| 摘要 |
<p>A tape drive mechanism comprises a crank-driven rod 34 whose little end pin 32 engages in a slot 44 of a guide 40 and in a slot 30 of a toothed quadrant 24 driving the tape wheel 16, the orientation of the slot 44 causing the little end pin to radially move in the slot 30 to impose on the quadrant 24 a harmonic motion, in addition to the harmonic motion of the crank, causing cyclical variation in the speed of the tape wheel. The position of the guide 40 may be adjustable and a pointer may be provided to indicate stroke. <IMAGE></p> |
