| 摘要 |
<p>PURPOSE:To eliminate the complexity accompanied with automatic power supply breaking during the use of commercial power source and to lengthen life of the battery by making a detecting circuit use an output signal from the timer to actuate an automatic power supply breaking circuit only when power is supplied from the battery. CONSTITUTION:A no-operation detecting means 10 detects that units to be supplied with power are all in a no-operation state for a predetermined time duration, and a control means 12 that monitors that commercial power supply is in a state of supplying when a no-operation detecting signal is output invalidates a no-operation detecting signal. Accordingly, even when a no- operation state continues for a predetermined time duration, the automatic power supply breaking means 12 is actuated to protect power supply from being interrupted. With this, one can be released from the complexity of reapplying power supply, thereby preserving the function of lengthening life of the battery.</p> |
