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EP-3951175-B1 - CAPACITY CONTROL VALVE

EP3951175B1EP 3951175 B1EP3951175 B1EP 3951175B1EP-3951175-B1

Inventors

  • HAYAMA, MASAHIRO
  • FUKUDOME, KOHEI
  • Kanzaki, Toshinori
  • TAKAHASHI, WATARU
  • SHIRAFUJI, KEIGO

Dates

Publication Date
20260506
Application Date
20200402

Claims (7)

  1. A capacity control valve (V) comprising: a valve housing (210, 310) provided with a suction port (11, 211) through which a suction fluid of suction pressure (Ps) passes, and a control port (12, 212) through which a control fluid of control pressure (Pc) passes; a valve element ( 251, 351) configured to be driven by a solenoid (80); a spring (385) that biases the valve element ( 251, 351) in a direction opposite to a driving direction of the solenoid (80); and a CS valve formed by a CS valve seat 210a, 310a) and the valve element ( 251, 351) and configured to open and close a communication between the control port (12, 212) and the suction port (11, 211)in accordance with a movement of the valve element ( 251, 351), wherein the control pressure (Pc) is controlled by opening and closing the CS valve and the control fluid is introduced into a back surface side of the valve element (251, 351), wherein the control port (12, 212) is formed by a recessed portion in which the radially inner side of an axially one end of the valve housing (210, 310) is recessed to the axially other end side, and also serves as a control fluid supply chamber (230) to which the control fluid of control pressure (Pc) is supplied, the suction port (11, 211) extends in the radially inward direction from an outer peripheral surface of the valve housing (210, 310) and communicates with a valve chamber (20, 220) in which an axially one end portion of the valve element ( 251, 351) is arranged reciprocatably in the axial direction, the valve chamber (20, 220) communicates with the control fluid supply chamber (230) via a through hole (210d) formed on an inner peripheral surface of the valve housing (210, 310), on the inner peripheral surface of the valve housing ( 210, 310), the CS valve seat 210a, 310a) is formed at an opening end edge of the through hole (210d) on the valve chamber (20, 220) side, the CS valve seat (210a, 310a) and a guide hole (210b, 310b) into which the valve element ( 251, 351) is inserted are formed in the valve housing (210, 310), and the valve element ( 251, 351) is a pillar-shaped body in which an annular groove (251b, 351b) is formed on an outer peripheral surface to slide with an inner peripheral surface of the guide hole (210b, 310b) of the valve housing (210, 310).
  2. The capacity control valve (V) according to claim 1, wherein the CS valve seat (210a, 310a) and the guide hole (210b, 310b) are provided in one member element which partially forms the valve housing (210, 310).
  3. The capacity control valve (V) according to claim 1 or 2, wherein the valve element is a pillar-shaped body having a constant cross section.
  4. The capacity control valve (V) according to any one of claims 1 to 3, wherein the valve element (251, 351) also serves as a rod arranged to pass through a coil of the solenoid (80).
  5. The capacity control valve (V) according to any one of claims 1 to 4, wherein the direction in which the valve element ( 251, 351) is biased by the spring ( 385) is a valve opening direction of the CS valve.
  6. The capacity control valve (V) according to any one of claims 1 to 5, wherein the control fluid from the control port (212) is introduced into a first end side of the valve element (251) opposed to the back surface side, and the control fluid from the control port (212) is introduced, via a supply passage (213) formed in the valve housing (210), into a second end side of the valve element (251) as the back surface side.
  7. The capacity control valve (V) according to any one of claims 1 to 5, wherein the control fluid from the control port (12) is introduced into a first end side of the valve element (351) opposed to the back surface side, and the control fluid from the control port (12) is introduced, via a supply passage (313) formed in the valve element (351), into a second end side of the valve element (351) as the back surface side.

Description

{TECHNICAL FIELD} The present invention relates to a capacity control valve that variably controls capacity of a working fluid, for example, a capacity control valve that controls a discharge amount of a variable displacement compressor used for an air conditioning system of an automobile in accordance with pressure. {BACKGROUND ART} A variable displacement compressor used for an air conditioning system of an automobile, etc. includes a rotating shaft to be driven and rotated by an engine, a swash plate coupled to the rotating shaft in such a manner that a tilt angle is variable, compressing pistons coupled to the swash plate, etc., and by changing the tilt angle of the swash plate, changes a stroke amount of the pistons to control a discharge amount of a fluid. This tilt angle of the swash plate can be continuously changed by appropriately controlling pressure in a control chamber while utilizing suction pressure Ps of a suction chamber that suctions the fluid, discharge pressure Pd of a discharge chamber that discharges the fluid pressurized by the pistons, and control pressure Pc of the control chamber that houses the swash plate, with using a capacity control valve to be driven to open and close by electromagnetic force. At the time of continuously driving the variable displacement compressor, the capacity control valve performs normal control in which energization is controlled by a control computer, a valve element is moved in the axial direction by electromagnetic force generated in a solenoid, and a DC valve provided between a discharge port through which a discharge fluid of the discharge pressure Pd passes and a control port through which a control fluid of the control pressure Pc passes is opened and closed to adjust the control pressure Pc of the control chamber of the variable displacement compressor. At the time of normal control of the capacity control valve, the pressure of the control chamber in the variable displacement compressor is appropriately controlled, and by continuously changing the tilt angle of the swash plate with respect to the rotating shaft, the stroke amount of the pistons is changed to control the discharge amount of the fluid to the discharge chamber. Thus, the air conditioning system is adjusted to have a desired cooling ability. In the capacity control valve of Patent Citation 1, by opening and closing the DC valve to control the fluid of the discharge pressure Pd supplied to the control chamber of the variable displacement compressor and bringing a pressure difference between the discharge pressure Pd of the discharge chamber and the control pressure Pc of the control chamber respectively applied in the stroke direction of the pistons close to a target value, the discharge amount of the fluid discharged from the discharge chamber is changed. A valve opening degree of the DC valve is changed in accordance with the electromagnetic force by an electric current applied to the solenoid, and in response to this, the target value of the pressure difference is changed, so that the discharge amount of the fluid discharged from the discharge chamber is changed. In Patent Citation 1, by Pd-Pc control that makes adjustment in such a manner that the fluid of the discharge pressure Pd is supplied to the control chamber to increase the control pressure Pc, it is possible to promptly perform pressure adjustment. However, in order to perform more precise pressure adjustment, a pressure sensitive body having a bellows is provided in a pressure sensitive chamber of the capacity control valve, and by extending and contracting the pressure sensitive body in the moving direction of the valve element in accordance with the suction pressure Ps, bias force is applied in the valve opening direction of the valve element, and the valve opening degree of the DC valve is adjusted. In such a way, by adjusting the valve opening degree of the DC valve by the pressure sensitive body that senses the suction pressure Ps with respect to fixed electromagnetic force in accordance with the electric current applied to the solenoid, the control pressure Pc is finely adjusted additionally taking the suction pressure Ps in consideration, and precision for controlling the discharge amount of the fluid discharged from the discharge chamber is enhanced. In Patent Citation 2 an electromagnetic control valve of a fast response compression volume control apparatus for a refrigeration cycle is described which connects and blocks a crank chamber of the compressor to and from a discharge chamber such that the differential pressure between the crank chamber and the suction chamber is maintained at a predetermined value. The differential pressure is changed by changing the electromagnetic force of the electromagnetic control valve such that the discharge volume of the refrigerant is controlled and the compression volume becomes a predetermined one in a prompt action without a time delay when the electromagnetic force is va