Abstract: A light alloy piston for internal combustion engines has a skirt which is closed at its lower end and at locations disposed adjacent to the bosses on both sides of the horizontal plane through the piston pin is set back so as to form respective recesses. In order to avoid a retention of oil in the recesses those end portions of the skirt which adjoin the recesses are inwardly offset from the outside peripheral surface of the piston.

Abstract: A one-piece piston is produced by die pressing in a single step, a previously forged blank to bend an annular cylindrical collar thereon and at the same time form a fire rib between two lugs which are pierced in the die-pressing tool so that eyes are formed in the lugs and the latter are calibrated by the piercing operation.

Abstract: A cast aluminum piston for internal combustion engines having mechanically compacted inner boss bore faces, the structure of the aluminum material disposed below these inner faces having a grain pattern orientated in the circumferential direction of the boss bore over a radial depth of at least 0.1 mm and preferably 0.2 mm. This grain pattern is achieved by rolling at a temperature of at least 350 degrees C. up to 400 degrees C. with simultaneous expansion of the bore diameter by about 0.2 to 0.5 mm.

Abstract: A piston for internal combustion engines, which has inclined surface portions in the skirt area to allow formation of hydrodynamic wedges of lubricant, these surface portions being constructed as skirt recesses (13 or 14) which are open either towards the upper or towards the lower end of the piston skirt. The transition zone from these skirt recesses to the bearing surface of the working surface of the piston is constituted by oblique surfaces which are inclined inwardly from the surface of the skirt. The oblique surfaces terminate in a circumferential direction within the bearing surfaces of the piston. The oblique surfaces constitute ramps on which a hydrodynamic wedge of lubricacting oil can form.

Abstract: A piston ring and piston assembly designed for operation with the piston skirt fully flooded with oil and with the piston rings operating as fully hydrodynamic sliders is disclosed. Geometries of rings and piston skirt are arranged to conform elastically to the real out-of-round deformations of cylinder walls in such a fashion as to maximize the advantages of full film lubrication physics. The rings are loaded in circumferential compression and are flexible. This elastic configuration makes the rings conform instantaneously to cylinder wall out-of-round to a scale of microinches. This conformability is required to maintain oil control (zero oil pumping to the top of the cylinder wall) with fully hydrodynamic conditions between the rings and the cylinder wall. The piston has a piston skirt which is flexible enough to conform to cylinder wall out-of-round and maximize squeeze film effects. The piston skirt is arranged to superimpose squeeze film and pivoted pad slider physics.

Abstract: A piston for internal combustion engines, especially for motors of the Diesel type. On purpose to reduce the heat diffusion from the piston crown to the piston portion where are fitted the sealing piston rings, provision is made of an internal circular groove intended to reduce the thickness of the connection portion between the piston crown and the side portion where are fitted the sealing rings, an external cut tangentially formed in the piston side portion substantially at the connection thereof with the piston crown, i.e. above the grooves of the piston rings, being substituted for the circular groove which is interrupted below the regions of the piston crown provided with any recess which would cause the thickness of the connection portion to be too slight.

Abstract: An automotive diesel engine is provided with pistons which carry two compression rings and an oil control ring in the conventional manner, the cold end clearance of the second compression ring being greatly exaggerated compared to the cold end clearance of the top compression ring and the annulus defined by the second land of the piston, the two compression rings and the engine cylinder wall having an empirically determined volume, preferably in the range of about 0.12 cubic inches to about 0.35 cubic inches. The top land of the piston is preferably set back to provide exaggerated diametrical clearance with the cylinder wall.

Abstract: A process for making a light-weight, heavy duty steel piston for a disc brake. The initial blank is formed to include the piston nose radii and angle. The blank is then simultaneously rolled by three rollers, one of which rollers forms the piston boot groove, another of which rollers maintains the outer diameter of the main portion of the piston, and the other roller of which forms near the outer end of the piston an overall diameter which is less than the main overall diameter. During the rolling step, the metal deforms to form a contour opposite the base of the piston boot groove such that the thickness of the wall between the contour and the base of the piston boot groove is smaller than the thickness of the main portion of the wall, but yet is strong enough to withstand heavy duty disc brake operation throughout the life of the disc brakes.

Abstract: A piston includes a plurality of pockets formed in the piston top face and opening through the piston sidewall. An arcuate relief is associated with each pocket and formed in the sidewall to overlap the pocket opening. The depth of the relief is relatively greater than the depth of the pocket.

Abstract: An improved piston construction comprising a piston body having a crown and a depending skirt, a peripheral groove about the body intermediate the crown and the skirt closely adjacent the crown, a grooved insert band in the groove and adapted to receive at least one piston ring, and at least one frustoconical washer in the groove abutting the insert band on the side thereof closest the crown, the washer having its minor base directed toward the skirt and its major base directed toward the crown and being stressed into a substantially planar configuration to store energy to tightly clamp the insert band within the groove to preclude loosening of the band during operation of an engine employing the piston. Also disclosed is a method of fabricating the improved piston construction.

Abstract: A seal for use within the interior portions of a piston, primarily on a diesel engine which has a pressurized oil supply which is forced upwardly through the connecting rod and sprayed on to the upper portion of the piston. The seal substantially closes the area between the connecting rod and the interior sidewalls of the piston skirt. The oil is thus restricted in flow, building up pressure within the top portion of the piston and causing the oil to contact the upper interior portion for cooling the piston and further, forced to lubricate the bushings on the wrist pin.

Abstract: A seal for use within the interior portions of a piston, primarily on a diesel engine which has a pressurized oil supply which is forced upwardly through the connecting rod and sprayed on to the upper portion of the piston. The seal substantially closes the area between the connecting rod and the interior sidewalls of the piston skirt. The oil is thus restricted in flow, building up pressure within the top portion of the piston and causing the oil to contact the upper interior portion for cooling the piston and further, forced to lubricate the bushings on the wrist pin.