JP2006177210A - Control valve for variable displacement compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control valve for a variable displacement compressor reducing the minimum operation transition time by increasing coolant flow rate by a simple structure and capable of being operated without requiring large solenoid force. <P>SOLUTION: In the control valve for the variable displacement compressor, force in a valve open direction by crank pressure Pc applied on a valve element 17 is canceled by force in a valve close direction by crank pressure Pc applied on a piston rod 18 by making section area of a section area of a valve hole 15 equal to section area of an end part of the piston rod 18 in an opposite side of the valve element. Since the valve element 17 is not influenced by crank pressure Pc via the valve hole 15, size of an inside of the valve hole 15 can be enlarged in a range of size of the piston rod 18 and the minimum operation transition time can be reduced by increasing flow rate of coolant flowing in the valve hole 15. Also, it is not necessary to increase solenoid force opposing to crank pressure Pc. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a control valve for a variable capacity compressor, and more particularly to a control valve for a variable capacity compressor for controlling a discharge capacity of a variable capacity compressor constituting a refrigeration cycle of an automotive air conditioner.

  Since the compressor used for compressing the refrigerant in the refrigeration cycle of the air conditioner for automobiles uses the engine as a drive source, the rotational speed control cannot be performed. Therefore, in order to obtain an appropriate cooling capacity without being restricted by the engine speed, a variable capacity compressor capable of changing the compression capacity of the refrigerant is used.

  In such a variable capacity compressor, a compression piston is connected to a swing plate attached to a shaft that is rotationally driven by an engine, and the stroke of the compression piston is changed by changing the angle of the swing plate. The amount of refrigerant discharged is changed.

  The angle of the swing plate is continuously increased by introducing a part of the compressed refrigerant into the sealed crank chamber, changing the pressure of the introduced refrigerant, and changing the balance of pressure applied to both sides of the compression piston. Is changing.

  The pressure in the crank chamber is adjusted by, for example, providing a control valve between the discharge chamber and the crank chamber of the variable capacity compressor and changing the flow rate of the refrigerant introduced from the discharge chamber into the crank chamber. At this time, an orifice is provided between the crank chamber and the suction chamber, and a path through which the refrigerant flows from the discharge chamber to the suction chamber is formed. The control valve includes, for example, a valve body capable of opening and closing a valve hole that is in contact with and separated from a valve hole that forms a refrigerant passage that communicates the discharge chamber and the crank chamber. And the flow rate of the refrigerant | coolant which flows from the discharge chamber side to the suction chamber side is adjusted by controlling the lift amount from the valve hole of this valve body (for example, refer patent document 1).

  More specifically, this control valve has a piston whose valve body is disposed on the downstream side of the valve hole (that is, on the crank chamber side) and has a diameter substantially the same as that of the valve hole on the side opposite to the valve hole of the valve body. Provide a rod. The piston rod is configured to receive suction pressure (Ps) and solenoid force in the valve closing direction on the end surface opposite to the valve body. The control valve communicates with the crank chamber of the variable capacity compressor a space provided with the valve body, that is, a space provided around the connecting portion between the valve body and the piston rod. As a result, the control valve communicates or closes the passage between the discharge chamber and the crank chamber so as to maintain the pressure difference (Pd−Ps) between the discharge pressure (Pd) and the suction pressure (Ps) at a predetermined value. By controlling, the predetermined value of the differential pressure can be set from the outside by the value of the current supplied to the solenoid. As a result, when the engine speed increases, the pressure (Pc) introduced into the crank chamber is increased to reduce the discharge capacity, and when the engine speed decreases, the orifice is made larger than the refrigerant flow rate introduced into the crank chamber. Thus, the flow rate released to the suction chamber is increased and the pressure (Pc) in the crank chamber is decreased to increase the discharge capacity, thereby keeping the discharge capacity of the variable capacity compressor constant.

At this time, the valve body receives the discharge pressure (Pd) from the upstream side through the valve hole, and receives the pressure (Pc) of the crank chamber on the opposite side to the valve hole. As described above, since the inner diameter of the valve hole and the outer shape of the piston rod are substantially the same, the pressure (Pc) in the crank chamber loaded on the valve body is cancelled. Therefore, the valve body of the control valve is purely controlled to open and close by the differential pressure (Pd−Ps) between the discharge pressure (Pd) and the suction pressure (Ps).
JP 2004-232533 A (FIG. 1 etc.)

  By the way, in such a control valve for a variable capacity compressor, it is necessary to maximize the flow rate of the refrigerant introduced into the crank chamber when attempting to operate the variable capacity compressor at the minimum operation in which the discharge capacity is minimized. However, if the size of the control valve is small at that time, the flow rate of the introduced refrigerant is small, so it takes time to shift to the minimum operation, the controllability deteriorates, or there is a case where it is not possible to shift to the minimum operation due to insufficient flow rate. . In addition, when the size of the valve hole is increased to increase the flow rate of the introduced refrigerant, the pressure receiving area of the valve body increases, so that a large solenoid force is required in the direction against the discharge pressure, which increases the size of the coil. There was a problem that this led to an increase in cost.

  The present invention has been made in view of the above points, and has a variable displacement compression that can be operated without requiring a large solenoid force while increasing the refrigerant flow rate to shorten the minimum operation transition time with a simple configuration. An object is to provide a control valve for a machine.

  In order to solve the above problem, the present invention controls the flow rate of the refrigerant introduced from the discharge chamber into the crank chamber so as to keep the differential pressure between the discharge pressure of the discharge chamber and the suction pressure of the suction chamber at a predetermined value. In a control valve for a variable capacity compressor that changes a discharge capacity of a refrigerant from a compressor, a body having a refrigerant passage formed therein and a refrigerant passage that communicates the discharge chamber and the crank chamber are formed in the body. A valve body that opens and closes the valve hole, and has a diameter-enlarged portion that can slide on the body at an intermediate portion of the shaft-shaped main body. A piston rod that is fixed to the valve body and receives the discharge pressure and receives the suction pressure on the other end side, a shaft that supports the piston rod in the axial direction, and corresponds to the differential pressure of the predetermined value Solenoid force A solenoid that is applied to the valve body through the shaft, and a pressure canceling structure that substantially cancels a crank pressure that is a pressure on the crank chamber side of the valve hole that is applied to the valve body, and the piston rod Senses the pressure difference between the discharge pressure and the suction pressure applied in the vicinity of the peripheral edge of the enlarged diameter portion, and operates in the opening / closing direction of the valve body, A valve is provided.

  In such a control valve for a variable capacity compressor, the crank pressure in the valve opening direction applied to the valve body that contacts and separates from the valve hole is substantially canceled by the pressure canceling structure. Then, a differential pressure between the discharge pressure and the suction pressure is applied to the piston rod substantially only at the peripheral edge. As a result, since the valve body is not substantially affected by the crank pressure via the valve hole, the size of the valve hole can be freely changed within a range in which the pressure canceling structure functions.

  According to the control valve for a variable capacity compressor of the present invention, the pressure canceling structure can eliminate the influence of the crank pressure via the valve hole, so that the pressure canceling structure functions the size of the valve hole. It can be increased within the range of the size of the piston rod. In other words, the simple configuration of canceling the pressure can increase the valve hole through which the refrigerant flowing from the discharge chamber side to the crank chamber side passes. As a result, the flow rate of the refrigerant flowing through the valve hole is increased and the minimum operation shift is made. Time can be shortened. Also, even if the valve hole is enlarged, the crank pressure applied to the valve body is canceled, so there is no need to increase the solenoid force against the crank pressure, and the solenoid and thus the control valve for the variable capacity compressor is large. Can be prevented.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, for the sake of convenience, the positional relationship between the structures may be expressed as upper and lower with reference to the illustrated state.
[First Embodiment]
FIG. 1 is a cross-sectional view illustrating a configuration of a variable displacement compressor control valve according to a first embodiment.

  The variable displacement compressor control valve 1 includes a valve component 2 that opens and closes a refrigerant flow path for allowing a part of refrigerant discharged from a variable displacement compressor (not shown) to flow into the crank chamber, and a valve of the valve component 2. And a solenoid 3 for controlling the flow rate of the refrigerant passing therethrough by adjusting the valve opening amount of the unit.

  The valve component 2 is provided with a port 12 on the side of the body 11 for receiving the discharge pressure Pd in communication with the discharge chamber of the variable capacity compressor. The port 12 communicates internally with a port 13 opened at the top of the body 11. The port 13 communicates with a crank chamber of the variable capacity compressor and derives a controlled pressure (referred to as “crank pressure”) Pc in the crank chamber.

  A cylindrical valve seat forming member 14 is fitted in the refrigerant passage communicating the port 12 and the port 13, a valve hole 15 is formed by the internal passage, and the valve seat is formed by the inner peripheral edge of the discharge chamber side end. 16 is formed.

  Further, the valve body 17 is disposed so as to be able to contact and separate in the axial direction so as to face the valve seat 16 from the side where the discharge pressure Pd is introduced. The valve body 17 is coaxially integrated with a long piston rod 18 extending in the axial direction. The piston rod 18 is slidably inserted into the first guide hole 19 and the second guide hole 20 formed in the body 11 in the vicinity of the end in the longitudinal direction and the end opposite to the valve body 17. The distal end of the end opposite to the valve body 17 is supported by a long shaft 21 arranged coaxially so as to be movable back and forth in the axial direction. A discharge pressure Pd from the discharge chamber is introduced into a small diameter portion that is a connection portion between the piston rod 18 and the valve body 17. The valve body 17 is urged in the valve opening direction by a spring 22 interposed between the valve seat forming member 14 and the small diameter portion of the piston rod 18.

  Further, a port 23 that is connected to the suction chamber of the variable capacity compressor and receives the suction pressure Ps is formed slightly below the center of the body 11, and is sucked between the first guide hole 19 and the second guide hole 20. Pressure Ps is introduced.

  Further, an opening hole 24 having a predetermined depth is formed in the center of the lower end of the body 11, and a contact portion between the piston rod 18 and the shaft 21 is arranged. The body 11 is provided with a crank pressure introduction path 25 that penetrates the vicinity of the outer periphery of the body 11 in the vertical direction and communicates with the opening hole 24. The crank pressure Pc is provided in the opening hole 24 through the crank pressure introduction path 25. Can be introduced.

  On the other hand, the solenoid 3 includes a core 32 fixed in the case 31, a plunger 33 for moving the valve element 17 back and forth via the shaft 21 to open and close the valve component 2, and a core supplied by an externally supplied current. 32 and an electromagnetic coil 34 for generating a magnetic circuit including a plunger 33.

  The core 32 is provided with a threaded portion at the upper end thereof, and the threaded portion is fixed to the body 11 by being screwed into a threaded portion provided in the opening hole 24 of the body 11. The core 32 is provided with an insertion hole that passes through the center in the axial direction and passes through the upper half of the shaft 21. The upper end opening of the core 32 slidably supports the upper end of the shaft 21. A cylindrical guide member 35 is inserted.

  The bottom half of the bottomed sleeve 36 whose bottom end is closed is extrapolated to the bottom half of the core 32. In the bottomed sleeve 36, the plunger 33 is integrated with the shaft 21. It is supported so that it can move forward and backward. The bottomed sleeve 36 is fitted at its upper end into a groove portion provided around the central portion of the core 32. Further, a seal member 37 having a gourd-shaped cross section is disposed between the bottomed sleeve 36 and the core 32 to keep the inside of the bottomed sleeve 36 airtight.

  A bearing member 38 is disposed at the lower end of the bottomed sleeve 36 and supports the lower end of the shaft 21 so as to be slidable. A plunger 33 is fitted to the lower portion of the shaft 21 in the longitudinal direction. The plunger 33 has a spring receiving member 39 inserted into its upper end opening, and is urged downward by a spring 40 interposed between the core 32 and the spring receiving member 39, while It is interposed therebetween and is biased upward by a spring 41. And the spring load which the spring 40 provides to the plunger 33 can be adjusted now by changing the insertion amount to the plunger 33 of the spring receiving member 39. FIG. The coil 34 is disposed on the outer periphery of the bottomed sleeve 36, and a harness 42 for supplying power to the coil 34 is led out to the outside.

Next, the pressure cancellation structure of the present embodiment will be described. FIG. 2 is a partially enlarged view showing the configuration around the piston rod in FIG.
The piston rod 18 has a diameter-enlarged portion 51 having a larger cross section than both ends of the middle portion of the cylindrical main body. The enlarged diameter portion 51 is slidably inserted into the first guide hole 19. On the other hand, the portion below the enlarged diameter portion 51 of the piston rod 18 extends downward with the same cross-sectional area so that the pressure receiving area thereof is equal to the cross-sectional area A of the valve hole 15, that is, the pressure receiving area of the valve body 17. It is configured. For this reason, the force in the valve opening direction due to the crank pressure Pc applied to the valve body 17 through the valve hole 15 is canceled by the force in the valve closing direction due to the crank pressure Pc applied to the lower end portion of the piston rod 18. . For this reason, as shown in the figure, the substantial pressure receiving area of the piston rod 18 is an area C obtained by subtracting the cross-sectional area A of the lower end portion from the cross-sectional area B of the enlarged diameter portion 51. That is, the piston rod 18 senses a differential pressure between the discharge pressure Pd and the suction pressure Ps applied to the area C in the vicinity of the peripheral edge of the enlarged diameter portion 51 and operates in the opening / closing direction of the valve body 17. become.

  Further, a flexible film-like seal member 52 is provided so as to bridge the upper end of the enlarged diameter portion 51 and the body 11, and the high-pressure refrigerant in the port 12 allows the enlarged diameter portion 51 and the first guide hole 19. Leakage to the low pressure port 23 side. In addition, this sealing member 52 can be comprised, for example from metal films, such as resin films, such as a polyimide film, and a copper plate.

  Returning to FIG. 1, in the variable displacement compressor control valve 1 having the above-described configuration, the spring load by the spring 22 and the spring 40 that applies the biasing force in the valve opening direction to the valve body 17 is the biasing force in the valve closing direction. Is set to be larger than the spring load of the spring 41 for imparting. For this reason, when the solenoid 3 is not energized, the valve body 17 is separated from the valve seat 16 and the valve portion is held in a fully opened state. At this time, the high-pressure refrigerant having the discharge pressure Pd introduced from the discharge chamber of the variable capacity compressor to the port 12 passes through the valve portion in the fully open state and flows from the port 13 to the crank chamber. Therefore, the variable capacity compressor is operated with the minimum discharge capacity because the crank chamber pressure Pc is close to the discharge pressure Pd.

  On the other hand, the current value supplied to the solenoid 3 becomes maximum when the automotive air conditioner is started or when the cooling load is maximum. At this time, since the plunger 33 is attracted to the core 32 with the maximum suction force, the piston rod 18 is closed by the shaft 21 fixed to the plunger 33 against the urging force of the springs 22 and 40. The valve body 17 is seated on the valve seat 16 and the valve portion is fully closed. At this time, since the high-pressure refrigerant having the discharge pressure Pd introduced into the port 12 is blocked by the fully closed valve portion, the variable capacity compressor has the crank chamber pressure Pc close to the suction pressure Ps. The operation with the maximum discharge capacity is performed.

  Here, when the current value supplied to the solenoid 3 is set to a predetermined value, the valve body 17 is biased in the valve opening direction and the spring load of the springs 22 and 40 biased in the valve opening direction. The spring load of the spring 41 being urged, the load of the solenoid 3 biased in the valve closing direction, the force due to the discharge pressure Pd receiving pressure in the valve opening direction, and the force due to the suction pressure Ps receiving pressure in the valve closing direction Stops at the balanced valve lift position. As described above, the differential pressure between the discharge pressure Pd and the suction pressure Ps applied to the peripheral edge of the piston rod 18 is applied to the valve body 17.

  In this balanced state, if the rotational speed of the variable capacity compressor is increased by increasing the engine speed and the discharge capacity is increased, the discharge pressure Pd is increased and the suction pressure Ps is decreased. (Pd−Ps) increases, and a force in the valve opening direction acts on the valve body 17 and the piston rod 18, and the valve body 17 further increases the flow rate of the refrigerant flowing from the discharge chamber to the crank chamber. It will be. As a result, the crank chamber pressure Pc increases, and the variable displacement compressor operates in a direction to decrease its discharge capacity, and the differential pressure (Pd−Ps) is controlled to be a predetermined value set by the solenoid 3. Is done. When the engine speed decreases, the reverse operation is performed, and the variable capacity compressor is controlled so that the differential pressure (Pd−Ps) becomes a predetermined value set by the solenoid 3.

  As described above, in the variable displacement compressor control valve 1 of the present embodiment, the sectional area of the valve hole 15 and the sectional area of the piston rod 18 opposite to the valve body are equal. Thus, the force in the valve opening direction due to the crank pressure Pc applied to the valve body 17 is canceled by the force in the valve closing direction due to the crank pressure Pc applied to the piston rod 18. For this reason, the valve body 17 is not affected by the crank pressure Pc through the valve hole 15. By adopting such a cancel structure, the size of the valve hole 15 can be increased within the range of the size of the piston rod 18. As a result, the minimum operation transition time can be shortened by increasing the flow rate of the refrigerant flowing through the valve hole 15. Even if the valve hole 15 is enlarged, the crank pressure Pc applied to the valve element 17 is canceled, so there is no need to increase the solenoid force against the crank pressure Pc, and the solenoid 3 and thus the variable capacity compressor. It is possible to prevent the control valve 1 from becoming large.

  In the present embodiment, the structure in which the opposite side to the valve body 17 of the combined body in which the valve body 17 and the piston rod 18 are integrally formed is supported by the shaft 21, but at least a part of the shaft 21 is shown. May be inserted into the combined body. That is, a hole that opens downward along the axis is provided in the combined body of the valve body and the piston rod, and a part of the shaft is inserted into the hole to support the combined body. Good. For example, the combined body may be formed into a cup shape by deep drawing a plate material with a press.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. The control valve for a variable displacement compressor according to the present embodiment is the same as the configuration shown in the first embodiment, except that the structure for introducing the crank pressure is different from the piston rod valve body. . For this reason, about the component similar to the said 1st Embodiment, the same code | symbol is attached | subjected etc., and the description is abbreviate | omitted suitably. FIG. 3 is a cross-sectional view showing the configuration of the control valve for a variable capacity compressor according to the present embodiment.

  In this variable displacement compressor control valve 201, there is no crank pressure introduction passage that penetrates the body 211 of the valve component 202, and the integrated valve body 217 and piston rod 218 penetrate in the axial direction. Thus, a crank pressure introduction path 225 is formed. The crank pressure introduction path 225 communicates with the opening hole 24 at the center of the lower end of the body 211.

  By comprising in this way, it becomes unnecessary to provide a through-hole in the body 211, Complicating manufacture and the enlargement of the body 211 can be prevented. It can be said that such a configuration in which the crank pressure introduction path 225 is provided has become easy to realize because the valve hole 15 is enlarged and the pressure receiving area of the valve body 217 can be made relatively large.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. The control valve for a variable capacity compressor according to the present embodiment is different from the first embodiment in that it has a structure for introducing suction pressure on the opposite side of the piston rod from the valve body. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted as appropriate. FIG. 4 is a cross-sectional view showing a configuration of a control valve for a variable capacity compressor according to the present embodiment.

  In this variable displacement compressor control valve 301, the body 311 of the valve component 302 is not provided with a crank pressure introduction path, and the suction pressure Ps is introduced to the opposite side of the piston rod 318 from the valve body 317. That is, the port 23 for introducing the suction pressure Ps communicates with the opening hole 324 at the center of the lower end of the body 311. The guide member 335 provided at the upper end opening of the core 32 is formed with a refrigerant passage 336 penetrating the peripheral edge thereof in the axial direction, and the suction pressure Ps introduced into the port 23 causes the refrigerant passage 336 to pass through. It is introduced into the bottomed sleeve 36 through.

  Further, the valve body 317 has a groove portion 353 formed between the enlarged diameter portion 351 and the lower end portion 352 (the end portion opposite to the valve body 317). A spring 322 for biasing the piston rod 318 in the valve opening direction is interposed between the body 311 and the groove portion 353. The spring 322 replaces the spring 22 of FIG. 1 described in the first embodiment, and the spring 22 is disposed in a high pressure region where the discharge pressure Pd is introduced. It is arranged in a low pressure region where Ps is introduced. The length of the lower end portion 352 in the axial direction is short, and the pressure receiving area thereof is equal to the cross-sectional area of the valve hole 15, that is, the pressure receiving area of the valve body 317.

  Therefore, the force in the valve opening direction due to the crank pressure Pc applied to the valve body 317 is canceled out by the force in the valve closing direction due to the suction pressure Ps applied to the lower end portion 352 of the piston rod 318. In this case, since the crank pressure Pc is usually higher than the suction pressure Ps, it is not completely cancelled. However, the pressure difference is substantially smaller than the pressure difference between the discharge pressure Pd and the suction pressure Ps. Can be considered canceled.

It is sectional drawing which shows the structure of the control valve for variable capacity compressors which concerns on 1st Embodiment. It is the elements on larger scale showing the structure of the piston rod periphery in FIG. It is sectional drawing which shows the structure of the control valve for variable capacity compressors which concerns on 2nd Embodiment. It is sectional drawing which shows the structure of the control valve for variable capacity compressors which concerns on 3rd Embodiment.

Explanation of symbols

1, 201, 301 Control valve for variable capacity compressor 2, 202, 302 Valve component 3 Solenoid 11, 211, 311 Body 14 Valve seat forming member 15 Valve hole 16 Valve seat 17, 217, 317 Valve body 18, 218, 318 Piston rod 19 First guide hole 20 Second guide hole 21 Shaft 25, 225 Crank pressure introduction path 35 Guide member 36 Bottomed sleeve 51, 351 Expanded portion 52 Seal member 352 Lower end portion 353 Groove portion

Claims (7)

The refrigerant discharge capacity from the variable capacity compressor is changed by controlling the flow rate of refrigerant introduced from the discharge chamber to the crank chamber so that the differential pressure between the discharge pressure of the discharge chamber and the suction pressure of the suction chamber is maintained at a predetermined value. In the control valve for variable capacity compressor,
A body having a refrigerant passage formed therein;
In the body, a valve body that is disposed so as to contact and separate from the discharge chamber side to a valve hole that forms a refrigerant passage that communicates the discharge chamber and the crank chamber, and opens and closes the valve hole;
A piston rod having an enlarged diameter portion slidable on the body at an intermediate portion of the shaft-shaped main body, one end side being fixed to the valve body and receiving the discharge pressure, and the other end side receiving the suction pressure When,
A shaft that supports the piston rod in the axial direction;
A solenoid that applies a solenoid force corresponding to the differential pressure of the predetermined value to the valve body via the shaft;
A pressure canceling structure that substantially cancels the crank pressure, which is the pressure on the crank chamber side of the valve hole applied to the valve body;
With
The variable displacement compression characterized in that the piston rod senses a differential pressure between the discharge pressure and the suction pressure applied in the vicinity of a peripheral portion of the enlarged diameter portion, and operates in the opening / closing direction of the valve body. Control valve for machine.   The control valve for a variable capacity compressor according to claim 1, wherein the piston rod extends in the same axial direction as the valve body and is formed integrally with the valve body. The piston rod includes a discharge pressure receiving portion that receives the discharge pressure at an end portion of the enlarged diameter portion on the valve body side, and an intake pressure at an end portion of the enlarged diameter portion opposite to the valve body. A suction pressure receiving portion for receiving pressure, and a crank pressure receiving portion for receiving the crank pressure at an end opposite to the valve body,
3. The variable capacity compressor according to claim 2, wherein the pressure canceling structure is realized by forming an inner diameter of the valve hole and an outer diameter of the crank pressure receiving portion to be substantially the same. Control valve.   4. The control valve for a variable capacity compressor according to claim 3, wherein a crank pressure introduction path for introducing the crank pressure on the crank chamber side to the crank pressure receiving portion side is provided in the body.   4. The piston rod has a through-hole extending in the axial direction, and is configured to introduce a crank pressure on the crank chamber side of the valve body to the crank pressure receiving portion side. The control valve for a variable displacement compressor as described.   A flexible seal member is provided between the piston rod and the body to seal the gap between the enlarged diameter portion and the body, thereby preventing the refrigerant having the discharge pressure from flowing into the gap. The control valve for a variable capacity compressor according to claim 1, wherein The piston rod includes a discharge pressure receiving portion that receives the discharge pressure at an end portion of the enlarged diameter portion on the valve body side, and an intake pressure at an end portion of the enlarged diameter portion opposite to the valve body. A first suction pressure receiving portion that receives pressure, and a second suction pressure receiving portion that receives the suction pressure at an end opposite to the valve body,
3. The variable capacity according to claim 2, wherein the pressure canceling structure is realized by forming the inner diameter of the valve hole and the outer diameter of the second suction pressure receiving portion to be substantially the same. Control valve for compressor.

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