GB729926A - Improvements in or relating to devices driven by springs adapted to be intermittently wound by electro-magneticmeans - Google Patents

Abstract

729,926. Reciprocating. electric motors. SMITH & SONS (ENGLAND), Ltd., S. June 15, 1953 [June 13, 1952], No. 14950/52. Class 35. [Also in Croup XVIII] A device maintained in operation by a spring which is intermittently wound by a solenoid and armature energized by a source of electricity, the winding action being initiated when the extension of the spring reaches a predetermined value, comprises a member acted upon and displaced by the armature upon energization of the solenoid and means to maintain the solenoid in an open-circuited condition should said displacement fail to exceed a predetermined amount. The invention is described as applied to clock in which the mainspring 17, Fig. 1, pulls the lever clockwise and the pawl 19 steps-on the ratchet 20 in the train. A contact 5 carried by the member 6 meets a contact 4 to close the circuit from a battery (not shown) to the solenoid 1. The armature 2 is thereby moved clockwise about its pivot 3 against the pressure of a spring 22 to return the lever 6 to its initial position. The end 10 of an L-shaped spring 9 carried by the lever 6 normally wipes past a fluid member 12. If, however, the E.M.F. of the battery falls below a minimum value and the impulse given to the armature 2 is insufficient fully to return the lever 6 the end 10 of the spring member 9 engages in the notch 15 of the member 12 so that the lever 6 is held in such a position that the contacts 4, 5 are open, Fig. 4 (not shown).