Exhaust gas turbocharger and support structure for an exhaust gas turbocharger

Abstract

Exhaust gas turbocharger, comprising a turbine (11) for expanding exhaust gas and generating energy, and a compressor (1) for compressing charge air using the energy generated in the turbine (11), wherein the turbine (11) comprises a multi-part turbine housing (10) with an inlet housing and an outlet housing (9) and a turbine rotor positioned in the turbine housing (10), and wherein the compressor (1) comprises a multi-part compressor housing (2) with a bearing housing (3) and a spiral housing (4) and a compressor rotor (7) positioned in the compressor housing (2) and coupled to the turbine rotor, characterized by a support structure (12) clamping the turbine housing (10) and the compressor housing (2) via compressive forces, which has a first annular flange (13) engaging on the outside of the compressor housing (2) and a second annular flange (14) engaging on the outside of the turbine housing (10),which are connected to each other by tension-pressure anchors (15) under tension of the turbine housing (10) and the compressor housing (2), wherein the support structure (12) is mounted on the outside of the compressor housing (2) and turbine housing (10) of an existing exhaust gas turbocharger in order to provide containment protection or burst protection for the same.

Description

[0001] The invention relates to an exhaust gas turbocharger and a support structure for an exhaust gas turbocharger.

[0002] An exhaust gas turbocharger consists of a turbine and a compressor. The turbine of the exhaust gas turbocharger expands the exhaust gas leaving the engine and recovers energy during this expansion. The compressor of an exhaust gas turbocharger compresses the intake air supplied to the engine using the energy recovered in the turbine. The turbine has a multi-part turbine housing and a turbine rotor positioned within it. The compressor has a multi-part compressor housing and a compressor rotor positioned within it. The compressor rotor and turbine rotor are coupled via a shaft. During the operation of an exhaust gas turbocharger, there is a risk that, for example, the compressor rotor will break, and fragments of the compressor rotor will penetrate the compressor housing and be ejected into the surrounding area of ​​the exhaust gas turbocharger.A similar type of damage can also occur in the turbine area of ​​the exhaust gas turbocharger. To address this problem, the compressor housing and, if applicable, the turbine housing of exhaust gas turbochargers known from practical experience are designed in such a way that damage to the respective housing is not to be expected, and even if the rotor breaks, fragments of it cannot penetrate the housing. However, this increases the weight of the exhaust gas turbocharger, and these measures can only be implemented in newly designed exhaust gas turbochargers. Existing, older exhaust gas turbochargers, on the other hand, cannot be redesigned, meaning they lack this protection, and therefore, in the event of damage, fragments can be released into the surrounding environment.

[0003] German patent application DE 10 2013 013 571 A1 discloses a solution for protecting older, existing exhaust gas turbochargers in the event of damage, preventing fragments from being released into the environment. This solution proposes that the compressor housing and / or the turbine housing be at least partially encased by at least one metal ring mesh.

[0004] Furthermore, reference is made to DE 36 31 356 A1, DE 531 262 A, DE 14 26 808 A, WO 2009 101 167 A1, DE 199 25 684 A1, EP 1 293 681 A1 and US 4 171 936 A as relevant prior art.

[0005] Based on this, the present invention aims to create a novel exhaust gas turbocharger and a support structure for an exhaust gas turbocharger.

[0006] This problem is solved by an exhaust gas turbocharger according to claim 1.

[0007] According to the invention, the exhaust gas turbocharger has a support structure that clamps the turbine housing and the compressor housing via compressive forces. This support structure comprises a first annular flange engaging the outside of the compressor housing and a second annular flange engaging the outside of the turbine housing. These annular flanges are connected to each other by tension-compression anchors, clamping the turbine housing and the compressor housing together. The exhaust gas turbocharger according to the invention offers particularly advantageous protection in the event of damage to the turbocharger, preventing fragments from escaping into the environment. The support structure of the exhaust gas turbocharger according to the invention is particularly suitable for retrofitting existing, older exhaust gas turbochargers.

[0008] Preferably, the first annular flange engages the outer surface of the compressor housing's spiral casing, and the second annular flange engages the outer surface of the turbine housing's exhaust casing. The tensile-compression anchors extend outside the compressor housing and the turbine housing. This provides particularly effective protection for exhaust gas turbochargers in the event of damage and is especially suitable for retrofitting existing, older exhaust gas turbochargers.

[0009] In a further advantageous development, the support structure braces the turbine housing and the compressor housing, or their respective housing components, with compressive forces in such a way that the compressive stresses in the housings or housing components caused by these forces are greater than the tensile stresses acting on the housings or housing components in the event of damage. This allows for a simple and reliable prevention of the braced housings or housing components bursting in the event of exhaust gas turbocharger damage, thus preventing fragments of the compressor or turbine rotor from penetrating the respective housing. This is particularly advantageous for protecting existing, older exhaust gas turbochargers in the event of damage.

[0010] In a further advantageous development, the compressor housing comprises an insert made of a ductile material, mounted on the spiral casing. This ensures that, in the event of damage to the compressor rotor, fragments impacting the insert result in a surface load rather than a point load on the insert. Thus, in the event of damage, forces acting on the compressor housing via the insert can be advantageously transferred into the support structure. This provides particularly effective protection for the exhaust gas turbocharger in the event of damage.

[0011] The support structure according to the invention for an exhaust gas turbocharger is defined in claim 10.

[0012] Preferred embodiments of the invention are described in the dependent claims and the following description. Exemplary embodiments of the invention are explained in more detail with reference to the drawing, without being limited thereto. The drawing shows: Fig. 1: a partial cross-section through an exhaust gas turbocharger according to the state of the art; Fig. 2: An external view of an exhaust gas turbocharger according to the invention.

[0013] The invention relates to an exhaust gas turbocharger. An exhaust gas turbocharger comprises a turbine and a compressor. The turbine of an exhaust gas turbocharger has a multi-part turbine housing and a turbine rotor housed within the turbine housing. The compressor of an exhaust gas turbocharger comprises a compressor housing and a compressor rotor housed within the compressor housing. The turbine rotor and compressor rotor are coupled together. Energy recovered in the turbine during the expansion of the exhaust gas is used in the compressor to compress the charge air.

[0014] Fig. Figure 1 shows a partial cross-section of an exhaust gas turbocharger in the area of ​​a compressor 1, namely a compressor housing 2, wherein the in Fig. The compressor housing 2 shown in Figure 1 is composed of a bearing housing 3 and a spiral housing 4.

[0015] Fig. Figure 1 further shows an insert 5 engaging the spiral casing 4 of the compressor housing 2, as well as an element of a silencer 6 also engaging the spiral casing 4 of the compressor housing 2. Also shown is Fig. Figure 1 shows a compressor rotor 7, wherein the compressor rotor 7, together with the insert 5, defines a flow channel 8 for charge air to be compressed. A discharge housing 9 of a turbine housing 10 of a turbine 11 of the exhaust gas turbocharger engages the bearing housing 3 of the compressor housing 2, wherein the turbine housing 9, in addition to the discharge housing 10, has an inlet housing (not shown). Furthermore, the turbine 11 comprises a turbine rotor (not shown) which is coupled to the compressor rotor 7.

[0016] The in Fig. The basic structure of an exhaust gas turbocharger shown in Figure 1 is familiar to the expert addressed here.

[0017] To provide burst protection or containment protection for the exhaust gas turbocharger, the present invention provides that the exhaust gas turbocharger comprises a support structure 12 by means of which the turbine housing 10 and the compressor housing 2 are clamped together by means of compressive forces. For this purpose, the support structure 12 has a first annular flange 13 engaging the outside of the compressor housing 2 and a second annular flange 14 engaging the outside of the turbine housing 10. The first annular flange 13 is connected to the compressor housing 2, namely to its spiral casing 4, whereas the second annular flange 14 is connected to the turbine housing 10, namely to its outlet casing 9. The first ring flange 13 engages the outside of the compressor housing 2, namely the spiral housing 4, via first screw connections, while the second ring flange 14 engages the outside of the turbine housing 10, namely the exhaust housing 9, via a second screw connection.

[0018] The two ring flanges 13, 14 of the support structure 12 are connected to each other via several tension-compression anchors 15, namely by bracing the turbine housing 10 and the compressor housing 2 by introducing compressive stresses into these housings 2, 10, which are caused by compressive forces. The support structure 12, which acts on the outside of the compressor housing 2 and turbine housing 10, thus clamps the spiral casing 4 of the compressor housing 2 and the outflow casing 9 of the turbine housing 10 together in the shown, preferred embodiment, by means of compressive forces, whereby these compressive forces, which are introduced into the housing parts, namely into the spiral casing 4 and the outflow casing 9, via the tensile-compression anchors 15 and the annular flanges 13, 14 of the support structure 12, cause compressive stresses in these housing parts which are greater in magnitude than the tensile stresses acting on the housings 2, 10 or the housing parts 4, 9 in the event of damage.In the event of damage, the tensile forces and resulting tensile stresses acting on the housings of the exhaust gas turbocharger or the aforementioned housing parts can therefore be compensated by the compressive stresses introduced into the housings 2, 10 or the housing parts 4, 9 by the support structure 12, so that there is no danger of the housings 2, 10 or the housing parts 4, 9 bursting in the event of damage.

[0019] The first annular flange 13, which engages the outside of the compressor housing 2, in particular the spiral casing 4 of the compressor housing 2, primarily absorbs axial forces acting on the compressor housing 2 in the event of damage, whereas the second annular flange 14, which engages the outside of the turbine housing 10 or the outflow casing 9 thereof, primarily absorbs axial forces acting on the turbine housing 10 in the event of damage.

[0020] Therefore, if, in the event of damage to the exhaust gas turbocharger, the compressor rotor 7 or the turbine rotor (not shown) bursts, axial forces caused by fragments of these rotors impacting the housings can be safely absorbed by the support structure 12. In the event of damage, for example, fragments of the compressor rotor 7 can initially reach the insert 5 and, via the insert 5, exert tensile forces and thus tensile stresses on the spiral casing 4 of the compressor housing 2. Furthermore, such fragments can reach the bearing housing 3 of the compressor housing 2, which is connected to the exhaust housing 9 of the turbine housing 10. This ultimately introduces tensile forces and thus tensile stresses into the housings or housing components, which can lead to their destruction.The support structure 12 according to the invention provides protection against this, by means of which the spiral casing 4 of the compressor housing 2 and the outlet casing 9 of the turbine housing 10 are clamped together in a defined manner by introducing compressive stresses into the housings or housing parts. As already described, the annular flange 14 absorbs forces that are introduced into the outlet casing 9 of the turbine housing 10, whereas the annular flange 13 primarily absorbs forces that act on the spiral casing 4 of the compressor housing 2. A suitable preload can be set in the housings 2, 10 or the housing parts 4, 9 by means of a suitable number of tie rods 15, which connect the two annular flanges 13, 14 together by clamping the housings or housing parts.

[0021] A preferred embodiment is one in which the insert 5 of the compressor housing 2, which is mounted on the spiral housing 4, is made of a ductile material. This ensures that, in the event of damage to the compressor rotor 7, fragments impacting the insert 5 do not result in a point load but rather a surface load on the insert 5, thereby distributing the corresponding forces uniformly into the support structure 12, where they can be absorbed. This provides particularly advantageous containment or burst protection for an exhaust gas turbocharger.

[0022] Furthermore, it is advantageous if the outflow housing 9 of the turbine housing 10 is made of a ductile material in order to be able to introduce loads in the area of ​​the turbine housing 10 uniformly as a surface load into the support structure 12.

[0023] The invention is particularly suitable for retrofitting existing, older exhaust gas turbochargers with effective burst protection or containment protection. The support structure 12 according to the invention can be easily mounted externally on the compressor housing 2 and turbine housing 10 of an existing exhaust gas turbocharger to provide containment or burst protection for it. Reference symbol list 1 compressor 2 compressor housings 3 bearing housings 4 spiral casings 5 insert pieces 6 silencers 7 Compressor rotor 8 Flow channel 9 exhaust housings 10 turbine housings 11 Turbine 12 Support structure 13 Ring flange 14 ring flange 15 tension-compression anchors

Claims

[1] Exhaust gas turbocharger, comprising a turbine (11) for expanding exhaust gas and generating energy, and a compressor (1) for compressing charge air using the energy generated in the turbine (11), wherein the turbine (11) comprises a multi-part turbine housing (10) with an inlet housing and an outlet housing (9) and a turbine rotor positioned in the turbine housing (10), and wherein the compressor (1) comprises a multi-part compressor housing (2) with a bearing housing (3) and a spiral housing (4) and a compressor rotor (7) positioned in the compressor housing (2) and coupled to the turbine rotor, characterized bya support structure (12) that clamps the turbine housing (10) and the compressor housing (2) by means of compressive forces, having a first annular flange (13) acting on the outside of the compressor housing (2) and a second annular flange (14) acting on the outside of the turbine housing (10), which are connected to each other by tension-compression anchors (15) under tension of the turbine housing (10) and the compressor housing (2), wherein the support structure (12) is mounted on the outside of the compressor housing (2) and turbine housing (10) of an existing exhaust gas turbocharger in order to provide containment protection or burst protection for the same. [2] Exhaust gas turbocharger according to claim 1, characterized by , that the first ring flange (13) engages the outer surface of the spiral casing (4) of the compressor casing (2). [3] Exhaust gas turbocharger according to claim 1 or 2, characterized by , that the second ring flange (14) engages the outside of the outflow casing (9) of the turbine casing (10). [4] Exhaust gas turbocharger according to one of claims 1 to 3, characterized by , that the tensile / compression anchors (15) extend outside the compressor housing (2) and outside the turbine housing (10). [5] Exhaust gas turbocharger according to any one of claims 1 to 4, characterized by , that the first ring flange (13) absorbs axial forces acting on the compressor housing (2) in the event of damage. [6] Exhaust gas turbocharger according to any one of claims 1 to 5, characterized by , that the second ring flange (14) absorbs axial forces acting on the turbine housing (10) in the event of damage. [7] Exhaust gas turbocharger according to any one of claims 1 to 6, characterized by, that the support structure (12) braces the turbine housing (10) and the compressor housing (2) or the corresponding housing parts (4, 9) thereof with compressive forces in such a way that the compressive stresses caused by the compressive forces in the housings (2, 10) or housing parts (4, 9) are greater in magnitude than the tensile stresses acting on the housings (2, 10) or housing parts (4, 9) in the event of damage. [8] Exhaust gas turbocharger according to any one of claims 1 to 7, characterized by , that the compressor housing (2) comprises an insert (5) made of a ductile material mounted on the spiral housing (4) of the same. [9] Exhaust gas turbocharger according to any one of claims 1 to 8, characterized by , that the outflow casing (9) of the turbine casing (10) is made of a ductile material. [10] Support structure (12) for an exhaust gas turbocharger comprising a turbine (11) for expanding exhaust gas and generating energy, and a compressor (1) for compressing charge air using the energy generated in the turbine (11), wherein the turbine (11) comprises a multi-part turbine housing (10) and a turbine rotor positioned in the turbine housing (10), and wherein the compressor (1) comprises a multi-part compressor housing (2) and a compressor rotor (7) positioned in the compressor housing (2) and coupled to the turbine rotor, wherein the support structure (12) clamps the turbine housing (10) and the compressor housing (2) by means of compressive forces, and wherein the support structure (12) comprises a first annular flange (13) mountable on the outside of the compressor housing (2) and a second annular flange (14) mountable on the outside of the turbine housing (10),which are connected to each other by tension-pressure anchors (15) under tension of the turbine housing (10) and the compressor housing (2), wherein the support structure (12) is mounted on the outside of the compressor housing (2) and turbine housing (10) of an existing exhaust gas turbocharger in order to provide containment protection or burst protection for the same.

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