US Patent 7210399 Two-part piston for an internal combustion engine

A two-part piston for an internal combustion engine has a piston head and a piston skirt. The piston head has a piston crown on the underside of which at least two boss lands, each provided with a head boss and a head boss hole are connected. The piston skirt has at least two boss bodies, each provided with a skirt boss and a skirt boss hole. When the head and skirt are joined, the head boss holes and skirt boss holes are flush in relation to each other for accommodating a gudgeon pin. Each boss body has a recess in which the corresponding boss land is accommodated with the associated head boss so that the head boss hole and skirt boss hole are aligned flush relative to each other.