| 摘要 |
PURPOSE:To provide an inexpensive and highly reliable timer device by combining a mechanical timer and an electronic timer, and commonly using one load contact to a heater. CONSTITUTION:When a knob 1 is turned to the right, a switching contact 4 remains open and a load contact 5 closes, thereby supplying electricity to a heater 6. At the same time, a power source is supplied to a driving circuit 8 of a pulse motor 7, and one pulse in 4 seconds is applied to a motor 7. After a constant time, cams 2, 3 return to initial positions, thereby interrupting the conduction of electricity to the heater 6. When the knob 1 is turned to the left, the load contact and the contact 4 close to conduct electricity to the heater 6. An electronic timer circuit 11 operates to output one pulse in one second to the circuit 8 after a constant time. Hence, the pulse motor 7 runs fast to open the contact 5, thereby interrupting the conduction of electricity to the heater 6. |
