KR20100091878A - Control valve - Google Patents

Abstract

PURPOSE: A control valve is provided to perform accurate control by making the force of a valve opening direction by the pressure of the refrigerant applied to a rod equal to that of a valve closing direction. CONSTITUTION: A control valve comprises a rod(15), a body(20), and a pressure reducing member(40). The rod comprises an upper shaft(15c), a body(15a), and a lower shaft(15d). The body comprises a chamber(21) in which a seat(22) is formed, an upper guide hole(19A), a lower guide hole(19B), a discharge pressure port(25), and a control pressure port(26). The upper shaft of the rod is freely inserted into the upper guide hole. The lower shaft of the rod is freely inserted into the lower guide hole. The refrigerant of a discharge pressure from a compressor is induced through the discharge pressure port. The control pressure port is communicated with the crank chamber of the compressor. The pressure reducing member drives the rod in the direction of opening/closing the seat. An intake pressure passage(70) is formed on the lower part of the rod. The intake pressure passage induces the intake pressure to the pressure reducing member.

Description

CONTROL VALVE

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control valve for a variable displacement compressor for use in a car air conditioner and the like, and more particularly to a control valve for a variable displacement compressor that makes it less likely to be adversely affected by the control of refrigerant pressure acting on the valve rod.

In general, in the control valve for a variable displacement compressor used in a car air conditioner or the like, a refrigerant having a discharge pressure Pd is introduced from the compressor (discharge chamber) in order to adjust the pressure Pc in the crank chamber of the compressor. The refrigerant of the discharge pressure Pd is tightened to lead to the crank chamber, and the amount of tightening to the crank chamber (the amount of tightening) is controlled in response to the suction pressure Ps of the compressor. As also shown in the back, the use of an electronic actuator (solenoid) is provided for various proposals or practical use.

A conventional example of such a variable displacement compressor control valve is shown in FIG. The control valve 5 shown in the drawing is provided with the valve bar 21 provided with the actuating rod 14, the valve rod 15 integrated with the valve | bulb part, and the valve opening (valve seat part) 22 opened and closed by the valve body part 15a. And a discharge pressure port 25 with a plurality of filters 25A for introducing refrigerant of the discharge pressure Pd from the compressor to the outer circumferential portion of the valve chamber 21 (upstream from the valve port 22). The valve body 20 provided with the port which communicates with the crank chamber of a compressor below the valve port 22 (downstream), in other words, the control pressure port 26 for controlling the pressure of a crank chamber. And the electronic actuator 30.

The electromagnetic actuator 30 has a coil 32 having a connector portion 31 for energizing excitation, a cylindrical stator 33 disposed on an inner circumferential side of the coil 32, and a lower end portion of the stator 33. Flange shape in which the upper end is joined to the outer periphery (step) of the lower end of the stator 33 and the suction member 34 having a press-fit fixed cross section concave shape; (35a) Arranged so as to cover the pipe 35, the plunger 37 which is freely slidable in the up and down direction on the inner circumferential side of the pipe 35 from below the aspirator 34, and the outer circumference of the coil 32. The cylindrical housing 60 with the bottomed hole is provided.

In addition, an adjustment screw 65 with a hexagonal hole is screwed into the upper portion of the sdata 33, and between the adjustment screw 65 and the aspirator 34 on the inner circumferential side of the stator 33, A decompression chamber 45 into which the suction pressure Ps is introduced is formed, and in this decompression chamber 45, a bellows 41, an inverted-shaped upper stopper 42, and an inverter, which serve as a decompression reaction member, are formed. The bellows main body 40 which consists of the shaped stopper 43 and the compression coil spring 44 is arrange | positioned, and the bellows main body 40 is contracted between the bellows main body 40 and the aspirator 34. The compression coil spring 46 which is added in the direction to make (the direction compressed to the adjustment screw 65 side) is arrange | positioned. Moreover, between the lower stopper 43 (inverted recessed part) of the bellows body 40 and the recessed part 37c of the plunger 37, the step which penetrates the said aspirator 34 is attached. The actuation rod 14 is arrange | positioned, Furthermore, between the aspirator 34 and the plunger 37 (the recessed part 37b), with the compression coil spring which adds the plunger 37 downward (valve opening direction). A valve opening spring 47 is formed.

Moreover, a ring is connected to the shaft portion 15c of the valve rod 15 integrated with the operating rod 14 and the boundary portion of the large diameter portion 14b (the shaft portion 15c and the same diameter) of the operating rod 14. 15 d of shape groove parts (small diameter part) are provided, and the locking part 38 provided in the bottom part of the recessed hole 37g of the plunger 37 is fitted to the said ring-shaped groove part 15d, and the valve rod 15 is provided. ) And the plunger 37 are raised and lowered integrally.

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 is located above the valve chamber including the convex stopper portion 28. In the central portion of the guide rod 19, the valve rod 15 slides freely. In addition, between the plunger 37 and the upper outer circumference of the valve body 20 (the outer circumference of the convex stopper portion 28), a suction pressure refrigerant introduction chamber 23 through which a refrigerant at the suction pressure of the compressor is introduced is formed. A plurality of suction pressure ports 27 are formed on the outer circumferential side thereof, and the refrigerant at the suction pressure Ps introduced into the suction pressure refrigerant introduction chamber 23 from the suction pressure port 27 is formed of the plunger 37. The decompression chamber 45 is formed through the vertical grooves 37a, 37a, ... formed in the outer circumference, and the communication hole 39 partially formed in the center portion, or the gap formed between the aspirator 34 and the operating rod 14. Is introduced.

The valve closing spring 48 which consists of a conical compression coil spring which adds the said valve rod 15 upward is arrange | positioned in the lower part (control pressure port 26) of the said valve main body 20. As shown in FIG.

In addition, the lower end flange portion 35a of the pipe 35 is mounted on the upper end portion of the valve body 20 through an O-ring 57, and between the flange portion 35a and the coil 32. The pipe holder 56 of the single cylinder shape with the flange-shaped part 56a is opened, and those flange-shaped parts 35a and 56a are the upper outer peripheral caulking part 29 of the valve main body 20. It is fastened together and fixed by. Moreover, the bottom part 61 with the hole of the said housing 60 is press-fitted at the upper end part of the pipe holder 56, and the upper end part 62 of the housing 60 is a flange-shaped part (of the said connector part 31 ( The caulking is fixed on 31c), and an O-ring 66 is installed between the housing 60, the connector part 31, and the coil 32. As shown in FIG. Moreover, the recessed part 31a in which the convex part 31b which engages in the hexagonal hole of the said adjustment screw 65 is formed in the center lower part of the connector part 31, and the said recessed part 31a is mentioned above. The upper part of the stator 33 and the adjustment screw 65 is inserted.

In the control valve 5 of such a structure, when the solenoid part which consists of the coil 32, the stator 33, and the aspirator 34 is energized, the plunger 37 is attracted to the aspirator 34, In connection with this, the valve rod 15 is assisted also by the biasing force of the valve closing spring 48, and is moved upward (valve closing direction). On the other hand, the refrigerant of the suction pressure Ps introduced from the compressor to the suction pressure inlet 27 is formed in the longitudinal grooves 37a, 37a, ..., and communication holes (3) formed on the outer circumference of the plunger 37 from the introduction chamber 23. 39 is introduced into the decompression chamber 45, and the bellows main body 40 (internal vacuum pressure) is stretched in response to the pressure (suction pressure Ps) of the decompression chamber 45 (suction pressure Ps). ), The contraction is high, the extension is low, and the displacement is transmitted to the valve rod 15 through the operating rod 14 and the plunger 37, whereby the valve opening degree (the valve from the valve port 22). Lift amount of the body portion 15a) is adjusted. That is, the valve opening degree is the suction force of the plunger 37 by the solenoid part which consists of the coil 32, the stator 33, and the aspirator 34, the force of the bellows main body 40, and the valve opening spring ( 47) and the force applied by the valve closing spring 48, the valve opening direction load and the valve closing direction load acting on the valve rod 15, and depending on the valve opening degree, the discharge pressure port 25 The amount of tightening of the refrigerant of the discharge pressure Pd introduced into the valve chamber 21 from the valve chamber 21, that is, the amount of extraction (tightening amount) into the crank chamber is adjusted. In other words, in response to the valve opening degree, the pressure (control pressure) supplied from the control pressure port 26 to the crank chamber, that is, the crank chamber pressure Pc, is controlled and, accordingly, the swash plate of the compressor. The inclination angle and the stroke of the piston are adjusted, and the discharge amount is increased or decreased.

Prior art literature

Patent Literature

Patent Document 1: Japanese Patent Application Laid-Open No. 2002-303262

Patent Document 2: Japanese Patent Application Laid-Open No. 2007-205248

In the conventional control valve for variable displacement compressor 5 as described above, the pressure of the refrigerant acting on the valve rod 15 causes the following in the valve opening direction (downward) and the valve closing direction (upward), respectively. It takes power. That is, the cross-sectional area of the large-diameter shaft portion 15c (the portion sliding the guide hole 19) of the valve rod 15 is Sa, the effective opening area of the valve port 22 is Sb, the discharge pressure is Pd, and the suction pressure is Ps. When crankcase pressure (control pressure) is set to Pc,

Force in the valve opening direction = Pd × Sb + Ps × Sa

Force in the valve closing direction = Pd × Sa + Pc × Sb

Becomes

Here, since the cross-sectional area Sa of the shaft part 15c and the effective opening area Sb of the valve port 22 become substantially the same in design, and since it is crank chamber pressure Pc> suction pressure Ps, a valve rod is provided. Force in the valve opening direction and force in the valve closing direction due to the discharge pressure Pd applied to (15) are canceled, and in the valve closing direction in the valve rod 15, (Pc-Ps) x Sa (or Sb) It takes power.

In this way, if the force in the valve opening direction and the valve closing direction are different from each other due to the refrigerant pressure applied to the valve rod, the control will be adversely affected (decrease in control accuracy, etc.).

In order to solve such a problem, conventionally, as shown in the patent document 1 (FIG. 4) etc., in order to equalize the force of the valve opening direction and the valve closing direction which apply to a valve rod, In addition to providing the shaft portion at one bar, the valve body is provided with a vertical hole and a pressure chamber in which the shaft portion is slid freely, and at the lower end side (valve closing direction) of the shaft portion (valve rod). In order to apply the suction pressure Ps similar to the opening direction, it is proposed to provide a cancel passage including a vertical hole and a horizontal hole in the valve body.

However, in the control valve mechanism for the variable displacement compressor of this proposal, it is necessary to provide a vertical hole, a pressure chamber, and the like in the valve body, which leads to a complicated structure and an increase in the number of parts and the manufacturing cost. there is a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a force in a valve opening direction due to a refrigerant pressure applied to a valve rod without causing a complicated structure, an increase in the number of parts and a manufacturing cost. It is an object of the present invention to provide a control valve for a variable displacement compressor that can equalize the force in the valve closing direction and be less likely to be adversely affected by the control of the refrigerant pressure acting on the valve rod.

In order to achieve the above object, the control valve for variable displacement compressor according to the present invention basically includes an upper shaft portion, a valve body portion larger in diameter than the upper shaft portion, and a lower shaft portion equal to the upper shaft portion. A valve rod having a valve rod having a valve rod, and a valve chamber in which the valve body portion is folded, and an upper guide hole in which an upper shaft portion of the valve rod slides freely is provided above the valve sphere, and below the valve sphere. A lower guide hole through which the lower shaft portion of the rod slides freely is provided, and a discharge pressure port for introducing a refrigerant of the discharge pressure from the compressor into both sides of the valve port and a control pressure communicating with the crank chamber of the compressor. A valve body provided with a port, an electronic actuator for driving the valve rod in a valve opening opening direction, and the compressor And a suction pressure member for driving the valve rod in the valve opening / closing direction in response to suction pressure, and the suction pressure acts on the lower end of the valve rod, and the suction pressure is applied to the valve body. A suction pressure passage is provided for guiding the pressure, so that the force in the valve opening direction and the force in the valve closing direction are equal to each other due to the refrigerant pressure applied to the valve rod.

In a preferred embodiment, a suction pressure introduction loss is introduced through which the suction pressure is introduced into the lower end of the lower guide hole so that the suction pressure acts on the lower end of the valve rod.

Preferably, the suction pressure passage communicates with the pressure reducing chamber accommodating the pressure-sensitive responding member, and the other end is opened at the lower end of the valve body.

In another preferred aspect, a plunger chamber in which a plunger which is a component of the electronic actuator is disposed above the upper guide hole in the valve body is provided, and the suction pressure passage passes through the plunger chamber through the pressure reducing chamber. To communicate with.

In another preferable aspect, the valve chamber having the discharge pressure port or the control pressure chamber having the control pressure port is provided between the valve port in the valve body and the lower guide hole.

In another preferred embodiment, the plunger chamber in which the plunger which is a component of the electronic actuator is disposed is provided above the upper guide hole in the valve body, and the main body of the valve body communicates with the outside of the plunger chamber. A suction pressure port as the suction pressure passage is provided on the side.

The suction pressure passage is preferably composed of a straight through hole.

As another preferable aspect, the cylindrical body which has the lower guide hole by which the lower side shaft part of the said valve rod slides freely is slidably fixed so that the lower side of the said valve chamber or the control pressure chamber may be partitioned below the said valve port.

In the control valve for a variable displacement compressor according to the present invention, for example, a suction pressure introduction loss through which suction pressure Ps is introduced is provided at the lower end of the lower guide hole, and suction pressure Ps acts on the lower end surface of the valve rod. In addition, since the suction pressure passage for guiding the suction pressure Ps to the pressure-reducing member (pressure reducing chamber) is provided in the valve body, the valve rod is equalized if the cross-sectional area of the upper shaft portion and the lower shaft portion of the valve rod is the same. The force applied in the valve opening direction and the force applied in the valve closing direction by the discharge pressure Pd and the crankcase pressure Pc acting on each other become equal (offset), and the suction pressure Ps acting on the valve rod. The force applied in the valve opening direction and the valve closing direction are the same (offset), and as a result, the force in the valve opening direction due to the refrigerant pressure applied to the valve rod becomes equal to the force in the valve closing direction. Therefore, it is difficult to be adversely affected by the control by the refrigerant pressure acting on the valve rod.

In addition, basically, the valve main body only needs to be provided with a suction pressure passage made of, for example, a straight through hole, so that the structure is simpler than the conventional one, and the number of parts and the increase in manufacturing cost are suppressed. can do.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described, referring drawings.

1 is a longitudinal sectional view showing one embodiment (first embodiment) of a control valve for a variable displacement compressor according to the present invention. In the control valve 1 for variable displacement compressor shown in FIG. 1, the part corresponding to each part of the variable displacement compressor control valve 5 of the conventional example shown in FIG. 3 is attached | subjected with the same code | symbol, and is overlapped. Description will be omitted and the differences will be mainly described below.

The illustrated control valve 1 includes a valve rod 15 which is integrally connected to the operating rod 14. The valve rod 15 has a small diameter portion 15b smaller in diameter than the upper shaft portion 15c, the upper shaft portion 15c, a valve body portion 15a larger in diameter than the upper shaft portion 15c, and the upper shaft portion 15c. It has the lower shaft part 15e of the longitude. Moreover, the lower end part (concave hole part) 14b of the operating rod 14 is connected and fixed to the upper part (convex-shaped part) of the valve rod 15 by press injection etc., and the annular groove part (small diameter part) is provided below this connection fixing part. 15d is provided, and the locking portion 38 provided at the bottom of the plunger 37 is fitted to the annular groove 15d so that the valve rod 15 and the plunger 37 are raised and lowered integrally. It is.

On the other hand, the valve body 20 has a valve chamber 21 provided with a valve port (valve seat part) 22 in which the valve body part 15a is folded, and the valve rod is located above the valve port 22. An upper guide hole 19A through which the upper shaft portion 15c of 15 is freely slidably provided is provided, and below the valve port 22, the valve rod 21 is partitioned so as to partition the lower surface of the valve chamber 21. The cylindrical body 52 which has the lower guide hole 19B to which the lower shaft part 15e of 15) slides freely is inserted and fixed.

In addition, a discharge pressure port 25 for inserting a refrigerant of the discharge pressure Pd from the compressor into the lower valve chamber 21 by inserting the valve port 22 in the valve body 20 is provided. A control pressure chamber 26A having a control pressure port 26 communicating with the sphere 22 and communicating with the crank chamber (pressure Pc) of the compressor is provided above.

In addition, at the lower end of the lower guide hole 19B in the cylindrical body 52, a suction pressure introduction loss 72 (toward the lower guide hole 19B) in which suction pressure Ps is introduced is provided. In order to guide the suction pressure Ps to the pressure reduction chamber 45 (the bellows main body 40), the valve main body 20 comprises a straight through hole (small diameter hole 70a and large diameter hole 70b). A suction pressure passage 70 is provided. One end (upper end) of the suction pressure passage 70 communicates with the pressure reducing chamber 45 via the plunger chamber 24, and the other end is opened at the lower end of the valve body 20.

The control valve 1 which has such a structure is provided in the valve mounting hole (hole with a step) 80 formed in the swash plate chamber vicinity of the body housing 100 of a variable displacement compressor. Are assembled. A snap ring (C-shaped ring) 81 for preventing release is attached to the upper portion of the valve mounting hole 80, and the snap ring 81 abuts against the upper end (caking portion) 62 of the housing 60. There is me. In addition, the gas housing 100 communicates with a discharge pressure port 25, a control pressure port 26, and a Ps introduction chamber 88, a suction pressure introduction chamber 72, and a suction pressure passage 70 described later. The Pd passage 92, the Pc passage 93, and the Ps passage 91 are provided. In addition, O-rings 82, 83, and 84 are disposed at a necessary place between the outer circumferential surface of the control valve 1 and the inner circumferential surface of the valve mounting hole 80 so that Pd, Pc, and Ps do not leak.

The Ps introduction chamber 88 is provided between the bottom part (lower part) of the valve mounting hole 80 and the lower end part of the valve main body 20, and the suction pressure introduced into the Ps introduction chamber 88 through the Ps passage 91 is provided. The refrigerant of Ps is a force for pushing the valve rod 15 in the valve closing direction by the suction pressure port 72, and is led to the plunger chamber 24 through the suction pressure passage 70 to obtain the valve rod ( It is a force to push 15) in the valve opening direction.

In the control valve 1 having such a configuration, the following forces are applied in the valve opening direction (downward) and the valve closing direction (upward), respectively, by the pressure of the refrigerant acting on the valve rod 15. In other words, the cross-sectional area of the upper shaft portion 15c (the portion sliding the upper guide hole 19A) of the valve rod 15 is Sa, the effective opening area of the valve port 22 is Sb, and the lower shaft portion of the valve rod 15 is shown. If the cross-sectional area of 15e (part sliding the lower guide hole 19B) is Sc, the discharge pressure is Pd, the suction pressure is Ps, and the crankcase pressure is Pc,

Force in the valve opening direction = Pd × Sc + Pc × Sb + Ps × Sa

Force in the valve closing direction = Pd × Sb + Pc × Sa + Ps × Sc

Becomes

Here, since the cross-sectional area Sa of the upper shaft part 15c, the effective opening area Sb of the valve opening 22, and the cross-sectional area Sc of the lower shaft part 15e become substantially the same in design, Pd x Sc = Pd x Sb, Pc x Sb = Pc x Sa, Ps x Sa = Ps x Sc, and the force applied in the valve opening direction = the force applied in the valve closing direction.

As described above, the control valve 1 of the present embodiment is provided with a suction pressure introduction chamber 72 through which the suction pressure Ps is introduced into the lower guide hole 19B (D: end), and the lower end surface of the valve rod 5. Since the suction pressure Ps acts on the valve body 20 and the suction pressure passage 70 is formed in the valve body 20 to guide the suction pressure Ps to the decompression chamber 45, the valve rod 15 is provided. When the upper shaft portion 15c of the lower shaft portion 15e and the cross-sectional area Sa, Sc, Sb of the valve opening 22 are equal, the discharge pressure Pd and the crankcase pressure Pc acting on the valve rod 15 are equal. The force applied in the valve opening direction by the valve opening direction and the valve closing direction are equal to (offset), and the force applied in the valve opening direction by the suction pressure Ps acting on the valve rod 15 and the valve closing direction. The force applied in the valve is equal to (offset), and as a result, the force in the valve opening direction and the valve closing direction due to the refrigerant pressure applied to the valve rod 15 Since it becomes the same, it becomes difficult to be adversely affected by the control by the refrigerant pressure acting on the valve rod 15.

In addition, since it is only necessary to provide a suction pressure passage 70 formed of a straight through hole in the valve body 20, the structure is simpler than the conventional one, and the number of parts and manufacturing cost are increased. Etc. can be suppressed.

2 is a longitudinal sectional view showing a second embodiment of a control valve for a variable displacement compressor according to the present invention. In the control valve 2 for variable displacement compressor shown in FIG. 2, the same code | symbol is attached | subjected to the part corresponding to each part of the control valve for variable displacement compressor 1 and 5 shown in FIG. 1 and FIG. 3 mentioned above. The duplicate description is abbreviate | omitted, and the following focuses on a difference.

In this example, the valve main body 20 (20A) has the valve chamber 21 provided with the valve opening (valve seat part) 22 which the said valve body part 15a folds, and is higher than the said valve opening 22. The upper guide hole 19A in which the upper shaft part 15c of the said valve rod 15 slides freely is provided, and below the said valve opening 22, the lower surface of the said valve chamber 21 is partitioned so that the said The cylindrical body 20B which has the lower guide hole 19B in which the lower shaft part 15e of the valve rod 15 slides freely is inserted and fixed.

In addition, a suction pressure introduction chamber 73 is provided in which a suction pressure Ps is introduced at a lower end portion of the lower guide hole 19B in the cylindrical body 52.

In the control valve 2, the suction pressure passage 70 provided in the control valve 1 of the first embodiment does not exist, but the upper portion of the valve body 20 (above the control pressure port 26). The suction pressure port 27 as a suction pressure passage similar to that of the conventional example is provided in the chamber. That is, a convex stopper portion 28 for regulating the lowest position of the plunger 37 protrudes from the upper center of the valve body 20, and includes the convex stopper portion 28. A guide hole 19A through which the upper shaft portion 15c of the valve rod 15 slides freely is formed in a central portion above the valve chamber. In addition, between the plunger 37 and the upper outer circumference (the outer circumference of the convex stopper portion 28) of the valve body 20, the suction pressure refrigerant introduction chamber 23 into which the refrigerant at the suction pressure Ps of the compressor is introduced is provided. While being formed, a plurality of suction pressure ports 27 are formed on the outer circumferential side thereof, and the refrigerant having the suction pressure Ps introduced into the suction pressure refrigerant introduction chamber 23 from the suction pressure port 27 thereof is a plunger. The decompression chamber (37) is formed through the vertical grooves 37a, 37a, ... formed in the outer circumference of the 37 and the communication hole 39 partially formed in the central portion, or the gap formed between the aspirator 34 and the operating rod 14, and the like. 45).

The control valve 2 having such a configuration is assembled to a valve mounting hole (hole with an end) 80 formed in the vicinity of the swash plate chamber in the gas housing 100 of the variable displacement compressor. A snap ring (C-shaped ring) 81 for preventing release is attached to the upper portion of the valve mounting hole 80, and the snap ring 81 abuts against the upper end (caulking portion) 62 of the housing 60. It is meant to be built. The gas housing 100 has a discharge pressure port 25, a control pressure port 26, and Pd communicating with the Ps introduction chamber 88, the suction pressure introduction chamber 73, and the suction pressure port 27. A passage 92, a Pc passage 93, and a Ps passage 91 (branches into 9la and 91b) are provided. In addition, O-rings 82, 83, 84, and 85 are disposed at a necessary position between the outer circumferential surface of the control valve 2 and the inner circumferential surface of the valve mounting hole 80 so that Pd, Pc, and Ps do not leak.

The Ps introduction chamber 88 is provided between the bottom part (lower part) of the valve mounting hole 80 and the lower end part of the valve main body 20, and the Ps introduction chamber 88 is provided through the branch path 91a of the Ps passage 91. The refrigerant having the suction pressure Ps introduced into the force becomes a force for pushing the valve rod 15 in the valve closing direction from the suction pressure introduction chamber 73, and the branch path 91b of the Ps passage 91 and The refrigerant at the suction pressure Ps introduced into the suction pressure refrigerant introduction chamber 23 through the suction pressure port 27 serves as a force for pushing the valve rod 15 down in the valve opening direction.

Also in the control valve 2 of the present embodiment having such a configuration, the overall length of the valve tends to be longer than that of the first embodiment, but an effect similar to that of the first embodiment can be obtained.

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

2 is a longitudinal sectional view showing a second embodiment of a control valve for a variable displacement compressor according to the present invention;

3 is a longitudinal sectional view showing an example of a conventional control valve for a variable displacement compressor.

Explanation of the sign

1, 2: control valve for variable displacement compressor

15: valve rod

15a: valve body

15c: upper shaft

15e: Lower shaft

19A: Upper guide hole

19B: Lower guide hole

20: valve body

21: valve chamber

22: valve opening (valve seat)

23: suction pressure refrigerant introduction chamber

24: Plunger Room

25: discharge pressure port

26: control pressure port

27: suction pressure port

30: electronic actuator

32: coil

33: Stator

34: aspirator

35: pipe

37: plunger

40: Bellows body

45: decompression chamber

47: valve opening spring

48: valve closing spring

70: suction pressure passage

72, 73: suction pressure loss

Claims (8)

A valve rod having an upper shaft portion, a valve body portion larger in diameter than the upper shaft portion, and a lower shaft portion equal to the upper shaft portion; The valve body is provided with a valve chamber for folding the valve body portion, an upper guide hole through which the upper shaft portion of the valve rod slides freely is provided above the valve sphere, and the lower shaft portion of the valve rod slides lower than the valve opening. A valve body provided with a freely subtracted lower guide hole, a discharge pressure port for inserting the valve opening and introducing refrigerant at the discharge pressure from the compressor on both sides and a control pressure port communicating with the crank chamber of the compressor. Wow, An electronic actuator for driving the valve rod in the valve opening / closing direction, and a pressure-sensitive actuating member for driving the valve rod in the valve opening / closing direction in response to the suction pressure of the compressor, While the suction pressure is applied to the lower end of the valve rod, a suction pressure passage is provided in the valve body so as to guide the suction pressure to the pressure-sensitive responding member. The control valve for a variable displacement compressor, characterized in that the force in the valve opening direction and the force in the valve closing direction by the refrigerant pressure applied to the valve rod is the same. The method of claim 1, And a suction pressure introduction loss through which the suction pressure is introduced into the lower end of the lower guide hole so that the suction pressure acts on the lower end of the valve rod. The method according to claim 1 or 2, The suction pressure passage has one end in communication with a pressure reducing chamber accommodating the pressure-sensitive actuating member, and the other end thereof is opened at the lower end of the valve body. The method of claim 3, wherein The plunger chamber in which the plunger which is a component of the said electric actuator is arrange | positioned above the said upper guide hole in the said valve main body is provided, and the said suction pressure path communicates with the said pressure reduction chamber via the said plunger chamber. A control valve for a variable displacement compressor. The method according to any one of claims 1 to 4, The valve chamber having the discharge pressure port or the control pressure chamber having the control pressure port is provided between the valve port in the valve body and the lower guide hole. The method according to claim 1 or 2, The plunger chamber in which the plunger which is a component of the said electric actuator is arrange | positioned above the said upper guide hole in the said valve main body is provided, and the main side part of the said valve main body so that the plunger chamber may communicate with the outside. ) Is provided with a suction pressure port as the suction pressure passage. The method according to any one of claims 1 to 6, The control valve for a variable displacement compressor, characterized in that the suction pressure passage is composed of a straight through hole. The method according to any one of claims 5 to 7, A variable capacity type is characterized in that a tubular body having a lower guide hole through which the lower shaft portion of the valve rod slides freely is inserted into the lower side of the valve chamber so as to partition the lower surface of the valve chamber or the control pressure chamber. Control valve for the compressor.

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