Improved filtering pulley

Abstract

Filtering pulleys for an accessory transmission of an internal combustion engine have a hub, an annular crown provided with a profile configured to cooperate with a transmission belt positioned externally coaxial around an axis (A) to the hub and supported in rotationally free motion on the hub itself, and a filtering unit for transmitting the torque interposed between the hub and the annular crown. The filtering unit has a torsion spring, a carrier, and a torque limiting joint cooperating with each other to transmit a torque between the hub and the crown. The filtering pulleys can include a damping means carried by a member that is integral with one of the hub and crown and configured to provide variable damping according to the torque.

Dependencies are inferred from the claim text.