HEAT-SENSING SWITCH Russian patent published in 1998 - IPC

FIELD: miscellaneous devices for fire alarm, thermostatic control, process monitoring, etc. SUBSTANCE: switch has hermetically sealed case with one movable and one or two fixed contacts mounted at its end, as well as heat-sensing member made of foil strip whose material possesses shape memory effect. Movable contact has curved section; heat-sensing member material is preassigned to memorize rectilinear shape; its ends are rigidly joined with fixed contact above its curved section. Heat-sensing member is pre-deformed to relative elongation value not exceeding maximal martensitic shift ζ_m of material possessing shape memory effect. EFFECT: reduced size of heat-sensing member, improved stiffness of contacts, improved reliability and economic efficiency of device. 5 cl, 7 dwg