Regulating flap arrangement of an exhaust-gas turbocharger

Abstract

A regulating flap arrangement (1) of an exhaust-gas turbocharger (3) having a flap shaft (5), which is guided by means of a bushing (10) in the turbine housing (2). A shaped sealing ring (13), as viewed in cross section, has at least one cavity (14). The shaped sealing ring (13) bears simultaneously against the first sealing surface (11) and against the second sealing surface (12), and in order to impart its sealing action, is compressed and deformed in the axial direction (15) of the flap shaft (5).

Claims

1. A regulating flap arrangement (1) of an exhaust-gas turbocharger (3) provided with a turbine housing (2), having a flap plate (4), and having a flap shaft (5), which is connected via an outer flap lever (6) to a regulating rod (7) of a drive (8), which is connected via an inner flap shaft lever (9) to the flap plate (4), and which is guided by means of a bushing (10) in the turbine housing (2), the bushing having a first sealing surface (11) on a face-side end of the bushing (10), a second sealing surface (12), which is situated opposite the first sealing surface (11), on the outer flap lever (6) or the inner flap shaft lever (9), and further comprising a shaped compression sealing ring (13) formed from a single bent sheet which, as viewed in cross section, has at least one cavity (14), wherein the shaped sealing ring (13) bears simultaneously with sliding contact against the first sealing surface (11) and with sliding contact against the second sealing surface (12), and wherein the shaped sealing ring (13), in order to impart its sealing action, is compressed and deformed in the axial direction (15) of the flap shaft (5) wherein a groove (19) which is outwardly open in the axial direction (15) and which serves for receiving the shaped sealing ring (13) is formed in the bushing (10).

2. The regulating flap arrangement as claimed in claim 1, wherein the shaped sealing ring (13) is, by means of two legs (17, 18) which are non-parallel with respect to one another, of V-shaped form as viewed in cross section, wherein the shaped sealing ring (13) bears only with the free ends of the legs (17, 18) against the first and second sealing surfaces (11, 12).

3. The regulating flap arrangement as claimed in claim 1, wherein the shaped sealing ring (13) is S-shaped as viewed in cross section.

4. The regulating flap arrangement as claimed in claim 1, wherein the first sealing surface (11) is arranged parallel to the second sealing surface (12).

5. The regulating flap arrangement as claimed in claim 1, wherein the shaped sealing ring (13) is composed of metal.

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 of an exhaust-gas turbocharger according to the invention,

(3) FIG. 2 shows a detail view of a regulating flap arrangement according to the invention as per a first exemplary embodiment,

(4) FIG. 3 shows a detail view of the regulating flap arrangement according to the invention as per a second exemplary embodiment,

(5) FIG. 4 shows a detail view of the regulating flap arrangement according to the invention as per a third exemplary embodiment, and

(6) FIG. 5 shows a regulating flap arrangement according to the prior art.

DETAILED DESCRIPTION OF THE INVENTION

(7) FIG. 1 illustrates an exhaust-gas turbocharger 3 which has a turbine housing 2 in which a regulating flap arrangement 1 according to the invention, which will be explained in more detail with reference to FIGS. 2 to 4, can be arranged.

(8) FIG. 1 shows the basic design of the regulating flap arrangement 1 composed of a flap plate 4 for opening and closing a wastegate duct. The flap plate 4 is connected via an inner flap shaft lever 9 to a flap shaft 5. Said flap shaft 5 extends through the turbine housing 2 to the outside. An outer flap lever 6 is fastened to the outer end of the flap shaft 5. The flap lever 6 is in turn connected to a regulating rod 7. The regulating rod 7 is moved by means of a drive 8.

(9) FIG. 2 shows the first exemplary embodiment of the regulating flap arrangement 1 in detail. According to FIG. 2, a bushing 10 is situated in the turbine housing 2. The flap shaft 5 is rotatably received in said bushing 10. An axial direction 15 and a radial direction 16 are defined with reference to the flap shaft 5. A groove 19 is formed on the face-side end of the bushing 10. In this exemplary embodiment, the groove 19 is outwardly open in the radial direction 16 and is outwardly open in the axial direction 15. A shaped sealing ring 13 is arranged in the groove 19.

(10) A face-side end of the bushing 10 constitutes a first sealing surface 11. A second sealing surface 12 is situated opposite said first sealing surface 11. The second sealing surface 12 is formed on the flap lever 6. The shaped ring 13 provides sealing between said two sealing surfaces 11, 12.

(11) In this exemplary embodiment, the shaped sealing ring 13 is of V-shaped form. The V-shaped form comprises a first leg 17 and a second leg 18 as viewed in cross section. Said two legs 17, 18 are not parallel to one another, such that each leg 17, 18 has a free end and the other ends of the legs 17, 18 are connected to one another. The free ends of the legs 17, 18 bear against the sealing surfaces 11, 12. The sealing action arises as a result of an axial compression and deformation of the shaped sealing ring 13 in the axial direction 15. As a result of said deformation, a stress is generated in the shaped sealing ring 13 such that the shaped sealing ring 13 presses its legs 17, 18 against the sealing surfaces 11, 12.

(12) The groove 19 has a groove depth 20 in the axial direction 15. The groove depth 20 is selected such that an excessively intense compression of the shaped sealing ring 13 is avoided. Specifically, before the shaped sealing ring 13 is destroyed, the flap lever 6 abuts against the bushing 10 and the shaped sealing ring 13 is securely received within the groove 19.

(13) The shaped sealing ring 13 has a cavity 14. Owing to said cavity 14, the shaped sealing ring 13 differs significantly from a simple seal of disk-shaped form. The cavity 14 is important for attaining an adequate deformation of the shaped sealing ring 13 when the latter is compressed, and thus also building up an adequate stress in the shaped sealing ring 13.

(14) FIG. 3 shows the regulating flap arrangement 1 as per the second exemplary embodiment. Identical or functionally identical components are denoted by the same reference numerals in all of the exemplary embodiments. The first two exemplary embodiments differ in that the shaped sealing ring is of S-shaped form in the second exemplary embodiment. As a result, the shaped sealing ring 13 has two cavities 14. In the second exemplary embodiment, too, the shaped sealing ring 13 is compressed in the axial direction 15.

(15) FIG. 4 shows the regulating flap arrangement 1 as per the third exemplary embodiment. Identical or functionally identical components are denoted by the same reference numerals in all of the exemplary embodiments. In the third exemplary embodiment, the shaped sealing ring 13 is of V-shaped form with two legs 17, 18. By contrast to the first exemplary embodiment, however, the V shape of the shaped sealing ring 13 in the third exemplary embodiment opens in the axial direction 15.

(16) In the third exemplary embodiment, the shaped sealing ring 13 is braced in the radial direction 16. This requires a first radial sealing surface 11a on an inner wall, which faces toward the flap shaft 5, of the bushing 10. The second radial sealing surface 12a is correspondingly defined on the lateral surface of the flap shaft 5. The groove 19 on the face-side end of the bushing 10 thus opens outwardly in the axial direction 15 and inwardly in the radial direction 16. The shaped sealing ring 13 bears again with the free ends of its legs 17, 18 against the sealing surfaces 11a, 12a.

(17) Even though the invention has been explained above on the basis of the example of a regulating flap arrangement, the sealing arrangement may also be used in an exhaust-gas turbocharger with a variable turbine geometry.

(18) 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 4 for additional disclosure thereof.

LIST OF REFERENCE SIGNS

(19) 1 Regulating flap arrangement 2 Turbine housing 3 Exhaust-gas turbocharger 4 Flap plate 5 Flap shaft 6 Outer flap lever 7 Regulating rod 8 Drive 9 Inner flap shaft lever 10 Bushing 11 First sealing surface 11a First radially sealing surface 12 Second sealing surface 12a Second radially sealing surface 13 Shaped seal 14 Cavity 15 Axial direction 16 Radial direction 17 First leg 18 Second leg 19 Groove 20 Groove depth 100 Regulating flap arrangement according to the prior art 101 Piston rings according to the prior art 104 Flap plate according to the prior art 105 Flap shaft according to the prior art 109 Flap shaft lever according to the prior art 110 Bushing according to the prior art