| 摘要 |
PURPOSE:To make it possible to reduce noise, in a typewriter of which the tractor feed means is made detachable, by releasing a ratchet means by pressing a ratchet lever projection by the leading end of an attachment part in attaching operation. CONSTITUTION:In the friction feed mode of paper 17, a roller 11 is pressed to a platen 4 through a leaf spring 16 and a paper guide plate 12 and the paper is fed by the friction between the roller 11 and the platen 4 while a contact element 9 is engaged with and pressed to a ratchet gear 6 to prevent the shift of the platen 4 in the rotary direction thereof. On the other hand, in a tractor feed mode, the attachment plate of a tractor unit 2 is meshed with the platen shaft 5 and a ratchet lever 7 is pushed down by the leading end thereof to detach the contact element 9 from the ratchet gear 6 and, when a bail lever 24 is revolved to right, the crescent part 15a of a shaft 15 erects and the leaf spring 16 is pushed down and the guide plate 12 and the roller 11 are separated from the platen 4 to release the friction mode. By this mechanism, attachment and detachment can be easily performed and noise can be suppressed to a lower degree. |
