GB872652A - Electric switches - Google Patents

Abstract

872,652. Snap-action switches; retractive switches; mechanical switches, without quickaction. CUTLER - HAMMER Inc. March 21, 1958 [March 21, 1957], No. 9133/58. Class 38 (5). A switch has a movable contact biased against a shoulder on a driver element pivoted at one end on the base, the contact having an opening freely accommodating the driver element which is pivoted to engage the movable contact with a fixed contact, the movable contact sliding on the fixed contact after initial engagement is made when closing, and before disengagement when opening. The movable contact 34 co-operates with either of two fixed contacts 18 and is mounted on the driver element 38 which is pivoted at 44 in a terminal 16, the contact being biased against shoulder 36 by a spring 48. The upper end 42 of element 38 engages a recess in a slider 88 which is moved by an actuating dolly 80, either directly, Fig. 19, or through a lost-motion snap-action mechanism, Figs. 1, 6. This mechanism comprises a slider 86 having lugs 134 projecting into slots in the slider 88, each slider having a central aperture accommodating the end 84 of the dolly. When the dolly is tilted either way, it first engages one of the lugs 134 and moves the slider 86 along. This causes one of two springs 90 to be compressed, the other ends of the springs being held by the slider 88 which is itself held by spring-loaded plungers 92 engaging notches 124 in its lower surface. Further movement of the dolly brings its end 84 into engagement with the end 128 of the aperture in slider 88 which is thus forced along, the plungers 92 being forced down so that the stressed spring 90 moves the slider with a snap-action. Return springs 140 provide for retractive operation in each or either direction, or the springs 140 may be omitted. As shown, the switch has a central " off " position, but slider 88 may have only four notches 124 instead of six, so as to provide a change-over switch, Fig. 10 (not shown), and one of the contacts 18 may be omitted. Two contacts 34 may be actuated simultaneously, (Fig. 5, not shown). The dolly is surrounded by a resilient sealing member 72 and the joint between the base 10 and a cover 54 is sealed by a resilient seal 60.