GB1078025A - Adjustable electric time switch - Google Patents

Abstract

1,078,025. Time switches. ROTHERHAM & SONS Ltd. April 30, 1964 [May 3, 1963], No. 17490/63. Heading H2B. A time switch of the kind wherein a shaft 12 is driven by a synchronous motor via reduction gearing and two (or more) actuating arms 10, 11 operate contacts (not shown) at preset times comprises an extension 12a on which are coaxially mounted tubes 28 and 29 having the arms 10 and 11 secured at one end respectively and corresponding adjusting knobs 13, 14 at their other ends. Friction washers 26 and 27 allow knobs 13 and 14 to be set relative to a dial 15. Resilient three - armed spiders 22 and 25, respectively drive arms 10 and 11 via friction washers 21 and 32, these spiders being themselves driven by means of holes in the ends of their arms engaging with pins 30 on the ends of corresponding arms of a six-armed resilient spider 19 engaged by a flat on shaft extension 12a. Cams 31 are provided on actuating arms 10 and 11 such that they can pass between the co-operating spider arms by lifting the pin 30 out of its associated hole (as shown in the case of arm 10). Since the two other arms of the respective spider 22 or 25 are left in engagement with spider 19 no interference with the angular position of the spiders results, and adjustment of one actuating arm does not affect the position of the other.