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US 4,662,047 AGranted
Method of making a one-piece piston for an internal-combustion engine
AssigneeBerchem & Schaberg GmbH
InventorRutger Berchem
Life of this patent
Estimating the term…
Abstract
A one-piece piston is produced by die pressing in a single step, a previously forged blank to bend an annular cylindrical collar thereon and at the same time form a fire rib between two lugs which are pierced in the die-pressing tool so that eyes are formed in the lugs and the latter are calibrated by the piercing operation.
Claims5
A method of making a piston for an internal-combustion engine which comprises the steps of:
- die forging a blank of steel to produce a circular planar flange surrounding a recess into which a piston head projects at one side and having a pair of posts rising from an opposite side and flanking an axis of said blank;
- thereafter die pressing said blank in a single step to bend said flange into a substantially annular collar separated from said piston head by an annular gap restricting heat flow and connected to said head by a piston crown shoulder while forming at least one fire rib bridging said posts and shaping said posts to the final configuration of respective lugs adapted to swingably connect said piston to a piston rod;
- and
- in conjunction with said die-pressing operation, piercing said lugs to form respective eyes therein and simultaneously calibrating eyes.
1 more element
Dependencies are inferred from the claim text.