Turbine wheel

Abstract

A turbine wheel (4) having a hub (29); a multiplicity of turbine wheel blades (30) arranged around the hub (29); a turbine wheel back wall (31) which is arranged on the hub (29) adjacent to an edge region (32) of the turbine wheel blades (30); wherein the wall thickness (W) of the turbine wheel (4) back wall is reduced in regions.

Claims

1. A turbine wheel (4) having a hub (29) including a radially enlarged disc-like portion of the hub, the disc-like portion defining a floor on one side and a backwall (31) on the other side and a radially outer edge, with a wall defined between the floor and the backwall (31); and a multiplicity of turbine wheel blades (30) arranged around the hub (29); wherein the radially outer edge has regions with a first wall thickness (W) and regions with a reduced wall thickness compared to the first wall thickness (W) of the radially enlarged disc-like portion of the hub, the turbine wheel back wall (31) regions of reduced thickness are defined by pockets (33) which are open radially outwardly, and the pockets (33) do not extend through the entire wall thickness (W) of the turbine wheel backwall (31).

2. The turbine wheel as claimed in claim 1, wherein the pockets (33) are arranged on the outer edge region of the turbine wheel backwall (31) between blades.

3. An exhaust-gas turbocharger (1) having a turbine housing (2) in which is arranged a turbine wheel (4) which has: a hub (29) including a radially enlarged disc-like portion of the hub, the disc-like portion defining a floor on one side and a backwall (31) on the other side and a radially outer edge, with a wall defined between the floor and the backwall (31); and a multiplicity of turbine wheel blades (30) arranged around the hub (29); wherein the radially outer edge has regions with a first wall thickness (W) and regions with a reduced wall thickness compared to the first wall thickness (W) of the radially enlarged disc-like portion of the hub, and the pockets (33) do not extend through the entire wall thickness (W) of the turbine wheel backwall (31).

4. The exhaust-gas turbocharger as claimed in claim 3, wherein the turbine wheel back wall (31) has at least one pocket (33) which is open radially outwardly.

5. The exhaust-gas turbocharger as claimed in claim 3, wherein the pockets (33) are arranged on the radially outer edge of the turbine wheel backwall (31).

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

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

(2) FIG. 1 shows a perspective sectional illustration through an exhaust-gas turbocharger according to the invention,

(3) FIG. 2 shows a perspective illustration of a turbine wheel according to the invention, and

(4) FIG. 3 shows a sectional illustration through a partial region of the turbine wheel as per FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

(5) FIG. 1 illustrates an exhaust-gas turbocharger 1 according to the invention which has a turbine housing 2 in which a turbine wheel 4 is arranged.

(6) With regard to all other components of the exhaust-gas turbocharger 1 according to the invention, reference may be made to the list of reference signs provided at the end of this description, because a detailed description of said elements is not important for explaining the principles of the present invention.

(7) The turbine wheel 4 according the invention is illustrated in FIG. 2. Said turbine wheel 4 has a hub 29 around which are arranged a multiplicity of turbine wheel blades, of which, in FIG. 2, one turbine wheel blade is identified, representatively of all of the blades, by the reference sign 30.

(8) The turbine wheel 4 furthermore has a turbine wheel back wall 31 which is arranged on the hub 29 at an edge region 32 of the turbine wheel blades 30. As shown by FIG. 2 in conjunction with FIG. 1, the edge region 32 is that region which, in the installed state of the turbine wheel 4, faces toward a shaft 34, to which shaft the turbine wheel 4 is fastened, of the exhaust-gas turbocharger 1.

(9) As can be seen viewing FIGS. 2 and 3 together, for the reduction of the wall thickness W of the turbine wheel back wall 31 in regions, it is provided in the example that a multiplicity of pockets which are open on one side are arranged in the turbine wheel back wall 31, of which pockets one pocket 33 is denoted, representatively of all of the pockets, in FIGS. 2 and 3. The pockets 33 may be of various forms, for example semi-circular, and do not extend through the entire wall thickness W, as can be seen from the reduced wall thickness WR, indicated in FIG. 3, in the region of the pockets 33.

(10) The pockets 33 are furthermore arranged at the outer circumference (inlet circumference) 35 of the turbine wheel 4 or of the turbine wheel back wall 31.

(11) The number of pockets 33, and also the depth thereof in the wall thickness W of the turbine wheel back wall 31, may be reduced or increased depending on the application.

(12) In addition to the above written disclosure of the invention, reference is hereby explicitly made to the illustrative presentation of the invention in FIGS. 1 to 3.

LIST OF REFERENCE SIGNS

(13) 1 Turbocharger 2 Turbine housing 3 Compressor housing 4 Turbine wheel 5 Unison ring 6 Blade bearing ring 7 Adjusting blades 8 Rotary axles 9 Supply duct 10 Axial connector 11 Actuating device 12 Control casing 13 Free space for adjusting blades 7 14 Plunger element 15 Annular part of the turbine housing 2 16 Spacer/spacer cam 17 Compressor wheel 18 Guide grate 28 Bearing housing 29 Hub 30 Turbine wheel blades 31 Turbine wheel back wall 32 Edge 33 Pockets 34 Shaft W Wall thickness of the turbine wheel back wall W.sub.R Reduced wall thickness R Axis of rotation