Patent ID: 7341267

Claim:
A reversible ratchet mechanism for converting a reciprocating motion of an actuating force to an intermittent unidirectional motion of a ratch, comprising: a lever adapted for reciprocating motion in relation to a support structure; means for alternatively coupling the ratch to the lever under a first condition of operation wherein the ratch is engaged during a first stroke of said reciprocating motion and is disengaged during an opposite second stroke, or under a second condition of operation wherein the ratch is disengaged during the first stroke and engaged during the opposite second stroke of the reciprocating motion; and means for selectively shifting between said first and second conditions of operation, wherein said lever is pivotally mounted on a frame adapted for said reciprocating motion in relation to a support structure; said means for alternatively coupling the ratch to the lever includes two roller clutches mounted on the lever, one roller clutch being freely rotatable clockwise and becoming locked when urged to rotate counterclockwise and the other roller clutch being freely rotatable counterclockwise and becoming locked when urged to rotate clockwise; and said one roller clutch engages the ratch during the first condition of operation and said other roller clutch engages the ratch during the second condition of operation; and further including an idle roller rotatably mounted on said frame opposite to each of said roller clutches to support said ratch when the ratch is engaged by either of the roller clutches.