| 摘要 |
PURPOSE:To ensure that paper feed by friction feeding and that by a pin feeding mechanism conform to each other and prevent a paper from jamming, by providing a transmission mechanism comprising pin feed gears connected to a rotating body, and providing a speed change gear for obtaining a variable circumferential velocity of a platen, in a power transmitting path extended from a driving gear to the platen. CONSTITUTION:Gears 20, 21 are connected to a driving shaft 9 to constitute a pin feed transmission mechanism. A two-stage gear 24 is fixed to the right end of a platen shaft 23 to constitute a platen transmission mechanism 25. The gear 23 comprises two speed change gears 26, 27 selectively engaged to a small-diameter gear 18 of a driving gear 19, the number of teeth of the gear 26 being smaller than that of the gear 27 by one piece. When feeding a paper 37 by a pin feeding mechanism 11, the circumferential velocity of a platen 1 is set to be higher than that of a rotating body 13 in the mechanism 11, thereby preventing the paper 37 from sagging on the periphery of the platen 1. When feeding another paper by friction feeding, the circumferential velocity of the platen 1 is returned to a normal velocity. |
