GB350615A - Improvements in snap action electric switches - Google Patents

Abstract

350,615. Tumbler switches. ARNOLD, C. L. and M. K. ELECTRIC, Ltd., Wakefield Street, Edmonton, London. March 26, 1930, No. 9709. [Class 38 (v).] Aquick-action switch has a spring or separate springs attached at the ends to the actuating member and the contactcarrying member and so disposed that the pivots of the contactcarrying member and actuating member lie within the figure formed by the spring or by the lines joining adjacent ends of the springs. The dolly 15 and contact arm 11 are pivoted at 10 to the bridge 2. Pins 17, 18 pass through and project from the dolly and contact arm respectively. A coiled spring 21 passes round pulleys on the pins 17, 18 and its ends are joined so that the spring embraces the three pins 10, 17, 18. A plate 25 is pivoted to a lug 24 on the bridge-piece and has a central aperture into which project the pins 17, 18. On moving the dolly to the right, the pin 17 engages the plate 25 turning it about the point 24. The plate then engages the pin 18 to move the contact arm past the dead centre position to give a quick break. Extensions 22, 23 on the contact arm engage end walls 3, 4 on the bridgepiece to limit the movement of the contact arm. Instead of a common pivot pin, the contact arm and operating lever may have separate pivot pins, and two springs may be used. Specification 266,863, [Class 38 (v), Electric switches &c.], is referred to.