Fluid lubricated floating bushing seal

Claim 2

A shaft seal assembly positioned between a roating shaft and a housing therefore comprising: a cylindrical rotor portion affixed to a shaft having an axis of rotation; a floating bushing element radially enclosing said rotor wherein adjacent bearing surfaces on said rotor and said bushing define a fluid lubricated interface therebetween, one of said bearing surfaces consists of a plurality of first and second grooves extending substantially parallel with said shaft axis and arranged in an axially overlapping and offset relationship with each other, wherein a first groove extends between two adjacent second grooves, and the other of said bearing surfaces being a compliant surface cooperating with said first and second grooves to promote flow of fluid from said first grooves to said second grooves; and means for maintaining a fluid seal between said bushing and a housing while accomodating radial displacements of said bushing relative to the housing.

Claim 3

The assembly according to claim 1, wherein said compliant surface is formed of material selected from the group of neoprene, polyurethane, polyimide resins, polyamide resins, carbon-graphites and Buna-N.

Claim 4

The assembly according to claim 1, wherein said grooves have a depth of about one-thirty-second of an inch and said compliant surface has a depth of about one-eighth of an inch.

Claim 5

The assembly according to claim 1, wherein said one surface containing said first and second grooves includes first and second axially spaced surface edges, said first grooves extending axially of said one surface from said first surface edge and terminating short of said second surface edge and said second grooves extending axially of said one surface from said second surface edge and terminating short of said first surface edge.

Claim 6

The assembly according to claim 4, wherein said first and second grooves axially overlap in spaced apart parallel relationship from about twenty percent to about fifty percent of the distance between said first and second edges.

Claim 7

The assembly according to claim 4, wherein said first and second grooves axially overlap in spaced apart parallel relationship from about fifteen percent to about fifty percent of one-half the sum of the average length of the first and the second grooves.

Claim 8

The assembly according to claim 1, wherein said first and second grooves vary in length.

Claim 9

The assembly according to claim 1, wherein said means for maintaining a fluid seal comprises a spring means attached to one end portion of said bushing and connected to said housing for biasing the other end portion of said bushing against the housing to form a fluid seal therebetween.

Claim 10

A shaft seal assembly positioned between a rotating shaft and a housing enclosing the shaft comprising: a cylindrical rotor concentrically affixed to the shaft, the cylindrical rotor having first and second axially spaced radially extending surface portions and an axially extending circumferential surface portion extending between the first and second radial surface portions, the circumferential surface being provided with first and second axially extending grooves arranged in a parallel and offset relationship with each other so that a first groove extends axially between two adjacent second grooves, the first grooves extending axially from the first radial surface portion and terminating short of the second radial surface portion, and the second grooves extending axially from the second radial surface and terminating short of the first radial surface portion; a floating bushing element having an inner axially extending bearing surface, the bushing element radially enclosing the rotor so that the circumferential surface on the rotor and the bearing surface on the bushing element define a fluid lubricated interface therebetween, and the bearing surface having a compliant surface cooperating with the first and second grooves to promote the flow of fluid from the first grooves to the second grooves; and means for maintaining a fluid seal between the bushing element and the housing while accomodating radial displacements of the bushing element relative to the housing, the fluid seal means including a spring means attached to one end portion of the bushing element and connected to the housing for biasing the other end portion of the bushing element against the housing to form a fluid seal therebetween.

Claim 11

A shaft seal assembly positioned between a rotating shaft and a housing enclosing the shaft comprising: a cylindrical rotor concentrically affixed to the shaft, the cylindrical rotor having first and second axially spaced radially extending surface portions and an axially extending circumferential surface portion extending between the first and second radial surface portions, the circumferential surface being provided with first and second axially extending grooves arranged in a parallel and offset relationship with each other so that a first groove extends axially between two adjacent second grooves, the first grooves extending axially from the first radial surface portion and terminating short of the second radial surface portion, and the second grooves extending axially from the second radial surface and terminating short of the first radial surface portion; a floating bushing element having an inner axially extending bearing surface, the bushing element radially enclosing the rotor so that the circumferential surface on the rotor and the bearing surface on the bushing element define a fluid lubricated interface therebetween, and the bearing surface having a compliant surface cooperating with the first and second grooves to promote the flow of fluid from the first grooves to the second grooves; and means for maintaining a fluid seal between the bushing element and the housing while accomodating radial displacements of the bushing element relative to the housing, the fluid seal means including a spring means attached to one end portion of the bushing element and connected to the housing for biasing the other end portion of the bushing element against the housing to form a fluid seal therebetween.

Claim 12

The assembly according to claim 9, wherein the compliant surface is formed of material selected from the group of neoprene, synthetic and natural rubber, polyurethane, polyimide resins, polyamide resins, carbon-graphites, and Buna-N.

Claim 13

The assembly according to claim 10, wherein the first and second grooves axially overlap in spaced apart parallel relationship of from about twenty percent to about fifty percent of the distance between the first and second radial surfaces.

Claim 14

The assembly according to claim 11, wherein the grooves have a depth of about one-thirty-second of an inch and the compliant surface has a thickness of about one-eight of an inch.

Claim 15

The assembly according to claim 9, wherein the first and second grooves axially overlap in spaced apart parallel relationship of from about twenty percent to about fifty percent of the distance between the first and second radial surfaces.

Claim 16

The assembly according to claim 9, wherein the first and second grooves axially overlap in spaced apart parallel relationship from about fifteen percent to about fifty percent of one-half the sum of the average length of the first and second grooves.

Claim 17

A shaft seal assembly for providing controlled leakage of fluid from a high fluid pressure side of the seal assembly to a lower fluid pressure side of the seal assembly, comprising: two parts movable relative to each other; and bearing surfaces on the respective parts facing each other to define a fluid lubricated interface therebetween, wherein one of the surfaces contains a plurality of first and second grooves arranged in a substantially parallel and offset relationship with each other so that a first groove extends between adjacent second grooves, the first grooves communicating with the high pressure side of the seal assembly and terminating short of the lower pressure side of the seal assembly, and the second grooves communicating with the lower pressure side of the seal assembly and terminating short of the high pressure side of the seal assembly so that fluid flows from the first grooves to the second grooves as the bearing surfaces of the two parts move relative to each other.

Claim 18

A shaft seal assembly for providing controlled leakage of fluid from a high fluid pressure side of the seal assembly to a lower fluid pressure side of the seal assembly, comprising: two parts movable relative to each other; and bearing surfaces on the respective parts facing each other to define a fluid lubricated interface therebetween, wherein one of the surfaces contains a plurality of first and second grooves arranged in a substantially parallel and offset relationship with each other so that a first groove extends between adjacent second grooves, the first grooves communicating with the high pressure side of the seal assembly and terminating short of the lower pressure side of the seal assembly, and the second grooves communicating with the lower pressure side of the seal assembly and terminating short of the high pressure side of the seal assembly so that fluid flows from the first grooves to the second grooves as the bearing surfaces of the two parts move relative to each other.

Claim 19

The shaft seal assembly according to claim 15, wherein the other of said surfaces comprises a compliant surface means cooperating with the first and second grooves to promote flow of fluid from the first grooves to the second grooves, wherein the compliant surface means is formed of material selected from the group of neoprene, synthetic and natural rubber, polyurethane, polyimide resins, polyamide resins, carbon-graphites, and Buna-N.