Abstract: The invention relates to a piston pin bearing of an internal combustion engine, in which a cylindrical piston pin is mounted. The aim of the invention is to create a hub bore shape that is improved compared to prior art in order to significantly reduce mechanical stress in the piston and thus extend the service life of the piston. Furthermore, the shape is to prevent noise from being generated in the piston pin bearing. The aims are achieved by the fact that the surface line of the highly oval outer surface, which runs in the zenith of the hub, extends at an angle to the hub axis from a radially outward point to a radially inward point on the piston side such that the greatest degree of ovalness defined by the oval diameter thereof is created at the respective inner ends of the hub bores and does not exceed a predefined value of the oval diameter.

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.