JP3254820B2 - Clutchless one-sided piston type variable displacement compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention supplies pressure in a discharge pressure area to a crank chamber through a pressure supply passage connecting the discharge pressure area and the crank chamber, and connects the crank chamber to the suction pressure area. The present invention relates to a clutchless one-sided piston type variable displacement compressor that regulates pressure in a crank chamber by releasing pressure in a crank chamber to a suction pressure region through a pressure release passage.

[0002]

2. Description of the Related Art In a variable displacement type swash plate type compressor disclosed in Japanese Patent Application Laid-Open No. 3-37378, an electromagnetic clutch is provided for connecting and disconnecting power transmission between an external drive source and a rotary shaft of the compressor. Not used. Eliminating the electromagnetic clutch can eliminate the drawback of poor physical feeling due to the ON-OFF shock particularly in a vehicle-mounted configuration, and can reduce the weight and cost of the entire compressor.

[0003] In such a clutchless compressor, there is a problem that the discharge capacity is small when cooling is not required, and that frost is generated in the evaporator on the external refrigerant circuit. When cooling is unnecessary or when frost may occur, the circulation of the refrigerant on the external refrigerant circuit may be stopped. In the compressor disclosed in JP-A-3-37378, the refrigerant gas from the external refrigerant circuit to the suction chamber is stopped to stop the circulation of the refrigerant on the external refrigerant circuit. When the refrigerant gas flow is stopped, the pressure in the suction chamber decreases,
The capacity control valve responsive to the suction chamber pressure is fully opened. With this full opening, the refrigerant gas discharged from the discharge chamber flows into the crank chamber,
The pressure in the crankcase increases. Further, the suction pressure in the cylinder bore also decreases due to a decrease in the pressure of the suction chamber. for that reason,
The difference between the pressure in the crank chamber and the suction pressure in the cylinder bore increases, so that the swash plate tilt shifts to the minimum tilt and the discharge capacity becomes the minimum. When the discharge capacity is minimized, the torque in the compressor is minimized, and power loss when cooling is unnecessary can be avoided.

[0004]

The stop of the flow of the refrigerant gas from the external refrigerant circuit to the suction chamber in the compressor is performed by closing the electromagnetic on-off valve. The operation of the solenoid on-off valve is an ON-OFF operation, and the flow of refrigerant gas from the external refrigerant circuit to the suction chamber in the compressor is stopped instantaneously. Therefore, the amount of the refrigerant gas sucked into the cylinder bore from the suction chamber is sharply reduced. A sudden decrease in the amount of refrigerant gas sucked into the cylinder bore results in a sudden decrease in the discharge capacity, and a sudden drop in the discharge pressure. As a result, the torque in the compressor varies greatly in a short time.

The flow of the refrigerant gas from the external refrigerant circuit to the suction chamber in the compressor is also restarted instantaneously. Therefore, the amount of the refrigerant gas sucked from the suction chamber into the cylinder bore rapidly increases. A sudden increase in the amount of refrigerant gas sucked into the cylinder bore results in a sudden increase in the discharge capacity, and a sudden increase in the discharge pressure. As a result, the torque in the compressor varies greatly in a short time.

[0006] The occurrence of such large torque fluctuations is contrary to the alleviation of the ON-OFF shock, which is the main purpose of making the compressor clutchless. The present invention suppresses torque fluctuations in a clutchless one-sided piston type variable displacement compressor by using a mechanism for gradually reducing or increasing the flow of refrigerant gas from an external refrigerant circuit to a suction chamber, and reducing the flow of refrigerant gas. An object of the present invention is to secure a smooth operation of a mechanism that squeezes or increases.

[0007]

According to the present invention, there is provided:
Crank chamber, a suction chamber, a discharge chamber and a cylinder bore connecting to each of these chambers is partitioned and formed, a single-headed piston rotatably supporting the upper rotating shaft in a housing reciprocally linearly movably received in the cylinder bores, rotating Secure the rotating support to the shaft
Rutotomoni, swash plate and tiltably linked to the rotation support, controls the inclination angle of the swash plate by the difference through a single-headed piston between the pressure and the suction pressure of the crank chamber, connects the discharge pressure zone to the crank chamber supplies pressure in the discharge pressure region through the supply passage to the crank chamber to, the pressure supply is controlled by capacity control valve, the crank chamber through the pressure passage releasing connects the crank chamber and the suction pressure zone The invention according to claim 1 is directed to a clutchless one-sided piston type variable displacement compressor that discharges the pressure to the suction pressure region to regulate the pressure in the crank chamber.
The shutoff body is slidable and relatively rotatable on the rotating shaft so as to be switchable between a closed position for closing a suction passage for introducing refrigerant gas from an external refrigerant circuit to the suction chamber and an open position for opening the suction passage. supported on, least <br/> rather as a part of the inclination angle of the swash plate is interlocked with sliding of the blocking body, the inclination angle of the swash plate when the blocking member is in the closed position and the minimum inclination angle
And the release forms part of the pressure passage into sliding contact area between the rotary shaft and the blocking member, the outlet of the pressure passage releasing the downstream of the shut-off position on the suction passage which is blocked by the blocking member Set.

According to the second aspect of the present invention, the pressure release passage is formed in a rotary shaft, and an inlet of the pressure release passage is opened to the crank chamber near a lip seal for sealing a peripheral surface of the rotary shaft. Was.

[0009]

SUMMARY OF minimum inclination angle is the inclination angle of the inclined plate by the step-up in the crank chamber
As the migrating into the blocking member moves before Ki閉position. As the shut-off body approaches the closed position, the passage cross-sectional area of the refrigerant gas flowing into the suction chamber from the external refrigerant circuit gradually narrows. This throttle action mitigates a decrease in the amount of refrigerant gas flowing into the suction chamber from the external refrigerant circuit. Therefore, the amount of refrigerant gas sucked from the suction chamber into the cylinder bore also gradually decreases, and the discharge capacity does not suddenly fluctuate toward the minimum capacity.
As a result, the torque in the compressor does not fluctuate rapidly in a short time.

[0010] As the swash plate inclination angle by the pressure drop in the crank chamber increases from the minimum inclination, blocking member moves from the pre Ki閉position to the open position. As the breaker moves away from the closed position, the cross-sectional area of the refrigerant gas passing from the external refrigerant circuit to the suction chamber gradually increases. This gradually increasing cross-sectional area of the passage mitigates an increase in the amount of refrigerant gas flowing into the suction chamber from the external refrigerant circuit. Accordingly, the refrigerant gas suction amount from the suction chamber into the cylinder bore also increases slowly, and the discharge capacity does not fluctuate toward the maximum capacity side. As a result, the torque in the compressor does not fluctuate rapidly in a short time.

When the shutoff is in the open position, the refrigerant gas in the crank chamber flows to the suction chamber via the pressure release passage. When the shutoff is in the closed position, the refrigerant gas in the discharge chamber returns to the discharge chamber via the pressure supply passage, the crank chamber, the pressure release passage, the suction chamber, and the cylinder bore. A part of the pressure release passage is in a sliding contact area between the rotating shaft and the blocking body, and the sliding contact area is lubricated by the lubricating oil that moves together with the refrigerant gas.

If the inlet of the pressure release passage in the rotary shaft is opened near the lip seal, the sealing performance of the lip seal is improved.

[0013]

FIG. 1 shows a first embodiment of the present invention.
This will be described with reference to FIG. As shown in FIG. 1, a front housing 2 is joined to a front end of a cylinder block 1 which is a part of a housing of the entire compressor. A rear housing 3 is joined and fixed to the rear end of the cylinder block 1 via a valve plate 4, valve forming plates 5A and 5B, and a retainer forming plate 6. A deep groove ball bearing member 7 is mounted in the front housing 2.
A rotating support 8 is supported on the deep groove ball bearing member 7, and a rotating shaft 9 is fixed to the rotating support 8. The deep groove ball bearing member 7 receives both the load in the thrust direction and the load in the radial direction acting on the rotating shaft 9 via the rotating support 8.

The front end of the rotating shaft 9 projects outside from the crank chamber 2a via the front housing 2, and a pulley 10 is screwed to this projected end. The pulley 10 is operatively connected to a vehicle engine via a belt 11. A lip seal 12 is interposed between the front end of the rotating shaft 9 and the front housing 2. Lip seal 1
2 prevents pressure leakage in the crank chamber 2a.

A swash plate support 14 having a spherical shape is slidably supported on the rotating shaft 9, and a swash plate 15 is supported on the swash plate support 14 so as to be tiltable in the axial direction of the rotating shaft 9. . Connecting pieces 16 and 17 are fixed to the swash plate 15.
As shown in FIG. 2, a pair of guide pins 18 and 19 are fixed to the connecting pieces 16 and 17. A support arm 8a protrudes from the rotary support 8. A support pin 20 is rotatably supported by the support arm 8a and penetrates in a direction perpendicular to the rotation shaft 9. A pair of guide pins 18 and 19
Are slidably fitted into both ends of the support pin 20. The swash plate 15 is connected to the swash plate support 14 by the cooperation of the support pin 20 on the support arm 8a and the pair of guide pins 18 and 19.
Can be tilted in the axial direction of the rotating shaft 9 around the center and can be rotated integrally with the rotating shaft 9. The tilt of the swash plate 15 is determined by the slide guide relationship between the support pin 20 and the guide pins 18 and 19,
The guide is guided by the sliding action of the swash plate support 14 and the support action of the swash plate support 14.

As shown in FIGS. 1, 5 and 6, a housing hole 13 is provided in the center of the cylinder block 1 in the axial direction of the rotary shaft 9, and a cylindrical blocking member is provided in the housing hole 13. Body 2
1 is slidably accommodated. The blocking body 21 includes a large diameter portion 21a and a small diameter portion 21b. A suction passage opening spring 36 is provided between the step portion 21c on the outer peripheral surface of the blocking member 21 and the flange portion 13a on the inner peripheral surface of the housing hole 13. Intervened. The suction passage opening spring 36 connects the blocking body 21 to the swash plate support 1.
It is biased to the 4 side.

The rear end of the rotating shaft 9 is inserted into the large diameter portion 21a of the blocking body 21. A ball 41 is pressed against the rear end of the rotating shaft 9 by the spring force of a spring 42. Spring 4
Reference numeral 2 serves to suppress the displacement of the rotating shaft 9 in the thrust direction.

A deep groove ball bearing member 53 is interposed between the rear end of the rotating shaft 9 and the inner peripheral surface of the large diameter portion 21a. The rear end of the rotating shaft 9 is provided with a deep groove ball bearing member 53 and a blocking body 21.
And is supported by the inner peripheral surface of the housing hole 13. The outer ring 53a of the deep groove ball bearing member 53 is fixed to the inner peripheral surface of the large diameter portion 21a, and the inner ring 53b can slide on the peripheral surface of the rotating shaft 9. As shown in FIG. 5, a step 9a is formed on the peripheral surface of the rear end of the rotating shaft 9, and the inner race 53b is connected to the step 9
The movement toward the swash plate support 14 is restricted by a. That is, the deep groove ball bearing member 53 is prevented from moving toward the swash plate support 14 by the step 9a. Therefore, when the deep groove ball bearing member 53 comes into contact with the step portion 9a, the blocking member 2
1 is prevented from moving toward the swash plate support 14 side.

A suction passage 5 is provided at the center of the rear housing 3.
4 are formed. The suction passage 54 communicates with the housing hole 13, and a positioning surface 55 is formed around the opening of the suction passage 54 on the housing hole 13 side. The distal end of the small-diameter portion 21 b of the blocking body 21 can contact the positioning surface 55. When the distal end of the small diameter portion 21b contacts the positioning surface 55, the movement of the blocking body 21 in the direction away from the swash plate support 14 is restricted, and the communication between the suction passage 54 and the housing hole 13 is blocked. .

Swash plate support 14 and deep groove ball bearing member 53
A transmission cylinder 56 is interposed slidably on the rotating shaft 9 between the first and second transmission cylinders. One end of the transmission cylinder 56 can contact the end face of the swash plate support 14, and the other end of the transmission cylinder 56 can contact only the inner ring 53 b without contacting the outer ring 53 a of the deep groove ball bearing member 53.

As the swash plate support 14 moves toward the blocking body 21, the blocking body 21 comes into contact with the transmission cylinder 56,
To the inner ring 53b of the deep groove ball bearing member 53. The deep groove ball bearing member 53 receives not only a load in the radial direction but also a load in the thrust direction of the rotating shaft 9. Therefore, the blocking body 2
Reference numeral 1 denotes a suction passage opening spring 36 by a pressing action of the transmission cylinder 56.
And the distal end of the small diameter portion 21b abuts on the positioning surface 55. Therefore, the minimum inclination angle of the swash plate 15 is regulated by the contact between the tip of the small diameter portion 21 b of the blocking body 21 and the positioning surface 55. Swash plate 15
Is slightly larger than 0 °. This minimum inclination state is brought about when the blocking body 21 is disposed at the closed position where the communication between the suction passage 54 and the accommodation hole 13 is blocked, and the blocking body 21 is moved between the closed position and the open position separated from this position. The swash plate support 14 is interlocked and switched.

The maximum inclination angle of the swash plate 15 is regulated by the contact between the inclination regulating protrusion 8 b of the rotary support 8 and the swash plate 15.
A single-headed piston 22 is accommodated in a cylinder bore 1a penetrating through the cylinder block 1 so as to be connected to the crank chamber 2a. A pair of shoes 23 is fitted into the neck 22a of the single-headed piston 22. The peripheral portion of the swash plate 15 enters between the two shoes 23, and both end surfaces of the two shoes 23 contact both surfaces of the swash plate 15. Accordingly, the rotational movement of the swash plate 15 is converted into the reciprocating swing of the single-headed piston 22 via the shoe 23, and the single-headed piston 22 moves back and forth in the cylinder bore 1a.

As shown in FIGS. 1 and 3, a suction chamber 3a and a discharge chamber 3b are defined in the rear housing 3. A suction port 4a and a discharge port 4b are formed on the valve plate 4. A suction valve 5a is formed on the valve forming plate 5A, and a discharge valve 5b is formed on the valve forming plate 5B. Refrigerant gas in the suction chamber 3a is supplied to the suction port 4a by the reciprocating operation of the single-headed piston 22.
, The suction valve 5a is pushed away and flows into the cylinder bore 1a. The refrigerant gas that has flowed into the cylinder bore 1a is discharged to the discharge chamber 3b by pushing the discharge valve 5b out of the discharge port 4b by the forward movement of the single-headed piston 22. Discharge valve 5b
Abuts on the retainer 6 a on the retainer forming plate 6 to regulate the opening.

The stroke of the single-headed piston 22 changes according to the pressure difference between the pressure in the crank chamber 2a and the suction pressure in the cylinder bore 1a through the single-headed piston 22. That is, the inclination angle of the swash plate 15 which affects the compression capacity changes. The pressure in the crank chamber 2a is controlled by a capacity control valve 24 attached to the rear housing 3.

The suction chamber 3a is connected to the receiving hole 13 through the opening 4c.
Is in communication with When the blocking body 21 is located at the closed position, the opening 4 c is blocked from the suction passage 54. The suction passage 54 is an inlet for introducing refrigerant gas into the compressor, and the position where the blocking body 21 blocks on the passage from the suction passage 54 to the suction chamber 3 a is on the downstream side of the suction passage 54.

A passage 59 is formed in the rotating shaft 9. The inlet 59a of the passage 59 opens into the crank chamber 2a near the lip seal 12, and the outlet 59b of the passage 59
Is opened in a sliding contact area between the inner peripheral surface of the blocking body 21 and the rotating shaft 9. The opening of the passage 59 on the end face of the rotating shaft 9 is closed by the ball 41. As shown in FIG. 4, an annular passage 60 is formed on the inner peripheral surface of the blocking body 21.
The exit 5 of the passage 59 within the slidable range of the blocking body 21
9b is always in communication with the passage 60.

An annular seal ridge 21d is formed on the inner peripheral surface of the blocking body 21. The seal ridge 21d is the rotating shaft 9
The passage 60 is sealed from the hollow portion on the small-diameter portion 21b side.

In the vicinity of the step portion 21c of the blocking member 21, the through hole 6
1 extends from the inner peripheral surface to the outer peripheral surface of the blocking body 21. The passage 61 communicates the passage 60 with the housing hole 13. The accommodation hole 13 and the communication port 4c communicate with each other through the throttle passage 62. The outlet of the throttle passage 62 is set on the downstream side of the position (that is, the positioning surface 55) where the blocking body 21 blocks on the passage from the suction passage 54 to the suction chamber 3a.
That is, the crank chamber 2a communicates with the suction chamber 3a via the pressure release passage 63 including the passages 59 and 60, the communication port 61, the housing hole 13, and the throttle passage 62, and the refrigerant gas in the crank chamber 2a is released from the pressure release passage. It flows out to the suction chamber 3a via 63. The passage cross-sectional area of the throttle passage 62 constituting the pressure release passage 63 is smaller than the passage cross-sectional areas of the passages 59, 60 and the passage 61, and the refrigerant gas flowing from the crank chamber 2 a to the suction chamber 3 a is throttled by the throttle passage 62. Be affected.

The internal structure of the displacement control valve 24 will be described with reference to FIGS. Bobbin 2 supporting solenoid 25
A guide cylinder 27 is fixed to the hollow portion of the tube 6, and a fixed iron core 28 is accommodated and fixed in the guide cylinder 27. A movable iron core 29 is accommodated in the guide cylinder 27 so as to be able to approach and separate from the fixed iron core 28. Fixed iron core 28 and movable iron core 29
A valve opening forcing spring 30 is interposed between the two. The movable iron core 29 is urged in a direction away from the fixed iron core 28 by the spring action of the valve opening forcing spring 30.

A valve housing 31 is fixedly connected to the bobbin 26 via a connecting member 32, and a spherical valve body 33 is accommodated in the valve housing 31. The valve housing 31 is provided with a discharge pressure introduction port 31a, a suction pressure introduction port 31b, and a control port 31c. The discharge pressure introduction port 31a communicates with the discharge chamber 3b via a discharge pressure introduction passage. Suction pressure introduction port 31
b communicates with the suction passage 54 via the suction pressure introduction passage 35, and the control port 31c communicates with the crank chamber 2a via the control passage 37. The exit of the control passage 37 is directed to the vicinity of the periphery of the swash plate 15.

A return spring 39 and a valve support seat 40 are interposed between the spring receiver 38 in the valve housing 31 and the valve body 33, and the valve body 33 moves the return spring 39 in a direction to close the valve hole 31d. Subject to spring action.

A bellows fitting 44 is accommodated in the suction pressure detection chamber 43 communicating with the suction pressure introduction port 31b in a state of being fixed to the movable iron core 29. The bellows fitting 44 and the spring receiver 45 are connected by a bellows 46, and a spring 47 is interposed between the bellows fitting 44 and the spring receiver 45. A transmission rod 48 is fixed to the spring receiver 45, and the tip of the transmission rod 48 contacts the valve body 33.

The valve housing 31 and its internal members constitute a capacity control valve 24a, and the valve body 33 opens and closes a valve hole 31d according to a change in suction pressure in the suction pressure detection chamber 43.
When the valve hole 31d is closed, the communication between the discharge pressure introducing port 31a and the control port 31c is cut off.

A suction passage 54 for introducing the refrigerant gas into the suction chamber 3a and an outlet 1 for discharging the refrigerant gas from the discharge chamber 3b.
c is connected by an external refrigerant circuit 49. On the external refrigerant circuit 49, a condenser 50, an expansion valve 51, and an evaporator 52 are interposed. The expansion valve 51 controls the flow rate of the refrigerant according to the change in the gas pressure on the outlet side of the evaporator 52.

The solenoid 25 is controlled by the control computer C to excite and demagnetize. The control computer C turns on the air conditioner operation switch 57 or turns on the accelerator switch 58
The solenoid 25 is excited by the FF, and the air conditioner operation switch 57 is turned off or the accelerator switch 58 is turned off.
N demagnetizes the solenoid 25. In the state shown in FIG. 1, the solenoid 25 is in an excited state. In the excited state of the solenoid 25, the movable iron core 29 is attracted to the fixed iron core 28 against the spring action of the valve opening forcing spring 30, as shown in FIG.

When the solenoid 25 is excited, the bellows 46 is displaced in accordance with a change in suction pressure introduced from the suction passage 54 through the suction pressure introduction passage 35, and this displacement is transmitted through the transmission rod 48 to the valve. It is transmitted to the body 33. When the suction pressure is high (the cooling load is high), the valve opening of the valve body 33 decreases. The refrigerant gas in the crank chamber 2a flows out to the suction chamber 3a via the pressure release passage 63. Therefore, when the valve opening degree of the valve body 33 becomes small, the discharge chamber 3b passes through the pressure supply passage 34, the discharge pressure introduction port 31a, the valve hole 31d, the control port 31c and the control passage 37 through the pressure supply passages of the crank chamber. The amount of refrigerant gas flowing into 2a is reduced. Therefore, the pressure in the crank chamber 2a decreases.
Further, since the suction pressure in the cylinder bore 1a is also high, the difference between the pressure in the crank chamber 2a and the suction pressure in the cylinder bore 1a becomes small. Therefore, as shown in FIG. 1 and FIG. 6, the swash plate inclination angle increases.

Conversely, suction pressure is low (cooling load is small)
In this case, the valve opening of the valve body 33 increases, and the amount of refrigerant gas flowing from the discharge chamber 3b into the crank chamber 2a increases. Therefore, the pressure in the crank chamber 2a increases. Further, since the suction pressure in the cylinder bore 1a is low, the difference between the pressure in the crank chamber 2a and the suction pressure in the cylinder bore 1a increases. Therefore, the inclination angle of the swash plate is reduced.

When the suction pressure becomes very low (no cooling load), the valve element 33 approaches the maximum opening position as shown in FIG. When the air conditioner operation switch 57 is turned off or the accelerator switch 58 is turned on, the solenoid 25 is turned on.
Is demagnetized, the movable iron core 29 is separated from the fixed iron core 28 by the spring action of the valve opening forcing spring 30, as shown in FIG. 8, and the valve body 33 moves to the maximum opening position. In a maximum opening state as shown in FIG. 8 or a state close to the maximum opening as shown in FIG. 7, the refrigerant gas in the discharge chamber 3b rapidly flows into the crank chamber 2a. Therefore, the pressure in the crank chamber 2a is rapidly increased, and the pressure in the crank chamber 2a reaches a maximum pressure state, and the inclination of the swash plate 15 shifts to the minimum inclination.

As the tilt angle of the swash plate 15 shifts to the minimum tilt side, the swash plate support 14 moves toward the blocking body 21 and comes into contact with the transmission cylinder 56. Swash plate support 1 that moves to blocking body 21 side
4 presses the transmission cylinder 56 against the inner ring 53b of the deep groove ball bearing member 53. Since the transmission cylinder 56 is sandwiched between the swash plate support 14 and the inner ring 53b, the transmission cylinder 56 rotates together with the rotating shaft 9. The transmission cylinder 56 is a deep groove ball bearing member 5
3, the rotating shaft 9, the swash plate support 14, the transmission cylinder 56, and the inner ring 53b rotate integrally, and the swash plate support 14, the transmission cylinder 56, and the inner ring 53
No sliding contact occurs between b.

When the swash plate support 14 further moves toward the blocking member 21 in a state where the transmission cylinder 56 is pressed against the deep groove ball bearing member 53, the blocking member 21 is pushed toward the positioning surface 55, and the blocking member 21 is pressed. The tip of the small-diameter portion 21b of 21 is a positioning surface 55
Approaching. By this approach operation, the cross-sectional area of the refrigerant gas passage from the suction passage 54 to the suction chamber 3a is gradually reduced. This throttling action causes the suction passage 54 to move from the suction chamber 3a.
Gradually reduce the amount of refrigerant gas flowing into the system. for that reason,
The amount of refrigerant gas drawn into the cylinder bore 1a from the suction chamber 3a also gradually decreases, and the discharge capacity gradually decreases. As a result, the discharge pressure gradually decreases, and the torque in the compressor does not fluctuate greatly in a short time.

When the distal end of the small diameter portion 21b of the blocking member 21 comes into contact with the positioning surface 55, the external refrigerant circuit 49 causes the suction chamber 3 to move.
The flow of the refrigerant gas into a stops. Since the minimum inclination angle of the swash plate is not 0 °, the discharge from the discharge cylinder bore 1a to the discharge chamber 3b is performed even when the inclination angle of the swash plate is minimum.
Therefore, when the flow of the refrigerant gas from the external refrigerant circuit 49 to the suction chamber 3a is stopped, the refrigerant gas discharged from the cylinder bore 1a to the discharge chamber 3b is discharged from the discharge pressure introducing passage 34, the passage in the control valve 24, and the control passage. It flows into the crank chamber 2a through a pressure supply passage 37. The refrigerant gas in the crank chamber 2a flows into the suction chamber 3a through the pressure release passage 63, and the refrigerant gas in the suction chamber 3a is sucked into the cylinder bore 1a and discharged to the discharge chamber 3b. That is, when the inclination angle of the swash plate is minimum, the circulation passages of the discharge chamber 3b, the discharge pressure introduction passage 34, the passage in the control valve 24, the control passage 37, the crank chamber 2a, the pressure release passage 63, the suction chamber 3a, and the cylinder bore 1a are formed. Made in the compressor. The refrigerant gas in the compressor circulates through the circulation passage, and a pressure difference is generated between the discharge chamber 3b, the crank chamber 2a, and the suction chamber 3a. Further, the refrigerant gas in the compressor does not flow out to the external refrigerant circuit 49, and there is no possibility that frost is generated in the evaporator 52.

When the cooling load increases from the state shown in FIG. 7 and the suction pressure rises, this rise in the suction pressure spreads from the suction passage 54 to the suction pressure detection chamber 43. Therefore, the bellows 46 contracts and the valve body 33 closes the valve hole 31d. Alternatively, when the air conditioner operation switch 57 or the accelerator switch 58 is turned on from the state of FIG. 8, the solenoid 25 is excited, and the movable iron core 29 is sucked into the fixed iron core 28. Therefore, the bellows 46 moves from the suction passage 54 to the suction pressure detecting chamber 4.
The valve body 33 is reduced and displaced by the suction pressure spreading to the valve body 33.
Closes the valve hole 31d.

The discharge chamber 3b, the crank chamber 2a and the suction chamber 3
There is a pressure difference between a. Therefore, the valve body 33 is
When 1d is closed, the pressure in the crank chamber 2a decreases,
The swash plate inclination increases from the minimum inclination. The swash plate support 14 moves in the direction away from the blocking body 21 due to the increase in the tilt angle. However, the blocking body 21 follows the movement of the swash plate support 14 by the spring force of the suction passage opening spring 36, and the small diameter portion 21b The tip is separated from the positioning surface 55. By this separating operation, the cross-sectional area of refrigerant gas passage from the suction passage 54 to the suction chamber 3a gradually increases. The gradually increasing cross-sectional area of the passage gradually increases the amount of refrigerant gas flowing from the suction passage 54 into the suction chamber 3a. Therefore, the amount of refrigerant gas sucked into the cylinder bore 1a from the suction chamber 3a also gradually increases, and the discharge capacity gradually increases. As a result, the discharge pressure gradually increases, and the torque in the compressor does not greatly change in a short time.

In order to properly control the inclination angle of the swash plate 15, it is necessary to properly adjust the pressure in the crank chamber 2a. For this purpose, the flow rate of the refrigerant gas discharged from the pressure release passage 63 to the suction chamber 3a must be controlled. It must be done with high accuracy. This flow rate is controlled by the throttle passage 62 which is a part of the pressure release passage 63. However, if gas leaks in the middle of the pressure release passage 63, the swash plate tilt angle cannot be properly controlled. Gas leakage in the middle of the pressure release passage 63 is likely to occur between the peripheral surface of the rotating shaft 9 and the seal ridge 21d. In order to eliminate the gas leakage, it is necessary to join the peripheral surface of the rotating shaft 9 and the sealing ridge 21d as much as possible.
The friction between the peripheral surface of the seal member and the seal ridge 21d is increased. In the clutchless compressor, the rotating shaft 9 keeps rotating unless the external drive source is stopped. Therefore, high friction between the peripheral surface of the rotating shaft 9 and the seal ridge 21d causes wear or seizure. If seizure occurs between the peripheral surface of the rotating shaft 9 and the seal ridge 21d, the blocking body 21 cannot slide and the swash plate tilt angle control cannot be performed. If abrasion occurs between the peripheral surface of the rotating shaft 9 and the seal ridge 21d, the leakage of the refrigerant gas from the middle of the pressure release passage 63 increases, making it impossible to properly control the inclination of the swash plate.

In this embodiment, when the shutoff 21 is in the open position, the refrigerant gas in the crank chamber 2a flows to the suction chamber 3a via the pressure release passage 63. When the shut-off body 21 is in the closed position, the refrigerant gas in the discharge chamber 3b flows through the pressure supply passage including the discharge pressure introduction passage 34 and the control passage 37, the crank chamber 2a,
The fluid flows back to the discharge chamber 3b through the pressure release passage 63, the suction chamber 3a, and the cylinder bore 1a. Passage 6 which is a part of pressure release passage 63
Reference numeral 0 denotes a sliding contact area between the rotating shaft 9 and the blocking body 21, and the sliding contact area is lubricated by the lubricating oil that moves together with the refrigerant gas. Therefore, the peripheral surface of the rotating shaft 9 and the seal ridge 21d
Abrasion or seizure is prevented. Further, the lubricating oil enters between the peripheral surface of the rotating shaft 9 and the seal ridge 21d. Therefore, the sealing performance between the peripheral surface of the rotating shaft 9 and the seal ridge 21d is enhanced, and the peripheral surface of the rotating shaft 9 and the seal ridge 21d
d can be reliably prevented from leaking. Further, good lubrication of the sliding contact area between the rotating shaft 9 and the blocking body 21 contributes to smooth sliding of the blocking body 21, and the sliding of the blocking body 21 smoothly narrows and enlarges the cross-sectional area of passage.

In the present embodiment, the receiving hole 13 is
3, and a sliding contact area between the blocker 21 and the cylinder block 1 is lubricated by lubricating oil that moves together with the refrigerant gas. Therefore, the sliding smoothness of the blocking body 21 is further improved.

Since the inlet 59 a of the pressure release passage 63 is near the lip seal 12, the lubricating oil that moves with the refrigerant gas flowing into the pressure release passage 63 enhances the sealing property of the lip seal 12. Further, since the outlet of the control passage 37 is directed to the vicinity of the peripheral edge of the swash plate 15, the refrigerant gas flow flowing from the control passage 37 into the crank chamber 2a is blown to the sliding contact portion of the swash plate 15 with the shoe 23. Lubrication of the sliding contact portion is performed.

The present invention is, of course, not limited to the above embodiment, but may be, for example, the embodiment shown in FIG.
In this embodiment, instead of omitting the pressure release passage in the rotating shaft 9, the passage 60 on the inner peripheral surface of the blocking body 21 is replaced with the deep groove ball bearing member 5.
No. 3 communicates with the gap between the outer ring 53a and the inner ring 53b. Refrigerant gas in the crank chamber 2a includes an outer ring 53a and an inner ring 5
3b, and flows into the passage 60 via the gap. Accordingly, the sliding contact area between the rotating shaft 9 and the blocking body 21 is sufficiently lubricated as in the above-described embodiment, and the lubrication of the deep groove ball bearing member 53 is more favorably lubricated than in the above-described embodiment.

[0049]

As described above in detail, the present invention can switch between a closed position for closing a suction passage for introducing refrigerant gas from an external refrigerant circuit to the suction chamber and an open position for opening the suction passage. The swash plate is slidably and relatively rotatably supported on the rotating shaft, and the slide of the swash plate is interlocked with at least a part of the inclination angle of the swash plate, and the inclination angle of the swash plate when the shutter is in the closed position. the so was set to be minimum inclination angle, an excellent effect of being able to suppress the torque variation by preventing a rapid variation of the discharge pressure. Further, a part of the pressure release passage is formed in a sliding contact area between the blocker and the rotating shaft, and an outlet of the pressure release passage is set downstream from a blocking position on the suction passage blocked by the blocker. Therefore, there is an excellent effect that the sliding contact area is always lubricated and the flow of the refrigerant gas is reduced, or the smooth operation of the increasing blocking body is secured.

[Brief description of the drawings]

FIG. 1 is a side sectional view of an entire compressor according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is a sectional view taken along line CC of FIG. 1;

FIG. 5 is a side sectional view of the entire compressor in a state where a swash plate tilt angle is at a minimum.

FIG. 6 is an enlarged sectional view of a main part in which a blocking body is in an open position.

FIG. 7 is an enlarged sectional view of a main part in which a blocking body is in a closed position.

FIG. 8 is an enlarged cross-sectional view of a main part in which a breaker is in a closed position and a solenoid is in a demagnetized state.

FIG. 9 is an enlarged sectional view of a main part showing another example.

[Explanation of symbols]

2a: crank chamber, 3a: suction chamber, 3b: discharge chamber, 9 ...
Rotating shaft, 14 swash plate support, 15 swash plate, 21 interrupter, 22 single-ended piston, 24a capacity control valve, 49
External refrigerant circuit, 55: Positioning surface at a position interrupted by the interrupter, 63: Pressure release passage.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tomohiko Yokono 2-1-1, Toyota-cho, Kariya-shi, Aichi Pref. Inside Toyota Industries Corporation (58) Field surveyed (Int. Cl. ⁷ , DB name) F04B 27 / 08 F04B 27/14

Claims (2)

(57) [Claims] 1. A crank chamber, a suction chamber, a discharge chamber, and each of these
The cylinder bores to connect the chamber to partition formed, a single-headed piston rotatably supports the rotary shaft to reciprocating linear motion can accommodate to the housing into the cylinder bore, the rotational support to the rotating shaft
At the same time , the swash plate is tiltably linked to the rotating support, and the inclination angle of the swash plate is controlled by the difference between the pressure in the crank chamber and the suction pressure through a single-headed piston. The pressure in the discharge pressure region is supplied to the crank chamber via a pressure supply passage connecting the crank chamber and the pressure supply is controlled by a capacity control valve, and the pressure in the discharge pressure region is connected between the crank chamber and the suction pressure region. In a clutchless one-sided piston-type variable displacement compressor that releases pressure of a crank chamber to a suction pressure region through a pressure passage to regulate the pressure in the crank chamber, a refrigerant gas is introduced from an external refrigerant circuit into the suction chamber. A blocking member is slidably and relatively rotatably supported on the rotating shaft so as to be switchable between a closed position for closing the suction passage and an open position for opening the suction passage, so that the inclination angle of the swash plate is reduced . And a part of the sly Is interlocked, and the inclination of the swash plate when the blocking member is in the closed position and the minimum inclination angle
And the release forms part of the pressure passage into sliding contact area between the rotary shaft and the blocking member, the outlet of the pressure passage releasing the downstream of the shut-off position on the suction passage which is blocked by the blocking member Set clutchless one-sided piston type variable displacement compressor. 2. The pressure release passage is formed in a rotary shaft, and an inlet of the pressure release passage opens into the crank chamber near a lip seal for sealing a peripheral surface of the rotary shaft. Clutchless one-sided piston type variable displacement compressor.