Guide vane ring element for a turbomachine

Abstract

The present invention relates to a guide vane ring element for a turbomachine, such as a gas turbine, with at least one drilled hole for the at least partial uptake of a flange of a rotatable guide vane, wherein an edge of the drilled hole on the vane element side is designed convexly along the edge in a first circumferential portion and, in particular, has a radius.

Claims

1. A guide vane ring element for a turbomachine, comprising: a vane ring element defining at least one drilled hole therein; the at least one drilled hole being configured for the at least partial uptake of a flange of a rotatable guide vane, wherein an edge of the at least one drilled hole on the vane ring element side is designed convexly in a first circumferential portion along the edge, wherein the convexly designed first circumferential portion has an edge that is curved towards the rotatable guide vane, wherein the first circumferential portion is configured and arranged to reduce any leakage between the vane element and the rotatable guide vane, and the rotatable guide vane is partially shaped such that it corresponds to a shape of the first circumferential portion, wherein a radius of the convexly designed first circumferential portion is at least 1% and/or at most 50% of a radius and/or a radial depth of the drilled hole, wherein the radius varies along the edge in the first circumferential portion, and wherein the radius increases along the edge in a first subregion of the first circumferential portion and decreases in an adjoining, shorter, second subregion of the first circumferential portion.

2. The guide vane ring element according to claim 1, wherein the edge has a constant radius along the edge in a second circumferential portion.

3. The guide vane ring element according to claim 2, wherein a maximum radius of the second circumferential portion is smaller than a radius, a maximum or a minimum, of the first circumferential portion.

4. The guide vane ring element according to claim 1, wherein the edge is processed by milling at least in the first circumferential portion, by means of a form milling cutter.

5. The guide vane ring element according to claim 1, wherein the convex edge is formed by a ruled surface.

6. The guide vane ring element according to claim 1, wherein the rotatable guide vane is configured as a guide vane cascade element, wherein the flange of the rotatable guide vane is mounted rotatably at least in part in one of the at least one drilled hole.

7. The guide vane ring element according to claim 6, wherein a face end of the rotatable guide vane on the drilled hole side lies radially opposite the first circumferential portion, substantially in the middle thereof, in a neutral position of the rotatable guide vane.

8. The guide vane ring element according to claim 1, wherein the element is configured and arranged in a turbomachine.

9. The guide vane ring element according to claim 1, wherein the first circumferential portion extends over a portion of the edge in the range of 2%-50%, and wherein a second circumferential portion extends over a remaining portion of the edge.

Description

BRIEF DESCRIPTION OF THE DRAWING FIGURES

(1) Other advantageous enhancements of the present invention ensue from the dependent claims and the following description of preferred embodiments. Shown partially schematically for this purpose are:

(2) FIG. 1, a perspective view of a portion of a guide vane ring element of a turbomachine according to an embodiment of the present invention;

(3) FIG. 2, a cut through the guide vane ring element with a guide vane along an axis of rotation of the guide vane in a neutral position of the guide vane; and

(4) FIG. 3, a cut, corresponding to FIG. 2, during manufacture of the guide vane ring element according to an embodiment of the present invention.

DESCRIPTION OF THE INVENTION

(5) FIG. 1 shows a perspective view of a portion of a radially inner guide vane ring element 10 of a turbomachine according to an embodiment of the present invention. FIG. 2 shows a cut through the guide vane ring element with a guide vane 20 along an axis of rotation of the guide vane (vertically in FIG. 2) in a neutral position of the guide vane.

(6) The guide vane has a flange 21, which is mounted rotatably in a drilled hole 30 of the guide vane ring element.

(7) The drilled hole 30 has an edge on the vane element side, in which it merges into an outer surface 11 of the guide vane ring element on the vane element side. This edge is composed of a first circumferential portion (31A, 31B) and a second circumferential portion 32.

(8) In the neutral or intermediate position of the adjustable guide vane 20 shown in FIG. 2, a face of a vane element of the guide vane lies, on its drilled hole side (in FIG. 2, bottom), radially opposite the middle of the first circumferential portion 31A, 31B in the peripheral direction of the edge.

(9) The edge has a radius R in the first circumferential portion 31A, 31B, which can be seen, in particular, in the cut of FIG. 2.

(10) In the exemplary embodiment, the radius increases in a first subregion 31A of the first circumferential portion along the edge and decreases in an adjoining shorter second subregion 31B of the first circumferential portion along the edge, with the first and second subregions together forming the first circumferential portion 31A, 31B.

(11) In a modification, which appears identically in the cut of FIG. 2, the radius R is constant in the first circumferential portion 31A, 31B.

(12) In the exemplary embodiment, the edge has a constant radius in the second circumferential portion 32 along the edge, which is markedly smaller than a maximum radius in the first circumferential portion 31A, 31B and can therefore not be seen in the schematic cut of FIG. 2. In a modification, the second circumferential portion can also have a sharp or blunt edge or a bevel.

(13) The first circumferential portion 31A, 31B is manufactured by milling using a form milling cutter 40, which is illustrated in FIG. 3.

(14) Although exemplary embodiments were described in the above description, it is noted that a large number of modifications are possible.

(15) In particular, in the exemplary embodiment, the guide vane 20 has an extension or skirt in the form a cylinder on the side of the flange 21 (and thus at the bottom in FIG. 2) lying radially opposite the vane element. In a modification that is not illustrated, the guide vane 20 can also terminate with the flange 21 in the radial direction or ends in it.

(16) The drilled hole 30 in the exemplary embodiment is a through-hole, which has a skirt in the radial direction, on which the flange 21 rests radially. In a modification that is not illustrated, the drilled hole 30 can also be a blind hole.

(17) Both modifications can be combined, so that the flange on the face side then rests radially on the bottom of the blind hole.

(18) Moreover, it is noted that the exemplary embodiments are merely examples, which are not intended to limit the scope of protection, the applications, and the design in any way. The person skilled in the art will instead be afforded a guideline by the above description for the implementation of at least one exemplary embodiment, with it being possible to make diverse changes, in particular with respect to the function and arrangement of the described components, without departing from the protective scope as ensues from the claims and combinations of features equivalent to them.