GB629300A - Improvements in electrical snap acting switches - Google Patents

Abstract

629,300. Snap-action switches. COOK, F. L. Dec. 7, 1946, No. 36228. Convention date, Dec. 8, 1945. [Class 38(v)] A tumbler switch comprises an insulating base 10 containing bent resilient contact carrying arms 13, 14 secured at one end by terminals 15, 16, and stressed to bear at their free ends against a projection 10<SP>2</SP> on the base. The latter projection, together with a projection 10<SP>1</SP> form bearings for pintles 12<SP>1</SP> of the tumbler 12. A movable contact carrying plate 18 pivoted in a groove 17 in the base and connected by a flexible strip 20 to a terminal 19, Fig. 9, has a slot 18' engaging a telescopic link 29 of a spring toggle pivoted to the underside of the tumbler by a pointed member 29<SP>2</SP>. Movement of the tumbler to either side of the dead-centre causes the plate 18 to make contact with arm 13 or 14 urging it away from the projection 10<SP>2</SP> against an abutment 10<SP>3</SP>, Fig. 4. The contacts on the plate and arms may be of silver, and rubber inserts 22 are provided for arresting the tumbler. Fig. 13 shows a single pole switch in which the movable contact plate 18 has a stop 26 engaging an abutment 10<SP>3</SP>, and a contact arm 13 is held rigid between the projections 10<SP>1</SP>, 10<SP>2</SP> and another abutment 10<SP>3</SP>. In Fig. 17 (not shown), the contact plate is resilient and rigidly secured to the base, alternatively a rigid contact plate may be secured by a flexible element. Fig. 11 shows a flush-mounted switch in which the movable contact plate 18 is pivoted at its upper end 18<SP>2</SP>. In Fig. 12 the movable contact 18 is tubular and pivoted at 24.