Granted Patent B2

US 8,961,128 · App. 12/547,740 · Granted Feb 24, 2015

Abstract

Claims (27)

1. A center housing rotating assembly for a turbocharger comprising:

a turbine wheel;

a compressor wheel;

a center housing ( 510 ) that comprises a through bore ( 515 ), extending from a compressor end to a turbine end along a bore axis;

a bearing assembly ( 530 ) positioned in the through bore ( 515 ) wherein the bearing assembly ( 530 ) comprises an outer race ( 532 ) that comprises a raceway defined axially from a low shoulder to a high shoulder and that comprises keyways ( 535 , 535 ′) with an axial keyway depth defined from an axial end of the outer race ( 532 ) to an axial position that is less than that of the low shoulder of the raceway, the keyways ( 535 , 535 ′) radially inset from an inset diameter (D Inset ) of the outer race ( 532 ) that is less than an adjacent outer diameter (D Outer ) of the outer race ( 532 ) that comprises an axial span over the raceway, wherein the inset diameter comprises an axial extent defined from the end of the outer race to an axial position that is less than that of the low shoulder of the raceway, and wherein the adjacent outer diameter (D Outer ), being less than a diameter of the through bore ( 515 ) of the center housing ( 510 ), defines a squeeze film clearance for formation of a lubricant squeeze film between the outer race ( 532 ) and the center housing ( 510 ); and

a plate ( 570 ) attached to the center housing wherein the plate comprises axially extending keys ( 578 , 578 ′), each of the keys ( 578 , 578 ′) being received by a respective one of the keyways ( 535 , 535 ′) to an axial depth less than the axial keyway depth wherein the keyways ( 578 , 578 ′) restrict rotation of the outer race ( 532 ) of the bearing assembly ( 530 ) in the through bore ( 515 ) of the center housing ( 510 ) while enabling an amount of radial freedom of the outer race ( 532 ) in the defined squeeze film clearance.

2. The center housing rotating assembly of claim 1 wherein the outer race ( 532 ) comprises an asymmetric outer race and wherein the keys ( 578 , 578 ′) in conjunction with the keyways ( 535 , 535 ′) azimuthally locate the outer race with respect to one or more features of the through bore ( 515 ).

3. The center housing rotating assembly of claim 2 wherein one of the one or more features of the through bore comprises a lubricant well, wherein the outer race ( 532 ) comprises lubricant jets and wherein the keys ( 578 , 578 ′) in conjunction with the keyways ( 535 , 535 ′) azimuthally locate the lubricant jets with respect to the lubricant well.

4. A method for locating an outer race of a bearing in a bore of a housing, the method comprising:

inserting the bearing in the bore of the housing wherein an outer diameter of the bearing and an inner diameter of the bore define a squeeze film clearance for lubricant squeeze film formation;

attaching a plate to the housing to at least partially axially locate the bearing in the bore of the housing;

restricting rotation of the outer race of the bearing in the bore of the housing by contacting an axially extending key and a keyway while enabling an amount of radial freedom of the outer race in the defined squeeze film clearance,

wherein the plate comprises the key and wherein the bearing comprises a raceway defined axially from a low shoulder to a high shoulder and comprises the keyway, wherein the keyway comprises an axial keyway depth defined axially from an axial end of the outer race to an axial position that is less than that of the low shoulder of the raceway, wherein the keyway is radially inset from an inset diameter of the outer race that is less than an adjacent outer diameter of the outer race that comprises an axial span over the raceway, wherein the inset diameter comprises an axial extent defined from the end of the outer race to an axial position that is less than that of the low shoulder of the raceway, and wherein the key comprises an axial depth that is less than the axial keyway depth.

5. The method of claim 4 wherein the contacting azimuthally locates one or more lubricant jets of the outer race of the bearing with respect to a lubricant well of the housing.

6. The center housing rotating assembly of claim 1 wherein the inset diameter extends from the axial end of the outer race to at least an axial depth of the keyways.

7. The center housing rotating assembly of claim 1 wherein an opposing axial end of the bearing cartridge does not comprise a section of the outer race with an inset diameter.

8. A turbocharger comprising:

a turbine wheel;

a turbine housing;

a compressor wheel;

a compressor housing;

a center housing that comprises a through bore, extending from a compressor end to a turbine end along a bore axis wherein the turbine housing and the compressor housing are coupled to the center housing;

a bearing assembly positioned in the through bore wherein the bearing assembly comprises an outer race that comprises a raceway defined axially from a low shoulder to a high shoulder and that comprises keyways with an axial keyway depth defined from an axial end of the outer race to an axial position that is less than that of the low shoulder of the raceway, the keyways radially inset from an inset diameter of the outer race that is less than an adjacent outer diameter of the outer race that comprises an axial span over the raceway, wherein the inset diameter comprises an axial extent defined from the end of the outer race to an axial position that is less than that of the low shoulder of the raceway, and wherein the adjacent outer diameter, being less than a diameter of the through bore of the center housing, defines a squeeze film clearance for formation of a lubricant squeeze film between the outer race and the center housing; and

a plate attached to the center housing wherein the plate comprises axially extending keys, each of the keys being received by a respective one of the keyways to an axial depth that is less than the axial keyway depth wherein the keys restrict rotation of the outer race of the bearing assembly in the through bore of the center housing while enabling an amount of radial freedom of the outer race in the defined clearance.

9. The center housing rotating assembly of claim 1 wherein the plate axially locates the outer race by contact between a surface at the axial end of the outer race and a surface of the plate.

10. The method of claim 4 further comprising axially locating the outer race by contacting a surface at the axial end of the outer race and a surface of the plate.

11. The turbocharger of claim 8 wherein the plate axially locates the outer race by contact between a surface at the axial end of the outer race and a surface of the plate.

Assignments (7)