Pulleys 1, 2 and 3 are of equal diameter. The axis of slot b of slider 4 is parallel to line BC and perpendicular to the axes of guides p-p. Pulley 1 rotates about fixed axis A and, through flexible link 5, rotates pulleys 2 and 3 about fixed axes B an C. Pin a of flexible link 5 slides along slot b of slider 4 which moves in fixed guides p-p. When pulley 1 rotates about axis A, slider 4 reciprocates in guides p-p. When pin a travels along straight portion df of its path, slider 4 has a dwell in its right-hand extreme position.
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