Abstract: This engine structure includes: a cylinder block in which a cylinder bore is formed; a piston provided in the cylinder bore; a cylinder head provided to an upper portion of the cylinder block in a manner to seal the cylinder bore; and a ring that is inserted in the upper end portion of the cylinder bore and has an inner diameter that is smaller than the diameter of the cylinder. A first abradable layer that is worn down by contact with an outer peripheral surface of the piston is formed on an inner peripheral surface of the ring.

Abstract: Steering mechanisms for use in RSS systems may be devoid of an elastomeric piston seal. Pistons of the steering mechanisms have a convex cross-section that permit the piston to pivot along with a steering pad while moving laterally or radially along a piston axis defined by a piston bore. Hydraulic pressure may be maintained as the pad is extended since a limited gap size between the piston and the bore may be maintained throughout the motion of the pistons. The pistons may be retained to the steering pad in a T-slot and may be elongated in a direction orthogonal to the axis of the piston bore. A groove may be provided around the piston for a receiving a back-up seal therein. The back-up seal may include wear resistant balls embedded in a matrix, and balls may be preloaded to serve as flow restrictors even when worn.

Abstract: A piston ring is formed from a steel substrate consisting of the carbon in a range of 0.80-0.95 wt. %, silicon in a range of 0.30-0.55 wt. %, manganese in a range of 0.25-0.5 wt. %, phosphorus in a range of up to 0.04 wt. %, sulfur in a range of up to 0.04 wt. %, chromium in a range of 17-18 wt. %, molybdenum in a range of 0.70-1.25 wt. %, vanadium in a range of 0.05-0.15%, the remainder iron. The ring has been through hardened and tempered so that it has a hardness of 46-54 HRC. A coating is then applied via PVD or other suitable methods onto the ring surface to create the finished piston ring.

Abstract: Method for producing a piston ring having an axial height <2 mm, said piston ring having a radially outer running surface provided with at least one rail, a radially inner circumferential surface, and upper and lower flank surfaces extending therebetween, wherein said rail is provided with a contour that is tapered radially outwardly, thereafter the running surface, together with the flanks of the tapered rail, is provided with at least one wear-resistant layer, and then only the flank of the rail that is to form a scraping edge is subjected to at least partial material removal to form the scraping edge.

Abstract: The invention relates to a method for producing a piston ring (30, 130, 230) for a piston (10) of an internal combustion engine, comprising a ring back (31), an upper ring flank (32), a lower ring flank (33), and a running surface (42), and the method comprising the following method steps: (a) preparing a ring blank (30?) with a ring back (31?), an upper ring flank (32?), a lower ring flank (33?), and an outer lateral face (34?), (b) shaping an asymmetrical convex contour (35) along the outer lateral face (34?) and shaping a radially outward-extending protrusion (36) in the outer lateral surface (34?) in the region of the lower ring flank (33?), (c) coating the outer lateral surface (34?) with a coating material, (d) removing the protrusion (36), thereby exposing the material of the ring blank (30?) in the shape of a circumferential surface (41) which blends into the coating (39), and forming an oil scraper edge (40) between the circumferential surface (41) and the lower ring flank (33?), and (e) post and/or

Abstract: A method for producing a recessed steel piston ring provided with a wear-resistant layer includes generating a main body that has a recess on the running surface side and that, in the region where a lower flank of the main body transitions into the running surface is worked so that a chamfer is created, providing the running surface and at least portions of the chamfer with at least one wear-resistant layer, nitriding the circumferential surface and the lower and upper flanks of the main body that are not provided with the wear-resistant layer so that a section having a defined width and having no nitride layer remains on the flank adjacent the chamfer, and removing the at least one wear-resistant layer to such an extent that a substantially sharp, but unnitrided functional edge is created in the region where the lower flank transitions into the running surface.

Abstract: A piston ring is produced by providing a metallic main body, at least including a radially outer running surface, a radially inner circumferential surface and upper and lower flank surfaces interposed therebetween, with a defined taper in the region of an approximately cylindrical running surface, providing at least the running surface with at least one wear-resistant layer, and removing the at least one wear layer in the region of the entire circumference of the ring that forms a scraping edge forming a land having a predefinable width.

Abstract: Method for producing a piston ring having an axial height <2 mm, said piston ring having a radially outer running surface provided with at least one rail, a radially inner circumferential surface, and upper and lower flank surfaces extending therebetween, wherein said rail is provided with a contour that is tapered radially outwardly, thereafter the running surface, together with the flanks of the tapered rail, is provided with at least one wear-resistant layer, and then only the flank of the rail that is to form a scraping edge is subjected to at least partial material removal to form the scraping edge.

Abstract: A piston ring, is produced by providing, on the radially outer circumferential surface of a ring-shaped metallic main body, a recess, the metallic main body having a radially outer circumferential surface, a radially inner circumferential surface, and flank surfaces interposed therebetween providing the recess with a contour that deviates from a cylindrical shape at least on the bottom of the recess, providing at least one wear-resistant layer on the outer circumferential surface, including the recess, and at least partially removing an area of the at least one wear-resistant layer on the outer circumferential surface and including an area corresponding to a scraping edge, thereby forming a land having a predefinable width.

Abstract: Method for producing a piston ring provided with a butt joint, in that an annular metallic main body is provided with at least one hard layer at least in the area of the outer circumferential surface of said main body, wherein after this coating the inner circumferential surface of the piston ring is at least partially subjected to a wall-thickness-reducing material removal process.

Abstract: A piston ring is formed from a ring blank, e.g., a wire, that has a cross sectional profile including upper and lower surfaces that are generally parallel and disposed between inner and outer peripheral faces. The cross sectional profile also includes a hook area at the outer portion of the lower surface that includes a nose area. The nose area is provided with a radius that is as sharp as possible, and is disposed such that a grinding operation performed on the lower surface, e.g., with a single generally planar grinding surface, will also grind the nose area, thereby truncating the nose area and increasing sharpness of the nose area without having to perform additional machining operations.

Abstract: A piston for an internal combustion engine includes a one-piece aluminum piston body including a piston head and a piston skirt adjoining the head. The skirt includes a taper narrowing towards the head and defining a major diameter in a first direction normal to a longitudinal piston axis, and a minor diameter in a direction normal to the first direction. The major diameter and minor diameter may have dimensions specified in Table 1, such that scuffing or scratching of the piston is prevented, particularly during engine break-in.

Abstract: A piston ring, in particular a compression piston ring, includes a running surface, upper and lower flank areas, an inner peripheral area and a joint. The wall thickness of the piston ring is uniform over its periphery and at least the running surface is provided with a PVD coating or a CVD layer in such a manner that the running surface layer has a lesser layer thickness in the peripheral area close to the joint than in the remaining peripheral area of the running surface.

Abstract: A method is provided for efficiently manufacturing a high quality internal combustion engine piston having an annular cavity allowing for good circulation of cooling fluid. An annular groove is formed at the circumferential edge of the top face of a piston crown, or at the top of the exterior circumferential face of the crown, and an annular protruding strip is formed as a continuation of an edge of the opening of the annular groove. The protruding strip is bent in the direction of the opening of the annular groove by bringing to bear a pressure roller 11, while rotating the main piston body. Consequently, the opening of the annular groove is closed, whereby an annular cavity for circulating cooling fluid is formed so as to surround a pressure receiving recess.

Abstract: The invention relates to a method for producing a coat on the outer peripheral surface of a piston ring base. According to said method, a plurality of layers is applied layer by layer to the peripheral surface by applying, using a PVD method, at least one metal adhesive layer based on Cr to the peripheral surface without adding nitrogen to the process gas. Nitrogen is added to the process gas while increasing the partial pressure of the nitrogen, thereby forming a CrN gradient layer on the adhesive layer, and finally at least one cover layer having a constant composition based on CrN, Cr2N or a mixture of the two phases is applied to said gradient layer.

Abstract: The invention relates to a method for producing a cooled ring carrier (1) for an aluminium piston pertaining to an internal combustion engine and produced according to a casting method, comprising a cooling channel (6) which is embodied on the rear (3) of the ring carrier as a downwardly open turned groove (4) According to the invention, salt granules are pressed into the turned groove (4) at a pressure of between 100 and 300 N/mm2, in such a way that a salt core (5) is formed in the turned groove (4) The composite consisting of the ring carrier and the salt core is then immersed in an alfin bath.

Abstract: The invention relates to a wear-resistant coating used for bearing surfaces and flanks of piston rings in internal combustion engines. The wear-resistant inventive coating is obtained by mechanically alloying powders which form a metallic matrix with hard material dispersoids and lubricant material dispersoids. The coating is then thermally applied to the workpieces, especially by means of high velocity oxygen fuel spraying (HVOF). The workpieces coated are bearing surfaces and parts of flanks pertaining to piston rings in internal combustion engines.

Abstract: Aggressive property of the nitrided side rails (30), which are combined with a spacer expander (31) to construct the oil-control ring, against the opposing material is improved. A nitriding layer consisting of nitrogen diffusion layer is formed on the outer peripheral surface or inner and outer peripheral surfaces of side-rail steel. The surface is free of compound layer. Hard grain-boundary phases (intergranular phases) are not present at least in the surface region of the side rail.

Abstract: A wear resistant coating for protecting surfaces undergoing sliding contact is disclosed. The wear resistant coating is applied by high velocity oxygen-fuel (HVOF) deposition of a powdered blend of the coating constituents. The powdered blend includes a nickel-chromium alloy, chromium carbide, and molybdenum. The disclosed coating should find use as a bearing surface on piston rings, cylinder liners, and other components of a power cylinder assembly of an internal combustion engine.

Abstract: In an electrodeposited hard-chromium coat, particularly for a piston ring, which is substantially formed of an electrolyte containing hexavalent chromium, wherein there are cracks in the coat and diamond particles are embedded in these cracks, the diamond particles have a size ranging from 0.25 to 0.5 &mgr;m.

Abstract: A brake (10) for a hydraulic vehicle brake system has a housing (14) with a bore (18) which is formed therein and in which a brake piston (20) is received in a sealingly and slideably displaceable manner. The brake piston (20) is adapted to press a brake lining (32) against a brake disk (12) by way of hydraulic pressure. For sealing, the brake piston (20) is sealed off relative to the bore (18) by a sealing ring (26) made of elastic material. In order to optimize the adhesive and sliding properties between the sealing ring (26) and brake piston (20), the sealing ring (26) and/or at least that outer surface of the brake piston (20) which cooperates with the sealing ring (26) is coated with a lacquer which contains an organic binder and a solid lubricant.

Abstract: A method of making an oil scraper piston ring includes the following steps of providing a base ring body including a circumferential web having flanks and an outer circumferential surface; galvanically depositing on the web a wear resistant hard chromium layer having solid particles embedded therein; applying a break-off resistant cover layer to the hard chromium layer; and grinding the cover layer to provide the outer circumferential surface of the web with sharp bounding edges

Abstract: A wear resistant coating for protecting surfaces undergoing sliding contact is disclosed. The wear resistant coating is applied by high velocity oxygen-fuel (HVOF) deposition of a powdered blend of the coating constituents. The powdered blend includes a nickel-chromium alloy, chromium carbide, and molybdenum. The disclosed coating should find use as a bearing surface on piston rings, cylinder liners, and other components of a power cylinder assembly of an internal combustion engine.