Abstract: The aim of the invention is to produce a rounding off on a diesel piston comprising a combustion recess and valve recesses that lie at a slant in relation to the piston floor. The rounding off should not significantly increase particle emissions. To this end, the edge of the recess is rounded off in the area of the valve recesses in a special machining phase, the cutting edges of the cutting tool being guided in one or more planes that are parallel to the inclined valve recess surface.

Abstract: A light metal cylinder liner with a surface which facilitates the connection with the surrounding cast material may be produced. The cylinder liner is produced by a lost-foam method with a form for production of the cast foam model having a structured surface with height variations of 0.8 to 5 mm. The structured surface is, for example, grooves or longitudinal elevations.

Abstract: The invention relates to a piston for an internal combustion engine comprising piston-pin bores, into which lubrication grooves that run around the nadir and equator zones of said bores are machined. The aim of the invention, is to simplify the production of the piston-pin bores provided with said lubrication grooves. To achieve this, each of the lubrication grooves has a central region, whose groove base has a depth of less than 100 ?m. Said central region is flanked by groove areas facing towards the interior and exterior of the piston. The bases of said grooves are inclined towards the longitudinal axis, each forming an acute angle with the longitudinal axis of the piston-pin bore.

Abstract: The invention relates to a cooled piston (1) for an internal combustion engine comprising a cooling duct (2). This cooling duct encircles in an annular manner inside the piston head at the height of the ring part and is closed at its end, which is open toward the piston skirt, by men of a spring part (8). Said spring part is correspondingly shaped, is radially divided at least once on the periphery thereof, and provided with a cooling oil inlet (5). The aim of the invention is to achieve an improved location-dependent removal of heat from the particularly hot portions of the piston (1). To this end, an encircling oil guiding ring (3) is placed inside the cooling duct (2) and, from the cooling oil inlet (5) to the cooling oil outlet (6), symmetrically divides the cooling duct (2) on the periphery thereof into sections (4) of different cooling duct volumes.

Abstract: A method for the production of pistons having depression edge armoring for internal combustion engines, in which a more heat-resistant armoring ring, in comparison with a forged piston blank having a combustion depression, is connected with the piston blank in the region of the depression edge. The method comprises the following steps: a first piston blank is set on a projection of the armoring ring in the region of the depression edge; the armoring ring is connected with the first piston blank by friction-welding; a second piston blank is set onto the projection of the armoring ring, in such a manner that the two piston blanks do not touch; the second piston blank is connected with the armoring ring by means of friction-welding; a the armoring ring is cut between the piston blanks, and the pistons are given their final shape by a cutting work method.

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: Cooled two-part piston for internal combustion engines having an upper piston part containing the piston ring grooves and piston pin bosses, and a piston skirt connected with the former exclusively by way of a piston pin. The upper piston part has a cooling oil annular channel that is open towards the piston skirt, into which channel the cooling oil is introduced, and discharged. There are collecting pockets attached at the upper end of the piston skirt, which faces the upper piston part. The pockets at least partially cover the cooling oil annular channel. When the engine and piston are arranged horizontally, a tub-shaped recess is provided in an interior bottom region of the piston skirt for accommodating cooling oil. The circumferential wall limitation of the recess is formed exclusively by a wall of the inside piston skirt.

Abstract: A one-piece piston for an internal combustion engine, having a ring-shaped cooling channel arranged in the outer region of the piston head, is proposed, which is closed off by a ring-shaped cooling channel cover structured towards the side of the pin bosses as a support element. This cooling channel cover comprises at least two arc-shaped cover elements the outer edge of which supports the pin-boss-side face of the ring wall.

Abstract: The aim of the invention is to produce a light-alloy bearing bush with a rough external surface. To achieve this, particles, which are subsequently surrounded in part by the molten metal, are applied to the surface of the casting mould. When the bearing bush is released from the mould, the particles remain in said bush and are subsequently removed from the bearing bush preform either mechanically or by being dissolved in liquid.

Abstract: A cooling channel cover for a one-piece piston of an internal combustion engine, the piston having a closed cooling channel that runs around inside the piston crown, at the level of the piston ring band, and a ring-shaped recess provided between the piston ring band and the piston shaft, wherein the piston shaft is connected with the piston hubs suspended on the piston crown. In such a piston, an easy to assemble cooling channel cover is achieved in that a one-piece, plastic spring steal ring, U-shaped in cross-section, having radially angled outer and inner shanks around the circumference, has at least one film hinge running around the circumference of the ring. The film hinge allows at least one radial deflection of at least one of the shanks, in such a manner that in order to close off the cooling channel, the shanks engage in a stepped conical recess on the inner edge of the cooling channel.

Abstract: A method for the production of a one piece piston for an internal combustion engine. The piston has a ring shaped cooling channel arranged in an outer region of a piston head. The channel is partially closed off by a circumferential projection structured as an oil groove. The piston is produced in a simple and inexpensive manner using a piston blank using cutting work such as lathing.

Abstract: A cooling channel cover for a one-piece piston of an internal combustion engine, the piston having a closed cooling channel that runs around inside the piston crown, at the level of the piston ring band, and a ring-shaped recess provided between the piston ring band and the piston shaft. The piston shaft is connected with the piston hubs suspended on the piston crown. In such a piston, an easy to assemble cooling channel cover is achieved by a one-piece plastic/spring steel ring that is U-shaped in cross-section, having a ring bottom and an outer shank around the circumference, molded onto the ring bottom and angled off radially to the outside, and an inner shank around the circumference, angled off radially to the inside.

Abstract: A cooling channel cover for a one-piece piston of an internal combustion engine, the piston having a closed cooling channel that runs around inside the piston crown, at the level of the piston ring band, and a ring-shaped recess provided between the piston ring band and the piston shaft, wherein the piston shaft is connected with the piston hubs suspended on the piston crown. In such a piston, an easy to assemble cooling channel cover is achieved by means of a one-piece plastic/spring steel ring that is U-shaped in cross-section.

Abstract: In a cooling channel piston for a diesel engine with direct injection, a reduction in the compression height is achieved while keeping the output the same or increasing it. The piston consists of at least two parts soldered to one another, one of which is a piston base body forged from steel, having a shaft, hubs, and a ring part, and second part of which, consisting of steel or a nickel-based material, comprises a combustion trough and at least a part of the piston head. The piston base body and the second part together from a cooling channel that can be filled with oil.

Abstract: The invention relates to a piston for a diesel engine comprising a combustion cavity. The piston crown and the cavity are plasma-sprayed with a coating. The aim of the invention is to produce the coating in a cost-effective manner. To achieve this, the layer thickness of the coating is uneven, being thicker in the border region of the cavity.

Abstract: To prevent, in a cooled ring carrier (1) for pistons, durinh Alfin bonding, the formation of oxides induced by air that escapes due to porous ring carrier material and, as a consequence, an impairment of the ring carrier bond. To this end, the cooled ring carrier, once the ring carrier part and the sheet metal part (3) have been linked, is subjected to negative pressure in a vacuum tank.

Abstract: To provide the pistons of internal combustion engines with profiled ring grooves in a simple manner. To this end, the profile is produced by laser beams.

Abstract: The invention relates to a built-up piston, comprising central screwing and a central cooling chamber. The aim of the invention is to reduce the flow resistance in the oil delivery area. To this end, means for transferring oil from the piston rod to the central cooling chamber are provided in the area of the screw head of the central screw connection.

Abstract: A cooling channel cover for a one-piece piston of an internal combustion engine, the piston having a closed cooling channel that runs around inside the piston crown and a ring-shaped recess between the piston ring band and the piston shaft. There is an easy to assemble cooling channel cover comprising a one-piece plastic/spring steel ring that is U-shaped in cross-section, having a ring bottom and an outer shank around the circumference, molded onto the ring bottom and angled off radially to the outside, and an inner shank around the circumference, angled off radially to the inside. There is a fist radial division having a mouth width (M) and a second radial division forming a first film hinge for radial deflection of one of the ring shanks and a second film hinge that permits at least one radial deflection of at least one of the radially angled shanks. In order to close off the cooling channel, the shanks engage in a stepped conical recess of on an inner circumferential edge of the cooling channel.

Abstract: A method for the production of pistons having depression edge armoring for internal combustion engines, in which a more heat-resistant armoring ring, in comparison with a forged piston blank having a combustion depression, is connected with the piston blank in the region of the depression edge.