GB1302591A - - Google Patents

Abstract

1302591 Timed control of electric circuits AUTOMATIC TIMING & CONTROLS Inc 3 Feb 1970 [28 July 1969] 5180/70 Headings G4D D1D5 D4A2 D5A5 D5C3 and D5X1 [Also in Division H1] A timing or counting apparatus (20), Fig. 1 (not shown), has a digital display formed by indicia wheels 30 which are settable by corresponding push buttons 32. A synchronous or impulse motor (50), Fig. 4 (not shown), drives a shaft 53 and hence a gear 59, the drive being transmitted in the timing condition to the least significant digit wheel 30 by means of a gear 60 and an idler 64 which acts as a clutch. Alternatively the drive may be from an external source. The idler 64 is carried on a movable shaft 67 which also carries pinions 65 to transmit the drive to successive indicia wheels 30 in the manner of an odometer. The digit wheels 30 also carry respective cardioid cams 83 which are used for automatic resetting at the end of a timing cycle, the indicia being rotatably adjustable with respect to the cams by use of the push buttons 32 when the cams 83 are locked by projections 81b on arms 81. A portion 90a of an arm 90 prevents setting during a timing operation except by use of override push button (34), Figs. 1 and 16 (not shown), which disengages the clutch, gear 64 without affecting a switch (106), Fig. 7 (not shown), in a controlled electric circuit. At the end of a timing cycle, the digit wheels 30 all read zero and have their arcuate depressions 30j uppermost. This condition is detected by rollers 92 carried on a shaft 93, a switch lever 117 being then released from a hooked member 98 to operate a switch (112) controlling the motor (50) or an actuating solenoid (69), Fig. 5 (not shown). The latter also operates the external load switch (106).