A capacity control valve includes: a pressure-sensitive body positioned in a third valve chamber; an adapter provided on the free end of the pressure sensitive body having a circular seating surface; a third valve part that moves integrally with a valve element in the third valve chamber and has a circular engagement surface that opens/closes intake-side passages by engaging with and separating from the seating surface of the adapter. The valve element is located between the first valve chamber and the second valve chamber, and has an outer circumferential face part slidably movable relative to an inner circumferential face of the valve body, with plural threads of screw grooves are formed on the outer circumferential face part.

A capacity control valve includes: a pressure-sensitive body positioned in a third valve chamber; an adapter provided on the free end of the pressure sensitive body having a circular seating surface; a third valve part that moves integrally with a valve element in the third valve chamber and has a circular engagement surface that opens/closes intake-side passages by engaging with and separating from the seating surface of the adapter; and a solenoid that applies an electromagnetic drive force to the valve element in the direction of closing a first valve part, wherein 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.

A vacuum valve is provided with opening pressure setting means that sets a set value of a fluid pressure in a primary side passage beyond which communication is opened and forcible opening means that forcibly opens communication regardless of the fluid pressure in the primary side passage. The opening pressure setting means includes a spring receiver fixed to a stem, a compression coil spring having a lower end supported by the spring receiver, and an adjustment screw, movable in the axial direction, that presses the upper end of the compression coil spring. The forcible opening means includes a piston inserted onto the stem 5 under the spring receiver so as to be movable upward and downward and piston driving means that moves the piston and the spring receiver upward integrally by moving the piston upward using compressed air.

A pressure regulator for compressed gas, comprising a body with a gas inlet, a gas outlet and a gas passage interconnecting said gas inlet with said gas outlet; a shut-off device comprising a seat located in the gas passage; a shutter configured for cooperating the seat; a pressure sensing assembly defining an internal volume filled with an auxiliary gas and closed by a plug, said pressure sensing assembly being elastically deformable and located in the gas passage downstream of the seat, said pressure sensing assembly being configured for actuating the shutter relative to the seat depending on a gas pressure downstream of the seat; a port fluidly connected, via the plug, to the internal volume, and configured for fluidly connecting an external source of the auxiliary gas to said internal volume for adjusting a pressure of the auxiliary gas in said internal volume.

A pressure regulator for compressed gas, comprising a body with a gas inlet, a gas outlet and a gas passage interconnecting said gas inlet with said gas outlet; a shut-off device comprising a seat located in the gas passage; a shutter configured for cooperating the seat; a pressure sensing assembly defining an internal volume filled with an auxiliary gas and closed by a plug, said pressure sensing assembly being elastically deformable and located in the gas passage downstream of the seat, said pressure sensing assembly being configured for actuating the shutter relative to the seat depending on a gas pressure downstream of the seat; a port fluidly connected, via the plug, to the internal volume, and configured for fluidly connecting an external source of the auxiliary gas to said internal volume for adjusting a pressure of the auxiliary gas in said internal volume.