TURBINE WHEEL AND TURBOCHARGER

Abstract

A turbine wheel according to the present invention is provided within a turbine housing of a supercharger. This turbine wheel includes a hub and a plurality of blades. The hub is coupled to a rotating shaft of the supercharger. The plurality of blades are provided on the hub at intervals in the circumferential direction with respect to the rotating shaft. The plurality of blades includes at least one first blade and at least one second blade. The shape of the first blade and the shape of the second blade differ from each other.

Description

Technical area

[0001] The present disclosure relates to a turbine wheel and a turbocharger. State of the art

[0002] A turbocharger is known for use in an internal combustion engine of a large ship or automobile. The turbocharger rotates a turbine impeller using a flow of exhaust gas generated in an internal combustion engine and rotates a compressor impeller arranged coaxially with the turbine impeller. The power of the internal combustion engine is increased by supplying high-pressure air from the compressor impeller to a combustion chamber.

[0003] For example, a turbine impeller of a turbocharger disclosed in PTL 1 is configured to rotate using a flow of exhaust gas flowing through a scroll flow path formed at a turbine housing. The exhaust gas that has passed through the turbine impeller is discharged to the outside via a gas outlet portion formed at the turbine housing. Citation listPatent literature

[0004] [PTL 1] Japanese Patent No. 6796214 Summary of the invention Technical problem

[0005] Abnormal noise may be generated when the turbine runner rotates. For example, in a case where a blade of the turbine runner interferes with a vortex generated at a tongue portion formed on an inner wall surface of the turbine casing, or in a case where a blade tip of a subsequent turbine runner interferes with a vortex generated at a blade tip of a preceding turbine runner, abnormal noise is generated. According to the inventor's knowledge, such abnormal noise tends to be significantly generated when a specific relationship is established between the number of blades and the rotation frequency of the turbine runner (or the frequency obtained by multiplying the rotation frequency by an integer of 2 or more).

[0006] An object of the present disclosure is to provide a turbine wheel and a turbocharger in which the generation of abnormal noise can be suppressed. Solution to the problem

[0007] According to at least one embodiment of the present disclosure, there is provided a turbine wheel provided in a turbine housing of a turbocharger, the turbine wheel comprising: a hub connected to a rotating shaft of the turbocharger; and a plurality of blades provided on the hub at intervals in a circumferential direction with respect to the rotating shaft, the plurality of blades comprising at least one first blade and at least one second blade having a shape different from that of the first blade.

[0008] According to at least one embodiment of the present disclosure, there is provided a turbocharger comprising: the turbine wheel according to the above-described embodiment; and a turbine housing accommodating the turbine wheel, the turbine housing including a scroll part in which a scroll flow path for allowing exhaust gas to flow in the circumferential direction is formed on an outer side in a radial direction with respect to the turbine wheel, and a tongue part formed on an inner peripheral side of the scroll flow path. Advantageous effects of the invention

[0009] According to the present disclosure, it is possible to provide a turbine wheel and a turbocharger capable of suppressing the generation of abnormal noise. Brief description of the drawings Fig. 1 is a schematic cross-sectional view showing a turbocharger device according to an embodiment. Fig. 2 is a schematic cross-sectional view of a turbine housing according to the embodiment. Fig. 3 is a schematic meridian cross-sectional view of a turbine wheel according to the embodiment. Fig. 4 is a schematic view showing a blade according to the embodiment. Fig. 5 is a schematic graph showing a shape of a leading edge of a first blade according to the embodiment. Fig. Figure 6 is a schematic view of a turbine wheel according to another embodiment. Description of Embodiments

[0010] Some embodiments of the present disclosure will be described below with reference to the accompanying drawings. Dimensions, materials, shapes, relative arrangements, and the like of components described as embodiments or shown in the drawings are not intended to limit the scope of the present disclosure, but are merely illustrative examples.

[0011] For example, an expression representing a relative or absolute arrangement, such as "in a certain direction", "along a certain direction", "parallel", "perpendicular", "center", "concentric" or "coaxial", does not strictly represent only such an arrangement, but also a tolerance or a state relatively displaced by an angle or distance, as long as the same function can be obtained.

[0012] For example, an expression such as "identical," "equal," or "homogeneous," which represents a state in which things are equal to each other, does not strictly represent only the same state, but also represents a tolerance or a state in which there is a difference as far as the same function can be maintained.

[0013] For example, a term representing a shape such as a quadrangular shape or a cylindrical shape not only represents a shape such as a quadrangular shape or a cylindrical shape in a geometrically strict sense, but also represents a shape including a convex portion, a chamfer portion, and the like within a range where the same effect can be obtained.

[0014] However, expressions such as “provided with,” “containing,” or “having” a component are not exclusionary expressions that exclude the existence of other components.

[0015] The same configurations are denoted by the same reference numerals, and the description thereof may be omitted. <Gesamtkonfiguration von Turbolader 1>

[0016] Fig. 1 is a schematic cross-sectional view showing a turbocharger 1 according to an embodiment of the present disclosure. The turbocharger 1 of the present example is mounted in a vehicle, such as an automobile. In the following description, a radial direction and a circumferential direction with respect to a rotating shaft 2 of the turbocharger 1 may be simply referred to as a radial direction and a circumferential direction, respectively. Furthermore, an axial direction of the rotating shaft 2 may be simply referred to as an axial direction.

[0017] The turbocharger 1 includes a rotating shaft 2, a compressor wheel 4 connected to one end portion of the rotating shaft 2, a turbine wheel 3 connected to the other end portion of the rotating shaft 2, a compressor housing 6 housing the compressor wheel 4, and a turbine housing 5 housing the turbine wheel 3. The compressor housing 6 includes an inlet portion 10 in which an inlet path 10A is formed, and a scroll portion 8 in which a scroll flow path 8A is formed.

[0018] Fig. 2 is a schematic cross-sectional view of the turbine housing 5 according to the embodiment of the present disclosure. The turbine housing 5 includes a scroll part 7 in which a scroll flow path 7A is formed inside, and a tongue part 51 formed on an inner peripheral side of the scroll flow path 7A. The tongue part 51 divides the scroll flow path 7A and a flow path 9 formed in a direction in which exhaust gas flows out of the scroll flow path 7A. The tongue part 51 extends obliquely with respect to the axial direction (see Fig. 3). <Turbinenrad 3>

[0019] Fig. 3 is a schematic view of the turbine wheel 3 according to the embodiment of the present disclosure. The turbine wheel 3 shown in the drawing is a radial turbine, but the present disclosure is not limited thereto, and a mixed-flow turbine or the like may be used. An arrow R in the same drawing indicates a rotation direction of the turbine wheel 3.

[0020] The turbine wheel 3 includes a hub 31 having a hub surface 32 inclined with respect to an axis line S of the rotary shaft 2 (see Fig. 1), and a plurality of blades 33 provided on the hub surface 32. The hub 31 is connected to the rotating shaft 2. The plurality of blades 33 are arranged at intervals in the direction of rotation of the hub 31, and each blade 33 includes a leading edge 35, a trailing edge 36, and a tip end 37. As shown in Fig. 3, only long blades may be provided on the hub surface 32 of the turbine wheel 3, or both long blades and short blades may be provided (not shown). However, in the embodiment in which the long blades and short blades are mixed, all of the plurality of blades 33 correspond to the long blades.

[0021] With reference to Fig. 4, a tip-side end 39 and a hub-side end 38, which are both ends of the leading edge 35, are defined. Fig. 4 is a schematic meridian cross-sectional view showing the blade 33 according to the embodiment of the present disclosure. The tip-side end 39 is a part of the leading edge 35 that is connected to the tip end 37. The hub-side end 38 is a part of the leading edge 35 that intersects with an imaginary line L9 extending from the hub surface 32 toward the leading edge 35. Here, the imaginary line L9 is a virtual curve that forms a generatrix (i.e., a Fig. 4 by reference numeral 32) of the hub 31 when viewed along the direction of rotation of the turbine wheel 3. In Fig. Imaginary lines L1 to L8 shown in Figure 4 are virtual curves that evenly divide a space between the tip end 37 and the hub surface 32 in a spanwise direction. Furthermore, in the following description, a part of the trailing edge 36 connected to the tip end 37 may be referred to as a trailing edge tip-side end 41, and an end of the trailing edge 36 located on a side opposite to the trailing edge tip-side end 41 may be referred to as a trailing edge hub-side end 42.

[0022] Back to Fig. 3, when the position in the rotation direction is regarded as a rotation phase, the leading edge 35 of the present embodiment has a twisted shape, so that the rotation phase varies as the position in the axial direction changes. More specifically, the leading edge 35 is formed so that the rotation phase at the hub-side end 38 and the rotation phase at the tip-side end 39 are different from each other. In the following description, a difference in rotation phase between the two may be referred to as a leading edge inclination angle.

[0023] The leading edge inclination angle is correlated with a time required for the blade 33 to pass the tongue portion 51. The required time is a time from when the hub-side end 38 of the leading edge 35 passes the tongue portion 51 until when the tip-side end 39 passes the tongue portion 51.

[0024] A vortex is generated within the turbine housing 5 when the turbocharger 1 is driven. For example, at least one of a vortex generated in the vicinity of the tongue part 51, a vortex generated in the vicinity of the leading edge 35 of the blade 33, and a vortex generated in the vicinity of the trailing edge 36 of the blade 33 is generated within the turbine housing 5 (the vortex generated in the vicinity of the tongue part 51 is Fig. 2 by an arrow A). When the blade 33 periodically collides with the vortex, the vortex gradually grows, and eventually, abnormal noise is generated. The inventor of the present application conceived that if the manner in which the blades 33 and the vortex collide with each other during rotation of the turbine wheel 3 is made irregular, the growth of the vortex can be suppressed, and consequently, the generation of abnormal noise can be suppressed. A configuration embodying the idea will be described below in the order of a first embodiment and a second embodiment. <Spezifische Konfiguration von Turbinenrad 3 (erste Ausführungsform)>

[0025] The specific configuration of the turbine wheel 3 according to the first embodiment will be described with reference to Fig. 3 and Fig. 5. The plurality of blades 33 include at least one first blade 11 and at least one second blade 12, and the first blade 11 and the second blade 12 have shapes that are different from each other. In order to make the shapes of the first blade 11 and the second blade 12 different from each other, various configurations can be used. For example, the shape of the leading edge 35 may be different between the first blade 11 and the second blade 12, the shape of the trailing edge 36 may be different between the first blade 11 and the second blade 12, or a combination of these configurations may be used. In a case where the shape of the leading edge 35 is different, the shape of the part on the tip end 37 side of the leading edge 35 may be different, or the shape of the part on the hub end 38 of the leading edge 35 may be different.Alternatively, the leading edge inclination angle described later may be different. In a case where the shape of the trailing edge 36 is different, the shape of the tip-side end 41 of the trailing edge 36 may be different, the shape of the hub-side end 42 of the trailing edge 36 may be different, or a combination thereof may be used.

[0026] According to the above-described configuration, since the first blade 11 and the second blade 12 having different shapes from each other are included in the plurality of blades 33, even if a vortex is generated inside the turbine housing 5, the manner in which the plurality of blades 33 and the vortex collide with each other during rotation of the turbine wheel 3 can be made irregular, and the growth of the vortex can be suppressed. In this way, the turbine wheel 3 can suppress the generation of abnormal noise. Moreover, when the shapes of the leading edges 35 differ between the first blade 11 and the second blade 12, the time required for the leading edge 35 to pass through the vortex generated in the vicinity of the tongue part 51 of the turbine housing 5 becomes irregular.Accordingly, the leading edge 35 is prevented from periodically interfering with the vortex, and the generation of abnormal noise can be suppressed. Furthermore, when the shape of the trailing edge 36 differs between the first blade 11 and the second blade 12, the time required for the trailing edge 36 to pass through the above-described vortex generated in the vicinity of the trailing edge 36 of the blade 33 becomes irregular. Accordingly, the trailing edge 36 of the blade 33 is prevented from periodically interfering with the vortex, and the generation of abnormal noise can be suppressed.

[0027] A specific configuration in which the shape of the leading edge 35 is made different between the first blade 11 and the second blade 12 will be described with reference to Fig. 5 described. Fig. Fig. 5 is a schematic graph showing the shape of the leading edge 35 of each of the first blade 11 and the second blade 12. In a graph portion where a dashed line and a solid line overlap, the solid line is preferentially shown. A horizontal axis of the graph is an axial direction distance extending from the tip end 41 of the trailing edge and corresponds to a dimension Za in Fig. 4. A vertical axis indicates a rotation phase (θ), which is a position in the circumferential direction, and a positive direction of θ is a rotation direction (arrow R in Fig. 3) of the turbine wheel 3. A thick solid line shown on the graph gives a relationship between the rotation phase of the first blade 11 passing through the tip end 37 of Fig. 4 and the axial direction distance, and a normal solid line indicates a relationship between the rotation phase of the first blade 11 defined by L9 and the axial direction distance. Meanwhile, a thick solid line indicates a relationship between the rotation phase of the second blade 12 defined by the tip end 37 and the axial direction distance, and a normal solid line indicates a relationship between the rotation phase of the second blade 12 defined by L9 and the axial direction distance. As can be seen from the graph, in a range where Za < Z1, the tip end 37 and the imaginary line L9 have substantially the same rotation phase. In other words, both the first blade 11 and the second blade 12 are hardly twisted in a range where Za < Z1.On the other hand, in a range where Za ≥ Z1, the tip end 37 and the imaginary line L9 have different rotation phases, indicating that the leading edge 35 has a twisted shape.

[0028] In Fig. The dimensions α1 and α2 shown in Figure 5 indicate the leading edge inclination angles of the first blade 11 and the second blade 12. As shown in both figures, the leading edge inclination angles are different between the first blade 11 and the second blade 12. The leading edge 35 of the blade 33 is likely to collide with a vortex generated in the vicinity of the tongue portion 51 of the turbine casing 5. In this regard, according to the above-described configuration, since the first blade 11 and the second blade 12 have leading edge inclination angles different from each other, the time required for the vortex to pass the leading edge 35 of each blade 33 can be made irregular. Accordingly, the leading edge 35 of the blade 33 is prevented from periodically interfering with the vortex, and the generation of abnormal noise can be suppressed.

[0029] In some embodiments, the shapes of any two adjacent blades 33 among the plurality of blades 33 may be different from each other. For example, a configuration may be adopted in which the plurality of blades 33 is configured only by the plurality of first blades 11 and the plurality of second blades 12, and the first blades 11 and the second blades 12 are alternately arranged in the circumferential direction. According to the above-described configuration, since the way in which the blades 33 collide with the vortex changes between the two adjacent first blades 11 and second blades 12, the generation of abnormal noise can be suppressed.

[0030] In some embodiments, each of the plurality of blades 33 may have a shape that differs from each other. For example, the leading edge inclination angle may be different among all the blades 33. According to the above-described configuration, since the path along which the blades 33 and the vortex collide with each other during rotation of the turbine wheel 3 is further changed, the generation of abnormal noise can be suppressed.

[0031] Although an example in which the shape of the leading edge 35 differs between the first blade 11 and the second blade 12 has been described as a specific example of the first embodiment, the present disclosure is not limited thereto. For example, a configuration in which the shape of the trailing edge 36 differs between the first blade 11 and the second blade 12 may be adopted. In the turbine casing 5, a vortex may be generated in the vicinity of the trailing edge 36 of the blade 33. When each of the trailing edges 36 periodically collides with the vortex, the vortex grows, and abnormal noise is generated. In this regard, the shape of the trailing edge 36 is made different between the first blade 11 and the second blade 12, and accordingly, the manner in which the blades 33 collide with the vortex can be made irregular, and abnormal noise can be suppressed. <Spezifische Konfiguration von Turbinenrad 3 (zweite Ausführungsform)>

[0032] Fig. 6 is another schematic view showing a specific configuration of the turbine wheel 3. In the same drawing, the plurality of blades 33 constituting the turbine wheel 3 are schematically shown. The plurality of blades 33 include the plurality of first blades 11, and a blade space Bs is formed between two first blades 11 continuously arranged in the circumferential direction. In the example of the drawing, the number of first blades 11 is three, and the number of blade spaces Bs is three. At least one third blade 13 is arranged in each blade space Bs in the plurality of blades 33. The third blade 13 may have a shape different from that of the first blade 11, and may have the same shape as the second blade 12 described above, or may have a shape different from that of the second blade 12.

[0033] In the present embodiment, the number of third blades 13 arranged in the blade spaces Bs is different among the three blade spaces Bs. If Fig. 6 is described as a schematic view, the number of third blades 13 arranged in the first blade space Bs is two, the number of third blades 13 arranged in the second blade space Bs is three, and the number of third blades 13 arranged in the third blade space Bs is four. According to the configuration described above, the cycle in which the plurality of blades 33 collide with the vortex during one rotation of the turbine wheel 3 can be made irregular, and the growth of the vortex can be suppressed. In this way, the generation of abnormal noise can be suppressed.

[0034] The Fig. The plurality of blades 33 shown in Fig. 6 are arranged so that there are two or more types of blade pitches. In the drawing, two third blades 13 are arranged on both sides of each first blade 11, and a blade pitch (θ1) between the third blade 13 and the first blade 11 on one side and a blade pitch (θ2) between the third blade 13 and the first blade 11 on the other side are different from each other. This relationship is established for each of the first blades 11. The blade pitch is, for example, a distance of the tip end 39 (see Fig. 3).

[0035] According to the configuration described above, since the cycle in which the plurality of blades 33 collide with the vortex during one rotation of the turbine wheel 3 is made irregular, the growth of the vortex can be suppressed. Thus, the generation of abnormal noise can be suppressed. The blade pitches can be different among the plurality of blades 33, and even in this case, the advantages described above can be obtained.

[0036] In some embodiments, a blade pitch of any two adjacent blades 33 among the plurality of blades 33 is greater than an angle obtained by dividing 360° by the number of the plurality of blades 33 by 2° or more. In the example of Fig.6, both θ1 and θ2 are equal to or larger than the above angles by 2°. According to the above-described configuration, since the cycle in which the plurality of blades 33 collide with the vortex during one rotation of the turbine wheel 3 is made irregular, the growth of the vortex can be suppressed. Thus, the generation of abnormal noise can be suppressed.

[0037] In some cases, the distance between the tip end 39 of any two adjacent blades 33 among the plurality of blades 33 is within 3°. According to the above-described configuration, since the flow of the exhaust gas supplied from the scroll flow path 8A can be sufficiently received, the flow force of the exhaust gas can be efficiently converted into the rotational force of the turbine wheel 3, and the loss and performance deterioration of the turbocharger 1 can be suppressed. <zusammenfassung>

[0038] The contents described in some embodiments described above are understood, for example, as follows.

[0039] 1) According to at least one embodiment of the present disclosure, there is provided a turbine wheel (3) provided in a turbine housing (5) of a turbocharger (1), the turbine wheel comprising: a hub (31) connected to a rotating shaft (2) of the turbocharger; and a plurality of blades (33) provided on the hub at intervals in a circumferential direction with respect to the rotating shaft, the plurality of blades comprising at least one first blade (11) and at least one second blade (12) having a shape different from that of the first blade.

[0040] According to the configuration 1) described above, since the first blade and the second blade, which have different shapes from each other, are included in the plurality of blades, even if a vortex is generated within the turbine housing, the manner in which the plurality of blades and the vortex collide with each other during rotation of the turbine wheel can be made irregular, and the growth of the vortex can be suppressed. Thus, the turbine wheel can suppress the generation of abnormal noise.

[0041] 2) In some embodiments, in the turbine wheel according to the above-described 1), each of the plurality of blades includes a leading edge (35), and a shape of the leading edge of the first blade and a shape of the leading edge of the second blade are different from each other.

[0042] A leading edge of a blade is likely to collide with a vortex generated in a tongue portion formed in the turbine casing. In this regard, according to the configuration 2) described above, the time required for the vortex to pass the leading edge of each blade can be made irregular because the shapes of the leading edges of the first blade and the second blade are different from each other. Accordingly, the periodic interference of the leading edge of the blade with the vortex is suppressed, and the generation of abnormal noise can be suppressed.

[0043] 3) In some embodiments, in the turbine wheel according to the above-described 1) or 2), when a position in the circumferential direction is defined as a rotational phase and a difference between the rotational phase at a hub-side end (38) of the leading edge and the rotational phase at a tip-side end (39) of the leading edge is defined as a leading edge inclination angle, the leading edge inclination angle of the first blade and the leading edge inclination angle of the second blade are different from each other.

[0044] A leading edge of a blade is likely to collide with a vortex generated in a tongue portion formed in the turbine casing. In this regard, according to the configuration 3) described above, the time required for the vortex to pass the leading edge of each blade can be made irregular because the first blade and the second blade have different leading edge inclination angles. Accordingly, the periodic interference of the leading edge of the blade with the vortex is suppressed, and the generation of abnormal noise can be suppressed.

[0045] 4) In some embodiments, in the turbine wheel according to any one of 1) to 3) described above, each of the plurality of blades includes a trailing edge (36), and a shape of the trailing edge of the first blade and a shape of the trailing edge of the second blade are different from each other.

[0046] According to the configuration 4) described above, the time required for the vortex to pass the trailing edge can be made irregular with respect to the vortex generated around the trailing edge of the blade. Accordingly, the periodic interference of the trailing edge of the blade with the vortex is suppressed, and the generation of abnormal noise can be suppressed.

[0047] 5) In some embodiments, in the turbine wheel according to any one of 1) to 4) described above, shapes of any two adjacent blades among the plurality of blades are different from each other.

[0048] According to the configuration 5) described above, since the way the blade and the vortex collide with each other changes between the two adjacent blades, the generation of abnormal noise can be suppressed.

[0049] 6) In some embodiments, in the turbine wheel according to 5) described above, each of the plurality of blades has a different shape from each other.

[0050] According to the configuration 6) described above, since the path on which the blades and the vortex collide with each other during rotation of the turbine wheel is further changed, the generation of abnormal noise can be suppressed.

[0051] 7) In some embodiments, in the turbine wheel according to any one of 1) to 6) described above, the plurality of blades includes a plurality of the first blades, in a blade space (Bs) formed between two of the first blades continuously arranged in the circumferential direction among the plurality of first blades, at least one of the other blades (third blade 13) is arranged, and the number of the other blades arranged in each of the blade spaces, the number of which is identical to the number of the plurality of first blades, is different among the plurality of blade spaces.

[0052] According to the configuration 7) described above, the cycle in which the multiple blades collide with the vortex during one rotation of the turbine wheel can be made irregular, and the growth of the vortex can be suppressed. Thus, the generation of abnormal noise can be suppressed.

[0053] 8) In some embodiments, in the turbine wheel according to any one of 1) to 7) described above, the plurality of blades are arranged so that there are two or more types of blade pitches.

[0054] According to the configuration described above (8), since the cycle in which the multiple blades collide with the vortex during one rotation of the turbine wheel can be made irregular, the growth of the vortex can be suppressed. Thus, the generation of abnormal noise can be suppressed.

[0055] 9) In some embodiments, in the turbine wheel according to the above-described 8), a blade pitch of any two adjacent blades among the plurality of blades is larger than an angle obtained by dividing 360° by the number of the plurality of blades by 2° or more.

[0056] According to the configuration 9) described above, since the cycle in which the multiple blades collide with the vortex during one rotation of the turbine wheel can be made more irregular, the growth of the vortex can be suppressed. Thus, the generation of abnormal noise can be suppressed.

[0057] 10) In some embodiments, in the turbine wheel according to any one of 1) to 9) described above, a distance between tip-side ends of any two adjacent blades among the plurality of blades is within 3°.

[0058] According to the configuration 10) described above, since the flow of the exhaust gas supplied from the scroll flow path can be sufficiently received, the flow force of the exhaust gas can be efficiently converted into the rotating force of the turbine wheel, and the loss and performance deterioration of the turbocharger can be suppressed.

[0059] 11) According to at least one embodiment of the present disclosure, there is provided a turbocharger (1) comprising: the turbine wheel (3) according to any one of 1) to 10 described above); and a turbine housing (5) accommodating the turbine wheel, wherein the turbine housing includes a scroll part (7) in which a scroll flow path (7A) for allowing an exhaust gas to flow in the circumferential direction is formed on an outer side in a radial direction with respect to the turbine wheel, and a tongue part (51) formed on an inner peripheral side of the scroll flow path.

[0060] According to the configuration 11) described above, even in a case where a vortex is generated in the vicinity of the tongue part, the generation of abnormal noise can be suppressed for the same reason as the configuration 1) described above. List of reference symbols 1 turbocharger 2 rotating shaft 3 Turbine wheel 4 Compressor wheel 5 Turbine housing 6 Compressor housing 7, 8 screw part 7A, 8A Screw flow path 9 Flow path 10 Inlet connection 10A Inlet route 11 first shovel 12 second shovel 13 third shovel 31 Hub 32 hub surface 33 shovel 35 leading edge 36 trailing edge 37 top end 38 hub end 39 tip end 41 tip end of trailing edge 51 Tongue part A Arrow Bs shovel space S axis line α1, α2 dimension QUOTES CONTAINED IN THE DESCRIPTION

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

[0000] JP 6796214

[0004] < / zusammenfassung>

Claims

[1] Turbine wheel provided in a turbine housing of a turbocharger, the turbine wheel comprising: a hub connected to a rotating shaft of the turbocharger; and several blades which are provided at intervals on the hub in a circumferential direction with respect to the rotating shaft, wherein the multiple shovels comprise at least a first shovel and at least a second shovel having a shape different from the shape of the first shovel. [2] Turbine wheel according to claim 1, wherein each of the multiple blades contains a leading edge, and The shape of the leading edge of the first shovel and the shape of the leading edge of the second shovel differ from each other. [3] Turbine wheel according to claim 2, wherein, if a position in the circumferential direction is defined as a rotation phase and a difference between the rotation phase at a hub-side end of the leading edge and the rotation phase at a tip-side end of the leading edge is defined as a leading-edge tilt angle, the leading-edge tilt angle of the first blade and the leading-edge tilt angle of the second blade differ from each other. [4] Turbine wheel according to claim 1, wherein each of the multiple blades contains a trailing edge, and The shape of the trailing edge of the first shovel and the shape of the trailing edge of the second shovel differ from each other. [5] Turbine wheel according to any one of claims 1 to 4, wherein the shapes of any two adjacent blades differ from each other among the multiple blades. [6] Turbine wheel according to claim 5, wherein each of the several blades has a different shape. [7] Turbine wheel according to one of claims 1 to 3, where the multiple shovels include several of the first shovels, in a blade space formed between two of the first blades, which are continuously arranged in the circumferential direction, under the several first blades, at least one of the other blades is arranged, and the number of other blades arranged in each of the blade spaces, the number of which is identical to the number of the multiple first blades, differs among the multiple blade spaces. [8] Turbine wheel according to one of claims 1 to 3, wherein the multiple blades are arranged such that there are two or more types of blade spacing. [9] Turbine wheel according to claim 8, wherein the blade spacing of any two adjacent blades among the multiple blades is greater than an angle obtained by dividing 360° by the number of multiple blades by 2° or more. [10] Turbine wheel according to any one of claims 1 to 3, wherein a distance between the tip ends of any two adjacent blades under the multiple blades is within 3°. [11] Turbochargers, including: the turbine wheel according to one of claims 1 to 3; and a turbine housing that accommodates the turbine wheel, the turbine housing contains: a screw section in which a screw flow path to allow exhaust gas to flow in the circumferential direction is formed on an outside in a radial direction with respect to the turbine wheel, and a tongue-like portion that is formed on an inner circumferential side of the snail's flow path.

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