GB1206318A - Improvements in or relating to electric switches - Google Patents

Abstract

1,206,318. Mechanical switches. GEMCO ELECTRIC CO. 13 March, 1968 [23 March, 1967], No. 12194/68. Heading H1N. A switch has fixed and movable contacts 16, 16a and 18, 18a, Fig. 1, which engage when projections 26 on the movable contacts are received in recesses 28 in a control member 12 which may be rotatable, as shown, or axially movable. Each movable contact comprises two resilient conductive prongs 21, swingable with respect to a plastics cylindrical member 22, and a resilient prong 30 integral with prongs 21. When the projection 26 is received in the recess 28, prong 30, which bears against the housing and exerts a tension on prongs 21, swings prongs 21 and urges the contacts 18 thereon into engagement with the fixed contacts 16 (dotted line position). Prong 30 thereafter flexes prongs 21 so that contacts 18 wipe over contacts 16 (solid line position) thereby cleaning the contacts. Contacts 16, 16a may be in one or two circuits. In another embodiment, Fig. 7, each movable contact comprises a rigid conductive arm 42 swingable about a part-cylindrical mounting (46, Fig. 4), a spring 54, and a contact element 56 having contacts 52 and a lug 60 to tiltably support the element on arm 42. Tension spring 54 initially causes contacts 52 to swing into engagement with contacts 40 (dotted line position) and thereafter compresses a spring 62 on the movable contact so that element 56 is tilted and contacts 52 wipe over fixed contacts 40 (solid line position).