GB1399443A - Clock devices - Google Patents

Abstract

1399443 Electronic timepieces CASIO COMPUTER CO Ltd 10 April 1973 [13 April 1972] 17035/73 Heading G3T Relates to a time setting or correcting arrangement in an electronic timepiece. In normal operation timing pulses from a generator 16 Fig. 2 are counted by a counter 18 which produces a carry pulse every second to a seconds counter 21. The latter sends a carry pulse every minute to minute counter 23 which sends a carry pulse every hour to hours counter 24. The outputs of counters 23, 24 are applied via respective decoders 25, 26 and drivers 27, 28 to operate a digital or analogue display. To correct the time indicated, a key 14 is depressed causing the resetting of the counter 18 and clearing the seconds counter 21. At the same time a signal from key 14 acts as a minutes stepping signal to step the minutes counter 23 by one step. AND gates 17, 20 are blocked, the counting operation of counter 18 is stopped and input to seconds counter 21 interrupted. The key 14 is released and counting recommenced when the time displayed agrees with a standard time. To correct for more than one minute the key is repeatedly depressed and released. Fig. 3 (not shown), illustrates a signal generating circuit which is used in conjunction with the key 14 to supply a stepping signal to the minutes counter a predetermined interval after the key 14 is depressed. Fig. 4 (not shown), illustrates a delay circuit for stepping the minutes counter a predetermined interval after the key 14 is released. The display may be digital and employ liquid crystal elements or alternatively may be analogue and comprise sixty "minute" display elements and twelve "hours" elements arranged around the periphery of a circle.