Abstract:
A system and method for supporting a valve stem of a poppet valve that is held in a normally closed position by a valve spring, the poppet valve being adapted for use in an internal combustion engine. The system includes a valve guide insert with a body having a first end, a second end, an aperture extending between the first end and the second end, an external surface having a protrusion near the second end. The first end of the guide will preferably include a threaded portion which will cooperate with a nut to provide tension to the valve guide insert. The system also includes a spring seat that includes a thermal barrier adapted for mounting about the stem and for accepting the valve spring, so that the spring may be placed over the thermal barrier and connected to the stem, allowing the stem to be supported by the spring and the valve guide insert.
Abstract:
A rocker cover gasket assembly is provided that is suitable for use in connection with a valve assembly for an internal combustion engine. The rocker cover gasket assembly includes a carrier, a plurality of valve stem seals integral with the carrier and at least one connector, wherein the connector is connected to two adjacent valve stem seals to form a linkage or a web of valve steam seals. The connectors and carrier may contain one or more handle members to improve manual or mechanical handling of the assembly. The connectors and portions of the carrier may be formed with thinned portions to allow for selective removal of individual valve stem seals in the event of wear or failure.
Abstract:
A valve stem seal assembly includes a resilient seal member mounted to a shell body having a downwardly extending skirt. At least one alignment pad or tang is provided in the skirt of the shell body for improved gripping of an outside diameter of a valve guide. In one embodiment, the alignment pad includes an inwardly projecting ramp portion connected to a generally longitudinally extending land portion and terminates in an inwardly projecting tang adjacent the land portion. In another embodiment, a valve stem seal assembly includes at least one tang having a generally arcuate end portion with a pair of spaced apart upwardly extending shoulders for gripping a valve guide.
Abstract:
A seal for being mounted on a reciprocating machine part to seal the machine part includes a sealing element made of elastomer material. The sealing element has a sealing lip defined by two surfaces that intersect at a sealing edge for resting in a sealing manner against the outer surface of the machine part. One of the two surfaces includes a first section and a second section. The first section is inclined at a first angle of inclination with respect to the central axis of the sealing element while the second section is inclined at a second angle of inclination with respect to the central axis of the sealing element, and with the first and second angles of inclination being different from one another.
Abstract:
A valve spring seat is disclosed having at least one annular flange in facing relationship with a surface of an engine head. The flange may be part of a valve seal retainer. A radial cut extending inwardly from the radially outermost edge of the flange to an intermediate position on the flange forms two opposing free edges. The first edge is bent in a first longitudinal direction to form a first tab, and the second edge is bent in a second, opposite longitudinal direction to form a second tab. The first tab engages at least one coil of the valve spring, and the second tab engages the cylinder head to prevent rotation of the spring during reciprocation of the spring.
Abstract:
A self-lubricating and wear resistant valve/valve guide combination for an engine includes a self-lubricating coating deposited on one of (a) the inner surface of the valve guide, or (b) the outer surface of the valve stem. A wear-resistant coating deposited on one of (a) the outer surface of the valve stem when the self-lubricating coating is deposited on the inner surface of the valve guide, or (b) the inner surface of the valve guide when the self-lubricating coating is deposited on the outer surface of the valve stem. The self-lubricating coating has a composition, by weight, consisting essentially of, (a) a first component, comprising, a metal-bonded chromium carbide in the range of about 60% to about 80%, (b) a second component, comprising, a soft noble metal in the range of about 1% to about 20%, and (c) a third component, comprising, a metal fluoride eutectic in the range of about 5 to about 20%. The wear-resistant coating has a composition, by weight, consisting essentially of, (a) chromium in the range of about 20% to about 30%, (b) nickel in the range of about 5% to about 15%, (c) tungsten in the range of about 1% to about 10%, and (d) cobalt in the range of about 50% to about 74%.
Abstract:
An inventive valve stem seal assembly includes a seal body bonded to a metal retainer without the need for a separate retaining ring or a garter spring. Compressive radial force between the seal body and a corresponding engagement surface of a valve stem is provided by an end wall of the retainer, and in particular, tangs which extend generally longitudinally away from the end wall. The seal body envelops the tangs, and the tangs selectively flex when a valve stem is inserted through an aperture of the seal body.
Abstract:
A valve guide (14) for guiding a stem (13) of a headed poppet valve (11) for slidable movement in an internal combustion engine has an inner bearing surface (17) of generally cylindrical shape but a groove (18) which is cut spirally into that surface extends radially outwardly therefrom and provides a lubricant passage which extends for at least part o the length of the bearing surface (17). The cross-sectional shape of the spiral groove (18) is characterized by a lower groove portion (21) which is substantially at right angles to the stem (13) and functions to scrape lubricant off the stem (13) and as he stem (13) moves downwardly in the valve opening direction, but the upper surface portion (22) of the groove (18) back into clearance space between the valve stem (13) and guide (14).
Abstract:
A valve stem sealing system for an internal combustion engine has a valve guide and an elastomeric valve seal disposed therein. The valve guide is substantially cylindrical in shape and has a longitudinal axis and first and second ends. The valve guide also has a thermal insulating element defining the second end and an internal circumferential groove proximate to the second end. The elastomeric valve seal is disposed in the circumferential groove.
Abstract:
A pre-assembled unit 10 for use in assembly of an engine valve system 150 in an engine 152. The pre-assembled unit 10 includes a spring 14 for providing a force for urging an engine valve 156 in a first direction, a spring seat 20 engaged with the spring 14, a spring retainer 78 for maintaining the spring 14 in a concentric position around the valve 156, and locks 82 for lockingly engaging the spring retainer 78 and the valve 156. The spring retainer 78 and the locks 82 transmit the spring force to the valve 156. The pre-assembled unit 10 includes a retention member 120 for temporarily maintaining the spring 14, the spring seat 20 and the spring retainer 78 together prior to installation into the engine valve system 150. The retention member 120 cooperates at its upper section 130 with the locks 82 and at its lower section 124 with an oil seal 22 on the spring seat 20 to hold the spring retainer 78 and the spring seat 20 in engagement with the spring 14. The retention member 120 is removable from the pre-assembled unit 10 upon relative movement of the valve 152 and the pre-assembled unit 10 during assembly of the engine valve system 150 in the engine 152.