Abstract: An assembled camshaft (10) for engine includes: a cam lobe piece (12); and a hollow shaft member (11) having at least two shaft fixing surfaces (11A) formed by plasticity process on a portion of the hollow shaft member (11) corresponding to a position between cylinders of the engine.

Abstract: A method of producing a cam lobe piece of an assembled camshaft in a valve operating system for an internal combustion engine. The method comprises (a) forming a profile of the cam lobe piece by upsetting a material under forging to obtain an intermediately formed body; (b) piercing a central portion of the intermediately formed body to form a shaft bore; and (c) ironing an inner peripheral surface of the pierced intermediately formed body to form unevenness at the inner peripheral surface, all accomplished by cold working. The material at the forming the profile of the cam lobe piece has a first section located on a side of a cam nose of the cam lobe piece, and a second section located longitudinally opposite to the first section. The material has a thickness which gradually increases in a direction from the second section to the first section.

Abstract: A bevel gear 1 has a radius of curvature R of a fillet curve provided between a tooth flank A and a bottom land B gradually increasing from a small-diameter end D1 to a large-diameter end D2.

Abstract: An assembled camshaft (10) for engine includes: a cam lobe piece (12); and a hollow shaft member (11) having at least two shaft fixing surfaces (11A) formed by plasticity process on a portion of the hollow shaft member (11) corresponding to a position between cylinders of the engine.

Abstract: A method of producing a cam lobe piece of an assembled camshaft in a valve operating system for an internal combustion engine. The method comprises (a) forming a profile of the cam lobe piece by upsetting a material under forging to obtain an intermediately formed body; (b) piercing a central portion of the intermediately formed body to form a shaft bore; and (c) ironing an inner peripheral surface of the pierced intermediately formed body to form unevenness at the inner peripheral surface, all accomplished by cold working. The material at the forming the profile of the cam lobe piece has a first section located on a side of a cam nose of the cam lobe piece, and a second section located longitudinally opposite to the first section. The material has a thickness which gradually increases in a direction from the second section to the first section.

Abstract: A bevel gear 1 has a radius of curvature R of a fillet curve provided between a tooth flank A and a bottom land B gradually increasing from a small-diameter end D1 to a large-diameter end D2.

Abstract: A pulley useable with a driving belt in a continuously variable transmission, including a moveable pulley half having an integral cylinder portion integrally formed therewith by plastic working. The moveable pulley half includes an axially extending hollow shaft portion, a radially outwardly extending flange portion having a contact surface frictionally contacted with the driving belt, and the integral cylinder portion axially extending at near an outer peripheral portion of the flange portion. The plastic working includes forming a workpiece, machining the workpiece, spinning the workpiece to form the integral cylinder portion, heat-treating the workpiece and finishing the workpiece to complete the moveable pulley half.

Abstract: A method of producing a disc of an automotive road wheel by using an aluminum alloy as a material. The producing method comprising the following steps: (1) casting a disc material including an annular spoke section which has a ridge and is formed with a depression, the depression defined by a bottom wall; and (2) forging the disc material to obtain the forged disc by applying a processing degree of not less than 15% to the bottom wall of the spoke section and by applying a stress of not less than 50 MPa to the ridge of the spoke section.