LEONARDO DA VINCI - Using the toothed wheel to transmit motion - Continuous rotary motion producing alternate rotations - Semi-toothed pinions and pin-gear wheel

Madrid Ms. I (BNM), fol. 17r (detail)

The driving pinions are toothed on half their surface only: "As crank a is constantly turned in the same direction in this instrument, the main wheel turns once in one direction and once in the other, as demonstrated by the teeth of the pinion."

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