The present invention relates broadly to a sealing construction for providing a fluid seal intermediate a pair of opposed, mating parts or structures, and more particularly to a metal retainer therefor having seal receiving grooves adapted to be fabricated by coining or a like sheet metal stamping or forming process.
In basic construction, gaskets of the type herein involved are formed of one or more resilient sealing elements which are supported by sheet metal plate or other retainer which may be machined, stamped, molded or otherwise formed to conform to the geometry of the mating surfaces to be sealed. Particularly, the seal members may be molded-in-place or otherwise mounted in grooves formed into one or both sides of the retainer. Representative such gaskets are shown, for example, in U.S. Pat. Nos. 3,195,906; 3,215,442; 3,259,404; 3,578,346; 3,635,480; 3,720,420; 3,746,348; 4,026,565, 4,625,978, 5,890,719; 6,460,859; 6,553,664; 6,669,205 and 6,761,360 and in U.S. Pat. Appln. Pub. No. 2003/0025328A1; and US2002/0030326A1, and are marketed commercially by the Composite Sealing Systems Division of Parker-Hannifin Corporation, San Diego, Calif, under the tradenames “Gask-O-Seal.”
Retainer gaskets of the type herein involved are employed in a variety of sealing applications, such as in commercial, industrial, or military equipment, vehicles, or aircraft for compression between the opposing or faying surfaces of a pair of mating parts or structures to provide a fluid-tight interface sealing thereof. In service, the gasket is clamped between the mating surfaces to effect the compression and deformation of the seal member and to develop a fluid-tight interface with each of those surfaces. The compressive force may be developed using a circumferentially spaced-apart arrangement of bolts or other fastening members, or by a threaded engagement of the mating parts.
Heretofore, the retainer grooves, which may be single or double-sided or walled, have been formed by machining. As a relatively labor-intensive and slow process, machining thus constitutes a significant expense in the overall cost of the gasket. It is believed, therefore, that lower cost alternatives would be well-received by industry, and particularly for automotive and other high volume applications.
The present invention is directed to a retainer gasket construction particularly adapted for high volume applications having complex sealing geometries. The gasket includes a retainer which may be formed of sheet metal or other metal plate, and one or more integral sealing elements supported on the retainer. The retainer is provided in accordance with the precepts of the present invention as having grooves for receiving the seal elements, which grooves are coined or otherwise stamped or sheet-metal formed into the retainer. With the grooves so formed, each of the seal elements may be molded-in-place or otherwise received into a corresponding one of the grooves. The coining of the grooves into the retainer facilitates its construction for automotive and other high volume applications. Such coining, moreover, allows structures, such as pins and slots, to be formed in the retainer in an economical manner.
The present invention, accordingly, comprises the article and method possessing the construction, combination of elements, and arrangement of parts and steps which are exemplified in the detailed disclosure to follow. Advantages of the present invention include a gasket construction which may be adapted for use with various sealing configurations, and particularly multi-port or other complex arrangements. Further advantages include a gasket construction which is economical to manufacture in high volumes. These and other advantages will be readily apparent to those skilled in the art based upon the disclosure contained herein.
For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings wherein:
The drawings will be described further in connection with the following Detailed Description of the Invention.
Certain terminology may be employed in the following description for convenience rather than for any limiting purpose. For example, the terms “forward” and “rearward,” “front” and “rear,” “right” and “left,” “upper” and “lower,” “top” and “bottom,” and “right” and “left” designate directions in the drawings to which reference is made, with the terms “inward,” “inner,” “interior,” “inside,” or “inboard” and “outward,” “outer,” “exterior,” “outside,” or “outboard” referring, respectively, to directions toward and away from the center of the referenced element, the terms “radial” or “vertical” and “axial” or “horizontal” referring, respectively, to directions, axes, or planes perpendicular and parallel to the longitudinal central axis of the referenced element. Terminology of similar import other than the words specifically mentioned above likewise is to be considered as being used for purposes of convenience rather than in any limiting sense.
In the figures, elements having an alphanumeric designation may be referenced herein collectively or in the alternative, as will be apparent from context, by the numeric portion of the designation only. Further, the constituent parts of various elements in the figures may be designated with separate reference numerals which shall be understood to refer to that constituent part of the element and not the element as a whole. General references, along with references to spaces, surfaces, dimensions, and extents, may be designated with arrows or underscores.
For the illustrative purposes of the discourse to follow, the precepts of the retainer gasket construction of the present invention are described in connection with the configuration thereof for use as an intake manifold, head gasket, or other multi-port seal within an engine for a motor vehicle. In view of the discourse to follow, however, it will be appreciated that aspects of the present invention may find utility in other fluid sealing applications requiring a flexible gasket of the type herein involved. Use within those such other applications therefore should be considered to be expressly within the scope of the present invention.
Referring then to the figures wherein corresponding reference characters are used to designate corresponding elements throughout the several views with equivalent elements being referenced with prime or sequential alphanumeric designations, shown generally at 12 in the plan view of
Retainer gaskets of type herein involved are conventionally provided as having one or more openings formed through the radial surfaces thereof, such as for a registration with cylinder bores, bolt holes, coolant or lubrication ports, and other throughbores, passageways, and chambers. In this regard, retainer 12 includes one or more openings, one of which is referenced at 20, formed through the surfaces 18. Each of such openings 20 may be configured for registration with a corresponding bore, passageway, or chamber of the engine. In this regard, it will be appreciated that the arrangement of the openings 20 shown in
Retainer 12 further has a thickness dimension, referenced at t in the cross-sectional view of
As is shown in
With continuing reference to
Additional features and structures also may be formed within the retainer 12 as the particular application may require. As is shown, for example, at 60 in
In accordance with the present invention, one or more, or all of the grooves 30a-b and 32a-b may be formed by coining or a like sheet metal stamping or forming process. With reference now to
A punch, represented at 78 in
As may be seen with reference now to
Looking next to
In the closed orientation shown in
In the commercial manufacture of the retainer 12, such retainer may be fabricated in a multi-station, progressive die operation or, alternatively, using separate dies in a transfer press operation. In such operation, the retainer 12 first may be provided as a piece of generally flat metal plate or sheet stock which, in the various die stations or dies, may be stamped, bent, and coined to form the final configuration of the retainer 12.
Turning now to
In the illustrated configuration of
In this regard, depending upon the location of such interface surface relative to the gasket 10, each of the bead portions 60 may be spaced-apart from a corresponding sidewall 34a-b, 40a-b, or 41a-b, or, alternatively and such as is shown in
Within pair of corresponding grooves 30 or 32, each of the bead portions 96 present oppositely disposed, generally hemispherical bearing surfaces which in the illustrated embodiment define radial seals on one or both sides 18 for the gasket 90. As may be seen in
For the axial compression of the seal elements 92 and 94 by the interface surfaces effecting a fluid-tight seal therewith, the bead portions 96 thereof may be provided, again as depending upon the geometry of the interface surfaces, to extend axially beyond the corresponding radial surface 18 of retainer 12 for abutting contact with a corresponding one of the interface surfaces. That is, bead portions 60 may be provided, as is shown in
With retainer 12 being provided as has been described, each of the seal elements 92 and 94 may be adhesively bonded, interference fit or, preferably, molded, or otherwise within a corresponding one of the grooves 30 or 32 as continuous or discontinuous, i.e., segmented, ring or length of an elastomeric material. For the attachment of the seal elements 92 and 94 within the grooves 30 and 32, the groove wall surfaces may be primed with a siloxane, silane, or other bonding agent. The primed retainer 12 then may be placed into a heated molded cavity for the injection, compression, or transfer molding of an uncured rubber or other elastomeric compound forming the integral seal elements. Each of the seal elements thereby may be formed and cured-in-place as vulcanized directly onto retainer 12. Alternatively, the elastomeric elements may be molded in a separate operation and otherwise bonded using an adhesive or interference fit into a groove 30 or 32.
The seal elements 92 and 94 also may be mechanically locked onto the retainer 12, such as by virtue of the elastomeric material being injected or otherwise being flowed through the slot 54 to integrally join the element 94a to the element 94b in the manner shown in
Seal elements 92 and 94 may be formed of a synthetic rubber which specifically may be selected for high temperature performance or otherwise for compatibility with the fluid being handled. Suitable materials include natural rubbers such as Hevea, as well as thermoplastic, i.e., melt-processible, or thermosetting, i.e., vulcanizable, synthetic rubbers such as fluoropolymers, chlorosulfonate, polybutadiene, polybutadiene, buna-N, butyl, neoprene, nitrile, polyisoprene, silicone, fluorosilicone, copolymer rubbers such as ethylene-propylene (EPR), ethylene-propylene-diene monomer (EPDM), nitrile-butadiene (NBR) and styrene-butadiene (SBR), or blends such as ethylene or propylene-EPDM, EPR, or NBR. The term “synthetic rubbers” also should be understood to encompass materials which alternatively may be classified broadly as thermoplastic or thermosetting elastomers such as polyurethanes, silicones, fluorosilicones, styrene-isoprene-styrene (SIS), and styrene-butadiene-styrene (SBS), as well as other polymers which exhibit rubber-like properties such as plasticized nylons, polyesters, ethylene vinyl acetates, and polyvinyl chlorides. As used herein, the term “elastomeric” is ascribed its conventional meaning of exhibiting rubber-like properties of compliancy, resiliency or compression deflection, low compression set, flexibility, and an ability to recover after deformation, i.e., stress relaxation.
Advantageously, seal elements 92 and 94 exhibit a reduced yield stress as compared to retainer 12 and, accordingly, are deformable for conforming to irregularities existing between the interface surfaces within the intended application. Further in this regard, as given compressive load is applied to the seal elements 92 and 94, an increased bearing stress is provided thereon by virtue of the reduced surface area contact of the bearing surfaces of the bead portions 96 on the interface surfaces. This increased stress generally will be sufficient to exceed the reduced yield stress of the seal elements 92 and 94 for the deformation thereof effecting the fluid-tight sealing of the interfacing surfaces. Indeed, the seal elements may be used to effect a hermetic seal which is especially useful in petrochemical and other applications to control the fugitive emission of VOC's and other pollutants.
In service, it will be observed that the combination of a relatively incompressible retainer 12 and the relatively compressible seal elements 92 and 94 provides a gasket construction which minimizes torque loss and thereby obviates much of the need for the periodic re-torquing of the members being joined. That is, it is well-known that gaskets of the type herein involved may develop a compression set which is manifested by fluid leaks as the tension in the joint is relaxed and the fluid-tight sealing of the interfacing surfaces is compromised. In this regard, the provision of bead portions 96 better ensures positive sealing, with retainer 12, in turn, synergistically providing generally a compression stop and non-yielding contact in establishing an alternative load torque path minimizing the compression set and leak potential of the gasket 90. Thus, the use of a retainer allows the mating parts to bear stress loads which otherwise would cause the deformation or extrusion of a gasket which lacked a retainer. In the case of a metal retainer 12, such contact additionally affords improved heat transfer between the interface surfaces, and also develops relatively high seal stresses for assured fluid-tight sealing of the interfacing structures.
Additional features and structures such as the pins 62 also may be formed by overmolding of the same or different elastomeric or other polymeric material as the seal elements 92 and 94. As may be seen in
Thus, a unique gasket construction for automotive and other commercial, industrial, or military applications is described which is economical to manufacture even in complex shapes, and which exhibits reliable sealing properties.
As it is anticipated that certain changes may be made in the present invention without departing from the precepts herein involved, it is intended that all matter contained in the foregoing description shall be interpreted in as illustrative rather than in a limiting sense. All references including any priority documents cited herein are expressly incorporated by reference.
The present application claims the benefit of the filing date of U.S. Provisional Application Ser. No. 60/497,777; filed Aug. 26, 2003, the disclosure of which is expressly incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 60497777 | Aug 2003 | US |