Patent attributes
In a friction plate 40, segment pieces 42 of a friction material are bonded onto a core plate 40 at intervals in a circumferential direction. 43 denotes a spline tooth. On each segment piece, there are formed a first oil groove which is made to open to an inside-diameter side of the segment piece and has its end portion part-way along the segment piece (hereinafter, referred to as a first oil groove) and a second oil groove which is made to open to an outside-diameter side of the segment piece and has its end portion part-way along the segment piece (hereinafter, referred to as a second oil groove). Segment pieces in which a first oil groove 51 and second oil grooves 61 are pressure molded and segment pieces in which a first oil grooves 52 and second oil grooves 62 are stamped are arranged alternately.
