| 摘要 |
PROBLEM TO BE SOLVED: To provide a valve fitting part to be formed in a sheet metal body in a rocker arm which can be machined without generating any defects such as cracks or shrinkage. SOLUTION: A valve fitting part 11 of a body 5 is of inverted recessed shape through pressing one continuous wall 9 associated with the plastic flow. No defects such as cracks and shrinkage causing problems in an unreasonable die bending in a conventional practice are generated, and the variance in strength and accuracy in shape attributable to the defects can be eliminated. |
