Model: N18 Crown Wheel Ratchet Lifting Mechanism
This device consists of a ratchet wheel with rectangular shaped teeth on the side or rim, a lever, two pawls and twin pulleys to lift a weight. The placement of the teeth on the face of the wheel is called a crown wheel ratchet by Reuleaux. There are forty eight teeth around the wheel in the model. One pawl moves with the lever and engages the wheel. The other pawl locks the wheel when the lever moves to the left.

Francis Moon 2001-00-00

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