| 摘要 |
PURPOSE:To reduce force required for sway of an oscillating gear by swaying the oscillating gear by means of its turning reaction force against a load gear and interlocking the oscillating gear selectively with a pair of driven gears. CONSTITUTION:When a position regulation plate 52 is displaced to an illustrated position, a support axis 44 of an oscillating gear 21 is guided in a central regulation groove 57a of a position regulation hole 57 to be regulated for position, while a support axis 43 of an oscillating gear 20 is guided from a central regulation groove 56a of a position regulation hole 56 into an opening 56c, sway of the oscillating gear 20 being possible. Here, when a motor 32 is driven, a driving gear 23 is driven in (a) direction, and further the oscillating gear 20 is swayed in (c) direction along with a swaying arm 41 while being driven for rotation in (b) direction, the oscillating gear 20 being interlocked with a medium gear 18. At this time, since an arm R2 for force F2 which produces force F1 required for swaying a sway arm 41 is longer than an arm R1 for force F2, force F2 will do even if small. |
