Four-bar linkage ABCD is connected by turning pair C to link 1 which imparts reciprocating motion to gear rack 2. The rack stroke can be varied by changing the position of point D with screw E. Rack 2 meshes with gear 4 which rotates about fixed axis F. Rigidly at tached to gear 4 is member a which is connected by a turning pair to pawl 5. When rack 2 travels to the right, pawl 5 turns ratchet wheel 3 clockwise about axis F, independently of the rotation of gear 4.
$1827$LR,ML$