JP3267426B2 - 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 one-side piston type variable displacement swinging swash plate type compressor disclosed in Japanese Patent Application Laid-Open No. 3-37378, connection and disconnection of power transmission between an external drive source and a rotary shaft of the compressor are controlled. Not use electromagnetic clutch. If the electromagnetic clutch is eliminated, especially in the on-vehicle form, its ON-OF
It is possible to eliminate the drawback of poor feeling due to the shock of F and to reduce the weight and cost of the entire compressor.

Since the difference between the maximum value and the minimum value of the load torque is large in the one-sided piston type variable displacement compressor, engine stall in a vehicle equipped with the one-sided piston type variable displacement compressor becomes a problem. The cause of the engine stall is the load on the power steering mechanism. Therefore, an idle-speed controller is used. The idle-speed controller supplementarily adjusts the air supply amount to the engine based on the load detection information of the power steering mechanism.

[0004]

In a vehicle equipped with a clutchless one-side piston type variable displacement compressor, the load fluctuation of the compressor has a great effect on engine stall. For example, when a sudden brake is applied while the vehicle is running, the rotational speed of the vehicle engine sharply decreases, and the driving force of the vehicle engine sharply decreases. In such a state, if the displacement of the variable displacement compressor is large, that is, if the load is large, the vehicle engine stops. Therefore, it is necessary to detect the displacement of the variable displacement compressor that reflects the load torque of the variable displacement compressor and control the air supply amount adjustment of the idle-speed controller. To detect the displacement of a one-sided piston type variable displacement compressor, it is necessary to detect the inclination of the swash plate. However, this inclination is difficult to detect, and accurate detection of the displacement cannot be expected.

An object of the present invention is to prevent a large load torque from being applied to a vehicle engine in a small driving force state without depending on the detection of the displacement of a clutchless one-side piston type variable displacement compressor.

[0006]

According to the present invention, there is provided:
A swash plate support is slidably supported on a rotary shaft in a housing which defines a crank chamber, a suction chamber, a discharge chamber, and a cylinder bore connecting these chambers, and accommodates a single-headed piston in the cylinder bore so as to reciprocate linearly. The swash plate is tiltably supported on the swash plate support, and the swash plate is tiltably linked to the rotating support fixed to the rotating shaft, so that a single-headed piston of the pressure in the crank chamber and the suction pressure. The inclination of the swash plate is controlled by the difference through the pressure supply, the pressure in the discharge pressure area is supplied to the crank chamber through the pressure supply passage connecting the discharge pressure area and the crank chamber, and this pressure supply is responsive to the suction pressure. A clutchless one-sided piston type variable valve that controls the pressure in the crank chamber by releasing the pressure in the crank chamber to the suction pressure area through a pressure release passage that connects the crank chamber and the suction pressure area. In the present invention, the first pressure chamber for introducing the refrigerant gas in the discharge pressure region and the second pressure for introducing the refrigerant gas in the discharge pressure region through a throttle passage are provided. A chamber for partitioning the first pressure chamber and the second pressure chamber to oppose the pressures of the two pressure chambers;
A swash plate tilt angle changing passage connecting the discharge pressure region and the crank chamber, and the swash plate tilt angle based on a displacement of a partition body that is displaced based on a differential pressure between the first pressure chamber and the second pressure chamber. The swash plate inclination changing means is provided with an opening change valve for changing the opening of the change passage.

According to the second aspect of the present invention, the first pressure chamber for introducing the refrigerant gas in the crank chamber, the second pressure chamber for introducing the refrigerant gas in the crank chamber through a throttle passage, and the first pressure chamber. A partition for partitioning the pressure chamber and the second pressure chamber to oppose the pressures of the two pressure chambers, a swash plate inclination changing passage connecting the discharge pressure region and the crank chamber, and the first pressure chamber. A swash plate inclination changing force changing means for changing the opening of the swash plate inclination changing passage based on the displacement of the partition body displaced based on the pressure difference between the swash plate and the second pressure chamber. Configured.

According to the third aspect of the invention, the valve body of the displacement control valve is the opening degree changing valve body, and the pressure supply passage is the swash plate inclination angle changing passage.

[0009]

According to the first aspect of the present invention, when the pressure in the discharge pressure region does not fluctuate rapidly, the refrigerant gas pressure in the first pressure chamber and the refrigerant gas pressure in the second pressure chamber are balanced. ing. When the swash plate inclination changing passage bypasses the pressure supply passage, the opening degree changing valve body closes the swash plate inclination changing passage in the pressure equilibrium state. When the pressure in the discharge pressure region drops rapidly, the refrigerant gas pressure in the first pressure chamber also drops immediately, but the refrigerant gas pressure in the second pressure chamber does not drop abruptly due to the throttle action of the throttle passage. Therefore, the refrigerant gas pressure in the second pressure chamber becomes higher than the refrigerant gas pressure in the first pressure chamber, and the partition body is displaced toward the first pressure chamber. This displacement causes the opening degree changing valve body to open the swash plate inclination angle changing passage, and the refrigerant gas in the discharge pressure region flows into the crank chamber through the swash plate inclination angle changing passage. Therefore, the pressure in the crank chamber rises sharply, and the swash plate inclination quickly shifts to the minimum inclination. That is, when the vehicle is suddenly braked, the discharge pressure of the mounted compressor rapidly decreases, and the load torque of the compressor immediately decreases. Accordingly, a large load torque of the compressor does not affect the vehicle engine in the small driving force state due to the sudden braking, and the problem of engine stall is avoided.

According to the second aspect of the invention, when the pressure in the suction pressure region does not fluctuate rapidly, the refrigerant gas pressure in the first pressure chamber and the refrigerant gas pressure in the second pressure chamber are balanced. ing. When the swash plate inclination changing passage bypasses the pressure supply passage, the opening degree changing valve body closes the swash plate inclination changing passage in the pressure equilibrium state. When the rotational speed of the vehicle engine suddenly decreases, the suction pressure decreases. Due to this decrease in suction pressure, the capacity control valve increases the opening of the pressure supply passage, and the pressure in the crank chamber rises. This pressure increase causes a rapid pressure increase in the first pressure chamber, but does not cause a rapid pressure increase in the second pressure chamber due to the throttle action of the throttle passage. Therefore, the refrigerant gas pressure in the second pressure chamber becomes lower than the refrigerant gas pressure in the first pressure chamber, and the partition body is displaced toward the second pressure chamber. This displacement causes the opening degree changing valve body to open the swash plate inclination angle changing passage, and the refrigerant gas in the discharge pressure region flows into the crank chamber through the swash plate inclination angle changing passage. Therefore, the pressure in the crank chamber rises sharply, and the swash plate inclination quickly shifts to the minimum inclination.

According to the third aspect of the invention, the valve body of the displacement control valve shifts in the opening increasing direction due to the pressure difference between the two pressure chambers due to the rapid decrease in the rotation speed of the vehicle engine. Therefore, the refrigerant gas in the discharge pressure region flows into the crank chamber, and the swash plate inclination quickly shifts to the minimum inclination.

[0012]

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, 4 and 5, a cylindrical blocking body 2 is provided in a housing hole 13 at the center of the cylinder block 1.
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 21 a 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. The spring 42 functions 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. 4, 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. .

A transmission cylinder 56 is interposed between the swash plate support 14 and the deep groove ball bearing member 53 so as to be slidable on the rotating shaft 9. 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.

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 accommodation 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. An annular passage 60 is formed on the inner peripheral surface of the blocking body 21, and the outlet 59 b of the passage 59 is always in communication with the passage 60 within the slidable range of the blocking body 21.

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 body 21, there is a 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 a passage 62. The crank chamber 2a includes passages 59 and 60, a passage 61,
The refrigerant gas communicates with the suction chamber 3a through the pressure release passage 63 including the housing hole 13 and the passage 62, and the refrigerant gas flowing from the crank chamber 2a to the suction chamber 3a is subjected to the throttle action in the passage 62.

As shown in FIG. 1, FIG. 4 and FIG.
In b, a bypass opening / closing valve 6 serving as a swash plate inclination changing means is provided.
4 are provided. As shown in FIG. 5, a discharge pressure introduction port 65a and a supply port 65 are provided in the valve housing 65.
b is formed. The discharge pressure introduction port 65a communicates with the discharge chamber 3b, and the supply port 65b is connected to the supply passage 66.
Through the crank chamber 2a. Supply passage 66
Constitutes a swash plate inclination changing passage together with the discharge pressure introducing port 65a, the passage in the valve housing 65 and the supply port 65b. A ball valve 67 serving as an opening degree changing valve body and a valve support seat 68 supporting the ball valve 67 are provided in the valve housing 65.
And a return spring 69 are accommodated. The ball valve 67 is always held at a position where the valve hole 65c is closed by the spring force of the return spring 69.

A piston 71 serving as a partition is accommodated in a piston housing 70 connected to the valve housing 65. The piston 71 is a piston housing 70
Partitioning the inner to the first pressure chamber P ₁ and the second pressure chamber P _2. The first pressure chamber P ₁ is communicated with the discharge pressure introducing port 65a via the through hole 65e. The piston 71 can be slid and displaced in the direction of increasing or decreasing the volume of both pressure chambers P ₁ and P ₂ . There is a clearance K serving as a throttle passage between the peripheral surface of the piston 71 and the inner peripheral surface of the piston housing 70. If there is a pressure difference between the two pressure chambers P ₁ and P ₂ , the refrigerant gas on the high pressure side is cleared. It flows to the pressure chamber on the low pressure side while being subjected to the throttle action at K.

The displacement of the piston 71 toward the _first pressure chamber P1 is restricted by the contact with the end face 65d of the valve housing 65, and the displacement of the piston 71 toward the _second pressure chamber P2 is caused by the step 70a. Is regulated by the contact. The piston 71 is always held at a position where it comes into contact with the step 70a by the spring force of the return spring 72.

A displacement transmission rod 73 is slidably penetrated through the valve housing 65, and one end thereof protrudes from an end face 65d of the valve housing 65. The other end of the displacement transmission rod 73 is in contact with the ball valve 67.
When the piston 71 is in contact with the end face 65d, the ball valve 67 opens the valve hole 65c, and the discharge chamber 3b and the crank chamber 2a
Communicate with each other through a swash plate inclination angle changing passage including a discharge pressure introducing port 65a, a passage in the valve housing 65, a supply port 65b, and a supply passage 66.

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.

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 element 33, and the valve element 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 body 33 is provided with a valve hole 31 d according to a change in suction pressure in the suction pressure detection chamber 43.
Open and close. 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 a 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 34, 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. If the valve opening of the valve body 33 becomes small, the discharge pressure introduction passage 3
4. The amount of refrigerant gas flowing into the crank chamber 2a via the pressure supply passage including the discharge pressure introduction port 31a, the valve hole 31d, and the control passage 37 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, the swash plate tilt angle increases as shown in FIG.

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 inclination angle of the swash plate 15 shifts to the minimum inclination side, the blocking body 21 is pushed toward the positioning surface 55,
The tip of the small diameter portion 21 b of the blocking body 21 approaches the positioning surface 55. 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. Therefore, the amount of refrigerant gas sucked 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. That is, the main object of the clutchless compressor is to avoid impact.

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, a pressure difference is generated between the discharge chamber 3b, the crank chamber 2a, and the suction chamber 3a even when the swash plate tilt angle is in the minimum state.
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 blocker 21 follows the movement of the swash plate support 14 by the spring force of the suction passage opening spring 36, and the cross-sectional area of the refrigerant gas passage from the suction passage 54 to the suction chamber 3a gradually increases. 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.

The discharge pressure of the discharge chamber 3b is controlled by the discharge pressure introducing port 6.
5a and the first of the bypass on-off valve 64 through the port 65e.
It is introduced into the pressure chamber P ₁ of. The first pressure chamber P ₁ and the second pressure chamber P ₂ communicate with each other via a clearance K between the inner peripheral surface of the piston housing 70 and the piston 71. Accordingly, a first refrigerant gas pressure in the pressure chamber P ₁ of the second refrigerant gas pressure in the pressure chamber P ₂ is balanced when the pressure in the discharge chamber 3b is in a state which does not rapidly change. In this pressure equilibrium state, the ball valve 67 is connected to the discharge chamber 3b and the crank chamber 2a.
The refrigerant gas in the discharge chamber 3b does not flow into the crank chamber 2a via the supply passage 66.

When the vehicle is suddenly braked, the engine speed drops rapidly, and the compressor speed also drops rapidly. When the rotational speed of the compressor suddenly decreases, the discharge pressure sharply decreases. Refrigerant gas pressure in the pressure chamber P ₁ pressure when rapidly reduced first discharge chamber 3b also immediately sudden drop, the second refrigerant gas pressure in the pressure chamber P ₂ is higher than the first refrigerant gas pressure in the pressure chamber P ₁ Will also be higher. Therefore, a second refrigerant gas in the pressure chamber P ₂ flows into the first pressure chamber P ₁ via the clearance K. But,
Second refrigerant gas pressure in the pressure chamber P ₂ is not reduced sharply because of the throttling effect of the clearance K. Therefore, the second pressure chamber P
The pressure difference between the _second refrigerant gas pressure in the first pressure chamber refrigerant gas pressure P ₁ moves the piston 71 to the first pressure chamber P ₁ side.

As shown in FIG. 6, the piston 71 is
It is displaced to a position where it comes into contact with d. This displacement is transmitted to the ball valve 67 via the displacement transmission rod 73, and the ball valve 6
7 opens the valve hole 65c. As a result, the discharge chamber 3b communicates with the crank chamber 2a via the supply passage 66, and the discharge chamber 3b
Refrigerant gas flows into the crank chamber 2a through the supply passage 66. Therefore, the pressure in the crank chamber 2a sharply rises, and the swash plate 15 not at the minimum inclination quickly shifts to the minimum inclination state. That is, when the vehicle is suddenly braked, the discharge pressure of the mounted compressor rapidly decreases, and the load torque of the compressor immediately decreases. Accordingly, a large load torque of the compressor does not affect the vehicle engine in the small driving force state due to the sudden braking, and the problem of engine stall is avoided.

After the piston 71 contacts the end face 65d,
Second pressure in the pressure chamber P ₂ is Yuki approaches slowly the first pressure in the pressure chamber P _1, the piston 71 returns to the position abutting on the step 70a by the spring force of the return spring 72.
Therefore, the ball valve 67 closes the valve hole 65c, and the supply passage 6
The communication between the discharge chamber 3b and the crank chamber 2a via 6 is cut off. Therefore, the swash plate 15 returns to the tilt position before the sudden braking is applied.

The piston 71 of the bypass on-off valve 64
A through-hole may be provided through the end face of the diaper so that the cross-sectional area of the through-hole can be adjusted by adjusting the screwing of the needle screw. The responsiveness of the piston displacement using the throttle action in the clearance between the inner peripheral surface of the piston housing 70 and the peripheral surface of the piston 71 tends to vary due to manufacturing errors of the piston 71 and the piston housing 70.
Adjusting the throttle of the needle screw can eliminate variations in the response of piston displacement.

The present invention is also applicable to the embodiments shown in FIGS. In this embodiment, a bypass opening / closing valve 74 serving as a swash plate forcible angle changing means accommodated in the discharge chamber 3b communicates the discharge chamber 3b with the crank chamber 2a in response to a sudden pressure drop in the crank chamber 2a. . The discharge pressure introduction port 75a on the valve housing 75 communicates with the discharge chamber 3b, and the supply port 75b communicates with the crank chamber 2a via the supply passage 66. The piston housing 76 is divided into a first pressure chamber P ₃ and a second
Of which is divided into a pressure chamber P _4, the first pressure chamber P ₃ is communicated with the supply port 75b via the through hole 75c.

[0050] The piston 77 is biased by the spring force of the return spring 78 to the first pressure chamber P ₃ side, a return spring 7
The spring force of No. 8 is transmitted to a ball valve 80 serving as an opening degree change piece via a piston 77 and a displacement transmission rod 79. The displacement range of the piston 77 is restricted between a position where the ball valve 80 closes the valve hole 75d and a position where the ball valve 80 contacts the step 76a. A slight clearance K serving as a throttle passage is provided between the inner peripheral surface of the piston housing 76 and the peripheral surface of the piston 77.

The pressure in the crank chamber 2a is supplied to the supply port 75b.
And it is introduced into the first pressure chamber P ₃ of the bypass opening and closing valve 74 through a passage port 75c. And the refrigerant gas pressure of the first refrigerant gas pressure in the pressure chamber P ₃ of the second pressure chamber P ₄ is balanced when the pressure in the crank chamber 2a is in a state of not abruptly change. In this pressure equilibrium state, as shown in FIG. 9, the ball valve 80 blocks the communication between the discharge chamber 3b and the crank chamber 2a, and the refrigerant gas in the discharge chamber 3b flows into the crank chamber 2a via the supply passage 66. Never.

When the vehicle is suddenly braked, the compressor rotates.
The number drops sharply and the suction pressure rises. Therefore, capacity system
The valve opening of the control valve 24 increases, and the pressure in the crank chamber 2a increases.
Increase. When the pressure in the crank chamber 2a increases, the first pressure
Room P_ThreeThe refrigerant gas pressure of the first pressure chamber P immediately increases._Three
Refrigerant gas pressure of the second pressure chamber P_FourHigher than the refrigerant gas pressure
It becomes. Therefore, the first pressure chamber P_ThreeRefrigerant gas
The second pressure chamber P via the alance K_FourFlows to Only
And the second pressure chamber P_FourRefrigerant gas pressure of clearance K
Does not rise sharply due to the throttle action. Therefore, the first pressure
Room P_ThreeRefrigerant gas pressure and the second pressure chamber P_FourRefrigerant gas pressure and
Pressure of the piston 77 in the second pressure chamber P _FourMove to the side,
As shown in FIG. 10, the ball valve 80 opens the valve hole 75d.
As a result, the discharge chamber 3b and the crank chamber 2a
6, and the refrigerant gas in the discharge chamber 3b is supplied to the supply passage 6
6, and flows into the crank chamber 2a. Therefore, clans
The pressure in the work chamber 2a rises sharply, and the swash plate inclination quickly decreases to the minimum inclination.
Move to In other words, a small drive caused by sudden braking
Large load torque of the compressor for a powered vehicle engine
Luke does not spread, the problem of engine stall
Be avoided.

The present invention is not limited to the embodiment shown in FIGS.
Examples are possible. In this embodiment, the swash plate tilt angle compulsory changing means is used.
Opening and closing mechanism 82 is assembled in the capacity control valve 24.
ing. The opening / closing mechanism 82 is fixed inside the valve housing 31.
Fixed piston housing 83 and piston housing
A piston 84 serving as a partition housed in the ring 83,
From the return spring 85 and the valve body 33 that opens and closes the valve hole 31d.
It is configured. The piston inside the piston housing 83
84, the first pressure chamber P_FiveAnd the second pressure chamber P ₆Toni-ku
It is drawn. First pressure chamber P_FiveAnd the second pressure chamber P₆When
Is the inner peripheral surface of the piston housing 83 and the piston 84
They communicate with each other by a clearance K between them and the peripheral surface. First
Pressure chamber P_FiveIs a discharge chamber through a discharge pressure introduction port 31a.
3b.

A hook 84a is formed on the piston 84. The displacement range of the piston 84 is regulated by the contact between the piston 84 and the step 83a on the piston housing 83 and the contact between the hook piece 84a and the wall surface 31e. When the pressures in the two pressure chambers P ₅ and P ₆ are balanced, the hook 84 a of the piston 84 comes into contact with the wall surface 31 e by the spring force of the return spring 85 as shown in FIG. In this contact state, the valve body 33 can close the valve hole 31 d by the spring force of the return spring 39.

[0055] When the discharge pressure sudden braking is multiplied is decreased abruptly, the piston 84 is displaced to the second pressure chamber P ₆ side. Due to this displacement, the hook piece 84a hooks the valve support seat 40, and the valve support seat 40 moves away from the valve hole 31d. As shown in FIG. 12, the valve element 33 released from the spring action of the return spring 39 opens the valve hole 31d widely. Accordingly, the refrigerant gas in the discharge chamber 3b flows through the control passage 37 to the crank chamber 2
a, and the pressure in the crank chamber 2a rises rapidly.
In this embodiment, the control passage 37 is a part of the swash plate inclination angle changing passage. Due to the pressure increase, the swash plate inclination quickly shifts to the minimum inclination. That is, a large load torque of the compressor does not spread to the vehicle engine in the small driving force state due to the sudden braking, and the problem of engine stall is avoided.

[0056]

As described above in detail, according to the present invention, the discharge is performed through the swash plate inclination changing passage due to the rapid generation of a pressure difference between the first pressure chamber and the second pressure chamber of the swash plate inclination changing means. The pressure region and the crankcase communicate with each other, preventing large load torque ripples on the vehicle engine in a small driving force state without depending on the detection of the displacement of the clutchless one-sided piston variable displacement compressor. It has an excellent effect that stalls can be avoided.

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

FIG. 5 is an enlarged sectional view of a main part in which a bypass on-off valve is in a closed state and a swash plate tilt angle is in a maximum state.

FIG. 6 is an enlarged sectional view of a main part in a state where a bypass on-off valve is in an open state.

FIG. 7 is an enlarged sectional view of a main part in which a bypass on-off valve is in a closed state and a swash plate tilt angle is in a minimum state.

FIG. 8 is an enlarged cross-sectional view of a main part in which a bypass on-off valve is in a closed state and a solenoid is in a demagnetized state.

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

FIG. 10 is an enlarged sectional view of a main part with a bypass on-off valve in an open state.

FIG. 11 is an enlarged sectional view of a main part showing another example.

FIG. 12 is an enlarged sectional view of a main part when a sudden brake is applied.

[Explanation of symbols]

2a: crank chamber, 3b: discharge chamber serving as a discharge pressure area, 1
5: swash plate, 64, 74: bypass opening / closing valve serving as swash plate inclination changing means, 66: supply passage forming part of a swash plate inclination changing passage, 67, 80: ball valve serving as an opening change valve body, 7
1,76 ... partition body become piston, P _1, P ₃ ... first pressure chamber, P _2, P ₄ ... second pressure chamber, K ... throttle the passage clearance 82 ... inclination angle of the inclined plate force changing means become closing mechanism, 84 ... partition body become piston, 33 ... opening change valve body and comprising a valve body, 37 ... swash plate inclination angle changing passage and comprising control passage, P ₅ ... first pressure chamber, P ₆ ... first 2 pressure chambers.

Continued on the front page (72) Inventor Takeshi Takeshi 2-1-1 Toyota-cho, Kariya-shi, Aichi Pref. Inside Toyota Industries Corporation (72) Inventor Tomohiko Yokono 2-1-1 Toyota-cho, Kariya-shi, Aichi Pref. Inside the loom mill (72) Inventor Morio Kaneko 535 Sasai, Sayama-shi, Saitama Prefecture Sagimiya Seisakusho Co., Ltd. Field surveyed (Int.Cl. ⁷ , DB name) F04B 27/14 F04B 27/08

Claims (3)

(57) [Claims] 1. A swash plate support on a rotary shaft in a housing which defines a crank chamber, a suction chamber, a discharge chamber, and a cylinder bore connecting these chambers, and accommodates a single-headed piston in the cylinder bore so as to be able to reciprocate linearly. The swash plate is slidably supported, and the swash plate is tiltably supported on the swash plate support, and the swash plate is tiltably linked to a rotating support fixed to a rotating shaft, so that pressure in the crank chamber and suction The inclination of the swash plate is controlled by the difference between the pressure and the pressure through a single-headed piston, and the pressure in the discharge pressure area is supplied to the crank chamber through a pressure supply passage connecting the discharge pressure area and the crank chamber. Is controlled by a displacement control valve that responds to the suction pressure, and the pressure in the crank chamber is released to the suction pressure area through a pressure release passage connecting the crank chamber and the suction pressure area. One side In ton type variable displacement compressor, a first pressure chamber for introducing the refrigerant gas in the discharge pressure region, the introduced refrigerant gas in the discharge pressure region via a throttle passage 2
A pressure chamber, a partition body for partitioning the first pressure chamber and the second pressure chamber to oppose the pressures of the two pressure chambers, and a swash plate tilt angle changing passage connecting the discharge pressure area and the crank chamber. And an opening changing valve body that changes an opening of the swash plate inclination changing passage based on a displacement of the partition body that is displaced based on a differential pressure between the first pressure chamber and the second pressure chamber. And a clutchless one-sided piston type variable displacement compressor having a swash plate inclination changing means. 2. A swash plate support on a rotary shaft in a housing which defines a crank chamber, a suction chamber, a discharge chamber, and a cylinder bore connecting these chambers, and accommodates a single-headed piston in the cylinder bore so as to reciprocate linearly. The swash plate is slidably supported, and the swash plate is tiltably supported on the swash plate support, and the swash plate is tiltably linked to a rotating support fixed to a rotating shaft, so that pressure in the crank chamber and suction The inclination of the swash plate is controlled by the difference between the pressure and the pressure through a single-headed piston, and the pressure in the discharge pressure area is supplied to the crank chamber through a pressure supply passage connecting the discharge pressure area and the crank chamber. Is controlled by a displacement control valve that responds to the suction pressure, and the pressure in the crank chamber is released to the suction pressure area through a pressure release passage connecting the crank chamber and the suction pressure area. One side In ton type variable displacement compressor, a first pressure chamber for introducing the refrigerant gas in the crank chamber, the introduced refrigerant gas in the crank chamber through the throttle passage 2
A pressure chamber, a partition body for partitioning the first pressure chamber and the second pressure chamber to oppose the pressures of the two pressure chambers, and a swash plate tilt angle changing passage connecting the discharge pressure area and the crank chamber. And an opening changing valve body that changes an opening of the swash plate inclination changing passage based on a displacement of the partition body that is displaced based on a differential pressure between the first pressure chamber and the second pressure chamber. And a clutchless one-sided piston type variable displacement compressor having a swash plate inclination changing means. 3. The clutchless one-side piston type according to claim 1, wherein the opening degree changing valve body is a valve body of the displacement control valve, and the swash plate inclination angle changing passage is the pressure supply passage. Variable capacity compressor.