WASTE GATE VALVE ACTUATOR

Abstract

A waste gate valve actuator, that may be used for an exhaust gas turbocharger of a motor vehicle, may have a flap with a base surface to be supported on an edge of an inlet or outlet opening of a waste gate channel and a channel-side elevation, which at least in one cross section along its axial direction exhibits an outer contour with a first section and an adjoining section facing away from the base surface. The outer contour in the first section may have at least one outer tangent that includes a first angle deviating from zero with the axial direction, and in the second section may have at least two outer tangents spaced apart from each other in an axial direction that include the same second angle angle deviating from zero and the first angle with the axial direction, and/or wherein the elevation exhibits in particular a flat front surface facing away from the base surface, which in relation to the base surface-side floor surface of the elevation is offset toward a rotational axis of the flap.

Claims

1-14. (canceled).

15. A waste gate valve actuator, in particular for an exhaust gas turbocharger of a motor vehicle, which has a flap with a base surface to be supported on an edge of an inlet or outlet opening of a waste gate channel and a channel-side elevation, which at least in one cross section along an axial direction has an outer contour with a first section and an adjoining section facing away from the base surface, wherein the outer contour in the first section has at least one outer tangent that includes a first angle (α) deviating from zero with the axial direction, and in the second section has at least two outer tangents spaced apart from each other in the axial direction that includes a second angle (β) angle deviating from zero and the first angle (α) with the axial direction; wherein the elevation has a flat front surface facing away from the base surface, which in relation to a base surface-side floor surface of the elevation is offset toward a rotational axis of the flap.

16. The waste gate valve actuator according to claim 15, wherein the elevation is rotationally symmetrical relative to the axial direction.

17. The waste gate valve actuator according to claim 15, wherein the elevation is sectionally inclined against the axial direction.

18. The waste gate valve actuator according to claim 15, wherein the first section extends over at least 20% of an overall height of the elevation in an axial direction and optionally adjoins the base surface.

19. The waste gate valve actuator according to claim 15, wherein the second section extends over at least 20% of an overall height of the elevation in an axial direction and optionally adjoins a flat front surface of the elevation facing away from the base surface.

20. The waste gate valve actuator according to claim 15, wherein the outer contour in one of the first section and the second section is regionally straight or regionally curved.

21. The waste gate valve actuator according to claim 15, wherein the outer contour between the base surface and a front surface of the elevation is free of kinks with angles measuring more than 45°.

22. The waste gate valve actuator according to claim 15, wherein the base surface is one of flat or offset toward the elevation.

23. The waste gate valve actuator according to claim 15, wherein an outer edge of the base surface is one of offset toward the elevation and offset away from the elevation in an axial direction relative to a transition in the elevation.

24. The waste gate valve actuator according to claim 15, wherein the base surface and elevation are a single piece with each other.

25. The waste gate valve actuator according to claim 15, wherein the flap is movably or rigidly joined with a carrier (4) or designed as a single piece with the latter.

26. An exhaust gas turbocharger, in particular for a motor vehicle, with a turbocharger housing having an inlet or outlet opening of a waste gate channel and a waste gate valve actuator according to claim 15, whose flap can be adjusted to pivot between a closed position, in which its base surface is supported on an edge of the opening, and at least one open position, in which the base surface is spaced apart from the edge.

27. An exhaust gas turbocharger, in particular for a motor vehicle, with a turbocharger housing having an inlet or outlet opening of a waste gate channel and a waste gate valve actuator according to claim 15, whose flap can be adjusted to axially move between a closed position, in which its base surface is supported on an edge of the opening, and at least one open position, in which the base surface is spaced apart from the edge.

28. The exhaust gas turbocharger according to claim 26, wherein the opening and the flap provide free flow through the opening which increases to less of an extent over a travel of the flap between the closed and a maximally open position in a first travel range than in a second travel range, in which the flap is spaced farther away from the opening.

29. The exhaust gas turbocharger according to claim 27, wherein the opening and the flap provide free flow through the opening which increases to less of an extent over a travel of the flap between the closed and a maximally open position in a first travel range than in a second travel range, in which the flap is spaced farther away from the opening.

30. The exhaust gas turbocharger according to claim 28, wherein the opening and the flap provide free flow that increases to more of an extent over the travel in a third travel range subsequent to the second travel range, in which the flap is spaced farther away from the opening, than in the second travel range.

31. The exhaust gas turbocharger according to claim 29, wherein the opening and the flap provide free flow that increases to more of an extent over the travel in a third travel range subsequent to the second travel range, in which the flap is spaced farther away from the opening, than in the second travel range.

32. The exhaust gas turbocharger according to claim 30, wherein the opening and the flap provide free flow that increases linearly over a travel of the flap between the closed and a maximally open position in at least one travel range (s.sub.1, s.sub.2, s.sub.3).

33. The exhaust gas turbocharger according to claim 31, wherein the opening and the flap provide free flow that increases linearly over a travel of the flap between the closed and a maximally open position in at least one travel range (s.sub.1, s.sub.2, s.sub.3).

34. A motor vehicle, in particular passenger car, with an exhaust gas turbocharger according to claim 15.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements.

[0025] FIG. 1 is a waste gate valve of an exhaust gas turbocharger with a waste gate valve actuator according to an embodiment of the present invention in a cross section along an axial direction;

[0026] FIG. 2 is a waste gate valve of an exhaust gas turbocharger with a waste gate valve actuator according to another embodiment of the present invention in a depiction corresponding to FIG. 1;

[0027] FIG. 3 is a free-flowing surface or flow volume of the waste gate valve on FIGS. 1, 2 over a travel of the waste gate valve actuator; and

[0028] FIG. 4 is a waste gate valve of an exhaust gas turbocharger with a waste gate valve actuator according to another embodiment of the present invention in a depiction corresponding to FIGS. 1, 2.

DETAILED DESCRIPTION

[0029] The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background of the invention or the following detailed description.

[0030] FIG. 1 shows a waste gate valve of an exhaust gas turbocharger with a waste gas valve actuator according to an embodiment of the present invention in a cross section along an axial direction.

[0031] The waste gas valve actuator may have a flap with a base surface 1, which in a closed position depicted on FIG. 1 is supported tightly on an edge of an opening of a waste gate channel 2, and a channel-side elevation 3.

[0032] The base surface 1 and elevation 3 are rotationally symmetrical relative to an axial direction A denoted by a dash-dot line, which is perpendicular to the base surface 1 and, in the closed position, perpendicular to the opening of the waste gate channel 3.

[0033] The elevation 3 in the embodiment on FIG. 1 may have a first section adjoining the base surface 1 with a truncated contour and a second section with a truncated contour adjoining this first section and a front surface 3C of the elevation 3, wherein the second section exhibits a larger cone angle or is more obtuse.

[0034] Accordingly, an outer contour of the elevation 3 in the cross section on FIG. 1 may have a first section 3A along the axial direction A, and adjoining thereto a second section 3B facing away from the base surface, wherein the outer contour in the first section 3A may have outer tangents that coincide with the outer contour, which include a first angle a with the axial direction A of the latter that differs from zero, and in the second section may have outer tangents that coincide with the outer contour and are spaced apart from each other in the axial direction, which include a second angle β with the axial direction of the latter that differs from zero and the first angle α.

[0035] In the exemplary embodiment depicted in FIG. 1, the first section 3A extends over at least 20% of an overall height h of the elevation 3 in an axial direction A, and passes over in a radius (not depicted) into the base surface 1. In the exemplary embodiment, the second section 3B also extends over at least 20% of the overall height h, and passes over into the flat front surface 3C of the elevation 3 facing away from the base surface, whose diameter in the exemplary embodiment measures at most 75%, and at least 15%, of the diameter of the base surface 1.

[0036] In the exemplary embodiment on FIG. 1, the outer contour of the elevation 3 only exhibits a kink α.fwdarw.β between the base surface 1 and its front surface 3C, wherein its angle (α-β) measures no more than 45′.

[0037] In the exemplary embodiment on FIG. 1, the base surface 1 and elevation 3 are designed as a single piece with each other.

[0038] In the exemplary embodiment on FIG. 1, the flap is designed as a single piece with a carrier 4.

[0039] The flap can be pivoted between the closed position depicted on FIG. 1, in which its base surface 1 is supported on the edge of the opening of the waste gate channel 2, and a maximally open position, in which the base surface 1 is spaced maximally apart from the edge. To this end, the carrier 4 is pivoted to a turbocharger housing 5, as denoted on FIG. 1 by a tilt arrow s.

[0040] The opening and flap are designed in such a way that a free-flowing surface of the opening of the waste gate channel 2 and/or flow volume through the opening of the waste gate channel 2 increases to less of an extent over the travel s of the flap between the closed (s=0%) and maximally open position s=100%) in a first travel range s.sub.1 than in a second travel range s.sub.2 subsequent thereto, in which the flap is spaced farther away from the opening. To this end, FIG. 3 depicts a free-flowing surface or flow volume of the waste gas valve, which on FIG. 3 is marked Cd, over the travel s of the waste gate valve actuator. As evident, contouring the elevation 3 makes it possible to create a linear-concave progression for the free-flowing surface or flow volume over the travel s.

[0041] In a view corresponding to FIG. 1, FIG. 2 shows a waste gate valve of an exhaust gas turbocharger with a waste gate valve actuator according to another embodiment. Corresponding features are identified by identical reference numbers, so that reference will be made to the description above, and only differences will be covered below.

[0042] In the embodiment on FIG. 2, the elevation 3 rotationally symmetrical to the axial direction A exhibits a freeform contour. The outer contour is curved in a first section 3A and a second section 3B adjoining the latter, and exhibits no kinks between the base surface 1 and front surface 3C.

[0043] In the cross section on FIG. 2, the outer contour in the first section 3A may have at least one outer tangent T.sub.A denoted with a double dot-dashed line, which includes a first angle a with the axial direction A that differs from zero, and in the second section 3 exhibits at least two outer tangents T.sub.B denoted with a double dot-dashed line that are spaced apart from each other in an axial direction A (vertically on FIG. 2), which include a second angle β with the axial direction A of the latter that differs from zero and the first angle α.

[0044] To this end, a dashed line on FIG. 3 depicts the free-flowing surface or flow volume of the waste gate valve of FIG. 2 over the travel s of the waste gate valve actuator. As evident, contouring the elevation 3 makes it possible to create a linear-concave progression for the free-flowing surface or flow volume over the travel s. The free-flowing surface or flow volume over the travel s here increases to more of an extent in a third travel range s.sub.3 subsequent to the second travel range s.sub.2, in which the flap is spaced farther away from the opening, than in the second travel range s.sub.2.

[0045] In a view corresponding to FIG. 1, FIG. 4 depicts a waste gate valve of an exhaust gas turbocharger with a waste gate valve actuator according to another embodiment. Corresponding features are identified by identical reference numbers, so that reference will be made to the description above, and only differences will be covered below.

[0046] In the embodiment on FIG. 4, the elevation 3 is not rotationally symmetrical relative to the axial direction A, but rather is generated in the exemplary embodiment by three consecutive truncated cones, whose axes are inclined relative to the rotational axis D of the flap, and which are denoted by dashed lines on FIG. 4 for illustrative purposes.

[0047] Accordingly, the elevation 3 here exhibits a flat front surface 3C that faces away from the base surface, and is offset toward the rotational axis D of the flap (to the left on FIG. 4) in relation to a base surface-side floor surface 3D of the elevation 3, in which the elevation 3 passes over into the base surface 1 or adjoins the latter, wherein the non-rotationally symmetrical elevation 3 is inclined against the axial direction A toward the rotational axis D of the flap in sections, namely in the area of the two truncated cones facing away from the base surface.

[0048] While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims and their legal equivalents.