Patent ID: 7213337
Filing Date: 2007-05-08
Classification: B21J,B21K,F02B,F02F,Y10S,Y10T

Abstract:
1. A method of manufacturing an entire piston for internal-combustion engines comprising the steps of: (A) manufacturing initially a blank to constitute a piston by preliminarily forging along a first prescribed axis, and shaping specific contours on the forged blank to form a preliminarily-shaped piston; (B) at least one subsequent manufacturing step of forging the preliminarily-shaped piston along at least one other second axis for creating additional contours, said piston being formed by two separate forging steps, each of said steps having a different contour along a different axis; and boring through sides of said piston independent of the manufacturing steps (A) and (B) for receiving a sleeveless bolt; wherein said preliminarily shaped piston having a reducible wall thickness and reinforcements during the subsequent manufacturing step (B); and further including the step of shaping an integrated skirt in one of the two manufacturing steps (A) and (B) onto the preliminarily shaped piston, said skirt being shaped during the subsequent manufacturing step (B).