Title: Analog electronic clock
Application Number: 200480035520 Application Date: 2004.11.29
Publication Number: 1886703 Publication Date: 2006.12.27
Approval Pub. Date: Granted Pub. Date:
International Classifi-cation: G04C3/14
Applicant(s) Name: Citizen Watch Co., Ltd. Address:
Inventor(s) Name: Kitazawa Isao, Murakami Akiyoshi
Attorney & Agent: li xianglan
Abstract:
     Impact detecting resistors (141), (143) of an impact detecting circuit (104) detect a counter electromotive force of a step motor (105) generated due to an impact. This counter electromotive force is amplified applying a predetermined period and a predetermined chopper-width by a chopper-amplifying waveform shaping circuit (118). Therefore, even a light impact can be detected. Inverters (145), (146) compare these impact detecting signals (S22), (S23) with a threshold value and detect an impact when the signals exceeds the threshold value. A controlling circuit (102) provides a lock pulse to the step motor (105) through signal lines (AA), (BB) when an impact is detected, brakes rotation of a rotor (162) thereby preventing a deviation of the time displayed with a second hand (106).
Time: 9