| 摘要 |
<p>PURPOSE:To inform battery exchange time to a user with allowance at a stage before than a final stage where the service life of a battery expires and to heighten an appealing effect for the battery exchange time. CONSTITUTION:A clock circuit 7 which starts clock by a clock start switch 10 depressed at a time when the battery 6 is exchanged is provided. A time before the final stage of the service life of the battery in the discharge characteristic curve of the battery is set as a prescribed time to be compared with the count time of the clock circuit 7. When the count time arrives at the prescribed time, the exchange time of the battery is informed. In other words, the density of display on a liquid crystal display device 13 is shifted so as to be clearly recognized, or an electronic buzzer 16 is rung, or message display to inform the exchange time of the battery is performed.</p> |
