Model: N02 Centrifugal Unlocking Ratchet Coupling
This model consists of two coaxial discs each with a separate crank. One disc (black) is a ratchet wheel with conventional saw teeth and the other disc behind the ratchet contains six pawls, which can rotate on cylindrical joints and are acted upon by both gravity and centrifugal accelerations, when the disc rotates. For low speeds, the top pawls fall under gravity and lock the two discs together. For higher speeds, the centrifugal forces rotate the pawl tips away from the teeth of the ratchet wheel and de-couple the two discs.

Francis Moon 2004-07-00

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