| 摘要 |
PURPOSE:To reduce the weight of a shaft and man-hour by forming respectively the shaft core part and outside part of the shaft of a steel material and light metal, blanking a groove hole to the shaft core part and forging and blanking a hole communicating with the above-mentioned groove hole to the light metal. CONSTITUTION:A drawn steel material 10 having a rectangular section is pressed to form a shaft core member 16 having step parts 14, 15, a groove hole 12 and a hole 13. A drawn light metal material 11 of which the outside circumference consists of a plane 11a, a circular arcuate surface 11b and a recess 11c is cut to form an outside member 17. The members 17a, 17b are pressed to both surfaces of the member 16 and are driven and fixed into the respective holes to obtain an assembled material 18. The assembled plate 18 is inserted into dies and the light metal in the recess 11c is plastically flowed by a pair of punches to form side walls at both ends in the longitudinal direction of the recess 11c and to force the exess metal into the hole 12. The light metal in the hole 12 is press-blanked and a shaft 33 having a groove hole 24 for engaging a belt is obtd. The weight of the shaft and the man-hour for working are thus reduced. |
