GB729250A - Improvement in electric flasher device - Google Patents

Abstract

729,250. Thermal switches; switches, partly electromagnetic. HOLLINS, J. R. Jan. 9, 1953 [Jan. 9, 1952], No. 724/53. Class 38 (5). A switch operating substantially the same as that disclosed in Specification 729,249 has its armature 32 pivoted on an arm 28 of the frame 17, the armature carrying a spring 37 supporting the contact 34. On expansion of the resistance wire 30, contact 25 engages contact 22 whereupon signal lamps 13, 13<SP>1</SP> are lit and the armature is attracted to engage contact 27 with contact 25 and close contacts 34, 36 to energize the pilot lamp 12. On cooling of the wire 30 the armature 32 follows the movement of the spring arm 23 by pivoting counter-clockwise, the relative movement between the contacts 25, 27 causing cleaning of their surfaces. Eventually the contacts 25, 27 separate and the cycle repeats. In a modification, Fig. 2, an arm 52 mounted on an insulating block 51 and connected to a further pair of signal lamps 57, 57<SP>1</SP>, carries a contact 53 co-operating with a back contact on the spring 37. When switch 15<SP>1</SP> is closed lamps 57, 57<SP>1</SP> are illuminated and are extinguished when the lamps 13, 13<SP>1</SP> are illuminated and the armature is operated, thus the two pairs of lamps flash alternately.