Capacity control valve

Abstract

In an embodiment, a capacity control valve includes: a pressure-sensitive body 50 positioned in a third valve chamber 38; an adapter 53 provided on the free end of the pressure-sensitive body 50 having a circular seating surface; a third valve part 43 that moves integrally with a valve element 40 in the third valve chamber 38 and has a circular engagement surface that opens/closes intake-side passages 34 by engaging with and separating from the seating surface of the adapter 53; and a solenoid 60 that applies an electromagnetic drive force to the valve element 40 in the direction of closing a first valve part 41, wherein the pressure-sensitive body 50 is formed by a formed bellows made of material having greater yield stress than phosphor bronze, and the formed bellows has its diameter set smaller and its stroke longer than the diameter and stroke of a phosphor bronze bellows.

Description

TECHNICAL FIELD[0001]The present invention relates to a capacity control valve that variably controls the capacity or pressure of working fluid, and specifically to a capacity control valve that controls the discharge rate of a variable-capacity compressor, etc., used for an automobile air-conditioning system, etc., according to the pressure load.BACKGROUND ART[0002]A swashplate type variable-capacity compressor used for an automobile air-conditioning system, etc., comprises, for example, a rotational axis driven by the rotational force of an engine to turn; a swashplate connected to the rotational axis in a manner allowing for change in its inclination angle relative to the rotational axis; and a compression piston connected to the swashplate, wherein the inclination angle of the swashplate is changed to change the stroke of the piston and thereby control the discharge rate of refrigerant gas.[0003]This inclination angle of the swashplate is continuously changed by utilizing the in...

AI Technical Summary

Benefits of technology

[0049]The present invention has excellent effects as described below:

[0050](1) The pressure-sensitive body is formed by a formed bellows made of material having greater yield stress than phosphor bronze, and the formed bellows has its diameter set smaller and its stroke longer than the diameter and stroke of a phosphor bronze bellows, and therefore the diameter of the bellows and that of the valve element can be reduced and response of the valve element can be improved and also the diameter of the valve body can be reduced. Furthermore, the diameter of the capacity control valve containing the solenoid can be reduced and consequently the capacity control valve can be made lighter and more space-saving. Eventually, such capacity control valve can contribute to the size reduction and weight reduction of a swashplate-type variable-capacity compressor and weight reduction of a vehicle, thus helping provide environmentally friendly products. Additionally, a smaller bellows diameter leads to a smaller adapter diameter, which in turn improves the vibration resistance of the bellows and also improves the vibration resistances of other movable parts as a result of reduced weights of the parts due to diameter reduction. All these reductions can ultimately contribute to improved durability.

[0051](2) The pre...

Problems solved by technology

This bellows 78A is made of phosphor bronze to achieve good workability, but from the viewpoint of spring property, phosphor bronze has a small yield stress as a material itself and cannot ensure a long stroke, and also a bellows made of phosphor bronze tends to undergo characteristic changes such as drop in load when an excessive pressure is applied or during use at high temperature, which makes it impossible to reduce the diameter or eliminate the coil spring ...

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