초록 ▼

A gas cylinder valve for high pressure gas cylinders includes a pneumatic actuator with tandem pistons which are operated by normal industry “house”pneumatic pressures to overcome the large closing bias force generated by a set of disc springs so that the valve opening spring can lift the valve stem

A gas cylinder valve for high pressure gas cylinders includes a pneumatic actuator with tandem pistons which are operated by normal industry “house”pneumatic pressures to overcome the large closing bias force generated by a set of disc springs so that the valve opening spring can lift the valve stem from its seat. A floating pressure plate which seats against an annular internal shoulder in the actuator housing prevents pneumatic pressure applied to the upper piston from acting on the back of the lower piston. Pneumatic pressure from a common source is applied to both pistons through an axial hole in a piston rod integral with one piston and bearing against the other piston. The actuator is easily assembled by merely inserting the lower piston, the pressure plate, the upper piston and the disc springs into the open end of a cup-shaped housing, and securing them in place with a preload on the springs by screwing on a housing cover.

대표청구항 ▼

A pneumatic actuator for a cylinder valve having a valve stem member which is biased away from a valve seat by a first spring to open the valve, said actuator comprising: a hollow cylindrical housing having an end wall at one end thereof; connection means secured to the end wall of the actuator hous

A pneumatic actuator for a cylinder valve having a valve stem member which is biased away from a valve seat by a first spring to open the valve, said actuator comprising: a hollow cylindrical housing having an end wall at one end thereof; connection means secured to the end wall of the actuator housing mounting said actuator on the cylinder valve, said connection means and end wall defining an aperture through which said valve stem member extends; a first piston slidable in the actuator housing and forming with said end wall a first actuator chamber; a second piston slidable in said actuator housing with the first piston between the second piston and said end wall; a pressure plate in said cylindrical housing between the first and second pistons forming with the second piston a second actuator chamber and fixing the boundary of the second actuator chamber relative to the end wall; biasing means generating a biasing force biasing said second piston toward said end wall; means extending through the pressure plate transmitting the biasing force applied to the second piston to the first piston biasing said first piston against the valve stem member and closing said valve stem against an opening force generated by said first spring; and means introducing pressurized fluid into one of said actuator chambers, said means extending through said pressure plate defining a passage interconnecting said first and second actuator chambers such that the pressurized fluid is introduced into both actuator chambers exerting a force against both pistons and generating a combined force overcoming said biasing force of the biasing means whereby said first spring opens said valve.