| 摘要 |
<p>PROBLEM TO BE SOLVED: To make a printing device in a small construction by stopping transmission of the driving force to a shaft using a changeover means when a medium sensor senses passage of a medium, and putting a transport roller in idling condition relative to the shaft. SOLUTION: When the second medium sensor senses passage of a sheet of paper, a control part stops current feed to a coil 30, and then an actuator 27 is rotated by the energizing force of a spring 29. Accordingly a feed roller shaft 7 moves in the direction of Arrow D, and the second coupling part 26 separates from the first coupling part 25. Then the external drive motive for the feed roller shaft 7 ceases. Pins 22a, 22b are set off from notches 23a, 23b, and transport rollers 6a, 6b are put in idling condition relative to the feed roller shaft 7. The transport rollers 6a, 6b continue idling with the frictional force of sheet until its trailing edge has passed pressure rollers 20a, 20b.</p> |
