Caterpillar Tractor Co.

Caterpillar Inc.

Towmotor Corporation

Harold L Reinsma

Albert L Woody

Roger L Boggs

Alan M Dickey

Lawrence E Fox

Kevin G Forster

Glenn R Gobble

Michael A Roussin

Eugene R Groff

Lloyd K Heinold

Reginald K Ringel

Terry D Linne

Robert D McFeeters

W Stanley Born

Ernest B Clark, Iii

A radial lip seal for sealing about a pin of a hinge joint is disclosed. Such seal includes an outer mounting ring, a rubber flex ring mounted inside the mounting ring, a tension ring mounted inside the flex ring, and an inner elastomeric seal ring mounted inside the tension ring. The seal ring has an inside diameter that is a sufficient amount smaller than the pin to cause the tension ring to be stretched by a predetermined amount when the seal is mounted about the pin. The tension ring is capable of exerting a radial force of at least 20 N/cm of circumference on the seal ring upon being stretched the predetermined amount. The unique construction of such a seal is effective in sealing out highly abrasive materials found in very severe operating applications, such as on earthmoving vehicles, and provides a seal having an extremely long service life in such applications.

Process of making radial lip seal

A radial lip seal for sealing about a pin of a hinge joint is disclosed. Such seal includes an outer mounting ring, a rubber flex ring mounted inside the mounting ring, a tension ring mounted inside the flex ring, and an inner elastomeric seal ring mounted inside the tension ring. The seal ring has an inside diameter that is a sufficient amount smaller than the pin to cause the tension ring to be stretched by a predetermined amount when the seal is mounted about the pin. The tension ring is capable of exerting a radial force of at least 20N/cm of circumference on the seal ring upon being stretched the predetermined amount. The unique construction of such a seal is effective in sealing out highly abrasive materials found in very severe operating applications, such as on earthmoving vehicles, and provides a seal having an extremely long service life in such applications.

Radial lip seal

A maintenance-free pivot joint is disclosed for mounting a first member of a loader linkage to a second member thereof. The first member is provided with a clevis having a pair of brackets. The pivot joint includes a pivot pin which is pivotally mounted within the second loader linkage member. A first end collar is fixedly secured to one end of the pivot pin of the joint and is slidably mounted to a first one of the pair of brackets. Conversely, a second end collar is slidably mounted on the other end of the pin and fixedly secured to a second of the brackets, but at a preselectable axial position relative to the second member. The positioning of the second end collar at the preselected position allows the joint to accommodate lateral misalignment between the first and second members of the linkage, while maintaining a closely spaced lateral relationship therebetween to eliminate end play and facilitate good sealability.

Pivot joint for loader linkages and the like

A dual operating mode seal assembly (10) wherein a frictional force maintains a seal ring (50) in a static sealing mode during either movements of a member (16) being sealed to eliminate frictional and abrasive wear to the seal ring (50) and member (16). A load ring (52) provides a shear force upon deflection sufficient to overcome the frictional force at a predetermined slip point to cause the seal ring (50) to enter a dynamic sealing mode in response to extended travel movements of the member (16).

Dual operating mode seal assembly

A flexible seal assembly 10 is provided for a joint 12 having a first member 15 which is both pivotable about and axially movable along an axis 20 relative to a second joint member 16. The seal assembly 10 is disposed within an annular recess 22 of the first joint member 15 and includes an annular seal 30 of a flexible, wear resistant material and a metallic load ring 31. The seal has an axially movable sealing portion 34 with an annular seal lip 38. The load spring 31 is disposed behind the sealing portion 34 for urging and maintaining the seal lip 38 in sealing engagement against a sealing surface 22 of the second joint member 16. A rigid stiffener ring 40 is molded into the sealing portion 34 of the seal 30 and is of a construction and position within the sealing portion 34 to provide the sealing portion with an intervening wall portion 41 of the resilient material of the seal 30 separating the stiffener ring 40 from direct force transmitting contact with the load spring 31 to prevent wear and fretting of the load spring.

Flexible seal assembly

Material fracturing apparatus

Constant strain boot seal

Seal assembly having a plastic annular sealing member with an integral

A seal apparatus (40) for sealing between relatively rotatable structures (12,14) is provided and has a pair of seal rings (62,64) which are engageable at axial sealing face portions (70,72). Axially facing surfaces (78,80) of the first seal ring (62) are arranged such that fluid pressure acting thereon biases it in a first direction. Axial positioning and circumferential retention of the second seal ring (64) is provided by an elastomeric toric (68) which is arranged radially between the second seal ring (64) and a retaining ring structure (46) which constitutes a part of the relatively rotatable structure (14). Axially facing surfaces (82,84,96) of the second seal ring (64) and the sealing toric (68) have areas in the axial direction which cause the second seal ring (64) to be pressure balanced in the axial direction by fluid pressure exerted thereon. A Belleville spring (88) is arranged axially between the retaining ring structure (46) and the second seal ring (64) and is prestressed to provide a constant axial force against the second seal ring (64). The toric (68) is engaged only on its radial extremes and thus may readily roll about its circular, central axis, but, when suitably radially compressed, will not readily slide circumferentially or axially relative to the second seal ring (64) and retaining ring structure (46).

Pressure balanced - constant engagement force seal

PCT No. PCT/WS80/00166 Sec. 371 Date Feb. 19, 1980 Sec. 102(e) Date Feb. 19, 1980 PCT Filed Feb. 19, 1980 A joint sealing structure (12) including an annular seal ring (23) having a sealing portion (28) provided with a sealing lip (31) having a dynamic seal engagement with a joint member sealing surface (18) at all times. The sealing portion is carried on a connecting portion (30) of the seal ring which, in turn, is provided with a base portion (29) mounted in the counterbore of the seal space (15). The stiffener (26) is connected by a connecting portion (27) to a base (25) press fitted in the counterbore surface (20). The base defines an inturned flange (35) providing a bearing for a Belleville spring (24). The Belleville spring is provided with a radial inner portion engaging projecting portions (33) of the stiffener for biasing the sealing portion (28) and lip (31) thereof axially toward the sealing surface (18). The diaphragm is a one-piece element including the stiffener, connecting and base portions and stiffener portion (26) is molded integrally into the sealing portion (28) of the seal ring. The stiffener may be provided with a plurality of distributed openings (38) for providing a positive mechanical bond of the molded sealing portion (28) to the stiffener (26). The Belleville spring may be arranged to pass over center in the range of axial movement between the joint members so as to provide an effectively flat spring rate and thereby provide a stabilized sealing force of the lip (31) against the sealing surface (18).

Joint sealing structure

PCT No. PCT/US79/00505 Sec. 371 Date July 16, 1979 Sec. 102(e) Date July 16, 1979 PCT Filed July 16, 1979 PCT Pub. No. WO81/00293 PCT Pub. Date Feb. 5, 1981 A sealing structure (10,110) for use in a joint (11) having a first member (12) axially movable relative to a second member (14). The first member defines a recess (13) receiving the sealing structure which includes an annular seal ring (19,119) having a radially outer annular base portion (20,120) fitted in the recess, a sealing portion (21,121) having a lip (22,122) engaging a surface (15) of the movable member (14) confronting the recess (13). The sealing portion is provided with a stiffener which is bonded or partially encapsulated therein and provided with axially inwardly projecting tongues (30,130) engaged by a spring structure (24,124). In the illustrated embodiment, the spring structure includes one or more Belleville springs (25,26,125) received within the base portion (20,120) of the seal ring and having outer portions (27,127) axially inwardly engaging a flange (32,132) inturned by the axially inner portion of the base. The Belleville springs are arranged to deflect past the flat disposition thereof in the range of movement between the joint members so as to provide an effectively minimum variation in the sealing force applied thereby.

Seal with stiffened force-transmitting portion

PCT No. PCT/US79/00844 Sec. 371 Date Oct. 15, 1979 Sec. 102(e) Date Oct. 15, 1979 PCT Filed Oct. 15, 1979 A joint sealing structure (19,119,219) for use in sealing relatively axially movable members (11,14) of a joint (10) over a wide range of such axial movement. The sealing structure includes a seal ring (20,120,220) having a sealing lip (21,121,221) having a maintained dynamic seal with a sealing surface (22) of one of the joint members. A stiffener (23,123,223) is provided for transferring biasing force from a spring means (29,129,229) to the sealing lip. The stiffener may be provided with a flexible connecting portion (27,127,227) permitting free movement of the sealing lip under the biasing action of the spring means over the range of movement between the joint members. In one form, a base (28) may be provided to which the connecting portion (27) is mounted, the base being fitted into the counterbore 817) of the joint member so as to provide a static seal therebetween. The base may be provided with a turned flange for carrying the outer portion (33) of the spring (30) for free movement of the spring means in maintaining the biasing action. The spring means may comprise Belleville spring means arrangement to pass over center over the range of movement of the joint members so as to provide an effectively constant spring biasing force to the sealing lip.

A shaft seal assembly has an elastomer load ring seated in an annular groove provided in an organic plastic sealing ring. The sealing ring is constructed to provide greater unit loading at the outer edges of the sealing surface than at the remainder of the sealing surface. The end faces of the sealing ring are free from contact with adjacent structure.

Shaft seal

A sealed joint including a first member having a shaft affixed thereto, a second member having a bore receiving the shaft, an annular groove in the first member about the shaft and facing the second member, an annular seal in the groove, a sleeve within the bore and about the shaft and having a radially outwardly extending peripheral flange at the end thereof nearest the first member, the flange engaging the seal, and an axial adjusting device whereby the position of the sleeve within the bore may be axially adjusted to selectively set the pressure of the flange on the seal.

Sealed joint construction

An apparatus and method for vacuum evacuation and pressure filling of a lubricant reservoir are provided which includes a sequence timing and shutoff mechanism for controlling evacuation, testing for air leaks, and filling with lubricant. Visual indication of mechanism performance is provided. A charging gun is adapted for sealingly mating with an opening in the reservoir. Alternatively, a pointed probe utilizable with stoppers of the conventional as well as vented type may be used.

Growing community of inventors

Dunlap, IL, United States of America

Harold L Reinsma