GB1382704A - Alarm timepiece - Google Patents

Abstract

1382704 Electric alarm timepieces CITIZEN WATCH CO Ltd 23 May 1972 [5 June 1971] 24157/72 Heading G3T [Also in Division H3] An electronic battery-powered watch has an alarm buzzer 50, Fig. 4, which is actuated by closure of a switch 51 which causes a transistor 53 to conduct and consequently a transistor 52 of an alarm oscillator circuit 65. After a period determined by the time constant of a timing circuit 66 comprising resistor 56 and capacitor 57, a transistor 54 conducts which turns off transistors 53 and 52 and automatically terminates the alarm signal. Power is thus saved, even though transistor 54 conducts until switch 51 is opened. In the circuitry of Fig. 5 (not shown), the switch 51 is positioned between circuits 65, 66. In Fig. 6 (not shown), the oscillator circuit is an astable multivibrator. At an alarm time, axial movement of a cannon wheel 11, Fig. 1, causes projections 11a thereon to enter slots 12a in an alarm-setting wheel 12, thus connecting contacts 13c and 10a which constitute the switch 51. The buzzer 50 is formed by a membrane 24 to which is fixed a Piezo-electric or electro-strictive element 25. The back 27 has projections to raise the watch from the wearer's skin, and has holes 27c to release sound of the alarm. The time base 8 of the watch may be a balance wheel or a tuning fork.