| 摘要 |
<p>PURPOSE:To reduce the impact produced when a head van is returned by dividing a circumferential gear part of a play gear into a head van advancing gear part and a head van returning part, and making partially the teeth of head van returning gear part toothless part to make the head van returning speed faster than that of the gear part. CONSTITUTION:A play gear 8 receives the power of head van springs 47, 48 of a head van 45 via a play spring 15 and a head van advancing pin part 13a. A play arm 13 is turned clockwise by the force which tries to turn counterclockwise centering on a play arm rotary shaft 14. Thus a head van returning gear part 8d, head van returning toothless part 8i and a head van returnining gear part 8e are set successively opposite to a flywheel gear 12. Then the arm 13 is turned at a speed synchronous with the revolution of the gear 12 while those gears engage with each other. Thus the revolving speed is reduced compared with the toothless part. Therefore the arm 13 having a contact with a cam part 8a is turned slowly to return the head van 45 at a corresponding speed.</p> |
