Abstract: Piston with a reinforcing insert, presenting a top face (11) with a recessed combustion chamber (12) provided with a lateral peripheral wall, defined by the annular insert (20), which presents an internal end face (24) with a radial extension (d.sub.1) that is substantially smaller than the radial extension (d.sub.2) of the opposite external end face (22) of the annular insert (20). The radial thickness of the insert (20) varies along the profile of its external peripheral face (23), in order to maintain a value necessary to meet the requirements of structural reinforcement of the piston (10), at the region where the insert (20) is applied.

Abstract: A two-piece, or articulated, piston assembly for internal combustion engines, comprising a head composed of a top portion and a pair of pin bosses integral with it, a skirt portion, and a wrist pin mounted in the pin boss holes. The pin bosses are secured to a member restraining lateral deformation of the pin bosses. The restraining member may be the wrist pin itself, or defined by a cylindrical hollow pin fastened to the pin boss holes and housing the wrist pin. The thus formed structure prevents deformation of the pin bosses toward the cylinder liner, thereby imparting a higher strength to the piston assembly.

Abstract: A sliding bearing of the type comprising a backing layer; an intermediate layer provided with internal peripheral grooved portions crosswise the bearing length and longitudinally spaced from each other; optionally, a diffusion or bonding layer on the grooved portions; and a sliding layer of a material softer than the material of the intermediate layer and filling the grooved portions. According to the invention, the grooves of the grooved portions have a depth and longitudinal spacing with uniform or variable dimensions, wherein at least one of the characteristics of depth and spacing is mandatorily variable. This design allows a selective distribution of harder material and softer material on defined portions of the bearing as a function of specific operating requirements.

Abstract: A method for manufacturing a piston for internal combustion engines, compressors and the like, comprising a head portion articulately connected to a separate skirt portion, wherein the skirt portion comprises a steel tubular part obtained by cutting, bending and closing of a piece of steel strip, the outer surface of said tubular part being covered by a layer of antifriction material bonded to said outer surface prior to the cutting, bending and closing of the steel strip.