| 摘要 |
PURPOSE:To remove the casting defect of a sliding part and to improve the mechanical property, especially the wear resistance by executing the plastic work of a form rolling, etc. in the state of the temp. up of the flange part of a cast stock and forming the sliding part extending in the axial direction in smaller diameter than that of the flange part. CONSTITUTION:In order to make the cam shaft of an engine, the stock 11 in about a shaft shape having a flange part 11a is made by casting first. A form rolling (plastic work) is executed on the flange part 11a after holding the outer peripheral part of the flange part 11a of this stock 11 for a fixed time by rising the temp. to the prescribed temp. using a high frequency heating device, etc. This form rolling is performed by arranging the flange part 11a between the upper die 12a and lower die 12b and moving the dies 12a and 12b in reverse direction. The outer peripheral edge of the flange part 11a is reduced with its deformation in the axial direction by this form rolling and the preform of a cam 13a is formed. The prescribed heat treatment is performed in succession after executing the machining of a grinding, etc. |
