Thermostatic on=off gas control valve

摘要

An electrical switch (76) which indicates the position of the valve is mounted on the outside of the valve housing (12). The switch is operated by a magnetic field produced by a permanent magnet (72) attached to the pivoted arm (64) of a snap-action switch. The magnet is pref. inserted in a plastics case (74) which is located in a cut-out (70) in the edge of the pivoted arm. The parts of the snap-action switch are pref. arranged and dimensioned so that when an actuating lever pivots the arm travels through a larger pivot angle than this lever.