Electronic timepiece equipped with alarm
AssigneeCitizen Watch Co., Ltd.
InventorHeihachiro Ebihara
Life of this patent
Estimating the term…
Abstract
In an analog type of timepiece equipped with an alarm, an alarm time coincidence detection mechanism and a zero seconds detection mechanism are provided whereby switch contacts are closed when alarm time coincidence and zero seconds are detected respectively. A logical product is formed by combining signals from said switch contacts such that an operating signal to actuate an alarm device is produced with a high degree of accuracy. A memory circuit is incorporated to eliminate the effects of imperfect switch contact.
Claims8
An electronic timepiece having a source of a standard frequency signal, frequency divider means for dividing a frequency of said standard frequency signal to produce a standard frequency time signal, analog type current time indication means driven by said standard time signal for indicating current time, analog type alarm time indication means for indicating an alarm time, and external operating means coupled to said alarm time indication means for setting said alarm time, comprising:
- alarm time coincidence detection means coupled to said current time display means and to said alarm time indication means for detecting coincidence between the hours and minutes of said current time and the hours and minutes of said alarm time and for generating an alarm time coincidence signal when such coincidence is detected;
- zero seconds detection means coupled to said current time display means for detecting when the seconds of current time become zero and for producing a zero seconds detection signal when said seconds of current time become zero;
- alarm control circuit means responsive to said alarm time coincidence signal and said zero seconds detection signal for producing an alarm drive signal;
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- alarm generation means responsive to said alarm drive signal for generating an alarm drive signal;
- said alarm time coincidence detection means including a first set of switch contacts for detection of alarm time hours coincidence and a second set of switch contacts for detection of alarm time minutes coincidence, said first set of switch contacts being closed when alarm time hours coincidence occurs and said second set of switch contacts being closed when alarm time minutes coincidence occurs, and wherein said zero seconds detection means includes a third set of switch contacts, said third set of switch contacts being closed when zero seconds of said current time occurs.
An electronic timepiece having a source of a standard frequency signal, frequency divider means for dividing a frequency of said standard frequency signal to produce a standard frequency time signal, analog type current time indication means driven by said standard time signal for indicating current time, analog type alarm time indication means for indicating an alarm time, and external operating means coupled to said alarm time indication means for setting said alarm time, comprising:
- alarm time coincidence detection means coupled to said current time display means and to said alarm time indication means for detecting coincidence between the hours and minutes of said current time and the hours and minutes of said alarm time, and for generating an alarm time coincidence signal when such coincidence is detected;
- zero seconds detection means coupled to said current time display means for detecting when the seconds of current time become zero and for producing a zero seconds detection signal when said seconds of current time become zero;
- alarm control circuit means responsive to said alarm time coincidence signal and said zero seconds detection signal for producing an alarm drive signal;
- said alarm time coincidence detection means including first switch means for detection of alarm time hours coincidence and second switch means for detection of alarm time minutes coincidence, said first switch means being closed when alarm time hours coincidence occurs and said second switch means being closed when alarm time minutes coincidence occurs, and wherein said zero seconds detection means includes third switch means, said third switch means being closed when zero seconds of current time occurs.
Dependencies are inferred from the claim text.