| 摘要 |
PURPOSE:To prevent the overheat of a motor by connecting a heat-conductive member, which is made so as to cover a thermal relay, consisting of a heat-- conductive and well conductive material, to a coil in series. CONSTITUTION:A current at the same value with the current flowing in a coil flows in the heat-conductive member 23 connected in series to the coil constituting a rotor. For this reason, in case that an undesired large current flows to the coil, Joule's heat proportionate to the Joule's heat generated in the coil is also generated in the heat-conductive member 23, too, and this heat can be transmitted directly to the thermal relay 4. Accordingly, in case that the thermal relay 4 goes up to above the specified temperature, the power supply to the coil is stopped by opening the contact. Hereby, the overheat of the motor caused by an abnormal current can be prevented surely. |
