Exhaust turbine and turbocharger

Abstract

An aspect of an exhaust gas turbine according to the present disclosure comprises a rotating shaft, a turbine wheel mounted on an end face of the rotating shaft, a turbine housing in which a worm section is formed on an outer circumferential face of the turbine wheel, a bearing housing that accommodates a bearing supporting the rotating shaft, a fastening element for joining a first flange section of the turbine housing and a second flange section of the bearing housing, and a heat shielding plate having an outer circumferential edge section clamped between the first flange section and the second flange section, wherein, in a first cross-section passing through a center of the rotating shaft and a tongue section of the turbine housing along an axial direction of the rotating shaft, in one case,in which an innermost position in a radial direction of the rotating shaft in a contact surface between the first flange section and the outer circumferential edge section of the heat shield is set such that it is a first inner sealing end, an innermost position in the radial direction in a contact surface between the second flange section and the outer circumferential edge section of the heat shield is set such that it is a second inner sealing end, and a inner sealing end located on an outer side in the radial direction is set such that it is a sealing end, the inner sealing end is arranged on an outer side with respect to the tongue section in the radial direction.

Description

Technical field

[0001] The present disclosure relates to an exhaust gas turbine and a turbocharger containing the exhaust gas turbine. State of the art

[0002] A heat shield is inserted between a turbine housing of an exhaust gas turbocharger and a bearing housing to prevent exhaust gas flowing inside the turbine housing from escaping to the bearing housing side, or to prevent heat held in the exhaust gas from spreading to the bearing housing.

[0003] PTLs 1 and 2 disclose a fastening method in which a flange section formed at a turbine housing and a flange section formed at a bearing housing are fastened to each other in a state in which a heat shield plate is inserted between the flange sections formed at a component between the turbine housing and the bearing housing by using an annular coupling element having a cross-section with a truncated V-shape. List of citations from patent literature [PTL 1] Japanese unexamined patent application publication no. 2009-167971 [PTL 2] Japanese Unexamined Patent Application Publication No. 2012-117483 Summary of Invention Technical problem

[0004] In the turbine housing, a tongue section is formed at the interface between a screw channel and an exhaust gas inlet channel. Here, the exhaust gas flows from the screw channel into the exhaust gas inlet channel, which houses a turbine wheel. Due to the heat of the exhaust gas, uneven thermal deformation occurs in the vicinity of the tongue section. This can cause uneven deformation of the flange section, which is formed on the component between the turbine housing and the bearing housing, and of the coupling element. Consequently, a problem arises in terms of ensuring a reliable seal between the flange section and the heat shield. Furthermore, the clamping force of the coupling element may become uneven or insufficient in one direction around the rotating shaft, thus compromising the sealing performance.

[0005] The present invention was made in view of the above circumstances, and one object of the present invention is to solve the above problems and to ensure sealing performance between a turbine housing and a bearing housing with respect to thermal deformation in the vicinity of a tongue section due to heat from an exhaust gas. Solution to the problem

[0006] To accomplish the above task, according to one aspect of the present disclosure, an exhaust gas turbine is provided, comprising: a rotating shaft; a turbine wheel mounted on an end face of the rotating shaft; a turbine housing that accommodates the turbine wheel and in which a worm gear section, introducing an exhaust gas to the turbine wheel, is formed on an outer circumferential face of the turbine wheel; a bearing housing that accommodates a bearing supporting the rotating shaft and that is provided adjacent to the turbine housing; a fastening element for joining together a first flange section of the turbine housing and a second flange section of the bearing housing; and a heat shield plate arranged between the turbine housing and the bearing housing, having an outer circumferential edge section that is clamped between the first flange section and the second flange section.wherein, in a first cross-section along an axis direction of the rotating shaft passing through a center of the rotating shaft and a tongue section of the turbine casing, in a case where an innermost position in a radial direction of the rotating shaft (hereinafter simply referred to as a "radial direction") in a contact surface between the first flange section and the outer circumferential edge section of the heat shield is set to be a first inner seal end, an innermost position in the radial direction in a contact surface between the second flange section and the outer circumferential edge section of the heat shield is set to be a second inner seal end, and a inner seal end located on an outer surface in the radial direction is set to be a inner seal end from the first inner seal end and the second inner seal end,The inner end of the seal is arranged on an outer surface in the radial direction with respect to the tongue section. Advantageous effects of the invention,

[0007] According to aspects of the exhaust gas turbine and the supercharger as disclosed herein, even if uneven thermal deformation occurs in the vicinity of the tongue section formed in the turbine housing through which an exhaust gas flows, the sealing performance of a sealing surface formed on a component between the turbine housing and the bearing housing, and between the flange section and the heat shield plate, can be maintained at a high level. Brief description of the drawings Fig. Figure 1 is a schematic configuration diagram of an engine that includes a supercharger, according to one embodiment. Fig. Figure 2 is a vertical sectional view showing part of the charger according to the embodiment. Fig. Figure 3 is a vertical sectional view showing an enlarged portion of an exhaust gas turbine section according to the embodiment. Fig. Figure 4 is a top view of a configuration example of a tongue section formed in a turbine casing, viewed from above. Fig. 5A is a top view of another configuration example of the tongue section when viewed from above. Fig. 5B is a top view, yet another configuration example of the tongue section when viewed from above. Fig. Figure 6 is a vertical sectional view showing an enlarged portion of the exhaust turbine section according to the embodiment. Fig. Figure 7 is a front view of a fastening element according to one embodiment. Fig. Figure 8 is a vertical sectional view showing an enlarged portion of the exhaust turbine section according to the embodiment. Description of embodiments

[0008] Some embodiments of the present invention are described below with reference to the accompanying drawings. It should be noted that the dimensions, materials, shapes, relative arrangements, and the like of components described in the embodiments or shown in the drawings are not intended to limit the scope of protection of the present invention, but are merely exemplary.

[0009] For example, an expression that specifies a relative arrangement or an absolute arrangement, such as "in a direction", "along a direction", "parallel", "perpendicular", "center", "concentric" or "coaxial", does not only strictly represent such an arrangement, but also a state shifted relatively by a tolerance or by an angle or distance to the extent that the same function can be obtained.

[0010] For example, expressions such as "identical", "equal" and "homogeneous", which indicate that things are in the same state, do not only represent a strictly identical state, but also a state in which there is a tolerance or difference in the extent to which the same function can be maintained.

[0011] For example, an expression that specifies a shape, such as a square shape or a cylindrical shape, does not only represent a shape, such as a square shape or a cylindrical shape, in a strictly geometric sense, but also a shape that includes concave and convex sections, chamfered sections, or the like, to the extent that the same effects can be obtained.

[0012] However, the expressions “provided with”, “contain”, “comprise”, “include” or “exhibit” of one component are not exclusive expressions that exclude the presence of other components.

[0013] Fig. Figure 1 is a schematic configuration diagram of an engine containing a supercharger, according to one embodiment, and Fig. Figure 2 is a vertical sectional view showing part of the charger.

[0014] In Fig. Figure 1 has an engine 10, which includes a supercharger 30, for example four cylinders 12a, 12b, 12c and 12d within an engine body 14, and compressed air is supplied to the four cylinders via an air supply distributor 18. The compressed air is supplied by a compressor section 32, which is part of the supercharger 30. Fuel air is supplied to the compressor section 32, the fuel air is compressed in the compressor section 32, and the compressed air is supplied to the cylinders 12a to 12d via an air supply pipe 16 and the air supply distributor 18. An exhaust gas e, which is discharged from each of the cylinders 12a to 12d, is sent via an exhaust gas distributor 20 and an exhaust gas pipe 22 to an exhaust gas turbine section 34, which configures part of the supercharger 30, and rotates a turbine wheel 40 housed in a turbine casing 42.

[0015] As in Fig. As shown in Figure 2, the supercharger 30 contains the exhaust gas turbine section 34, which is located on one end side (an end section side in which an arrow b is shown). Fig. 2 in the direction indicated) of a rotating shaft 36. The exhaust gas turbine section 34 contains the turbine wheel 40, which is mounted on one end of the rotating shaft 36, and the turbine housing 42, which accommodates the turbine wheel 40. The compressor section 32 is located on the other end (one end section side in the direction indicated by an arrow c in Fig. (in the direction specified in 2) the rotating shaft 36 is provided, and the turbine wheel 40 is connected via the rotating shaft 36 to a compressor wheel 32b, which is housed within a compressor casing 32a. The compressor wheel 32b is rotated by the rotation of the turbine wheel 40, and the air for fuel a is drawn into the compressor casing 32a by the rotation of the compressor wheel 32b and compressed by the compressor wheel 32b, and the compressed air is supplied to each of the cylinders 12a to 12d.

[0016] As in Fig. As shown in Figure 2, the turbine housing 42 has a screw section 44 formed on an outer circumferential face of the turbine wheel 40. The turbine housing 42 contains an exhaust gas inlet section 46 within the screw section 44. Inside the exhaust gas inlet section 46, several blades 48 are arranged radially along a circumferential direction of the rotating shaft 36 (hereinafter simply referred to as a "circumferential direction") on an outer circumferential face of the turbine wheel 40, and an exhaust gas inlet channel 50 is formed between each pair of blades 48. The exhaust gas e flows from a flow path formed in the screw section 44 into the exhaust gas inlet channel 50 and then flows out of the exhaust gas inlet channel 50 after rotation of the turbine wheel 40.

[0017] A bearing housing 38 is adjacent to the turbine housing 42 on the other side (one side in which the arrow c is shown). Fig. 2 specified direction) of the turbine housing 42. A bearing 52, which rotatably supports the rotating shaft 36, is housed in the bearing housing 38. The compressor section 32 is provided on the other side of the bearing housing 38. In Fig. Reference numeral O indicates a central axis which is a center of rotation of the rotating shaft 36.

[0018] The charger 30 according to the in Fig. In the embodiment shown in Figure 2, a twin-screw type supercharger is used, and two exhaust gas flow paths, a rear exhaust gas flow path 54 and a front exhaust gas flow path 56, are formed in the screw section 44. In this case, the exhaust gas distributor 20 and the exhaust gas pipe 22 are divided into two systems, and the exhaust gas flow path formed by the exhaust gas distributor and the exhaust pipe of one system communicates with the rear exhaust gas flow path 54, and the exhaust gas flow path formed by the exhaust gas distributor and the exhaust pipe of the other system communicates with the front exhaust gas flow path 56.In the twin screw type, the exhaust gas flow paths are designed so that they have the same flow rate for the exhaust gases flowing through the rear exhaust gas flow path 54 and the front exhaust gas flow path 56, so that there is no pressure difference between the pressure of the exhaust gas flowing through the rear exhaust gas flow path 54 and the pressure of the exhaust gas flowing through the front exhaust gas flow path 56.

[0019] In the screw section 44, the flue gas flow path, formed in a spiral shape, is gradually narrowed towards a downstream side, so that the flue gas flows into the flue gas inlet channel 50 in a state of acceleration. A rear tongue section 58 and a front tongue section 60 are each formed on a section that is a terminal section (coiled section) of the rear flue gas flow path 54 and the front flue gas flow path 56, respectively, and that is an inlet of the flue gas inlet channel 50.

[0020] The in Fig. The embodiment shown in Figure 2 is an embodiment that is applied to a twin-screw turbocharger. However, the exhaust gas turbine according to the present disclosure can also be applied to a single-screw turbocharger.

[0021] In Fig. 2 is a first flange section 62 in the other side end section (the end section in the direction indicated by the arrow c in Fig. 2 is formed) of the turbine casing 42, and a second flange section 64 is formed in a side end section (the end section in the direction indicated by arrow b in Fig. 2) of the bearing housing 38. Both flange sections 62 and 64 are fastened to each other by a fastening element 66, thus connecting the turbine housing 42 and the bearing housing 38. A heat shield 68 is arranged between the first flange section 62 and the second flange section 64, which are fastened to each other by the fastening element 66. That is, an outer circumferential edge section 68a of the heat shield 68 is clamped between both flange sections 62 and 64.

[0022] Fig. Figure 3 corresponds to a vertical section view, in which the surroundings of section A are shown. Fig. Figure 2 is further enlarged and shows an exhaust gas turbine section 34a according to one embodiment. That is to say, Fig. Figure 3 shows a cross-section along the axis direction of the rotating shaft 36 (a direction along the central axis O, hereinafter simply referred to as an “axis direction”), which is a cross-section (a first cross-section) passing through the center (the central axis O) of the rotating shaft 36 and the rear tongue section 58. Furthermore, in Fig. 3 The representation of the rotary shaft 36 and the turbine wheel 40 has been omitted, and the reference numeral O indicates the position of the central axis O of the rotary shaft 36 when the rotary shaft 36 is arranged.

[0023] As in Fig. As shown in Figure 3, the first flange section 62 and the outer circumferential edge section 68a of the heat shield 68 are in contact with each other in a partial area in the radial direction, and a contact surface between the first flange section 62 and the outer circumferential edge section 68a of the heat shield 68 forms a first sealing surface S1. Furthermore, on the side opposite the first sealing surface S1 with respect to the outer circumferential edge section 68a, the second flange section 64 and the outer circumferential edge section 68a of the heat shield 68 are in contact with each other in a partial area in the radial direction, and a contact surface between the second flange section 64 and the outer circumferential edge section 68a of the heat shield 68 forms a second sealing surface S2. Fig. 3. Point Si1 indicates an innermost position (a first inner sealing end) in the radial direction in the contact surface (the first sealing surface S1) between the first flange section 62 and the outer circumferential edge section 68a of the heat shield 68. Point Si2 indicates an innermost position (a second inner sealing end) in the radial direction in the contact surface (the second sealing surface S2) between the second flange section 64 and the outer circumferential edge section 68a of the heat shield 68. An inner sealing end Si0 (in the present embodiment, the first inner sealing end Si1 corresponds to this), located on a radial outer surface, of the first inner sealing end Si1 and the second inner sealing end Si2 is arranged on the radial outer surface with respect to the rear tongue section 58.

[0024] The inner sealing end Si0 is a radially inner end of the area where the sealing surfaces S1 and S2, formed on both side surfaces of the outer circumferential edge section 68a of the heat shielding plate 68, overlap each other in the radial direction, i.e., the area where the sealing pressure is highest (hereinafter also referred to as a "high sealing pressure area") at the sealing surfaces S1 and S2. Fig. 3 is the area with high sealing pressure indicated by reference symbol Rhs.

[0025] In the present embodiment, a radially outer end (a first sealing outer end So1 (described later)) of the first sealing surface S1 and a radially outer end (a second sealing outer end So2 (described later)) of the second sealing surface S2 are located at essentially the same position in the radial direction. Therefore, the area between the first sealing inner end Si1 and the first sealing outer end So1 is the area Rhs with high sealing pressure.

[0026] According to the present embodiment, since the inner sealing end Si0 (the first inner sealing end Si1) is located on the radial outer side with respect to the rear tongue section 58, the high sealing pressure area Rhs is located in a position radially separated from a section affected by uneven thermal deformation of the rear tongue section 58. Accordingly, the sealing surfaces S1 and S2, formed on both side faces of the outer circumferential edge section 68a of the heat shield plate 68, are prevented from being affected by the uneven thermal deformation of the rear tongue section 58. Therefore, the sealing performance of the sealing surfaces S1 and S2 can be maintained.

[0027] In the present embodiment, the front exhaust gas flow path 56 is located behind the rear exhaust gas flow path 54 with respect to the heat shield plate 68 and is situated in a position separated in the axial direction from the first flange section 62 via the rear exhaust gas flow path 54. Therefore, thermal deformation in the vicinity of the front tongue section 60 hardly affects the first flange section 62. Consequently, in the present embodiment, the thermal deformation of the turbine housing 42 generated in the vicinity of the front tongue section 60 is not taken into account.

[0028] At the in Fig. In the embodiment shown in Figure 3, the rear tongue section 58 is located on the side of the bearing housing 38, and the inner end Si0 is arranged in relation to a lower section D in the vicinity of a partition surface (a partition surface 54a (described later)) of the screw section 44 with the lower section D serving as a reference for comparison on the radial outer side.

[0029] The heat shielding plate 68 has a ring-shaped form and is arranged over the entire area in the circumferential direction so that it surrounds the turbine wheel 40.

[0030] Furthermore, the configuration according to the present embodiment is only applied to the area in the vicinity of the first cross-section in which at least the rear tongue section 58 is formed and does not necessarily have to be applied to the entire area in the circumferential direction.

[0031] Fig. 4, Fig. 5A and Fig. Figure 5B are top views showing some examples of the shape of the rear tongue section 58 when viewed from an upstream side in a flow direction of the exhaust gas.

[0032] In these drawings, reference numeral 54a indicates a partition surface located on the opposite side (the direction side of arrow c) from the partition surfaces of the screw section 44 forming the rear exhaust gas flow path 54, and reference numeral 45a indicates a partition surface facing the rear exhaust gas flow path 54 of a partition 45 that divides the rear exhaust gas flow path 54 and the front exhaust gas flow path 56. Reference numeral 59 indicates a downstream end in the direction of exhaust gas flow e, and reference numeral Tn indicates a reference line that serves as a reference when determining the position in the radial direction of the rear tongue section 58.The position of the reference line Tn is determined from the perspective that it is a section where heat flow increases when the heat contained in the exhaust gas e is transferred to the turbine housing 42 via the rear tongue section 58. In the present embodiment, it can be said that a radial position of the rear tongue section 58 is based on the position of the reference line Tn.

[0033] At a Fig. In the rear tongue section 58a shown in Figure 4, the downstream end 59 has an arc shape, which is located on the furthest downstream side in the direction of flow of the exhaust gas e on both of the partition surfaces 45a and 54a and is located on the furthest upstream side at a midpoint (a central section of the flow) M between both of the partition surfaces 45a and 54a, and the reference line Tn is determined such that it passes through the midpoint M.

[0034] At a Fig. In the rear tongue section 58b shown in Figure 5A, the downstream end 59 is located at the same position in the entire width direction of the rear exhaust gas flow path 54 with respect to the direction of exhaust gas flow e, and the reference line Tn is determined such that it passes through the downstream end 59. That is, the downstream end 59 coincides with the reference line Tn.

[0035] At a Fig. In the rear tongue section 58c shown in Figure 5B, the downstream end 59 has a parabolic shape located at points X and Y on the upstream side in the direction of exhaust gas flow e on both of the partition surfaces 45a and 54a, and at the midpoint M on the downstream side in the direction of exhaust gas flow e. The reference line Tn is determined such that it passes through the most upstream positions (points X and Y) of the rear tongue section 58c. That is, the reference line Tn is a line with a direction perpendicular to the direction of exhaust gas flow e (the latitude direction of the rear exhaust gas flow path 54) and passes through the most upstream position in the direction of exhaust gas flow e of the downstream end 59.

[0036] Fig. Figure 6 is a vertical sectional view (the first cross-section) showing an enlarged portion of an exhaust gas turbine section 34b according to another embodiment. Fig. 6 includes a fastening element 66a according to one embodiment, a base section 70 arranged on an outer circumferential side of the first flange section 62 and the second flange section 64, a first fastening section 72 extending from the base section 70 to a radial inside along a rear surface 62a of the first flange section 62, and a second fastening section 74 extending from the base section 70 to the radial inside along a rear surface 64a of the second flange section 64.

[0037] In the Fig. In the cross-section shown in Figure 6 (the first cross-section), a point So1 indicates an outermost position (a first sealing end) in the radial direction in the contact surface (the first sealing surface S1) between the first flange section 62 and the outer circumferential edge section 68a of the heat shielding plate 68. Furthermore, in the same drawing, a point So2 indicates an outermost position (a second sealing end) in the radial direction in the contact surface (the second sealing surface S2) between the second flange section 64 and the outer circumferential edge section 68a of the heat shielding plate 68.

[0038] The outer sealing end located on the inside in the radial direction of the first outer sealing end So1 and the second outer sealing end So2 is positioned such that it is a sealing outer end So0. In the present embodiment, since the first outer sealing end So1 and the second outer sealing end So2 are located in substantially the same position in the radial direction, either the first outer sealing end So1 or the second outer sealing end So2 corresponds to the sealing outer end So0.

[0039] Furthermore, there is in Fig. Reference numeral Ti1 indicates an innermost position (a first inner mounting end) in the radial direction in a contact surface (a first pressurized surface Ps1) between the first mounting section 72 and the rear surface 62a of the first flange section 62. Reference numeral Ti2 indicates an innermost position (a second inner mounting end) in the radial direction in a contact surface (a second pressurized surface Ps2) between the second mounting section 74 and the rear surface 64a of the second flange section 64.

[0040] In a case where the mounting inner end, which is located on the outside in the radial direction, is set by the first mounting inner end Ti1 and the second mounting inner end Ti2 such that it is a mounting inner end Ti0, the sealing outer end So0 is arranged on the radial inside with respect to the mounting inner end Ti0.

[0041] The inner fastening end Ti0 is an inner end of a radial region (hereinafter also referred to as a "high fastening pressure region") in which the fastening force is exerted on the first flange section 62 and the second flange section 64 by both the first fastening section 72 and the second fastening section 74. Fig. 6 is the area with high fastening pressure, indicated by reference symbol Rht.

[0042] At the in Fig. In the embodiment shown in Figure 6, since the first inner mounting end Ti1 and the second inner mounting end Ti2 are located at substantially the same position in the radial direction, either the first inner mounting end Ti1 or the second inner mounting end Ti2 constitutes the inner mounting end Ti0. Here, "same position in the radial direction" means a position where the distance from the central axis O along a straight line perpendicular to the central axis O of the rotating shaft 36 is equal. Furthermore, since a radially outer end (a first outer mounting end To1 (described later)) of the first pressure-bearing surface Ps1 is located on the inside in the radial direction with respect to a radially outer end (a second outer mounting end To2 (described later)) of the second pressure-bearing surface Ps2, the first pressure-bearing surface Ps1 forms the high-pressure mounting region Rht.

[0043] According to the present embodiment, the outer sealing end So0 (the first outer sealing end So1 or the second outer sealing end So2, the radially outer end of the high-pressure sealing region Rhs) is located on the radial inner side with respect to the inner mounting end Ti0 (the inner end of the high-pressure mounting region Rht). Therefore, the high-pressure sealing region Rhs is located in a position that is radially inwardly separated from the high-pressure mounting region Rht, in which both of the flange sections 62 and 64 absorb the greatest fastening force from the fastening element 66a.Accordingly, even in a case where the fastening force of the fastening element 66a is pre-tensioned in the circumferential direction of both of the flange sections 62 and 64, the sealing performance of these sealing surfaces can be ensured, since the pre-tension in the circumferential direction of the fastening force exerted on both of the sealing surfaces S1 and S2 is mitigated.

[0044] In one embodiment, the base section 70 is provided in substantially the entire area in the circumferential direction such that it surrounds the first flange section 62 and the second flange section 64 from the outer circumferential side.

[0045] In one embodiment, the base section 70 has a connection (opening) formed in a portion of it in the circumferential direction, and a flange section (not shown) is provided at each of the two end sections of the base section 70 in the circumferential direction, with the connection inserted between them. The flange sections project towards the radial outer surface and are arranged so that they face each other. The flange sections are brought close to each other by a fastening tool, such as a bolt, so that the fastening element 66 fastens the first flange section 62 and the second flange section 64 together.

[0046] In one embodiment, the first fastening section 72 and the second fastening section 74 of the fastening element 66 need not necessarily be provided over the entire circumference in the circumferential direction. It is possible that the fastening sections are provided only in the vicinity of the first cross-section in which at least the rear tongue section 58 is present.

[0047] At the in Fig. In the embodiment shown in Figure 6, a base section 70a of the fastening element 66a has an extension section that extends linearly along the axis direction. Furthermore, the rear surface 62a of the first flange section 62 and the rear surface 64a of the second flange section 64 are inclined surfaces that are inclined in a direction in which the rear surface 62a and the rear surface 64a are separated from each other towards the radial inside. The first fastening section 72 extends towards the radial inside along the rear surface 62a of the first flange section 62, and the second fastening section 74 extends towards the radial inside along the rear surface 64a of the second flange section 64.

[0048] According to this embodiment, the connection (opening) formed in a portion of the base section 70 in the circumferential direction is narrowed by using a fastening tool, such as a bolt, so that the first fastening section 72 slides on the rear surface 62a of the first flange section 62 towards the radial inner side, and the second fastening section 74 slides on the rear surface 64a of the second flange section 64 towards the radial inner side when the diameter of the base section 70 is reduced. Therefore, a fastening force can be efficiently applied to the first flange section 62 and the second flange section 64, and the fastening force of the fastener 66 can be prevented from becoming uneven in the circumferential direction.

[0049] In another embodiment, as in Fig. Figure 7 shows a fastening element 66b in accordance with the shapes of the tip sections of the first flange section 62 and the second flange section 64. The fastening element 66b has a base section 70b that does not have an extension section along the axis direction. The fastening element 66b has an overall V-shape.

[0050] Furthermore, in another embodiment (not shown), the fastening element comprises a base section extending along the axis direction, and the first fastening section and the second fastening section extending from both end sections of the base section along a direction perpendicular to the axis direction toward the radial inside. According to this embodiment, since the first fastening section and the second fastening section are not shaped to be located along the rear surfaces 62a and 64a of both flange sections 62 and 64, it is not necessary to machine the angles of the first fastening section and the second fastening section with respect to the base section to match the rear surfaces 62a and 64a of both flange sections. Therefore, the machining is simplified.

[0051] In one embodiment, as in Fig. Figure 6 shows that on one flange section, at least one inner projection 80 is formed on the radial outer side of the outer circumferential edge section 68a of the heat shielding plate 68, projecting towards the other flange section of both flange sections 62 and 64, and on the other flange section, at least one outer projection 82 is formed, the inner circumferential surface of which comes into contact with an outer circumferential surface of the inner projection 80, on the radial outer side of the inner projection 80.

[0052] According to the present embodiment, the inner projection 80 and the outer projection 82 are provided on the radial outer surface of the outer circumferential edge section 68a of the heat shield plate 68, and a contact surface is provided where an outer circumferential surface 80a of the inner projection 80 and an inner circumferential surface 82a of the outer projection 82 come into contact with each other. Since the contact surface forms a sealing surface, the sealing performance can be further improved. In addition, the inner projection 80 and the outer projection 82 are provided so that axial misalignment between the turbine housing 42 and the bearing housing 38 can be prevented.

[0053] At the in Fig. In the embodiment shown in Figure 6, the inner projection 80 extends from the second flange section 64 towards the first flange section 62, and the outer projection 82 extends from the first flange section 62 towards the second flange section 64.

[0054] In another embodiment, the inner projection 80 can be formed such that it projects from the first flange section 62 to the second flange section 64, and the outer projection 82 can be formed such that it projects from the second flange section 64 to the first flange section 62.

[0055] At the in Fig. In the embodiment shown in Figure 6, the inner projection 80 and the outer projection 82 each have a rectangular cross-section in the first cross-section. Furthermore, the projection length of the inner projection 80 has a dimension that is essentially equal to the thickness of the outer circumferential edge section 68a of the heat shielding plate 68. However, the inner projection 80 and the outer projection 82 may each have a cross-section other than a rectangular shape in the first cross-section.

[0056] In one embodiment, as in Fig. As shown in Figure 6, the outer projection 82 is formed in the first flange section 62. According to this embodiment, since the outer projection 82 is formed in the first flange section 62 and an outer circumferential surface of the outer projection 82 is an open surface, the thermal deformation of the outer projection 82 due to the heat transferred from the side of the rear exhaust gas flow path 54 and the front exhaust gas flow path 56 to the first flange section 62 is hardly transferred to the side of the second flange section 64. Therefore, it is possible to suppress a decrease in the sealing performance of the second sealing surface S2 on the side of the second flange section 64 due to the thermal deformation of the first flange section 62.

[0057] At the in Fig. In the embodiment shown in Figure 6, a projection 65 is formed such that it extends radially outwards from an outer circumferential side of the second flange section 64. The projection 65 has an end surface 65b that faces an end surface 82b of the outer projection 82. The second pressure-bearing surface Ps2 can be widened towards the radial outer side by forming the projection 65. Accordingly, the fastening force can be increased by the second fastening section 74.

[0058] In one embodiment, the in Fig. In the cross-section shown in Figure 6 (the first cross-section), the radial length of the area (the first sealing surface S1) between the first outer sealing end So1 and the first inner sealing end Si1 is smaller than the radial length of the area (the second sealing surface S2) between the second outer sealing end So2 and the second inner sealing end Si2 (S1 < S2).

[0059] According to the present embodiment, since the radial length of the first sealing surface S1 is smaller than the radial length of the second sealing surface S2, the amount of heat transferred from the first flange section 62 to the bearing housing 38 via the outer circumferential edge section 68a of the heat shield 68 can be suppressed. Accordingly, since a temperature rise and thermal deformation of the bearing housing 38 are suppressed, a decrease in the sealing performance of the second sealing surface S2 can be suppressed. Furthermore, since the thermal stress generated in the bearing housing 38 due to the temperature rise can also be suppressed, the service life of the bearing housing 38 is also improved.Furthermore, the area of ​​the first sealing surface S1 is reduced, so that the contact surface pressure exerted on the first sealing surface S1 per unit area is increased, and thus the sealing performance of the first sealing surface S1 can be improved.

[0060] Fig. Figure 8 is a vertical sectional view (the first cross-section) showing an exhaust gas turbine section 34c according to yet another embodiment. Fig. 8. Point To1 indicates an outermost position (a first mounting outer end) in the radial direction in a contact surface (a first pressurized surface Ps1) between the first mounting section 72 and the rear surface 62a of the first flange section 62. Point To2 indicates an outermost position (a second mounting outer end) in the radial direction in a contact surface (a second pressurized surface Ps2) between the second mounting section 74 and the rear surface 64a of the second flange section 64. The mounting outer end located on the inside in the radial direction of the first mounting outer end To1 and the second mounting outer end To2 is positioned such that it is a mounting outer end To0 (in the present embodiment, the second mounting outer end To2 corresponds to the mounting outer end To0).In this case, for a fastening area (a high fastening pressure area Rht) between the inner fastening end Ti0 and the outer fastening end To0 in the radial direction, the average wall thickness At2 of the second flange section 64 in the axial direction is less than the average wall thickness At1 of the first flange section 62 in the axial direction (At2 < At1). The inner fastening end Ti0 is formed in the first flange section 62. That is, the second inner fastening end Ti2 is located on the radial inside with respect to the first inner fastening end Ti1, and the second pressurized area Ps2 on the side of the second fastening section 74 extends to the radial inside with respect to the first pressurized area Ps1 on the side of the first fastening section 72.

[0061] According to the present embodiment, since (the average wall thickness At2 of the second flange section 64) is less than (the average wall thickness At1 of the first flange section 62), when the fastening force of the fastener 66 is exerted on both flange sections 62 and 64, the second flange section 64 is deformed more. Therefore, the second sealing surface S2, formed between the second flange section 64 and the outer circumferential edge section 68a of the heat shield 68, is subjected to a slightly uneven radial load. However, since the second pressurized surface Ps2 extends towards the radial inner side of the second flange section 64, the fastening force of the fastener 66 is exerted on the radial inner area, which is further than that of the first flange section 62.Therefore, the uneven load in the radial direction applied to the second sealing surface S2 on the side of the second flange section 64 is balanced, so that an essentially uniform load L2 is obtained, and the sealing performance of the second sealing surface S2 on the side of the second flange section 64 is maintained.

[0062] Since the first pressurized area Ps1 of the first flange section 62 does not extend to the radial inner area like the second pressurized area Ps2, the fastening force of the fastener 66 does not reach the radial inner area as it does in the second flange section 64. Therefore, a non-uniform radial load is readily applied to the first sealing surface S1. However, since the average wall thickness At1 of the first flange section 62 is greater than the average wall thickness At2 of the second flange section 64, deformation is less likely to occur than in the second flange section 64. Therefore, such a non-uniform radial load is not applied to the first sealing surface S1 on the side of the first flange section 62, and a uniform load L1 is applied to the first sealing surface S1.Since the loads applied to the sealing surfaces S1 and S2 on the side of first flange section 62 and the side of second flange section 64 are averaged in the radial direction, the sealing performance can be maintained in this way.

[0063] At the in Fig. In the embodiment shown in Figure 8, the average wall thickness At1 of the first flange section 62 is greater than the average wall thickness At2 of the second flange section 64, and the inner mounting end Ti0 is located in the first flange section 62. However, in another embodiment, the average wall thickness At2 of the second flange section 64 can be greater than the average wall thickness At1 of the first flange section 62, and the inner mounting end Ti0 can be located in the second flange section 64.

[0064] In one embodiment, as in Fig. Figure 3 shows a distance Ra along the radial direction between the center of the rotating shaft 36 and the rear tongue section 58 and a distance Rb along the radial direction between the central axis O of the rotating shaft 36 and the inner end of the seal Si0 configured such that they satisfy a relationship of 1.1Ra ≤ Rb.

[0065] According to this embodiment, since each of the sealing surfaces S1 and S2 is sufficiently separated from the rear tongue section 58 to the radial outer surface, the sealing surfaces S1 and S2 are essentially not affected by the uneven thermal deformation of the rear tongue section 58. Therefore, the sealing performance of the sealing surfaces S1 and S2 can be maintained.

[0066] In one embodiment, the in Fig.In the cross-section shown in Figure 6 (the first cross-section), the turbine casing 42 has an extension section 90 that extends from an outer circumferential surface of the screw section 44 to the first flange section 62 along the axis direction. In the first cross-section, a wall thickness t1 of a section 92 with minimum wall thickness, where the wall thickness in the radial direction of the extension section 90 is the minimum wall thickness, and a distance t2 along the axis direction between the section 92 with minimum wall thickness and the first inner end of the seal Si1 are configured such that they satisfy a relationship of t1 ≤ t2. When the heat flux generated by the heat transferred from the exhaust gas e to the turbine casing 42 flows through the extension section 90, the heat flux with the highest density per unit area flows through the section 92 with minimum wall thickness.

[0067] According to the present embodiment, since the relationship t1 ≤ t2 exists and the first sealing surface S1 is separated from the section 92 with minimum wall thickness by a certain distance, it is less likely that the first sealing surface S1 will be affected by the uneven thermal deformation of the rear tongue section 58. Therefore, the sealing performance of the first sealing surface S1 can be maintained.

[0068] The contents described for each of the embodiments described above are understood, for example, as follows.

[0069] (1) An exhaust gas turbine according to one aspect comprises: a rotating shaft (36); a turbine wheel (40) mounted on one end of the rotating shaft (36); a turbine housing (42) accommodating the turbine wheel (40) and in which a worm gear section (44) introducing an exhaust gas (e) to the turbine wheel (40) is formed on an outer circumferential side of the turbine wheel (40); a bearing housing (38) accommodating a bearing (52) supporting the rotating shaft (36) and provided adjacent to the turbine housing (42); a fastening element (66) for joining together a first flange section (62) of the turbine housing (42) and a second flange section (64) of the bearing housing (38); and a heat shielding plate (68) arranged between the turbine housing (42) and the bearing housing (38) and having an outer circumferential edge section (68a) clamped between the first flange section (62) and the second flange section (64),wherein, in a first cross-section along an axis direction of the rotating shaft (36) passing through a center (O) of the rotating shaft (36) and a tongue section (58) of the turbine housing (42), in a case where an innermost position in a radial direction of the rotating shaft (36) in a contact surface (S1) between the first flange section (62) and the outer circumferential edge section (68a) of the heat shield (68) is set such that it is a first inner sealing end (Si1), an innermost position in the radial direction in a contact surface (S2) between the second flange section (64) and the outer circumferential edge section (68a) of the heat shield (68) is set such that it is a second inner sealing end (Si2), and a inner sealing end located on an outer surface in the radial direction is set such that it is a second inner sealing end (Si2). a sealing inner end (Si0) is,the inner end of the seal (Si0) is arranged on an outer side in the radial direction with respect to the tongue section (58).

[0070] According to such a configuration, the inner sealing end (Si0) (an inner end of a radial area in which each of the sealing surfaces (S1, S2) is formed on each of the two surfaces of the outer circumferential edge section (68a) of the heat shielding plate (68) between the outer circumferential edge section (68a) of the heat shielding plate (68) and each of the flange sections (62, 64)), which is located on the outside in the radial direction of the rotating shaft (36), is arranged by the first inner sealing end (Si1) and the second inner sealing end (Si2) on the radial outside in relation to the tongue section (58).Therefore, the sealing surfaces (S1, S2) are formed on both faces of the outer circumferential edge section (68a) of the heat shield (68), and the radial area where the sealing performance is most effective is located at a position separated from the radial outer side of the section affected by the uneven thermal deformation of the tongue section (58). Accordingly, since the sealing surfaces (S1, S2) formed on the outer circumferential edge section (68a) of the heat shield (68) are prevented from being affected by the uneven thermal deformation of the tongue section (58), the sealing performance of the heat shield (68) can be maintained.

[0071] (2) In an exhaust gas turbine according to a further aspect, in the exhaust gas turbine according to (1) above, the fastening element (66) comprises a base section (70) arranged on an outer circumferential side of the first flange section (62) and the second flange section (64), a first fastening section (72) extending from the base section (70) to an inner side in the radial direction along a rear surface (62a) of the first flange section (62), and a second fastening section (74) extending from the base section (70) to the inner side in the radial direction along a rear surface (64a) of the second flange section (64), and in the first cross-section, in a case where an outermost position in the radial direction in the contact surface (S1) between the first flange section (62) and the outer circumferential edge section (68a) of the heat shield plate (68) is set such that it is a first sealing outer end (So1),an outermost position in the radial direction in the contact surface (S2) between the second flange section (64) and the outer circumferential edge section (68a) of the heat shield plate (68) is set such that it is a second sealing outer end (So2); a sealing outer end located on the inside in the radial direction of the first sealing outer end (So1) and the second sealing outer end (So2) is set such that it is a sealing outer end (So0); an innermost position in the radial direction in a contact surface (S1) between the first mounting section (72) and the rear surface (62a) of the first flange section (62) is set such that it is a first mounting inner end (Ti1); an innermost position in the radial direction in a contact surface (S2) between the second mounting section (74) and the rear surface (64a) of the second flange section (64) is set such that it is a second mounting inner end (Ti2) is,and a mounting inner end, which is located on the outside in the radial direction, is set from the first mounting inner end (Ti1) and the second mounting inner end (Ti2) such that it is a mounting inner end (Ti0), the sealing outer end (So0) arranged on an inside in relation to the mounting inner end (Ti0) in the radial direction.

[0072] According to such a configuration, the sealing outer end (So0) (an outer end in the radial region where each of the sealing surfaces (S1, S2) is formed on each of the two surfaces of the outer circumferential edge section (68a) of the heat shielding plate (68) between the outer circumferential edge section (68a) of the heat shielding plate (68) and both of the flange sections (62, 64)) is located on the radial inner side with respect to the fastening inner end (Ti0) (the inner end in the radial region where the fastening force is exerted on each of the flange sections (62, 64) by the first fastening section (72) and the second fastening section (74) respectively).Therefore, the sealing area (Rhs), where the sealing performance of the heat shield plate (68) is most pronounced in the radial direction, is located in a position separate from the area (Rht) where both flange sections (62, 64) absorb the greatest fastening force from the fastener (66). Accordingly, even if the fastening force of the fastener (66) exerted on both flange sections (62, 64) is preloaded in the circumferential direction of the rotating shaft (36), the sealing performance of both sealing surfaces (S1, S2) is ensured because the preload in the circumferential direction of the fastening force exerted on the sealing area (Rhs) is mitigated.

[0073] (3) In an exhaust gas turbine according to yet another aspect, in the exhaust gas turbine according to (1) or (2) above, at least one inner projection (80) is formed on a flange section of the first flange section (62) and the second flange section (64), projecting towards the other flange section of the first flange section (62) and the second flange section (64), on an outside of the outer circumferential edge section (68a) of the heat shielding plate (68) in the radial direction, and at least one outer projection (82) is formed on the other flange section, having an inner circumferential surface (82a) that comes into contact with an outer circumferential surface (80a) of the inner projection (80) in the radial direction.

[0074] According to this configuration, the inner projection (80) and the outer projection (82) are formed on the radial outer surface of the outer circumferential edge section (68a) of the heat shield plate (68), and the sealing performance can be improved due to the presence of these concave and convex sections. Therefore, the sealing performance between the first flange section (62) and the second flange section (64) is improved. Furthermore, since the turbine housing (42) and the bearing housing (38) are positioned radially by the inner projection (80) and the outer projection (82), axial misalignment between these housings is prevented.

[0075] (4) In an exhaust gas turbine according to yet another aspect, in the exhaust gas turbine according to (3) above, at least one outer projection (82) is formed in the first flange section (62).

[0076] According to such a configuration, since at least one outer projection (82) is formed in the first flange section (62), the bearing housing (38) is not affected by the thermal deformation of the outer projection (82), even if the outer projection (82) is thermally deformed due to the heat of the exhaust gas (e). Therefore, the influence of the thermal deformation of the turbine housing (42) on the bearing housing (38) is mitigated, thus suppressing a decrease in the sealing performance of the sealing surface (S2) formed between the second flange section (64) on the side of the bearing housing (38) and the heat shield (68).

[0077] (5) In an exhaust gas turbine according to yet another aspect, in the exhaust gas turbine according to one of the above (1) to (4), in the first cross-section, the length of the contact area (S1) between the first flange section (62) and the outer circumferential edge section (68a) of the heat shielding plate (68) is smaller than the length of the contact area (S2) between the second flange section (64) and the outer circumferential edge section (68a) of the heat shielding plate (68).

[0078] According to this configuration, since the contact area (S1) between the first flange section (62) and the outer circumferential edge section (68a) of the heat shield (68) is smaller than the contact area (S2) between the second flange section (64) and the outer circumferential edge section (68a) of the heat shield (68), heat transfer from the first flange section (62) to the bearing housing (38) via the outer circumferential edge section (68a) of the heat shield (68) is suppressed. Accordingly, since the temperature rise and thermal deformation of the bearing housing (38) are suppressed, a decrease in sealing performance between the heat shield (68) and the second flange section (64) can be suppressed.Furthermore, since the thermal stress generated in the bearing housing (38) due to the temperature increase is also suppressed, the service life of the bearing housing (38) is also improved.

[0079] (6) In the case of an exhaust gas turbine according to yet another aspect, in the case of the first cross-section, in a case where an outermost position in the radial direction in a contact surface (Ps1) between the first mounting section (72) and a rear surface (62a) of the first flange section (62) is set such that it is a first mounting outer end (To1), an outermost position in the radial direction in a contact surface (Ps2) between the second mounting section (74) and a rear surface (64a) of the second flange section (64) is set such that it is a second mounting outer end (To2), and a mounting outer end located on the inside in the radial direction of the first mounting outer end (To1) and the second mounting outer end (To2) is set such that it is a mounting outer end (To0),In a fastening area (Rht) between the inner fastening end (Ti0) and the outer fastening end (To0), the average value (At) of a wall thickness in the axial direction (O) of one flange section of the first flange section (62) and the second flange section (64) is less than the average value (At) of a wall thickness in the axial direction (O) of the other flange section of the first flange section (62) and the second flange section (64), and the inner fastening end (Ti0) is formed in the other flange section.

[0080] According to such a configuration, in the fastening area (Rht) (the area where the fastening force is exerted radially on the outer circumferential edge section (68a) of the heat shield (68) from both sides of the first fastening section (72) and the second fastening section (74)), since the average wall thickness (At) in the axial direction of one flange section of the first flange section (62) and the second flange section (64) is smaller than the average wall thickness (At) of the other flange section, one flange section deforms more than the other flange section due to the fastening force of the fastener (66). Therefore, it is likely that an uneven load in the radial direction is applied to the sealing surface formed between one flange section and the outer circumferential edge section (68a) of the heat shield (68).Since the inner fastening end (Ti0) is formed in the other flange section, the fastening force exerted on one flange section reaches the radial inner side with respect to the other flange section. Therefore, the uneven load in the radial direction applied to the sealing surface on one side of the flange section is balanced, and the sealing performance of the sealing surface on that side of the flange section is maintained.

[0081] In contrast, since the other flange section is formed with the inner fastening end (Ti0), the radially inner end of the area where the fastening force of the fastener (66) is exerted on the other flange section side is located outside the radially inner end of the area where the fastening force of the fastener (66) is exerted on one flange section. Therefore, the fastener (66) readily applies a non-uniform load in the radial direction to the sealing surface formed between the other flange section and the outer circumferential edge section (68a) of the heat shield (68).However, since the average wall thickness (At) of the other flange section in the axial direction is greater than the average wall thickness (At) of one flange section, deformation of the other flange section due to the fastening force exerted by the fastener (66) is less likely than in one flange section. Therefore, the sealing performance of the sealing surface on the other side of the flange section is ensured.

[0082] (7) In the case of an exhaust gas turbine according to yet another aspect, in the case of the exhaust gas turbine according to one of the above (1) to (6), in the first cross-section, a distance Ra in the radial direction between the center of the rotating shaft (36) and the tongue section (58) and a distance Rb in the radial direction between the center (O) of the rotating shaft (36) and the inner end of the seal (Si0) satisfy a relationship of 1.1Ra ≤ Rb.

[0083] According to such a configuration, since each of the sealing surfaces (S1, S2) formed between the first flange section (62) and the second flange section (64) and the outer circumferential edge section (68a) of the heat shield plate (68) is located at a position sufficiently separated radially from the tongue section (58), the sealing surfaces (S1, S2) are essentially not affected by the non-uniform thermal deformation of the tongue section (58). Therefore, the sealing performance of the sealing surfaces (S1, S2) can be maintained.

[0084] (8) In an exhaust gas turbine according to yet another aspect, in the exhaust gas turbine according to one of the above (1) to (7), the turbine casing (42) includes an extension section (90) which extends from an outer circumferential surface of the screw section (44) to the first flange section (62) along the axis direction (O), and in the first cross-section, a wall thickness t1 of a section (92) with minimum wall thickness, where a wall thickness in the radial direction of the extension section (90) is a minimum wall thickness, and a distance t2 along the axis direction (O) between the section (92) with minimum wall thickness and the first inner end of the seal (Si1) satisfy a relationship of t1 ≤ t2.

[0085] The heat flux generated in the turbine housing (42) due to the heat transferred from the exhaust gas (e) to the turbine housing (42) exhibits the highest density per unit area in the section (92) with minimum wall thickness. According to the configuration above, since the distance t2 in the axial direction between the section (92) with minimum wall thickness and the second inner gasket end (Si2) is equal to or greater than the wall thickness t1 of the section (92) with minimum wall thickness, the sealing area (S1) formed between the first flange section (62) and the outer circumferential edge section (68a) of the heat shield plate (68) is less likely to be affected by the non-uniform thermal deformation of the tongue section (58), and the sealing performance can be maintained.

[0086] (9) A supercharger according to yet another aspect further comprises: the exhaust turbine (34) according to any of the above (1) to (8); a compressor wheel (32b) which is mounted on the other end of the rotating shaft (36) via the bearing housing (38) in relation to the turbine wheel (40); and a compressor housing (32a) which accommodates the compressor wheel (32b).

[0087] According to such a configuration, since the exhaust gas turbine (34) is provided according to one of the above (1) to (8), even if uneven thermal deformation occurs in the vicinity of the tongue section (58) formed in the turbine housing (42) through which the exhaust gas (e) flows, due to the heat of the exhaust gas (e), the sealing performance of each of the sealing surfaces (S1, S2) formed between the first flange section (62) of the turbine housing (42) and the second flange section (64) of the bearing housing (38) and the heat shielding plate (68) can be maintained at a high level. Reference symbol list 10 Motor 12a, 12b, 12c, 12d cylinders 14 Main engine body 16 Air supply pipe 18 air supply distributors 20 exhaust manifolds 22 Exhaust pipe 30 chargers 32 Compressor section 32a Compressor housing 32b Compressor wheel 34 (34a, 34b, 34c) Exhaust turbine section 36 Rotary shaft 38 bearing housings 40 Turbine wheel 42 Turbine housing 44 snail section 45 partition wall 45a Partition wall area 46 Exhaust gas inlet section 48 shovels 50 Exhaust gas inlet channel 52 warehouses 54 rear exhaust flow path 56 front exhaust flow path 54a Partition wall area 58 posterior tongue section 59 downstream end 60 anterior tongue section 62 first flange section 62a Rear surface 64 second flange section 64a Back surface 65 lead 65b End area 66 (66a, 66b, 66c) Fastening element 68 Heat shielding plate 68a Outer circumferential edge section 70 (70a, 70b) Basic section 72 first fastening section 74 second fastening section 80 inner lead 80a External perimeter area 82 outside lead 82a Inner circumferential area 82b End surface 90 Extension section Section 92 with minimum wall thickness L1, L2 Last D lower section of tongue section M Center O Central axis PS1 first pressurization surface PS2 second pressurization surface Rhs area with high sealing pressure Rht area with high fastening pressure S1 first sealing surface S2 second sealing surface Si1 first inner seal end Si2 second inner seal end Si0 inner seal end So1 first outer seal end So2 second outer seal end So0 Seal outer end Ti1 first inner fastening end Ti2 second inner mounting end Ti0 mounting inner end Tn reference line of tongue section To1 first outer mounting end To2 second mounting outer end To0 Mounting outer end a air for fuel QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2009-167971

[0003] JP 2012-117483

[0003]

Claims

[1] Exhaust gas turbine, comprising: a rotating shaft; a turbine wheel mounted on one end of the rotating shaft; a turbine housing that houses the turbine wheel and in which a worm portion that introduces an exhaust gas to the turbine wheel is formed on an outer peripheral side of the turbine wheel; a bearing housing that houses a bearing that supports the rotating shaft and that is provided adjacent to the turbine housing; a fastening element for fastening a first flange portion of the turbine housing and a second flange portion of the bearing housing together; and a heat shielding plate disposed between the turbine housing and the bearing housing and having an outer peripheral edge portion sandwiched between the first flange portion and the second flange portion, wherein, in a first cross section taken along an axis line direction of the rotary shaft and passing through a center of the rotary shaft and a tongue portion of the turbine housing, in a case where an innermost position in a radial direction of the rotary shaft in a contact surface between the first flange portion and the outer peripheral edge portion of the heat shielding plate is set to be a first seal inner end, an innermost position in the radial direction in a contact surface between the second flange portion and the outer peripheral edge portion of the heat shielding plate is set to be a second seal inner end, and a seal inner end located on an outer side in the radial direction between the first seal inner end and the second seal inner end is set to be a seal inner end, the seal inner end is located on an outer side in the radial direction with respect to the tongue portion. [2] An exhaust gas turbine according to claim 1, wherein the fastening element includes: a base portion disposed on an outer peripheral side of the first flange portion and the second flange portion, a first fastening portion extending from the base portion to an inner side in the radial direction along a rear surface of the first flange portion, and a second fixing portion extending from the base portion to the inside in the radial direction along a rear surface of the second flange portion, and in the first cross section, in a case where an outermost position in the radial direction in the contact surface between the first flange portion and the outer peripheral edge portion of the heat-shielding plate is set to be a first seal outer end, an outermost position in the radial direction in the contact surface between the second flange portion and the outer peripheral edge portion of the heat-shielding plate is set to be a second seal outer end, a seal outer end located on the inner side in the radial direction of the first seal outer end and the second seal outer end is set to be a seal outer end, an innermost position in the radial direction in a contact surface between the first fastening portion and the back surface of the first flange portion is set to be a first fastening inner end,an innermost position in the radial direction in a contact surface between the second fastening portion and the back surface of the second flange portion is set to be a second fastening inner end, and a fastening inner end located on the outer side in the radial direction of the first fastening inner end and the second fastening inner end is set to be a fastening inner end, the seal outer end is arranged on an inner side in the radial direction with respect to the fastening inner end. [3] The exhaust gas turbine according to claim 1 or 2, wherein at one flange portion of the first flange portion and the second flange portion, at least one inner projection projecting toward the other of the first flange portion and the second flange portion is formed on an outer side of the outer peripheral edge portion of the heat shielding plate in the radial direction, and at the other flange portion, at least one outer projection having an inner peripheral surface coming into contact with an outer peripheral surface of the inner projection is formed on an outer side of the inner projection in the radial direction. [4] The exhaust gas turbine of claim 3, wherein the at least one outer projection is formed in the first flange portion. [5] The exhaust gas turbine according to any one of claims 1 to 4, wherein, in the first cross section, a length of the contact area between the first flange portion and the outer peripheral edge portion of the heat shielding plate is smaller than a length of the contact area between the second flange portion and the outer peripheral edge portion of the heat shielding plate. [6] The exhaust gas turbine according to claim 2, wherein, in the first cross section, in a case where an outermost position in the radial direction in a contact surface between the first fixing portion and a rear surface of the first flange portion is set to be a first fixing outer end, an outermost position in the radial direction in a contact surface between the second fixing portion and a rear surface of the second flange portion is set to be a second fixing outer end, and a fixing outer end located on the inner side in the radial direction of the first fixing outer end and the second fixing outer end is set to be a fixing outer end, in a fastening region between the fastening inner end and the fastening outer end in the radial direction, an average value of a wall thickness in the axial line direction of one flange portion of the first flange portion and the second flange portion is smaller than an average value of a wall thickness in the axial line direction of the other flange portion of the first flange portion and the second flange portion, and the fastening inner end is formed in the other flange section. [7] The exhaust gas turbine according to any one of claims 1 to 6, wherein, in the first cross section, a distance Ra in the radial direction between the center of the rotary shaft and the tongue portion and a distance Rb in the radial direction between the center of the rotary shaft and the seal inner end satisfy a relationship of 1.1Ra ≤ Rb. [8] Exhaust gas turbine according to one of claims 1 to 7, wherein the turbine housing includes an extension portion extending from an outer peripheral surface of the screw portion toward the first flange portion along the axis line direction, and in the first cross section, a wall thickness t1 of a minimum wall thickness portion in which a wall thickness in the radial direction of the extension portion is a minimum wall thickness, and a distance t2 along the axis line direction between the minimum wall thickness portion and the first gasket inner end satisfy a relationship of t1 ≤ t2. [9] Charger, further comprising: the exhaust gas turbine according to one of claims 1 to 8; a compressor wheel mounted with respect to the turbine wheel via the bearing housing on the other end side of the rotating shaft; and a compressor housing that houses the compressor wheel.

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