| 摘要 |
<p>PURPOSE:To prevent a winding from burning due to overheat by energizing a heater by the conduction of an auxiliary thermistor, heating accelerationally a main thermistor by the heat and operating it. CONSTITUTION:When a rotor is restricted, an auxiliary thermistor 11 which operates at a low temperature is operated, its contact 21 is closed, an energizing circuit of a heater 12 is formed, and heated. A main thermistor 9 is heated by the heat from the heater 12 and the heat generated at a winding at the restricting time. Since the thermistor 11 is accelerationally heated and operated by both the heater 12 and the winding while the thermistor 11 is operated by the environmental temperature. In this manner, the restricting time of a rotor is shortened, and a damage such as the melting of the rotor conductor can be eliminated.</p> |
