Abstract: Two seal rings are provided comprising an upper ring and a lower ring, the rings having a common axis, a common outer cylindrical surface, a common inner cylindrical surface, and a couple of facing surfaces. The facing surfaces form an engaging length in a radial section of the rings having a radially outer end and a radially inner end, and the facing surfaces and the common cylindrical surface define a first wedge-shaped gap with a radially inward leading edge at the outer end. The inward leading edge is provided with a first angle in a range of 10 seconds to 1 degree and 30 seconds, and the outer end is spaced more from the common cylindrical surface than from the common cylindrical inner surface.

Abstract: A combined steel oil control ring is provided which has steel side rails and a steel spacer expander. The spacer expander includes ear portions for contacting the side rails. The ear portions are substantially equally spaced with respect to each other along the internal circumferential portion of the spacer expander. The ear portions have radially external circumferential surfaces adapted to press the side rails radially outwardly by using the resilient force caused by the spacer expander. The spacer expander has up-and-down contours formed circumferentially along the radially external circumferential surface, for preventing the side rails from circumferentially rotating relatively to the spacer expander. The up-and-down contours each include at least two axially extending groove regions and at least three axially extending flat regions. The groove regions and flat regions are dimensioned to extend the life span of the contours and the dies.

Abstract: A side rail is formed into a ring shape having its generally rectangular section that has an outer surface 3 formed with a pair of edge surfaces 5 of small radius, and an intermediate surface 6 of large radius of curvature formed between the edge surfaces 5. When the side rail is in the inclined condition in operation, each edge surface 5 can easily ride on oil film on cylinder 16 and allow the side rail 1 to perform smooth sliding movement on the inner surface of cylinder. The intermediate surface 6 efficiently scrapes lubricating oil on cylinder to form lubricating oil film of necessary and minimum thickness between an inner surface 17 of cylinder 16 and side rail 1. Also, the larger radius of curvature for forming the intermediate surface 6 provides a larger contact area to the inner surface 17 of cylinder 16 to improve wear resistance.

Abstract: A seal ring is provided, which is capable of maintaining a stable sealing performance for a long period, in which a cut portion is provided at one position in a circumferential direction of a seal ring, a convex portion is provided at a first cut end portion, a recess portion is provided at a second cut end portion, and the end portions of a third surface and a sixteenth surface extending in the circumferential direction among the convex portion and recess portion correspond to a portion of a second seal portion for sealing a side wall surface of an annular groove.

Abstract: A ring assembly, including a first oil scraper ring, a center oil scraper ring and a gas seal ring, adapted for disposition in a single groove of a packing cup which can be stationarily mounted over and around a reciprocally movable piston rod of a gas compressor. The function of the assembly is to both scrape lubricating oil from the piston rod for return to one side of the cup and to provide a seal against gas leakage from an opposite side of the cup, both along the piston rod under the seal ring and between the seal ring and opposing sides of the center ring and groove to prevent mixing of gas with the oil and escape of gas from the compressor. The center ring features a tapered outer peripheral surface portion. An annular side loading element, which can be a garter spring, is mounted in compression around the center ring so as to bear against the tapered surface portion and against an adjacent side of the first ring.

Abstract: A piston ring for the piston of a vibration damper includes a jacket and supporting segments connected to the jacket with holding surfaces. The supporting segments are supported axially on an upper side and a lower side of the piston by the holding surfaces. The piston ring has a seal carrier in which at least one seal is embedded, wherein the seal is oriented toward the piston proceeding from the seal carrier.

Abstract: The present invention provides a piston ring comprising a piston ring main body and an expander ring arranged on an inner peripheral surface thereof, the expander ring comprising two oil expander rings, one of which is housed in a space in a spiral of the other. The expander ring is formed so that the pressing force in the diameter expanding direction is larger in a high temperature state than in a low temperature state. The expander comprises two different kinds of expander members. One of these expander members has the same functions as those of a conventional expander, and the other is a member in which there occurs a change in tension in the diametral direction with temperature. As a result, the pressing force of the master expander member having the same effects as those of the conventional expander is made variable.

Abstract: A piston ring comprises a coating of a wear-resistant composite composition, particularly intended for high temperature applications. The wear-resistant composite composition comprises a ceramic compound and at least 50 volume %, based on the total volume of the wear-resistant composition, of an intermetallic nickel-aluminide chosen from the group consisting of NiAl and Ni3Al. A piston ring comprises a wear-resistant composite composition, particularly intended for high temperature applications. The wear-resistant composite composition comprises a ceramic compound and at least an intermetallic nickel-aluminide chosen from the group consisting of NiAl and Ni3Al.

Abstract: A two piece oil control ring is provided which comprises a ring body (1) formed into a generally M- or I-shaped section with an annular groove (4) on an inside surface (3) of the ring body (1); and a coiled expander (2) attached in the annular groove (4) of the ring body (1) for resiliently urging the ring body (1) toward an inner wall of a cylinder. The ring body (1) is made of stainless steel that contains chromium of 3.0 to 13.0 weight % with the outer and inner circumferential surfaces (11, 12) covered with nitrided layers (14, 15). Circular ratio (&tgr;) of an outer edge length (Yo) to an inner edge length (Yi) in the cross section of the ring body (1) is in a range between 1.08 and 1.32 to keep precise peripheral circularity of the ring body so that the nitrided layers survive lapping of the ring body (14, 15).

Abstract: A replacement torque converter clutch (TCC) apply valve for regulating the application of the torque converter clutch within an automatic transmission is disclosed. The TCC apply valve includes a valve piston having an expandable seal installed thereon at the primary wear location within a mating bore in the valve body to reduce hydraulic leakage. The valve piston also includes an internal fluid gallery formed therein in fluid communication with an annular groove wherein the expandable seal resides. Whenever the present TCC apply valve is actuated, TCC signal pressure enters the fluid gallery in the valve piston under pressure and simultaneously urges the expandable seal in a radially outward direction into contact with the mating bore to minimize hydraulic fluid leakage during the apply cycle of the torque converter clutch.

Abstract: The present invention provides a seal ring which can be prevented from being broken by an expansion and a shock applied thereto when the seal ring is fitted on a rotary shaft and does not have a configurative disadvantage such as a burr. Therefore no post-processing is required. The present invention also provides materials of the seal ring and a method of manufacturing the seal ring. The seal ring is made of resin and having two abutments confronting each other and a gate mark formed in an injection molding operation.

Abstract: A ring assembly, including a first oil scraper ring, a center oil scraper ring and a gas seal ring, adapted for disposition in a single groove of a packing cup which can be stationarily mounted over and around a reciprocally movable piston rod of a gas compressor. The function of the assembly is to both scrape lubricating oil from the piston rod for return to one side of the cup and to provide a seal against gas leakage from an opposite side of the cup, both along the piston rod under the seal ring and between the seal ring and opposing sides of the center ring and groove to prevent mixing of gas with the oil and escape of gas from the compressor. The center ring features a tapered outer peripheral surface portion. An annular side loading element, which can be a garter spring, is mounted in compression around the center ring so as to bear against the tapered surface portion and against an adjacent side of the first ring.

Abstract: A device for sealing a gap (7) between a first cylindrical part (2) and a second cylindrical part (5), in which the first cylindrical part (2) is received, includes a sealing ring (8) located in a circumferential groove (9) formed in the outer circumferential surface of the first cylindrical part (2), and at least one elastic element (10) located in the circumferential groove (3) for biasing the sealing ring (8) radially outwardly.

Abstract: An oil scraper piston ring includes an inner circumferential surface; an outer circumferential surface adapted to contact and slide along an inner wall of an engine cylinder; a radial wall thickness defined by a radial distance between the inner and outer circumferential surfaces; and a plurality of circumferentially distributed recesses each extending radially from the inner circumferential surface toward the outer circumferential surface to reduce the radial wall thickness. Each recess has a first recess region open at the inner circumferential surface and extending radially toward the outer circumferential surface and a second recess region merging into the first recess region. The two recess regions have different shapes, and the area of the second recess region is larger than the area of the first recess region.

Abstract: A piston ring includes a lateral surface which covers a circumferential surface of a piston and support segments with retaining surfaces which engage with the top and bottom of the piston. A piston ring joint allows the piston ring to be elastically deformed in the radial direction and is provided with a tongue at one end of the lateral surface, which tongue engages in an opening in the other end of the lateral surface. The tongue is designed with retaining segments which extend in the circumferential direction and continue as extensions of the support segments. The retaining segments engage supportively with the top and bottom of the piston. The opening is provided with carrier segments at least in certain areas of the circumference of the piston ring extensions of the support segments and holding the ends of the piston ring in place axially with respect to the piston-, the carrier segments being supported in the axial direction of the piston on the retaining segments.

Abstract: The invention discloses a piston ring comprising a piston ring substrate. The piston ring substrate comprises at least 50 volume %, of at least one intermetallic alloy, based on the total volume of the wear-resistant composition. The invention further relates to a piston ring comprising a wear-resistant composite composition and a piston ring coating comprising a wear-resistant composition, the wear-resistant composite composition comprising a ceramic compound.

Abstract: A piston ring for use in a cylinder of an internal combustion engine, which ring is nitride-hardened at least on the sliding surface between piston ring and cylinder wall. The nitride layer is composed of a precipitated layer and a compound layer, wherein the piston ring consists of a low-alloyed iron-base material and an oxide layer is deposited on the compound layer.

Abstract: Piston ring including a covering surface which covers a circumferential surface of a piston, and supporting segments having retaining surfaces which engage the upper and lower sides of the piston. The piston ring has a butt joint which enables the piston ring to be elastically deformable radially, the butt joint being designed at one end of the covering surface with at least one tongue which engages in a cutout in the other end of the covering surface. The tongue is designed with at least one retaining segment which runs in the circumferential direction and engages in a supporting manner in each case on the upper and lower side of the piston.

Abstract: A manufacturing method of a piston ring is developed, wherein the method provides a countermeasure for wear of butt ends of the ion plating film coated piston ring and a countermeasure for breakage of the piston ring and the piston ring manufactured at a low cost. A thickness of the film (2) in the vicinity of butt ends (7) of a piston ring (1) is made greater than the thickness of the film (2) at other outer peripheral surface. Piston ring blanks (5) are rotated around their own axes toward an evaporation source (4) and a speed is lowered when the butt ends (7) face the evaporation source (4).

Abstract: In order to increase in concentration of HC in an exhaust gas due to an axial gap between a ring groove and a piston ring, when an internal combustion engine is at a lower temperature, particularly, during the starting or the low-speed operation of the internal combustion engine in which the moving speed of a piston is lower, a restricting ring having a radially outward tension is inserted in a wedge shape into between axially opposed surfaces of a ring groove and a piston ring so that in a lower-speed operational range of a piston, the axial movement of the piston ring within the ring groove is restricted by the wedging action of the restricting ring, and in a higher-speed operational range of the piston, the wedging action of the restricting ring is removed by a floating force of the piston ring generated with the descending movement of the piston.

Abstract: A piston ring having a stainless steel base material, the base material having an upper surface, a lower surface, an inner circumferential surface and an outer circumferential surface, the surfaces each having a nitride layer formed thereon, the nitride layer each first being formed to have a compound layer and a diffusion layer, the diffusion layer of the outer circumferential surface then being exposed by removing the compound layer of the outer circumferential surface, the exposed diffusion layer thereafter having an ion-plating deposition layer of hard ceramic formed thereon, the piston ring wherein the exposed diffusion layer is entirely removed on the upper and lower corners of the upper and lower surface and the outer circumferential surface by chamfering corner regions of the nitride layer located around the upper and lower corners before the ion-plating deposition layer is formed.

Abstract: A two piece oil control ring is provided which comprises a ring body (1) formed into a generally M- or I-shaped section with an annular groove (4) on an inside surface (3) of the ring body (1); and a coiled expander (2) attached in the annular groove (4) of the ring body (1) for resiliently urging the ring body (1) toward an inner wall of a cylinder. The ring body (1) is made of stainless steel that contains chromium of 3.0 to 13.0 weight % with the outer and inner circumferential surfaces (11, 12) covered with nitrided layers (14, 15). Circular ratio (&tgr;) of an outer edge length (Yo) to an inner edge length (Yi) in the cross section of the ring body (1) is in a range between 1.08 and 1.32 to keep precise peripheral circularity of the ring body so that the nitrided layers survive lapping of the ring body (14, 15).

Abstract: A seal assembly with an accumulator ring for protecting a seal from explosive decompression is disclosed. The accumulator ring and the seal are contained within a seal gland. The seal is made of a material that is susceptible to damage from explosive decompression. When exposed to a high-pressure fluid environment, the accumulator ring fills with a quantity of high-pressure fluid, either by permeation if it is solid or by permeation and/or vents and/or channels leading to a void if it is hollow. During an explosive decompression event, the accumulator ring expands to fill the remaining volume of the seal gland. Then, the accumulator ring exerts an axial compressive or supporting force on the seal for a sufficient amount of time to allow the seal to expel fluid contained in it and minimize the effects of explosive decompression thereto.

Abstract: A contaminant pressure responsive, lubricant pressure amplified or modified rotary seal cartridge for rotary well pumps and other rotary mechanisms. A housing member having a passage subject to contaminant pressure, has a rotary wear sleeve which is supported by bearings and is sealed to the housing by a plurality of spaced seals which define at least one and preferably two or more lubricant chambers for bearing lubrication and for hydrodynamic sealing. Lubricant pressure amplification cylinders are in fluid communication with respective lubricant chambers. Pistons moveable within each of the cylinders define differential surface areas exposed to lubricant and to contaminant pressure. Contaminant pressure acts on the pistons and develops lubricant pressure which is different, preferably higher, but can be lower than contaminant pressure.

Abstract: The present invention provides a piston ring comprising a piston ring main body and an expander ring arranged on an inner peripheral surface thereof, the expander ring comprising two oil expander rings, one of which is housed in a space in a spiral of the other. The expander ring is formed so that the pressing force in the diameter expanding direction is larger in a high temperature state than in a low temperature state. The expander comprises two different kinds of expander members. One of these expander members has the same functions as those of a conventional expander, and the other is a member in which there occurs a change in tension in the diametral direction with temperature. As a result, the pressing force of the master expander member having the same effects as those of the conventional expander is made variable.

Abstract: Elastic sealing ring for sealing between a displaceable and/or rotatable component, such as a piston (2), piston rod (3), shaft etc., and a surrounding component, such as a cylinder block (1), a cylinder end wall etc. The sealing ring is adapted so as to be mounted in a groove in one component and has at least one sealing surface (28; 31, 32) intended for bearing against the other component, and comprises two materials with different properties. The sealing ring is made with an inner injection-molded core (17) made of a first material with first properties and an outer layer (18) made of a second material with in part second properties and injection-molded together with the core. This material is fused together with the material in the core in the boundary zone. The sealing surface is at least partly formed by a part of the outer layer (18), which has lower friction on contact with a component part bearing against it than the material in the core (17).

Abstract: A combined steel oil control ring is provided that has steel side rails 1 and a steel spacer expander 2, 2a. The spacer expander includes ear portions 3, 3a for contacting the side rails. The ear portions are substantially equally spaced with each other along the internal circumferential portion of the spacer expander. The ear portions have a radially external circumferential surface respectively. The radially external circumferential surface of the ear portions is adapted to press the side rails radially outwardly by using resilient force caused by the spacer expander. The spacer expander comprises up-and-down contours each formed circumferentially along the radially external circumferential surface, for preventing the side rails from circumferentially rotating relatively to the spacer expander.

Abstract: A non-sealing,, lubricating piston ring for lubricating the cylinder wall of a piston housing in a combustion tool is disclosed. The lubricating piston ring is made from a lubricating material such as polytetrofluroethylene (PTFE). The shape of the PTFE ring is designed to optimize the lubricity of the piston housing, while allowing enough friction for the piston to operate properly within the piston housing during reciprocating cycling movement. The PTFE ring may have radial fins extending from an outer surface thereof that are angled to promote ring rotations, such that the ring moves easily along and efficiently lubricates the inner cylinder wall of the piston housing. The PTFE ring does not form a seal between the piston and the housing. Instead, the PTFE ring is positioned above or below a sealing ring, such as a steel piston ring which forms the seal between the piston and the piston housing.

Abstract: A seal for hydraulically sealing a piston rod that travels axially into and out of a housing, preferably in a hydraulic dashpot. The seal comprises a preferably resilient-plastic sealing component (5). The sealing component is provided with one or more sharp ridges (10, 11, & 12) that rest against the piston rod, is tensioned across an elastomeric component (8), and is radially and axially secured along with the latter in a seal holder (2). The sealing component has an axial cylindrical wall (6) and a radial annular flange (7). The wall rests snug against the piston rod. The elastomeric component is annular and is provided with an inner surface (9) that tapers in toward the center of the housing and that the wall rests against. The outer surface of the elastomeric component is accommodated subject to radial tension in a setback (13) in the seal holder.

Abstract: The piston ring (10) for a dry-running piston compressor consists of a first and a second ring part (10a, 10b) having gaps or butt joints (10e, 10f). These two ring parts (10a, 10b) are arranged to lie mutually concentric with respect to an axis (C). The first ring part (10a) has an essentially L-shaped cross-section, having a first arm (10h) running in the direction of the axis (C) and a second arm (10g) extending outwards in a direction essentially radial to the axis (C). The second arm (10g) has a first bearing surface (10l) and the second ring part (10b) has a second bearing area (10k). The first and the second bearing areas (10l, 10k) are designed to fit perfectly on top of each other. The first and second bearing areas (10k, 10l) exhibit a discontinuity (U1,U2).

Abstract: A piston ring for use in a cylinder of an internal combustion engine, which ring is nitride-hardened at least on the sliding surface between piston ring and cylinder wall. The nitride layer is composed of a precipitated layer and a compound layer, wherein the piston ring consists of a low-alloyed iron-base material and an oxide layer is deposited on the compound layer.

Abstract: A piston ring is broadly defined as a ring-shaped, non-stainless steel, iron alloy that is nitrided, and includes between about 1% and about 10% chromium by weight, and preferably includes between about 1% and about 2% chromium by weight, with additional alloying elements also included.

Abstract: A seal assembly for a groove or seal gland in a relatively displaceable machine part for sealing an axial machine part extending therethrough comprises a pair of annular seal elements and a support element disposed between the annular elements and radially extending wall of said groove. The annular seal elements have an axial slot therein and a key portion extending therefrom, shaped to engage the axial slot. The seal elements are arranged in an inverted nesting relationship to provide superior sealing characteristics when biased toward the machine part by said support element.

Abstract: A combined oil ring is comprised of an oil ring and an expander. The cross section of the oil ring is a generally I-shape, and the outer circumferential surfaces of outer rail portions form sliding surfaces to make contact with the cylinder wall surface. The cross section of an expander installation groove formed on the inner circumferential surface of the oil ring is formed in a rectangular shape, and an expander formed of axially corrugated ring-shaped plate material is mounted in the expander installation groove. The expander is formed by forming a rectangular cross sectional plate material in a corrugated shape in the direction of plate thickness and further forming in a ring shape. The expander installation groove of the oil ring is not limited to a rectangular shaped cross section.

Abstract: Two axially abutting individual rings (4, 5) arranged in a shared casing recess (3) at the passage (6) of a component (2) to be sealed, which each is formed of several ring segments (4′, 5′) pressed against the component (2) to be sealed by a common peripheral spring (8). The cover ring (4) facing the side (6) to be sealed is radially divided and relieved from pressure by inlet-side radial grooves (7). The actual sealing ring (5) is divided by essentially tangential sections. To reduce wear and heat transfer, the cover ring (4) exhibits a circumferential carrying shoulder (9) on the side facing the sealing ring (5), on which sits the sealing ring (5) with the circumferential peripheral surface (10) of a twist-out section (11). In addition, the pressure on the cover ring (4) is largely relieved by an inner peripheral groove (12) that is provided on the side of the carrying shoulder (9) and in contact with the delivery side (6).

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: The present invention relates to an oil sealing ring, especially that used in piston of internal combustion engine or compressor. This oil sealing ring comprises a base ring (2) with a split. An elastic ring (3) is provided in the inner circumference surface of the base ring. A radially outward annular flange (18) is provided in the outer circumference surface of the base ring. An axially upward annular projecting part (19) is provided in the area beyond the outer circumference surface of the projecting part (19). The splits of said disc ring (1) and said base ring (2) are respectively staggered from each other. This oil sealing ring can effectively prevent the leakage of the oil and the gas.

Abstract: A compression piston ring capable of reducing excessive surface pressure at a gap and adjacent portion thereto during engine operation, and capable of being produced at a low cost. The compression piston ring has generally circular shape without any notched portion. The compression piston ring has a dimensional requirements in that d1/a1 ranges from 40 to 60, and d1/h1 ranges from 30 to 55, in which d1 represents an inner diameter of the piston ring, a1 represents a radial length between inner and outer peripheral surfaces of the piston ring, and h1 represents an axial length of the outer peripheral surface. The compression piston ring is particularly available as a first compression piston ring for a supercharging type diesel engine providing high engine pressure.

Abstract: An oil control ring for a piston of an internal combustion engine has an annular body defining a central axis. The ring has a U-shaped cross-section formed of a centrally positioned web extending parallel to the axis and a pair of axially spaced rail portions integrally connected to the web. Each rail portion extends radially outwardly with respect to the web, and an extremity of each rail portion defines a land extending parallel to the axis and adapted to sealingly engage a cylinder wall. Each land defines a pair of spaced chamfered sidewalls. Each sidewall extends contiguously from each land to define a chamfered edge adjacent the land. Finally, each chamfered edge defines a concave annular sidewall. The result is a reduction of land surface area in contact with the cylinder walls of an engine to provide improved performance, particularly during the engine break-in period.

Abstract: The present invention is directed to a system for providing a fluid seal between relatively movable elements, including a hub or a drum and a piston. A groove for retaining a seal is defined in the periphery of one of the rotatable elements, and a spacer element is disposed between the seal and the groove. The seal is formed from a substantially non-deformable material, and the spacer element is substantially non-resilient. The mass of the seal and the spacer element, together with rotational forces acting on the seal and the spacer element, provide a seal between the relatively rotatable elements for preventing flow of fluid.

Abstract: Piston ring including a covering surface which covers a circumferential surface of a piston, and supporting segments having retaining surfaces which engage the upper and lower sides of the piston. The piston ring has a butt joint which enables the piston ring to be elastically deformable radially, the butt joint being designed at one end of the covering surface with at least one tongue which engages in a cutout in the other end of the covering surface. The tongue is designed with at least one retaining segment which runs in the circumferential direction and engages in a supporting manner in each case on the upper and lower side of the piston.

Abstract: A piston is disclosed having both downwardly and upwardly inclined piston ring grooves, the grooves being angled less than approximately ten degrees with respect to a horizontally extending axis. In a preferred embodiment, the grooves are less than approximately three degrees in inclination and in a most preferred embodiment, the inclination is less than approximately one degree. The grooves for the combustion seal are angled upwardly from an outer diameter of the piston to adjust for thermal drooping of the piston rings received within the grooves. The grooves for the oil-control seal are angled downwardly so that oil is scraped downwardly, but the oil control ring hydroplanes over the oil when the piston moves upwardly.

Abstract: The outer circumferential surface of a second ring is comprised of an outer circumferential surface with a taper face having an outer diameter that increases towards the downward direction, and an outer circumferential surface having the same outer diameter and extending slightly in a perpendicular direction from the lower edge of the taper-faced outer circumferential surface. An annular groove is formed near the outer circumference on a lower surface of the second ring. The annular groove is formed along the entire circumference of the ring and is open at end surfaces of the ring. The annular groove is open to a space between the third land of a piston and the inner circumferential surface of a cylinder.

Abstract: A sealing element for a dry running piston compressor, in particular for a dry running oxygen compressor, contains perfluoroalkoxy-copolymer.

Abstract: A piston and compression ring combination with a piston having a generally cylindrical configuration for mounting in a cylinder of an internal combustion engine, an annular groove adjacent the top of the piston; and a piston ring having an upper inwardly directed flange adapted to rest on top of the piston, the ring having a lower inwardly retaining foot adapted for fitting into the ring groove in the piston. Such combination for the purpose of diminishing ring crevice volume, improving performance and reducing engine emissions.

Abstract: A piston and piston ring assembly has a compression ring and a lubrication control ring. The compression ring substantially seals a combustion chamber from a crankcase chamber. The lubrication control ring is configured with a reverse-taper end surface and a wiping edge. The reverse-taper end surface allows the lubrication control ring to leave a thin lubricant coat on a cylinder wall during a piston downstroke. The wiping edge pulls lubricant upward toward the compression ring during a piston upstroke. The combination of the elements and the elements on their own result in enhanced lubrication of the compression ring and thereby increase the life of the piston ring and reduce the wear on the ring and the cylinder bore.

Abstract: A piston ring is formed over the entire surface with a gas nitrided layer. A diamond-like carbon film is formed in a thickness of 0.5 to 30 micrometers over the gas nitrided layer at the upper and lower surfaces. The diamond-like carbon film has a surface structure in which diamond-like carbon has been deposited in nodular shapes in sizes of 0.5 to 5 micrometers. The diamond-like carbon is configured with any one of an amorphous carbon structure, an amorphous carbon structure having partly a diamond structure, or an amorphous carbon structure having partly a graphite structure.

Abstract: The invention provides a piston ring and piston ring material with excellent properties since not only it has excellent properties as a piston ring, but also excellent in drawability and rolling workability in the manufacturing process of stock, very excellent bending workability can be attained even when relatively high hardness after heat treatment is established, and excellent in properties as a piston ring. The piston ring material essentially consists, by weight of 0.2 to 1.2% C, 5.0 to 25.0% Cr and the balance Fe and incidental impurities, M7C3 type carbide content existing in the structure being 4.0% or less in terms of area percent to attain excellent scuffing resistance and workability. Preferably, C is 0.2 to 0.7%, and Cr is not less than 5.0% but less than 12.0%. Cr (wt. %)/C (wt. %) is 12 to 45, preferably 15 to 45, more preferably 18 to 30. In addition, the piston ring material of the present invention may contain not more than 0.25% Si, not more than 0.30% Mn, at least one not more than 2.

Abstract: In a seal arrangement for sealing a piston rod particularly for a shock absorber of a motor vehicle, where the piston rod is supported in a cylinder so as to be axially movable therein and a slide seal ring is supported in the cylinder in engagement with the piston rod for sealing the piston rod, at least two seal elements are supported in the cylinder so as to be arranged around, and adjacent to, the slide seal ring and all are disposed in a common radial plane extending normal to the axis of the piston rod for pressing the slide seal ring into sealing engagement with the piston rod.

Abstract: According to an aspect of the present invention, a piston ring for use in internal combustion engines is provided that is made of matensite-based stainless steel material containing C of not less than 0.4 and not more than 0.8 weight percent, Si of not less than 0.16 and not more than 0.4 weight percent, Mn of not less than 0.1 and not more than 0.4 weight percent, and Cr of not less than 2.0 and not more than 11.0 weight percent, where the steel material of the piston ring has mainly chromium carbide precipitated in the base texture thereof. The steel material of the first compression ring then has a nitriding layer formed thereon. According to another aspect of the present invention, a combination of compression rings, including a first compression ring 1 and a second compression ring 2, for use in internal combustion engines, is provided. The first compression ring 1 is made of martensite-based stainless steel material containing C of not less than 0.16 and not more than 1.