| 摘要 |
PURPOSE:To enable the mechanical displaying of a battery life with a less number of additional parts, by driving a display plate which warns the termination of the battery life with a step motor for the wheel trains of a timepiece as a driving source. CONSTITUTION:The second hand 4, the minute hand 5 and the hour hand 6 are provided in the space between the dial 2 at the center of a watch frame 1 and a front cover 3, and a display window 7 is disposed in the position of the time digit ''3'' of the dial 2. The digit ''3'' of the plate 8 is normally visible through the window 7, and when the battery voltage drops, the characters ''exchange battery'' are visible. The dial 8 is driven by a step motor for the wheel trains of the timepiece that drive the hands 4-6 as a driving source. When the battery voltage drops down to a specified value or below in this case, the output pulse of a control circuit 37 is impressed through a driving circuit 38 to a motor coil 39 by the output of a detection circuit 40, and a rotor 33 is rotated stepwise in normal and reverse directions. The battery life is predicted by the irregular operation of the second hand 4. |
