KR101244956B1 - Carrier ring of a conducting device with sealing air channel - Google Patents

Abstract

The sealing air channel 46, which is dug on the axial front face of the carrier ring 40, is sealed by the gas exhaust housing 22 on its open side. The sealing air channel can have a large cross section in the outer region of the cross section profile because of the arrangement, so that the whole sealing air can be supplied at only one point along the circumference.

Description

Carrier ring of guiding device with sealing air channel {CARRIER RING OF A CONDUCTING DEVICE WITH SEALING AIR CHANNEL}

The present invention relates to the field of guidance devices for turbomachines, in particular for turbines of exhaust gas turbochargers for turbocharged internal combustion engines.

The present invention relates to a carrier ring of a guide device with adjustable guide vanes, a guide device with such a carrier ring, and a turbomachine with such a guide device with such a carrier ring.

The exhaust gas turbocharger is used to improve the performance of an internal combustion engine (reciprocating piston internal combustion engine). The exhaust gas turbocharger consists of an exhaust gas turbine in the exhaust gas flow of the internal combustion engine and a compressor in the suction pipe of the internal combustion engine. The turbine wheel of the exhaust gas turbine is rotated by the exhaust gas flow of the internal combustion engine and drives the operating wheel of the compressor through the shaft. The compressor raises the pressure in the suction tube of the internal combustion engine, so that more air flows into the combustion chambers upon suction. Exhaust gas turbines are used as utility turbines. In this case, the utility turbines do not drive the compressor of the exhaust turbocharger through the shaft, but rather the generator, or drive other mechanical commercial components through the coupling.

The latest developments in today's reciprocating piston internal combustion engine sector seek to reduce emissions, reduce costs, and reduce fuel consumption. The supercharging system of the engine contributes decisively to the achievement of the development goals. In the past, for large engines, exhaust turbochargers with turbine and compressor components with fixed geometries were mostly used. This geometry is designed and tailored for each individual engine. But they could not be changed during engine operation. In the future, the use of adjustable (or variable) turbine geometry (VTG) during operation is further discussed to enable better adaptation of the exhaust turbocharger to the engine during operation. In this case, the openings of the guide vanes of the guide device of the exhaust gas turbine are changed through the twisting of the guide vanes. The use of adjustable turbine geometries is widespread in the known prior art, especially in the field of small engines (such as used in passenger cars). For large engines, for gas engines requiring precise control of the fuel / air ratio, variable turbine geometry is already in use today. In the future, it is believed that the use of variable turbine geometry will be expanded in large engines.

In an exhaust gas turbocharger with a variable turbine geometry, the guide device is designed to prevent the exhaust gas of the internal combustion engine from entering into the support positions of the guide vanes of the guide device, and to prevent the exhaust gas from leaking to the surroundings. Sealing air must be supplied.

In conventional guide devices, the sealing air is guided into an annular channel disposed inside the cross-sectional profile of the support housing of the guide device, hereinafter referred to as the support ring. Casting of the support ring requires a casting core due to this annular channel, which makes the casting process expensive. In addition, the cross section of the sealing air channel is relatively small due to the limited space ratio inside the profile of the support ring. Therefore, air must be supplied at multiple points in order to achieve a uniform supply of sealing air. For this purpose, other special tubes are required outside the guide device.

It is an object of the present invention to provide a carrier ring of a guiding device of a turbo machine, which can be manufactured cost-effectively.

This is according to the invention a circumferentially extending groove or groove which opens outwardly a sealing air channel for preventing the introduction of gas from the flow channel into the supporting positions of the guide vanes of the guiding device. It is achieved with a carrier ring formed as. In a carrier ring for an axially flowing guide device, the groove is dug on the axial front side of the carrier ring. In a radially perfused guide device, the grooves are dug on the lateral side lying radially outward or inward. If the sealing air channel is formed as an open groove in the carrier ring, the carrier ring can thereby be cast without a core for the sealing air channel.

The sealing air channel, which is dug on the axial front or side of the carrier ring, is sealed according to the invention by a gas exhaust housing and / or other housing part, for example a cover ring, on its open side.

The sealing air channel of the carrier ring formed according to the invention has a large cross section in the outer region of the cross section profile because of the arrangement, so that the whole sealing air can only be supplied at one point along the circumference. This allows for the omission of distribution tubes and requires less mechanical machining of the carrier ring.

Other advantages are described in the dependent claims.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 is an overall view of an exhaust gas turbocharger according to the prior art.
2 shows a cross section of an exhaust gas turbine with an adjustable guiding device axially flowing in accordance with the prior art;
3 shows a cross section of an exhaust gas turbine with an axially permeable adjustable guiding device with a carrier ring formed according to the invention.
4 is a view in the axial direction of a carrier ring formed according to the invention according to FIG. 3.
FIG. 5 shows a section taken along VV of the carrier ring according to FIG. 4.
6 shows a cross section of a carrier ring formed in accordance with the invention of a radially perfused guide device.

1 shows a conventional exhaust gas turbocharger with an exhaust gas turbine 20, a compressor 10, and a bearing housing 50 disposed therebetween. The exhaust gas turbine 20 comprises a gas inlet housing 21, through which the hot exhaust gas flows onto the turbine wheel before the exhaust gas is supplied to the exhaust apparatus through the gas exhaust housing 22. , To drive this. The turbine wheel is disposed at one end of the shaft rotatable about the axis A, which shaft is rotatably supported in the bearing housing 50. At the other end of the shaft is located a compressor wheel, the compressor wheel compresses the air sucked through the air inlet housing 11, and subsequently the air is collected in the air exhaust housing 12, the combustion of the internal combustion engine Supplied to the chambers. In the embodiment shown, the turbine is an axial flow turbine. Alternatively, the exhaust gas can be guided on the turbine wheel in a strictly radial direction, or in a direction slightly inclined in the radial direction, in which case it is called a radial flow turbine or a mixed flow turbine.

2 shows a section of an axial turbine of a conventional exhaust gas turbocharger. The turbine wheel 25 is disposed on the shaft 30 supported in the bearing housing 50 so as to be rotatable about the axis A. As shown in FIG. The turbine wheel 25 comprises a plurality of movable blades 26, which are arranged distributed along their circumference at the radially outer edge of the turbine wheel. The exhaust gas flow in the flow channel from the gas inlet housing 21 to the gas outlet housing 22 is indicated by arrows in the figures, respectively. The movable blades of the turbine wheel receive flow in the axial direction. Upstream of the movable blades 26 of the exhaust gas turbine, an adjustable guide device (adjustable turbine geometry) is arranged. This adjustable guide device comprises a plurality of guide vanes 41, each of which has a shank 42. Each guide vane 41 is installed in the housing so as to be rotatable about the axis B with its shank 42 respectively. The housing of the guiding device includes a carrier ring 40, which surrounds the flow channel in a ring shape. Carrier ring 40 may surround cover ring 45 towards the flow channel. The shanks 42 of the guide vanes 41 are arranged and supported in the carrier ring 40, ie in the bores provided therefor. These support positions-like the shanks 42 of the guide vanes 41-extend essentially in the radial direction. The carrier ring 40 is generally fixed to the gas outlet housing 22 and / or the gas inlet housing 21 by means of fastening means. Bolts, screws or joining plates are used as the fixing means. In addition, the adjustable guide device includes an adjustment ring 43 and an adjustment lever 44 per guide vane, which is guided towards the shank 42 through openings 49 in the carrier ring. In order to adjust the guide device, the adjustment ring 43 is moved in the circumferential direction. The adjusting lever 44 transmits the rotational movement to the shanks 42 of the guide vanes. A sealing air channel 46 is arranged in the carrier ring 40 to prevent the exhaust gas from entering into the support positions of the guide vanes 41 and also to prevent the exhaust gas from leaking to the surroundings. The sealing air is fed into the sealing air channel 46 extending in the ring-shaped interior of the profile of the carrier ring 40 at one or several points and flows into the flow channel through the openings for the shanks of the guide vanes.

In the axially flowing guide device with a carrier ring formed according to the invention according to FIG. 3, the openings 48 for receiving and supporting the shanks 42 of the guide vanes 41 are in this case also a sealing air channel. The sealing air is supplied through 46. The sealing air channel 46 is sealed with sealing elements 47 with respect to the opening 49 for passing the adjusting lever 44, so that sealing air cannot leak along the shank of the guide vanes in this direction. As can also be seen from the schematic drawings of the axially perturbing guide device according to FIGS. 4 and 5, the sealing air channel 46 is in accordance with the invention which is recessed in the axial front of the carrier ring 40. It is formed as a groove.

In the mounted state, the sealing air channel 46 is defined by the housing part 22 in contact with the axial front face. Therefore, in the mounted state, an annular hollow space is created for the sealing air channel 46 as a groove dug in the carrier ring 40. In order to enlarge the cross section of the sealing air channel, there may be a groove 23 open in the axial direction on the housing side. In this case, the sealing air channel is composed of a carrier ring side sealing air channel 46 and a housing side groove 23.

Contact surfaces between the carrier ring and the adjoining housing parts may be formed flat, obliquely or stepped in the area of the sealing air channel.

Optionally, the groove 23 which enlarges the sealing air channel on the housing side can extend into the area of the cover ring 45. Due to this, the cross section can be made larger.

Optionally, the sealing air channel may be sealed by a sealing element 47 disposed radially inside and / or outside of the sealing air channel. In this way, the sealing air supplied into the sealing air channel 46 using the overpressure can be prevented from leaking through the connection between the gas exhaust housing 22 and the carrier ring 40.

Optionally, the grooves forming the sealing air channel 46 may be dug in front of the carrier ring 40 facing the gas inlet housing 21.

Optionally, the grooves forming the sealing air channel in the carrier ring and / or in the adjoining housing may be formed as annular groove segments, ie divided into multiple sections along the circumference. Can be. Each sealing air channel segment can be individually supplied with sealing air from the outside.

6 shows a cross section of a carrier ring of a radially perfused guide device, for example used in a radial flow turbine or a mixed flow turbine. In this case, the sealing air channel 46 is formed according to the invention by grooves into the carrier ring, which open radially outwardly or radially inwardly. Therefore, this groove forming the sealing air channel 46 is dug on the side of the carrier ring 40. The confinement of the grooves towards the annular hollow space is carried out by a neighboring housing part, which in the case of an exhaust gas turbine is for example a gas inlet housing 21. In order to enlarge the sealing air channel 46 into the neighboring housing part, a peripheral groove 23 may be dug.

In the schematic views according to FIGS. 4, 5 and 6, the adjustment lever for adjusting the guide vanes is not shown.

The embodiments described in detail represent a guide device with a carrier ring formed according to the invention as an adjustable guide device for an exhaust gas turbine. However, all features must be valid for general applications in any turbomachine, in particular in compressors.

10: compressor
11: air inlet housing of the compressor
12: air exhaust housing of the compressor
20: exhaust gas turbine
21 gas inlet housing of the exhaust gas turbine
22 gas exhaust housing of the exhaust gas turbine
23 groove in the housing of the exhaust gas turbine
25: turbine wheel
26: movable blade of turbine wheel
30: shaft of exhaust gas turbocharger
40: carrier ring of the guide device
41: guide vane, adjustable
42: Shank of the Guide Vane
43: adjustment ring
44: adjustment lever
45: cover ring
46: sealing air channel in the carrier ring
47: sealing element
48: opening for receiving and supporting shank of guide vane
49: opening for passing the adjustment lever
50; Bearing housing to support shaft of exhaust turbocharger
A: shaft of exhaust turbocharger shaft
B: Shank of the guide vane shank

Claims (14)

As a carrier ring 40 of a guide device with adjustable guide vanes 41, the carrier ring surrounds the flow channel in a ring shape, and the carrier ring lifts the shanks 42 of the guide vanes disposed in the flow channel. A carrier ring of a guide device with adjustable guide vanes 41 comprising openings 48 for receiving and rotatably supporting, and a sealing air channel 46 for supplying sealing air into the guide device, 40, the sealing air channel 46 is circumferentially extending grooves outwardly, and are excavated on the outer surface of the carrier ring 40, which seals the shanks 42. The groove into the openings 48 for receiving and rotatably supporting, so that the sealing air is recessed in the carrier ring. Guide with adjustable guide vanes 41, characterized in that it flows into the flow channel through the openings 48 in the carrier ring 40 for receiving and rotatably supporting the shanks 42. Carrier ring 40 of the device. 2. A carrier ring according to claim 1, wherein the sealing air channel (46) is divided into a plurality of annular groove segments along the circumference. A guide device with adjustable guide vanes (41), wherein the guide vanes (41) each have a shank (42), the shank each having the carrier ring (1) according to any one of the preceding claims. And a guide device rotatably supported in said opening portion (48) of said head (40). 4. A axially flowing guide device with adjustable guide vanes (41) according to claim 3, wherein the sealing air channel (46) is a circumferentially extending groove opening in the axial direction of the carrier ring (40). An axially flowing guide device, which is dug in the axial front face. A radially perfused guide device with adjustable guide vanes (41) according to claim 3, wherein the sealing air channel (46) is a side surface of the carrier ring (40) as a circumferentially extending groove opening in a radial direction. A radially perfused guide device dug into the groove. A turbomachine comprising a housing (22) and a guiding device according to claim 4, wherein the carrier ring (40) is adapted to the sealing air channel such that the housing (22) defines the sealing air channel (46) in an axial direction. A turbomachine lying on the housing (22) of the turbomachine with the front face having (46). 7. The circumference of claim 6, wherein in the housing 22 in the region of the axial confinement of the sealing air channel 46, it is circumferentially opened toward the sealing air channel 46 in the carrier ring 40. Turbo machine with grooves 23 extending in a direction. A turbomachine comprising a housing (21) and a guiding device according to claim 5, wherein the carrier ring (40) comprises the sealing air channel such that the housing (21) defines the sealing air channel (46) in a radial direction. A turbomachine lying on said housing (21) of said turbomachine with said side having (46). 9. The circumferential direction according to claim 8, wherein in the housing (21) in the region of the radial confinement of the sealing air channel (46) is opened in the radial direction toward the sealing air channel (46) in the carrier ring (40). Turbo machine with grooves 23 extending into the grooves. A turbomachine comprising a housing (22) and a guiding device according to claim 3, wherein the transition region between the carrier ring (40) and the housing of the turbomachine (1) for sealing the sealing air channel (46) transition area) a turbo machine in which sealing elements 47 are arranged. An exhaust gas turbine comprising a guide device according to claim 3. Compressor comprising a guide device according to claim 3. An exhaust gas turbocharger comprising an exhaust gas turbine according to claim 11. An exhaust gas turbocharger comprising the compressor according to claim 12.

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