening and closing plate 64 can be made small, similar to the case of the first embodiment, the relaxation effect of the starting shock is high.

Next, the third embodiment of FIGS. 6 and 7 will be described. The same code | symbol is used for the same structural part as 2nd Embodiment.

The piston 69 is slidably fitted in the cylinder 41, and the first movable end 512 of the first bellows 51 is attached to the piston 69. The piston 69 partitions the first pressure chamber 412 into the cylinder 411.

The transfer rod 70 is connected to the piston 69. The transmission rod 70 enters in the in-axis passageway 31A. The in-axis passage 31A includes a small diameter passage 314 and a larger diameter passage 315 that is larger than the small diameter passage 314. The disc 71 is attached to the front-end | tip of the transmission rod 70 in the small diameter passage 314, and the cylindrical columnar body 72 is attached to the transmission rod 70 in the large diameter passage 315. As shown in FIG.

The disk 71 is fitted in the small-diameter passage 314 so as to be slidable in the direction of the rotation axis 210 of the rotation shaft 21, and the cylindrical cylindrical face 72 is a rotation axis of the rotation shaft 21. The outlet 313 is slidable in the direction of 210 and is fitted in the large diameter passage 315 so that opening and closing is possible. The cylinder of the cylindrical columnar body 72 has an in-axis passage 31A between the disc 71 and the cylinder body 72, and an inlet 311 and the cylindrical surface 72 of the in-axis passage 31A. 31A of in-axis passages are communicated.

 As shown in Fig. 7, when the circumferential body 72 is in a position to close the outlet 313, the disc 71 is located upstream than the outlet 312 in the in-axis passage 31A, and the in-axis passage ( The refrigerant of 31A cannot enter the compression chamber 271 through the outlet 312. As shown in Fig. 6, when the circumferential body 72 is in a position to open the outlet 313, the disc 71 is located downstream from the outlet 312 in the in-axis passage 31A, and the in-axis passage ( A refrigerant of 31A can flow into the compression chamber 271 through the outlet 312.

A return spring 73 is interposed between the step 316 between the small-diameter passage 314 and the large-diameter passage 315 and the circumferential surface 72. The return spring 73 pushes the piston 69 into the cylinder 411 so that the entirety of the disk 71, the circumferential body 72, the transfer rod 70, and the piston 69 is the first pressure chamber 412. It is elastically supported toward).

When the fixed displacement piston type compressor 10 is in the stopped state, the disc 71 and the circumferential body 72 are held at the blocking position shown in FIG. 7 by the spring force of the return spring 73. When the operation of the fixed displacement piston type compressor 10 starts, the refrigerant in the space 317 (part of the shaft passage 31A) between the disc 71 and the end of the shaft shaft 31A is The suction in the compression chamber 271 lowers the pressure in the space 317. Therefore, the disc 71 and the columnar body 72 are arrange | positioned from the blocking position shown in FIG. 7 to the communicating position shown in FIG. 6 with respect to the spring force of the return spring 73. FIG. When the operation of the fixed displacement piston type compressor 10 is stopped, the disc 71 and the circumferential surface 72 return to the blocking position shown in Fig. 7 by the spring force of the return spring 73. The disc 71, the circumferential body 72, the transfer rod 70, and the piston 69 constitute a valve body that partitions the first pressure chamber 412 into the cylinder 411.

The valve element is operated in the compressor according to the height of the pressure in the space 317 (part of the introduction passage (internal shaft passage 31A)) corresponding to the operation state and the operation stop state of the fixed displacement piston compressor 10. The suction chamber 142 (suction pressure area) and the outlets 312 and 313 of the introduction passage are switched to a position where they are in communication with and blocked. The valve body, the partition wall plate 48, the first bellows 51, the second bellows 52 and the throttle passage 53 are the suction chamber 142 (suction pressure area) and the outlet 312 of the introduction passage in the compressor. And 313, the switching means 61B capable of switching to a state of communicating and blocking.

In 3rd Embodiment, the same effect as 2nd Embodiment is acquired. In the third embodiment, the refrigerant that can be sucked into the compression chambers 271 and 281 when the disc 71 and the circumferential body 72 are in a position to be blocked is in the spaces 317 and the outlets 312 and 313. Since only the refrigerant in the internal and communication paths 32 and 33 are used, the relaxation effect of the starting shock is higher than that in the first and second embodiments.

Moreover, if it is set as the structure which can rotate relatively between the piston 69 and the transmission rod 70, the relative rotation between the return spring 73 and the rotating shaft 21 can be prevented, and the return spring 73 Wear damage of the return spring 73 or the rotary shaft 21 due to relative rotation between the rotary shaft 21 and the rotary shaft 21 can be avoided. Alternatively, the configuration may be configured to be relatively rotatable between the circumferential surface 72 and the return spring 73.

Next, the fourth embodiment of Figs. 8 (a) and 8 (b) will be described. The same code | symbol is used for the same structural part as 3rd Embodiment.

A piston 69 is fitted into the cylinder 411, and the piston 69 partitions the first volume variable chamber 413 into the cylinder 411. The volume of the first variable volume chamber 413 defined by the piston 69 as the first chamber forming member is a positional displacement (position displacement in the direction of the rotation axis 210) of the piston 69 as the first movable portion. Change by).

The first volume variable chamber 413 communicates with the second volume variable chamber 521 through the throttle passage 53. The moving distance of the piston 69 when the volume change in the first volume variable chamber 413 and the volume change in the second volume variable chamber 521 are the same size is the second movable end 522 of the second bellows 52. ) To be larger than the moving distance.

When the fixed displacement piston type compressor 10 is in the stopped state, the cylinder 75 is held in the blocking position shown in Fig. 8A by the spring force of the return spring 73. When the operation of the fixed displacement piston type compressor 10 is started, the cylinder 75 resists the spring force of the return spring 73 to communicate with the cylinder shown in Fig. 8B from the blocking position shown in Fig. 8A. Is placed in a position to. The disc 71, the circumferential body 72, the transmission rod 70, and the piston 69 comprise the valve body which partitions the 1st volume variable chamber 413 in the cylinder 411. As shown in FIG. The valve body, the partition wall plate 48, the bellows 52, and the throttle passage 53 communicate with and disconnect the state in which the suction chamber 142 (suction pressure area) in the compressor communicates with the outlets 312 and 313 of the introduction passage. The switching means 61C which can switch to the state to be made is comprised.

In 4th Embodiment, the same effect as 3rd Embodiment is acquired.

Next, the fifth embodiment of Figs. 9 (a) and 9 (b) will be described. The same code | symbol is used for the same structural part as 4th Embodiment.

The cylinder 75 is connected to the piston 69 so that relative rotation is possible with respect to the piston 69. The cylinder 75 is slidably fitted into the in-axis passageway 31A. An end wall 752 is formed at the tip of the cylinder 75. Angular pins 76 are attached to the inner end of the shaft passage 31A and the pins 76 are relative to the end wall 752 of the barrel 75. It is slidably inserted. The cylinder 75 and the square pin 76 rotate integrally with the rotating shaft 21, and can slide inside the shaft passage 31A in a state where the square pin 76 is inserted through the end wall 752. The piston 69 and the cylinder 75 comprise the valve body which partitions the 1st volume variable chamber 413 in the cylinder 411.

The cylinder 75 is equipped with the small diameter cylinder part 77 inserted into the small diameter passage 314, and the large diameter cylinder part 78 fitted into the large diameter passage 315. As shown in FIG. In the large diameter cylinder portion 78 in the suction chamber 142, an introduction port 751 is formed so as to communicate the suction chamber 142 with the cylinder 750 of the cylinder 75. A return spring 74 is interposed between the step 753 between the small-diameter cylindrical portion 77 and the large-diameter cylindrical portion 78 and the step 316 on the rotating shaft 21 side. The return spring 74 elastically supports the cylinder 75 toward the partition wall plate 48 as the piston 69 is pushed into the cylinder 411.

The small-diameter tubular part 77 in the small-diameter passage 314 is formed so that the cylinder port 771 may communicate with the small-diameter tubular part 77, and the large-diameter tubular part 78 may communicate with the large-diameter tubular part 78 in the large diameter tubular part 78. Formed.

The piston 79 is slidably accommodated in the second pressure chamber 491. The piston 79 partitions the second volume variable chamber 492 in the second pressure chamber 491. The volume of the second variable volume chamber 492 partitioned by the piston 79 as the first chamber forming member is a positional displacement (position displacement in the direction of the rotation axis 210) of the piston 79 as the second movable portion. To change. That is, the 1st volume-variable chamber 413 changes a volume according to the positional displacement (position displacement in the direction of the rotation axis 210) of the said valve body which partitions the 1st volume-variable chamber 413. FIG.

The second volume variable chamber 492 communicates with the first volume variable chamber 413 through the throttle passage 53, and the second pressure chamber 491 communicates with the suction chamber 142 through the passage 80. Communicating with The diameter of the piston 79 is larger than the diameter of the piston 69. Therefore, the movement distance of the piston 69 is larger than the movement distance of the piston 79 when the volume change in the first volume variable chamber 413 and the volume change in the second volume variable chamber 492 are the same size.

The valve body, the partition wall plate 48, the throttle passage 53, and the piston 79 that partition the first volume variable chamber 413 in the cylinder 411 are the suction chamber 142 (suction pressure area) in the compressor. And the switching means 61D which can switch to the state which communicates the exit 312,313 of the introduction passage, and the state which interrupt | blocks.

9B shows a state in which the small-diameter cylindrical portion 77 as the valve body closes the outlet 312, and a state in which the large-diameter cylindrical portion 78 as the valve body closes the outlet 313. As a result, communication between the outlets 312 and 313 and the cylinder 750 of the cylinder 75 is blocked. Fig. 9A shows a state in which the vent 771 and the outlet 312 of the small diameter cylindrical portion 77 communicate with each other, and the passage 781 and the outlet 313 of the large diameter cylindrical portion 78 communicate with each other. The outlets 312 and 313 and the cylinder 750 communicate with each other. The refrigerant in the suction chamber 142 can flow into the compression chamber 271 through the inlet 751, the cylinder 750, the cylinder 771, the outlet 312, and the communication path 32. The refrigerant of 142 can flow into the compression chamber 281 through the inlet port 751, the cylinder 750, the cylinder port 781, the outlet 313, and the communication path 33.

As shown in Fig. 9B, when the cylinder 75 is in the position where the outlets 312 and 313 are closed, the tip of the cylinder 75 is upstream than the outlet 312 in the in-axis passage 31A. In this case, the refrigerant in the shaft passage 31A cannot flow into the compression chamber 271 through the outlet 312. As shown in Fig. 9B, when the cylinder 75 is in the position to open the outlets 312 and 313, the tip of the cylinder 75 is downstream from the outlet 312 in the in-axis passage 31A. In this case, the refrigerant in the shaft passage 31A can flow into the compression chamber 271 through the outlet 312.

When the fixed displacement piston type compressor 10 is in the stopped state, the cylinder 75 is held in the blocking position shown in Fig. 9B by the spring force of the return spring 74. When the operation of the fixed displacement piston type compressor 10 starts, the refrigerant in the space 317 (part of the shaft passage 31A) between the tip of the cylinder 75 and the end of the shaft shaft 31A is compressed. The suction in the chamber 271 lowers the pressure in the space 317. Therefore, the cylinder 75 is arrange | positioned in the position which communicates in FIG. 9 (a) from the position cut off shown in FIG. 9 (b) with respect to the spring force of the return spring 74. FIG.

The valve body constituted by the piston 69 and the cylinder 75 includes a space 317 (induction passage (internal shaft passage 31A) corresponding to the operation state and the operation stop state of the fixed displacement piston compressor 10. In accordance with the height of the pressure in the part, the suction chamber 142 (suction pressure area) in the compressor and the outlets 312 and 313 of the introduction passages are switched to a position where the communication with the position is blocked.

In the fifth embodiment, the same effects as in the fourth embodiment can be obtained.

Next, the sixth embodiment of FIG. 10 will be described. The same code | symbol is used for the same structural part as 1st Embodiment.

The entire housing of the fixed displacement piston type compressor 10A is composed of a cylinder block 12, a front housing 13, and a rear housing 14, and between the cylinder block 12 and the front housing 13. The swash plate 23 is housed in the swash plate chamber 24. The single headed piston 81 associated with the swash plate 23 reciprocates in the cylinder bore 28 as the swash plate 23 rotates. The rotary valve 21 is provided with a rotary valve 36 corresponding to the cylinder block 12, and the rear housing 14 has a valve body 42, a partition wall plate 48, a first bellows 51 and a second. The bellows 52 is formed.

In the sixth embodiment, the same effects as in the first embodiment can be obtained.

In the present invention, the following embodiments are also possible.

In the fifth embodiment, the bellows 51 in the first embodiment may be used instead of the piston 69.

The first rotary valve 35 and the second rotary valve 36 may be formed separately from the rotary shaft 21.

The partition wall may be integrated with the rear housing (a part of the rear housing also serves as the partition wall).

1 is a side sectional view of an entire compressor showing a first embodiment.

FIG. 2A is a cross-sectional view taken along the line A-A of FIG. 1, and FIG. 2B is a cross-sectional view taken along the line B-B of FIG.

3 is a partially enlarged side cross-sectional view.

4 is a partially enlarged side sectional view.

5 (a) and 5 (b) are partial enlarged side cross-sectional views showing the second embodiment.

Fig. 6 is a side sectional view of the entire compressor showing the third embodiment.

7 is a side cross-sectional view of the entire compressor.

8 (a) and 8 (b) are partial side cross-sectional views showing the fourth embodiment.

9 (a) and 9 (b) are partial side cross-sectional views showing the fifth embodiment.

Fig. 10 is a side sectional view of the entire compressor showing the sixth embodiment.

(Explanation of symbols for the main parts of the drawing)

10, 10A: fixed displacement piston compressor

11, 12: cylinder block

111, 121: shaft hole as a valve receiving chamber

131 and 141: discharge chamber as discharge pressure region

14: rear housing

142: suction chamber as suction pressure region in the compressor

21: rotating shaft

210: axis of rotation

211, 212: seal

213: cross section

23: swash plate as a cam body

25: electronic clutch

26: vehicle engine as an external drive source

27, 28: Cylinder Bore

271, 281: compression chamber

29: double head piston

31, 31A: In-axis passage which constitutes the introduction passage

311: entrance

312, 313: exit

35: first rotary valve

36: second rotary valve

413: first volumetric variable chamber

42, 67: valve body constituting the switching means

441: Inlet port as entrance of inner passage

442: inside as a passageway

47, 73, 74: return spring

48: partition wall plate as partition wall

492 second volume variable chamber

51: first bellows as the first chamber forming member

511: first volume variable chamber

512: first movable end as the first movable part

52: second bellows as second chamber forming member

521: second volume variable chamber

522: second movable end as the second movable part

53: throttle passage

61, 61A, 61B, 61C, 61D: switching means

71: disc constituting the valve body

72: circumferential surface constituting the valve body

75: barrel constituting the valve body

81: migraine piston

Claims (9)

A piston is accommodated in a plurality of cylinder bores arranged around the rotation shaft, the piston being linked to the rotation of the rotation shaft through a cam body integrated with the rotation shaft, and partitioned in the cylinder bore by the piston. (define) a rotary valve having an introduction passage for introducing refrigerant from the suction pressure region to the compression chamber, the rotary valve is integrally rotated with the rotary shaft, the rotary shaft through the clutch to the external drive source In the refrigerant suction structure in the fixed displacement piston-type compressor to be connected, Switching means for switching between a suction pressure region in the compressor and a state in which the outlet of the inlet passage is in communication with the outlet is formed, and the switching means communicates the suction pressure region in the compressor with the outlet of the inlet passage. A valve body which is arranged to be switched to a position to shut off and a position to shut off; And a second volume variable chamber capable of volume change, and an throttle passage communicating the first volume variable chamber and the second volume variable chamber, wherein the first volume variable chamber and the second volume variable chamber are filled with fluid. In the fixed displacement piston compressor, when the first volume variable chamber changes in volume, the fluid passes through the throttle passage. Intake structure. The method of claim 1, The first volume variable chamber is formed between the partition wall and the first chamber forming member having the first movable portion that is displaced, and the second volume variable chamber is the partition wall and the second movable positionally displaced. It is formed between the 2nd chamber formation member which has a part, The said throttle passage communicates with the said 1st volume variable chamber and the said 2nd volume variable chamber through the said partition wall, A volume is changed by the positional displacement of the said 1st movable part, and the volume of the said 2nd volume variable chamber changes with the positional displacement of the said 2nd movable part. The refrigerant suction structure in the fixed displacement piston type compressor. The method of claim 2, The first chamber forming member is a first bellows connected to the partition wall, the second chamber forming member is a second bellows connected to the partition wall, and the first movable portion is a movable end of the first bellows. The second movable part is a refrigerant suction structure in a fixed displacement piston compressor, which is a movable end of the second bellows. The method of claim 3, The valve body is a refrigerant suction structure in a fixed displacement piston-type compressor attached to a movable end of the first bellows. The method of claim 3, A refrigerant suction structure in a fixed displacement piston type compressor having a moving distance of the movable end of the first bellows when the volume change is the same size is larger than a moving distance of the movable end of the second bellows. The method of claim 1, The fluid is a refrigerant suction structure in a fixed displacement piston compressor. The method according to any one of claims 1 to 6, And the valve body is disposed at a position at which the inlet of the introduction passage is blocked from the suction pressure region in the compressor when the switching means is in the blocking state. The method according to any one of claims 1 to 6, The introduction passage has an inlet at the end face of the rotary valve, an outlet at a main surface of the rotary valve, and the introduction passage has an in-axis passage extending in the direction of the rotation axis of the rotation shaft inside the rotation shaft. The outlet of the introduction passage penetrates through the main surface of the rotation shaft to communicate with the in-axis passage, and the valve body slides in the introduction passage from the inlet of the introduction passage in the direction of the rotation axis. The valve body is inserted into the valve shaft, and the valve body moves in the direction of the rotation axis to be switched to the communicating position and the blocking position, and the blocking position is such that the valve body is separated from the shaft passage. Refrigerant suction in a fixed displacement piston compressor, which is a position to block an outlet of the introduction passage. Structure. The method according to any one of claims 1 to 6, A rear housing is connected to a cylinder block forming the cylinder bore, a suction chamber is formed in the rear housing, and the valve body is a refrigerant in a fixed displacement piston compressor formed in the rear housing. Suction structure.

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