Patent attributes
A clutch device includes an outer member including a cylindrical part having an inner peripheral surface provided with outer projections extending in an axial direction; an inner member rotatable relative to the outer member; an outer friction member engaging with the outer projections such that the outer friction member is movable in the axial direction and rotation of the outer friction member relative to the outer member is restricted; an inner friction member whose rotation relative to the inner member is restricted, and which generates a frictional force between the inner and outer friction members; and a lubricating oil sealed in a clutch chamber located between the outer member and the inner member. The outer member is provided with an oil pocket recessed to a position outward of a bottom surface of a recessed part located between a pair of adjacent outer projections among the outer projections.