Abstract: The invention relates to a piston for internal combustion engines comprising a lower part which forms the shaft area and also comprising a piston upper part which is connected thereto by means of expandable screws and which forms the bottom and a ring area wherein the expanding screws in the piston upper part (1) are disposed on pressure pieces engaging in the respective bores in the lower piston part (1) and wherein the respective disposition between the pressure piece and the lower piston part (1) occurs via inclined adjacent surfaces. The aim of the invention is to invent a piston which is easy to produce, which in relation to prior art enables improved introduction of forces for the connection of the piston part to the piston.

Abstract: A piston-pin bearing for an internal combustion engine wherein a cylindrical piston pin is mounted. The piston-pin bearing has a hub bore that significantly reduces mechanical stress in the piston, results in a longer service life for the piston, and avoids the formation of noise in the piston-pin bearing. Thus hub bore has a lateral surface with a highly oval shape along the axis of the hub in the equatorial-zenith-equatorial area, corresponding to the parameter representation of an oval that follows x=b/2×cos ?; y=a/2×sin ? for 0°???180°. The hub bore has a circular cylindrical shape in the equatorial-nadir-equatorial region of the hub, whereby a is a large oval diameter; b=D is a small oval diameter; D is a diameter of the cylindrical hub; and ? is the angle forming any particular unlimited line counter to the z axis.

Abstract: The invention relates to a piston for internal combustion engines comprising a lower part which forms the shaft area and also comprising a piston upper part which is connected thereto by means of expandable screws and which forms the bottom and a ring area wherein the expanding screws in the piston upper part (1) are disposed on pressure pieces engaging in the respective bores in the lower piston part (1) and wherein the respective disposition between the pressure piece and the lower piston part (1) occurs via inclined adjacent surfaces. The aim of the invention is to invent a piston which is easy to produce, which in relation to prior art enables improved introduction of forces for the connection of the piston part to the piston.

Abstract: The invention relates to a piston-pin bearing for an internal combustion engine wherein a cylindrical piston pin (8) is mounted. The inventive piston-pin bearing is provided with an improved form of hub bore in comparison with prior art, significantly reducing mechanical stress in said piston and therefore resulting in a longer service life for said piston. Said form also avoids the formation of noise in the piston-pin bearing. According to the invention, this is achieved by providing the lateral surface (5) of the hub bore (2) with a highly oval shape along the entire axis of the hub in the equatorial-zenith-equatorial area of said hub, corresponding to the parameter representation of an oval x=b/2×cos }; y=a/2×sin}for 0o==180o, and by providing it with a circular cylindrical shape in the equatorial-nadir-equatorial region of the hub, whereby a: large oval diameter; b=D: small oval diameter; D: diameter of the cylindrical hub; : the angle forming any particular unlimited line counter to the z axis.