Abstract: A bidirectional hydrodynamic shaft seal includes an annular plastic disk having a sealing surface or lip provided with two connected spiral grooves extending around the disk axis. One of the spiral grooves spirals outwardly in a clockwise direction, and the other spiral groove spirals outwardly in a counterclockwise direction so that the spiral grooves have multiple intersection points. The shaft seal is designed for operation in either or both directions of shaft rotation.
Abstract: A shaft seal includes an annular rigid seal case insertable into a cylindrical bore in a seal housing. The joint between the seal case and the bore is sealed by an annular resilient sleeve stretched over the outer surface of the case. The sleeve is initially formed as a thin flat annular elastomeric disk by a low cost molding or slicing operation. Installation of the sealing element on the seal case is accomplished by stretching the disk radially and then turning it angularly from a radial disk orientation to an axial sleeve configuration.
Abstract: A dual lip shaft seal includes two sealing disks bonded directly to a radial wall of an annular metal case. The radial wall has an annular step, such that two separate mounting surfaces are formed for mounting the two disks. Each sealing disk is preferably formed of PTFE and heat-bonded to its respective mounting surface by an induction heater coil disposed in confronting relation to the radial wall of the metal case.
Abstract: A unitized radial lip seal assembly includes an outer annular case and an inner annular wear sleeve loosely interlocked by flanges or walls formed at the axial ends of the wear sleeve. After initial installation of the unitized assembly within a housing, the wear sleeve can be axially shifted a slight distance to provide a slight axial separation of the wear sleeve from the annular case. Two separate lip seal elements are mounted to the outer annular case and protected from damage during shipping and installation by abutting surfaces of the case and wear sleeve.
Abstract: Polytetrafluoroethylene (PTFE) is bonded to a metal substrate such as an oil seal casing via an intermediary bonding layer of fluorinated ethylene propylene (FEP). Induction heating is used to rapidly melt the FEP and PTFE without degrading their physical properties. The induction heating unit is preferably controlled by a temperature signal representing the temperature of the metal substrate.
Abstract: A shaft seal having a thin radial section is adapted for mounting within a small radial annular clearance space between a housing and a shaft. An elastomeric sealing member is bonded to an axially inner portion of the seal and a polytetrafluoroethylene sealing member is clamped to an axially outer portion of the seal.
Abstract: A sealing element for use with a radial lip oil seal includes a mounting section formed of a first polymer and a sealing section formed of a second polymer. The sealing element sections are bonded together during a common sintering operation so that each polymer is sintered only once. This reduces molecular degradation of the polymers typically caused by multiple sintering operations.
Abstract: A lubricant seal assembly adapted for installation in an annular clearance space between a shaft and a surrounding housing. The assembly includes inner and outer case members that can be press fit on the shaft and housing. An annular bumper element is arranged between confronting surfaces of the case members to limit excessive telescopic motion of the members during the installation process. The bumper element is formed of a fusible material, such that during an initial break-in period frictional heat melts some of the bumper material to quickly produce a low friction seal assembly.
Abstract: A static dirt exclusion element is arranged in a unitized housing to contact a rotating exclusion element so as to provide a primary barrier to dust and airborne contaminants. A secondary barrier is provided in the housing in the form of a porous filter element formed of a foam or felted material to further exclude and entrap contaminants.
July 10, 1989
Date of Patent:
July 24, 1990
Mather Seal Company
Frederick R. Hatch, William M. Riley, Thomas M. Banks
Abstract: A dust excluder (12) for a seal assembly (10) such as utilized with a vehicle air conditioning compressor is disclosed as having an annular inner portion (36) that mounts on a rotatable compressor shaft (20) and as including an outer portion (38) that seals with an annular support (24) of the seal assembly axially outward from a shaft seal (30) in a manner that excludes dust to prevent seal abrasion without increased heating of the compressor shaft. The inner portion (36) of the dust excluder is preferably embodied by an annular body (56) having opposite axial ends (58,60) and the outer portion (38) is preferably embodied by a sealing section (62) having a disc (64) extending outwardly from the annular body (56) and by a sealing lip (66) extending outwardly from the disc for slidable engagement with the annular support (24). The sealing lip (66) is preferably inclined and has an edge junction that provides an annular line contact (68) with the annular support (24).
Abstract: A lip seal having enhanced shock loading capabilities includes a rigid case member coated with an elastomeric material. A composite annular sealing lip having a bonding portion formed of an elastomeric material and a contact portion formed of polytetrafluoroethylene is bonded to the case member such that a shock absorbing elastomer to adhesive to elastomer interface is formed between the sealing lip and the case coating.