EP 0376660 A2 19900704 - Improvements relating to thermal switches.
Title (en)
Improvements relating to thermal switches.
Title (de)
Thermische Schalter.
Title (fr)
Interrupteurs thermiques.
Publication
Application
Priority
GB 8830299 A 19881228
Abstract (en)
A snap-acting bimetal blade for use as a thermally-responsive switch actuator has a generally rectangular outer shape and has a generally rhomboidal cut-out defining two spaced-apart and tapering legs connected together at their opposite ends. Such a blade shape has advantageous characteristics as regards the forces and movement that can be developed in switching operations. A thermally-responsive switch incorporating such a bimetal blade has first and second spaced-apart metal parts, one of which is formed of rigid, electrically-resistive material and the other of which is a spring member, first and second contacts provided on such parts, a bimetal blade as aforesaid welded to one of the parts, and an insulating push rod arranged for transferring switch-operating movement of the bimetal to the spring member for operating the switch. When used as a motor protection switch, the bimetal operation is dependent upon heat generated by current flow in the electrically-resistive part of the switch and the switch can be made relatively insensitive to large currents flowing for short durations, but sensitive to longer term lower currents, and can have a high ratio of "off" time to "on" time.
IPC 1-7
IPC 8 full level
H01H 37/54 (2006.01); H01H 69/01 (2006.01)
CPC (source: EP)
H01H 37/5418 (2013.01); H01H 69/01 (2013.01); H01H 2037/525 (2013.01)
Designated contracting state (EPC)
AT BE CH DE ES FR GB GR IT LI LU NL SE
DOCDB simple family (publication)
EP 0376660 A2 19900704; EP 0376660 A3 19910925; GB 2227884 A 19900808; GB 8830299 D0 19890222
DOCDB simple family (application)
EP 89313539 A 19891222; GB 8830299 A 19881228