Fluid pressure responsive apparatus

摘要

A differential pressure unit having overrange valves loosely mounted on a valve stem connected between the ends of a respective pair of movable bellows ends. A pair of spiral range springs bias both valves toward open positions. The valves include annular elastomers bonded to the edges of the apertured discs. The apertures in the discs act to allow the elastomers to seat and to unseat without causing lock-up. The discs are retained between plates and snap rings.