By means of a illegal probe, in particular thermal probe, gradually controlled electric switch with a magnetic snap action

摘要

806,768. Electromagnetic switches; contactmembers for switches. RHEOSTATIC CO. Ltd. Feb. 6, 1957, No. 4099/57. Class 38 (5). In a magnetic snap-action switch in which the magnet 11 is movable between two armatures 7, 8, the magnet is riveted by a contact 13 to an insulating member 12 carried on a bi-metal strip 1 mounted on a resilient spring 4. The latter is mounted on a fixed bracket 2 and urges a member 17 against a temperature-setting screw 16 carrying a calibrated dial 14. The armature 7 is fixed on a bracket 9 and has a fixed contact or stop screw 5 adjustably mounted on it so as to allow independent adjustment of the gap between the magnet 11 and the armature 7. A fixed bracket 10 carries a second adjustable fixed contact or stop-screw 6 on which the cup-shaped armature 8 is threaded so that it also may be adjusted relative to the screw 6. A spring washer 18 is provided to maintain contact pressure between members 6, 8 and 10. The bi-metal strip 1 may be replaced by a resilient spring strip for operation by a rod-and-tube thermal member or by a pressure-operated bellows or diaphragm.