| 摘要 |
PURPOSE: To obtain an electric motor which generates less noise and vibration and in which a change in the magnetic flux of a magnetic coupling is outputted as the signal of the number of revolutions by means of a magnetic sensor built in the electric motor in order to control the speed by a method wherein the magnetic coupling is installed at a shaft part inside the electric motor and motive power is transmitted. CONSTITUTION: An electric motor is provided with a magnet 3a, for coupling, which is force-fitted to the shaft of a rotor on the side of the electric motor and with a magnet 3b, for coupling, which is force-fitted to the shaft of a rotor on the side of a load. Both magnets are turned synchronously by magnetic attractive forces magnetized in the plurality of poles. In addition, the electric motor is constituted in such a way that the change in the magnetic flux of the magnet, for coupling, which is force-fitted to the shaft of the rotor on the side of the electric motor is outputted as the signal of the number of revolutions by a magnetic sensor 8 built in the electric motor in order to control the speed. |
