Diaphragm apparatus having a magnetically imparted hysteresis characteristic

摘要

In a diaphragm apparatus, such as a switch having a diaphragm to be driven by a pressure difference between two spaces, an iron disk is fixed to the center of the diaphragm and a ring-shaped permanent magnet is fixed to an inside wall of a case to magnetically attract the iron disk. This provides hysteresis in the force-motion characteristic of the diaphragm to reduce hunting.