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Description
Round eccentric 1 is keyed to driving shaft 9 which rotates about fixed axis A. Gear 2 with 96 teeth is freely mounted on eccentric 1 but is prevent ed from rotating by lever d. Gear 3 with 120 teeth is freely mounted on shaft 9. Gears 2 and 3 mesh with planet pinion 4. Pinion 4 is carried by double-arm link 5 which is also keyed to driving shaft 9. When driving shaft 9 rotates, gear 3 is rotated by pinion 4. The transmission ratio is i₁₃=120/96=5/4. At the other end of link 5 is roller 6 which runs on a flange of gear 3. This flange is circular and has a small depression a in the periphery. The size of depression a is such that when roller 6 drops, pawl 7, rigidly mounted together with roller 6 on a pin, engages ratchet wheel 8, keyed to driven shaft 10. Each time the pawl engages the ratchet wheel, the latter is turned forward 1/12 revolution after which roll 6 runs on top of the flange again. Thus, when driving shaft 9 makes 1¼ revolutions, driven shaft 10 makes 1/12 revolution in the same direction. $2734$RG,ML$
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