发明名称 |
Radio-controlled wristwatch |
摘要 |
Provided is a radio-controlled wristwatch that receives a radio wave including day-related information from a satellite within a global positioning system, in which a cycle number of the day-related information is correctly updated even in a case where a power supply voltage drops. A radio-wave wristwatch (1) according to the present invention includes: reception means (11) for receiving a radio wave from a satellite and extracting day-related information therefrom; timekeeping-circuit halting means for halting an operation of a timekeeping circuit based on a power supply voltage; timekeeping-circuit halt detection means for detecting that the operation of the timekeeping circuit (13) has been halted by the timekeeping-circuit halting means; a nonvolatile memory (23) for storing the day-related information and a cycle number of the day-related information; and cycle-number updating means for updating, when the timekeeping-circuit halt detection means detects that the operation of the timekeeping circuit has been halted, the cycle number of the day-related information based on a comparison result between the day-related information extracted by the reception means (11) and the day-related information stored in the nonvolatile memory (23). |
申请公布号 |
US8824244(B2) |
申请公布日期 |
2014.09.02 |
申请号 |
US201214008403 |
申请日期 |
2012.03.13 |
申请人 |
Citizen Holdings Co., Ltd.;Citizen Watch Co., Ltd |
发明人 |
Kato Akira;Hagita Takushi |
分类号 |
G04C11/02;G04R20/10;G04R20/04 |
主分类号 |
G04C11/02 |
代理机构 |
Sughrue Mion, PLLC |
代理人 |
Sughrue Mion, PLLC |
主权项 |
1. A radio-controlled wristwatch, comprising:
reception means for receiving a radio wave from a satellite and extracting day-related information therefrom; timekeeping-circuit halting means for halting an operation of a timekeeping circuit based on a power supply voltage; timekeeping-circuit halt detection means for detecting that the operation of the timekeeping circuit has been halted by the timekeeping-circuit halting means; a nonvolatile memory for storing the day-related information and a cycle number of the day-related information; and cycle-number updating means for comparing, when the timekeeping-circuit halt detection means detects that the operation of the timekeeping circuit has been halted, the day-related information extracted by the reception means and the day-related information stored in the nonvolatile memory to each other, and updating the cycle number of the day-related information when the day-related information stored in the nonvolatile memory is larger than the day-related information extracted by the reception means. |
地址 |
Tokyo JP |