| 摘要 |
PURPOSE:To form a chilled layer of practically uniform depth on the surface of a cam part, by irradiating the cam surface from which the lift part and down part of a cam nose are previously removed by required amounts, respectively, with high-density energy heat. CONSTITUTION:A camshaft stock 1 is formed by casting so that it has a cam part 10 of prescribed shape, and further, it has an external shape formed by removing the lift part 11a and down part 11b of a cam nose by required amounts, respectively, from an external shape 10b in which machining allowance is added to a normal cam-profile shape 10a. The cam surface 11 of the stock 1 supported and rotated in an A direction is remelted by means of a laser beam 21 applied from a laser beam machine 2, so that a chilled layer is formed. By this method, the chilled layer of practically uniform depth can be formed on the surface of the cam part because the amount of removal at the time of finish working can be relatively minimized even if respective depths of remelting in the lift part 11a and down part 11b are reduced owing to the difference in the angle of heat irradiation. |
