Foam lined propshaft

摘要

A shaft structure (20) has a longitudinally extending cavity and is configured to vibrate in response to the receipt of an input of a predetermined frequency such that at least two second bending mode anti-nodes are generated in spaced relation to one another along the longitudinal axis of the shaft structure. The insert members (204a,204b) are disposed within the longitudinally extending cavity and engage an inner wall of the shaft structure. Each of the insert members is located at a position that approximately corresponds to an associated one of the anti-nodes and has a density that is tailored to an anticipated displacement of the associated anti-node. A method for attenuating noise transmission from a vehicle driveline is also disclosed.