| 摘要 |
PURPOSE:To reduce the labor of maintenance and inspection by flowing a current to a winding of a stator yoke provided oppositely to a rotary yoke which rotates together with a rotor of a brushless motor, thereby electrically braking without contact. CONSTITUTION:A permanent magnet type rotor 3 and a rotary yoke 4 are provided at a rotational shaft 2, and a stator 5 and a stator yoke 6 opposite to them are provided. A current of the polarity matched by detecting the position of a permanent magnet of the rotor 3 by a control substrate 8 is flowed to a coil 7 to produce rotary force. The yoke 4 is provided with a plurality of projections (4 in the drawing) 41 radially outwardly, and the yoke 6 is provided with the same number of inward projections 61 and provided with a brake winding 11. When an electric railcar approaches, a motor section is rotated to lower a barrier, the energization of the motor is stopped at the prescribed position, a coil 11 is energized to electrically brake it. In this manner, a brush can be eliminated, the barrier is stopped accurately by the contactless electric brake, thereby reducing the labor of maintenance and inspection. |
