Model: N03 Coupling With Ratchet and Pawl
This model consists of two co-axial discs each with its own crank. The dark disc has conventional saw teeth and the rear disc has a single pawl which can engage the ratchet and lock in one direction and slide over the teeth in the other direction. A spring lever is attached to the front shaft whose end slides between two pins on the pawl. Motion of the front crank will move the lever to rotate the pawl onto the ratchet thereby locking the two discs together. If the front crank moves counterclockwise relative to the pawl disc the spring lever acts to disengage the pawl from the ratchet teeth and the two discs can rotate independently. The lever is only spring loaded onto the front axial and can slip relative to the motion of the front crank.

Francis Moon 2004-07-00

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