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EP-4219994-B1 - VALVE

EP4219994B1EP 4219994 B1EP4219994 B1EP 4219994B1EP-4219994-B1

Inventors

  • KURIHARA, DAICHI
  • HASHIGUCHI, AKIHIRO
  • FUKUDOME, KOHEI
  • SHIRAFUJI, KEIGO

Dates

Publication Date
20260506
Application Date
20210924

Claims (9)

  1. A valve (V1, V2), comprising: a valve housing (10) having a primary pressure space (S1) and a secondary pressure space (S2); a valve seat (40a) disposed between the primary pressure space (S1) and the secondary pressure space (S2); a valve body (56) that is driven in an axial direction by a driving source (80) to be seated on or separate from the valve seat (40a); characterized by a communication passage (15, 150) that provides communication between a back space (S3) adjacent to one of the primary pressure space (S1) and the secondary pressure space (S2) and remaining one of the primary pressure space (S1) and the secondary pressure space (S2), wherein a partition member (30, 300) that is expandable and contractible in the axial direction is disposed between the valve housing (10) and the valve body (56), and the back space (S3) and the one of the primary pressure space (S1) and the secondary pressure space (S2) are partitioned off from each other in a sealed state by the partition member (30, 300).
  2. The valve (V1, V2) according to claim 1, wherein a first biasing member (14) that biases the valve body (56) in a valve closing direction and a second biasing member (85) that biases the valve body (56) in a valve opening direction are disposed to face each other.
  3. The valve (V1, V2) according to claim 2, wherein the first biasing member (14) is a coil spring, and the valve body (56) is provided with a fitting portion fitted to the coil spring in the axial direction.
  4. The valve (V1, V2) according to any one of claims 1 to 3, wherein the partition member (30, 300) includes a ring portion (33) fixed to the valve housing (10), and a body portion (31) having an accordion shape of which one end is fixed to the ring portion (33) in a sealed state.
  5. The valve (V1, V2) according to claim 4, wherein an outer peripheral surface of the ring portion (33) is fixed to an inner peripheral surface of the valve housing (10).
  6. The valve (V1, V2) according to claims 4 or 5, wherein an inner peripheral surface of the ring portion (33) serves as a tilt restriction portion of the valve body (56).
  7. The valve (V1, V2) according to any one of claims 4 to 6, wherein the body portion (31) extends from the ring portion (33) to the one of the primary pressure space (S1) and the secondary pressure space (S2).
  8. The valve (V1, V2) according to any one of claims 1 to 7, wherein the valve body (56) includes a valve element (51, 510) to be seated on the valve seat (40a) and a rod element (20, 200) to be driven by the driving source (80) as separate bodies.
  9. The valve (V1, V2) according to claim 8, wherein the partition member (30, 300) includes a fixation plate portion (32) fixed to an end surface of the rod element (20, 200), and a body portion (31) having an accordion shape of which one end is fixed to the fixation plate portion (32) in a sealed state, and one of the valve body (56) and the fixation plate portion (32) includes a guide recessed portion (34) that guides remaining one of the valve body (56) and the fixation plate portion (32) in a direction toward an axial center.

Description

{TECHNICAL FIELD} The present invention relates to a valve that controls a working fluid. {BACKGROUND ART} A valve used to control a working fluid in various industrial fields includes a valve seat and a valve body that can come into contact with and separate from the valve seat, and can control the pressure or flow rate of the working fluid by adjusting a valve opening degree. Examples of representative valve forms of such a valve include a spool valve in which a spool that a valve body moves parallel to an opening that is a valve seat, a butterfly valve in which a valve body includes a rotating shaft, and a lift valve in which a valve body moves orthogonally to an opening that is a valve seat. Among these valves, the lift valve is the most suitable for controlling the flow rate or pressure. Examples of the lift valve include a capacity control valve of a variable displacement compressor used for an air conditioning system of an automobile or the like. The variable displacement compressor includes a rotating shaft to be rotationally driven by an engine, a swash plate coupled to the rotating shaft such that a tilt angle is variable, compressing pistons coupled to the swash plate, and the like, and by changing the tilt angle of the swash plate, changes a stroke amount of the pistons to control a discharge amount of fluid. This tilt angle of the swash plate can be continuously changed by appropriately controlling pressure in a control chamber while using a suction pressure Ps of a suction chamber that suctions the fluid, a discharge pressure Pd of a discharge chamber that discharges the fluid pressurized by the pistons, and a control pressure Pc of the control chamber that houses the swash plate, by means of the capacity control valve to be driven to open and close by electromagnetic force. A capacity control valve of Patent Citation 1 includes a valve housing, a valve seat, and a valve body. In the valve housing, a primary pressure space through which a control fluid of the control pressure Pc passes and a secondary pressure space through which the control fluid of the suction pressure Ps passes are formed. The valve seat is provided between the primary pressure space and the secondary pressure space. The valve body is configured such that a valve contact portion is provided in the primary pressure space and a rod portion is provided in a back space on a solenoid side, and can come into contact with and separate from the valve seat. The capacity control valve of Patent Citation 1 adjusts the control pressure Pc of the control chamber by moving the valve body using electromagnetic force generated in a solenoid. In addition, a communication passage that provides communication between the secondary pressure space and the back space is formed in the valve housing. According to this configuration, the secondary pressure space and the back space are allowed to have the same pressure by the communication passage, and no pressure difference occurs between both sides of the valve body in an axial direction. For this reason, precise control of a rod can be performed according to an electric current applied to the solenoid. {CITATION LIST} {Patent Literature} Patent Citation 1: WO 2020/110925 A (PAGE 10 and FIG. 3) {SUMMARY OF INVENTION} {Technical Problem} In the capacity control valve of Patent Citation 1, the rod portion of the valve body is inserted into a guide hole provided between the primary pressure space and the back space in the valve housing, and the rod portion is guided by the guide hole to stably slide. However, since a very small gap is formed between an outer peripheral surface of the rod portion and an inner peripheral surface of the guide hole, the control pressure Pc of the primary pressure space slightly leaks to the back space from the gap between the outer peripheral surface of the rod portion and the guide hole, and the control pressure Pc of the primary pressure space cannot be controlled with high accuracy, which is a problem. The present invention is conceived in view of such a problem, and an object of the present invention is to provide a valve capable of controlling a fluid with high accuracy. {Solution to Problem} In order to solve the foregoing problem, a valve according to the present invention includes: a valve housing having a primary pressure space and a secondary pressure space; a valve seat disposed between the primary pressure space and the secondary pressure space; a valve body that is driven in an axial direction by a driving source to be seated on or separate from the valve seat; and a communication passage that provides communication between a back space adjacent to one of the primary pressure space and the secondary pressure space and remaining one of the primary pressure space and the secondary pressure space, wherein a partition member that is expandable and contractible in the axial direction is disposed between the valve housing and the valve body, and the back space and