WO2019084107A1

WO2019084107A1 - Connecting device with protective shield, corresponding apparatus and charging device

Info

Publication number: WO2019084107A1
Application number: PCT/US2018/057261
Authority: WO
Inventors: Clement Kiefer
Original assignee: Borgwarner Inc.
Priority date: 2017-10-25
Filing date: 2018-10-24
Publication date: 2019-05-02

Abstract

The present invention refers to a device for connecting a turbine housing to a bearing housing of a turbocharger as well as to a turbocharger comprising such a device. The device 1 for connecting a turbine housing 40 to a bearing housing 50 of a turbocharger 100 comprises a clamping device 10. The clamping device 10 is adapted to connect a turbine housing flange 42 of the turbine housing 40 to a bearing housing flange 52 of the bearing housing. The device 1 further comprises a protective shield 30 which is arranged on the clamping device 10.

Description

CONNECTING DEVICE WITH PROTECTIVE SHIELD, CORRESPONDING

APPARATUS AND CHARGING DEVICE

Technical area The present invention relates to a device for connecting a turbine housing with a bearing housing for a turbocharger, as well as a charger device with a corresponding device.

Background More and more vehicles of the newer generation are being equipped with charging devices. To meet the performance targets and regulatory requirements, there is a need for advancing development throughout the powertrain and optimizing the individual components as well as the system as a whole for reliability and efficiency. Known turbochargers have a turbine housing, a compressor housing and a bearing housing, which is connected on the turbine side with the turbine housing and on the compressor side with the compressor housing. On the turbine side, in existing turbochargers, conventionally a turbine flange of the turbine housing is connected with a bearing flange of the bearing housing via a clamp or otherwise. The bearing housing supports a shaft, which carries the turbine wheel and the compressor wheel. During operation, the turbine wheel is driven by the exhaust gas flow. The compressor wheel is then rotated simultaneously via the shaft so that the compressor wheel can compress the intake air.

Due to the hot exhaust gas flow in the turbine, there is a strong heating of the turbine housing. Other components of the turbocharger, in particular the bearing housing, are heated by heat transfer from the turbine housing. Especially in the contact area between two turbocharger components, for example, in the contact area between the turbine flange and bearing flange, there is a strong heat conduction in particular due to the clamping. For this reason, existing concepts often involve heat barriers, which are arranged radially inside the flange contact area between the turbine housing and the bearing housing and, if necessary, jammed by the clamp between the two housing parts.

In case of extreme loads or unpredictable defects (e.g., material defects) there is a risk of a bursting of the turbine wheel. To protect users from physical damage and the surrounding components from being destroyed by the flying parts of the turbine wheel in the case of bursting, appropriate safety measures must be taken. It is known manner for the turbine housing to be formed for burst containment, wherein safety is guaranteed by an appropriate choice of material and material thickness for the turbine housing. Thus, developers are limited to certain materials. In addition, the necessary material thickness leads to an increased weight of the turbine housing.

An object of the present invention is to reduce the heat transfer from the turbine to other turbocharger components. Another object is to provide a burst protection for the turbine.

Summary of the invention

The present invention relates to a device for connecting a turbine housing with a bearing housing for a turbocharger, as well as a charger device with a corresponding device.

The inventive device for connecting a turbine housing with a bearing housing for a turbocharger comprises, in a first embodiment, a clamping device for connecting a turbine housing flange with a bearing housing flange. Furthermore, the device has a protective shield, which is arranged on the clamping device.

Since the clamping device is located between the turbine housing and bearing housing and since the protective shield is arranged on the clamping means, in the installed state heat transfer can be reduced by the protective shield, in particular heat radiation from the turbine housing to the bearing housing. The shield thus has the function of a heat shield. Also, a heat transfer to other turbocharger components arranged on the bearing housing side past the protective shield can be reduced. As a result, in turn, heating of the turbocharger components, in particular of the bearing housing and of the compressor housing, can be contained. This can lead to a larger operating range of the turbocharger and increase the life of the turbocharger components.

At the same time, the shield can also serve as burst protection. The shield can for example be designed such that, in the event of bursting of the turbine wheel and a possible associated destruction of the turbine housing, it intercepts flying parts. Therewith destruction of adjacent components and possibly bodily injury to a user can be avoided. In addition, this safety measure allows the developers greater freedom in the design of the turbine housing and in the choice of materials for the turbine housing. For example, the material thickness (wall thickness) can be kept lower, as a failure of the turbine housing is protected by the shield. Consequently, material can be saved and the turbine housing can be made lighter.

In embodiments that can be combined with the preceding embodiment, the clamping device can be ring-shaped. Further, the protective shield can be annular.

These advantageous embodiments allow a simple attachment of the clamping device to the two flanges, as they are normally designed to be round. Furthermore, a ring-shaped clamping device provides, by its outer peripheral surface, an advantageous attachment possibility for a protective shield. For example, an arrangement of the protective shield directly on a part of the turbine housing or the bearing housing or, in a possibly more complex form of the shield, or with the help of an additional fastener, is possible which serves for example as an adapter between the housing and protective shield. A ring-shaped configuration of the clamping device and/or the protective shield can generally be manufactured with less effort than, for example, a shape adapted to discontinuous contours of the housing. Furthermore, the annular design of the protective shield can be an ideal shield for the round turbine housing.

In embodiments that can be combined with any of the preceding embodiments, the protective shield can be disposed, going outwards from the rotational axis of the turbocharger, radially outside the clamping device. In embodiments that can be combined with any of the preceding embodiments, the protective shield may be arranged coaxially to the clamping device.

In embodiments that can be combined with any of the preceding embodiments, the protective shield can coaxially surround at least a part of a clamping device circumference. In other words, this means that the protective shield surrounds a part of the periphery of the clamping device, for example half, wherein the other half of the circumference is not surrounded by the protective shield. In embodiments that can be combined with any of the preceding embodiments, the protective shield may be arranged on an outer surface of the clamping device, whose normal vector is oriented outwards in the radial direction on an outer surface of the clamping device.

In embodiments that can be combined with any of the preceding embodiments, the protective shield may be connected to the clamping device by a form-locking, force-fitting or materially bonding connection. In particular, the protective shield can be connected to the clamping device by a welded connection.

In embodiments that can be combined with any of the preceding embodiments, the protective shield can be manufactured integral with the clamping device.

In embodiments which can be combined with any of the preceding embodiments, the protective shield can have a cross-sectional profile extending from the clamping device in the radial direction, preferably in the radial and axial direction.

In embodiments that can be combined with any of the preceding embodiments, the protective shield having a bent cross-sectional profile. Further, the protective shield can comprise a substantially C-shaped cross-sectional profile. Here the cross-sectional profile can have a concave surface which in the installed state faces the turbine housing in the axial direction. Such advantageous embodiments can lead to a better heat shield. By having the concave surface of the protective shield face the turbine housing, a larger heat radiation area can be covered than with a protective shield with a straight cross-sectional profile and comparable radial orientation. In other words, these configurations lead to more efficient heat shield with the same small radial projection compared to a protective shield of non- curved cross-sectional profile.

In embodiments that can be combined with any of the preceding embodiments, the shape and strength of the shield may be configured such that the shield can additionally serve as a burst protection. The protective shield can be configured, for example, so that it extends in the axial direction over at least a third of the turbine housing. Preferably the shield can extend over at least half the turbine housing. Thus, the shield advantageously simultaneously fulfills the function of a heat shield and a burst protection. In embodiments that can be combined with any of the preceding embodiments, the shield can be configured at least partially multi-layered, in particular two or three layers. One or more cavities can be formed between the layers of the shield. In particular, the cavity or cavities can be at least partially filled with an insulating material.

In embodiments that can be combined with any of the preceding embodiments, can the shield 30 can be a sheet metal part, a metal injection molded part (MEVI part), or be made as a precision cast part.

In embodiments that can be combined with any of the preceding embodiments, the protective shield can exhibit one or more reinforcing beads and/or stiffening ribs.

In embodiments that can be combined with any of the preceding embodiments, the clamping means can comprise a first clamp segment and a second clamp segment. Further, the protective shield can comprise a first shield segment and a second shield segment. Further, when the clamping means and the protective shield have in each case two sections, the first shield segment can be arranged on the first clamp segment and the second shield segment on the second clamp segment. The two-part design ensures easy assembly and/or disassembly of the clamping device on the bearing flange and turbine flange. Since the protective shield is also configured in two parts and each shield segment of may be disposed on one clamp segment, the protective shield can also be mounted and/or disassembled in a simple manner together with the clamping device. If the protective shield is releasably attached to the clamping device, one shield segment, or both may also be mounted to the clamping device or dismantled independently of the clamping device. This results in a flexible adaptation of the device to different protection requirements because the shield can be removed or can be replaced by another protective shield.

In embodiments in which the clamping means comprises a first clamp segment and a second clamp segment, the first clamp segment and said second clamp segment may be configured connected to each other, in particular screwed.

In embodiments that can be combined with any of the preceding embodiments, the clamping means may be arranged to be tensioned in the circumferential direction by drawing together. Furthermore, the clamping device may comprise at least one tensioning device. The tensioning device can be adapted to tighten the clamping means in the circumferential direction by pulling or drawing together. In embodiments that can be combined with any of the preceding embodiments, the clamping means can be a stretchable circumferentially by tensioning. In particular, in the latter case, the clamping device can have surfaces oriented radially inwardly which are engageable with radially outward oriented surfaces of the flanges. In this way, the turbine housing and the bearing housing can be clamped to each other in the axial direction.

In embodiments that can be combined with any of the preceding embodiments, the clamping means can be a band clamp.

The invention further comprises a charging device, in particular an exhaust gas turbocharger. The charging device comprises a turbine housing, a compressor housing, a bearing housing and a device according to any one of the preceding embodiments. The turbine housing and the bearing housing are connected by the device.

Brief description of the figures

Fig. l shows an isometric view of the device according to a first embodiment of the invention for connecting a turbine housing with a bearing housing;

Fig. 2a shows a front view of the device according to the invention from Fig. 1 in a radial plane.

Fig. 2b shows a sectional view of the device according to the invention of Fig. 2a. in an axial plane;

Fig. 3 shows an enlarged partial section of a segment in an axial plane of the

inventive device according to of Fig. 1 in the installed state with a turbine housing and a bearing housing;

Fig. 4 shows a partial section of a side view of the charging device according to the invention;

Fig. 5 shows an enlarged partial section of a sectional view of an axial plane of the inventive device in the installed state according to a second embodiment; Fig. 6 shows an enlarged partial section of a sectional view of an axial plane of the device according to the invention in the installed state according to a third embodiment.

Detailed description

In the following, with reference to the figures, embodiments for the device 1 according to the invention for connecting a turbine housing with a bearing housing of a turbocharger will be described. In the embodiments of the inventive device 1, as shown in Figs. 1 to 4, the shield 30 assumes mainly the function of a heat shield. In the embodiments illustrated in Figs. 5 and 6, the shield 30 has both the function of a heat shield and the function of a burst protection. All the features of the device 1 according to the invention, which are described with reference to Figs. 1 to 4, are also applicable on the embodiments of Figs. 5 and 6. In particular, the properties of the clamping device 10 are independent of the special design of the protective shield 30 of the different embodiments and may be arbitrarily combined with the embodiments of the protective shield 30 described below.

Fig. 1 is an exemplary illustration of the device 1 according to the invention for connecting a turbine housing to a bearing housing for a turbocharger in an isometric view. It can be seen that the device 1 has a clamping device 10 and a protective shield 30. As is further explained later in connection with Fig. 3 and Fig. 4, the clamping device 10 is designed to connect a turbine housing flange 42 of a turbine housing 40 with a bearing housing flange 52 of a bearing housing 50. As shown in Fig. 1 the protective shield 30 is provided on the clamping device 10. Furthermore, in Fig. 1, an axial direction 94 is shown, arranged along an axis of rotation 94a of the turbocharger. Starting from the axis of rotation 94a, a radial direction 92 and a circumferential direction 96 are furthermore illustrated.

Since the clamping device 10 is located between the turbine housing 40 and bearing housing 50 (see Fig. 3) and, since the protective shield 30 is arranged on the clamping device 10, in the installed state (shown in Fig. 3 and Fig. 4) heat transfer, in particular heat radiation from turbine housing 40 to bearing housing 50, may be reduced by the protective shield 30. Also, a heat transfer to other turbocharger components arranged the axial direction 94 on the bearing housing side of the protective shield 30 in can be reduced. This in turn can diminish heating of the components of the turbocharger, in particular the bearing housing 50 and the compressor housing 60 (see Fig. 4) of the turbocharger. This can result in a larger operating range of the turbocharger and an increase in the life of the turbocharger components. As further described in greater detail below in connection with Figs. 5 and 6, the shield 30 can simultaneously assume the function of burst protection. For example, the shield 30 may be configured to intercept flying parts if the turbine wheel 48 of the turbine ruptures and possibly destroys the turbine housing 40. This can avoid destruction of adjacent components and possibly physical injury to a user. In addition, this security measure allows developers greater freedom in the design of the turbine housing 40 and in the choice of materials for the turbine housing 40. For example, the material thickness (wall thickness) can be kept lower because a failure of the turbine housing 40 is safeguarded by the shield 30. Consequently, material can be saved and the turbine housing 40 can be made lighter. Another advantage is the rapid heating of the turbine housing 40 due to the lower mass.

As can be seen in particular in Fig. 1 and Fig. 2a, the clamping device 10 may be ring- shaped. Further, the protective shield 30 may be ring-shaped. In alternative embodiments, the clamping device 10 and/or the protective shield 30 may be formed according to another shape. For example, the clamping device 10 and/or the protective shield 30 may be formed oval, triangular or rectangular. The configuration of the shape of the clamping device 10 may depend primarily on the shape of the turbine housing flange 42 and/or the bearing housing flange 52. In this case, a ring is generally understood to mean a shape which is formed completely or in sections like a ring along the circumferential direction 96. In this case, forms are explicitly included which have one or more interruptions in the circumferential direction 96. This is for example explained later in more detail in the case of two-piece or multi-part configurations of the clamping device 10 and/or the protective shield 30. In particular, in Fig. 2b is further shown an outer peripheral surface 12 of the clamping device 10, an inner peripheral surface 14 of the clamping device 10 and edge surfaces 16 of the clamping device 10. By "outer" peripheral surface 12 there is meant here a circumferential surface which is oriented outwardly in the radial direction 92. By "inner" peripheral surface 14 there is meant here a circumferential surface, which is oriented inwardly in the radial direction 92. A ring-shaped configuration allows easy attachment of the clamping device 10 to the two flanges 42, 52, since they are normally designed to be round. Furthermore, a ring-shaped clamping device 10 provides, with its outer peripheral surface 12, an advantageous attachment possibility for a protective shield 30. For example, an arrangement of the protective shield 30 directly to a part of the turbine housing 40 or of the bearing housing 50 would be possible only with a much more complex shape of the shield 30 or with the assistance of an additional fastening means, which serves for example as an adapter between the housing and shield 30. A ring-shaped design of the clamping device 10 and/or the protective shield 30 can generally be manufactured with less effort than, for example, a shape adapted to discontinuous contours of the housing. Further, a likewise round shaped turbine housing 40 can be ideally shielded by a ring-shaped configuration of the shield 30.

In the exemplary embodiment shown (see in particular Fig. 2a) the protective shield 30 is arranged, with reference to the rotational axis 94a, in the radial direction 92 outside of the clamping device 10. Furthermore, the protective shield 30 is disposed coaxially about the clamping device 10. In alternative embodiments, the protective shield can also be located elsewhere relative to the clamping device 10. For example, the protective shield 30 may be alternatively or additionally arranged to extend inwardly in the radial direction 92 and/or in the axial direction 94 overlapping with the clamping device 10. Alternatively or additionally, the protective shield 30 can also at least surround the clamping device 10 coaxially. In other words, this means that the protective shield 30 partially surrounds the circumference of the clamp device 10, for example half way, the other half of the circumference not being surrounded by the protective shield 30. The protective shield 30 may for example surround 180° or 270° of the circumference. All embodiments of the protective shield 30, which surround between 60° and 360° of the circumference, are conceivable here.

The protective shield 30 is arranged on the outer peripheral surface 12 of the clamping device 10. In detail, the protective shield 30 is thereby arranged on a part of the outer peripheral surface 12, whose normal vector is directed in the radial direction 92 to the outside. Alternatively or additionally, the protective shield 30 can be arranged on a part of the outer circumferential surface 12 whose normal vector has a direction component in the axial direction 94. Alternatively or additionally, the protective shield 30 may be arranged also on the inner circumferential surface 14 and/or on the edge surfaces 16 of the clamping device 10.

In a preferred embodiment, the protective shield 30 is materially connected with the clamping device 10 by a weld. In alternative embodiments, the protective shield 30 can be connected with the clamping device 10 in alternative cohesive, non-positive or positive connections. In alternative embodiments, the protective shield 30 can be connected with the clamping device 10 also by a combination of a frictional and a positive connection. In alternative versions the protective shield 30 may be made integral with the clamping device 10. As can be seen in particular in Fig. 2a, a peripheral portion of the clamping device 10 which is in contact with the protective shield 30 and a peripheral portion of the clamping device 10 which is surrounded by the protective shield 30 will differ from each other. In particular, as illustrated in the embodiment of Fig. 2a, the peripheral region of the clamping device 10 which is surrounded by the protective shield 30 will be larger than the peripheral portion of the clamping device 10, which is in contact with the protective shield 30. By "larger" is meant, in this case, a larger angle, which includes the respective peripheral portion. In other words, this means that the protective shield 30 can be formed so that a radially outer portion of the shield 30 includes a larger angle in the circumferential direction 96 than a radially inner region of the shield 30. In this regard, in Fig. 2a a radially outer periphery 32 of the shield 30 and a radially inner periphery 34 of the shield 30 can be recognized.

The protective shield 30 in the embodiment of Fig. 2b has a cross-sectional profile 36 that extends from the clamping device 10 in the radial direction 92 and in the axial direction 94. In alternative versions the cross-sectional profile 36, starting from the clamping device 10, may extend only in the radial direction 92. In both latter mentioned cases, the cross- sectional profile 36, starting from the clamping device 10, preferably extends outwardly therefrom in the radial direction 92. In alternative embodiments, for example, when the protective shield 30 is arranged at an inner circumferential surface 14 of the clamping device 10, the protective shield 30 may alternatively or additionally extend radially inwardly 92.

The cross-sectional profile 36 of the protective shield 30 has, in the exemplary embodiment of Fig. 2b a curved, substantially C-shaped course. In alternative embodiments, the cross- sectional profile 36 of protective shield 30 may also have a different curved course or a straight course. The exemplary C-shaped cross-sectional profile 36 of Fig. 2b has, in this case, a concave surface 36a and a convex surface 36b. Alternatively or additionally, the cross-sectional profile 36 may also include fewer or more concave surfaces 36a and/or convex surfaces 36b respectively. The concave surface 36a of the protective shield 30 in the illustrated embodiment is facing the turbine housing 40 in the axial direction 94 in the installed state (see in particular Fig. 3). In alternative embodiments, the concave surface 36a may also be facing a different direction, in particular be facing a another axial direction 94. Such advantageous embodiments can lead to a better heat shielding. By the concave surface 36a of the shield 30 facing the turbine housing 40, a larger heat radiation area can be covered by a protective shield 30 than with a straight cross-sectional profile 36 of comparable extension in the radial direction 92. In other words, these configurations lead to more efficient heat shield when having the same limited dimensions in the radial direction 92 compared to a protective shield 30 with non-curved cross-sectional profile 36, that is, a straight cross-sectional profile 36.

The protective shield 30, as shown in Figs. 1 to 4, may be configured single-layered. The wall thickness of the protective shield 30 may be between 0.5 mm and 3 mm. The wall thickness refers to one layer. Such a configuration allows a simple manufacture. For example, the shield 30 may be manufactured as a sheet metal part, wherein the sheet metal part may have a constant wall thickness. Alternatively, the protective shield 30 may be formed as a MTM (metal injection molding) component. In particular, when the shield 30 is formed as a MTM part, a non-constant wall thicknesses can be provided. This can be advantageous both for the heat protection effect and the function of burst protection, since the wall thickness can be kept thicker or thinner in a targeted manner in arrangement of areas for the design.

Besides the single-layer embodiment of the protective shield 30, an at least partially multilayered, in particular two or three-layer embodiment of the protective shield 30 may be provided. Fig. 6 shows an example of a protective shield 30 with two layers, an outer layer 30-1 and an inner layer 30-11. For example, the shield 30 of Fig. 5 may be made of two plies of sheet metal joined together in a suitable manner. Between the outer layer 30-1 and the inner layer 30-11, a cavity 31 is formed. It is also possible to create multiple cavities, for example, when the heat shield 30 is composed of several sections and/or more than two layers are provided. The embodiment shown in Fig. 6 is designed to be closed at the end facing the clamping device 10 and designed to be open at the end arranged above the turbine housing 40. In alternative embodiments, the cavity 31 or the cavities may be designed to be open at both ends, be designed to be closed at one of the two ends or designed to be closed at both ends. By the multi-layer design of the shield 30 on the one hand, the rigidity and strength (burst protection) and on the other hand, the thermal shielding (heat shield) of the protective shield 30 is improved. In particular, an insulating material 33 may be provided in the cavity 31 or the cavities. The insulating material may, for example, comprise ceramic or comprise glass fiber mats or mica.

As can be seen in particular in Fig. 1 and Fig. 2a, the clamping device 10 can have a first clamp segment 10a and a second clamp segment 10b. Further, the protective shield 30 can include a first shield segment 30a and a second shield segment 30b. Furthermore, when the clamping device 10 and the protective shield 30 have two sections each (10a, 10b, 30a, 30b), the first shield segment 30a can be disposed on the first clamp segment 10a and the second shield section 30b on the second clamp segment 10b. In alternative embodiments, the clamping device 10 and/or the protective shield 30 also may consist of one piece or more than two parts. Various combinations, such as a three-piece clamping device 10 and a one-piece protective shield 30 or a two-piece clamping device 10 and a three-piece protective shield 30, would also be conceivable. For example, the protective shield 30 may surround only a part of the clamping device 10 in the circumferential direction 96, that is, the clamping device 10 surrounds in the radial direction 92, to the outside, an angular section. The protective shield 30 may therefore in embodiments consist of two or more segments, which are arranged distributed over the circumference of the clamping device 10.

The two-part design ensures an easy assembly and/or disassembly of the clamping device 10 to the bearing flange 52 and turbine flange 42. Since the protective shield 30 is also configured in two parts and one shield segment (30a, 30b) can be respectively arranged on one clamp segment (10a, 10b), the protective shield 30 can also easily be assembled together with the clamping device 10 and/or disassembled. If the protective shield 30 is releasably attached, for example, by a screw on the clamping device 10, one or both shield segments can also be mounted or removed independently of the clamping device 10. Thus, the two-part design results in a flexible adaptation of the device 1 to different protective shield requirements, since the protective shield 30 can be removed or replaced by another protective shield 30.

Further, in embodiments, in which the clamping device 10 comprises a first clamp segment 10a and a second clamp segment 10b, the first clamp segment 10a and the second clamp segment 10b are designed to be connected to each other, in particular screwed. Alternatively or additionally, the clamping device 10 can be adapted to being clamped in the circumferential direction 96 by tensioning. This allows bracing of the flanges (42, 52) as explained in greater detail below. Furthermore, the clamping device 10 may include at least one tensioning device 18. The tensioning device 18 can in this case be designed to tension the clamping device 10 in the circumferential direction 96 by pulling or drawing. The two clamp segments (10a, 10b) can thereby be connected at a first attachment side 17a by the tensioning device 18. On a second attachment side 17b, the two clamp segments (10a, 10b) may be designed to be linked by a linking device 19, as shown for example in Fig. 1 and 2a. Alternatively, the two clamp segments (10a, 10b) can also be designed to be directly linked to one another on the second attachment side 17b. The latter can be implemented, for example, by directly hooking the two clamp segments (10a, 10b) into one another.

By these advantageous embodiments, a releasable attachment of the clamping device 10, and thus a releasable attachment of the protective shield 30, is made possible. That is, even if the protective shield 30 is mounted for example by a welded connection to the clamp device 10, it can be removed together with the clamping device 10. Thereupon, the clamping device 10 can be replaced by a different clamping device 10 with a protective shield 30, for example a protective shield 30 having different characteristics and/or other geometric dimension or by a clamping device 10 without protective shield 30.

In embodiments the clamping device 10 may be a band that can be tensioned in the circumferential direction 96. As already mentioned, the clamping device 10 can have surfaces 14 oriented inwardly in the radial direction 92. In the installed state of the clamping device 10 (see Fig. 3), the radially inwardly oriented faces 14 of the clamping device 10 can be in engagement with radially outwardly 92 oriented facing surfaces of the flanges (42, 52). In this regard, in Fig. 3, an outer surface 44 of the turbine housing flange 42 and an outer surface 54 of the bearing housing flange 52 are shown engaged with the radially inwardly oriented surface 14 of the clamping device 10. Thereby, that the clamping device 10 can be tensioned in the circumferential direction 96 by a pulling force, the circumference of the clamping device 10, and, in the case of a ring-shaped clamping device 10, a diameter of the clamping device 10, can be reduced. As a result, a movement of the clamping device 10 in the radial direction 92 is generated inwardly. By a corresponding configuration of the radially inwardly oriented surface 14 and the thus engaging and also correspondingly designed flange outer surfaces (44, 54), the movement of the clamping device 10 in the radial direction 92 inwardly, a movement the flanges (42, 44) towards each other in an axial direction 94 thus also the housings (40, 50) is effected. In other words, in this way, the turbine housing 40 and the bearing housing 50 can be drawn together in the axial direction 94 and braced to each other. More specifically, this is possible because the radially inwardly oriented surfaces 14 are beveled in the region of engagement with the flange outer surfaces (44, 54). That is, the surfaces 14 may have, in the engagement region with the flange outer surfaces (44, 54), a normal vector, having directional portions in each of the radial direction 92 inwardly and in axial directions 94 facing each other. Similarly, the outer surface 44 of the turbine housing flange 42 and the outer surface 54 of the bearing housing flange 52 may be tapered and each having a normal vector whose directional portions are formed radially outwardly 92 and away from each other in axial directions 94 (see Fig. 3).

In alternative embodiments the clamping device 10 may be a band clamp, a pipe clamp or a tensioning band with additional cover band.

In Figs. 5 and 6 embodiments of the shield 30 are shown, which function as burst protection in addition to functioning as a heat shield. The shape and the strength of the shield 30 is configured such that the shield 30 prevents the uncontrolled flying around of parts of the turbine wheel 48 and/or of the turbine casing 40, if this is also destroyed, in the event of bursting of the turbine wheel 48 of the turbine. As shown in Figs. 5 and 6, the shield 30 is so designed that it extends in the axial direction 94 over approximately half the turbine housing 40. In other words, the shield 30 extends in the axial direction so as to radially surround the turbine housing 40 along half its axial extent. The shield 30 should extend over at least one third of the turbine housing 40 axially. Preferably the shield 30 extends over at least half the turbine housing 40. For example, the shield 30 may extend over more than three quarters and more of the turbine housing 40. In particular, the shield 30 should, seen in the axial direction 94, surround at least a portion of the turbine wheel 48 radially outwardly. As a result, the shield 30 advantageously simultaneously fulfills the function of heat shield and burst protection.

As illustrated in the embodiment of Fig. 5, the shield 30 may include stiffener crimps 38. Alternatively or additionally, stiffening ribs may also be provided. Multilayer embodiments of the shield 30 (see, e.g., Fig. 6) can also be provided with stiffening crimps 38 and/or stiffening ribs. On the one hand, the stiffening crimps 38 or stiffening ribs increase the stability and strength of the protective shield 30 in order to securely stop the flying parts. On the other hand, the stiffening ribs or stiffening beads 38 prevent the occurrence of oscillations and vibrations, whereby an unwanted noise is prevented. In Fig. 5, a stiffening crimp 38 is shown in the circumferential direction. The stiffening crimp 38 may extend over the entire circumference or over only a part of the circumference. It is also possible to provide more than one stiffening crimp 38. These can take the form of multiple circumferentially distributed (circumferential segment) arranged stiffening crimps 38 and/or a plurality stiffening crimps 38 arranged distributed in the axial direction 94. Alternatively or additionally, one or more axially extending stiffening crimps may be provided. The same applies to stiffening ribs which can be provided on the protective shield 30 both radially inwardly and radially outwardly in the axial and/or circumferential direction and/or in any other functionally sensible arrangement.

The invention further comprises a charging device 100, in particular an exhaust gas turbocharger, which is shown in Fig. 4. The charging device 100 comprises a turbine housing 40, a compressor housing 60, a bearing housing 50 and a device 1 according to any one of the preceding embodiments. The turbine housing 40 and the bearing housing 50 are detachably connected by the device 1.

Although the present invention has been described above and defined in the appended claims, it should be understood that the invention may alternatively be defined according to the following embodiments: 1. Device (1) for connecting a turbine housing (40) to a bearing housing (50) for a turbocharger comprising:

a clamping device (10) for connecting a turbine housing flange (42) to a bearing housing flange (52),

characterized in that the device (1) further comprises a protective shield (30), which is provided on the clamping device (10).

2. Device (1) according to embodiment 1, characterized in that the clamping device (10) is ring-shaped. 3. Device (1) according to any one of the preceding embodiments, characterized in that the protective shield (30) is annular.

4. Device (1) according to any one of the preceding embodiments, characterized in that the protective shield (30) is arranged, with reference to the axis of rotation (94a) of the turbocharger, starting radially outside the clamping device (10).

5. Device (1) according to any one of the preceding embodiments, characterized in that the protective shield (30) is arranged coaxially around the clamping device (10). 6. Device (1) according to any of the preceding embodiments, characterized in that the protective shield (30) coaxially surrounds at least part of the circumference of the clamping device.

7. Device (1) according to any one of the preceding embodiments, characterized in that the protective shield (30) is arranged on an outer surface (12) of the clamping device (10), whose normal vector is oriented outwardly in the radial direction (92). 8. Device (1) according to any one of the preceding embodiments, characterized in that the protective shield (30) is form fittingly, force fittingly, or materially connected with the clamping device (10), in particular by a welded connection. 9. Device (1) according to any one of the preceding embodiments, characterized in that the protective shield (30) is integral with the clamping device (10).

10. Device (1) according to any one of the preceding embodiments, characterized in that the protective shield (30) has a cross-sectional profile (36) extending from the clamping device (10) in the radial direction (92), preferably extending in radial (92) and axial (94) directions.

11. Device (1) according to any one of the preceding embodiments, characterized in that the protective shield (30) has a curved cross-sectional profile (36).

12. Device (1) according to any one of the preceding embodiments, characterized in that the protective shield (30) has a substantially C-shaped cross-sectional profile (36).

13. Device (1) according to any one of embodiments 10 to 12, characterized in that the cross-sectional profile (36) has a concave surface (36a) which in the installed state faces the turbine housing (40) in the axial direction (94).

14. Device according to any of the preceding embodiments, characterized in that the shape and the strength of the protective shield (30) is configured so that the protective shield (30) can serve as a burst protection.

15. Device according to any of the preceding embodiments, characterized in that the protective shield (30) is configured to project in the axial direction (94) over at least a third, preferably over at least half, the turbine housing (40).

16. Device according to any of the preceding embodiments, characterized in that the protective shield (30) is formed at least partially in several layers, in particular two or three layers. 17. Device of embodiment 16, characterized in that between the layers (30-1, 30-11) of the protective shield (30) one or more cavities (31) are formed, in particular, the cavity or cavities are at least partially filled with an insulating material (33). 18. Device according to any of the preceding embodiments, characterized in that the protective shield (30) is made as a sheet metal part, as an MEVI part or a precision casting part.

19. Device according to any of the preceding embodiments, characterized in that the protective shield (30) one or more stiffening beads (38) comprising and/or stiffening ribs.

20. Device (1) according to any one of the preceding embodiments, characterized in that the clamping device (10) comprises a first clamp segment (10a) and a second clamp segment (10b).

21. Device (1) according to any one of the preceding embodiments, characterized in that the protective shield (30) comprises a first shield segment (30a) and a second shield segment (30b). 22. Device (1) according to embodiment 21, when dependent on embodiment 20, characterized in that the first shield segment (30a) is provided on the first clamp segment (10a) and the second shield segment (30b) is provided on the second clamp segment (10b).

23. Device (1) according to embodiment 20, characterized in that the first clamp segment (10a) and the second clamp segment (10b) are designed to be connected to each other, in particular to be screwed.

24. Device (1) according to any one of the preceding embodiments, characterized in that the clamping device (10) is designed to be tensioned in the circumferential direction (96).

25. Device (1) according to any one of the preceding embodiments, characterized in that the clamping device (10) comprises at least one tensioning device (18) which is designed to tension the clamping device (10) in the circumferential direction (96). 26. Device (1) according to any one of the preceding embodiments, characterized in that the clamping device (10) is a band tensionable in the circumferential direction (96).

27. Device (1) according to embodiment 26, characterized in that the clamping device (10) has radially inwardly oriented surfaces (14) engageable with radially outwardly oriented surfaces (44, 54) of the flanges (42, 52), whereby the turbine housing (40) and the bearing housing (50) are clamped to each other in the axial direction (94).

28. Device (1) according to any one of the preceding embodiments, characterized in that the clamping device (10) is a band clamp.

29. Charging device (100), in particular an exhaust gas turbocharger with a turbine housing (40), a compressor housing (60), a bearing housing (50) and a device (1) according to any one of the preceding embodiments, wherein the turbine housing (40) and the bearing housing (50) are connected by the device (1).

Claims

1. Device (1) for connecting a turbine housing (40) with a bearing housing (50) for a turbocharger comprising:

characterized in that the device (1) further comprises a protective shield (30) arranged on the clamping device (10).

2. Device (1) according to claim 1, characterized in that the clamping device (10) is ring-shaped and/or that the protective shield (30) is annular.

3. Device (1) according to any one of the preceding claims, characterized in that the protective shield (30) is arranged, with reference to the axis of rotation (94a) of the turbocharger, starting radially outside the clamping device (10).

4. Device (1) according to any one of the preceding claims, characterized in that the protective shield (30) is positively, non-positive or cohesively connected with the clamping device (10), in particular by a welded joint.

5. Device (1) according to any one of the preceding claims, characterized in that the protective shield (30) has a cross-sectional profile (36) extending from the clamping device (10) in the radial direction (92), preferably in the radial (92) and axial directions (94).

6. Device (1) according to any one of the preceding claims, characterized in that the protective shield (30) has a bent cross-sectional profile (36).

7. Device according to any one of the preceding claims, characterized in that the shape and the strength of the shield (30) are designed so that the protective shield (30) may serve as a burst protection.

8. Device according to any one of the preceding claims, characterized in that the protective shield (30) is configured to extend in the axial direction (94) over at least a third, preferably at least half, the turbine housing (40).

9. Device according to any one of the preceding claims, characterized in that the protective shield (30) is formed at least partially in several layers, in particular two or three layers.

10. Apparatus according to claim 9, characterized in that between the layers (30-1, 30-11) of the protective shield (30) one or more cavities (31) are formed, in particular, wherein the cavity or cavities are at least partially filled with an insulating material (33).

11. Device according to any one of the preceding claims, characterized in that the protective shield (30) has one or more stiffening crimps (38) and/or stiffening ribs.

12. Device (1) according to any one of the preceding claims, characterized in that the clamping device (10) comprises a first clamp segment (10a) and a second clamp segment (10b) and/or that the protective shield (30) comprises a first shield section (30a) and a second shield section (30b).

13. Device (1) according to claim 12, characterized in that the first shield section (30a) is provided on the first clamp segment (10a) and second shield segment (30b) is provided on the second clamp segment (10b).

14. Device (1) according to any one of the preceding claims, characterized in that the clamping device (10) is designed to be tensioned in the circumferential direction (96).

15. Charging device (100), in particular exhaust gas turbocharger with a turbine housing (40), a compressor housing (60), a bearing housing (50) and a device (1) according to any one of the preceding claims, wherein the turbine housing (40) and the bearing housing (50) are connected by the device (1).