Torsionally resilient coupling for transmitting rotary motion

摘要

A power transmission mechanism for transmitting rotary motion performs two separate functions: It steps down the rate of rotation of an input shaft so that a rotatable member driven through the transmission mechanism rotates at a slower rate; and it also provides resilient energy storage so that the rate of rotation of the rotatable member can vary intermittently in response to load variations that are imposed upon it. A rotatable member that is to be driven has a cylindrical track secured to it. A roller frame carries three separate rollers which engage the track at spaced locations around its circumference so that the rotatable member is rotatable relative to the roller frame. A driven shaft is directly attached to one of the rollers so as to thereby drive the rotatable member. The driven shaft is rotatably supported from an associated housing. Spring means coupled between the roller frame and the housing allow intermittent oscillation of the roller frame relative to the housing, with the result that when the rotatable output member encounters variations in the load imposed upon it, its rotation may be temporarily retarded or advanced.