Variable-stroke and frequency drive

摘要

A four-bar kinematic chain has an input member which includes a portion formed with a guide channel, an elongated output member that is pivoted intermediate its end portions, and a link member having one end pivoted to one end portion of the output member and another end portion provided with a sliding block received in the guide channel. A crank drive is connected with the input member for oscillating the same and the guide channel, to thereby effect oscillatory movement of the other end portion of the output member and concomitant movement of an element to which the other end portion is coupled. An arrangement is provided for arresting the sliding block at selected locations in the guide channel, to thereby permit a variation in the stroke and frequency of the movements of the other end portion of the output member.