Patent ID: 7926636
Filing Date: 2011-04-19
Classification: F16D

Abstract:
1. A twin clutch apparatus comprising: a pair of clutches disposed between a crankshaft and a transmission unit, the pair of clutches being operable to selectively engage or disengage transmission of a rotational driving power from the crankshaft to the transmission unit; the pair of clutches being arranged side by side on a shared axial line, each of the pair of clutches including at least one friction plate having a plurality of protruding portions protruding in a radial direction on an outer circumferential edge thereof; and a clutch outer member shared by the pair of clutches, the clutch outer member being a cylindrical member having an open-end side, and a closed end portion defining a closed-end side, the clutch outer member having a central axis and an inner wall surface which, as seen in cross-section, extends in a direction substantially parallel to the central axis; the clutch outer member having a plurality of groove portions formed in an internal circumferential surface thereof, said groove portions extending in an axial direction of the clutch outer member, wherein: said at least one friction plate is operable to engage with the clutch outer member by engaging the protruding portions thereof with the groove portions of the clutch outer member, with a clearance formed therebetween such that said at least one friction plate is operable to move in the axial direction and is inoperable to rotate independently of the clutch outer member; each of the groove portions of the clutch outer member is formed with a tapered shape having a variable width in a circumferential direction of the clutch outer member, wherein the width of the groove gradually increases in the circumferential direction as the groove extends from the closed-end side towards the open-end side thereof; one of the pair of clutches is disposed on the open-end side of the clutch outer member, and the other of the pair of clutches is disposed on the closed-end side of the clutch outer member, and a width in a circumferential direction of each of the protruding portions formed on said at least one friction plate of the clutch disposed on the open-end side is greater than a width in a circumferential direction of each of the protruding portions formed on said at least one friction plate of the clutch disposed on the closed-end side.