EP2288792A2

EP2288792A2 - Vane grille arrangement of an exhaust gas turbocharger, exhaust gas turbocharger, and method for producing a vane grille arrangement

Info

Publication number: EP2288792A2
Application number: EP09722558A
Authority: EP
Inventors: Ralf Böning; Dirk Frankenstein; Holger Fäth; Marc Hiller
Original assignee: Continental Automotive GmbH
Current assignee: Continental Automotive GmbH
Priority date: 2008-03-18
Filing date: 2009-03-11
Publication date: 2011-03-02
Also published as: WO2009115437A3; KR20100125427A; US20110014032A1; JP2011515608A; DE102008014680A1; BRPI0910301A2; WO2009115437A2; CN101978137A

Abstract

The invention relates to a vane grille arrangement of an exhaust gas turbocharger with variable turbine geometry, comprising at least one carrier ring formed from at least one sheet metal part and used to mount VTG guide vanes, the VTG guide vanes being rotatably mounted in recesses of a carrier ring. The invention also relates to an exhaust gas turbocharger with variable turbine geometry, and a method for producing a vane grille arrangement.

Description

description

Leitgitteranordnung an exhaust gas turbocharger, exhaust gas turbocharger and method for producing a Leitgitteranordnung

The present invention relates to a baffle arrangement of an exhaust gas turbocharger with variable turbine geometry. Moreover, the present invention relates to an exhaust gas turbocharger with variable turbine geometry and a method for producing such a guide grid arrangement for or in an exhaust gas turbocharger.

Turbochargers with variable turbine geometry (VTG) have proven to be advantageous in the past for increasing the performance and reducing the consumption of internal combustion engines. With the aid of the variable turbine geometry, the inlet cross section, under which the hot exhaust gases are directed to the turbine wheel of the exhaust gas turbocharger, can be varied. As a result of this measure, unlike an exhaust-gas turbocharger with a rigid, non-adjustable turbine geometry, the speed of the boost pressure build-up can be set as a function of engine speed and engine load. It can therefore be ensured in a turbocharger with variable turbine geometry at each engine operating point, a rapid boost pressure build-up. Disadvantages of an exhaust gas turbocharger with a rigid turbine geometry during charge pressure build-up, such as the turbo lag, greatly delayed charge pressure build-up at low engine speeds, can be effectively prevented or at least reduced by means of an exhaust gas turbocharger with variable turbine geometry.

With commercially available turbochargers with VTG, the variable turbine geometry is realized by means of an adjustable guide grille. Such a baffle consists of a ring of variable orientation vanes located in a narrow area, referred to as a vane space, between the exhaust gas supply passage of the turbine and the turbine rotor. In order to allow effective, low-loss steering of the exhaust gas flow, the blade space must not be formed substantially wider than the height of the guide vanes. On the other hand, the vane space must not be too tight, because then the vanes could jam in operation as a result of thermal component deformations.

The document EP 1 734 231 A1 describes a turbocharger with variable turbine geometry in which the adjustable guide grid, as described above, is formed by a ring of variable orientation vanes. Here, the adjustability of the guide vanes is realized by the rotatable mounting of the guide vanes in a carrier ring, which is also referred to as a blade bearing ring realized.

Figure 1 shows a known guide grid arrangement 1, as e.g. in EP 734 231 A1. The Leitgitteranordnung 1 consists of a blade bearing ring 2, in which a plurality of VTG Leitschaufein 3 are stored. The VTG Leitschaufein 3 are rotatably supported by means of integrally formed pivot pin 4 in recesses 5 of the blade bearing ring 2. The vane ring 2 has a thickness DO that is one to two times the height HO of the VTG vane 3.

Such a blade bearing ring is typically manufactured by a machining process. For machining a vane bearing ring turning operations, drilling operations and possibly also milling operations are required. In order to produce the blade bearing ring with the aid of machining production methods, specially provided machine tools must be provided, which makes the production of such blade bearing rings complex and expensive.

The document EP 1 394 364 B1 describes a blade bearing ring with an analogous construction to the blade bearing ring shown in FIG. Here, the production of a blade bearing ring is proposed by means of a casting process. In a production of the blade bearing ring as a casting model and mold, the provision of a suitable melting furnace and the required in a casting machining after-treatment are to be mentioned as significant cost factors. The production of a blade bearing ring as a casting is therefore associated with a considerable cost.

Against this background, it is an object of the present invention to provide an alternative, compared to commercially available solutions Leitgitteranordnung for storing the VTG Leitschaufein an exhaust gas turbocharger. In addition, it is a further object of the present invention to provide an exhaust gas turbocharger with such Leitgit- teranordnung and a method for producing such a Leitgitteranordnung.

According to the invention, at least one of these objects by a Leitgitteranordnung with the features of claim 1 and / or by a Leitgitteranordnung with the features of claim 3 and / or by an exhaust gas turbocharger with the features of claim 12 and / or by a method for producing a Leitgitteranordnung with the features of claim 13 solved.

Accordingly, a guide grid arrangement of an exhaust gas turbocharger with variable turbine geometry is provided, which has at least one carrier ring formed from at least one sheet metal part for supporting VTG guide vanes, wherein the VTG vanes are rotatably mounted in recesses of a carrier ring.

In addition, a guide grid arrangement of an exhaust gas turbocharger with variable turbine geometry is provided, which has at least one support ring, which is formed from at least one annular component, and which has VTG Leitschaufein, which are rotatably mounted in recesses of a support ring, wherein the annular or the Components each have an axial extent that is less than 75% of the height of the VTG Leitschaufein.

Furthermore, according to the invention, an exhaust-gas turbocharger is provided, which has a turbine-side section with a supply channel for supplying exhaust gas, in which a turbine rotor is rotatably mounted and in which a guide-grid arrangement according to the invention is provided.

In addition, a method for producing a Leitgitteranordnung invention is provided with the following steps: providing at least one sheet metal part, generating a carrier ring with recesses from the at least one sheet metal part, providing VTG guide vanes, inserting the VTG Leitschaufein in the recesses of a carrier ring.

The idea on which the present invention is based is to provide a guide grid arrangement with at least one support ring formed from at least one conventional sheet metal part for the rotatable mounting of the VTG guide runner, which is made thin compared to commercially available support rings. The use of carrier rings made of sheet metal, which are thin compared to customary solutions, ensures rapid and uniform heating of the carrier rings during operation. As a result, the risk of jamming of the VTG Leitschaufein in the blade space due to a thermally induced bending of the carrier ring is significantly reduced. In addition, material savings can be realized when using such carrier rings compared to commercially available, thicker carrier rings. These savings in expensive, highly heat-resistant material make it possible to manufacture the guide-grid arrangement at low cost compared to known solutions.

Another idea of the present invention is to provide an exhaust gas turbocharger with variable turbine geometry with a guide grid arrangement according to the invention. By installing a guide grid arrangement according to the invention in an exhaust gas turbocharger, the total production costs for an exhaust gas turbocharger can be lowered in comparison to commercially available exhaust gas turbochargers. Since the risk of jamming of the VTG guide vanes is reduced by using a guide-grid arrangement according to the invention, an exhaust-gas turbocharger with such a guide-grid arrangement is additionally distinguished by a higher level of operational reliability compared with commercially available exhaust-gas turbochargers.

Another idea of the present invention is to provide a method for producing a baffle arrangement according to the invention. Compared to conventional methods for producing a Leitgitteranordnung, the inventive method is characterized in that the carrier rings are made for storage of the VTG Leitschaufein of conventional sheet metal parts. As a result, material savings can be achieved in the production of the carrier rings in comparison to machining or production as a casting. Due to these savings on expensive, high-temperature-resistant material, the method according to the invention enables a cost-effective manufacture of a guide-grid arrangement according to the invention in comparison with conventional methods.

Advantageous embodiments and modifications of the invention are subject of the dependent claims and the description with reference to the drawings.

According to a preferred embodiment of the invention, the sheet metal parts used for the production of the carrier rings have a thickness which is less than 75% of the height of the VTG Leitschaufein. More preferably, the thickness of the sheet metal parts is less than 60% and more preferably less than 50% of the height of the VTG guide vanes. Such an embodiment of the carrier rings has the advantage that with decreasing thickness of the sheet metal parts used for the production of the carrier rings a more rapid and uniform heating of the carrier rings is ensured, and the risk of jamming the VTG Guide vanes in the vane space due to thermally induced bending of the carrier rings is increasingly reduced. Furthermore, with decreasing thickness of the sheet metal parts used for the production of the carrier rings, increasing material savings can be realized in the production of the carrier rings. This in turn results in decreasing production costs for the entire baffle arrangement.

In a typical embodiment of the invention, a Leitgitteranordnung is provided, the VTG Leitschaufein each have a blade portion and a molded thereon pivot pin. Such a structural design of the VTG guide vanes allows them to be rotatably supported in a simple manner in respective recesses of a carrier ring.

In a further preferred embodiment of the invention, a guide grid arrangement is provided, in which the sheet metal parts for producing the carrier rings and the recesses of the carrier rings are punched and / or genibbelt. This results in cost advantages in the manufacture of the carrier rings and in the production of the entire Leitgitteranordnung. Alternatively, the sheet metal parts for the preparation of the carrier rings and the recesses of the carrier rings, of course, with the help of one or more other, cheaper method such. B. with another shear cutting method, with a wedge cutting method (in this case, in particular with a Teißschneidverfahren) or be prepared with a cleavage method.

In a first, general embodiment of the invention, a guide grid arrangement is provided with a single support ring, in whose recesses the pivot pins of the guide vanes are rotatably mounted. By such a one-sided mounting of the VTG Leitschaufein a particularly simple and inexpensive construction of the Leitgitteranordnung is possible. In a further preferred embodiment of the invention, a guide grid arrangement is provided with at least two and in particular exactly two carrier rings, between which the VTG Leitschaufein are sandwiched and in their recesses, the pivot pins of the VTG Leitschaufein are rotatably mounted. Such a two-sided mounting of the VTG guide vanes has the advantage that, in spite of the very narrow carrier rings, a large support width for receiving forces on the VTG guide vanes is available.

In a further preferred embodiment of the invention, a guide grid arrangement is provided in which a carrier ring is formed in each case from a plurality of stapeiförmig superimposed sheet metal parts, so that the support ring has congruent superposed recesses in which the pivot pins of the VTG Leitschaufein are rotatably mounted. Such a constructive design of the carrier rings has the advantage that, even with a one-sided storage of the VTG guide vanes, a large support width for receiving forces on the VTG guide vanes is available.

According to a typical embodiment of the invention, a baffle arrangement is provided in which the recesses of a carrier ring are mounted at equal radial distances from the center of the carrier ring and uniformly in the circumferential direction on the carrier ring.

In a further preferred embodiment of the invention, a baffle arrangement is provided, which has an anti-rotation device, which ensures in the installed state of the baffle arrangement in the turbocharger that the baffle arrangement is secured against rotation in the turbine housing and / or in the bearing housing of the turbocharger. Such a rotation lock is required in order to support the forces applied to the VTG guide blade on the turbine housing and / or on the bearing housing of the turbocharger. Typically, such a rotation by a screw of a Carrier ring realized on the bearing and / or on the turbine housing. However, such an anti-rotation device can also be designed, for example, as a tongue and groove connection between the bearing or turbine housing and the inner or the outer edge of a carrier ring.

According to a particularly preferred embodiment of the invention, a guide grid arrangement is provided in which the inner and / or the outer edge of a carrier ring is formed circular. Such a constructive design of a carrier ring is advantageous since both the turbine rotor lying within a carrier ring and the housing parts located outside the carrier ring have circular contours. However, the inner and / or the outer edge of a carrier ring may of course also be designed to be polygonal or otherwise ring-shaped, for example for realizing an anti-twist device.

According to a further preferred embodiment of the invention, a method for producing a baffle arrangement is provided, in which the sheet metal parts from which the carrier rings are produced, are produced by a shear cutting process. The production of sheet metal parts with a shear cutting method has significant cost advantages over the machining or manufacturing as a casting. Such a shear cutting method may be, for example, a punching method or a nibbling method. Alternatively, the sheet metal parts for the preparation of the carrier rings and the recesses of the carrier rings, of course, with the help of one or more other, cheaper method such. B. with a further shear cutting method, with a wedge cutting method (in this case, in particular with a Teißschneidverfahren) or be prepared with a cleavage method.

The invention will be explained in more detail with reference to the exemplary embodiments indicated in the schematic figures of the drawing. It shows: Fig. 1 is a schematic sectional view of a known Leitgitteranordnung;

2A, 2B a schematic sectional view and a schematic plan view of a first, general embodiment of a guide grid arrangement according to the invention;

FIG. 3 is a schematic plan view of an exemplary embodiment of an inventive device. FIG

guide vane;

4 shows a schematic sectional view of a preferred embodiment of a guide grid arrangement according to the invention;

5 shows a schematic sectional view of a further preferred embodiment of a guide grid arrangement according to the invention;

6 shows an exemplary, isometric view of an exhaust-gas turbocharger with variable turbine geometry with a guide-grid arrangement according to the invention.

In all figures of the drawing, identical or functionally identical elements - unless otherwise stated - have been provided with the same reference numerals.

2A and 2B show a schematic sectional view and a schematic plan view of a first, general embodiment of a guide grid arrangement 10 according to the invention. The guide grid arrangement 10 comprises a carrier ring 11 and a plurality of VTG guide vanes 12, which are rotatably mounted in the carrier ring 11.

The carrier ring 11 is formed here from a single sheet metal part 18 and has an inner edge 14 and an outer Edge 15 up. In addition, the carrier ring 11 has a plurality of recesses 16 which, as shown by way of example in FIG. 2B, may be arranged at the same radial distances from the center of the carrier ring 11 and uniformly in the circumferential direction on the carrier ring 11. The carrier ring 11 and thus also the sheet metal part 18 have a thickness D.

The VTG Leitschaufein 12 have a height H and in addition to the VTG Leitschaufein molded pintle 13 on. For rotatably supporting the VTG Leitschaufein 12 in the

Blade bearing ring 11 are each formed thereon pivot pin 13 inserted into the recesses 16 of the support ring 11.

According to the invention, the thickness D of the sheet metal part 18 is less than 75%, more preferably less than 60%, of the height H of the VTG guide rail 12. Typically, the thickness of the sheet metal part 18 is between 3 mm and 6 mm.

By rotating the VTG guide vane 12 stored in the carrier ring 11, the flow area of the turbine can be optimally adjusted for each engine operating point. At low engine speeds or full engine load, the VTG guide vanes 12 are placed in a flat position to reduce the turbine flow area and allow for rapid boost buildup due to the faster flowing exhaust gases. On the other hand, if there is excess exhaust gas on the turbine, the VTG guide vanes 12 are brought into a steeper position in order to reduce the flow area of the turbine and to limit the boost pressure as a result of the more slowly flowing exhaust gases.

Due to the fact that the turbine of an exhaust gas turbocharger very high exhaust gas temperatures of z. B. is exposed to 1050 ⁰ C, typically high temperature resistant materials are used in the manufacture of the Leitgitteranordnung 10 of the invention. The guide grid arrangement 10 can therefore, for example, a high-temperature austenitic steel be made with high chromium and nickel content. To increase the strength, molybdenum, vanadium, tungsten, niobium, titanium or boron may additionally be added to the high-temperature austenitic steel. In addition, it is conceivable to manufacture the guide grid assembly 10 from a nickel-based alloy or any other material that is capable of withstanding the exhaust gas temperatures prevailing within the turbine-side section of the turbocharger.

FIG. 3 shows a schematic plan view of a further, exemplary embodiment of a guide grid arrangement 10 according to the invention. Again, a carrier ring 11 formed from a sheet metal part 18 is provided, in the recesses of which several VTG guide vanes 12 are rotatably mounted. As shown by way of example, the carrier ring 11 has a plurality of grooves 17 attached to the outer edge 15 of the carrier ring 11, with the aid of which a rotationally secure attachment of the guide grid arrangement 10 in the turbine housing and / or in the bearing housing of the turbocharger is made possible.

FIG. 4 shows a schematic sectional view of a preferred embodiment of a guide grid arrangement 10 according to the invention. In addition to the first carrier ring 11 formed from a sheet metal part 18, a second carrier ring 19 formed from a sheet metal part 18 is provided herein. The VTG Leitschaufein 12 are sandwiched between the two support rings 11 and 19, so that the VTG Leitschaufein 12 are rotatably supported by means of the molded thereon pivot pin 13 on both sides in the recesses 16 of the support rings 11 and 19.

5 shows a schematic sectional view of a further, preferred embodiment of a guide-grid arrangement 10 according to the invention. Herein, a single carrier ring 11 is provided, which is formed by three sheet-metal parts 18 stacked one above the other in a stack. The resulting carrier ring 11 has congruently superimposed recesses 16, in which the VTG Leitschaufein 12 are rotatably supported by means of the molded thereon pivot pin 13. FIG. 6 shows, by way of example, an isometric view of an exhaust-gas turbocharger 21 with a guide-grid arrangement 10 according to the invention. The exhaust-gas turbocharger 21 has a turbine-side section 22. The guide grid arrangement 10 according to the invention is arranged here within the turbine-side section 22 of the exhaust-gas turbocharger between a feed channel 23 for supplying exhaust gas and a rotatably mounted turbine rotor 24.

Although the present invention has been described above with reference to preferred embodiments, it is not limited thereto, but modifiable in many ways. Thus, the invention is not limited to the specific structure of the guide grid arrangement shown in the preceding figures. Rather, it is precisely this guide grid arrangement can be modified in any manner, without departing from the basic principle of the invention.

In particular, the guide grid arrangement does not necessarily have to be formed, as shown in the figures, with only one or two carrier rings, but of course may also have three or more carrier rings. It goes without saying that a single carrier ring can be formed not only from one or three sheet metal parts but from any number of stapeiförmig arranged sheet metal parts, depending on what requirements are placed on the support ring in terms of its thermo-mechanical behavior and its mechanical resilience.

The pivot pins of the VTG guide vanes do not necessarily have to be integrally formed integrally with the VTG guide vanes. A single VTG vane can therefore also be formed by a separate pivot pin and a blade part, wherein the two components are rotatably connected to each other in a suitable manner. For such a compound of pintle and blade part offers, for example, a Keyway, a taper pin connection, a screw connection, a welded joint, a solder joint or any other compound which is adapted to ensure a reliable, rotationally fixed connection of pivot pin and blade part at the prevailing within the turbine side portion of the turbocharger high temperatures.

The inner and outer edges of a carrier ring need not necessarily be circular. The inner and / or the outer edge of the support ring may rather - for example, to realize an anti-rotation - also be polygonal or otherwise annular.

It goes without saying that the recesses for supporting the VTG guide vanes need not be arranged at equal distances from the center of the carrier ring and uniformly in the circumferential direction on the carrier ring. Rather, the recesses for supporting the VTG Leitschaufein can be arranged in any manner on a support ring, as long as taking into account the installation conditions in the turbine-side section of the turbocharger results in a technically viable Leitgitteranordnung.

Claims

claims

1. baffle arrangement (10) of an exhaust-gas turbocharger (21) with variable turbine geometry,

with at least one support ring (11, 19) formed from at least one sheet metal part (18) for supporting VTG guide vanes (12),

wherein the VTG Leitschaufein (12) are rotatably mounted in recesses (16) of a carrier ring (11, 19).

2. A grille assembly (10) according to claim 1, characterized in that the sheet metal parts (18) have a thickness (D) less than 75%, preferably less than 60% and more preferably less than 50% of the height (H) of the VTG guide vane is.

3. Leitgitteranordnung (10) of an exhaust gas turbocharger (21) with variable turbine geometry,

with at least one carrier ring (11, 19) which is formed from at least one annular component (18),

with VTG Leitschaufein (12) which are rotatably mounted in recesses (16) of a carrier ring (11, 19),

wherein the one or more annular members (18) each have an axial extent (D) that is less than 75% of the height (H) of the VTG guide leg.

4. baffle arrangement according to at least one of the preceding claims, characterized in that a VTG guide vane (12) consists of a blade part and at least one (integrally) integrally formed thereon pivot pin (13).

5. baffle arrangement according to at least one of the preceding claims, characterized in that the sheet metal parts (18) and / or the recesses (16) are punched and / or genibbelt.

6. baffle arrangement according to at least one of the preceding claims, characterized in that a single support ring (11) is provided, in whose

Recesses (16) the VTG Leitschaufein (12) are rotatably mounted.

7. Leitgitteranordnung according to at least one of claims 1 to 5, characterized in that two carrier rings (11, 19) are provided, between which the VTG Leitschaufein (12) are sandwiched and in whose recesses (16) the VTG Leitschaufein (16) 12) are rotatably mounted.

8. baffle arrangement according to at least one of the preceding claims, characterized in that a carrier ring (11, 19) of a plurality of sheet metal parts (18) is formed, which are stacked arranged one above the other, so that the support ring (11, 19) congruent superimposed recesses ( 16) in which the VTG Leitschaufein (12) are rotatably mounted.

9. baffle arrangement according to at least one of the preceding claims, characterized in that the recesses (16) of a carrier ring (11, 19) at equal radial distances from the center of the carrier ring (11, 19) and uniformly in the circumferential direction on the support ring (11, 19 ) are arranged.

10. Leitgitteranordnung according to at least one of the preceding claims, dadur ch ge kenn zeze t that the Leitgitteranordnung (10) has a rotation (17), which ensures in the installed state of the Leitgitteranordnung (10) in the exhaust gas turbocharger (21) with variable turbine geometry, the guide-grid arrangement (10) is secured against rotation in a turbine-side section (22) of the exhaust-gas turbocharger (21).

11. baffle arrangement (10) according to at least one of the preceding claims, characterized ge ch d e sure ch t that the inner edge (14) and / or the outer edge (15) of a carrier ring (11, 19) is circular.

12. An exhaust gas turbocharger (21) with variable turbine geometry, with a turbine-side portion (22) having a supply channel (23) for supplying exhaust gas, in which a turbine rotor (24) is rotatably mounted and in which a Leitgitteranordnung (10) according to at least one of the preceding claims is provided.

13. A method for producing a baffle arrangement (10) for an exhaust gas turbocharger (21) with variable turbine geometry, in particular a baffle arrangement (10) according to one of claims 1 to 11, with the steps:

(a) providing at least one sheet metal part (18),

(b) producing a carrier ring (11, 19) with recesses (16) from the at least one sheet metal part (18),

(c) providing VTG guide legs (12),

(D) inserting the VTG Leitschaufein (12) in the recesses (16) of a carrier ring (11, 19).

14. A method for producing a baffle arrangement according to claim 13, characterized in that the carrier ring (11) forming sheet metal parts (18) and / or the recesses (16) are produced by a shear cutting process.

15. A method for producing a baffle arrangement according to claim 14, characterized in that the carrier ring (11) forming sheet metal parts (18) and / or the recesses (16) are produced by a punching process and / or a Nibbelverfahren.