Ratchet Mechanism

Input: grey crank oscillating.
Output: violet slider that linearly moves interruptedly.
Tooth number of green wheel Zg = 12.
Tooth number of yellow wheel Zy = 11.
Blue pawl contacts the green wheel.
Orange pawl contacts the yellow wheel.
The green wheel has helical joint with pink screw.
The yellow wheel has prizmatic joint with pink screw.
The gravity maintains contact between the wheels and the pawls.
The screw pitch is P mm.
12 double strokes of the input crank make the green wheel turn 1 revolution and the yellow wheel turn 1 + 1/11 revolutions. Thus the screw turns 1/11 rev. in relation with the green wheel (nut) and the slider moves P/11 mm (small displacement).
The video also shows case when the orange pawl does not engage with the yellow wheel. The latter is immobile so the screw can not rotate. 12 double strokes of the input crank make the green wheel turn 1 revolution and the slider moves P mm (large displacement) in the opposite direction (in the same direction if Zg = 11, Zy = 12).

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