Nissan Motor Company Limited

Nittan Valve Co., Ltd.

Shinji Fushimi

Takashi Matsumoto

Toshifumi Hibi

Nobuo Kino

Shunzo Umegaki

Kiyoshi Ohkawachi

Tetuo Tukamoto

Mitugu Kojima

Tetsuo Tsukamoto

Kiyosi Okawachi

A method of manufacturing a traction roller for a continuously variable transmission comprises placing a layer on a hollow cylindrical material having the volume substantially equal to the traction roller, performing axial pressure forging of the cylindrical material to obtain a work having the axial length substantially equal to that of the traction roller, performing axial die forging of the work to form side wall and outer peripheral surface of the traction roller, and grinding the work subjected to die forging to obtain a finished product of the traction roller.

Method of manufacturing traction rollers for continuously variable transmissions and traction rollers resulting therefrom

Method of manufacturing traction rollers for continuously variable

A method of producing a bevel gear is provided. The method comprises the steps of forging, from a case hardened and heated blank, a rough shaped bevel gear intermediate product having a toothed portion, outer burrs at a larger diameter end thereof and between adjacent teeth of the toothed portion, and a ring-shaped inner burr in a center hole thereof, setting the rough shaped bevel gear intermediate product in a trimming die during the time the rough shaped bevel gear intermediate product remains in an elevated temperature condition due to heat left therein after the step of forging, and trimming the outer burrs, and moving, after the step of trimming, the rough shaped bevel gear intermediate product from the trimming die to a sizing die in the vicinity of the trimming die and warm sizing the toothed portion in succession to the step of trimming.

Method of producing bevel gear

A hardened surface layer is formed in the region of inner and outer surfaces of a hollow material having a central through hole, then the hollow material is hot-forged into a hollow gear-like forged body by a forging die having a first die element with a piercing punch entering into the central through hole of the hollow material from one side thereof and having a second die element with a piercing punch entering into the central through hole of the hollow material from another side thereof. The forging die forms teeth of the gear on the outer side of the hollow material while producing an annular flash in the central through hole of the hollow material between the piercing punches. A distance between the piercing punches in a closed condition of the forging die defines a thickness of the annular flash which is 0.3 mm or more and no greater than 1.3 times (130%) of a depth of the hardened surface layer. After that, the annular flash is removed from the forged body, and thermal refining is implemented to the forged body by quenching and tempering.

Method of, and apparatus for manufacturing a gear with a central through

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Yokosuka, Japan

Shinji Fushimi