JP2014080927A - Control valve for variable displacement compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control valve for a variable displacement compressor which improves flexibility of design of a valve part and a pressure sensitive part, in the control valve for the variable displacement compressor having the pressure sensitive part.SOLUTION: A control valve 1 includes: a body 5 formed of a volume chamber 22, a valve chamber 26 and an actuation chamber 28 from one edge side; a valve body which is supported slidably on the body 5, receives a crank pressure in the volume chamber 22 on one edge side, on the other hand, receives a pressure to be sensed in the actuation chamber 28 on the other edge side and attaches to and detaches from a valve seat disposed between the valve chamber 26 and the volume chamber 22 to open and close a valve body; and a power element 6 which senses the crank pressure in the volume chamber 22 and biases the valve body in the valve opening direction in accordance with the crank pressure. A pressure chamber 88 into which the crank pressure of the volume chamber 22 is introduced is formed on the side opposite to the volume chamber 22 with respect to the valve chamber 26, and an actuation surface 87 which receives the crank pressure in the pressure chamber 88 is provided on the valve body.

Description

  The present invention relates to a control valve suitable for controlling the discharge capacity of a variable capacity compressor.

  In general, an air conditioner for an automobile compresses the refrigerant flowing through the refrigeration cycle and discharges it as a high-temperature / high-pressure gas refrigerant, a condenser that condenses the gas refrigerant, and adiabatic expansion of the condensed liquid refrigerant. And an expansion device that converts the refrigerant into a low-temperature and low-pressure refrigerant, an evaporator that exchanges heat with the air in the vehicle interior by evaporating the refrigerant, and the like. The refrigerant evaporated in the evaporator is returned to the compressor and circulates in the refrigeration cycle.

  As this compressor, a variable capacity compressor (also simply referred to as “compressor”) capable of varying the refrigerant discharge capacity is used so that a constant cooling capacity is maintained regardless of the engine speed. In this compressor, a piston for compression is connected to a swing plate attached to a rotary shaft that is driven to rotate by an engine, and the discharge amount of the refrigerant is changed by changing the stroke of the piston by changing the angle of the swing plate. adjust. The angle of the swing plate can be continuously changed by introducing a part of the discharged refrigerant into the sealed crank chamber and changing the balance of pressure applied to both surfaces of the piston. The pressure in the crank chamber (hereinafter referred to as “crank pressure”) Pc is controlled by a variable displacement compressor control valve (also simply referred to as “control valve”) provided between the discharge chamber and the crank chamber of the compressor. The

  Such a control valve adjusts the valve opening degree by supplying current from the outside to a solenoid as a drive unit. When it is necessary to quickly exhibit the air conditioning function, such as when the air conditioner is started, the valve portion is closed by supplying a maximum current to the solenoid, for example, the crank pressure Pc is lowered and the swing plate is used as the rotating shaft. In contrast, the compressor can be operated at the maximum capacity by being tilted greatly. When the engine load on the vehicle is large, the solenoid is turned off to fully open the valve, and the crank pressure Pc is increased to make the swing plate substantially perpendicular to the rotating shaft, thereby reducing the compressor with the minimum capacity. Can be driven.

  As such a control valve, for example, there is a valve that controls the crank pressure Pc by adjusting the amount of refrigerant introduced into the crank chamber in accordance with the suction pressure Ps (see, for example, Patent Document 1). This control valve senses and displaces the suction pressure Ps, receives a driving force from the pressure sensing unit, controls a valve that opens and closes a passage from the discharge chamber to the crank chamber, and a driving force by the pressure sensing unit. And a solenoid capable of varying the set value by an external current. This control valve opens and closes the valve portion so that the suction pressure Ps is maintained at a set pressure set by an external current. In general, since the suction pressure Ps is proportional to the refrigerant temperature at the evaporator outlet, freezing or the like of the evaporator can be prevented by maintaining the set pressure at a predetermined value or higher. In particular, the control valve described in the cited document 1 is provided with a pressure-sensitive portion at the end opposite to the solenoid of the body, so there is no need to arrange a pressure-sensitive member between the valve body and the solenoid. There is an advantage that the valve can be realized with a simple configuration.

JP 2008-240580 A

  By the way, in such a control valve, since the suction pressure Ps to be sensed is introduced from a port away from the pressure-sensitive portion, it is difficult to directly receive the suction pressure Ps by the pressure-sensitive member. In view of this, a configuration is adopted in which the pressure sensing unit operates by substantially sensing the suction pressure Ps by devising the pressure receiving balance of the valve body and the pressure sensing member and canceling the influence of the crank pressure Pc acting on them. ing. That is, by making the effective pressure receiving area of the valve body equal to the effective pressure receiving area of the pressure sensitive member in the capacity chamber in which the valve body and the pressure sensing portion are opposed to each other and the crank pressure Pc is introduced, the crank pressure Pc The effect of canceling.

  However, in such a configuration, the size of the valve body must be set according to the pressure-sensitive member, or conversely, the size of the pressure-sensitive member must be set according to the valve body. There is a problem in that the degree of freedom in design of parts is restricted.

  This invention is made | formed in view of such a subject, and it aims at improving the design freedom of a valve part and a pressure sensitive part in the control valve for variable capacity compressors provided with a pressure sensitive part.

  In order to solve the above-described problem, an aspect of the present invention provides a refrigerant that introduces the discharge capacity of a variable capacity compressor that compresses the refrigerant introduced into the suction chamber and discharges the refrigerant from the discharge chamber into the crank chamber, And a variable capacity compressor control valve that is changed by adjusting the flow rate or pressure of at least one of the refrigerant led out from the crank chamber to the suction chamber, and a valve that communicates from one end side to the crank chamber and a discharge chamber A body in which a working chamber into which a sensed pressure is introduced is formed, and a body that is slidably supported by the body, receives the crank pressure in the capacity chamber on one end side, and receives the crank pressure in the working chamber on the other end side. A valve body that receives the sensed pressure, attaches and detaches to a valve seat provided between the valve chamber and the capacity chamber, opens and closes the valve portion, and senses the crank pressure in the capacity chamber, and the valve body according to the crank pressure Sense of energizing the valve in the valve opening direction It comprises a part, a. A pressure chamber into which the crank pressure of the capacity chamber is introduced is formed on the side opposite to the capacity chamber with respect to the valve chamber, and an operating surface for receiving the crank pressure in the pressure chamber is provided on the valve body.

  According to this aspect, the valve body receives the crank pressure in the capacity chamber on one end side and receives the sensed pressure in the working chamber on the other end side, and is formed on the side opposite to the capacity chamber with respect to the valve chamber. Also in the pressure chamber, the crank pressure is received by the operating surface. For this reason, even if the valve body is formed to a desired size, it is possible to adjust the pressure receiving balance with the pressure sensing unit by adjusting the size, shape, pressure receiving direction, etc. of the operating surface accordingly. It becomes. As a result, the degree of freedom in designing the valve part and the pressure sensitive part can be improved.

  ADVANTAGE OF THE INVENTION According to this invention, in the control valve for variable capacity compressors provided with a pressure sensitive part, the design freedom of a valve part and a pressure sensitive part can be improved.

It is sectional drawing which shows the structure of the control valve which concerns on 1st Embodiment. It is a partial expanded sectional view corresponding to the upper half part of FIG. It is a figure showing operation | movement of a control valve. It is a figure showing operation | movement of a control valve. It is a partial expanded sectional view corresponding to the upper half part of the control valve concerning a 2nd embodiment. It is a partial expanded sectional view corresponding to the upper half part of the control valve concerning a 3rd embodiment. It is a partial expanded sectional view corresponding to the upper half part of the control valve concerning a 4th embodiment. It is a partial expanded sectional view corresponding to the upper half part of the control valve concerning a 5th embodiment.

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 control valve according to the first embodiment.
The control valve 1 is configured as an electromagnetic valve that controls the discharge capacity of a variable capacity compressor (not shown) (simply referred to as “compressor”) installed in the refrigeration cycle of the automotive air conditioner. This compressor compresses the refrigerant flowing through the refrigeration cycle and discharges it as a high-temperature and high-pressure gas refrigerant. The gas refrigerant is condensed in a condenser (external heat exchanger) and further adiabatically expanded by an expansion device to become a low temperature / low pressure mist refrigerant. The low-temperature and low-pressure refrigerant evaporates in the evaporator, and the passenger compartment air is cooled by the latent heat of vaporization. The refrigerant evaporated in the evaporator is returned again to the compressor and circulates in the refrigeration cycle. The compressor has a rotating shaft that is rotationally driven by an automobile engine, and a compression piston is connected to a swing plate attached to the rotating shaft. The refrigerant discharge amount is adjusted by changing the stroke of the piston by changing the angle of the swing plate. The control valve 1 controls the flow rate of the refrigerant introduced from the discharge chamber of the compressor into the crank chamber, thereby changing the angle of the swing plate, and thus the discharge capacity of the compressor.

  The control valve 1 is configured as a so-called Ps sensing valve that controls the flow rate of the refrigerant introduced from the discharge chamber into the crank chamber so as to keep the suction pressure Ps (corresponding to “sensed pressure”) of the compressor at a set pressure. Yes. The control valve 1 is configured by integrally assembling a valve body 2 and a solenoid 3. The valve body 2 is a main valve that opens and closes a refrigerant passage for introducing a part of the discharged refrigerant into the crank chamber when the compressor is in operation, and a so-called bleed valve that releases the refrigerant in the crank chamber to the suction chamber when the compressor is started. Including a functioning secondary valve. The solenoid 3 controls the flow rate of the refrigerant introduced into the crank chamber by driving the main valve in the opening / closing direction to adjust the opening degree. The valve body 2 includes a stepped cylindrical body 5, a main valve and a sub valve provided in the body 5, a power element 6 that generates a force that opposes the solenoid force to adjust the opening of the main valve, and the like. I have. The power element 6 functions as a “pressure sensitive part”.

  The control valve 1 is provided with ports 12, 14, and 16 from the upper end side. Of these, the port 12 is provided at the upper end opening of the body 5, and the port 14 is provided at the side of the body 5. The port 16 is provided in an extending portion of the core 46 that extends upward from the solenoid 3. The port 12 functions as a “crank chamber communication port” communicating with the crank chamber, the port 14 functions as a “discharge chamber communication port” communicating with the discharge chamber, and the port 16 is a “suction chamber communication port” communicating with the suction chamber. Function as. An end member 13 is fixed to the upper end opening of the body 5. The refrigerant is introduced or led out through a plurality of communication grooves 15 provided on the outer peripheral surface of the end member 13. The lower end of the body 5 is connected to the upper end of the solenoid 3. In the body 5, a main passage that communicates the port 12 and the port 14 and a sub passage that communicates the port 12 and the port 16 are formed. A main valve is provided in the main passage, and a sub valve is provided in the sub passage. A main valve hole 18 is provided in the main passage, and a main valve seat 20 is formed on the tapered surface of the lower end opening edge.

  The port 14 introduces a refrigerant having a discharge pressure Pd from the discharge chamber. The port 12 guides the refrigerant having the crank pressure Pc via the main valve toward the crank chamber during steady operation of the compressor, and introduces the refrigerant having the crank pressure Pc discharged from the crank chamber when the compressor is started. The refrigerant introduced at this time is guided to the auxiliary valve. Between the port 12 and the main valve hole 18, a capacity chamber 22 that is filled with the crank pressure Pc is formed. The power element 6 is disposed in the capacity chamber 22. The port 16 introduces the refrigerant having the suction pressure Ps during the steady operation of the compressor, and guides the refrigerant having the suction pressure Ps via the sub valve toward the suction chamber when starting the compressor. An annular strainer 17 is attached to the port 14. The strainer 17 includes a filter for suppressing entry of foreign matter into the body 5. On the other hand, a bottomed cylindrical strainer 11 is attached to the port 12. The strainer 11 includes a filter for suppressing entry of foreign matter into the body 5.

  A valve chamber 26 is provided on the opposite side of the main valve hole 18 from the capacity chamber 22 and communicates with the port 14. On the opposite side of the valve chamber 26 from the main valve hole 18, a guide hole 24 is formed coaxially with the main valve hole 18. A working chamber 28 is formed on the opposite side of the guide hole 24 from the valve chamber 26 and communicates with the port 16. A stepped cylindrical main valve element 30 is slidably inserted into the guide hole 24. The main valve body 30 opens and closes the main valve by being attached to and detached from the main valve seat 20 from the valve chamber 26 side, and adjusts the flow rate of refrigerant flowing from the discharge chamber to the crank chamber. On the other hand, the main valve body 30 is provided with a sub valve hole 32, and a sub valve seat 34 is formed at the upper end opening of the sub valve hole 32. A lower portion of the main valve body 30 extends to the working chamber 28. A stepped columnar subvalve element 36 is disposed in the capacity chamber 22. The auxiliary valve body 36 is disposed opposite to the main valve body 30 in the axial direction, and opens and closes the auxiliary valve by being attached to and detached from the auxiliary valve seat 34.

  Further, an elongated operating rod 38 is provided along the axis of the body 5. The upper end of the actuating rod 38 is connected to the power element 6 via the auxiliary valve body 36 so as to be operatively connectable, and the lower end is connected to a plunger 50 (to be described later) of the solenoid 3. The upper half of the actuating rod 38 is inserted into the main valve body 30 and supports the sub-valve body 36 from below at the tip. Between the main valve body 30 and the solenoid 3, a spring 42 (functioning as an “urging member”) for biasing the main valve body 30 in the valve closing direction of the main valve is interposed. On the other hand, a spring receiving member 25 is press-fitted into the upper half of the body 5, and the auxiliary valve body 36 is urged between the spring receiving member 25 and the auxiliary valve body 36 in the closing direction of the auxiliary valve. In addition, a spring 44 (which functions as an urging member) that can urge the main valve body 30 in the valve opening direction of the main valve is interposed.

  On the other hand, the power element 6 includes a bellows 45 (functioning as a “pressure-sensitive member”) that senses and displaces the crank pressure Pc, and generates a force that opposes the solenoid force by the displacement of the bellows 45. This counter force is also transmitted to the main valve body 30 via the auxiliary valve body 36. When the auxiliary valve body 36 is seated on the auxiliary valve seat 34 and closes the auxiliary valve, the relief of the refrigerant from the crank chamber to the suction chamber is blocked. Further, when the auxiliary valve body 36 is separated from the auxiliary valve seat 34 and opens the auxiliary valve, the refrigerant is allowed to be relieved from the crank chamber to the suction chamber.

  On the other hand, the solenoid 3 includes a stepped cylindrical core 46, a bottomed cylindrical sleeve 48 assembled so as to seal the lower end opening of the core 46, and the sleeve 46 accommodated in the axial direction of the core 46. A cylindrical plunger 50 disposed opposite to the core 46, a cylindrical bobbin 52 extrapolated to the core 46 and the sleeve 48, an electromagnetic coil 54 wound around the bobbin 52 and generating a magnetic circuit by energization, and an electromagnetic coil A cylindrical case 56 provided so as to cover 54 from the outside and also functioning as a yoke, and an end member 58 provided so as to seal the lower end opening of the case 56 are provided. In the present embodiment, the body 5, the core 46, the case 56, and the end member 58 form the body of the entire control valve 1. Between the plunger 50 and the core 46, a spring 47 (functioning as an “urging member”) that biases the plunger 50 in a direction away from the core 46 is interposed.

  The valve body 2 and the solenoid 3 are fixed by press-fitting the lower end of the body 5 into the upper end opening of the core 46. The core 46 has an upper half whose diameter is expanded and extends upward, and the port 16 is provided on the side of the extension. A working chamber 28 is formed between the core 46 and the body 5 to satisfy the suction pressure Ps. On the other hand, the operating rod 38 is inserted so as to penetrate the center of the core 46 in the axial direction. The lower end portion of the operating rod 38 is press-fitted into the upper half of the plunger 50, and the operating rod 38 and the plunger 50 are connected coaxially.

  The operating rod 38 is supported from below by the plunger 50 and is configured to be operatively connected to the main valve body 30, the sub-valve body 36 and the power element 6. The actuating rod 38 transmits a solenoid force, which is a suction force between the core 46 and the plunger 50, on the one hand directly to the sub-valve element 36 and on the other hand to the main valve element 30 via the sub-valve element 36. Further, the driving force due to the expansion / contraction operation of the power element 6 is transmitted to the operating rod 38 via the auxiliary valve body 36. The actuating rod 38 transmits the driving force of the power element 6 to the plunger 50 as a force that opposes the solenoid force.

  A ring-shaped shaft support member 60 is press-fitted into the upper end portion of the core 46, and the operating rod 38 is supported by the shaft support member 60 so as to be slidable in the axial direction. A communication groove (not shown) parallel to the axis is formed at a predetermined location on the outer peripheral surface of the shaft support member 60. The suction pressure Ps introduced / extracted from the port 16 is also guided to the inside of the sleeve 48 through the communication groove, the communication passage 62 formed by the gap between the operating rod 38 and the core 46.

  The communication path 62 functions as an orifice for making the inside of the sleeve 48 an oil damper chamber. That is, in the present embodiment, in the manufacturing process of the control valve 1, oil of the same type as that contained in the refrigerant is lubricated in the sleeve 48 in advance for lubricating the compressor. In the present embodiment, the communication groove provided in the shaft support member 60 functions as a throttle passage that resists oil entering and exiting the sleeve 48. With such a configuration, the sleeve 48 can function as an oil damper chamber, and minute vibrations of the plunger 50 disposed in the sleeve 48 are suppressed. As a result, the generation of noise due to such minute vibration is prevented or suppressed. In the modified example, the communication path 62 may function as a throttle path that resists oil entering and exiting the sleeve 48. That is, at least one of the communication groove and the communication path 62 provided in the shaft support member 60 may function as a throttle path. Note that the spring 47 functions as an off-spring that urges the core 46 and the plunger 50 in a direction to separate them from each other. In the present embodiment, the spring load of the spring 44 is set to be larger than the spring load of the spring 42.

  The sleeve 48 is made of a nonmagnetic material. Plural communicating grooves 66 parallel to the axis are provided on the side surface of the plunger 50, and plural communicating grooves 68 extending in the radial direction and communicating between the inside and the outside are provided on the lower end surface of the plunger 50. With such a configuration, the suction pressure Ps is guided to the back pressure chamber 70 through the gap between the plunger 50 and the sleeve 48 even when the plunger 50 is located at the bottom dead center as shown in the figure.

  A pair of connection terminals 72 connected to the electromagnetic coil 54 extend from the bobbin 52, and extend through the end members 58 to the outside. For convenience of explanation, only one of the pair is displayed in the figure. The end member 58 is attached so as to seal the entire structure in the solenoid 3 included in the case 56 from below. The end member 58 is formed by molding (injection molding) of a resin material having corrosion resistance, and the resin material is also filled in the gap between the case 56 and the electromagnetic coil 54. In this way, the resin material fills the gap between the case 56 and the electromagnetic coil 54 so that the heat generated in the electromagnetic coil 54 can be easily transferred to the case 56 and the heat dissipation performance is enhanced. The end portion of the connection terminal 72 is drawn out from the end member 58 and is connected to an external power source (not shown).

FIG. 2 is a partially enlarged cross-sectional view corresponding to the upper half of FIG.
The body 5 is configured by assembling a first body 81 and a second body 82. The first body 81 has a stepped cylindrical shape, and supports the upper half of the main valve body 30 so as to be slidable by a guide hole 24 formed inside thereof. The second body 82 has a bottomed cylindrical shape and is press-fitted so as to be externally inserted into the lower half of the first body 81. An insertion hole 84 through which a lower part of the main valve body 30 is slidably inserted is provided at the bottom of the second body 82. That is, the main valve body 30 operates stably in the axial direction in such a manner that the upper half is supported by the guide hole 24 and the lower part is supported by the insertion hole 84.

  The main valve body 30 has a stepped cylindrical shape in which the outer diameter of the lower half is slightly reduced, and the reduced diameter portion 85 passes through the insertion hole 84. An internal passage 35 that connects the capacity chamber 22 and the working chamber 28 is formed inside the main valve body 30. On the other hand, the 1st body 81 has the enlarged diameter part 86 by which the internal diameter was expanded a little in the lower part. A pressure chamber 88 is formed by a space surrounded by the enlarged diameter portion 86 of the first body 81, the reduced diameter portion 85 of the main valve body 30, and the second body 82. That is, the pressure chamber 88 is provided on the opposite side of the valve chamber 26 from the capacity chamber 22, and is partitioned from the working chamber 28 by the second body 82. On the other hand, the first body 81 is formed with a communication passage 89 that allows the capacity chamber 22 and the pressure chamber 88 to communicate with each other. As a result, the pressure chamber 88 is always filled with the crank pressure Pc. A tapered step is formed at the proximal end portion of the reduced diameter portion 85 in the main valve body 30, and the tapered surface constitutes the operating surface 87. The operating surface 87 constitutes a mechanism capable of receiving the crank pressure Pc in the pressure chamber 88 and adjusting the pressure receiving balance between the valve body (the main valve body 30 and the sub valve body 36) and the power element 6.

  A labyrinth seal 90 composed of a plurality of annular grooves for suppressing refrigerant flow is provided on the sliding surface of the main valve body 30 with the guide hole 24. A partition wall 92 is provided at an intermediate portion in the axial direction of the main valve body 30. The partition wall 92 functions as an “engaged portion” that can be appropriately engaged and connected to the operating rod 38 on the lower surface thereof. The actuating rod 38 has a stepped columnar shape whose diameter is gradually reduced upward, and passes through an insertion hole provided in the center of the partition wall 92. An engaging portion 94 is formed at the upper end portion of the operating rod 38 by the step of the reduced diameter portion. Around the insertion hole of the partition wall 92, a plurality of through holes 95 for allowing the refrigerant to pass therethrough are formed. Further, when the lower end opening of the reduced diameter portion 85 is attached to and detached from the upper end surface of the core 46, the communication state between the internal passage 35 and the working chamber 28 is blocked or opened. That is, a “shut-off valve portion” that opens and closes the internal passage 35 is configured by the lower end opening of the main valve body 30 and the upper end surface of the core 46.

  A T-shaped communication passage 39 for communicating the internal passage 35 of the main valve body 30 and the capacity chamber 22 is formed in the sub valve body 36. Openings of the communication passage 39 are provided at a plurality of locations on the side surface and the lower surface of the sub valve body 36. The sub-valve body 36 is formed such that the center of the lower end surface thereof is flat, and the operating rod 38 is operatively connected so as to be detachable from below. When the actuating rod 38 is connected to the sub-valve element 36, the upper end surface of the actuating rod 38 contacts the center of the lower end face of the sub-valve element 36 to close the open end of the communication passage 39. That is, the upper end surface of the operating rod 38 and the lower end surface of the sub valve body 36 constitute an “open / close valve portion” that opens and closes the communication passage 39. In the state where the sub-valve element 36 is seated on the sub-valve seat 34, the position of each step of the actuating rod 38 is set so that the engaging portion 94 is separated from the partition wall 92 at a predetermined interval L. Yes. This predetermined interval L functions as so-called “play” (see FIG. 4).

  The spring 42 is interposed between the partition wall 92 and the shaft support member 60. When the solenoid force is increased, the actuating rod 38 can be displaced relative to the main valve body 30, thereby lifting the sub valve body 36 from the sub valve seat 34 and opening the sub valve. Further, the solenoid force can be directly transmitted to the main valve body 30 in a state where the engaging portion 94 and the partition wall 92 are engaged (contacted), and the main valve body 30 is larger than the urging force of the spring 42. Can be pressed in the closing direction of the main valve. This configuration functions as a lock release mechanism that releases the main valve body 30 when the main valve body 30 is locked due to the foreign matter biting into the sliding portion between the main valve body 30 and the guide hole 24. In the present embodiment, the engaging portion 94 of the actuating rod 38 is configured to come into surface contact with and press against the partition wall 92 (the engaged portion). The contact state is not limited to surface contact, but may be line contact or point contact, and it is sufficient that the solenoid force can be directly transmitted to the main valve body 30 by the engagement of both.

  The power element 6 is configured by closing an upper end opening of a bottomed cylindrical bellows 45 by a stopper 74 (corresponding to a “base member”). The stopper 74 is integrally formed with the end member 13. Accordingly, the stopper 74 is fixed to the body 5. The bellows 45 removably contacts the upper end surface of the sub-valve element 36 at the bottom surface. The inside of the bellows 45 is a sealed reference pressure chamber S, and a spring 78 that biases the bellows 45 in the extending direction is interposed between the bottom portion and the stopper 74. The reference pressure chamber S is in a vacuum state in this embodiment.

  Since the spring 78 urges the bottom of the bellows 45 and the stopper 74 in a direction away from each other, the bellows 45 is axially responsive to the differential pressure between the crank pressure Pc of the capacity chamber 22 and the reference pressure of the reference pressure chamber S. It expands or contracts (in the opening and closing direction of the main valve and sub valve). However, if the bellows 45 contracts by a predetermined amount even if the differential pressure increases, the contraction is restricted because the bottom surface of the bellows 45 comes into contact with the lower surface of the stopper 74 and is locked.

  In the above configuration, the main valve body 30 and the main valve seat 20 constitute a main valve, and the flow rate of the refrigerant introduced from the discharge chamber to the crank chamber is adjusted by the opening of the main valve. Further, the auxiliary valve body 36 and the auxiliary valve seat 34 constitute an auxiliary valve, and the opening and closing of the auxiliary valve permits or blocks the refrigerant from the crank chamber to the suction chamber. That is, the control valve 1 also functions as a three-way valve that switches the flow of the refrigerant by opening one of the main valve and the sub valve.

  In the present embodiment, the effective pressure receiving diameter A of the bellows 45 and the effective pressure receiving diameter D of the reduced diameter portion 85 (sliding portion with the insertion hole 84) of the main valve body 30 are set equal. Further, the effective pressure receiving diameter B in the main valve of the main valve body 30 is set equal to the effective pressure receiving diameter C of the main body of the main valve body 30 (sliding portion with the guide hole 24). That is, in the present embodiment, the effective pressure receiving area of the valve body (the valve body when the main valve body 30 and the sub valve body 36 are viewed as one body) is made larger than the effective pressure receiving area of the bellows 45. For this reason, the influence of the crank pressure Pc acting on the valve body in the capacity chamber 22 cannot be completely cancelled.

  Therefore, a pressure chamber 88 is provided on the opposite side of the capacity chamber 22 of the valve chamber 26 so that the operating surface 87 of the main valve body 30 receives the crank pressure Pc, and the effective pressure receiving area of the bellows 45 and the pressure receiving of the operating surface 87 are set. By configuring the combined area and the effective pressure receiving area of the valve body to be the same, the influence of the crank pressure Pc acting on the valve body is canceled. With such a configuration, in the state where the main valve body 30, the sub valve body 36, and the power element 6 are operatively connected, the influence of the discharge pressure Pd and the crank pressure Pc acting on the main valve body 30 is substantially canceled. . As a result, in the main valve control state, the main valve body 30 opens and closes based on the suction pressure Ps that the main valve body 30 receives pressure in the working chamber 28 and the sub-valve body 36 receives in the internal passage 35. Will do. That is, the control valve 1 functions as a so-called Ps sensing valve. In the valve body (the main valve body 30 and the sub-valve body 36), the pressure receiving surface that receives the suction pressure Ps of the working chamber 28 functions as a “pressure sensitive surface”.

  In such a configuration, in a stable control state of the control valve 1, the main valve operates autonomously so that the suction pressure Ps of the working chamber 28 becomes a predetermined set pressure Pset. This set pressure Pset is basically adjusted in advance by the spring load of the springs 42, 44, 47, 78, and is a pressure value that can prevent freezing of the evaporator from the relationship between the temperature in the evaporator and the suction pressure Ps. Is set. The set pressure Pset can be changed by changing the supply current (set current) to the solenoid 3. In this embodiment, the set load of the spring can be finely adjusted by readjusting the press-fitting amount of the end member 13 with the assembly of the control valve 1 substantially completed, and the set pressure Pset is accurately adjusted. be able to.

Next, the operation of the control valve will be described.
3 and 4 are diagrams showing the operation of the control valve, and correspond to FIG. FIG. 2 which has already been described shows the minimum capacity operation state of the control valve. FIG. 3 shows a state when the bleed function of the control valve is operated. FIG. 4 shows a relatively stable control state. In the following, description will be given based on FIG. 1 and with reference to FIGS.

  When the solenoid 3 is not energized in the control valve 1, that is, when the automotive air conditioner is not operating, no suction force acts between the core 46 and the plunger 50. On the other hand, the suction pressure Ps and the crank pressure Pc are relatively high. For this reason, as shown in FIG. 2, the bellows 45 shrinks and the power element 6 does not function substantially. Further, the urging force of the spring 44 is transmitted to the main valve body 30 via the sub-valve body 36, the main valve body 30 is separated from the main valve seat 20, and the main valve is fully opened. At this time, the sub-valve element 36 is seated on the sub-valve seat 34 by the biasing force of the spring 44, and the sub-valve is closed, but the lower end opening of the main valve element 30 is seated on the core 46. The part is closed.

  On the other hand, since the plunger 50 is displaced downward by the urging force of the spring 47, the operating rod 38 is also displaced integrally therewith. As a result, the communication passage 39 of the auxiliary valve body 36 is opened. That is, the on-off valve portion is opened with the shut-off valve portion closed. As a result, the crank pressure Pc is filled in the internal passage 35 of the main valve body 30, and the influence of the crank pressure Pc acting on the main valve body 30 and the sub valve body 36 is cancelled. Thereby, since the differential pressure (Pc−Ps) does not act on the valve body, the main valve body 30 can be driven in the valve closing direction with a small solenoid force when the solenoid 3 is energized next time.

  On the other hand, when a control current is supplied to the electromagnetic coil 54 of the solenoid 3 such as at the time of starting the automobile air conditioner, the actuating rod 38 is driven by the solenoid force. This solenoid force is also transmitted to the main valve body 30 via the actuating rod 38 and the auxiliary valve body 36. As a result, as shown in FIG. 3, the main valve body 30 is seated on the main valve seat 20 to close the main valve, and the sub-valve body 36 is separated from the sub-valve seat 34 together with the closing of the main valve. Open the valve. However, since the displacement of the actuating rod 38 is restricted when the engaging portion 94 is locked to the partition wall 92, the lift amount of the sub-valve element 36 (that is, the opening degree of the sub-valve) is the predetermined value shown in FIG. It matches the interval L. At the time of start-up, the suction pressure Ps and the crank pressure Pc are normally relatively high, so that the bellows 45 is maintained in the contracted state, and the open state of the auxiliary valve is maintained.

  That is, when the starting current is supplied to the solenoid 3, the main valve is closed to restrict the introduction of the refrigerant discharged into the crank chamber, and at the same time, the sub valve is immediately opened to quickly relieve the refrigerant in the crank chamber to the suction chamber. As a result, the compressor can be started quickly. Further, even when the suction pressure Ps is low and the bellows 45 is extended, for example, when the vehicle is placed in a low temperature environment, the auxiliary valve can be opened by supplying a large current to the solenoid 3. And the compressor can be started quickly.

  When the current value supplied to the solenoid 3 is in a control state set to a predetermined value, as shown in FIG. 4, since the suction pressure Ps and the crank pressure Pc are relatively low, the bellows 45 expands and the secondary pressure increases. The valve body 36 is seated on the auxiliary valve seat 34 to close the auxiliary valve. On the other hand, the main valve body 30 operates in such a state that the sub-valve is closed so as to adjust the opening degree of the main valve. At this time, the main valve body 30 operates in accordance with the force in the valve opening direction by the springs 44 and 47, the force in the valve closing direction by the spring 42, the solenoid force in the valve closing direction by the solenoid 3, and the suction pressure Ps. The valve stops at the valve lift position where the force against the solenoid force by the power element 6 is balanced.

  For example, when the refrigeration load increases and the suction pressure Ps becomes higher than the set pressure Pset, the bellows 45 is reduced, so that the main valve body 30 is displaced relatively upward (in the valve closing direction). As a result, the valve opening of the main valve decreases, and the compressor operates to increase the discharge capacity. As a result, the suction pressure Ps changes in a decreasing direction. Conversely, when the refrigeration load is reduced and the suction pressure Ps is lower than the set pressure Pset, the bellows 45 extends. As a result, the urging force by the power element 6 acts in a direction opposite to the solenoid force. As a result, the force in the valve closing direction on the main valve body 30 is reduced, the valve opening of the main valve is increased, and the compressor operates to reduce the discharge capacity. As a result, the suction pressure Ps is maintained at the set pressure Pset.

  When such steady control is being performed, the load on the engine increases, and when it is desired to reduce the load on the air conditioner, the solenoid 3 in the control valve 1 is switched from on to off. Then, since the suction force does not act between the core 46 and the plunger 50, the bellows 45 extends, the main valve body 30 is separated from the main valve seat 20 by the urging force of the spring 44, and the main valve is fully opened. Become. At this time, since the auxiliary valve body 36 is seated on the auxiliary valve seat 34, the auxiliary valve is closed. At this time, the refrigerant having the discharge pressure Pd introduced from the discharge chamber of the compressor to the port 14 passes through the fully opened main valve and flows from the port 12 to the crank chamber. Therefore, the crank pressure Pc is increased and the compressor is operated at the minimum capacity.

  As described above, in the present embodiment, the valve body (main valve body 30, subvalve body 36) receives the crank pressure of the capacity chamber 22 at one end side, and the suction pressure Ps of the working chamber 28 at the other end side. The pressure chamber 88 is provided on the opposite side of the valve chamber 26 from the capacity chamber 22 so that the operating surface 87 of the main valve body 30 receives the pressure. Further, the effect of the crank pressure Pc acting on the valve body is configured by configuring the area obtained by combining the effective pressure receiving area of the bellows 45 and the pressure receiving area of the operating surface 87 to be the same as the effective pressure receiving area of the valve body. Canceled. With such a configuration, even when the valve body needs to be configured to be larger than the bellows 45 as in the present embodiment, the effects of the discharge pressure Pd and the crank pressure Pc are substantial in the control state of the main valve. And can effectively function as a Ps sensing valve. That is, even if the valve body is formed in a desired size, the pressure receiving balance with the power element 6 can be adjusted by adjusting the pressure receiving area of the operating surface 87 accordingly. As a result, the degree of freedom in designing the valve part and the pressure sensitive part can be improved.

[Second Embodiment]
FIG. 5 is a partially enlarged cross-sectional view corresponding to the upper half of the control valve according to the second embodiment. The control valve of the present embodiment is slightly different from the first embodiment in the configuration of the valve body. For this reason, below, it demonstrates centering on difference with 1st Embodiment. In the figure, the same components as those in the first embodiment are denoted by the same reference numerals.

  In the control valve 201, an intermediate chamber 220 (corresponding to “another pressure chamber”) that can communicate with the working chamber 28 is provided between the pressure chamber 88 and the valve chamber 26 in the valve body 202. That is, a communication hole 222 that communicates the inside and the outside is provided in the side portion of the main valve body 230 in the vicinity of the partition wall 92. On the other hand, a concave groove 226 is provided around the inner peripheral surface of the body 205 facing the communication hole 222, that is, an intermediate portion in the axial direction of the guide hole 224. An intermediate chamber 220 is formed between the groove 226 and the main valve body 230. In the present embodiment, the body 205, the core 46, the case 56, and the end member 58 form the body of the entire control valve 201. In this embodiment, the concave groove 226 is provided on the guide hole 224 side, but may be provided on the main valve body 230 side.

  With such a configuration, the intermediate chamber 220 communicates with the internal passage 35 of the main valve body 230. In the control state of the main valve, the lower end opening (shut-off valve portion) of the main valve body 230 is opened, so that the intermediate chamber 220 communicates with the working chamber 28 and thus the port 16. For this reason, even if the high-pressure discharged refrigerant introduced from the port 14 attempts to leak into the guide hole 224, it can be guided to the intermediate chamber 220 and discharged to the working chamber 28 side. That is, the leakage refrigerant can be prevented from entering the pressure chamber 88 and affecting the crank pressure Pc, and the above-described cancel function of the crank pressure Pc can be maintained satisfactorily. Further, since the leakage portion from the discharge chamber to the crank chamber can be only the valve portion of the main valve, the maximum displacement operation can be maintained and the deviation of the suction pressure Ps from the set pressure Pset in the control state can be reduced. . As a result, a stable control state of the main valve can be maintained.

[Third Embodiment]
FIG. 6 is a partially enlarged cross-sectional view corresponding to the upper half of the control valve according to the third embodiment. The control valve of this embodiment is different from the second embodiment in the configuration of the valve body. For this reason, below, it demonstrates centering on difference with 2nd Embodiment. In the figure, the same components as those in the second embodiment are denoted by the same reference numerals.

  The control valve 301 is different from the second embodiment in the pressure receiving mode of the main valve body 330 in the valve main body 302. In addition to the guide hole 224, a guide hole 384 that slidably supports the main valve body 330 is provided in the enlarged diameter portion 86 of the body 305. On the other hand, the outer diameter of the lower end portion of the main valve body 330 is enlarged, and an operating surface 87 is provided at the proximal end portion of the enlarged diameter portion 385. A pressure chamber 88 is formed by a space surrounded by the enlarged diameter portion 86 of the body 305, the main body of the main valve body 330, and the enlarged diameter portion 385 of the main valve body 330. That is, the pressure receiving direction of the operating surface 87 in the main valve body 330 is opposite to that in the second embodiment, and is the valve opening direction of the main valve. The body 305 is formed with a communication path 89 that allows the capacity chamber 22 and the pressure chamber 88 to communicate with each other. A bottomed cylindrical closing member 307 for closing an opening formed when the communication passage 89 is formed is fitted to the lower portion of the body 305. In the present embodiment, the body 305, the core 46, the case 56, and the end member 58 form the body of the entire control valve 301.

  The sub valve body 336 has a valve seat 337 in the middle portion of the communication passage 39. The upper end portion of the operating rod 338 is inserted into the sub-valve element 336 and is attached to and detached from the valve seat 337 to open and close the on-off valve portion. In the power element 306, the bottom of the bellows 45 is sealed with a disk-shaped stopper 308. Although the bottom surface of the stopper 308 is a flat surface, the upper end surface of the sub-valve element 336 has an R shape. For this reason, when the sub-valve element 336 is operatively connected to the power element 306, the sub-valve element 336 and the stopper 308 are almost in point contact. For this reason, even if a lateral load occurs in one of the auxiliary valve body 336 and the power element 306, the lateral load is less likely to act on the other, and the behavior of the valve body is stably maintained. In this embodiment, at the contact portion between the power element 306 and the subvalve body 336, the power element 306 side is a flat surface and the subvalve body 336 side is a curved surface (R shape). The body 336 side may be a flat surface and the power element 306 side may be a curved surface. Alternatively, both the auxiliary valve body 336 side and the power element 306 side may be curved surfaces. In the present embodiment, the body 305, the core 46, the case 56, and the end member 58 form the body of the entire control valve 301.

  In the present embodiment, the effective pressure receiving diameter A of the bellows 45 and the effective pressure receiving diameter D of the enlarged diameter portion 385 (sliding portion with the guide hole 384) of the main valve body 330 are set equal. Further, the effective pressure receiving diameter B in the main valve of the main valve body 330 is set equal to the effective pressure receiving diameter C of the main body of the main valve body 330 (sliding portion with the guide hole 224). That is, in this embodiment, the effective pressure receiving area of the valve body (the valve body when the main valve body 330 and the sub valve body 336 are viewed as one body) is made smaller than the effective pressure receiving area of the bellows 45. For this reason, the influence of the crank pressure Pc acting on the valve body in the capacity chamber 22 cannot be completely cancelled.

  Therefore, the influence of the crank pressure Pc acting on the valve body is canceled by configuring the area obtained by subtracting the pressure receiving area of the operating surface 87 from the effective pressure receiving area of the bellows 45 to be the same as the effective pressure receiving area of the valve body. doing. With such a configuration, in the state where the main valve body 330, the sub valve body 336, and the power element 306 are operatively connected, the influence of the discharge pressure Pd and the crank pressure Pc acting on the main valve body 330 is substantially canceled. . As a result, in the control state of the main valve, the main valve body 330 opens and closes based on the suction pressure Ps received in the working chamber 28. That is, the control valve 301 functions as a so-called Ps sensing valve.

[Fourth Embodiment]
FIG. 7 is a partially enlarged cross-sectional view corresponding to the upper half of the control valve according to the fourth embodiment. The control valve of this embodiment differs from the third embodiment in the configuration of the valve body. For this reason, below, it demonstrates centering on difference with 3rd Embodiment. In the figure, the same components as those in the third embodiment are denoted by the same reference numerals.

  The control valve 401 is different from the third embodiment in the configuration of the auxiliary valve in the valve main body 402. The sub-valve element 436 has a plurality of leg portions 438 provided around the side surface of the stepped cylindrical body at equal intervals. The auxiliary valve body 436 is slidably supported by the body 305 via the leg portions 438. However, the downward displacement of the auxiliary valve body 436 is restricted by the locking portion 19 provided in the body 305. On the other hand, a communication passage 439 that connects the capacity chamber 22 and the main valve hole 18 is formed between the auxiliary valve body 436 and the body 305 by a gap between adjacent leg portions 438.

  On the other hand, a retaining ring 410 is fitted in an intermediate portion of the operating rod 38, and a spring 42 is interposed between the retaining ring 410 and the partition wall 92. A cylindrical locking member 412 is press-fitted into the upper end portion of the operating rod 38. For this reason, the relative movement range of the partition wall 92 is regulated by the engaging portion 94 and the locking member 412. The figure shows a state in which the partition wall 92 abuts on the locking member 412 and the main valve body 330 is positioned at the top dead center relative to the operating rod 38.

  With such a configuration, when the solenoid 3 is not energized, the operating rod 38 is pushed down by the urging force of the spring 47. At this time, the locking member 412 abuts against the partition wall 92 and opens the main valve body 330 in the valve opening direction. Energize to. As a result, as shown in the figure, the main valve is fully opened and the shut-off valve portion is closed. In this embodiment, a gap is formed between the lower surface of the plunger 50 and the bottom surface of the sleeve 48 so that the shut-off valve portion is reliably closed at this time even when the solenoid 3 is turned off. Dimensional configuration.

  Further, at this time, the sub-valve element 436 is urged downward by the urging force of the spring 44, but the displacement of the sub-valve element 436 is restricted by the leg part 438 being engaged with the engaging part 19. Is separated from the main valve body 330 and the auxiliary valve is opened. As a result, the crank pressure Pc is introduced into the internal passage 35 of the main valve body 330 through the communication passage 439. Thereby, the influence of the crank pressure Pc acting on the main valve body 330 and the sub-valve body 336 is cancelled. Thereby, since the differential pressure (Pc−Ps) does not act on the valve body, the main valve body 30 can be driven in the valve closing direction with a small solenoid force when the solenoid 3 is energized next time.

  In addition, if the main valve body 330 is locked due to foreign matter being caught in the sliding portion between the main valve body 330 and the guide hole 224, the solenoid force is increased to resist the biasing force of the spring 42. Thus, the actuating rod 38 can be displaced relative to the main valve body 330. Thereby, when the engaging portion 94 and the partition wall 92 are engaged (contacted), the solenoid force can be directly transmitted to the main valve body 330, and the main valve body 330 is moved by a force larger than the urging force of the spring 42. It can be pressed in the valve closing direction of the main valve. Thereby, the lock | rock of the action | operation rod 38 can be cancelled | released.

[Fifth Embodiment]
FIG. 8 is a partially enlarged cross-sectional view corresponding to the upper half of the control valve according to the fifth embodiment. The control valve of this embodiment is different from the second embodiment in the configuration of the valve body. For this reason, below, it demonstrates centering on difference with 2nd Embodiment. In the figure, the same components as those in the second embodiment are denoted by the same reference numerals.

  The control valve 501 is different from the second embodiment in the configuration of the main valve and the sub valve in the valve main body 502. In the main valve body 530, the length of the reduced diameter portion 85 is slightly shortened, while the main valve body 530 is biased in the valve closing direction by the spring 42, so that the lower end opening does not sit on the core 46 even when the main valve body 530 is fully opened. . That is, in this embodiment, the shut-off valve portion is not configured. On the other hand, the auxiliary valve body 536 has a stepped cylindrical shape and is press-fitted and fixed to the upper end portion of the operating rod 38. For this reason, the spring which urges | biases the subvalve body 536 directly in the valve closing direction of a subvalve is not provided. The sub valve body 536 is not provided with a communication path. A retaining ring 410 is fitted in an intermediate portion of the operating rod 38, and a spring 42 is interposed between the retaining ring 410 and the partition wall 92.

  With such a configuration, as in the second embodiment, the influence of the crank pressure Pc is canceled in the control state of the main valve, but the valve bodies (the main valve body 530 and the sub-valve body 536 when the main valve is fully opened). ) Acts on the differential pressure (Pc−Ps). For this reason, when starting the solenoid 3, the valve body must be driven against the force caused by the differential pressure (Pc-Ps). However, before the solenoid 3 is started, normally there is almost no difference in pressure between the crank pressure Pc and the suction pressure Ps. On the other hand, by comprising in this way, the number of springs can be reduced and a subvalve can be constituted comparatively simply. There is also an advantage that the overall length of the control valve can be reduced.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the specific embodiments, and various modifications can be made within the scope of the technical idea of the present invention. Absent.

  In each of the above embodiments, a so-called Ps sensing valve that operates by sensing the suction pressure Ps is shown as the control valve. However, it may be configured as a so-called Pc sensing valve that operates by sensing the crank pressure Pc. In that case, the port 16 is communicated with the crank chamber.

  Although the example which employ | adopts the bellows 45 as a pressure sensitive member which comprises the power elements 6 and 306 was shown in the said embodiment, you may employ | adopt a diaphragm. In this case, a plurality of diaphragms may be connected in the axial direction in order to ensure an operation stroke necessary for the pressure sensitive member.

  In each of the above embodiments, an example in which a single port 12 is provided as a crank chamber communication port (introduction / exit port) communicating with the crank chamber has been described. In the modification, the crank chamber communication port includes a first port (derivation port) for leading the refrigerant in the capacity chamber 22 to the crank chamber, and a second port (introduction port) for introducing the refrigerant in the crank chamber to the capacity chamber 22. You may divide and comprise.

  In the above-described embodiment, the spring (coil spring) is exemplified as the biasing member with respect to the springs 42, 44, 47, 78 and the like. However, an elastic material such as rubber or resin, or an elastic mechanism such as a leaf spring may be employed. Needless to say, it is good.

  In the above embodiment, a control valve for so-called closing control that adjusts the flow rate or pressure of the refrigerant introduced from the discharge chamber of the variable capacity compressor to the crank chamber has been shown. However, in a modified example, the control valve is led out from the crank chamber to the suction chamber. You may comprise as a control valve of what is called extraction control which adjusts the flow volume or pressure of the refrigerant | coolant to perform.

  In addition, this invention is not limited to the said embodiment and modification, A component can be deform | transformed and embodied in the range which does not deviate from a summary. Various inventions may be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments and modifications. Moreover, you may delete some components from all the components shown by the said embodiment and modification.

  DESCRIPTION OF SYMBOLS 1 Control valve, 2 Valve body, 3 Solenoid, 5 Body, 6 Power element, 20 Main valve seat, 22 Capacity chamber, 26 Valve chamber, 28 Actuation chamber, 30 Main valve body, 34 Sub valve seat, 36 Sub valve body, 38 Acting rod, 45 Bellows, 87 Working surface, 88 Pressure chamber, 92 Bulkhead, 94 Engaging part, 201 Control valve, 202 Valve body, 205 Body, 220 Intermediate chamber, 230 Main valve body, 301 Control valve, 302 Valve body , 305 Body, 306 Power element, 330 Main valve body, 336 Sub valve body, 337 Valve seat, 338 Actuating rod, 401 Control valve, 402 Valve body, 436 Sub valve body, 501 Control valve, 530 Main valve body, 536 Sub valve Valve body.

Claims (10)

At least of the refrigerant introduced into the crank chamber from the discharge chamber and the refrigerant led out from the crank chamber to the suction chamber, the discharge capacity of the variable capacity compressor that compresses the refrigerant introduced into the suction chamber and discharges it from the discharge chamber In a control valve for a variable capacity compressor that is changed by adjusting one flow rate or pressure,
A body having a capacity chamber communicating with the crank chamber from one end side, a valve chamber communicating with the discharge chamber, and a working chamber into which a sensed pressure is introduced;
The body is slidably supported, receives the crank pressure in the capacity chamber at one end side, receives the sensed pressure in the working chamber at the other end side, and connects the valve chamber and the capacity chamber. A valve body that opens and closes a valve part by attaching and detaching to a valve seat provided therebetween;
A pressure sensing unit that senses the crank pressure in the capacity chamber and biases the valve body in a valve opening direction according to the crank pressure;
With
A pressure chamber into which the crank pressure of the capacity chamber is introduced is formed on the side opposite to the capacity chamber with respect to the valve chamber,
The control valve for a variable capacity compressor, wherein the valve body is provided with an operating surface for receiving a crank pressure in the pressure chamber. The effective pressure receiving area of the valve body is larger than the effective pressure receiving area of the pressure sensitive part,
The effective pressure receiving area of the valve body is configured to be equal to or substantially equal to an area obtained by combining the effective pressure receiving area of the pressure sensing portion and the pressure receiving area of the working surface. Control valve for variable capacity compressor. The effective pressure receiving area of the valve body is smaller than the effective pressure receiving area of the pressure sensing portion,
The effective pressure receiving area of the valve body is configured to be equal to or substantially equal to an area obtained by subtracting the pressure receiving area of the working surface from the effective pressure receiving area of the pressure sensing unit. Control valve for variable capacity compressor.   The effective pressure-receiving area of the pressure-sensitive surface that receives the pressure sensed in the working chamber in the valve body is configured to be the same as or substantially equal to the effective pressure-receiving area of the pressure-sensitive part. 4. A control valve for a variable capacity compressor according to 3.   The control valve for a variable capacity compressor according to any one of claims 1 to 4, wherein another pressure chamber capable of communicating with the working chamber is provided between the pressure chamber and the valve chamber. As the valve body, there is an internal passage for connecting the capacity chamber and the working chamber while opening and closing the main valve by attaching to and detaching from the main valve seat provided in the main passage for communicating the valve chamber and the capacity chamber. The formed main valve body,
A sub-valve element that opens and closes the sub-valve by attaching / detaching to / from the sub-valve seat provided inside or at the end of the internal passage;
The control valve for a variable capacity compressor according to claim 1, comprising: A solenoid that generates a solenoid force having a magnitude corresponding to the amount of current supplied;
An operating rod connected to the solenoid and capable of transmitting a solenoid force in a valve closing direction directly or indirectly to the valve body;
Further comprising
The actuating rod is configured to transmit a solenoid force in a valve opening direction of the sub valve to the sub valve body,
The variable capacity compressor according to claim 6, further comprising a shutoff valve portion that shuts off communication between the internal passage and the working chamber when the main valve is fully opened when the solenoid is turned off. Control valve. A communication passage that connects the capacity chamber and the internal passage to the sub valve body is formed,
The open / close valve portion is further provided to shut off the communication path when the solenoid is turned on and open the communication path when the solenoid is turned off. A control valve for a variable capacity compressor described in 1. The sub-valve element is provided between the main valve element and the pressure-sensitive part, and the sub-valve element and the pressure-sensitive part are configured to be able to contact and separate.
The control for a variable capacity compressor according to any one of claims 6 to 8, wherein at least one contact surface between the sub-valve element and the pressure-sensitive portion is formed in an R shape. valve. A solenoid that generates a solenoid force having a magnitude corresponding to the amount of current supplied;
An operating rod connected to the solenoid and capable of transmitting a solenoid force in a valve closing direction directly or indirectly to the valve body;
The control valve for a variable capacity compressor according to any one of claims 1 to 6, further comprising:

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