CHARGING DEVICE WITH A WASTEGATE VALVE DEVICE

Abstract

A charging device may include a turbine housing and a wastegate valve device. The wastegate valve device may include a flap, a spindle arm, a wastegate spindle, an axial stop, and a lever arm non-rotatably attached to the wastegate spindle. The wastegate spindle may be rotatably mounted in a bushing disposed on the turbine housing. A wastegate duct may be disposed in the turbine housing. The wastegate duct may have a duct aperture enclosed by a valve seat. The duct aperture, when in a closed state, may be closed by the flap of the wastegate valve device. A sealing face of the flap may be defined by a sequence of at least two conical peripheral surfaces arranged next to one another and each having a different inclination.

Claims

1. A charging device, comprising: a turbine housing; a wastegate valve device including a flap, a spindle arm, a wastegate spindle, an axial stop, and a lever arm non-rotatably attached to the wastegate spindle; the wastegate spindle rotatably mounted in a bushing disposed on the turbine housing; a wastegate duct disposed in the turbine housing, the wastegate duct having a duct aperture enclosed by a valve seat, the duct aperture, when in a closed state, closed by the flap of the wastegate valve device; and wherein a sealing face of the flap is defined by a sequence of at least two conical peripheral surfaces arranged next to one another and each having a different inclination.

2. The charging device in accordance with claim 1, wherein: the at least two conical peripheral surfaces includes a plurality of conical peripheral surfaces arranged next to one another; and an inclination of each of the plurality of conical peripheral surfaces, arranged in sequence, increases towards the wastegate spindle.

3. The charging device in accordance with claim 1, wherein two adjacent conical peripheral surfaces of the at least two conical peripheral surfaces merge continuously into one another.

4. The charging device in accordance with claim 1, wherein the at least two conical peripheral surfaces provide a convex geometric shaping of the sealing face of the flap.

5. The charging device in accordance with claim 1, wherein: the at least two conical peripheral surfaces each have a respective angle with respect to a lower side of the flap facing the duct aperture; and the respective angle is configured such that an edge between two adjacent peripheral surfaces of the at least two conical peripheral surfaces abuts against the valve seat of the duct aperture when in the closed state.

6. The charging device in accordance with claim 5, wherein the respective angle of at least one of the at least two conical peripheral surfaces is greater or smaller by a predetermined amount than a cone angle of a sealing face of the valve seat.

7. The charging device in accordance with claim 1, wherein the axial stop includes an inner stop formed by at least two studs projecting radially outwards from the wastegate spindle which are arranged spaced apart from one another along a circumferential direction of the wastegate spindle.

8. The charging device in accordance with claim 1, wherein the axial stop includes an outer stop defined by the lever arm.

9. The charging device in accordance with claim 1, wherein the at least two conical peripheral surfaces are disposed coaxially.

10. The charging device in accordance with claim 1, wherein the at least two conical peripheral surfaces are arranged directly axially adjacent to one another and contact one another to define a circumferentially extending edge.

11. The charging device in accordance with claim 1, wherein: the at least two conical peripheral surfaces include a plurality of coaxial conical peripheral surfaces arranged in sequence along a common central axis of the plurality of conical peripheral surfaces; and an inclination angle between a respective one of the plurality of conical peripheral surfaces and a plane perpendicular to the common central axis sequentially increases in a direction towards the wastegate spindle.

12. The charging device in accordance with claim 11, wherein: the plurality of conical peripheral surfaces includes an upper conical peripheral surface and a lower conical peripheral surface, the upper conical peripheral surface disposed axially closer to the wastegate spindle than the lower conical peripheral surface; the upper conical peripheral surface and the lower conical peripheral surface contact one another to define a circumferentially extending edge which abuts a conical surface of the valve seat when in the closed state; the conical surface of the valve seat is inclined by an inclination angle relative to a plane perpendicular to a central cone axis of the conical surface of the valve seat; the inclination angle of the upper conical peripheral surface is larger than the inclination angle of the conical surface of the valve seat; and the inclination angle of the lower conical peripheral surface is smaller than the inclination angle of the conical surface of the valve seat.

13. The charging device in accordance with claim 1, wherein the wastegate spindle has an inner end disposed within an interior of the turbine housing and an outer end disposed outside of the turbine housing.

14. The charging device in accordance with claim 1, wherein the wastegate spindle has two circumferential spindle bearing surfaces separated by a circumferentially extending groove.

15. The charging device in accordance with claim 1, wherein the flap has an upper side facing away from the wastegate duct and a lower side facing towards the wastegate duct, and wherein the sealing face of the flap is disposed between the lower side and the upper side.

16. The charging device in accordance with claim 1, wherein the charging device is an exhaust gas turbocharger for a motor vehicle.

17. The charging device in accordance with claim 7, wherein the at least two studs includes at least three studs disposed equidistant from one another in the circumferential direction.

18. A charging device, comprising: a turbine housing; a wastegate valve device including a flap, a spindle arm, a wastegate spindle, an axial stop, and a lever arm non-rotatably attached to the wastegate spindle; the wastegate spindle rotatably mounted in a bushing disposed on the turbine housing; a wastegate duct disposed in the turbine housing, the wastegate duct having a duct aperture enclosed by a valve seat, the duct aperture, when in a closed state, closed by the flap of the wastegate valve device; and wherein the flap has an upper surface facing away from the wastegate duct, a lower surface facing towards the wastegate duct, and a convex shaped sealing face disposed between the upper surface and the lower surface, the sealing face defined by a plurality of coaxial conical peripheral surfaces disposed axially one after another, the plurality of conical peripheral surfaces each having a different inclination angle relative to the lower surface of the flap.

19. The charging device in accordance with claim 17, wherein adjacent conical peripheral surfaces of the plurality of conical peripheral surfaces merge continuously into one another.

20. A charging device, comprising: a turbine housing including a wastegate duct having a duct aperture enclosed by a valve seat; a wastegate valve device including a flap, a wastegate spindle having an inner end disposed within an interior of the turbine housing and an outer end disposed outside of the turbine housing, a spindle arm extending between the flap and the inner end of the wastegate spindle, an axial stop limiting axial displacement of the flap relative to the valve seat, and a lever arm non-rotatably attached to the wastegate spindle; the wastegate spindle rotatably mounted in a bushing disposed on the turbine housing; wherein the duct aperture, when in a closed state, is closed by the flap of the wastegate valve device; and wherein a sealing face of the flap is defined by a sequence of at least two conical peripheral surfaces arranged next to one another and each having a different inclination.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Here, in schematic form in each case:

[0022] FIG. 1a shows in plan view an integrated design of wastegate valve, comprising a flap, a spindle arm and a spindle with radially extending studs,

[0023] FIG. 1b shows the same integrated design of wastegate valve in a side view,

[0024] FIG. 2 shows the wastegate valve from FIG. 1, mounted in the turbine housing,

[0025] FIG. 3 shows a detail of the multi-conical sealing face of the wastegate valve from FIG. 1,

[0026] FIG. 4 shows a detail of the multi-conical sealing face of the wastegate valve from FIG. 1, which abuts against a conical sealing face of the valve seat, and

[0027] FIG. 5 shows an illustration of the axially extending studs, as viewed in the direction of the spindle axis.

DETAILED DESCRIPTION

[0028] FIGS. 1a and 1b show an integrated design of a wastegate valve of a preferred embodiment of a wastegate valve device 1. The wastegate valve device 1 comprises a flap plate, which is also simply referred to as a flap 2, or a valve body, a spindle arm 3, which extends from the flap plate 2 to an inner end of an essentially cylindrically formed wastegate spindle 4, that is to say, in the installed state of the wastegate valve device 1, an end that projects into the interior of the turbine housing, and fixes these to one another, in particular connects them to one another in a non-rotatable manner, and an inner axial stop 9, which comprises studs 9.sup.I to 9.sup.IV extending radially from the essentially cylindrically formed spindle 4.

[0029] In addition to the inner end, the wastegate spindle 4 has an outer end 6, which in the installed state projects from the turbine housing, whereby at the outer end 6 a lever arm (not shown) is non-rotatably connected to the spindle 4, which lever arm transmits, by means of an adjusting rod (not shown) or kinematics, the forces of an actuating device, e.g. a control element or an actuator, onto the wastegate spindle 4 and thus onto the flap plate.

[0030] In a preferred form of embodiment, the wastegate spindle 4 can be formed by two spindle bearing surfaces 4.sup.I and 4.sup.II separated by a groove 4.sup.III, which form an inner bearing surface, facing the inner end of the spindle, and an outer bearing surface, facing the outer end 6 of the wastegate spindle 4.

[0031] The wastegate spindle 4 is mounted in an essentially cylindrical design of bushing 14 shown in FIG. 2, which can be rotated about its central axis 5 in a turbine housing 10 of the charging device.

[0032] A wastegate duct 11 is formed in the turbine housing 10, which has a duct aperture 20 surrounded by a valve seat, which duct aperture, in a closed state, is closed by the flap 2 of the wastegate valve device 1.

[0033] The flap 2 of the wastegate valve 1 has an upper side 7, facing away from the wastegate duct 11, and a lower side 8 facing towards the wastegate duct 11, as well as a sealing contour, or sealing face 12, arranged between the upper side 7 and the lower side 8.

[0034] In accordance with the invention, the sealing face 12, as shown in FIG. 3, is formed by a plurality of cones, axially spaced apart and aligned coaxially with one another. In particular, these several cones are arranged relative to one another and spaced apart from one another, and the radii of the cones are selected such that the conical peripheral surfaces 12.sup.I to 12.sup.IV merge continuously into one another, whereby the inclination of the conical peripheral surfaces 12.sup.I to 12.sup.IV, arranged in sequence, increases continuously in the axial direction, as viewed in the direction from the side 8 of the flap 2 facing the wastegate duct, that is to say, from the lower side 8 towards the upper side 7, such that the sealing face 12 of flap 2 describes a convex shape with respect to a valve seat 13 of the wastegate duct 11 that is also of conical design.

[0035] The inventive form of embodiment of a multi-conical sealing face 12 in FIG. 3 comprises the peripheral surfaces 12.sup.I, 12.sup.II, 12.sup.III and 12.sup.IV, which have angles 15.sup.I, 15.sup.II, 15.sup.III and 15.sup.IV respectively relative to the lower side 8. In accordance with the invention, these angles are selected such that the edge between the central peripheral surfaces 12.sup.II and 12.sup.III abuts against a valve seat 13 of the duct aperture of the wastegate duct 11, and the angles 15.sup.II and 15.sup.III are larger and smaller respectively by a certain amount than the cone angle of the sealing face of the valve seat 13, that is to say, for example, 35 and 55 for a cone angle of the sealing face of the valve seat 13 of 45.

[0036] FIG. 4 shows how the sealing face 12 of the flap 2 abuts against the conical design of valve seat 13. Here the outer peripheral surfaces 12.sup.I and 12.sup.IV can be inclined such that they have a positive effect on the outflow of the exhaust gas flowing out of the wastegate duct 11 from a duct aperture of the wastegate valve device 1, in that, for example, they set the clearance provided between the valve seat 13 and the sealing face 12 in accordance with the desired duct aperture characteristics.

[0037] FIG. 5 shows the studs 9.sup.I to 9.sup.IV extending radially from the wastegate spindle 4 as viewed in the direction of the central axis 5 of the wastegate spindle 4. In the inventive form of embodiment as shown, the studs 9.sup.I to 9.sup.IV are evenly spaced apart in the circumferential direction, whereby the angular range in the circumferential direction covered by the studs 9.sup.I to 9.sup.IV corresponds to approximately 180.

[0038] The invention concerns a charging device, in particular an exhaust gas turbocharger for a motor vehicle, with a wastegate valve device. Such a wastegate valve device has an inner axial stop, which is formed by studs extending radially outwards from the wastegate spindle, which limit any outward displacement of the spindle. In the present wastegate valve it is an essential feature of the invention that the sealing face of the flap plate is formed by a plurality of cones, axially spaced apart and aligned coaxially with one another. In particular, these several cones are arranged relative to one another and spaced apart from one another, and the radii of the cones are selected such that the conical peripheral surfaces merge continuously into one another, whereby the inclination of the conical peripheral surfaces, arranged in sequence, increases in the axial direction, that is to say, from the lower side of the flap towards the upper side of the flap, such that the sealing face of the flap describes a convex shape with respect to a valve seat of the wastegate duct that is also of conical design.