Vibration isolator coupling

Claim 1

A torsional vibration isolator coupling for obtaining a substantially torsional vibration free output torque from an input torque having torsional vibrations, such as an input torque derived directly from an internal combustion engine, the coupling including, an input torque disc formed of rigid material and adapted to be coupled to an input torque shaft, an output torque disc formed of rigid material and adapted to be coupled to an output torque shaft, the two discs being parallel and coaxial with each other, an annular elastomer band on the two faces of each disc, each elastomer band being contiguous to the periphery of its respective torque disc and extending radially inwardly from said periphery, to thereby define four axially spaced elastomer bands, a first pair of which sandwiches a radially outermost portion of the input torque disc and a second pair of which sandwiches a radially outermost portion of the output torque disc, a rigid elastomer band separator disc axially intermediate the two torque discs and axially positioned between the two axially innermost elastomer bands, the rigid band separator disc being of substantially the same radial extent as the two elastomer discs which axially sandwich it, a rigid annular retainer, the annular retainer being in the form of a cylinder having rigid, radially extending flanges at its ends, said flanges contacting and abutting the two axially outermost elastomer bands to thereby axially clamp and axially compress the elastomer bands against the two torque discs, whereby at least four radially extending, elastomer to rigid member interfaces are defined.