Turbocharger for an internal combustion engine with a hydrodynamic floating bearing

Patent metadata

Field	Value
Publication number	US-11319835-B2
Application number	US-201816954314-A
Country	US
Kind code	B2
Filing date	Dec 21, 2018
Priority date	Dec 22, 2017
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

The invention relates to a turbocharger for an internal combustion engine, comprising a housing (1) with an exhaust-gas-side and an air-side turbine blade (2), a shaft (3) connecting the turbine blades, and at least one radially acting rotary bearing for mounting the shaft (3), wherein the rotary bearing is designed as a hydrodynamic floating bearing, wherein a lubricant flows in a completely surrounding bearing gap (8) of the rotary bearing in the direction of rotation and has a local lubricant pressure, the bearing gap (8) has a contouring (10, 11, 10a, 11a, 12, 13, 14, 15) due to which the at least two local maxima (PM1, PM2) of the lubricant pressure are formed at two defined angular positions (W1, W2) in the direction of rotation.

First claim

The invention claimed is:

1. A turbocharger for an internal combustion engine comprising
a housing ( 1 ) with an exhaust-gas-side turbine blade ( 2 ) and an air-side turbine blade,
a shaft ( 3 ) connecting the turbine blades, and
at least one radially acting rotary bearing for mounting the shaft ( 3 ),
wherein the rotary bearing is designed as a hydrodynamic floating bearing,
wherein a lubricant flows in a completely surrounding bearing gap ( 8 ) of the rotary bearing in the direction of rotation and has a local lubricant pressure,
characterized in that
the bearing gap ( 8 ) has a contouring ( 10 , 11 , 10 a , 11 a , 12 , 13 , 14 , 15 ) due to which at least two local maxima (PM 1 , PM 2 ) of the lubricant pressure are formed at two defined angular positions (W 1 , W 2 ) in the direction of rotation, and
the turbocharger is designed as a multi-scroll turbocharger, wherein the at least two local maxima (PM 1 , PM 2 ) of the lubricant pressure have a respective relative angular position to at least two differently positioned inlet areas ( 4 , 4 a , 5 , 5 a ) of the exhaust-gas-side turbine blade ( 2 ).

2. The device according to claim 1 , characterized in that the angular positions of the maxima (PM 1 , PM 2 ) have a minimal angular spacing from one another of between 140° and 180°.

3. The device according to claim 1 , characterized in that the bearing gap ( 8 ) is supplied with the lubricant via at least two feed holes ( 10 , 11 ).

4. The device according to claim 3 , characterized in that an oil distribution groove ( 10 a , 11 a ) is provided in the area of each of the feed holes ( 10 , 11 ) and extends across a defined angle in the direction of rotation.

5. The device according to claim 3 , characterized in that the angular positions of the local maxima of the lubricant pressure each have an angular spacing (W 1 , W 2 ) of at least 15° from a center of the feed hole ( 10 , 11 ) closest in the direction of rotation.

6. The device according to claim 1 , characterized in that the contouring ( 10 , 11 , 10 a , 11 a , 12 , 13 , 14 , 15 ) of the bearing gap ( 8 ) comprises at least two local minima ( 12 , 13 , 14 , 15 ) of a radial height (H).

7. The device according to claim 6 , characterized in that the radial height (H) of the bearing gap ( 8 ) increases monotonically counter to the direction of rotation, starting from the local minimum ( 12 , 13 ).

8. The device according to claim 6 , characterized in that the bearing is designed as a type of offset bearing.

9. The device according to claim 6 , characterized in that the radial height (H) of the bearing gap ( 8 ) has at least two stepped changes ( 14 , 15 ).

10. The device according to claim 1 , characterized in that the rotary bearing is designed as a fully floating bearing, wherein a bearing bush ( 7 ) is float mounted on the one side with respect to the shaft ( 3 ) and on the other side with respect to the housing ( 1 ).

11. The device according to claim 10 , characterized in that the contouring ( 10 , 11 , 10 a , 11 a , 12 , 13 , 14 , 15 ) is designed on the housing ( 1 ) and the local maxima (PM 1 , PM 2 ) of the lubricant pressure occur between the bearing bush ( 7 ) and the housing ( 1 ).

12. The device according to claim 1 , characterized in that the rotary bearing is designed as a semi-floating bearing, wherein the bearing bush ( 7 ) is arranged rotationally fixed on the housing ( 1 ) and the contouring ( 10 , 11 , 10 a , 11 a , 12 , 13 , 14 , 15 ) of the bearing gap ( 8 ) is designed on the bearing bush ( 7 ).

13. The device according to claim 1 , characterized in that the at least two local maxima (PM 1 , PM 2 ) are precisely two local maxima (PM 1 , PM 2 ).

14. The device according to claim 1 , wherein the turbocharger is designed as a dual volute turbocharger.

15. The device according to claim 4 , wherein the oil distribution groove ( 10 a , 11 a ) is formed as a moon groove.

16. The device according to claim 5 , characterized in that the angular positions of the local maxima of the lubricant pressure each have an angular spacing (W 1 , W 2 ) of at least 30° from a center of the feed hole ( 10 , 11 ) closest in the direction of rotation.

17. The device according to claim 2 , characterized in that the angular positions of the maxima (PM 1 , PM 2 ) have a minimal angular spacing from one another of between 160° and 180°.

Assignees

• Borgwarner Inc

Inventors

• Injac Ivan

Classifications

• F16C33/107 Primary

  Grooves for generating pressure · CPC title

• F01D25/18

  Lubricating arrangements (of machines or engines in general F01M) · CPC title

• F05D2240/53

  Hydrodynamic or hydrostatic bearings · CPC title

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F16C33/1065

  Grooves on a bearing surface for distributing or collecting the liquid · CPC title