JP4504243B2 - Control valve for variable displacement compressor - Google Patents

Description

  The present invention relates to a control valve for a variable capacity compressor used in a car air conditioner and the like, and in particular, a variable capacity that can be applied to a large capacity compressor while sharing parts with other control valves. The present invention relates to a control valve for a type compressor.

  In general, a control valve for a variable displacement compressor used in a car air conditioner or the like introduces a refrigerant having a discharge pressure Pd from a compressor (discharge chamber) in order to adjust a pressure Pc in a crank chamber of the compressor. The refrigerant having the discharge pressure Pd is squeezed out and led to the crank chamber, and the derivation amount (throttle amount) to the crank chamber is controlled according to the suction pressure Ps of the compressor. As seen in Patent Document 1 and the like, various proposals or practical applications using electromagnetic actuators (solenoids) have been made.

  A conventional example of such a variable displacement compressor control valve is shown in FIG. The illustrated control valve 5 includes a valve rod 15 ′ having a valve body portion 15 a and a valve chamber 21 provided with a valve seat (valve port) 22 to which the valve body portion 15 a comes in contact with and away from the valve body 15 a. A plurality of discharge pressure refrigerant inlets 25 with a filter 25A for introducing a refrigerant having a discharge pressure Pd from the compressor are provided on the outer peripheral portion (upstream side of the valve seat 22), and below (downstream side) of the valve seat 22 A valve body 20 ′ provided with a refrigerant outlet 26 communicating with the crank chamber of the compressor, and an electromagnetic actuator 30 are provided.

  The electromagnetic actuator 30 includes a coil 32 having a connector portion 31 for energization excitation, a cylindrical stator 33 disposed on the inner peripheral side of the coil 32, and a concave section that is press-fitted and fixed to the inner periphery of the lower end portion of the stator 33. Pipe-shaped suction element 34, pipe 35 with flange 35a whose upper end is joined to the outer periphery (step part) of the lower end of stator 33 by TIG welding, and the upper and lower sides of pipe 35 below the suction element 34 A plunger 37 slidably disposed in the direction and a cylindrical housing 60 with a bottomed hole disposed so as to cover the outer periphery of the coil 32 are provided.

  Further, an adjusting screw 65 having a hexagonal hole is screwed onto the stator 33, and a suction pressure Ps of the compressor is interposed between the adjusting screw 65 and the suction element 34 on the inner peripheral side of the stator 33. Is formed in the pressure sensing chamber 45. The pressure sensing chamber 45 includes a bellows 41, a reverse convex upper stopper 42, a reverse concave lower stopper 43, and a compression coil. A bellows body 40 comprising a spring 44 is disposed, and further, a compression coil that urges the bellows body 40 and the suction element 34 in a direction in which the bellows body 40 contracts (a direction in which the bellows body 40 is compressed toward the adjustment screw 65). A spring 46 is disposed. Also, a stepped operating rod 14 that passes through the suction element 34 is disposed between the lower stopper 43 (reverse concave part thereof) of the bellows body 40 and the plunger 37 (recessed part 37c thereof). A valve-opening spring 47 made up of a compression coil spring that biases the valve rod 15 ′ downward (in the valve-opening direction) via the plunger 37 is disposed between the pipe 34 and the plunger 37 (the concave portion 37 b). .

  On the other hand, a convex stopper portion 28 for restricting the lowest position of the plunger 37 protrudes from the upper center of the valve body 20 ′, and a central portion above the valve chamber including the convex stopper portion 28 is provided. A guide hole 19 into which the valve stem 15 ′ is slidably fitted is formed. In addition, a suction pressure refrigerant introduction chamber 23 into which a refrigerant having a suction pressure of the compressor is introduced is formed between the plunger 37 and the upper outer periphery (outer periphery of the convex stopper portion 28) of the valve body 20 ′. A plurality of suction pressure refrigerant introduction ports 27 are formed on the outer peripheral side, and the refrigerant having the suction pressure Ps introduced from the suction pressure refrigerant introduction port 27 into the suction pressure refrigerant introduction chamber 23 is formed on the outer periphery of the plunger 37. Are introduced into the pressure-sensitive chamber 45 through the longitudinal grooves 37a, 37a,..., The communication hole 37d formed in the central portion, the communication hole 39 formed in the suction element 34, and the like.

  A valve closing spring 48 made of a conical compression coil spring for biasing the valve rod 15 ′ upward is disposed at the lower portion (refrigerant outlet 26) of the valve body 20 ′. Due to this urging force, the upper end portion of the valve stem 15 ′ is always in pressure contact with the plunger 37 (the communication hole 37d portion thereof).

  Further, a lower end flange 35a of the pipe 35 is placed on the upper end of the valve body 20 ′ via an O-ring 57, and a flange 56a is provided between the flange 35a and the coil 32. A short cylindrical pipe holder 56 is interposed, and the flange portions 35a and 56a are fastened and fixed together by an upper end outer periphery caulking portion 29 of the valve body 20 ′. Further, the bottom portion 61 with a hole of the housing 60 is press-fitted and fixed to the upper end portion of the pipe holder 56, and the upper end portion 62 of the housing 60 is caulked and fixed on the flange-shaped portion 31 c of the connector portion 31. An O-ring 66 is interposed between the connector part 31 and the coil 32. A concave portion 31a is formed at the lower center of the connector portion 31. The concave portion 31a is formed with a convex portion 31b fitted into the hexagonal hole of the adjusting screw 65. The stator 33 and the adjusting screw are formed in the concave portion 31a. The upper part of 65 is inserted.

In the control valve 5 having such a configuration, when the solenoid portion including the coil 32, the stator 33, and the attractor 34 is energized and energized, the plunger 37 is attracted to the attractor 34. 'Is moved upward (in the valve closing direction) by the urging force of the valve closing spring 48. On the other hand, the refrigerant having the suction pressure Ps introduced from the compressor to the suction pressure introduction port 27 communicates with the longitudinal grooves 37a, 37a,... Formed in the outer periphery of the plunger 37 from the introduction chamber 23 and the suction element 39. The bellows body 40 (inside the vacuum pressure) is expanded and contracted according to the pressure in the pressure sensitive chamber 45 (suction pressure Ps), and contracts and decreases when the suction pressure Ps is high. The displacement is transmitted to the valve stem 15 ′ via the actuating rod 14 and the plunger 37, whereby the valve opening degree (effective passage cross-sectional area between the valve seat 22 and the valve body portion 15a) is increased. Adjusted. That is, the opening degree of the valve includes the attraction force of the plunger 37 by the solenoid portion including the coil 32, the stator 33 and the attraction element 34, the urging force of the bellows body 40, the urging force by the valve opening spring 47 and the valve closing spring 48, According to the valve opening, the amount of discharge pressure Pd introduced from the discharge pressure refrigerant introduction port 25 into the valve chamber 21 to the refrigerant outlet 26 side, that is, the amount (throttle amount) to the crank chamber is adjusted. Thus, the pressure (supply pressure) Pc in the crank chamber is controlled.
JP-A-2002-303262

  By the way, the inventors of the present application can adapt to a large-capacity compressor while sharing parts with other control valves such as the control valve 5 for the variable displacement compressor described above for cost reduction and the like. We are developing a control valve. However, in order to adapt to a large capacity compressor, there are the following problems to be solved.

  That is, in order to adapt to a large capacity compressor, it is necessary to enlarge the valve port 22 and increase the flow rate of refrigerant supplied from the refrigerant outlet 26 to the compressor crank chamber. The pressure on the refrigerant outlet 26 side (supply pressure Pc to the crank chamber) acting on 15 ′ (valve body portion 15a) increases. In the conventional control valve 5, the differential pressure (Pc−Ps) between the supply pressure Pc and the suction pressure Ps (acting on the upper end surface of the valve rod 15 ′) is slight and is negligible for control. However, if the flow rate of the refrigerant is increased by increasing the valve port 22 so as to be adapted to a large capacity compressor, the influence caused by the differential pressure between the supply pressure Pc and the suction pressure Ps increases, and the electromagnetic type If the specifications and the like of the actuator 30 and the pressure sensitive response member 40 are the same (shared), the valve rod 15 ′ (valve body portion 15a) is pushed upward (closed direction) by this differential pressure, and control is performed. Adversely affect.

  In the control valve 5 as described above, the pressure of the refrigerant introduced into the valve chamber 21 from the discharge pressure refrigerant inlet 25 (discharge pressure Pd) is the pressure of the refrigerant in the suction pressure refrigerant introduction chamber 23 (intake pressure). Ps), a part of the refrigerant introduced into the valve chamber 21 leaks into the suction pressure refrigerant introduction chamber 23 through the sliding surface of the valve rod 15 'and the guide hole 19, but this Pd → Ps leakage. As the amount increases, the control is adversely affected. Therefore, it is desirable to reduce the Pd → Ps leakage amount as much as possible.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a variable capacity compressor that can be applied to a large capacity compressor while sharing parts with other control valves. It is to provide a control valve.

  In order to achieve the above object, a control valve for a variable displacement compressor according to the present invention basically includes a valve stem having a valve body and a guide hole into which the valve stem is slidably inserted. And a valve chamber provided with a valve port for contacting and separating the valve body, and provided with a discharge pressure refrigerant inlet for introducing a refrigerant of discharge pressure from the compressor upstream from the valve port, A valve body provided with a refrigerant outlet communicating with the crank chamber of the compressor downstream from the valve port; an electromagnetic actuator for driving the valve rod in the valve port opening / closing direction; and a suction pressure of the compressor And a pressure-sensitive response member that drives the valve stem in the valve opening / closing direction in response to the pressure.

  A small-diameter hole is provided in the upper portion of the guide hole, and a small-diameter portion that is slidably inserted into the small-diameter hole is provided in the upper portion of the valve rod. Pressure equalization for introducing pressure into a pressure equalization pressure introducing chamber formed between a large diameter hole portion below the small diameter hole portion in the guide hole and a large diameter portion below the small diameter portion in the valve rod. It is characterized in that a hole is formed.

  In a more specific preferred embodiment, a valve stem having a valve body portion, a guide hole into which the valve stem is slidably inserted, and a valve chamber provided with a valve port for contacting and separating the valve body portion are provided. A discharge pressure refrigerant inlet for introducing refrigerant at a discharge pressure from the compressor upstream from the valve port, and a refrigerant outlet communicating with the crank chamber of the compressor downstream from the valve port. A provided valve body, a coil, a cylindrical stator disposed on the inner peripheral side of the coil, a suction element fixed to the stator, and a sliding part disposed vertically below the suction element An electromagnetic actuator having a plunger formed thereon, a pressure sensing chamber formed above the suction element on the inner peripheral side of the stator and introduced with suction pressure from the compressor, and disposed in the pressure sensing chamber A pressure-sensitive response member, and a pressure-sensitive response member and the plunger. When the plunger is attracted to the suction element, the valve body portion is moved in the valve closing direction, and the operating rod is pushed downward by the pressure-sensitive response member. Accordingly, the valve body portion is moved in the valve opening direction, a small diameter hole portion is provided in the upper portion of the guide hole, and the small diameter hole portion is slidable in the upper portion of the valve rod. A small-diameter portion to be inserted is provided, and a refrigerant pressure at the refrigerant outlet is applied to the valve rod so that a large-diameter hole portion below the small-diameter hole portion in the guide hole and a lower-diameter portion of the valve rod are below the small-diameter portion. A pressure equalizing hole leading to a pressure equalizing pressure introducing chamber formed between the large diameter portion and the large diameter portion is formed.

  In a preferred embodiment, a ring-shaped groove is formed on the outer periphery of the portion of the valve stem that is in sliding contact with the large-diameter hole portion of the guide hole.

  In the control valve for a variable displacement compressor according to the present invention, the pressure on the refrigerant outlet side (supply pressure Pc to the crank chamber) acting on the valve body of the valve rod is passed through a pressure equalizing hole formed in the valve rod. Then, the pressure is introduced into the pressure equalizing pressure introduction chamber and acts in the direction of pushing down the valve rod, that is, in the direction of reducing (cancelling) the differential pressure between the supply pressure Pc and the suction pressure Ps. For this reason, even if the valve port is enlarged and the refrigerant flow rate is increased to adapt to a large-capacity compressor, the valve stem (valve part) is moved upward by the differential pressure between the supply pressure Pc and the suction pressure Ps ( (The closing direction) is not pushed up, and the control problem is solved. As a result, it is possible to provide a control valve that can be applied to a large-capacity compressor while sharing parts with other control valves.

  Further, a part of the refrigerant introduced into the valve chamber from the discharge pressure refrigerant inlet is led to the pressure equalizing pressure introducing chamber through the sliding contact surface of the valve rod and the guide hole, and from here through the pressure equalizing hole. To the refrigerant outlet. In other words, there is almost no leakage from the discharge pressure Pd to the suction pressure Ps in the conventional control valve, and the discharge pressure Pd goes to the supply pressure Pc side, so that the control is not adversely affected. Improvement and the like.

  Hereinafter, embodiments of a control valve for a variable displacement compressor of the present invention will be described with reference to the drawings.

  FIG. 1 is a longitudinal sectional view showing an embodiment of a control valve for a variable displacement compressor according to the present invention.

  A variable displacement compressor control valve 1 shown in FIG. 1 includes an electromagnetic actuator 30 and a pressure-sensitive responsive member (bellows main body) 40 in the conventional variable displacement compressor control valve 5 shown in FIG. In the following, the parts corresponding to the respective parts of the control valve 5 for the variable displacement compressor of the conventional example shown in FIG. Are given the same reference numerals, and differences will be described with emphasis.

  The illustrated control valve 1 is provided with a valve stem 15 (which will be described in detail later) having a cross-shaped or T-shaped valve body portion 15a, and a valve seat (valve port) 22 with which the valve body portion 15a contacts and separates. A valve chamber 21 is provided, and a plurality of discharge pressure refrigerant introduction ports 25 for introducing a refrigerant having a discharge pressure Pd from the compressor are provided on the outer peripheral portion (upstream side of the valve seat 22) of the valve chamber 21, and the valve A valve body 20 provided with a refrigerant outlet 26 communicating with a crank chamber of the compressor is provided below the seat 22 (downstream side), and an electromagnetic actuator 30.

  The electromagnetic actuator 30 includes an electromagnetic coil 32 having a connector portion 31 for energization excitation, a stepped cylindrical stator 33 disposed on the inner peripheral side of the coil 32, and press-fitted and fixed to the inner periphery of the lower end of the stator 33. A suction member 34 having a concave cross section, a plunger 37 disposed below the suction member 34 so as to be slidable in the vertical direction on the inner peripheral side of the guide pipe 35, and an inner periphery of the upper end portion of the lower end portion of the stator 33. A cylindrical guide pipe 35 for guiding the plunger 37, which is connected and fixed by brazing, a stepped cylindrical housing 60 disposed so as to cover the outer periphery of the coil 32, and an upper end portion of the valve body 20 And a short cylindrical holder 50 disposed between the coil 32 and the coil 32.

  The lower end portion of the pipe 35 is fitted into the inner periphery of the holder 50 and connected and fixed by brazing, and the lower small diameter portion 61 of the housing 60 is press-fitted into the outer periphery of the holder 50. An upper end portion 62 of the housing 60 is caulked and fixed near the upper end portion of the coil 32. At the lower part of the holder 50, there is provided a cylindrical portion 50a with a thin flange that is fitted on the outer periphery of the upper portion of the valve body 20, and the holder 50 is fixed to the valve body 20 by peeling and staking the cylindrical portion 50a with the thin flange. Has been.

  Further, an adjusting screw 65 having a hexagonal hole is screwed onto the stator 33, and a suction pressure Ps of the compressor is interposed between the adjusting screw 65 and the suction element 34 on the inner peripheral side of the stator 33. Is formed in the pressure sensing chamber 45. The pressure sensing chamber 45 includes a bellows 41, a reverse convex upper stopper 42, a reverse concave lower stopper 43, and a compression coil. A bellows body 40 comprising a spring 44 is disposed, and further, a compression coil that urges the bellows body 40 and the suction element 34 in a direction in which the bellows body 40 contracts (a direction in which the bellows body 40 is compressed toward the adjustment screw 65). A spring 46 is disposed. Also, a stepped operating rod 14 that passes through the suction element 34 is disposed between the lower stopper 43 (reverse concave part thereof) of the bellows body 40 and the plunger 37 (recessed part 37c thereof). A valve-opening spring 47 made of a compression coil spring that biases the valve rod 15 downward (in the valve-opening direction) via the plunger 37 is disposed between the valve 34 and the plunger 37 (the recess 37b).

  On the other hand, a convex stopper portion 28 for restricting the lowest position of the plunger 37 protrudes from the upper center of the valve body 20, and the central portion above the valve chamber including the convex stopper portion 28 includes: A guide hole 19 (described in detail later) into which the valve stem 15 is slidably fitted is formed. In addition, a suction pressure refrigerant introduction chamber 23 into which a refrigerant having a suction pressure Ps of the compressor is introduced is formed between the plunger 37 and the upper outer periphery (outer periphery of the convex stopper portion 28) of the valve body 20. A plurality of suction pressure refrigerant inlets 27 are formed on the outer peripheral side, and the suction pressure Ps introduced from the inlet 27 into the introduction chamber 23 is formed by vertical grooves 37 a, 37 a,. In addition to being introduced into the pressure sensing chamber 45 through a communication hole 37d formed in the portion, a communication hole 39 formed in the suction element 34, and the like, it also acts on the upper end surface of the valve rod 15.

  Further, in the refrigerant outlet 26 provided at the lowermost part of the valve body 20, a conical compression in which the valve rod 15 is urged upward and the upper end thereof is pressed against the plunger 37 (the communication hole 37 d portion thereof). A valve closing spring 48 made of a coil spring is disposed.

  And in the control valve 1 of this embodiment, in order to adapt to a large capacity compressor, the diameters of the valve port 22, the valve stem 15, and the guide hole 10 are the same as those of the control valve 5 shown in FIG. As shown in FIG. 2 (partially enlarged view) in addition to FIG. 1, a small-diameter hole portion 19 b is provided in the upper portion of the guide hole 19, and the valve stem is 15 is provided with a small-diameter portion 15b that is slidably fitted into the small-diameter hole portion 19b. The valve rod 15 is supplied with the refrigerant pressure Pc at the refrigerant outlet 26 and the small-diameter hole portion 19b in the guide hole 19. A pressure equalizing hole 51 that leads to a pressure equalizing pressure introduction chamber 52 formed between the lower large diameter hole portion 19A and the lower large diameter portion 15A of the small diameter portion 15b of the valve rod 15 is formed. Yes. The pressure equalizing hole 51 extends from the lower end to the front of the small diameter portion 15b so as to pass through the central portion of the valve rod 15, and a plurality of pressure equalizing holes 51 open to the pressure equalizing pressure introduction chamber 52 at the upper end. With a horizontal hole. In addition, three ring-shaped grooves 15c are formed on the outer periphery of the portion (near the lower end) of the large diameter portion 19A of the valve stem 15 that is in sliding contact with the guide hole 19.

  In the control valve 1 configured as described above, when the solenoid portion including the coil 32, the stator 33, and the attractor 34 is energized and energized, the plunger 37 is attracted to the attractor 34. Is moved upward (in the valve closing direction) by the urging force of the valve closing spring 48. On the other hand, the refrigerant having the suction pressure Ps introduced from the compressor to the suction pressure introduction port 27 communicates with the longitudinal grooves 37a, 37a,... Formed in the outer periphery of the plunger 37 from the introduction chamber 23 and the suction element 39. The bellows body 40 (inside the vacuum pressure) is expanded and contracted according to the pressure in the pressure sensitive chamber 45 (suction pressure Ps), and contracts and decreases when the suction pressure Ps is high. The displacement is transmitted to the valve stem 15 via the actuating rod 14 and the plunger 37, thereby adjusting the valve opening (effective passage cross-sectional area between the valve port 22 and the valve body 15a). Is done. That is, the opening degree of the valve includes the attraction force of the plunger 37 by the solenoid portion including the coil 32, the stator 33 and the attraction element 34, the urging force of the bellows body 40, the urging force by the valve opening spring 47 and the valve closing spring 48, In accordance with the valve opening, the amount of discharge pressure Pd introduced from the discharge pressure refrigerant introduction port 25 into the valve chamber 21 to the refrigerant outlet 26 side, that is, the crank chamber is adjusted (throttle amount). As a result, the pressure (supply pressure) Pc in the crank chamber is controlled.

  In the variable displacement compressor control valve 1 of the present embodiment, the pressure on the refrigerant outlet side (supply pressure Pc to the crank chamber) acting on the valve body 15 a of the valve rod 15 is formed in the valve rod 15. Then, the pressure is introduced into the pressure equalizing pressure introduction chamber 52 through the pressure equalizing hole 51 and works in the direction of pushing down the valve rod 15, that is, in the direction of reducing (cancelling) the differential pressure between the supply pressure Pc and the suction pressure Ps. . For this reason, even if the valve port 22 is enlarged and the refrigerant flow rate is increased to adapt to a large-capacity compressor, the valve stem (valve part) is moved upward by the differential pressure between the supply pressure Pc and the suction pressure Ps. It is no longer pushed upward (closed direction), and the control problem is solved. As a result, it is possible to provide a control valve that can be applied to a large-capacity compressor while sharing parts with other control valves.

  Further, a part of the refrigerant introduced into the valve chamber 21 from the discharge pressure refrigerant inlet 25 passes between the sliding contact surfaces of the large-diameter portion 15A and the large-diameter hole portion 19A of the valve rod 15, and the pressure equalizing pressure introduction chamber 52. From here, it is led out to the refrigerant outlet 26 through the pressure equalizing hole 51. In other words, there is almost no leakage from the discharge pressure Pd to the suction pressure Ps in the conventional control valve, and the discharge pressure Pd goes to the supply pressure Pc side, so that the control is not adversely affected. Improvement and the like.

  Further, since the ring-shaped groove 15c is formed in the valve rod 15, the labyrinth effect by the ring-shaped groove 15c reduces leakage from the discharge pressure Pd to the supply pressure Pc, and the ring-shaped groove 15c Since the minute foreign matter entering between the sliding contact surfaces of the valve stem 15 and the guide hole 19 is captured, the minute foreign matter is less likely to be clogged between the sliding contact surfaces of the valve stem 15 and the guide hole 19, and the valve stem 15 is malfunctioning. For example, even if the plunger 37 is attracted to the suction element 34, it is possible to obtain an effect that it is difficult to cause a situation in which the valve stem 15 is left without being moved upward.

The longitudinal section showing one embodiment of the control valve for variable capacity type compressors concerning the present invention. FIG. 2 is an enlarged longitudinal sectional view of a main part of the control valve shown in FIG. 1. The longitudinal cross-sectional view which shows an example of the conventional control valve for variable displacement compressors.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control valve 14 for variable capacity type compressors Actuating rod 15 Valve rod 15A Large diameter portion 15a Valve body portion 15b Small diameter portion 15c Ring-shaped groove 19 Guide hole 19A Large diameter portion 19b Small diameter hole portion 20 Valve body 21 Valve chamber 22 Valve port 23 suction pressure refrigerant introduction chamber 25 discharge pressure refrigerant introduction port 26 refrigerant outlet 27 suction pressure refrigerant introduction port 30 electromagnetic actuator 32 coil 33 stator 34 suction element 35 pipe 37 plunger 40 bellows body 45 pressure sensing chamber 47 valve opening spring 48 valve closing Spring 51 Pressure equalizing hole 52 Pressure introducing chamber for pressure equalization

Claims (3)

A valve stem having a valve body portion, a guide hole into which the valve stem is slidably inserted, and a valve chamber provided with a valve port for contacting and separating the valve body portion, and upstream of the valve port A valve main body provided with a discharge pressure refrigerant inlet for introducing refrigerant at a discharge pressure from the compressor on the side, and provided with a refrigerant outlet communicating with the crank chamber of the compressor on the downstream side of the valve port; An electromagnetic actuator for driving the valve stem in the valve opening / closing direction, and a pressure sensitive responsive member for driving the valve stem in the valve opening / closing direction in response to the suction pressure of the compressor,
A small-diameter hole is provided in the upper portion of the guide hole, and a small-diameter portion that is slidably fitted into the small-diameter hole is provided in the upper portion of the valve stem. The valve rod is supplied with a refrigerant pressure at the refrigerant outlet. A pressure equalizing hole that leads to a pressure equalizing pressure introduction chamber formed between a large diameter hole portion below the small diameter hole portion in the guide hole and a large diameter portion below the small diameter portion in the valve rod. A control valve for a variable displacement compressor characterized by being formed. A valve stem having a valve body portion, a guide hole into which the valve stem is slidably inserted, and a valve chamber provided with a valve port for contacting and separating the valve body portion, and upstream of the valve port A valve body provided with a discharge pressure refrigerant inlet for introducing refrigerant at a discharge pressure from the compressor on the side, and provided with a refrigerant outlet communicating with the crank chamber of the compressor on the downstream side of the valve port, and a coil An electromagnetic type having a cylindrical stator disposed on the inner peripheral side of the coil, an attractor fixed to the stator, and a plunger disposed slidably in the vertical direction below the attractor An actuator, a pressure-sensitive chamber formed above the suction element on the inner peripheral side of the stator and into which suction pressure is introduced from the compressor, a pressure-sensitive response member disposed in the pressure-sensitive chamber, An actuating rod disposed between the pressure sensitive member and the plunger,
When the plunger is attracted to the suction element, the valve body portion is moved in the valve closing direction, and when the operating rod is pushed downward by the pressure sensitive response member, the valve body is accordingly moved. The variable displacement compressor control valve is configured to move in the valve opening direction, and a small-diameter hole is provided above the guide hole, and the small-diameter hole is slid above the valve rod. A small-diameter portion that is movably inserted is provided, and a refrigerant pressure at the refrigerant outlet is applied to the valve rod so that a large-diameter hole portion below the small-diameter hole portion in the guide hole and A control valve for a variable displacement compressor, characterized in that a pressure equalizing hole leading to a pressure equalizing pressure introducing chamber formed between the lower large-diameter portion is formed.   3. The control valve for a variable displacement compressor according to claim 1, wherein a ring-shaped groove is formed on an outer periphery of a portion of the valve rod that is in sliding contact with the large-diameter hole portion of the guide hole.

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