| 摘要 |
PURPOSE:To contrive a low cost and compact size with reduction of the number of parts in such a way that the oscillating center shaft is rotatably set up by means of an inductor type synchronous motor with unbalanced magnetic polar arrangement which turns instantaneously in the reverse direction, when locked during rotating condition. CONSTITUTION:It is supposed that driving torque from an auxiliary motor 16 is transferred to a neck shaft 14, and the neck shaft 14 starts turning. When it turns clockwise until a lock-up pin 14d makes contact with a lock pin 18a to be locked instantaneously it starts turning counterclockwise, because the auxiliary motor 16 is an inductor type synchronous motor with unbalanced magnetic polar arrangement and it turns counterclockwise until a lock-up pin 14a makes contacts with another lock pin 18b. By such a constitution, the number of parts can be sharply reduced, consequently resulting in possibility of realizing a low cost and a more compact overall dimension. |
