| 摘要 |
PURPOSE:To reduce generation of noise and abrasion of a mechanism part, by controlling excitation of a solenoid in accordance with a position sensor for detecting the passage of a support shaft for a type crown through a midpoint between the first position and the second position and with the period of time from the moment the solenoid is driven or opened to the moment the position sensor generates an output. CONSTITUTION:With a type-selecting command A inputted from a microcomputer, a controlling circuit 13 outputs an exciting signal B. An exciting current D is supplied from a driving circuit 14 to the solenoid 10, which attracts a transmitting gear 9. By the attraction of the gear 9, a toothed cam 8 is rotated to move the support shaft 5 from the first position to the second position, and a position signal E is outputted from a photo-interrupter 18 when the shaft 5 reaches the midpoint between the first and second positions. The controlling circuit 13 regulates the time width of the exciting signal B in accordance with the period of time TO from the leading edge of the signal B to the leading edge of the position signal E, whereby the type crown 1 is led to an upper stage position at an appropriate velocity. Returning the type crown 1 to a lower stage position is similarly conducted. |
