DE102008020732A1 - Charging device i.e. exhaust gas turbo charger, for motor vehicle, has fixing units movably supported/guided at shovel bearing ring, at bearing housing or at contour sleeve in radial direction - Google Patents

Abstract

The device (1) has a shovel bearing ring (2) with guide vanes (3) rotatably supported on the shovel bearing ring, and a contour sleeve (10) forming a part of a flow channel and surrounding a turbine and/or compressor wheel (9). The contour sleeve is held at a bearing housing (12) of the charging device via two fixation units (11), where the fixation units penetrate the shovel bearing ring in an axial direction. The fixing units are movably supported/guided at the shovel bearing ring, at the bearing housing or at the contour sleeve in a radial direction.

Description

The The present invention relates to a charging device, in particular an exhaust gas turbocharger for a motor vehicle, according to the The preamble of claim 1. The invention also relates a, equipped with such a charging device internal combustion engine and a, equipped with such an internal combustion engine Motor vehicle.

From the DE 10 2004 044 703 A1 a generic charging device is known which comprises a turbine housing, a bearing housing, a blade bearing ring and a contour sleeve, which forms a portion of a flow channel in a turbine of the exhaust gas turbocharger. In addition, the loading device on lightweight blades, which are arranged pivotably in a formed between the contour sleeve and the blade bearing ring annular channel. For fastening the blade bearing ring and the contour sleeve on the bearing housing, at least one expansion screw is provided, which engages through the contour sleeve and the blade bearing ring and into the bearing housing and has at least one predetermined section of an expansion shaft. As a result, in particular the high thermal expansions during operation of the charging device should be compensated.

As a general rule usually all components are subject to a Charging device during operation strong temperature fluctuations and thus different degrees of expansion. By different Materials as well as different geometries, is the amount of individual expansions, however, vary greatly, so this Components, if they are firmly connected, under large thermal stresses can stand, which is the most unfavorable Case for failure of the actual function or destruction of the component can lead. The contour sleeve is in addition to that, the smallest possible and homogeneous gap to represent a turbine wheel of the charging device, wherein the Gap must be so big that the tumbling movements of a runner, which is composed of the turbine wheel and a shaft, as well Manufacturing and assembly tolerances are possible without that there is a contact between the turbine wheel and the contour sleeve comes. To avoid the thermal stresses between the individual components and in particular the warranty a homogeneous gap between the contour sleeve and the Turbine wheel, to be able to guarantee, is an unobstructed Expansion of the contour sleeve required.

The The present invention addresses the problem of for a charging device of the generic type Art to provide an improved embodiment in which an unobstructed expansion of a contour sleeve due of temperature changes is easily possible.

This Problem is inventively by the objects of the independent claims. advantageous Embodiments are the subject of the dependent Claims.

The Invention is based on the general idea, a contour sleeve a charging device which usually has a turbine wheel circumferentially encloses, about at least two fasteners comprising a blade bearing ring penetrate the charging device in the axial direction, on a bearing housing attach the charging device, wherein the fasteners at least on the blade bearing ring, on the housing or on the Contour sleeve are movably mounted / guided in the radial direction. This means that the fasteners on the other components, For example, on the bearing housing or on the blade bearing ring in radial Direction are fixed, so that when the temperature increases, in which the contour sleeve is usually uniform expands in the radial direction, for example, fixed to the contour sleeve connected fasteners radially on the blade bearing ring or radially can adjust the bearing housing, so that the Temperature expansion no mechanical stresses and therefore no mechanical loads in, out of the contour sleeve and enters the cartridge bearing ring formed cartridge. Of course is also conceivable that the radial fixation of the fasteners takes place on the blade bearing ring, in which case the fasteners on the bearing housing and on the contour sleeve in radial Direction movably stored / guided. With the invention Connection technology, it is thus possible, all, usually occurring during the operating state of the charging device Temperature changes, preferably stress-free record to be able to, thereby reducing the mechanical load within the charger significantly lowered and thereby the life the charging device can be increased. The radial fixation the fastening elements can, for example, be done by fitting holes, while the possibility for radial adjustment The fastening elements, for example, by extending in the radial direction Slotted holes can be realized. Generally speaking with the solution according to the invention a decoupling an axial and a radial fixation of at least the contour sleeve possible from the bearing housing.

In general, it is also conceivable that the fastening elements are firmly connected to two components, that is, for example, both on the contour sleeve and the blade bearing ring and only on the remaining third component, in this example, the bearing housing, one degree of freedom in the radial direction. In this case, the contour sleeve and the blade bearing ring would be made of the same material or at least of materials with approximately the same coefficients of thermal expansion.

at an advantageous embodiment of the invention Solution, a total of three fasteners are in the Type of attachment pins provided, which along a circumference the contour sleeve with an intermediate angle of 120 ° are arranged. This number of fasteners On the one hand allows a reliable attachment the contour sleeve on the blade bearing ring or on the bearing housing and on the other hand offers a statically determined system. Such a thing statically determined system would be with a total of four fasteners not reachable, but with four fasteners the unobstructed thermal expansion easily possible would.

at a further advantageous embodiment of the invention Solution, the blade bearing ring has an outward pointing radial collar, over which he with at least low Axial play between an inward facing radial collar of a Turbine housing and a spacer is clamped, wherein the spacer on the one hand on the turbine housing and on the other hand supported on the bearing housing. These Variant differs from a comparable alternative, in which the blade bearing ring on the fasteners is connected to the bearing housing, characterized in that now the Shovel bearing ring itself here over his outwardly facing radial collar with respect to the bearing housing or with respect to the turbine housing in the axial direction is fixed. About one between the turbine housing on the one hand and the bearing housing on the other hand arranged Spacer sleeve, can be a precisely predefined permissible axial clearance of the vane bearing ring, so that also in this area temperature increases usually not to interfere with the operation of the charging device Temperature stresses are likely to lead.

Further important features and advantages of the invention will become apparent from the Subclaims, from the drawings and from the associated Description of the figures with reference to the drawings.

It it is understood that the above and the following yet to be explained features not only in each case specified combination, but also in other combinations or can be used in isolation, without the scope of the present To leave invention.

preferred Embodiments of the invention are in the drawings and will become more apparent in the following description explained, wherein the same reference numerals to the same or similar or functionally identical components relate.

there show, in each case schematically,

1 an exploded view of a charging device according to the invention in the region of a contour sleeve, a blade bearing ring and a bearing housing,

2 a representation like in 1 but from a different perspective and without a turbine wheel,

3 a view of a turbine wheel of a charging device according to the invention,

3a a sectional view along the sectional plane AA,

3b a sectional view along the section plane BB,

3c a sectional view along the section plane CC,

4 a sectional view through a charging device in the region of a vane bearing ring, which has an outwardly facing radial collar,

5 a conventional construction of a variable turbine geometry with adjustable guide vanes,

6 various views and sections through a variable turbine geometry according to the 5 .

7 Representations in the 6 However, in another embodiment of an axial guide of an adjusting ring of the variable turbine geometry.

According to the 1 , Has a charging device according to the invention 1 a variable turbine geometry, which is usually a blade bearing ring 2 , several vanes 3 , as well as an adjusting ring 4 (see. 5 ). The individual vanes 3 penetrate the blade bearing ring with a blade journal 2 in the axial direction, being on one of the vanes 3 opposite side of the blade bearing ring 2 vane levers 5 are connected to the respective blade pins. These shovel levers 5 have a radially outwardly directed lever head 6 on that in corresponding recesses 7 the adjusting ring 4 intervene (cf. 5 ). By turning the adjusting ring 4 around an axis 8th the charging device 1 , the individual vanes can 3 be adjusted. Even understandably, it may be in the example. In 1 shown variable turbine geometry also act to a compressor geometry. Radial inside the individual vanes 3 , is according to the 1 a turbine wheel 9 arranged, which also around the axis 8th rotatable in the charging device 1 is stored. Of course, this may again be a compressor wheel. Enclosing to the turbine / compressor wheel 9 is a contour sleeve 10 provided, which forms at least a part of a flow channel and which according to the 1 over three fasteners 11 on a bearing housing 12 the charging device 1 is held. The fasteners 11 are, for example, designed as cylindrical pins and penetrate the blade bearing ring 2 in the axial direction.

To thermal expansion, which during operation of the charger 1 Frequently occurring to be able to absorb, are the three fasteners 11 at least on the blade bearing ring 2 , on the bearing housing 12 or on the contour sleeve 10 In the radial direction adjustable stored / guided. In the representation according to the 2 , are the three fasteners 11 on the contour sleeve 10 by means of a fitting bore 13 fixed in the radial direction while in the blade bearing ring 2 and in the bearing housing 12 to the respective fitting bore 13 aligned and formed in the radial direction slots 14 are formed, so that at a temperature increase, which in the contour sleeve 10 due to its symmetrical shape leads to a radial expansion, which is fixed to the contour sleeve 10 connected fasteners 11 in the radial direction in the associated oblong holes 14 of the vane bearing ring 2 or the bearing housing 12 Adjust and thereby compensate for the thermal expansions easily. Of course, it should be noted that the fitting holes 13 also in the blade bearing ring 2 or in the bearing housing 12 may be provided, in which case the respective slots 14 in the contour sleeve 10 and the bearing housing 12 as well as in the contour sleeve 10 and in the vane bearing ring 2 must be provided to allow easy temperature expansion.

It is also conceivable that the fasteners 11 to two components, that is, for example, both on the contour sleeve 10 as well as on the vane bearing ring 2 are firmly connected and only to the remaining third component, in this example so on the bearing housing 12 , there is one degree of freedom in the radial direction. This would be the contour sleeve 10 and the blade bearing ring 2 preferably of the same material or at least of materials with approximately the same coefficients of thermal expansion.

Like that 1 and 2 it can be seen, are the three fasteners 11 Evenly distributed in the circumferential direction, that is, with an intermediate angle of 120 °, arranged to each other. Generally has the contour sleeve 10 the task, the smallest possible and homogeneous gap to the turbine wheel 9 However, the gap should be so large that a wobbling motion of a rotor, which is usually from the turbine wheel 9 and an associated shaft, and manufacturing tolerances are possible without causing a contact between the turbine wheel 9 and the contour sleeve 10 comes. In order to be able to minimize the manufacturing tolerances, it is for the contour sleeve 10 imperative that their position also directly from the bearing housing 12 is specified from.

According to the representations in the 1 to 3 , are the fasteners 11 formed waisted and are in the associated fitting holes 13 , here in the mating holes 13 the contour sleeve 10 , joined and firmly connected, for example by welding, riveting or the like. A minimum possible distance between the contour sleeve 10 on the one hand and the blade bearing ring 2 on the other hand, for example, by two frets 15 on the waisted fasteners 11 set, so that a clearance of the vanes 3 can be guaranteed without jamming. On the waisted fasteners 11 may also have washers 16 put on and with the fasteners 11 firmly connected. This is the contour sleeve 10 firmly with the blade bearing ring 2 connected, this assembly is commonly referred to as a so-called cartridge. The cartridge, that is called the contour sleeve 10 together with the vane bearing ring 2 , Is by means of fasteners in the bearing housing 12 inserted and through a turbine housing 17 (see. 4 ) axially against a heat shield 18 pressed. The turbine housing 17 is fixed to the bearing housing 12 connected.

Another type of axial positioning of the cartridge, that is, in particular of the blade bearing ring 2 , is according to the 4 shown, wherein the blade bearing ring 2 here an outward-pointing radial collar 19 possesses, over which he with at least a small axial play between an inwardly pointing radial collar 19 ' of the turbine housing 17 and a spacer 20 is trapped. The spacer 20 is supported according to the figure on the one hand on the turbine housing 17 and on the other hand, on the bearing housing 12 from. In an area where the bearing housing 12 directly on the turbine housing 17 is applied, in addition, a seal 21 be provided, which unfolds their sealing effect, if the bearing housing 12 against the turbine housing 17 , for example by means of a screw 22 , is biased.

With the inventive storage of the contour sleeve 10 , it is allowed to expand easily due to its direct hot gas contact, where it heats up quickly and strongly. Due to the arrangement of the slots 14 , According to the embodiments shown in the blade bearing ring 2 and in the bearing housing 12 , the central axis remains 8th the contour sleeve 10 relative to the axis of rotation 8th of the runner unchanged. This is particularly due to the fact that the fasteners 11 tangential in the oblong holes 14 issue. All degrees of freedom are due to the three tangential contacts and the axial attachment through the turbine housing 17 eliminated. For more than three fasteners 11 Although the system would be statically overdetermined, the basic mode of operation, that is, the unhindered thermal expansion, would nevertheless still exist. By this connection principle, it is also possible to different materials for contour sleeves 10 , Blade bearing rings 2 , Bearing housing 12 and fasteners 11 fall back, since the different thermal expansion coefficients now no longer affect the function of the contour sleeve 10 to have.

• – eine geringe Montagetoleranzkette, bei welcher ein Konturspalt zwischen dem Turbinenrad und der Konturhülse 10 reduziert werden kann, was zu einer Steigerung des Wirkungsgrads der Ladeeinrichtung 1 führt,
• – eine geringe Bauteilanzahl, was zu einer Reduktion der Kosten führt,
• – eine Eliminierung thermomechanischer Spannungen, wodurch eine Lebensdauer der einzelnen Bauteile steigt bzw. Werkstoffe mit geringerer Festigkeit verwendet werden können, welche üblicherweise darüber hinaus kostengünstiger sind,
• – eine einfache Bauteilgeometrie und eine einfache Montage,
• – eine einfache Übertragung auf andere Ladeeinrichtungen mit variablen Turbinen- und/oder Verdichtergeometrien.

Generally, the charging device according to the invention 1 following advantages:

• - A low mounting tolerance chain, in which a contour gap between the turbine wheel and the contour sleeve 10 can be reduced, resulting in an increase in the efficiency of the charging device 1 leads,
• A small number of components, which leads to a reduction of costs,
• Elimination of thermo-mechanical stresses, which increases the lifetime of the individual components or materials with lower strength can be used, which are usually also more cost-effective,
• - a simple component geometry and a simple assembly,
• A simple transfer to other charging devices with variable turbine and / or compressor geometries.

In general, while the fasteners 11 be executed one or more parts, which is always given that the blade bearing ring 2 assumes a predefined axial position, and so does the heat shield 18 can be relieved.

According to the 5 is again a variable turbine geometry with the individual components, in particular with the blade bearing ring 2 , the adjusting ring 4 and the associated vanes 3 shown. The individual vanes 3 are doing in holes in the blade bearing ring 2 inserted and on the opposite side with the associated blade levers 5 connected.

Then the adjusting ring 4 mounted so that the blade lever 5 in the corresponding recesses 7 on the adjusting ring 4 intervention. An adjusting unit, not shown, ensures in the fully assembled state for a rotation of the adjusting ring 4 and thus to an adjustment of the guide vanes 3 , For a safe engagement of the blade lever 5 and at least one for adjusting or rotating the adjusting ring 4 required adjustment lever 23 in the adjustment lever 4 can be ensured, the adjusting ring 4 always be led with at least a small game. The radial guidance of the adjusting ring 4 is usually realized by means of rollers, cylindrical pins, etc. Conceivable here is also a combination of radial guidance of the adjusting ring 4 on the inner diameter by cylindrical pins and axial guidance with the according to the 6 and 7 illustrated guide elements 24 ,

The respective sectional views along the sectional plane BB according to the 6 and 7 , show that between the adjusting ring 4 on the one hand and the guide elements 24 on the other hand, always an axial clearance s is present, so that the ease of movement of the adjustment 'can be guaranteed in itself. The size of the axial play s, can vary depending on the application. When using flat guide elements 24 , the game is affected by the height of the adjusting ring 4 and the bucket lever 5 given while using non-flat guide elements 23 , the game regardless of the adjusting ring 4 and the bucket levers 5 can be adjusted.

Generally, the offer according to the 6 and 7 shown guide elements 24 the big advantage that the adjusting ring 4 captive, that means, in particular, can be mounted in all positions, is held and that an axial and a radial guide are formed separately from each other. As a result, in particular a simpler and, above all, faster alignment during assembly of the preassembled variable turbine geometry in the charging device 1 possible, in which, moreover, less mounting aids are required. The guide elements offer 24 their simple component geometry an inexpensive axial guide element, wherein the guide elements 24 Conveniently designed as equal parts and beyond are universally applicable for various charging devices.

The guide elements 24 can either be directly on the adjusting ring 4 or on the blade levers 5 be attached and the axial guidance of the adjusting ring 4 take. The guide elements 24 can thereby one or both sides of the adjusting ring 4 be used, wherein when using multiple guide elements 24 also conceivable is that these together form a closed ring. The individual guide elements 24 or a ring formed from this can, for example, by welding, riveting, stapling or similar bonding method with the adjusting 4 or the blade levers 5 connected, it is also possible in general, the guide elements 24 from metallic or ceramic materials. Usually, the guide elements are 24 formed flat, which is also conceivable that they have at least a slight curvature.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• DE 102004044703 A1 [0002]

Claims (11)

Charging device ( 1 ), in particular an exhaust gas turbocharger for a motor vehicle, with - a variable turbine and / or compressor geometry, - a blade bearing ring ( 2 ) with rotatably mounted thereon guide vanes ( 3 ), - a, at least a portion of a flow channel forming, contour sleeve ( 10 ), which is a turbine or compressor wheel ( 9 ), wherein the contour sleeve ( 10 ) via at least two fastening elements ( 11 ), which the blade bearing ring ( 2 ) in the axial direction, on a bearing housing ( 12 ) of the charging device ( 1 ), characterized in that the at least two fastening elements ( 11 ) at least on the blade bearing ring ( 2 ), on the bearing housing ( 12 ) or on the contour sleeve ( 10 ) are movably mounted / guided in the radial direction. Charging device according to claim 1, characterized in that - three fastening elements ( 11 ) are provided with intervening 120 ° angle, or - that four fasteners ( 11 ) are provided with intervening 90 ° angle. Charging device according to claim 1 or 2, characterized in that the at least two fastening elements ( 11 ) on the vane bearing ring ( 2 ) are fixed in the radial direction, while on the bearing housing ( 12 ) and on the contour sleeve ( 10 ) Radially extending slots ( 14 ) are provided, which a radial displacement of the engaging therein fasteners ( 11 ) allow. Charging device according to claim 1 or 2, characterized in that the at least two fastening elements ( 11 ) on the bearing housing ( 12 ) are fixed in the radial direction, while at the blade bearing ring ( 2 ) and on the contour sleeve ( 10 ) Radially extending slots ( 14 ) are provided, which a radial displacement of the engaging therein fasteners ( 11 ) allow. Charging device according to claim 1 or 2, characterized in that the at least two fastening elements ( 11 ) on the contour sleeve ( 10 ) are fixed in the radial direction, while on the bearing housing ( 12 ) and on the blade bearing ring ( 2 ) Radially extending slots ( 14 ) are provided, which a radial displacement of the engaging therein fasteners ( 11 ) allow. Charging device according to claim 1 or 2, characterized in that exclusively on the bearing housing ( 12 ) Radially extending slots ( 14 ) are provided, which a radial displacement of the engaging therein fasteners ( 11 ) allow. Charging device according to one of claims 1 to 6, characterized in that at least one fastening element ( 11 ) is formed waisted. Charging device according to claim 7, characterized in that a waist region of at least one fastening element ( 11 ) an oval and an inner diameter of an associated fitting bore ( 13 ) has adapted cross-sectional shape. Charging device according to one of claims 1 to 8, characterized in that the blade bearing ring ( 2 ) an outwardly facing radial collar ( 19 ), over which he with at least slight axial play between an inwardly facing radial collar ( 19 ' ) of a turbine housing ( 17 ) and a spacer ( 20 ) is clamped, wherein the spacer ( 20 ) on the one hand on the turbine housing ( 17 ) and on the other hand on the bearing housing ( 12 ) is supported. Internal combustion engine with a charging device ( 1 ) according to one of claims 1 to 9. Motor vehicle with an internal combustion engine according to claim 10th