Valve device for a bellows type gas meter uses ceramic and thermoplastic materials to reduce material and machining costs, while providing acceptable long-term stability

摘要

Valve device for a bellows type gas meter has a slider grating (18), a grating element (24) and slider element (26) of the slider (20) all made of ceramic material. The slider element (26) has sliding surfaces (30) in close contact with sliding surfaces (28) of the grating element (24). Optionally the slider grating and the slider can be made from low-cost thermoplastic material.