JPH03134268A - Variable displacement swash plate type compressor - Google Patents

Abstract

PURPOSE:To reduce pressure hunting without deteriorating an acceleration character by providing a check valve type regulating valve, having a function of throttling a high pressure from a high pressure introducing passage, in a signal pressure passage for guiding the high pressure to a control pressure chamber through the high pressure introducing passage. CONSTITUTION:A check valve type regulating valve, having a function of throttling a high pressure supplied from a high pressure introducing passage 96, is provided in a signal pressure passage 98 for guiding the high pressure to a control pressure chamber 200, formed in the back surface of a spool 30, through the high pressure introducing passage 96. By this constitution, in the case of introducing the high pressure to the control pressure chamber 200, formed in the back surface of the spool 30, through the high pressure introducing passage 96, a flow amount can be limited by throttling action of the check valve type regulating valve with reduction made possible of pressure hunting. Further in the case of transfer to a low displacement, because no throttling action is performed by the check valve type regulating valve, the transfer is promptly performed to the low displacement without deteriorating an acceleration character.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to capacity control of a swash plate compressor that is effective for use as a refrigerant compressor for, for example, an automobile air conditioner.

[Prior Art] The present inventors first attached a swash plate to a shaft in a swingable manner, varied the inclination angle of the swash plate in accordance with the displacement of the spool, and simultaneously displaced the center position of the swash plate. We proposed a variable displacement swash plate type compressor.

In this swash plate type compressor, the spool is displaced according to the pressure in the control pressure chamber formed on the back of the spool, and the tilt angle of the swash plate and the center position of the swash plate are simultaneously displaced in response to the displacement of the spool. It was designed so that The control pressure introduced into the control pressure chamber is adjusted by a control valve.

By the way, the suction side pressure of the compressor changes depending on the load of the refrigeration cycle, so the control valve adjusts the signal pressure supplied to the control pressure chamber on the back of the spool based on the change in this suction side pressure. adjust.

However, if the spool is displaced in response to changes in the suction side pressure and the discharge capacity of the compressor is controlled thereby, the capacity of the compressor will be adjusted so that the suction side pressure is always constant. It will be controlled. Here, the fact that the suction/side pressure is always constant means that the evaporation temperature of the evaporator in the refrigeration cycle is always kept constant.

However, when the load on the refrigeration cycle suddenly changes, better control can be achieved by actively varying the evaporation temperature rather than by controlling the evaporation temperature of the evaporator to be constant. There are many cases where

Therefore, the present inventors decided to control the discharge capacity of the compressor, that is, the displacement of the spool, basically based on the displacement of the suction side pressure of the compressor, and to control the displacement of the compressor based on the displacement of the suction side pressure of the compressor. We proposed a compressor that can be controlled based on

In other words, this compressor functions as a control valve that controls the signal pressure guided to the control pressure chamber formed on the back of the spool, and controls the low pressure introduced via the low pressure introduction passage and the high pressure introduced via the high pressure introduction passage. A control valve body is provided to adjust the signal pressure between the two, and the control valve body is driven by the displacement of a diaphragm that changes according to the displacement of the pressure on the low pressure side of the compressor. The displacement of the diaphragm can also be controlled based on the magnetic force generated by the solenoid.

By adopting such a configuration, the control valve body is basically controlled based on fluctuations in the pressure on the low pressure side of the compressor, but it is also possible to control the control valve body based on the magnetic force of the solenoid. Can be done.

[Problems to be Solved by the Invention] However, in such a configuration, a discharge pressure change @ (pulsation) occurs in the high pressure introduced from the high pressure introduction passage to the control pressure chamber via the signal pressure passage. Further, depending on the duty ratio of the solenoid, vibrations of the valve may occur when the control valve body behaves, and such fluctuations cause pressure hunting in the control pressure chamber.

Such pressure hunting induces hunting in the ζ capacity control, which has the disadvantage of deteriorating the driving feeling and cooling feeling.

Therefore, an object of the present invention is to reduce pressure hunting in a control pressure chamber, and in this case, reduce the pressure hunting without impairing acceleration (that is, without taking time to shift to a low capacity). The present invention aims to provide a variable displacement swash plate compressor that reduces the

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a signal pressure passage that leads high pressure to a control pressure chamber formed on the back surface of the spool via a high pressure introduction passage, which is supplied from the high pressure introduction passage. The present invention is characterized in that it is equipped with a check valve type regulating valve that has the function of restricting the high pressure generated.

C Effect] According to such a configuration, when high pressure is introduced to the control pressure chamber formed on the back surface of the spool through the high pressure introduction passage,
The above check valve type: Since the flow rate is restricted by the throttling action of the J8 regulating valve, pressure loss can be reduced. Furthermore, when shifting to a low capacity, the check valve type regulating valve does not exert a throttling action, so that the shift to a low capacity is rapid, and acceleration performance is not impaired.

[Example] The present invention will be described below based on an example shown in FIGS. 1 to 5.

FIG. 51 is a longitudinal sectional view of a variable displacement swash plate compressor. In the figure, reference numeral 7 indicates a main body forming the outer shell of the compressor. This main body 7 includes a front housing 4 made of aluminum alloy, a front side plate 8, an intake valve 9, a front cylinder block 5, a rear cylinder block 6, and an intake valve 1.
2. The rear side plate 11 and the rear housing 13 are integrally fixed by through bolts (not shown).

The cylinder block 5.6 has cylinders 64 as shown in FIG.
5 are formed, and these cylinders 64... are formed to be parallel to each other.

A shaft 1, which rotates under the driving force of an automobile engine (not shown), is rotatably supported by a front housing 4 and a front cylinder block 5 via bearings 2 and 3, respectively. The force acting on the shaft 1 in the left direction in the figure is the thrust bearing 1
The shaft 1 is received by the front cylinder block 5 via the shaft 1, and the movement of the shaft 1 in the right direction in the figure is restricted by a retaining ring 16. Note that the retaining ring 16 is locked in an annular groove formed in the shaft 1.

Opposed to the shaft 1, a rear shaft 40 is rotatably supported by a spool 30 via a bearing 14. The thrust force acting on the rear shaft 40 in the right direction in the figure is received by the spool 30 via the thrust bearing 116, and the leftward movement of the rear shaft 40 is received by the spool 30 by the retaining ring 17. This prevents the rear shaft 40 from coming off the spool 30. Note that this retaining ring is also locked in an annular groove formed in the rear shaft 40.

The spool 30 includes a cylindrical portion 65 formed on the rear cylinder block 6 and a cylindrical portion 1 formed on the rear housing 13.
35 so as to be slidable in the axial direction.

Reference numeral 10 denotes a swash plate, and a spherical part 107 is formed in the center of the swash plate 10. A spherical support part 405 fixed to the end of the rear shaft 40 is disposed on this spherical part 107. The swash plate 10 is supported by this ball support portion 405 in a swingable state.

A slit 105 is formed on the side surface of the swash plate 10 facing the shaft 1;
A flat plate portion 165 is formed on the end face facing the swash plate 10 . By disposing the flat plate portion 165 in surface contact with the inner wall of the slit 105, the shaft 1
This is to transmit the rotational driving force applied to the diagonal 1flo.

Furthermore, shoes 18 and one shoe are slidably disposed on both sides of the swash plate 10.

On the other hand, a piston 7 is slidably disposed within a cylinder 64 formed across the front cylinder block 5 and rear cylinder block 6.

Shoe 1 slidably attached to the swash plate 10
8 and 19 are rotatably engaged with the inner surface of the piston 7. Therefore, the rocking motion accompanying the rotation of the swash plate 10 is transmitted through these shoes 18 and one of the pistons 7...
・It is transmitted as a reciprocating motion to.

A long groove 166 is provided in the one 1i-plate portion 165 of the shaft 1, and a pin hole is formed in the swash plate 10. After the flat plate portion 165 of the shaft 1 is placed in the slit 105 of the swash plate 10, the pin 80 and a ring (not shown) are used to fit the pin through hole and the long groove 166 of the shaft 1.
It is locked with. The inclination of the swash plate changes depending on the position of the pin 80 in the long groove 166, and as the inclination changes, the position of the center of the swash plate (the ball support portion 405 of the spherical portion 107) also changes.

That is, in the second working chamber 60 on the right side in FIG.
The long groove 166 is provided so that even if the inclination of the swash plate 10 changes and the stroke of the piston 7 changes, the top dead center of the piston 7 on the working chamber 60 side will hardly change and the dead volume will not substantially increase. ing. On the other hand, in the working chamber 50 on the left side in the figure, the inclination of the swash plate changes and the top dead center of the piston 7 changes, so the dead volume also changes.

In this embodiment, as described above, the long groove 166 is formed in such a shape that even if the inclination angle of the swash plate 10 changes, the top dead center position of the piston 7 on the working chamber 60 side does not change. Therefore, strictly speaking, the long groove 166 has a curved shape, but its actual shape can be approximated by a substantially straight long groove. Furthermore, in this embodiment, the shape of the long groove 166 allows the flat plate portion 165 to
The long groove 166 is arranged on the axis of the shaft 1 so that the shape of the shaft 1 does not become excessively large. Like this long groove 1
66 on the axis of the shaft 1 to reduce the size of the flat plate portion 165 is particularly effective in a swash plate type compressor in which the flat plate portion 165 is disposed inside the piston 7.

Reference numeral 21 denotes a shaft sealing device, which prevents refrigerant gas and lubricating oil from leaking to the outside along the shaft 1.

Reference numeral 24.24 indicates a discharge port that opens into the first and second working chambers 50 and 60 and communicates with the discharge chambers 90 and 93, respectively. It is opened and closed by Discharge valve 22.22
The front side plate 8 and the rear side plate 11 are attached to the front side plate 8 and the rear side plate 11 by bolts (not shown) together with the valve retainers 23 and 23.
Fixed.

Reference numerals 25 and 25 indicate the first and second working chambers 50 and 60.
and suction chambers 72 and 74, which are opened and closed by suction valves 9 and 12, respectively.

The front side discharge space 90 is led to a discharge port 92 through a discharge passage 91 formed in the cylinder block 5, and the rear side discharge space 93 is led to a discharge port 92 through a discharge passage 94 formed in the cylinder block 6. I am guided by 95.

Since these discharge ports 92 and 95 are communicated with each other by external piping, the pressures in the discharge space 90 and the discharge space 93 are the same pressure.

Further, the front side suction space 72 is guided by a suction passage 71 to a suction space 70 formed in the center of the housing, and the rear side suction space 74 is also guided to the suction space 70 by a suction passage 73.

In addition, the reference numerals 51, 52, 53, 54, 55°56 in the figure are O-rings.

Reference numeral 400 is a control valve for controlling the pressure within the control pressure space 200, and is controlled by a control circuit 500.

FIG. 3 shows this control valve 400, and 401 in the figure is a control valve housing. This control valve housing 401
is attached to the rear side of the rear housing 13,
Also, within this control valve housing 401, a discharge space 93 is provided.
A high pressure introduction passage 96 communicating with the intake space 74, a low pressure introduction passage 97 communicating with the suction space 74, and a signal pressure passage 98 communicating with the control pressure chamber 200 are formed.

In this control valve housing 401, a valve seat member 4 is provided.
02 has been inserted. The high pressure introduction passage 96 is formed penetrating inside the valve seat member 402, and this high pressure introduction passage 96 communicates with the signal pressure passage 98 at the inner end of the valve seat member 402. The valve seat member 402 has a first
A control valve body 403 made of a ball valve or the like is arranged at a position facing the first valve seat surface 404 . This control valve body 403 is connected to the first valve seat surface 4
04, the signal pressure passage 98 and the high pressure introduction passage 96 are cut off.

On the other hand, a second valve seat surface 405 is formed in the valve housing 401 at a position facing the control valve body 403, and a low pressure introduction passage 97 is opened in the second valve seat surface 405. Therefore, the control valve body 403 is
05, conduction between the signal pressure passage 98 and the low pressure introduction passage 97 is cut off.

A connecting rod 406 is provided on the second valve seat surface 405 side of the control valve body 403.
is slidably passed through the connecting rod 406, and the connecting rod 406 is connected to a diaphragm 410.

Therefore, the displacement of diaphragm 410 is
The signal is transmitted to the control valve body 403 via the control valve body 403.

The periphery of the diaphragm 410 is held between the control valve nozzle housing 401 and a guide ring 411 fixed to this end. Also, this diaphragm 410
The center portion of is held between the connecting rod 406 and the slide member 412 described above.

A suction pressure chamber 413 is formed on one side of the diaphragm 410, and the refrigerant pressure in the suction space 74 is introduced into the suction pressure chamber 413 via a low pressure introduction passage 97.

The slide member 412 slidably passes through a closing wall member 415 provided at one end of the solenoid housing 414 and comes into contact with a plunger 416 . An adjustment screw 417 is screwed onto the other end of the solenoid housing 414, and a spring 418 is disposed between the adjustment screw 417 and the plunger 416.

This biasing force of the biasing spring 418 and the diaphragm 4
Depending on the magnitude of the force generated by the pressure difference between the two sides of the connecting rod 406, the connecting rod 406 is displaced in the left-right direction in the figure. The biasing force of the spring 418 is determined by the adjustment screw 41.
Adjusted by 7.

The plunger 416 is slidably housed in a cylindrical member 421 made of a magnetic material, and a solenoid coil 420 is disposed in the magnetic cylindrical member 421.

Therefore, when the coil 420 is excited, the plunger 416 is displaced to the left in the figure.

Although not shown, the control circuit 500 adjusts an output voltage according to signals from an accelerator sensor, an evaporator outlet temperature sensor, and an indoor temperature sensor, and this output voltage is exchanged into a current value by a current adjustment means. This signal current is applied to the solenoid coil 420 of the control valve 400.

Signal pressure passage 98 formed in the control valve housing 401
is provided with a check valve type regulating valve 600 that prevents pressure cutting in the control pressure chamber 200.

That is, a valve chamber 601 is formed in the opening of the signal pressure passage 98 facing the control pressure chamber 200 side.

A valve seat body 603 with a valve hole 602 opened is attached to the open end of the valve chamber 601 facing the control pressure chamber 200 . Further, a seat portion 604 having a larger diameter than the valve hole 602 is formed in the shoulder portion at the back of the valve chamber 601 .

A disk-shaped check valve body 605 made of, for example, Teflon is accommodated in the valve chamber 601 and is slidable between the valve seat body 603 and the seat portion 604 . The center of this check valve body 605 has a diameter of, for example, 0.5 to 1. A throttle hole 606 with a diameter of Off1m is formed, and around this throttle hole 606, for example, four through holes 60 with a diameter of 1.0a+m or more are formed.
7... is formed.

When the check valve body 605 is seated on the valve seat body 603,
The four through holes 607 formed around the valve seat body 6
03, and in this case, the control pressure chamber 20
0 and the signal pressure passage 98 communicate only through the central throttle hole 606. When the check valve body 605 is separated from the valve seat body 603 and is seated on the seat portion 604, the four through holes 607 formed around the above are not closed, and therefore the control pressure chamber 200 and the signal pressure passage 98 is connected to the throttle hole 60.
6 and all four through holes 607.

The operation of the compressor with the above configuration will be described.

When an electromagnetic clutch (not shown) is connected and driving force from the engine is transmitted to the shaft 1, the compressor starts.

At startup, the pressure is balanced inside the compressor, so there is no pressure difference before and after the spool 30. That is,
At the time of startup, no load is applied via the support portion 107 in a direction that makes the swash plate 10 tilt.

When the shaft 1 starts rotating in this state, the rotation of the shaft 1 drives the piston 7 to reciprocate via the swash plate 10. As the piston 7 reciprocates, the working chamber 50.6
The refrigerant is sucked, compressed, and discharged within 0.

However, in this case, the force based on the pressure difference between the second working chamber 60 on the rear side and the first working chamber 50 on the front side is applied to the piston 7.
and will be applied to the swash plate 10 via shoes 18,19. In particular, the swash plate 10 is swingably supported by the spherical support part 405, and the slit 105 and the flat plate part 1
Since the rotational force of the shaft 1 is received by the fitting with the piston 65, the force applied to the piston 7 acts as a moment in the direction of decreasing the inclination angle of the swash plate 10.

For example, when the pin 80 is located on the axis X shown in FIG. , a rotational moment is generated from the pistons 7 disposed in the second to fifth cylinder spaces 642, 643, 644, 645 in a direction that reduces the inclination angle of the swash plate 10. This rotational moment is
It will be affected by the moment generated around . Further, the rotational moment generated by the piston 7 applies a pressing force to the spherical support portion 405.

That is, when the control valve 400 introduces suction pressure into the control pressure chamber 200, the spherical support portion 405 and the spool 3
0 is displaced to the right in the figure.

As a result, the swash plate 10 reduces its angle of inclination.

However, the swash plate 10 is connected to the long groove 166 of the shaft 1 and the pin 80.
Therefore, the inclination of the swash plate 10 is reduced, and a force is applied to the ball portion 405 at the center of the swash plate 10 in the right direction in the figure, thereby moving the ball portion 405 to the right. The force acting in the right direction in the figure on the rear shaft 40 via the spherical support portion 405 is transferred to the spool 3 via the thrust bearing 16.
0, and the spool 30 moves until it hits the bottom of the rear housing 13. This state is the state in which the discharge capacity of the compressor is at its minimum.

Then, the refrigerant gas sucked through a suction port (not shown) (connected to the evaporator of the refrigeration cycle) enters the central suction space 70, then passes through the suction passages 71 and 73.
Enter the front and rear suction chambers 72 and 74. after that,
During the suction stroke of the piston 7, air is sucked into the working chamber 50, 60 from the suction port 25 via the suction valve 12.

The sucked refrigerant gas is compressed in a compression stroke, and when compressed to a predetermined pressure, the discharge valve 22 is pushed open through the discharge port 24 and discharged into the discharge chamber 90.93.

The high-pressure refrigerant gas passes through a discharge passage 91.94 and is discharged from a discharge port 92.95 to a condenser (not shown) of the refrigeration cycle.

At this time, since the first working chamber 50 on the front side has a large dend volume, the compression ratio is smaller than that of the second working chamber 60 on the rear side (the pressure of the refrigerant gas in the first working chamber 50 is lower than that of the second working chamber 60 on the rear side). Since the pressure in the space 90 is lower than the pressure in the space 90 (to which the discharge pressure of the second working chamber 60 on the rear side is led), the suction and discharge of refrigerant gas are not performed in the first working chamber 50 on the front side.

When starting the compressor, the discharge capacity of the compressor is set to the minimum capacity as described above.

However, when the capacity of the compressor required from the refrigeration cycle side is high, high pressure side pressure is introduced into the control pressure chamber 200.

It is known that the load required of the compressor, that is, the load of the refrigeration cycle, affects the compressor suction side pressure, and when the cooling load is large, the evaporator generates a large amount of superheat, and the compressor The suction side pressure of increases. Conversely, it is known that when the cooling load is small, the pressure on the suction side of the compressor decreases.

Therefore, when the capacity required of the compressor is high, the suction side refrigerant pressure becomes high, and this pressure is introduced into the suction pressure chamber 413 in FIG. 3 through the low pressure introduction passage 97. Become. Therefore, the biasing force applied to the diaphragm 410 increases, overcomes the biasing force of the biasing spring 418, and displaces the slide member 412 to the right in FIG. 3. The third connecting rod 406 receives this displacement.
Displaced to the right in the figure.

As a result, the control valve body 403 receives pressure from the high pressure introduction passage 96 and comes into contact with the second valve seat surface 405 . Therefore, the conduction between the low pressure introduction passage 97 and the signal pressure passage 98 is cut off.

On the other hand, as the control valve body 403 is displaced, the first valve seat surface 404 opens, and the high pressure introduction passage 96 and the signal pressure passage 98 are brought into communication. Therefore, high pressure from the high pressure introduction passage 96 side is introduced into the signal pressure passage 98, and as a result, the pressure within the control pressure chamber 200 also increases.

Therefore, a force acting on the spool 30 in the left direction in FIG. 1 (due to the pressure difference between the control pressure chamber 200 and the suction space 74)
gradually increases as the compressor rotates. When this force overcomes the force pushing the spherical support portion 405 to the right in the figure, the spool 30 gradually begins to move to the left in the figure.

Then, due to the action of the long groove 166 of the shaft 1 and the pin 80, the swash plate 10 moves its center of rotation (spherical support portion 405) to the left in the figure and increases its inclination.

As the pressure within the control pressure chamber 200 further increases, the spool 30 moves to the left in the figure until its shoulder 305 touches the rear side plate 11, achieving the maximum capacity state.

This is the state shown in FIG. 1. In the state shown in FIG. 1, refrigerant gas sucked from a suction boat (not shown) enters the central suction space 7o, passes through suction passages 71 and 73, and enters the suction chambers 72 and 74, respectively. flow into. In the suction stroke, it enters the working chambers 50 and 60 from the suction port 25 via the suction valves 9 and 12, respectively, and then the piston 7
is compressed with the displacement of , enters the discharge spaces 9o and 93 from the discharge port 24 through the discharge valve 22, passes through the discharge passages 91 and 94, and is discharged into the discharge boats 92 and 95.
It is discharged from the pipe and joins with the external piping. In this state, both the working chamber 5o and the working chamber 60 are performing the action of sucking and discharging refrigerant gas.

In this way, in the compressor of this embodiment, when the suction side pressure is high, the signal pressure passage 98 is communicated with the high pressure introduction passage 96 to increase the pressure in the control pressure chamber 200, thereby increasing the pressure of the compressor. Increase capacity up to 8 melons.

As a result, if the discharge capacity of the compressor exceeds the required capacity, the cooling load becomes relatively small, and as a result, the suction side pressure decreases.

When the suction side pressure decreases, the pressure introduced into the suction pressure chamber 413 through the low pressure introduction passage 97 decreases, and the diaphragm 410 is displaced to the left in FIG. 3 due to the biasing force of the biasing spring 418. . This diaphragm 410
The displacement is transmitted to the control valve body 403 via the connecting rod 406, and the control valve body 403 separates from the second valve seat surface 405.

Therefore, the signal pressure passage 98 is brought into communication with the low pressure introduction passage 97, and as a result, the pressure within the control pressure chamber 200 escapes to the low pressure introduction passage 97 side.

In this way, if the pressure introduced into the control pressure chamber decreases, the spool 30 will also be displaced accordingly.

As mentioned above, the compressor capacity is controlled according to the displacement of the spool, so when the suction side pressure is low, the discharge capacity of the compressor decreases, and as a result, the discharge capacity corresponds to the load of the refrigeration cycle. capacity.

By repeating the above operations, the discharge capacity of the compressor of this example is controlled so that the suction side pressure is always constant.

However, in the compressor of this example, it is possible to perform not only control to keep the suction pressure constant, but also control to actively change the suction pressure depending on the capacity required of the compressor.

That is, in the above description, the biasing force of the biasing spring 418 is constant, but by adjusting the excitation force of the coil 420, the biasing force of the biasing spring 418 can be variably controlled. For example, if the flow rate of air flowing into the evaporator of a refrigeration cycle increases, or if the temperature of the air sucked into the evaporator increases, the load fluctuation will be reflected in the suction pressure chamber as a change in suction pressure. In addition to changing the pressure within 413, the output of control circuit 500 is also changed in response to the signal from the evaporator outlet temperature sensor.

When the coil 420 is excited in response to a signal from the control circuit 500, the plunger 416 is displaced to the left in FIG. This increases the biasing force of the biasing spring 418 and, as a result, increases the pressure in the suction pressure chamber 413 that balances the control valve body 403. If the discharge capacity of the compressor is variably controlled based on the suction side pressure while the biasing force of the biasing spring 418 is relatively strong, the suction side pressure at the balanced position will become high.

Here, since the suction side pressure of the compressor almost matches the evaporation pressure of the evaporator in the refrigeration cycle, an increase in the suction side pressure increases the evaporation temperature of the refrigerant in the evaporator. Therefore, by increasing the balanced suction pressure, the temperature of the air discharged from the evaporator can be increased as a result.

As described above, the compressor of this embodiment has a self-adjustment function of the compressor capacity in accordance with changes in suction pressure, and a biasing spring 418 that is adjusted by the excitation force of the solenoid coil 420.
Combined with the change in the biasing force, the temperature of the air blown from the evaporator can be controlled.

By the way, when performing capacity control as described above,
The control valve body 403 operates according to the behavior of the diaphragm 410 or the duty ratio applied to the solenoid coil 420. For this reason, the discharge pressure introduced into the control pressure chamber 200 through the high pressure introduction passage 96 fluctuates (pulsates), and vibrations occur in the control valve body 403 due to duty ratio control and the behavior of the diaphragm 410. Therefore, pressure hunting may occur in the control pressure chamber 200. Such pressure hunting induces hunting in capacity control, resulting in deterioration of driving feeling and cooling feeling.

In order to prevent this, in this embodiment, a check valve type regulating valve 600 is provided in the signal pressure passage 98.

That is, when discharge pressure is introduced into the control pressure chamber 200 from the high pressure introduction passage 96 through the signal pressure passage 98, the check valve body 605 is seated on the valve seat body 603 as shown in FIG. Since the four through holes 607 formed around the valve body 605 are closed, the discharge pressure is introduced only through the central throttle hole 606. Therefore, since the flow rate is regulated, pressure fluctuations are reduced, and pressure hunting in the control pressure chamber 200 is prevented.

If you want to quickly shift to the minimum capacity during acceleration, normally it takes time to switch if only the throttle hole 606 is conductive, but the check valve body 605 is in a state away from the valve seat body 603 and seated on the seat part 604. In this case, the four through holes 607 formed around the above are opened, and the control pressure chamber 200 and the signal pressure passage 98 are connected to the throttle holes 606 and 4.
All of the through holes 607 communicate with each other. Therefore, it is possible to quickly shift to the minimum capacity.

Therefore, when controlling the capacity of the swash plate compressor, it is possible to reduce the load fluctuation caused by pressure hunting in the control pressure chamber 200 during capacity control without taking time to shift to a low capacity, that is, without impairing acceleration performance. be able to.

Note that the results of experiments conducted by the present inventors will be appended.

Under the conditions of 27°C, 50%, rotation speed 11000 rpm, and duty ratio to solenoid coil 420 of 0.2,
In the absence of the pressure regulating valve 600, the pressure in the control pressure chamber 200 fluctuates by about 2 kg/c, and the compressor capacity also fluctuates by about 10% accordingly.

On the other hand, when the check valve type regulating valve 600 of the embodiment is installed, the pressure fluctuation in the control pressure chamber 200 is approximately 0. 8.
kg/a, and the fluctuation in compressor capacity was also reduced to about 3%.

Note that the present invention is not limited to the above embodiments,
For example, as shown in another embodiment in FIG. 6, the regulating valve 600 may be equipped with a spring member 610 that presses and biases the check valve body 605.

Furthermore, the four through holes 607 formed around the check valve body 605 are not limited to four as long as the flow path area is ensured, but one or more may be used, and the shape of the holes may be Various shapes such as circular and oval shapes are possible.

[Effects of the Invention] As explained above, the compressor of the present invention continuously and variably controls the compressor discharge capacity by the displacement of the spool, and also controls the amount of movement of the spool by the control valve. In addition to outputting a signal pressure based on fluctuations in the suction side pressure of the compressor, a solenoid is loaded on this control valve, and the excitation force of the solenoid also adjusts the urging force applied to the control valve body. Therefore, the discharge capacity of the compressor can be controlled so that the pressure on the suction side of the compressor is always constant, and the evaporation temperature of the evaporator of the refrigeration cycle can be kept constant. The compressor suction pressure, which is to be kept at a constant value, can be controlled. Therefore, in combination with the suction side pressure holding function described above, the evaporation temperature of the evaporator can be continuously and variably controlled.

Moreover, since the present invention provides a check valve type regulating valve in the signal pressure passage, when controlling the capacity of the swash plate compressor, it does not take time to shift to a low capacity, that is, without impairing acceleration performance.
It is possible to reduce load fluctuations caused by pressure hunting in the control pressure chamber during capacity control.

[Brief explanation of the drawing]

1 to 5 show an embodiment of the compressor of the present invention, FIG. 1 is a sectional view, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, and FIG. FIG. 4 is a configuration diagram of a check valve type regulating valve, FIG. 5 is a cross-sectional view of a check valve body, and FIG. 6 is a cross-sectional view showing another embodiment of the present invention. FIG. 2 is a configuration diagram of the check valve type regulating valve shown in FIG. 1...Shaft, 5.6...Housing, 7...
Piston, 10... Swash plate, 30... Spool, 96
...High pressure introduction passage, 97...Low pressure introduction passage, 98.
...Signal pressure passage, 200...Control pressure chamber, 400...
Control valve, 403... Control valve body, 410... Diaphragm, 412... Slide member, 416... Plunger, 420... Solenoid coil, 500... Control circuit. 600... Check valve type: A valve regulator, 603... Valve seat body, 605... Check valve body, 606... Throttle hole,
607...Through hole. ■Second

Claims (1)

[Claims] A cylinder block having a cylinder chamber inside, a shaft rotatably supported within the cylinder block, and a swash plate pivotally connected to the shaft and rotating integrally with the shaft. and a piston that is slidably disposed within the cylinder chamber and reciprocates within the cylinder chamber in response to the rocking motion of the swash plate, and between both ends of the piston and the inner surface of the cylinder chamber. a working chamber for suctioning, compressing, and discharging fluid; a supporting part disposed coaxially with the shaft and swingably supporting the center point of the swash plate; and a supporting part that supports the shaft. a spool that is displaceable in the axial direction of the shaft; a control pressure chamber that is formed in a portion of the spool on the opposite side of the support portion and that displaces the spool in the axial direction of the shaft in accordance with internal pressure; a control valve that controls signal pressure supplied to the chamber, the control valve having a low pressure introduction passage communicating with a low pressure section of the compressor, a high pressure introduction passage communicating with a high pressure section of the compressor, and the control valve a control valve body that adjusts pressure between a signal pressure passage communicating with a pressure chamber, a low pressure introduced via the low pressure introduction passage and a high pressure introduced via the high pressure introduction passage; and the compressor. a diaphragm that fluctuates according to the displacement of the low-pressure side pressure; a connecting portion that transmits the displacement of the diaphragm to the control valve body; a solenoid that changes the biasing force applied to the diaphragm in accordance with the signal pressure passage, and a check valve type that is provided in the signal pressure passage and performs a throttling action when the discharge pressure from the high pressure introduction passage is guided to the control pressure chamber through the signal pressure passage. A variable capacity swash plate compressor characterized by having a regulating valve.