Ratchet is a gear with a rigid toothed surface or a friction surface on the outer or inner edge and is an important component of the ratchet mechanism. The stepping motion is performed by the pawl pushing action, and the meshing motion is characterized in that the ratchet can only rotate in one direction, but cannot be reversed.
When the active member rocker swings counterclockwise, the driving pawl is inserted into the tooth groove of the ratchet, and the ratchet is pushed through an angle, at which time the pawl slides on the back of the ratchet. When the active member rocker swings clockwise, the pawl prevents the ratchet from rotating in a clockwise direction, while the drive pawl can slide over the back of the ratchet tooth, so that the ratchet is stationary. Thus, when the rocker makes a continuous reciprocating swing, the ratchet performs a one-way intermittent motion. Wherein, the reciprocating swing of the active member can be obtained by a swinging follower cam mechanism, a crank rocker mechanism, or by a hydraulic transmission and an electromagnetic device.
