Exhaust-gas turbocharger

Abstract

An exhaust-gas turbocharger (1) comprising a housing (2), a turbine wheel (5) with blades (6), a compressor wheel (4) with blades (6), and a shaft (3) which is mounted in the housing (2) and which connects the turbine wheel (5) and compressor wheel (4), wherein, in a gap (7) between the housing (2) and at least one blade (6), a contactless labyrinth seal (8) is formed on the blade (6) and on the housing (2), wherein the labyrinth seal (8) comprises at least one combination of a groove (13) and a projection (14).

Claims

1. An exhaust-gas turbocharger (1) comprising: a housing (2), a turbine wheel (5) with blades (6) adapted for receiving air radially and discharging air axially, a compressor wheel (4) with blades (6) adapted to drawing air in axially and discharging air radially, and a shaft (3) which is mounted in the housing (2) and which connects the turbine wheel (5) and compressor wheel (4), wherein, in a gap (7) between the housing (2) and at least one blade (6), a contactless labyrinth seal (8) is formed on the blade (6) and on the housing (2), wherein the labyrinth seal (8) comprises at least one combination of a groove (13) and a projection (14).

2. The exhaust-gas turbocharger as claimed in claim 1, wherein the labyrinth seal (8) comprises at least one groove (13) in the housing (2) and one projection (14), which projects into the groove (13), on the blade (6), and/or at least one groove (13) in the blade (6) and one projection (14), which projects into the groove (13), on the housing (2).

3. The exhaust-gas turbocharger as claimed in claim 1, wherein the labyrinth seal (8) comprises multiple combinations of a groove (13) and a projection (14) on a blade (6).

4. The exhaust-gas turbocharger as claimed in claim 1, wherein the groove (13) and/or the projection (14) is arranged at a blade tip (15) of the blade (6).

5. The exhaust-gas turbocharger as claimed in claim 1, wherein the groove (13) and/or the projection (14) is arranged on each blade (6) of the compressor wheel (4) or turbine wheel (5).

6. The exhaust-gas turbocharger as claimed in claim 1, wherein the groove (13) and/or the projection (14) is arranged in that half of the blade (6) of the compressor wheel (4) which faces toward a compressor outlet (9).

7. The exhaust-gas turbocharger as claimed in claim 1, wherein the groove (13) and/or the projection (14) is arranged in that half of the blade (6) of the turbine wheel (5) which faces toward a turbine inlet (10).

8. The exhaust-gas turbocharger as claimed in claim 1, wherein the groove (13) and/or the projection (14) is trapezoidal.

9. The exhaust-gas turbocharger as claimed in claim 1, wherein the groove (13) and/or the projection (14) is arranged in the downstream half of the blade (6) of the compressor wheel (4).

10. The exhaust-gas turbocharger as claimed in claim 1, wherein the groove (13) and/or the projection (14) is arranged in the upstream half of the blade (6) of the turbine wheel (5).

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) Further details, advantages and features of the invention become apparent from the following description of an exemplary embodiment with reference to the drawing, in which:

(2) FIG. 1 shows a schematically simplified sectional view of an exhaust-gas turbocharger according to the invention as per an exemplary embodiment,

(3) FIG. 2 shows a detail of the exhaust-gas turbocharger according to the invention as per a first exemplary embodiment,

(4) FIG. 3 shows a compressor wheel of the exhaust-gas turbocharger according to the invention as per the first exemplary embodiment,

(5) FIG. 4 shows a detail of the exhaust-gas turbocharger according to a second embodiment the invention, and

(6) FIG. 5 shows a detail of the exhaust-gas turbocharger according to a third embodiment the invention.

DETAILED DESCRIPTION OF THE INVENTION

(7) An exemplary embodiment will be explained below on the basis of FIGS. 1 to 5.

(8) FIG. 1 is a highly simplified illustration of an exhaust-gas turbocharger 1. The exhaust-gas turbocharger 1 comprises a housing 2 in which a shaft 3 is rotatably mounted. A compressor wheel 4 and a turbine wheel 5 are seated in a rotationally conjoint manner on the shaft 3. Both the turbine wheel 5 and also the compressor wheel 4 have in each case multiple blades 6.

(9) The compressor wheel 4 compresses inducted charge air in the direction of a compressor outlet 9. At a turbine inlet 10, exhaust gas flows to the turbine wheel 5 and thus drives the turbine wheel 5, the shaft 3 and the compressor wheel 4.

(10) A gap 7 is formed between the blades 6 and the housing 2.

(11) FIG. 2 shows a detail of the compressor wheel 4 and of the housing 2. According to FIG. 2, the housing 2 may be of multi-part construction. It can be seen that the housing 2 is assembled from a compressor housing 11 and a bearing housing 12.

(12) According to a first embodiment of the invention, to prevent flow loss in the gap 7, the labyrinth seal 8 shown in FIG. 2 is used. The labyrinth seal 8 is composed of a combination of a groove 13 in the compressor housing 2 and a projection 14 on each blade 6. In the example shown, the groove 13 is formed over the full circumference and in a continuous fashion on the inner side of the housing 2, in particular of the compressor housing 11.

(13) According to a second embodiment of the invention, the labyrinth seal 8 shown in FIG. 4 is used. The labyrinth seal 8 is composed of a combination of a grooves 13 on each blade 6 and a projection 14 in the compressor housing 2. In the example shown, the projection 14 is formed over the full circumference and in a continuous fashion on the inner side of the housing 2, in particular of the compressor housing 11.

(14) As an alternative to the first and second embodiments shown in FIGS. 2-4, the labyrinth seal 8 may also have multiple projections 14, 14 and/or in a third embodiment shown in FIG. 5, may have combinations of projections 14 and grooves 13 along a blade tip 15 of a blade 6. Corresponding, complementary grooves 13 and projections 14 are then formed in the housing, such that in each case one projection 14, 14 project into a groove 13, 13.

(15) It is also possible for the labyrinth seal shown to be implemented on the blades 16 of the turbine wheel 5.

(16) In addition to the above written description of the invention, reference is hereby explicitly made to the diagrammatic illustration of the invention in FIGS. 1 to 3 for additional disclosure thereof.

LIST OF REFERENCE SIGNS

(17) 1 Exhaust-gas turbocharger 2 Housing 3 Shaft 4 Compressor wheel 5 Turbine wheel 6 Blades 7 Gap 8 Labyrinth seal 9 Compressor outlet 10 Turbine inlet 11 Compressor housing 12 Bearing housing 13 Groove 14 Projection 15 Blade tip