Exhaust-gas turbocharger

• US 9,638,059 B2
• Filed: 05/09/2011
• Issued: 05/02/2017
• Est. Priority Date: 05/14/2010
• Status: Active Grant

• Current Assignee: BorgWarner Incorporated
• Original Assignee: BorgWarner Incorporated
• Inventors: Becker, Martin, Seiler, Andr
• Primary Examiner(s): Stigell, Theodore
• Assistant Examiner(s): Hoffmann, Jon
• Application Number:
  US13/695,920
• Publication Number:
  US 20130108483A1
• Time in Patent Office: 2,185 Days
• Field of Search: 417407, 4174771, 41747711, 4174779, 4174774, 4174776, 4174778, 4174772, 417360, 417476, 417475, 415111-112, 415229, 384145
• CPC Class Codes: F01D 25/16 Arrangement of bearings; Supporting or mounting bearings in casings bearings per se F16C
• CPC Class Codes: F01D 25/166 Sliding contact bearing gas bearings F01D25/22
• CPC Class Codes: F01D 25/186 for sliding contact bearing
• CPC Class Codes: F02B 39/00 Component parts, details, or accessories relating to, driven charging or scavenging pumps, not provided for in groups F02B33/00 - F02B37/00
• CPC Class Codes: F05D 2220/40 in turbochargers
• CPC Class Codes: F05D 2230/50 Building or constructing in particular ways
• CPC Class Codes: F05D 2250/70 Shape
• CPC Class Codes: F16C 17/02 for radial load only
• CPC Class Codes: F16C 17/18 with floating brasses or brushing, rotatable at a reduced speed F16C17/03, F16C17/06 take precedence
• CPC Class Codes: F16C 17/26 Systems consisting of a plurality of sliding-contact bearings
• CPC Class Codes: F16C 2240/70 Diameters; Radii
• CPC Class Codes: F16C 2360/24 Turbochargers in general F02C6/12
• CPC Class Codes: F16C 33/1065 Grooves on a bearing surface for distributing or collecting the liquid

Abstract

In the generic exhaust-gas turbocharger, the turbine-side and compressor-side radial bearing bush are of identical design. A more compact bearing space, and improvements in acoustics and rotor dynamics, are achieved by providing different bearings on the turbine and compressor sides.

Claims

1. An exhaust-gas turbocharger (1) having

a compressor (2) comprising a compressor housing;

a turbine (3) comprising a turbine housing;

a bearing housing (4)

which is connected at one end to the compressor housing and at the other end to the turbine housing, and

which has an oil supply, and which has an oil collecting chamber (6) at a turbine-side end (5) and

which has a bearing arrangement (7) for a rotor shaft (8), which bearing arrangement comprises;

turbine-side and compressor-side receiving bores (9″

, 10″

),

a compressor-side bearing bush (9) with a radially inner bearing surface forming a gap with the rotor shaft (8) and a radially outer circumferential surface facing the compressor-side receiving bore (9″

), and

a turbine-side bearing bush (10) which is spaced apart axially from the compressor-side bearing bush (9) and which has a radially inner bearing surface (11) forming a gap with the rotor shaft (8) and a radially outer circumferential surface (12) facing the turbine-side receiving bore (10″

),

wherein

the inner axial bearing surface width of the compressor-side bearing bush (9) differs from the inner axial bearing surface width of the turbine-side bearing bush (10),

the outer axial bearing surface width of the compressor-side bearing bush (9) differs from the outer axial bearing surface width of the turbine-side bearing bush (10) or

the inner axial bearing surface width of the compressor-side bearing bush (9) differs from the inner axial bearing surface width of the turbine-side bearing bush (10) and the outer axial bearing surface width of the compressor-side bearing bush (9) differs from the outer axial bearing surface width of the turbine-side bearing bush (10).

2. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein the outer diameter of the rotor shaft (8) in the region of the compressor-side bearing bush (9′

) and/or the outer diameter of the rotor shaft (8) in the region of the turbine-side bearing bush (10) is larger than the rotor shaft diameter between the bearing bushes (9, 10).

3. The exhaust-gas turbocharger (1) as claimed in claim 2, wherein the diameter enlargement is realized by the provision of a slight bevel or by the provision of a shaft shoulder.

4. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein the compressor-side bearing bush (9) outer diameter is larger or smaller than the outer diameter of the turbine-side bearing bush (10).

5. The exhaust-gas turbocharger (1) as claimed in claim 4, wherein the inner diameter of the compressor-side bearing bush (9) is larger or smaller than the inner diameter of the turbine-side bearing bush (10).

6. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein the inner bearing surfaces (11) and/or the outer bearing surfaces (17) of the bearing bushes (9, 10) are of different design.

7. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein receiving bores (9″

, 10″

) for the bearing bushes (9, 10) in the bearing housing (4) are of different design with regard to bore diameter and/or bore width.

8. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein inner surfaces of the receiving bores of the bearing housing (4) are of different design.

9. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein the turbine-side bearing bush (10) extends into the region of the oil collecting chamber (6).

10. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein the radially inner bearing surface (11) of the compressor-side bearing bush (9) or the turbine-side bearing bush (10) is split into two spaced-apart bearing surface regions (13, 14).

11. The exhaust-gas turbocharger (1) as claimed in claim 10, wherein the bearing surface regions (13, 14) are separated from one another by a radially outwardly recessed clearance (15).

12. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein the turbine-side bearing bush (10) is of symmetrical design with a continuous outer circumferential surface (12).

13. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein an outer circumferential surface (12) of the turbine-side bearing bush (10) is split into two outer circumferential surface regions (17, 18) by a shoulder (16), one outer circumferential region (17) having a greater outer diameter, the other outer circumferential region (18) having a smaller outer diameter.

14. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein the bearing bushes (9, 10) are held spaced apart axially along the rotor shaft (8) by a spacer arrangement (19).

15. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein the bearing bushes (9, 10), spaced apart axially by means of a spacer arrangement (19), are combined to form one component.

16. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein inner surfaces of the receiving bores of the bearing housing (4) are of different design and are provided with a sickle-shaped groove (20) arranged on circumferential segments.

17. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein the inner axial bearing surface width of the compressor-side bearing bush (9) differs from the inner axial bearing width of the turbine-side bearing bush (10).

18. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein the outer axial bearing surface width of the compressor-side bearing bush (9) differs from the outer axial bearing surface width of the turbine-side bearing bush (10).

19. The exhaust-gas turbocharger (1) as claimed in claim 1, wherein the inner and outer axial bearing surfaces width of the compressor-side bearing bush (9) differ from the inner and outer axial bearing surfaces width of the turbine-side bearing bush (10).