Piston for internal combustion engines

Claim 1

A piston with a piston bottom for internal combustion engines, especially high output internal combustion engines, in which the peripheral surface of the piston is provided with a plurality of annular groove means, and which comprises piston ring means respectively arranged in said annular groove means, the peripheral surface of said piston also being provided with recess means for receiving and storing lubricating oil, said recess means being open only toward the outside of said piston and being completely separated from neighboring groove means and located between that one of said groove means which is nearest to said piston bottom and the groove means nearest to said last mentioned one of said groove means, that annular groove means which is nearest said piston bottom being formed by an annular piston ring carrier inserted into and firmly seated in said piston, said ring carrier including a single ring groove therein and having its outer peripheral surface substantially flush with the adjacent peripheral surface of said piston being formed by a shrunk ring shrunk onto said piston and of a material having a coefficient of heat expansion corresponding substantially to that of said piston, said shrunk ring being shrunk upon said piston with slight overlap, said recess means including parallel walls being at right angles to the peripheral surface of the piston with the depth of the recess means corresponding to the depth of remaining groove means and being worked directly into the peripheral surface of the piston, said recess means being located between said ring carrier and the groove means next to said ring carrier, and a top land between said piston bottom and the groove means adjacent thereto, said top land being as short as possible.