| 摘要 |
PURPOSE:To improve operability by connecting a secondary cell through the normally closed contact of an AC relay and an operating switch to the tap of the exciting coil of a motor fan and connecting the secondary cell through the operating switch with a self-travelling control circuit. CONSTITUTION:When AC power is provided, a relay coil 12 is excited to open a contact 18. If a switch 26 is operated at this time, an LED 27 emits light. Consequently, photoreceptors 29, 30 output signals and a phase control circuit 15 functions to apply AC input onto a motor fan 13 while the contact in a relay 19 closes to apply DC voltage from a secondary cell 20 onto a self- travelling control circuit 21. The contact 18 closes upon interruption of AC power. When the switch 26 is operated, the contact of the relay 19 closes to feed the output voltage from the secondary cell 20 to the motor fan 13 and the self-travelling control circuit 21. |
