Crankshaft Patents (Class 29/38E)
  • Patent number: 4969262
    Abstract: A method of making a camshaft of the type having a cam piece composed of outer and inner layers which comprises the steps of molding a green cam piece in a manner that the outer and inner layers are respectively made from powders of outer-layer and inner-layer forming materials, fitting the green cam piece on a steel shaft to produce a green camshaft assembly, and sintering said green camshaft assembly at a temperature in which the materials shrink and yield a liquid phase to produce a camshaft having a cam piece diffusion-bonded to the outer periphery of the shaft.The outer-layer forming material is prepared to have an axial shrinkage of 4 to 10% and shrink more than said inner-layer forming material prepared to have an axial shrinkage of 2.5 to 6%.
    Type: Grant
    Filed: March 20, 1990
    Date of Patent: November 13, 1990
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Takeshi Hiraoka, Shunsuke Takeguchi, Satoshi Kawai