| 摘要 |
PURPOSE:To produce respective parts with good productivity and good accuracy by shearing and separating a blank material before forging which is molded integrally with the parts to be made into a connecting rod and a cap to said parts with a sintering and forging die and sintering and forging the respective parts. CONSTITUTION:Raw material powder is compression-molded with a plunger die and is sintered in an ordinary way, whereby a blank material 3 before forging having the shape wherein the parts 1A, 2A to be made into a connecting rod and a cap are united to one body is formed. The material 3 is set, as shown in the figure, in a sintering and forging die 9 wherein the upper and lower punches 11 and 16 divided to punches 11 and 12, 15 and 16 having different descending strokes are held afloat by means of springs 14, 18. When the punches 11, 12 are lowered, the part 1A is held by the punches 11, 15, and the part 2A which is sandwiched by the punches 12, 16 descends in this state and is sheared and separated from the part 1A. The rolling force of the punches 11, 12 acts directly on the parts 1A, 2A thereafter and therefore said parts are compressed and are then sintered and forged. The resulting connecting rod part 1 and cap part 2 are subjected to post working. |
