GB862294A - Improvements in or relating to delayed action electric switches - Google Patents

Abstract

862,294. Electromagnetic switches; retarding action of switches. TELEMECANIQUE ELECTRIQUE. Feb. 10, 1958 [March 7, 1957], No. 4295/58. Class 38 (5). A time-delay switching device operable by the spindle 31 of an electromagnetic contactor is in the form of a detachable unit that can be fitted to a contactor in two positions 180 degrees apart according to which direction of movement of the contactor spindle is required to operate the device. A rapid-break switch 1 has a button 3 spring loaded to bear against a protuberance 2 on a T-lever pivoted at 36 and coupled by pin 7 to a pneumatic retarder 8. When a finger 33, secured to the contactor spindle 31, moves as indicated by the arrow f 1 it impinges on the arm 5 so that the button 3 of the switch and the bellows of the retarder are depressed (a valve 9 allowing this to occur freely). When the finger 33 moves back the spring loading of switch 1 forces the protuberance 2 in the direction of arrow f 2 but the retarder 8 delays the restoration of the switch since air returns slowly to the bellows through a narrow calibrated orifice. The switch 1 and retarder assembly may be reversed in its casing 11 by removing screws 12 and 13 and reassembling (using hole 14 for screw 13) so that the above described operation occurs for the opposite movements of the finger 33, which then engages arm 4 of the T-lever (Fig. 6, not shown). The device is secured to a fixed part 20 of the contactor by means of a plate 21 on which the casing 11 is easily fitted or dismantled by virtue of a slotted bracket 24 and a tongue 22 slotted to be clamped by a screw 27. In a modification (Figs. 7, 8 and 9, not shown) the protuberance 2 is on arm 4 of the T-lever and the delay is thus applied to the opposite movement of the switch button 3.