Improvements in thermal switching devices for automatically regulating the supply of current to electrical apparatus

Abstract

Abstract 536,701. Thermal switches. BRITISH THOMSON-HOUSTON CO., Ltd., CLOUGH, F. H., and MILWARD, V. E. Feb..23, 1940, No. 3414. [Class 38 (v)] Heating apparatus is energized for a controllable period in each cycle of operation of a thermal responsive element operated by its own heating coil switched on and off at pre-determined positions of the thermal device. A bi-metallic strip 1 is caused to open by heat in a coil 3, wound about it, and energized through contacts 7. On reaching the upper stop 9 the contacts 7 are separated and the thermal strip cools until by pressing the stop 8 the contacts 7 are again closed and the cycle repeats. A magnetic " detent " 10, 11 may be used to ensure a snap action. An adjustable contact 13 co-operates with a contact 14 borne by the thermal strip to regulate the extent of the period during which current passes to the heating apparatus controlled.

Inventors

No inventors recorded.

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