| 摘要 |
PURPOSE:To make it possible to weaken collision at the time of finish even if a push-up rod is driven at a high speed, by detecting a position slightly before a type push-up rod completes the pushing-up to a type bar to reverse the driving current of a hollow coil. CONSTITUTION:When a current is supplied to a hollow coil 20, said coil is attracted by the magnetic force of a permanent magnet 17 to project a push-up rod 15 and the type 11 in a type case 10 pushes up a type bar 13. When a shutter metal fitting 24 passes an intermediate sensor 27, the positive and negative of a current is changed over by a positive and negative change-over switch and, at the same time, a timer is set. Whereupon, the hollow coil 20 receives driving force generated in a reverse direction and is gradually lowered in the speed thereof while a positive current is again flowed to the coil 20 in the timing of the timer and, when an upper sensor 25 is operated, a current is turned OFF. By this method, collision is weakened even if the hollow coil is driven at a high speed and a printing speed can be enhanced while abrasion and noise are suppreseed. |
