| 摘要 |
<p>A conventional three pole D.C. motor has a third brush (9) placed at an acute angle of 60 degrees to one of the normal brushes (6, 7) and positioned to contact the commutator plates (C1, C2, C3). A motor energizing circuit is normally off and is capable of energizing the normal brush (6) and, alternately, the third brush (9) which is displaced 60 degrees from the normal brush (6). A single intermittent rotation begins with the normal brush (6) being energized, and continues in a conventional manner until a rotation sensor at approximately 300 degrees cuts off the normal brush (6) and energizes the third brush (9) for a specific period, during which time all armature poles are of opposite polarity to the adjacent field poles (1A, 1B), which causes the motor to be magnetically braked at the 360 degree full rotation point. At the end of the braking period, all power is removed until the next intermittent cycle.</p> |
