Abstract: A pressure reducing valve with a valve housing, with a valve carrier in the housing interior having a throughflow channel, and with a cup-shaped valve body displaceably guided from an open position into a closed position counter to a restoring force, where the valve body abuts a valve seat on the valve carrier formed as a sealing ring, closing a channel opening. The sealing ring is held in an annular groove of the valve carrier and is axially supported by the groove flanks. The groove flank which faces the valve body ends in front of the inner circumference thereof, which abuts the sealing ring when the pressure reducing valve is closed. A sealing-lip-like circumferential molded-on formation is molded on that end face of the sealing ring which faces the valve body, and this formation moves against the inner circumference of the valve body when the primary pressure on the inlet side of the valve rises.

Abstract: A swash plate-type axial piston pump, in particular for hydraulic systems, has a cylinder drum (3) rotatable about an axis of rotation (7) in a pump housing (1) and in which pistons (9) are arranged axially movable. The actuating ends of the pistons are accessible from outside of the cylinder drum (3) and are supported at least indirectly on a swash plate (15). In order to set the stroke of the pistons (9) and the fluid system pressure generated, the swash plate can be swiveled to the desired angle of inclination relative to the axis of rotation (7) by an adjustment device (21), which has at least one swiveling lever (23) that can be deflected and returned in at least one direction by an actuator and that each has in at least one hydraulically actuated actuating cylinder (31, 43) one actuating piston (35) acting on one end on an articulation point (29) of the swivel lever (23).

Abstract: A seal ring is an annular seal ring which is configured to be interposed between first and second members, and seals a gap between the first and second members. The second member is inserted into the first member, and reciprocates in its axial direction with respect to the first member. The seal ring includes an annular base part, an annular innermost end part, and a widening protrusion part. The annular base part has a radially exterior end to contact the first member. The annular innermost end part is integrally formed with a radially interior end of the base part to contact the second member. The widening protrusion part is integrally formed with the innermost end part, and protrudes with respect to the base part in the axial direction of the second member.

Abstract: A seal ring capable of stabilizing sealing performance while reducing rotation torque. A seal ring 100 has a plurality of first dynamic pressure generation groove 131 and a plurality of second dynamic pressure generation groove 132 on an outer peripheral surface thereof with intervals in the circumferential direction, the plurality of first dynamic pressure generation groove 131 extending from a position close to a first side surface 100A with respect to the center of width in an axial direction to the first side surface 100A and configured to generate dynamic pressure with relative rotation between a housing and the seal ring 100, and the plurality of second dynamic pressure generation groove 132 extending from a position close to a second side surface 100B with respect to the center of width in the axial direction to the second side surface 100B and configured to generate dynamic pressure with the relative rotation between the housing and the seal ring 100.

Abstract: A recessed part formed on a side surface includes a dynamic pressure part extending in the circumferential direction to converge on the side surface, and an introduction part extending from the dynamic pressure to open the dynamic pressure part toward the inner periphery side. One or two inner peripheral wall parts are provided for each of the recessed parts. The inner peripheral wall part is a portion defined on the inner periphery side of the corresponding recessed part by the dynamic pressure part and the introduction part. The inner peripheral wall part includes an inner peripheral wall surface. The inner peripheral wall surface extends toward the introduction part in the circumferential direction with inclining with respect to the side surface such that the inner peripheral wall surface is depressed from the side surface.

Abstract: A piston ring which is resinous includes an annular main body portion having an inner peripheral surface and an outer peripheral surface facing each other and a pair of side surfaces interconnecting the inner peripheral surface and the outer peripheral surface and a joint portion 3 formed in the main body portion. The joint portion has a step shape when viewed from at least one of the pair of side surfaces and the outer peripheral surface. The outer peripheral surface has a tapered surface having an outer diameter increasing from a side of one side surface of the pair of side surfaces of the main body portion toward a side of the other side surface.

Abstract: The present invention relates to a two-part oil scraper ring, which comprises an L-shaped base body and an axial stabilization element. The L-shaped base body has a ring flank leg, which is pressed against a piston ring groove flank by the axial stabilization element, and a bearing surface leg, on which a scraping web is arranged. A twist compensation is attained by means of a suitable selection—and in particular variation—of hearing surface leg length, ring flank leg length and axial position of the scraping web.

Abstract: A piston ring for an internal combustion engine is provided, having at least one indentation provided on a ring edge of the piston ring, wherein the at least one indentation in the circumferential direction of the piston ring has a varying depth profile.

Abstract: A protective covering support structure for an automated machine, comprising a first ring member having a channel extending substantially along an inner circumferential periphery, and a second ring member configured to be housed within the channel of the first ring member, the second ring member having a first end and a second end, the first and second ends being separated by a gap, wherein the first ring member is configured to be fixedly secured to the automated machine through a pressure-tight engagement.

Abstract: A piston ring for an internal combustion engine or for a compressor, in particular a piston ring includes an exterior running surface (3), two flanks (5, 6), and an interior circumferential surface (7); the running surface (3) has a profiled section with a groove (2), the groove (2) being located between an upper portion (3?) of the running surface and a lower portion (3?) of the running surface in relation to the cross-section of the piston ring (1).

Abstract: A compression piston ring for an internal combustion engine, comprising a sliding surface formed by two ridges, upper and lower flank surfaces, and an inner circumferential surface, wherein the lower ridge runs at least in some regions parallel to the counter sliding surface and the upper ridge is designed as a taper faced Napier element.

Abstract: A piston bearing structure for a fluid pressure cylinder includes one seal ring which is housed in a housing groove of a piston and is held in sliding contact with a cylinder tube and two backup wear rings which is housed in a housing groove of a piston, is held in sliding contact with a cylinder tube and sandwiches the seal ring. The backup wear ring includes a pressure relief groove which faces the housing groove and extends over the backup ring portion and the wear ring portion, and the pressure relief groove allows opposite sides of the backup wear ring to communicate between the piston and the cylinder tube.

Abstract: Provided is a seal ring that has low-leakage characteristics and low-friction characteristics and can improve the drive loss of the automatic transmission of an automobile to thereby contribute to an improvement in the fuel consumption of the automobile. The seal ring is attached to a shaft groove formed on the outer peripheral surface of a shaft. A plurality of peripherally spaced recessed sections are formed on at least the inner peripheral side of a contact side-surface. Inner walls are provided on the inner peripheral side of the recessed sections, and oil introduction openings that open on an inner peripheral surface are provided on the inner peripheral side of the recessed sections. The inner walls may be provided on opposite peripheral sides of the recessed sections but may be provided only on the rear side in the rotation direction.

Abstract: An oil-reserving piston ring includes an upper wedge ring (100a,200a) and a lower wedge ring (100b,200b) jointed with each other. The upper wedge ring (100a,200a) and the lower wedge ring (100b,200b) are each arranged with an opening, the upper wedge ring (100a,200a) has a first working surface (101,201) contacting with the wall of a cylinder, the lower wedge ring (100b,200b) has a second working surface (102,202) contacting with the wall of the cylinder, and at least one of the first working surface (101,201) and the second working surface (102,202) is arranged with at least one oil-reserving groove (105,106,205,206). Also provided is a piston (600) with only one piston ring slot which is used for arranging the oil-reserving piston ring. The oil-reserving piston ring has a good lubricating property and seal, and is high in reliability.

Abstract: A high-quality internal combustion engine oil ring which stably keeps oil consumption low for a long period and in which the shapes of an upper rail and a lower rail can be formed at low cost with high accuracy. The internal combustion engine oil ring has a recessed stepped portion formed at a corner of a sliding surface of an outer peripheral sliding projection in sliding contact with a cylinder inner wall surface of at least one of a first rail and a second rail constituting an oil ring main body, in a shape in vertical cross-section along a sliding direction of the first rail and second rail, and a wall surface of the recessed stepped portion has an arcuate surface having a radius of curvature of 0.02 mm to 0.08 mm.

Abstract: An oil scraper piston ring includes a ring body having two radial outer running webs on the ring body, which are arranged one behind the other in relation to the run direction of the piston and are spaced apart from one another by an external depression. Each running web respectively has two scraper lips and a wear protection coating is provided on each scraper lip.

Abstract: A high-quality internal combustion engine oil ring which stably keeps oil consumption low for a long period and in which the shapes of an upper rail and a lower rail can be formed at low cost with high accuracy. The internal combustion engine oil ring has a recessed stepped portion formed at a corner of a sliding surface of an outer peripheral sliding projection in sliding contact with a cylinder inner wall surface of at least one of a first rail and a second rail constituting an oil ring main body, in a shape in vertical cross-section along a sliding direction of the first rail and second rail, and a wall surface of the recessed stepped portion has an arcuate surface having a radius of curvature of 0.02 mm to 0.08 mm.

Abstract: An oil-reserving piston ring includes an upper wedge ring (100a,200a) and a lower wedge ring (100b,200b) jointed with each other. The upper wedge ring (100a,200a) and the lower wedge ring (100b,200b) are each arranged with an opening, the upper wedge ring (100a,200a) has a first working surface (101,201) contacting with the wall of a cylinder, the lower wedge ring (100b,200b) has a second working surface (102,202) contacting with the wall of the cylinder, and at least one of the first working surface (101,201) and the second working surface (102,202) is arranged with at least one oil-reserving groove (105,106,205,206). Also provided is a piston (600) with only one piston ring slot which is used for arranging the oil-reserving piston ring. The oil-reserving piston ring has a good lubricating property and seal, and is high in reliability.

Abstract: There is described an oil control ring (1) idealized for internal combustion engines and formed by a ferrous body less than 2.0 millimeters high, which comprises two external contact surfaces (102) where each surface (102) contains a first (22) and a second (23) end ridges, two slanted faces (3) where each slanted face (3) contains a third end (32), a peripheral cross section (4) facing the cylinder wall (5) and an internal circular section (6) facing the side of the piston (7), where each contact surface (102) has a height (h) between the first (22) and the second (23) end ridges of up to 0.15 millimeters and the angle of the slanted face (3) is comprised between 8 and 12 degrees and also by the peripheral cross section (4) is solid, without the presence of cracks, holes and/or other kinds of oil drainage areas. The ring (1) permits an improved distribution of the contact pressure of the combination and, therefore, a better conformability of the ring with the cylinder wall.

Abstract: A piston ring for the piston of an internal combustion engine, comprising, on a lower side of the piston ring, a circular, radially inner bezel, the width thereof reducing, on both sides of the ring stop, up to the side of the piston ring that is opposite the ring stop, in a symmetrical manner in relation to a radially situated axis and runs through the ring stop, and the bezel on the lower side of the piston ring is arranged away from the piston base. A good oil-scraping effect of the piston ring is obtained over the entire periphery of the inner wall of the cylinder.

Abstract: In a piston seal element and a deceleration structure including a piston seal element which has a deformation area delimited in the longitudinal direction of the seal element by frontal face areas and a sleeve surface area with at least one channel extending between the two frontal face areas, the channel extends screw thread-like around the seal element between the frontal face areas thereof.

Abstract: One embodiment of the present subject matter includes a stack of substantially planar electrodes, the stack in alignment and having a stack form factor. Embodiments include a first housing portion including a first beveled edge at least partially defining a first stack aperture adapted to at least partially receive the stack, the first stack opening having a first thickness proximal the beveled edge, and a second thickness away from the first beveled edge and a second housing portion including a second edge defining a second stack aperture adapted to at least partially receive the stack. Embodiments are included wherein the second housing portion is joined to the first housing portion such that the first housing portion and the second housing portion define an interior space which substantially conforms to the stack form factor.

Abstract: An oil wiper ring, comprising a body with a radially external running surface, an inner circumferential surface and an upper and lower face, and which possesses at least two slide ribs, which may be provided with a wear-resistant layer, such ribs becoming conically thinner, in the radial direction of their end faces, and which are opposite a sliding mating surface, such that they proceed from the body, at a specifiable angle, in order to form an angled side face, so that the free end of each slide rib, commencing in the region at the oil chamber side, is shaped to slope towards an area at the combustion chamber side, such that the associated transitional areas, on the one hand, from the region of the circumferential slide rib towards the angled side faces, and on the other hand, from the angled side faces to the piston ring body, are rounded, i.e. have predetermined radii.

Abstract: A seal ring for sealing an annular clearance between two members, which are made rotatable relative to each other. The seal ring is provided with a relief 5 throughout the circumference of a sliding face side to confront the side wall face 72 of an annular groove 71. This relief 5 is set to have a radially smaller width in the vicinity of a separate portion 2 and a radially larger width at a position apart from the separate portion 2, and the portion of the relief 5 to transit from the narrower portion to the wider portion is set to have a gradually changing width.

Abstract: The invention relates to a piston ring (1) for the piston of an internal combustion engine, comprising a circular, radially inner bezel (2), the width thereof reducing, on both sides of the ring stop (3), up to the side (4) of the piston ring (1) that is opposite the ring stop (3), in a symmetrical manner in relation to a radially situated axis (8) and runs through the ring stop (3), and the bezel on the lower side of the piston ring (1) is arranged away from the piston base. A good oil-scraping effect of the piston ring (1) is obtained over the entire periphery of the inner wall of the cylinder.

Abstract: A seal ring for sealing an annular clearance between two members, which are made rotatable relative to each other. The seal ring is provided with a relief 5 throughout the circumference of a sliding face side to confront the side wall face 72 of an annular groove 71. This relief 5 is set to have a radially smaller width in the vicinity of a separate portion 2 and a radially larger width at a position apart from the separate portion 2, and the portion of the relief 5 to transit from the narrower portion to the wider portion is set to have a gradually changing width.

Abstract: This invention describes a piston ring consisted of a “C” shaped spiraled wire acting as an expander for a seal ring of a softer material such as Teflon or Nylon; also acting as a split sealing device between two adjacent surfaces.

Abstract: A compact simplified compressor apparatus is provided with a rotating shaft rotationally driven by a motor, a compact compressor activated by the rotating shaft, an air feeding means for feeding a high-pressure air from the compact compressor to a tire, and a power source plug supplying an electricity to the motor. The compact compressor is provided with a rod attached to the rotating shaft via a crank, a piston having a peripheral groove in an outer peripheral surface and integrally formed with the rod, a cylinder having a cylinder chamber receiving the piston so as to freely reciprocate, and a ring seal sealing between the piston and an inner peripheral surface of the cylinder chamber. The ring seal is provided with a base portion having a base surface seating on a groove wall surface in the rod side of the peripheral groove, and inner and outer lip portions, each extending from the base portion toward radially inside and outside so as to be opened toward the opposite rod side.

Abstract: A plurality of first inclined faces (51) are provided on a side face of a seal ring (5) to be distanced away from each other. The first inclined face (51) opens to an inner circumferential face (23) and the side face of the seal ring (5). A column portion (54) is provided between adjacent first inclined faces (51). Portions at both ends of the first inclined face (51) serve as converging portions (52) that are conical smoothly-inclined faces, each converging to the adjacent column portion (54). On the column portion (54), the second inclined face (57) is formed.

Abstract: Apparatus and method for providing a sealing member with enhanced hoop strength. In some embodiments, a valve assembly includes a piston and first means for establishing a fluid-tight seal when the piston is in a closed position and for preventing a blow out condition when the piston is transitioned to an open position. In other embodiments, a sealing member is characterized as an endless annular ring which extends about a central axis, the sealing member comprising an elongated circle cross-sectional shape while the sealing member is maintained in an uncompressed state. In other embodiments, a method comprises extruding a sealing material through an extrusion assembly to form an endless annular ring which extends about a central axis, the extrusion assembly imparting a desired amount of curvilinearity along a longitudinal length of the material to form an orthogonal seam when a leading and trailing edge of the material are adjoined.

Abstract: A piston ring is positioned in a groove of a piston and has an outer peripheral face. The outer peripheral face is generally tapered to an edge and includes a projection. The projection extends radially outwardly from the outer peripheral face along an upper surface of the piston ring. The projection reduces the gap between the outer peripheral face and a wall of the surrounding cylinder. The gap is typically exposed to combustion gases and the projection reduces the exposed area. Ring collapse is the separation of the outer peripheral face from the wall of the cylinder because of downward pressure forces of the combustion gases. Accordingly, the projection reduces the occurrence of ring collapse.

Abstract: In mounting a combined oil control ring in a ring groove formed in a piston, the combined oil control ring is mounted in a form that an opening between but ends of an oil ring body is widened. In such an operation, it is likely that a coil expander falls off the oil ring body thus making the mounting operation cumbersome. To overcome such a drawback, a relationship L1<L2 is established. Here L1 means a axial distance between open peripheries of the groove portion and L2 means a maximum axial distance between peripheries of the groove portion.

Abstract: The invention relates to an oil control ring for pistons of internal combustion engines. The aim of the invention is to provide an improved shape-adaptation capacity in comparison to prior art, with a tangential force that enables the ring to guarantee low friction and also low oil consumption during the operation of the engine. To achieve this, the inventive oil control ring comprises a solid bearing surface that lies against the cylinder wall, in addition to parallel ring flanks, between which a radial recess that runs around the periphery is configured in the rear of the ring, said recess being designed to receive a coil spring. The peripheral region of the ring flanks is provided with undulating end faces that face towards the rear of the ring. Said undulating end faces of the upper and lower ring flanks are offset out of phase with one another.

Abstract: In a corner portion (2) defined between an outer peripheral surface (4) and a lower-side surface (3) of a steel piston ring (1), a groove (5, 6) having either an approximately quadrangular shape with a length of one side of 0.05 to 0.4 mm or an approximately quarter circular shape having a radius of 0.05 to 0.4 mm is formed. A sharp edge (9) formed by the groove (5, 6) performs an oil scraping function and the groove (5, 6) works to reduce an oil pressure of a second land or a third land clearance between the cylinder bore and the piston.

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 valve assembly including a housing having a flow channel and an annular surface surrounding the flow channel, a slide plate movable to a closed position, and a seal ring positioned between the annular surface and the slide plate. The seal ring includes a first and second sides, a first surface extending between the first and the second sides and facing towards the annular surface of the housing, and a second surface axially spaced from the first surface and extending between the first and the second sides and facing towards the slide plate. The second surface includes a continuous annular sealing portion for contacting the slide plate when the seal ring is biased against the slide plate so that a fluid-tight seal can be formed between the continuous annular sealing portion and the slide plate, and at least one passageway positioned between the annular sealing portion and the second side.

Abstract: The invention relates to a slot piston ring (1) for the pistons of internal combustion engines or compressors, having a peripheral recess (9) (a so-called scraper ring) that extends close to the slot (2) on the external periphery (3) of the piston facing away from the combustion chamber. The aim of the invention is to reduce oil consumption and the amount of leakage gas of such a piston. To this end, the recess is configured to extend from a zone (10) diametrically opposite the slot, starting with a maximum height (12) which gradually decreases to zero (13) in the direction of the slot or close to the slot.

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 flexible, resilient incompressible seal for a butterfly valve is disclosed formed from a loop having a perimeter mounting surface and a perimeter sealing surface with first and second oppositely disposed axial surfaces extend between the perimeter sealing and mounting surfaces. Channels are positioned in the axial surfaces in spaced relation around the seal. The channels extend from the perimeter mounting surface toward the perimeter sealing surface and provide fluid communication to the perimeter mounting surface allowing fluid trapped against the perimeter mounting surface to escape when compressed by the closing of the valve. A void space is positioned in the perimeter mounting surface in the form of grooves or dimples allowing the perimeter sealing surface to deform under compression when the seal is captured within the valve and substantially restrained from deforming.

Abstract: There is provided a sealing device (10) for a unitised grease-or oil-lubricated package bearing assembly comprising a twin outer race (14) and two inner races (15, 16) arranged next to each other on a shaft (12), with their faces abutting. Typically, oil may be present between the said shaft (12) and the bore surfaces of the bearing inner races (15, 16), for the purpose of lubricating parts of the system adjacent to the bearing, but not the sealed, lubricated bearing itself. The scaling device comprises a substantially annular sealing portion (26) and the provision of a step (29) in the abutting face of one of the inner races such that a substantially rectangular-section groove (30) is created on the outside diameter of the abutting inner races (15, 16).

Abstract: The invention relates to a slot piston ring (1) for the pistons of internal combustion engines or compressors, having a peripheral recess (9) (a so-called scraper ring) that extends close to the slot (2) on the external periphery (3) of the piston facing away from the combustion chamber. The aim of the invention is to reduce oil consumption and the amount of leakage gas of such a piston. To this end, the recess is configured to extend from a zone (10) diametrically opposite the slot, starting with a maximum height (12) which gradually decreases to zero (13) in the direction of the slot or close to the slot.

Abstract: The aim of the invention is to prevent deposition of material on the piston ring flank (6) of a piston ring (3) for the piston (1) of an internal combustion engine. To this end, said piston ring is provided with channels (7) which are distributed on the circumference of said piston ring flank and which preferably are positioned radially thereon. Said channels are produced on the piston ring in a simple manner by using a laser.

Abstract: In a master/slave cylinder system for clutches or brakes, primary seals have bevels which interact with similar bevels of formations on housings of the respective cylinders. Along with the lowest possible friction in the region of the sealing lips, this permits carrying out uncomplicated pressure/negative-pressure filling in the case of the master cylinder. The primary seals slide by the wedge of effects in the direction of the pressure on the bevels of the annular formations and reduce the annular bearing face of the sealing lip in a frictionally optimized manner.

Abstract: A combustion gas seal for injectors having the function to prevent the leak of a combustion gas when the injector is mounted on a cylinder head of an engine, wherein the seal is made of a resin and the entire surface of the combustion gas side end of the seal is exposed to the pressure of the combustion gas. The seal exhibits improved sealing performance together with improved soundproofing effect.

Abstract: In a fuel injector having a plunger-and-barrel pumping assembly, a sealing member is mounted within an annulus of a plunger to prevent the dilution of pressurized fuel within the barrel of the tool. The sealing member includes a hollowed cavity which traps upward moving pressurized fuel and forces an extension or wiper of the sealing member upward and outward into sealing engagement with the inner surface or bore of the barrel.

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: In an annular groove carried by one of a pair of reciprocally movable members, a pin extending into the annular groove and a sidewall of the other one of the pair of reciprocally movable members, a seal assembly comprising a ring carried by an annular body mounted in the annular groove for sealing the reciprocally movable members for minimizing fluid leakage between the members, wherein the pin extends into and through a notch carried by the annular body and an end gap of the ring for retarding rotation of and between the annular body and the ring.

Abstract: The present invention provides a piston ring structural body composed of an outer ring continuously formed of a resinous material, an inner ring continuously formed of a resinous material and a ring tensile force applying member for pressing the outer ring radially outwards via the inner ring. The piston ring structural body has a construction wherein the outer ring continuously formed of polyimide is pressed outwards in the radial direction of the piston by a coil expander via the inner ring continuously formed of PTFE. A sliding face of the outer ring, which slides on a cylinder wall, is divided into upper and lower sliding faces, whose respective upper edge portions are provided with chamfers. A contact portion of the inner ring that contacts the coil expander is provided with an upper inclined face extending inwards and upwards and a lower inclined face extending inwards and downwards. The angles of inclination of the upper and lower inclined faces range from 30° to 60°.