| 摘要 |
An object of the invention is to provide a pump tappet capable of bearing a large load from a pump plunger even if a case, which is a constituent member of the pump tappet, has a reduced thickness in its intermediate bottom. The invention thus contributes to reduced weight of the overall pump tappet. The case for the pump tappet is formed from an intermediary workpiece 40, which is made by means of a cold forging process of pressing a central region of a round steel material from both surfaces thereby pushing a portion of the material in the central region radially outward, forcing the material to flow axially in an up-down direction, so that an intermediate bottom 40c has a continuous fiber flow. |
