| 摘要 |
A force-balanced gas control valve assembly having an integral cylindrical actuator housing and tubular valve body. A mounting flange attached to the housing has a central aperture through which the valve body projects. An annular valve seat is provided in the valve body. A pintle shaft within the valve body has a valve head matable with the valve seat, a force-balancing piston, an interstem separating the valve head from the piston, and an armature extending into a solenoid actuator subassembly disposed within the actuator housing. The pintle is formed of a ferromagnetic material such as a magnetic stainless steel. In a flow chamber within the valve body, pressure is exerted equally on both the piston, in a direction tending to open the valve, and the valve head, in a direction tending to close the valve. Thus the valve is force-balanced, and the solenoid need operate against only the frictional forces within the valve itself. Preferably, the valve assembly includes a low-friction composite guiding sleeve between the armature and the polepieces of the solenoid. <IMAGE> |
