| 摘要 |
PURPOSE:To forcibly cool a top wall part of a piston, by installing an oil sump part in an innerspace of a piston body. CONSTITUTION:An oil sump constituent member 10 is provided with an almost oval shelf plate part 12 having an oil sump cavity 11, one side leg piece part 13 bent to the other side from both side edge parts of this shelf plate part 12 and one more pair of leg piece part 14 bent to one side from both end edge parts of the shelf plate part 12. And, the whole body is formed as spring steel by a pressed with a metal plate having proper elasticity. With this constitution, a top wall part of a piston is forcibly cooled. |
