GB1389782A - Timer - Google Patents

Abstract

1389782 Cam mechanisms; linkwork TAMURA ELECTRIC WORKS Ltd 6 April 1973 [7 April 1972] 16480/73 Heading F2K [Also in Division H1] The time-setting mechanism for operating a switch 15 of a set-time display device (Fig. 5, not shown) comprises a generally "T"-shaped lever 5 pivoted at 6 and having pins 7a, 7b, 7c at its extremities, a spring 12 urged cam latch 10 acting via the pin 7c, against a compression spring 8, to maintain the pins 7a, 7b in peripheral contact with notched discs 3, 4 mounted on relatively fast and slow intermittently rotated shafts 1, 2 driven by a synchronous motor (not shown), the shafts 1, 2 being rotated in accordance with time, and each completing one revolution in 1 hour and 12 (as shown) or 24 hours respectively. The notched discs 3, 4 may be pre-set on the shafts 1, 2 by a pair of timesetting discs 16 which are connected to adjustably rotate and set the discs 3, 4 on the shafts 1, 2 by a pair of planetary gear mechanisms each of which comprise a pair of sun gears 21, 20 secured to the discs 16 and 3 (or 4) respectively, a stepped planet wheel 18, 19 meshing the suns 21, 20 and being carried by a stub shaft 17 fast with disc 16. The arrangement is such that at any pre-set timing of the device when the notched plates 3, 4 jointly are aligned to receive the pins 7a, 7b, the cam latch 10 rocks the lever 5 to enter the pins 7a, 7b in the notched plates 3, 4, whereby the cam latch 10 is further spring urged at 12 to then operate the switch 15 at which point the compression spring 8 acts to disengage the lever 5 from the discs 3, 4 whereby the timing device drive continues uninterrupted.