Patent ID: 9651037
Date: 2017-05-16
CPC Classifications: F04B,F25B,Y10T

Claim:
1. A control valve for a variable displacement compressor for varying a discharging capacity of the variable displacement compressor by controlling a flow rate of refrigerant to be introduced from a discharge chamber of the compressor to a crankcase of the compressor, the control valve comprising: a body having a discharge pressure chamber that communicates with the discharge chamber, a crank pressure chamber that communicates with the crankcase, a valve hole provided in a passage joining the discharge pressure chamber to the crank pressure chamber, and a guiding passage formed coaxially with the valve hole; an actuating rod slidably supported along the guiding passage, the actuating rod having a valve element configured to open and close a valve section such that the valve element touches and leaves the valve hole; a solenoid configured to apply force in an opening or closing direction of the valve section to the valve element via the actuating rod; and a seal section provided between the actuating rod and the guiding passage, the seal section containing a sealing member therein where the sealing member serves to restrict leakage of the refrigerant from a high pressure side to a low pressure side, wherein the seal section is an annular recessed groove formed in either one of an inner surface of the guiding passage into which the actuating rod is inserted and an outer surface of the actuating rod that is inserted into the guiding passage, wherein the sealing member is an annular member fitted in the recessed groove in such a manner that the sealing member is supported by either one of the body and the actuating rod and is in contact with and slidable relative to an other one of the body and the actuating rod, wherein the recessed groove has a width in an axial direction larger than a width in the axial direction of a cross section of the sealing member, so that a space is present between a higher-pressure-side surface of the recessed groove and the sealing member, wherein the actuating rod and the guiding passage are configured such that a clearance, between the actuating rod and the guiding passage, which is at a higher-pressure side adjacent the recessed groove is larger than a clearance therebetween which is at a lower-pressure side adjacent the recessed groove, and wherein a clearance length in the axial direction on the higher-pressure side of the recessed groove is shorter than a clearance length in the axial direction on the lower-pressure side of the recessed groove.