Electric release device for electrical switching appliance e.g. for circuit breakers, has thermal release formed by polygonal multilayer metal, especially bi- or tri-metal

摘要

An electric release device for electrical switching appliance has a contact point with a thermal release which, with occurrence of an excess current, releases a latching point in a breaker mechanism for continuous opening of the contact point, and has an electromagnetic release which with a short-circuit current, directly opens the contact point. The thermal release (41) is formed by a polygonal multilayer metal, especially a bimetal or tri-metal and a heat transfer surface (48) is applied to the coil tube (33) and with which the thermal release (41) at least partly stands in close mechanical contact.