Abstract: Gas admission valve assembly includes a housing, an elongated valve guide disposed within a central bore of the housing, a valve including a valve stem slidably disposed within the valve guide and a valve head selectively engagable with a valve seat of the housing to control flow between gas entry and exit openings into a housing entry chamber. First and second stem seals are disposed at opposite ends of the valve guide in sealing engagement with the valve stem between the valve stem and the central bore of the housing distally and the valve guide proximally.

Abstract: A valve stem seal includes an elastomeric annular seal body including a first seal body section and a second seal body section. The first seal body section includes a first seal lip configured to sealingly abut against the valve stem to delimit an oil space and a second seal lip axially spaced from the first seal lip and configured to sealingly abut against the valve stem to delimit an air space. The first seal body section includes an annular channel in a radially inner wall between the first seal lip and the second seal lip that is spaced from the valve stem when the valve stem seal is mounted on the valve stem, and the surface of the channel includes an undercut configured to facilitate a deformation of the second seal lip toward the first seal lip.

Abstract: Disclosed is a seal for an engine firewall. The seal including a proximal part having a recess; a distal part having a notch; and a flexible intermediate part integrally extending between the proximal part and the distal part.

Abstract: A valve stem seal exhibits superior workability of mounting of a reinforcing ring to a valve stem guide and enables the reinforcing ring to be fixed to the valve stem guide in a stable manner. A reinforcing ring is mounted to a valve stem guide by fitting a cylindrical portion to the valve stem guide from a side opposite to an inward flange portion. The cylindrical portion includes a slit extending linearly in a circumferential direction and a locking protrusion that is provided on a side opposite to the inward flange portion with respect to the slit and that is to be locked by a locking recess formed in the valve stem guide. The locking protrusion is constituted by a curved portion that is gradually recessed radially inward from the side opposite to the inward flange portion with respect to the slit to a position that reaches the slit.

Abstract: A valve stem seal assembly has a metal retainer, an elastomeric seal, and a metal valve guide. The metal retainer and the elastomeric seal are attached to each other, and the elastomeric seal is in sealable contact with the metal valve guide, while the metal retainer is in metal-to-metal gripping contact with the metal valve guide. A stop may be formed in the metal retainer that cooperates with a shoulder formed in the metal valve guide in order to prevent over-installation of the assembly of the elastomeric seal with attached metal retainer, when this assembly is installed over the metal valve guide.

Abstract: Described herein is a gasket for a valve of an internal-combustion engine; the valve comprises at guide element defining a through seat, find a stein slidably mobile in said seat; the gasket comprises an annular sealing element, which is elastically deformable and is designed to be set externally on the valve to co-operate both with the guide element and with the stem, and an annular supporting member, which is set coaxially on at least part of the sealing element in such a way that the latter is radially pressed between the supporting member and the valve; the supporting member comprises a first portion for interaction with the sealing element and a second portion for positioning in use the gasket on the engine; the first and second portions of the supporting member form part of a first component and a second component respectively, that are distinct from one another and are mounted coaxially by snap-action coupling means.

Abstract: A valve stem seal (1) seals a valve stem (4) that is reciprocally movable in an axial direction. The valve stem seal includes a base body (8) that is connectable with a valve stem guide (6). A first seal lip (10) is resiliently positioned relative to the base body via an elastic connection (16) and seals the valve stem relative to an oil chamber (24). A second seal lip (12) is spaced in the axial direction (2) from the first seal lip and seals the valve stem relative to a gas chamber. The second seal lip is also resiliently positioned relative to the base body via the elastic connection.

Abstract: An eccentricity tolerant valve stem seal assembly includes an elastomeric seal having an upper metal retainer extending down and within an upper seal portion which has an inwardly directed sealing lip for contacting a valve stem. There are also a flexible middle and a lower seal portions. The lower seal portion is connected to a lower metal seal retainer that is disposed up to a lower edge of the middle seal portion. The flexible middle seal portion allows the upper seal portion to flex from an eccentric valve stem without losing the sealing function of the sealing lip. In cooperation with the above described structure, a separate cover may be in a tight tolerance fit with the lower seal retainer over top of the eccentricity tolerant valve stem seal, in order to limit axial displacement of the upper portion of the seal due to high manifold pressure.

Abstract: A reductant delivery unit (10) includes a fluid injector (12) and a flange (20) coupled with the fluid injector. An exhaust boss (28) has a surface (39) defining a through-hole (40) that communicates with a vehicle's exhaust flow path. The flange is coupled to a mounting surface such that the outlet of the fluid injector communicates with the exhaust flow path so as to control injection of urea solution into the exhaust gas flow path. A gasket (32) is sandwiched between the flange and the mounting surface. The gasket has a surface (37) defining a through-hole (38) therein that communicates with the through-hole in the exhaust boss to permit the urea solution to pass from the fluid outlet to the exhaust flow path. Gasket shielding structure (44) covers the surface defining the through-hole in the gasket to prevent the urea solution from contacting the gasket.

Abstract: A valve stem seal assembly for an internal combustion engine includes an annular rigid case disposed around a valve guide and a valve stem. An annular elastomeric body is press fit within the annular rigid case and including a radially inwardly extending seal lip in sealing contact with the valve stem. The annular elastomeric body includes a first axial end facing the valve guide and a second axial end facing away from the valve guide. The annular rigid case includes a radially inwardly extending end wall opposing the second axial end of the annular elastomeric body and including a lip support extending axially from an inner portion of the radially inwardly extending end wall and opposing a radially inner surface of the radially inwardly extending seal lip.

Abstract: A gasket for a valve in an internal combustion engine is provided with a first elastically deformable portion adapted to cooperate with a rod of the valve. A second elastically deformable portion is adapted to cooperate with an outer surface of a guide element of the valve, and a third elastically deformable portion is interposed between the first and the second elastically deformable portions and bearing a cantilevered gas tight seal lip is adapted to cooperate with the rod of the valve. The lip displays a frustoconical configuration with a section decreasing in opposite direction to the pressure forces directed towards the first elastically deformable portion and is connected to the third elastically deformable portion at its greater section part. The lip is further connected on the side exposed to the pressure forces, to the third elastically deformable portion by a surface bearing one or more waves.

Abstract: A valve stem seal can include an elastomeric component having a first portion for having a sealed engagement with a valve stem, and a pressure relief lip engaging a valve guide. The pressure relief lip can have a sealing configuration and a venting configuration. The venting configuration can allow excess exhaust gases to vent from a combustion chamber. After the venting of excess exhaust gases, the pressure relief lip can close to the sealing configuration to prevent oil from entering the combustion chamber. The elastomeric body or the valve guide can include a pressure relief channel. The elastomeric body can also include a bumper engaging the valve guide. The pressure relief channel can be disposed in the bumper.

Abstract: A valve stem seal assembly in an internal combustion engine includes a cylinder head including an aperture therein in communication with a cylinder bore and a recessed pocket surrounding the aperture. A valve guide is received in the aperture and a valve stem is received in the valve guide. A valve seal support includes a radially outwardly extending flange disposed against a surface of the cylinder head external to the recessed pocket and a cylindrical body that extends into the recessed pocket. A valve spring contacts the flange and a resilient seal is secured to the rigid valve seal support and in sealing engagement with the valve stem.

Abstract: A valve stem seal assembly has a metal retainer, an elastomeric seal, and a metal valve guide. The metal retainer and the elastomeric seal are attached to each other, and the elastomeric seal is in sealable contact with the metal valve guide, while the metal retainer is in metal-to-metal gripping contact with the metal valve guide. A stop may be formed in the metal retainer that cooperates with a shoulder formed in the metal valve guide in order to prevent over-installation of the assembly of the elastomeric seal with attached metal retainer, when this assembly is installed over the metal valve guide.

Abstract: A stem shoulder seal with double rings is composed of a sealing ring, a clamping ring and a spherical or conical stem shoulder, and the sealing ring is of a self-energized seal designed to its ultimate allowable strength and automatically free of any load beyond its ultimate strength. An assembly of independent dual stem seals, consisting of a stem shoulder seal with double rings, a stem cylinder seal with triangular sections and an isolating mating, can ensure that a stem has three seals which get well seated automatically at the same time to bear an identical ultimate medium pressure independently or without any mutual interference in service when assembled to the extent that the stem operating torque is just definitely increased, thereby ensuring that a stem sealing has a triple safety.

Abstract: A valve stem seal (1) seals a valve stem (4) that is reciprocally movable in an axial direction. The valve stem seal includes a base body (8) that is connectable with a valve stem guide (6). A first seal lip (10) is resiliently positioned relative to the base body via an elastic connection (16) and seals the valve stem relative to an oil chamber (24). A second seal lip (12) is spaced in the axial direction (2) from the first seal lip and seals the valve stem relative to a gas chamber. The second seal lip is also resiliently positioned relative to the base body via the elastic connection.

Abstract: A valve stem seal assembly in an internal combustion engine includes a cylinder head including an aperture therein in communication with a cylinder bore and a recessed pocket surrounding the aperture. A valve guide is received in the aperture and a valve stem is received in the valve guide. A valve seal support includes a radially outwardly extending flange disposed against a surface of the cylinder head external to the recessed pocket and a cylindrical body that extends into the recessed pocket. A valve spring contacts the flange and a resilient seal is secured to the rigid valve seal support and in sealing engagement with the valve stem.

Abstract: An eccentricity tolerant valve stem seal assembly includes an elastomeric seal having an upper metal retainer extending down and within an upper seal portion which has an inwardly directed sealing lip for contacting a valve stem. There are also a flexible middle and a lower seal portions. The lower seal portion is connected to a lower metal seal retainer that is disposed up to a lower edge of the middle seal portion. The flexible middle seal portion allows the upper seal portion to flex from an eccentric valve stem without losing the sealing function of the sealing lip. In cooperation with the above described structure, a separate cover may be in a tight tolerance fit with the lower seal retainer over top of the eccentricity tolerant valve stem seal, in order to limit axial displacement of the upper portion of the seal due to high manifold pressure.

Abstract: A valve stem seal (10) for a combustion engine may comprise a cylindrical body (12) including a mounting portion (16) and a valve stem sealing portion (14) integrally formed with the mounting portion (16), and an o-ring (26) configured for sealing engagement with a valve stem reciprocating in a valve guide (40) of a valve of the combustion engine. The mounting portion (16) may define an opening (18) for receiving an upper end (43) of the valve guide (40) and may be configured for substantially fluid-tight engagement with the upper end (43) of the valve guide (40). The valve stem sealing portion (14) may include an annular groove (22) formed in an inner surface of the cylindrical body (12). The o-ring (26) may be received in the annular groove.

Abstract: A valve stem seal can include an elastomeric component having a first portion for having a sealed engagement with a valve stem, and a pressure relief lip engaging a valve guide. The pressure relief lip can have a sealing configuration and a venting configuration. The venting configuration can allow excess exhaust gases to vent from a combustion chamber. After the venting of excess exhaust gases, the pressure relief lip can close to the sealing configuration to prevent oil from entering the combustion chamber. The elastomeric body or the valve guide can include a pressure relief channel. The elastomeric body can also include a bumper engaging the valve guide. The pressure relief channel can be disposed in the bumper.

Abstract: A valve seal has a sealing lip and a compressible portion. The valve seal is utilized to seal a valve guide and a stem. The valve guide has a height within a predetermined range of heights and the sealing lip sealingly engages the stem. The compressible portion has at least two articulating portions with a hinge portion between the two articulating portions. The compressible portion sealingly engages the valve guide and articulates to accept the valve guide without substantially deforming the lip or interfering with the stem.

Abstract: A valve stem seal can include an elastomeric component having a first portion for having a sealed engagement with a valve stem, and a pressure relief lip engaging a valve guide. The pressure relief lip can have a sealing configuration and a venting configuration. The venting configuration can allow excess exhaust gases to vent from a combustion chamber. After the venting of excess exhaust gases, the pressure relief lip can close to the sealing configuration to prevent oil from entering the combustion chamber. The elastomeric body or the valve guide can include a pressure relief channel. The elastomeric body can also include a bumper engaging the valve guide. The pressure relief channel can be disposed in the bumper.

Abstract: A valve stem seal for an internal combustion engine includes a seal body having a gas seal assembly spaced from an oil seal assembly in the axial direction of the valve stem seal. The gas seal assembly includes a first gas lip and a second gas lip disposed between the oil seal assembly and the first gas lip.

Abstract: A valve stem seal can include an elastomeric component having a first portion for having a sealed engagement with a valve stem, a second portion for engaging a valve guide, and a pressure relief lip extending from the second portion. The first portion can be configured to extend away from or within the second portion, and the second portion can have a channel formed therein. The pressure relief lip can have a sealing configuration and a venting configuration. The venting configuration can allow excess exhaust gases to vent from a combustion chamber. After the venting of excess exhaust gases, the pressure relief lip can close to the sealing configuration to prevent oil from entering the combustion chamber.

Abstract: A valve stem seal assembly includes a retainer and a sealing element disposed within the retainer. The retainer includes upper and lower portions. The sealing element is attached to the upper portion of the retainer and includes a first sealing lip for sealing a valve stem. An optional second sealing lip may also be included.

Abstract: A gasket for a valve in an internal combustion engine is provided with a support element having a tubular configuration according to an axis and coaxially mounted on the valve. An elastically deformable element is interposed between the support element and the valve. The support element includes a first portion elongated according to the above mentioned axis, and a second portion extending from the first portion in a direction transversal to the axis, at least partially housed in an annular seat of the elastically deformable element and having its radially outermost end connected to the first portion itself. The support element comprises a third portion extending from the radially innermost end of the second portion and folded on the second portion itself so as to generate, in the folding area, a rounded edge cooperating with the annular seat of the elastically deformable element.

Abstract: A valve stem seal utilizes a multi-piece construction to reduce the required manufactured tolerances and/or improve the stress handling capabilities. The valve stem seal can include a first member or can which can be assembled to a second member or spring seat. The can and/or spring seat can have a plurality of axially extending resilient fingers that are biased such that when assembled the fingers are bent against the bias due to the engagement between the can and the spring seat. The fingers on the spring seat allow the spring seat to bend or move relative to the can to accommodate the loading of a valve spring on the spring seat. The use of resilient fingers on the can and/or the spring seat reduces the manufacturing tolerances required for the valve stem seal.

Abstract: A firewall sealing assembly is provided for use between a firewall and a penetrating member. The assembly comprises a flexible coupling and a secondary seal. The flexible coupling is configured to provide a primary seal between the firewall and the penetrating member. The secondary seal is configured to provide a secondary seal between the firewall and the penetrating member. The secondary seal is positioned spaced apart from the flexible coupling to define a seal cavity there between.

Abstract: A gasket for a valve in an internal combustion engine is provided with a support element having a tubular configuration according to an axis and coaxially mounted on the valve. An elastically deformable element is interposed between the support element and the valve. The support element includes a first portion elongated according to the above mentioned axis, and a second portion extending from the first portion in a direction transversal to the axis, at least partially housed in an annular seat of the elastically deformable element and having its radially outermost end connected to the first portion itself. The support element comprises a third portion extending from the radially innermost end of the second portion and folded on the second portion itself so as to generate, in the folding area, a rounded edge cooperating with the annular seat of the elastically deformable element.

Abstract: A gasket for a valve in an internal combustion engine is provided with a support element having a tubular configuration according to an axis and coaxially mounted on the valve. An elastically deformable element is interposed between the support element and the valve. The support element includes a first portion elongated according to the above mentioned axis, and a second portion extending from the first portion in a direction transversal to the axis, at least partially housed in an annular seat of the elastically deformable element and having its radially outermost end connected to the first portion itself. The support element comprises a third portion extending from the radially innermost end of the second portion and folded on the second portion itself so as to generate, in the folding area, a rounded edge cooperating with the annular seat of the elastically deformable element.

Abstract: To provide a sealing device in which a spring retainer portion integrally provided on a metal ring is neither worn away nor damaged, whereby it is made possible to achieve an easy production and a cost reduction, a sealing device is constructed by a cylindrical metal ring, a seal lip provided on one end of the metal ring and made of a rubber-like elastic material, a spring retainer portion provided on the other end of the metal ring, and a spring seated on the spring retainer portion, and the spring retainer portion is provided with an engaging means for preventing a rotating motion of the spring.

Abstract: A valve stem seal can include an elastomeric component having a first portion for having a sealed engagement with a valve stem, a second portion for engaging a valve guide, and a pressure relief lip extending from the second portion. The first portion can be configured to extend away from or within the second portion, and the second portion can have a channel formed therein. The pressure relief lip can have a sealing configuration and a venting configuration. The venting configuration can allow excess exhaust gases to vent from a combustion chamber. After the venting of excess exhaust gases, the pressure relief lip can close to the sealing configuration to prevent oil from entering the combustion chamber.

Abstract: A valve stem seal having an annular valve body with an upper surface, a lower surface, and defining an aperture is disclosed. The valve body is positioned for selective sealing engagement with a valve stem. At least one orifice is disposed on an inner surface of the annular valve body between the annular valve body and the valve stem. The orifice controls the rate of oil flow between the annular valve body and the valve stem.

Abstract: A gasket for a valve in an internal combustion engine is provided with a first elastically deformable portion adapted to cooperate with a rod of the valve. A second elastically deformable portion is adapted to cooperate with an outer surface of a guide element of the valve, and a third elastically deformable portion is interposed between the first and the second elastically deformable portions and bearing a cantilevered gas tight seal lip is adapted to cooperate with the rod of the valve. The lip displays a frustoconical configuration with a section decreasing in opposite direction to the pressure forces directed towards the first elastically deformable portion and is connected to the third elastically deformable portion at its greater section part. The lip is further connected on the side exposed to the pressure forces, to the third elastically deformable portion by a surface bearing one or more waves.

Abstract: A compressed gas cylinder valve seal comprising a non-metallic seal substrate having a top surface, and a bottom surface connected to one another along a circumferential skirt, an elastomeric material overmold retention channel passing completely through the seal substrate, an elastomeric material overmolded onto the top surface and the bottom surface and filling the elastomeric material overmold retention channel, and a gas passageway passing axially, completely through the non-metallic seal substrate.

Abstract: A valve stem seal assembly includes a changeable cap. The cap is made of a flexible material, such as plastic or the like. A sealing element with sealing lips for sealing the valve stem is integrally bonded to the cap. The cap includes one or more tabs with a gripping member that cooperates with a corresponding gripping member on the retainer to snap-fit the cap onto the retainer. The retainer can also be made of plastic material. Once fitted onto the retainer, the cap can be easily removed by constructively destroying the one or more tabs using a tool, such as a screwdriver. A cap with a new sealing element can then be snap-fit on the retainer. The changeable cap allows for replacement of the sealing element without replacing the retainer or other components of the valve stem seal assembly.

Abstract: An improved seal arrangement in an assembly such as a valve assembly in which a compression member is provided to press a seal between the compression member and the valve body. In a preferred form, the compression member includes a recess which receives a first portion of the seal, and a second portion of the seal is disposed between the compression member and the valve body. In addition, a first inclined surface is provided in the recess of the compression member. The first inclined surface contacts a second inclined surface provided on the first portion of the seal. A third inclined surface on the compression member contacts a fourth inclined surface provided at a juncture between the first and second portions of the seal. Further, a fifth inclined surface is provided on the housing to contact a sixth inclined surface provided on the second portion of the seal.

Abstract: A valve shaft seal includes a reinforcing ring having a cylindrical section extending over a certain axial length and possessing an outer diameter, a sealing element disposed on the reinforcing ring, and a valve spring supported on a radially extending end section of the reinforcing ring. To support the valve spring on the radially extending end section of the reinforcing ring, the radially extending end section extends radially farther inward in the direction of the axis of the valve shaft seal than the outer diameter of the cylindrical section of the reinforcing ring.

Abstract: A radially compliant valve stem seal assembly is adapted for installation over a valve guide of an internal combustion engine. The assembly includes a metallic cylindrical straight-walled retainer with an elastomeric sealing element chemically bonded to the interior surface of the retainer. The sealing element includes upper and lower portions; the upper portion includes a pair of sealing lips comprising an oil sealing lip and a gas sealing lip. The lips are adapted to meter oil through an interface between the seal assembly and the associated valve stem for assuring proper lubrication at the interface. The lower portion of the elastomeric sealing element provides one or more annular radially inwardly oriented gripping ribs adapted to engage the guide via an interference fit. The gripping ribs are adapted to balance forces of installation against those of securement of the valve stem seal assembly over a wide valve guide diameter tolerance range.

Abstract: A valve stem seal assembly includes a retainer with one or more built-in sprues, a cavity at one end, an annular flange on the opposite end, and a cylindrical interior passageway therebetween. The built-in sprues extend from the bottom surface of the cavity to the annular flange. When the valve stem seal assembly is fitted atop the valve guide, a gap is formed between the bottom surface of the cavity of the retainer and the top surface of the valve guide to accommodate manufacturing tolerances in the height of the valve guide. A jacket is integrally bonded to the retainer by introducing material into the cavity, through the built-in sprues, and out of the bottom of the annular flange. A method of manufacturing the valve stem seal assembly with one or more built-in sprues is disclosed.

Abstract: A valve stem seal assembly incorporates a cylindrical retainer having an axis and an upper end about which symmetrically and circumferentially arranged, alternating first and second sets of fingers have radially inwardly depending upper ends. The first set of fingers is generally parallel to the axis and the upper ends are generally perpendicular to the axis to engage a first exterior annular groove of an elastomeric seal body. The first set of fingers provides for axial attachment of the seal body to a top of a valve guide. The second set of fingers is generally arcuate and the upper ends extend radially inwardly to engage a second exterior annular groove of the seal body. The second set of fingers eliminates the need for a garter spring used by traditional valve stem seal assemblies by generating a force to urge the sealing lip against a reciprocating valve stem.

Abstract: A valve stem seal assembly incorporates a cylindrical retainer having an axis and an upper end about which symmetrically and circumferentially arranged, alternating first and second sets of fingers have radially inwardly depending upper ends. The first set of fingers is generally parallel to the axis and the upper ends are generally perpendicular to the axis to engage a first exterior annular groove of an elastomeric seal body. The first set of fingers provides for axial attachment of the seal body to a top of a valve guide. The second set of fingers is generally arcuate and the upper ends extend radially inwardly to engage a second exterior annular groove of the seal body. The second set of fingers eliminates the need for a garter spring used by traditional valve stem seal assemblies by generating a force to urge the sealing lip against a reciprocating valve stem.

Abstract: A valve stem seal assembly for an internal combustion engine includes an elastomer seal body and a metal retainer adapted to secure the seal body in place over a valve guide. The cylindrical seal body has an aperture with at least one radially inwardly directed sealing lip adapted to engage a reciprocally movable valve stem to minimize escape of oil lubricant from the engine along a path between the valve guide and stem. The retainer, formed of a spring metal cylindrical body adapted to frictionally retain the seal body at its upper end, contains first and second sets of axially depending resilient fingers at its lower end. The first set of fingers mechanically engages and supports a unique valve guide member within a valve guide aperture of a cylinder head deck, while the second set of fingers supports the seal assembly directly against the head deck under a valve spring.

Abstract: An elastomeric valve stem seal component is adapted for installation over a valve guide of an internal combustion engine. The seal component incorporates fabric reinforcement within an annular jacket body of the component. In one preferred form, the fabric is positioned intermediate two elastomeric layers of the seal body; i.e. between an inner layer and an outer layer. One preferred manufacturing method provides extrusion of a tube having a fabric reinforcement layer already provided between inner and outer layers. A cutting die incorporates a push ring adapted to move the component along a staged molding assembly process. A series of threaded core pins are utilized for conveyance of the component in the fabrication process, which includes extruding a rubber tube and cover over a series of threaded core pins, cutting a portion of the rubber tube to a predetermined length, and molding the predetermined length to produce the component.

Abstract: A valve stem seal assembly for an internal combustion engine includes an elastomer seal body and a metal retainer adapted to hold the seal body in place over a valve guide. The circumferential seal body includes an aperture containing at least one radially inwardly directed sealing lip adapted to engage an engine valve stem to minimize escape of oil lubricant from the engine, particularly along a path between the valve guide and the reciprocally moving valve stem. The seal body contains an annular exterior groove adapted to receive an end wall in the upper extremity of the retainer. The retainer, formed of spring metal, comprises a cylindrical body containing a plurality of axially depending resilient fingers. The bottom extremities of the fingers have inwardly turned ends adapted to mechanically engage a circumferentially disposed groove or a step of a boss formed in the exterior cylindrical surface of the valve guide.

Abstract: A radially compliant valve stem seal assembly for an internal combustion engine includes a metallic retainer having a plurality of circumferentially spaced, axially depending legs. Each of the legs includes at least one radially inwardly depending protuberance adapted to engage a valve guide surface. The legs are arranged and disposed on the retainer to be radially flexible, yet axially stiff, to balance forces of installation against those of securement of valve stem seal assembly over a wide valve guide diameter tolerance range. In one disclosed embodiment, the retainer has three separate circumferentially spaced legs, each including a single dimple in its structure. The dimples are adapted to provide the only direct contact of the legs with the valve guide circumference. The retainer legs are adapted to flex radially outwardly, and produce a spring tension between the dimples and the guide for maintaining the dimples in engagement with the valve guide.

Abstract: A unitized seal for use in a gas spring seal assembly. The unitized seal includes a rigid thermoplastic insert having an elastomeric sealing layer surrounding the insert and bonded to the insert. The insert provides rigidity to the seal and includes a central, axial opening that receives and guides a rod slidably engaged with the insert. The sealing layer engages the interior surface of the gas spring cylinder to prevent the pressurized gas contained within the gas spring from escaping around the seal. The sealing layer also includes a central, axial opening aligned with the passage in the insert that slidably engages the rod and further prevent gas from escaping the gas spring cylinder. The unitized seal may be formed in a single or two-step process. In the single step process, the insert and sealing layer are formed by injection molding processes in a single mold and are bonded to one another by a subsequent covulcanization process.

Abstract: An elastomeric valve stem seal component is adapted for installation over a valve guide of an internal combustion engine. The seal component incorporates fabric reinforcement within an annular jacket body of the component. In one preferred form, the fabric is positioned intermediate two elastomeric layers of the seal body; i.e. between an inner layer and an outer layer. One preferred manufacturing method provides extrusion of a tube having a fabric reinforcement layer already provided between inner and outer layers. A cutting die incorporates a push ring adapted to move the component along a staged molding assembly process. A series of threaded core pins are utilized for conveyance of the component in the fabrication process, which includes extruding a rubber tube and cover over a series of threaded core pins, cutting a portion of the rubber tube to a predetermined length, and molding the predetermined length to produce the component.

Abstract: A valve stem seal component overcomes potential orientation misplacement, particularly in cases where no valve stem seal is to be used on an adjacent valve. The component includes an integral locator feature for assuring proper installation atop a valve guide of an internal combustion engine. A plurality of such seal components are employed per engine, each component designed for insertion over at least the intake valve guide of each cylinder. Each component includes a valve stem seal module adapted to be installed over the intake valve guide. A locator is attached to the module via a radial connection portion that extends between the module and locator. The radial connection portion includes an arcuate edge that fits in only one orientation against a curvilinear edge of a boss on the cylinder head. In one described embodiment, the locator is a circular ring adapted to be installed over an exhaust guide.

Abstract: A valve stem seal assembly for an internal combustion engine includes an elastomer seal body and a metal retainer adapted to hold the seal body in place over a valve guide. The circumferential seal body includes an aperture containing at least one radially inwardly directed sealing lip adapted to engage an engine valve stem to minimize escape of oil lubricant from the engine, particularly along a path between the valve guide and the reciprocally moving valve stem. The seal body contains an annular exterior groove adapted to receive an end wall in the upper extremity of the retainer. The retainer, formed of spring metal, comprises a cylindrical body containing a plurality of axially depending resilient fingers. The bottom extremities of the fingers have inwardly turned ends adapted to mechanically engage a circumferentially disposed groove or a step of a boss formed in the exterior cylindrical surface of the valve guide.