JPH06147117A - Clutchless structure at one side piston type variable capacity compressor - Google Patents

Abstract

PURPOSE:To embody a clutchless compressor which brings compressor non-load. CONSTITUTION:The angle inclination of a swash plate 11 supported swingably on a rotary shaft 6 through a swash plate support body 10 is controlled by adjusting pressure in a crankcase 2a. The pressure in the crankcase 2a is controlled by means of a control valve 22. A spool 8 on the rotary shaft 6 is displaced by the magnetizing demagnetizing changeover of an angle inclination return electromagnetic solenoid 36 is a rear housing 3. The minimum angle inclination of the swash plate 11 is stipulated by butting between the swash plate support body 10 and the spool 8. When the control valve 22 is demagnetized, the pressure in the crankcase 2a rises up suddenly, and the angle inclination of the swash plate 11 becomes small. When the angle inclination return electromagnetic solenoid 36 is demagnetized, the spool 8 retreats into a cylinder block 1, and the angle inclination of the swash plate 11 becomes zero.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention converts the rotary motion of a swash plate tiltably supported by a rotary shaft into a reciprocating linear motion of a single-headed piston, and at the same time, through a single-headed piston of a pressure in a crank chamber and a suction pressure. The present invention relates to a clutchless structure in a one-sided piston type variable displacement compressor that controls the tilt angle of a swash plate by the difference.

[0002]

2. Description of the Related Art In the variable displacement rocking swash plate compressor disclosed in JP-A-59-150988 and JP-A-61-55380, an external drive source and a rotary shaft of the compressor are provided. No electromagnetic clutch is used to connect and disconnect power transmission. If the electromagnetic clutch is eliminated, it is possible to eliminate the drawback of poor feeling in feeling due to the ON / OFF shock, especially in the vehicle-mounted form, and to reduce the weight and cost of the entire compressor.

In each of the variable displacement type swash plate type compressors disclosed in the above-mentioned publications, the pressure in the crank chamber accommodating the swash plate is rapidly increased to bring the swash plate inclination angle to near 0 °, and the discharge capacity is increased. It is designed to drop the to near zero. The load on the compressor sharply decreases due to the sharp decrease in the discharge capacity. When a compressor is installed in a vehicle, it is desirable to direct all of the vehicle engine output to drive the vehicle when accelerating or climbing a vehicle. In such a case, the load on the compressor can be drastically reduced. Be seen.

[0004]

However, in the above-mentioned conventional apparatus, the swash plate inclination angle is not zero when the load on the compressor is rapidly reduced, and the discharge capacity is left to some extent. Therefore, the load of the compressor in the clutch-equipped compressor when the clutch is off is not reached.

An object of the present invention is to provide a clutchless structure capable of achieving a state comparable to no load of the compressor when the clutch is off in the compressor equipped with the clutch.

[0006]

Therefore, according to the present invention,
A crank chamber, a suction chamber, a discharge chamber, and a cylinder bore that connects these chambers are defined and formed, and a swash plate support is slidably supported on a rotary shaft inside a housing that accommodates a single-headed piston in a linearly reciprocating linear motion. Then, the swash plate is tiltably supported on the swash plate support, and the swash plate is tiltably linked to the rotary support on the rotary shaft, and the one-head piston for the pressure in the crank chamber and the suction pressure is used. The present invention is directed to a one-sided piston type variable displacement compressor that controls the tilt angle of the swash plate by the difference. In the first invention, the pressure in the crank chamber is changed based on the external control signal output from the external control signal generator. And a swash plate tilt return means for moving the swash plate support at a position where the swash plate tilt angle is zero on the rotation axis in the direction of increasing the tilt angle of the swash plate. Leading to the discharge pressure area The output pressure introducing port, the suction pressure introducing port communicating with the suction pressure region, the control port communicating with the crank chamber, the valve body that opens and closes the valve hole connecting the discharge pressure introducing port and the control port, and the valve hole is closed. A return spring for urging the valve body in the direction, a pressure sensitive body for urging the valve body in the valve hole opening direction by suction pressure, and a pressure sensitive body for urging the valve body in the valve hole opening direction. The tilt angle compulsory changing means is constituted by the electromagnetic solenoid to be driven.

In the second aspect of the invention, the spool is housed in the cylinder block that houses the single-headed piston and slidably supports the rotary shaft so that the rotary shaft is relatively rotatable, and the spool is separated from the swash plate. The swash plate tilt angle returning means is composed of the elastic means for urging the elastic member in the direction and the electromagnetic solenoid for driving the spool in the direction opposite to the elastic means.

[0008]

The external control signal generator includes the air conditioner switch, the outlet temperature sensor of the evaporator on the external refrigerant circuit, the outside air temperature sensor, the accelerator switch, the lock sensor of the compressor, and the like. When an external control signal is output from such an external control signal generator, the tilt angle compulsory changing means rapidly increases the pressure in the crank chamber. Due to this pressure increase, the swash plate tilt angle shifts to zero,
The compressor becomes unloaded. When the compressor is unloaded, the swash plate support is at a position where the swash plate tilt angle is zero. The swash plate support at the position where the swash plate tilt angle is zero moves in the direction of increasing the swash plate tilt angle when the swash plate tilt angle returning means is operated, and the swash plate tilt angle becomes larger than 0 °. Resuming operation of the compressor starts from this state.

The electromagnetic solenoid forming the tilt angle forced change means is excited by the output of the external control signal from the external control signal generator. Excitation of the electromagnetic solenoid maximizes the valve opening of the valve element, causing the pressure in the crank chamber to rise rapidly. The electromagnetic solenoid is demagnetized during normal compressor operation. In the demagnetized state of the electromagnetic solenoid, the pressure sensitive body fluctuates due to the pressure fluctuation of the suction pressure, and the valve opening of the valve body is controlled. By the valve opening control, the pressure in the crank chamber is controlled according to the fluctuation of the suction pressure, and the tilt angle of the swash plate is controlled.

In the swash plate tilt angle returning means of the second invention, the spool moves by the excitation of the electromagnetic solenoid against the urging action of the elastic means, and the swash plate support at the position where the swash plate tilt angle becomes zero is the spool. The swash plate is pushed in the direction of increasing the tilt angle. This movement causes the swash plate to tilt from zero tilt angle.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment embodying the present invention will now be described with reference to FIGS.
It will be described with reference to FIG. As shown in FIG. 1, a front housing 2 is joined to the front end of a cylinder block 1 which is a part of the housing of the entire compressor. A rear housing 3 is joined and fixed to a rear end of the cylinder block 1 via a valve plate 16, valve forming plates 17A and 17B, and a retainer forming plate 18. An angular bearing 4 is attached inside the front housing 2. A rotary support 5 is supported by the angular bearing 4, and a rotary shaft 6 is fixed to the rotary support 5. The angular bearing 4 receives both the load in the thrust direction and the load in the radial direction acting on the rotary shaft 6 via the rotary support 5.

The front end of the rotary shaft 6 projects from the crank chamber 2a to the outside via the front housing 2, and a pulley 7 is screwed to the projecting end. The pulley 7 is operatively connected to the vehicle engine via a belt 7a. A lip seal 53 is interposed between the front end of the rotary shaft 6 and the front housing 2. The lip seal 53 prevents pressure leakage in the crank chamber 2a.

A spool 8 is fitted and housed in the center of the cylinder block 1 so as to be slidable in the axial direction of the rotary shaft 6. The spool 8 includes a large-diameter cylindrical portion 8a and a small-diameter cylindrical portion 8b, and a rear end portion of the rotating shaft 6 projects into the large-diameter cylindrical portion 8a. The protruding end is rotatably supported by the spool 8 via a radial bearing 9. The radial bearing 9 is slidable with respect to the rotating shaft 6. A return spring 2 is provided between the inner end of the small diameter cylindrical portion 8b and the rear end of the rotary shaft 6.
1 is interposed, and the spool 8 is constantly pressed against the valve plate 16 by the spring action of the return spring 21. When the spool 8 is in contact with the valve plate 16, the end surface of the large-diameter cylindrical portion 8 a coincides with the end surface of the cylinder block 1.

An electromagnetic solenoid 36 for returning the tilt angle is housed in the rear housing 3. The movable iron core 38, which is attracted to the fixed iron core 37 side by the excitation of the tilt return electromagnetic solenoid 36, separates the spool 8 in contact with the valve plate 16 from the valve plate 16. When the spool 8 is separated from the valve plate 16, the end surface of the large-diameter cylindrical portion 8a projects from the end surface of the cylinder block 1 into the crank chamber 2a.

A spherical swash plate support 10 is slidably supported on the rotary shaft 6, and a swash plate 11 is supported on the swash plate support 10 so as to be tiltable in the axial direction of the rotary shaft 6. . Connection pieces 12A and 12B are fixed to the swash plate 11. As shown in FIG. 2, a pair of guide pins 13 and 14 are fixedly attached to the connecting pieces 12A and 12B. Rotating support 5
A support arm 5a is projectingly provided on the. As shown in FIG. 2, a support pin 15 is rotatably supported by the support arm 5a in a direction perpendicular to the rotary shaft 6. The pair of guide pins 13 and 14 are slidably fitted into both ends of the support pin 15. The swash plate 11 can be tilted in the axial direction of the rotary shaft 6 about the swash plate support 10 by the cooperation of the support pin 15 on the support arm 5a and the pair of guide pins 13, 14 and can rotate integrally with the rotary shaft 6. It is possible. The tilt of the swash plate 11 is caused by the support pin 15 and the guide pins 12, 13
It is guided by the slide guide relationship with, the sliding action of the swash plate support 10 and the supporting action of the swash plate support 10.

The maximum tilt angle of the swash plate 11 is restricted by the contact between the tilt angle control projection 5b of the rotary support 5 and the swash plate 11.
Further, the minimum inclination angle of the swash plate 11 is the spool 8 and the swash plate supporter 10.
It is regulated by the contact with. The minimum tilt angle of the swash plate 11 when the spool 8 is in contact with the valve plate 16 is 0.
It becomes °.

A single-headed piston 19 is housed in a cylinder bore 1a penetrating the cylinder block 1 so as to be connected to the crank chamber 2a. A pair of shoes 20 is fitted in the neck portion 19 a of the single-headed piston 19. Swash plate 1
The peripheral edge portion of 1 enters between both shoes 20, and the end faces of both shoes 20 are in contact with both surfaces of the swash plate 11. Therefore, the swash plate 11
Is converted into forward and backward reciprocating swing of the single-headed piston 19 via the shoe 20, and the single-headed piston 19 moves back and forth in the cylinder bore 1a.

A suction chamber 3a and a discharge chamber 3b are defined in the rear housing 3. A suction port 16a and a discharge port 16b are formed on the valve plate 16, and a suction valve 17a and a discharge valve 17b are formed on the valve forming plate 17. Refrigerant gas in the suction chamber 3a is sucked into the suction port 16a by the backward movement of the single-headed piston 19.
From which the suction port 17a is pushed and flows into the cylinder bore 1a. The refrigerant gas flowing into the cylinder bore 1a is discharged from the discharge port 16b to the discharge chamber 3b by pushing the discharge valve 17b away from the discharge port 16b by the forward movement of the single-headed piston 19.
The discharge valve 17b comes into contact with the retainer 18a on the retainer forming plate 18 to regulate the opening degree.

The stroke of the single-headed piston 19 changes depending on the pressure difference between the pressure in the crank chamber 2a and the suction pressure in the cylinder bore 1a via the single-headed piston 19. That is, the tilt angle of the swash plate 11, which affects the compression capacity, changes. The pressure in the crank chamber 2a is controlled by the control valve 22 attached to the lower wall of the cylinder block 1 and the front housing 2. The crank chamber 2a and the suction chamber 3a communicate with each other through the throttle passage 1b.

The internal structure of the control valve 22 will be described with reference to FIGS. 4 and 6. A solenoid 24 and a fixed iron core 25 are housed and fixed in the solenoid housing 23. A guide rod 26 is slidably pierced and supported on the central axis of the fixed iron core 25. A movable iron core 27 is fixed to the guide rod 26 and can be brought into contact with and separated from the fixed iron core 25 by the guide action of the guide rod 26. The movable range of the movable iron core 27 is restricted between the fixed iron core 25 and the spring bearing 23 a of the solenoid housing 23. A spring bearing 26a is formed at one end of the guide rod 26, and a valve opening forced spring 49 is interposed between the spring bearing 26a and the end wall 23b of the solenoid housing 23. The movable iron core 27 is urged in the direction away from the fixed iron core 25 by the spring action of the valve opening forced spring 49.

A valve housing 28 is coupled and fixed to the solenoid housing 23, and the valve housing 2
A spherical valve element 29 is accommodated in the inside 8. The valve housing 28 is provided with a discharge pressure introducing port 28a, a suction pressure introducing port 28b and a control port 28c. The discharge pressure introducing port 28a communicates with the discharge chamber 3b through the discharge pressure introducing passage 30, and the suction pressure introducing port 28b communicates with the suction chamber 3a through the suction pressure introducing passage 31.
The control port 28c is connected to the crank chamber 2 via the control passage 32.
It communicates with a.

A return spring 33 is interposed between the end wall of the valve housing 28 and the valve body 29, and the valve body 29 receives the spring action of the return spring 33 in the direction of closing the valve hole 28d. When the valve hole 28d is closed, the discharge pressure introducing port 28
The communication between a and the control port 28c is cut off.

A diaphragm 34 is interposed between the solenoid housing 23 and the valve housing 28. A pressing rod 35 is slidably accommodated in the valve housing 28 so as to always shut off the suction pressure introducing port 28b and the control port 28c. Push rod 3
One end of 5 is fixed to the diaphragm 34. A pressing spring 50 is interposed between the spring receiver 23a and the diaphragm 34. The pressure spring 50 opposes the suction pressure via the diaphragm 34. The pressing rod 35 is the pressing spring 5.
The spring action of 0 always makes contact with the valve element 29.

As shown in FIG. 4, when the valve element 29 closes the valve hole 28d and the movable iron core 27 is in contact with the fixed iron core 25, that is, when the solenoid 24 is in the excited state, the guide rod 26 is It is slightly separated from the diaphragm 34. When the solenoid 24 is demagnetized, the movable iron core 27 contacts the spring receiver 23a by the spring action of the valve opening forced spring 49 as shown in FIG. In this abutting state, the guide rod 26 pushes the pressing rod 35 toward the valve body 29, and the valve opening of the valve body 29 becomes maximum.

The solenoid 24 and the tilt-returning electromagnetic solenoid 36 are both excited and demagnetized by the control computer C. A rotation detector 3 is provided in the front housing 2.
9 are installed. The rotation detector 39 detects the rotation of the rotary support 5, and this detection signal is sent to the control computer C. When the control computer C receives the rotation stop detection signal from the rotation detector 39, the control computer C commands the demagnetization of the solenoid 24 and the tilt return electromagnetic solenoid 36.

An inlet 1d for introducing the refrigerant gas into the suction chamber 3a and an outlet for discharging the refrigerant gas from the discharge chamber 3b are connected by an external refrigerant circuit 40. External refrigerant circuit 40
A condenser 41, an expansion valve 42, and an evaporator 43 are provided above. The expansion valve 42 controls the refrigerant flow rate according to the fluctuation of the gas pressure on the outlet side of the evaporator 43.

A temperature sensor 44 is installed on the outlet side of the evaporator 43. The temperature sensor 44 detects the temperature on the outlet side of the evaporator 43, and this detection signal is sent to the control computer C. When the control computer C obtains the temperature detection information below the predetermined temperature from the temperature sensor 44, the solenoid 24
And commanding demagnetization of the electromagnetic solenoid 36 for tilt angle recovery.

An air conditioner operation switch 45, an air conditioner stop switch 46, an accelerator switch 47 and an outside air temperature sensor 48 are signal-connected to the control computer C. The control computer C turns on the solenoid 2 by turning on the air conditioner operation switch 45 and turning off the accelerator switch 47.
4 and the command to energize the electromagnetic solenoid 36 for tilt angle return. Further, the control computer C commands the demagnetization of the solenoid 24 and the tilt angle recovery electromagnetic solenoid 36 by turning on the air conditioner stop switch 46 and the accelerator switch 47. Further, when the control computer C obtains the temperature detection information below the predetermined temperature from the outside air temperature sensor 48, the solenoid 24
And commanding demagnetization of the electromagnetic solenoid 36 for tilt angle recovery.

In the state of FIG. 1, the air conditioner operation switch 45
Is ON, and the solenoid 24 and the tilt angle returning electromagnetic solenoid 36 are both in the excited state. Solenoid 2
4, the movable iron core 27 is attracted to the fixed iron core 25, and the guide rod 26 is separated from the diaphragm 34. Under this separated state, the diaphragm 34 is displaced according to the fluctuation of the suction pressure introduced from the suction pressure introducing port 28b, and this displacement is transmitted to the valve body 29 via the pressing rod 35. When the suction pressure is high (the cooling load is large), the diaphragm 34 bends and deforms toward the guide rod 26 side against the spring action of the pressing spring 50, and the valve body 2
The valve opening of 9 becomes small. When the pressure in the crank chamber 2a is higher than the suction pressure, the refrigerant gas in the crank chamber 2a flows into the suction chamber 3a via the throttle passage 1b. Therefore, if the valve opening of the valve element 29 becomes smaller, the crank chamber 2a
The internal pressure decreases and the swash plate tilt angle increases. On the contrary, when the suction pressure is low (the cooling load is small), the diaphragm 34 is bent and deformed toward the valve body 29 by the spring action of the pressing spring 50, and the valve opening degree of the valve body 29 increases. Therefore,
The pressure in the crank chamber 2a rises and the swash plate inclination angle becomes smaller.

Since the electromagnetic solenoid 36 for returning the tilt angle is excited, the spool 8 is separated from the valve plate 16, and the end surface of the large-diameter cylindrical portion 8a of the spool 8 projects into the crank chamber 2a. Therefore, the tilt angle of the swash plate 11 is restricted between the maximum tilt position in which the swash plate support 10 abuts on the spool 8 and the minimum tilt position in which the swash plate support 10 abuts on the spool 8. That is, the discharge capacity is controlled within this tilt angle range of the swash plate 11, and the discharge capacity does not become zero.

The control computer C sends a rotation stop detection signal from the rotation detector 39, a detection signal below a predetermined temperature from the temperature sensor 44, and an ON state from the air conditioner stop switch 46.
Based on the signal, the ON signal from the accelerator switch 47, or the detection signal from the outside air temperature sensor 48 at a predetermined temperature or lower, the solenoid 24 and the tilt angle returning electromagnetic solenoid 36 are demagnetized. That is, each of these detection signals becomes an external control signal to the control valve 22 which is a tilt angle compulsory changing means for changing the pressure in the crank chamber to make the swash plate tilt angle zero. And
The rotation detector 39, the temperature sensor 44, the air conditioner stop switch 46, the accelerator switch 47, or the outside air temperature sensor 4
8 is an external control signal generator.

When the solenoid 24 is demagnetized, the movable iron core 27
Is separated from the fixed iron core 25 by the spring action of the valve opening forced spring 49 and abuts on the spring receiver 23a. This movable iron core 2
The movement of 7 maximizes the valve opening of the valve element 29, and the pressure in the crank chamber 2a rises sharply. Further, when the tilt return electromagnetic solenoid 36 is demagnetized, the spool 8 moves and abuts on the valve plate 16 by the spring action of the return spring 21. Due to this moving contact, the end surface of the large-diameter cylindrical portion 8a coincides with the end surface of the cylinder block 1. Therefore, as shown in FIG. 5, the tilting angle of the swash plate 11 immediately becomes 0 ° due to the sudden pressure increase in the crank chamber 2a and the movement of the spool 8. Therefore, the discharge capacity becomes zero, and the same state as the compressor unloaded state when the clutch is disengaged in the clutch-mounted compressor can be obtained. This compressor no-load condition directs the full power of the vehicle engine to drive the vehicle.

Even if the compressor is operated with the swash plate 11 having an inclination of 0 °, the discharge capacity becomes zero, so that the refrigerant gas pressure in the compressor and in the external refrigerant circuit becomes uniform. for that reason,
The swash plate 11 cannot be tilted by lowering the pressure in the crank chamber 2a. In the present embodiment, the swash plate 11 is tilted by exciting the tilt return electromagnetic solenoid 36.

When the air conditioner operation switch 45 is turned on, the control computer C causes the temperature sensor 44 to detect a detection signal of a predetermined temperature or higher, and the accelerator switch 47 to set O.
Based on the FF signal or the detection signal from the outside air temperature sensor 48 which is equal to or higher than the predetermined temperature, the solenoid 24 and the tilt angle returning electromagnetic solenoid 36 are excited. The spool 8 is separated from the valve plate 16 by the excitation of the electromagnetic solenoid 36 for returning the tilt angle, and the end surface of the large-diameter cylindrical portion 8a projects from the end surface of the cylinder block 1. Due to this protrusion, the swash plate support 10 moves to the rotation support 5 side, and the swash plate 11 tilts as shown in FIG. 7. Therefore, the single-headed piston 19 starts reciprocating motion, and the discharging action is performed.

The degree of inclination of the swash plate 11 at this time brings about the minimum discharge capacity of about 10% of the maximum discharge capacity.
That is, the movable iron core of the tilt-returning electromagnetic solenoid 36 is arranged so that the swash plate support 10 is arranged at a position where the swash plate tilt angle is zero (the discharge capacity is zero) and the minimum discharge capacity is about 10% of the maximum discharge capacity. 38 stroke ranges are set.

When the swash plate 11 starts to rotate from the state where the inclination angle of the swash plate 11 is maximum, the starting shock is transmitted to the vehicle engine side, and the sensible feeling is deteriorated. Starting the swash plate 11 from the swash plate tilt angle that provides the minimum capacity of FIG. 7 mitigates the starting shock.

The movable iron core 27 is attracted to the fixed iron core 25 by exciting the solenoid 24 at the same time as exciting the tilt return electromagnetic solenoid 36. Due to this suction, the guide rod 26 is separated from the diaphragm 34, and the diaphragm 34 is displaced according to the fluctuation of the suction pressure introduced from the suction pressure introducing port 28b. That is, the tilt angle of the swash plate 11 returns to the tilt angle that produces the minimum discharge action, and at the same time, the tilt angle of the swash plate 11 is controlled based on the suction pressure that reflects the cooling load.

In this embodiment, the rotation detector 39, the temperature sensor 44, the air conditioner stop switch 46, the accelerator switch 47, and the outside air temperature sensor 48 are used to control the excitation / demagnetization of the control valve 22 that serves as the inclination angle forced change means. In addition to these, for example, a pressure sensor for detecting the refrigerant gas pressure or a cooling water temperature sensor for a vehicle engine is also a target of the external control signal generator.
When the detected pressure obtained from the pressure sensor is out of the predetermined upper and lower limit ranges, the control valve 22 and the tilt angle return electromagnetic solenoid 36 are excited to make the tilt angle of the swash plate 11 zero. When the detected pressure is within the predetermined upper and lower limits, the control valve 2
2 and declination electromagnetic solenoid 36 for declination, swash plate 1
Restore the tilt angle of 1.

The embodiment shown in FIG. 8 is also possible as a structure for restoring the inclination angle of the swash plate. In this embodiment, the movable iron core 27
Is transmitted to the spool 8 via the lever 51.
Support shaft 5 between the force point 51a and the action point 51b of the lever 51
When 2 is brought closer to the action point 51b side, the suction force of the fixed iron core 25 against the movable iron core 27 increases and acts on the spool 8. When the suction force of the solenoid 24 is weak, this boosting structure is effective. When the support shaft 52 is brought closer to the power point 51a side, the stroke of the movable iron core 27 is expanded and the spool 8
Be transmitted to. When the stroke of the movable iron core 27 is small, this stroll enlargement configuration is effective.

[0040]

As described in detail above, according to the present invention, the pressure in the crank chamber is changed based on the external control signal output from the external control signal generator so that the swash plate inclination angle becomes zero, and the swash plate tilt angle becomes zero. Since the swash plate support at the position where the swash plate tilt angle is zero is moved in the direction of increasing the tilt angle of the swash plate when restarting the discharge,
It is possible to achieve the compressor no-load state while the external power is being transmitted to the rotary shaft of the compressor, and further, it is possible to restart the discharge even after the compressor no-load state.

Further, the discharge pressure introducing port communicating with the discharge pressure region, the suction pressure introducing port communicating with the suction pressure region, the control port communicating with the crank chamber, and the valve hole connecting the discharge pressure introducing port and the control port are opened and closed. Valve body, a return spring for urging the valve body in the direction of closing the valve hole, a pressure sensitive body for urging the valve body in the direction of opening the valve hole by suction pressure, and a direction of opening the valve body in the direction of opening the valve hole. In the invention in which the tilt angle compulsory changing means for making the swash plate tilt angle to zero is constituted by the electromagnetic solenoid that drives the pressure sensitive body in the biasing direction, the normal swash plate tilt angle control can also be performed by this tilt angle compulsory changing means. It has an excellent effect.

[Brief description of 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.

FIG. 4 is a side sectional view of a control valve that serves as a tilt angle forced change means.

FIG. 5 is a side sectional view showing a state where the discharge capacity is zero.

FIG. 6 is a side sectional view of the control valve in a demagnetized state.

FIG. 7 is a side sectional view showing a minimum discharge capacity state.

FIG. 8 is a side sectional view of a main part showing another example of the tilt angle returning means.

[Explanation of symbols]

2a ... Crank chamber, 3a ... Suction chamber serving as suction pressure region, 3
b ... Discharge chamber serving as discharge pressure region, 5 ... Rotation support, 6 ... Rotation shaft, 8 ... Spool, 10 ... Swash plate support, 11 ... Swash plate,
Reference numeral 19 ... Single-headed piston, 21 ... Return spring, 22 ... Control valve serving as inclination angle changing means, 24 ... Solenoid, 28a ... Discharge pressure introducing port, 28b ... Suction pressure introducing port, 28c ...
Control port, 28d ... Valve hole, 29 ... Valve body, 33 ... Return spring, 34 ... Diaphragm serving as pressure sensitive body, 36 ... Inclination return electromagnetic solenoid 36.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ken Mizuto 2-1-1 Toyota-cho, Kariya city, Aichi stock company Toyota Industries Corp.

Claims (2)

[Claims] 1. A swash plate support on a rotating shaft in a housing that defines a crank chamber, a suction chamber, a discharge chamber, and a cylinder bore connecting these chambers, and accommodates a single-head piston in a reciprocating linear motion in the cylinder bore. Is slidably supported, the swash plate is tiltably supported on the swash plate support, and the swash plate is tiltably linked to the rotary support on the rotating shaft.
In a one-sided piston variable displacement compressor that controls the tilt angle of the swash plate by the difference between the pressure in the crank chamber and the suction pressure via a single-headed piston, in the crank chamber based on the external control signal output from the external control signal generator. An inclination forcible changing means for changing the pressure to make the swash plate inclination angle zero, and a swash plate inclination angle for moving the swash plate support at a position where the swash plate inclination angle is zero on the rotation axis in the direction of increasing the swash plate inclination angle. A return means is provided, and a discharge pressure introducing port communicating with the discharge pressure region, an intake pressure introducing port communicating with the intake pressure region, a control port communicating with the crank chamber, and a valve hole connecting the discharge pressure introducing port and the control port are provided. A valve body that opens and closes, a return spring that biases the valve body in the direction of closing the valve hole, a pressure-sensitive body that biases the valve body in the direction of opening the valve hole by suction pressure, and a valve hole that opens the valve body. Drive the pressure sensitive element in the direction Clutchless structure on one side a piston type variable displacement compressor which constitutes the tilt force changing means by an electromagnetic solenoid for. 2. A swash plate tilt return means is housed in a cylinder block which houses a single-headed piston, and is a slidable plate which supports slidable and relatively rotatable rotary shafts. The clutchless structure for a one-sided piston variable displacement compressor according to claim 1, comprising elastic means for urging the elastic member in a direction away from the elastic means, and an electromagnetic solenoid for driving the spool in a direction opposite to the elastic means.