Method of producing a shaft having plate-like member joined thereto

A method of producing a cam shaft comprising the steps of:

• providing a plurality of cam pieces each of which comprises a cam face, a hole and first and second side faces perpendicular to a central axis of said hole;
• forming at least one annular groove in an inner surface of sai hole of said each cam piece;
• providing a plurality of annular projections on a shaft, the number of said annular projections corresponding to the number of said cam pieces to be mounted on said shaft, each of said annular projections slightly projecting from a circumferential surface of said shaft at an adjacent portion thereto, having an outer diameter substantially the same as or slightly less than an inner diameter of said hole of said cam piece, and first and second side faces on both sides of said annular projection;
• holding one end portion of said shaft;
• inserting said shaft into each of said cam pieces so that each of said annular projections faces an inner surface of the hole of said cam pieces;
• supporting one side face of said each cam piece so that said annular groove of said each cam piece is substantially between said first and second side faces of said annular projection of said shaft;
• and
• pressing substantially a whole area of said side face of said each annular projection so that part of said annular projection plastically deforms to flow into said annular groove.

A method of producing a cam shaft, comprising the steps of:

• preparing a shaft having a circular cross-section;
• forming annular projections on said shaft at the positions to which cam pieces are to be mounted, each of said annular projections, coaxially projecting from a circumferential surface of said shaft by a predetermined height so that the outer diameter of said each annular projection is larger than the circumferential surface of said shaft immediately adjacent to said annular projection, and having side faces spaced from each other by a width of said annular projection;
• preparing cam pieces to be mounted on said annular projections of said shaft, each of said cam pieces having a cam face at a circumferential portion thereof, a through hole, said faces one of which is perpendicular both to said cam face and to said through hole;
• forming at least one annular groove on the inner surface of said through hole at a position inside one of said side faces of said cam piece, said annular groove having a rugged surface therein;
• preparing a seat plate having an upper surface and a hole a central axis of which is perpendicular to said upper surface of said seat plate;
• supporting said shaft by said seat plate so as to be perpendicular to said upper surface of said seat plate;
• preparing receiving blocks the number of which corresponds to the number of said cam pieces to be mounted, said respective receiving blocks having height equal to respective distances of said cam pieces from said upper surface of said seat plate, each of said receiving blocks having a hole the diameter of which is larger than the diameter of said shaft immediately adjacent to said annular projections, and hollow portion, and being divided into two separate pieces;
• disposing one of said receiving block on said seat plate so as to surround said shaft;
• fitting one of said cam pieces on one of said annular projections of said shaft and resting said cam pieces on said receiving block;
• preparing a punch having an annular pressing face at one end and being divided into two separable pieces;
• pressing one side of said annular projection fitted with said cam piece to be mounted to plastically deform said one side, whereby part of said annular projection flows into said annular groove of said cam piece, and
• repeating said disposing step, said fitting step, and said pressing step with respect to the other each cam piece until all of said cam pieces are mounted on said shaft.