(19)
(11)EP 2 716 878 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
29.07.2020 Bulletin 2020/31

(21)Application number: 12789256.0

(22)Date of filing:  24.05.2012
(51)International Patent Classification (IPC): 
F01D 17/16(2006.01)
F02B 37/24(2006.01)
(86)International application number:
PCT/JP2012/063385
(87)International publication number:
WO 2012/161280 (29.11.2012 Gazette  2012/48)

(54)

Variable capacity turbocharger with inlet guide vanes

Turbolader mit verstellbarer Leistungsfähigkeit mit Eintrittsleitschaufeln

Turbocompresseur à charge variable avec aubes de guidage d'entrée


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 26.05.2011 JP 2011118104

(43)Date of publication of application:
09.04.2014 Bulletin 2014/15

(73)Proprietor: IHI Corporation
Tokyo 135-8710 (JP)

(72)Inventor:
  • MORITA Isao
    Tokyo 135-8710 (JP)

(74)Representative: Carpmael, Robert Maurice Charles et al
Marks & Clerk LLP 15 Fetter Lane
London EC4A 1BW
London EC4A 1BW (GB)


(56)References cited: : 
EP-A1- 2 476 862
JP-A- 11 257 082
JP-A- 2000 018 004
US-A- 4 172 361
US-B2- 7 255 530
DE-A1-102009 012 132
JP-A- H11 257 082
JP-U- S62 138 834
US-A1- 2004 223 840
US-B2- 7 255 530
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    BACKGROUND ART



    [0001] In a variable-capacity turbocharger, a nozzle is annularly arranged in the periphery of a turbine impeller, and the capacity of the turbine is changed by adjusting the nozzle opening by the rotation angle of the nozzle inlet guide vanes.

    [0002] It is known that when the shape of the nozzle blades that are arranged on the periphery of this kind of turbine impeller is changed, the flow of exhaust gas that is supplied to the turbine impeller changes in conjunction with shape changes of the nozzle blades, and the turbine efficiency changes.

    [0003] For example, Patent Document 1 discloses a nozzle blade in which the leading edge shape and the trailing edge shape are curved in the blade height direction (rotation axis direction).

    [0004] In greater detail, in Patent Document 1, the leading edge shape and the trailing edge shape of the nozzle blade are set so as to curve so that the center in the blade height direction is concave toward the rotation axis side. Accordingly, the turbine efficiency increases.

    PRIOR ART DOCUMENTS


    PATENT DOCUMENTS



    [0005] [Patent Document 1] U.S. Patent No. 7,255,530

    DISCLOSURE OF INVENTION


    PROBLEMS TO BE SOLVED BY THE INVENTION



    [0006] A nozzle blade is sought in which turbine efficiency is obtained that is higher than the nozzle blade disclosed in Patent Document 1.

    [0007] Moreover, in the case of power no longer being transmitted to the nozzle blades for whatever reason, in order to prevent the blocking up of exhaust gas in the turbine, it is preferable for the nozzle to rotate so that the opening of the nozzle increases. However, in the nozzle blade that is disclosed in Patent Document 1, the aforementioned problem is not considered. For this reason, a nozzle blade is sought that improves the turbine efficiency and moreover in which the direction of the torque received from the exhaust gas always becomes the direction in which the nozzle opening increases.

    [0008] The present invention was achieved in view of the problems given above, and has as its object to provide a nozzle blade that is capable of improving the turbine efficiency more than the nozzle blade disclosed in Patent Document 1, and provide a nozzle blade that improves the turbine efficiency and moreover always receives the torque in the direction in which the nozzle opening increases.

    [0009] JPS 62 138834U discloses nozzle inlet guide vanes disposed in a rotatable manner at the periphery of a turbine impeller that a variable-capacity turbocharger is provided with, wherein the leading edge shape in the vane height direction has a curved-line shape that is formed by the distance from the rotation axis of the vane to the leading edge changing depending on the vane height position, and the trailing edge shape in the vane height direction has a straight-line shape that is formed by the distance from the rotation axis of the vane to the trailing edge being constant irrespective of the vane height position.

    [0010] JP2000 018004A, JPH11 257082A and US 4172361 also disclose a nozzle guide vane with a curved leading edge shape and a straight-line trailing edge shape.

    [0011] According to the present invention there is provided a variable capacity turbocharger as defined in Claim 1 as appended hereto.

    EFFECTS OF THE INVENTION



    [0012] The present invention is directed to a variable capacity turbocharger as defined in claim 1.

    [0013] In the variable capacity turbocharger of the present invention, the nozzle is provided with nozzle blades (the inlet guide vanes), a leading edge shape in the nozzle blade height direction has a curved-line shape that is formed by the distance from the rotation axis of the nozzle blade to the leading edge changing depending on the nozzle blade height position, and the trailing edge shape in the nozzle blade height direction has a straight-line shape that is formed by the distance from the rotation axis of the nozzle blade to the trailing edge being constant irrespective of the nozzle blade height position.

    [0014] In this case, it is possible to improve the turbine efficiency more than a nozzle blade in which both the leading edge shape in the nozzle blade height direction and the trailing edge shape in the nozzle blade height direction have curved-line shapes.

    [0015] Also, in the nozzle blade of the present invention, a region in which the distance from the rotation axis to the leading edge is shortest exists in a region that is sandwiched by both ends in the nozzle blade height direction, and the region in which the distance from the rotation axis to the leading edge is shortest is arranged more to the opposing wall side than the center in the nozzle blade height direction.

    [0016] In this case, it is possible to improve the turbine efficiency, and moreover it is always possible to receive the torque in the direction in which the nozzle opening increases.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0017] 

    FIG. 1 is an enlarged cross-sectional view of the essential portions of a turbocharger in which the nozzle blade in one embodiment of the present invention is installed.

    FIG. 2A is schematic view that shows the appearance of rotation of the nozzle blades in one embodiment of the present invention, and shows the state of the opening of the nozzle N being small.

    FIG. 2B is schematic view that shows the appearance of rotation of the nozzle blades in one embodiment of the present invention, and shows the state of the opening of the nozzle N being large.

    FIG. 3A is a schematic view of the nozzle blade in one embodiment of the present invention.

    FIG. 3B is a schematic view of the nozzle blade in one embodiment of the present invention.

    FIG. 4 is a graph that shows the shape of a nozzle blade used in the simulation for describing the effect of the nozzle blade in one embodiment of the present invention.

    FIG. 5 is a graph that shows the shape of a nozzle blade used in the simulation for describing the effect of the nozzle blade in one embodiment of the present invention.

    FIG. 6 is a graph that shows the shape of a nozzle blade used in the simulation for describing the effect of the nozzle blade in one embodiment of the present invention.

    FIG. 7 is a graph that shows the shape of a nozzle blade used in the simulation for describing the effect of the nozzle blade in one embodiment of the present invention.

    FIG. 8 is a graph that shows the result of a simulation for describing the effect of the nozzle blade in one embodiment of the present invention.

    FIG. 9 is a graph that shows the result of a simulation for describing the effect of the nozzle blade in one embodiment of the present invention.

    FIG. 10 is a graph that shows the result of a simulation for describing the effect of the nozzle blade in one embodiment of the present invention.

    FIG. 11 is a graph showing the detailed shape of a nozzle blade that exhibits the highest performance in the simulation for describing the effect of the nozzle blade in one embodiment of the present invention.



    [0018] Hereinbelow, one embodiment of the nozzle blade according to the present invention shall be described, referring to the drawings. Note that in the following drawings, the scale of each member is suitably altered in order to make each member a recognizable size.

    [0019] FIG. 1 is an enlarged cross-sectional view of the essential portions of a turbocharger including a nozzle blade 10 of the present embodiment.

    [0020] As shown in FIG. 1, the turbocharger is provided with a turbine impeller 1 that is rotatively driven by receiving exhaust gas. At the upstream side of the turbine impeller 1 is formed a nozzle N that is formed by a shroud 2 that surrounds the tip side of the turbine blades that the turbine impeller 1 has and a hub 3 (opposing wall) that is separated from the shroud 2 in the direction of the height of the nozzle blade 10 (nozzle blade height) to be oppositely disposed.

    [0021] The nozzle N is provided so as to surround the entire circumference of the turbine impeller 1. By the supply of exhaust gas from the nozzle N to the turbine impeller 1, the exhaust gas is supplied over the entire circumference of the turbine impeller 1.

    [0022] The nozzle blade 10 of the present embodiment is disposed in a rotatable manner in the nozzle N as shown in FIG. 1, and a plurality are arranged annularly along the circumference of the turbine impeller 1 as shown in the schematic drawings of FIG. 2A and FIG. 2B.

    [0023] Note that as shown in FIG. 3A, a shaft portion 20 that takes the rotation axis O of the nozzle blade 10 as its central axis is connected to the nozzle blade 10 in the nozzle blade height direction.

    [0024] As a result of all the shaft portions 20 being rotated in synchronization by a drive portion not illustrated, as shown in FIG. 2A and FIG. 2B, the nozzle blades 10 are rotated and the size of the gap between the nozzle blades 10 changes. Thereby, the opening of the nozzle N is adjusted.

    [0025] Note that FIG. 2A shows the state of the opening of the nozzle N being small, while FIG. 2B shows the state of the opening of the nozzle N being large.

    [0026] In the nozzle blade 10 of the present embodiment, as shown in FIG. 3A, the leading edge shape in the nozzle blade height direction has a curved-line shape that is formed by the distance from the rotation axis O of the nozzle blade to the leading edge changing depending on the nozzle blade height position.

    [0027] Also, in the nozzle blade 10 of the present embodiment, the trailing edge shape in the nozzle blade height direction has a straight-line shape that is formed by the distance from the rotation axis O of the nozzle blade to the trailing edge being constant regardless of the nozzle blade height position.

    [0028] Moreover, in the nozzle blade 10 of the present embodiment, as shown in FIG. 3A, a region (hereinbelow referred to as the shortest camber length region R) at which the length from the rotation axis O to the leading edge is shortest exists in a region sandwiched by both ends in the nozzle edge height direction (the hub-side end and the shroud-side end).

    [0029] Moreover, the shortest camber length region R is disposed more to the hub side than the center in the nozzle blade height direction.

    [0030] Hereinbelow, the effect of the nozzle blade 10 of the present embodiment shall be described, referring to the results of simulation and the like.

    [0031] Note that in the following description, as shown in FIG. 3B, the distance from the rotation axis O to the leading edge is denoted as the leading edge camber length L1, and the distance from the rotation axis O to the trailing edge is denoted as the trailing edge portion camber length L2. Also, the thickness of the blade that is perpendicular with the camber line and the rotation axis O is denoted as the blade thickness, a hypothetical circle that touches the leading edge from the rotation axis O side is denoted as the leading edge side inscribed circle, and a hypothetical circle that touches the trailing edge from the rotation axis O side is denoted as the trailing edge side inscribed circle.

    [0032] Regarding this simulation, the leading edge shape (that is to say, the change profile of the leading edge portion camber length L1 in the blade height direction) and the trailing edge shape (that is to say, the change profile of the trailing edge portion camber length L2 in the blade height direction) use the nozzle blades with the shapes shown in FIG. 4 to FIG. 7 [namely, base, and d3-01 to d3-15 (however, excluding d3-06).]

    [0033] Note that as the length values used in the present simulation, normalized values with the blade thickness as a reference value are used. The longest camber length in the blade height direction of each nozzle blade (Max (L1 + L2)), the shortest camber length in the blade height direction of each nozzle blade (Min (L1 + L2)), and the average value of the camber length in the blade height direction of each nozzle blade (Average (L1+L2)) are set as shown in Table 1.
    [Table 1]
     Max (L1 + L2Min (L1 + L2)Average (L1 + L2)
    base 2.500 2.500 2.500
    d3-01 2.777 2.777 2.777
    d3-02 2.864 2.508 2.716
    d3-03 2.828 2.422 2.591
    d3-04 2.789 2.519 2.755
    d3-05 2.889 2.492 2.694
    d3-07 2.882 2.416 2.651
    d3-08 3.063 2.572 2.817
    d3-09 3.131 2.372 2.724
    d3-10 2.816 2.317 2.565
    d3-11 2.882 2.416 2.651
    d3-12 2.858 2.128 2.508
    d3-13 2.875 2.323 2.604
    d3-14 2.871 2.276 2.580
    d3-15 2.878 2.361 2.623


    [0034] In the present simulation, with the nozzle blade [base], in which the leading edge shape and the trailing edge shape are made to have a straight-line shape, serving as a reference, the torque ratio acting on each nozzle blade [d3-01 to d3-15 (but excluding d3-06)] and the turbine efficiency difference were investigated. The results are shown in Table 2 and FIG. 8. Note that with the torque ratio values of the present simulation, the cases of the torque acting in the direction in which a nozzle opening increases with respect to the nozzle blade are shown as positive, while the cases of the torque acting in the direction in which the nozzle opening decreases with respect to the nozzle blade are shown as negative.
    [Table 2]
    Case NameTorque RatioEfficiency Difference
    d3-01 -367.4% 1.575
    d3-02 -131.1% 1.420
    d3-03 -272.4% 0.779
    d3-04 -272.4% 1.304
    d3-05 -80.0% 1.341
    d3-07 27.8% 1.272
    d3-08 -390.9% 1.960
    d3-09 -152.5% 1.653
    d3-10 -360.7% -3.345
    d3-11 -34.6% 1.425
    d3-12 59.3% 1.270
    d3-13 1.4% 1.458
    d3-14 17.3% 1.427
    d3-15 -12.2% 1.405


    [0035] Based on the aforementioned simulation results, comparing the nozzle blade [d3-10] and the nozzle blades [d3-01 to d3-05, d3-07 to d3-09, and d3-11 to d3-15], it was found that the value of the turbine efficiency difference is extremely high for the nozzle blades [d3-01 to d3-05, d3-07 to d3-09, and d3-11 to d3-15]. That is to say, it was found that for the blades [d3-01 to d3-05, d3-07 to d3-09, and d3-11 to d3-15], the turbine efficiency is high with respect to the nozzle blade [d3-10].

    [0036] As shown in (b) of FIG. 6, in the nozzle blade [d3-10], both the leading edge shape and the trailing edge shape have a curved-line shape in which the central portion juts inward to the rotation axis O side. On the other hand, for the nozzle blades [d3-01 to d3-05, d3-07 to d3-09, and d3-11 to d3-15], as shown in (b) of FIG. 4 to (a) of FIG. 6 and (c) of FIG. 6 to (d) of FIG. 7, the leading edge shape is a curved-line shape, while the trailing edge shape has a straight-line shape.

    [0037] That is to say, those nozzle blades in which only the leading edge shape is a curved-line shape and the trailing edge shape is a straight-line shape were found to have a higher turbine efficiency than those in which both the leading edge shape and the trailing edge shape are curved-line shapes.

    [0038] As described above, in the nozzle blade 10 of the present embodiment, the trailing edge shape in the nozzle blade height direction has a straight-line shape that is formed by the distance from the rotation axis O of the nozzle blade to the trailing edge being constant regardless of the nozzle blade height position.

    [0039] For this reason, the nozzle blade 10 of the present embodiment can improve the turbine efficiency more than the nozzle blade disclosed in Patent Document 1 in which the leading edge shape in the nozzle blade height direction and the trailing edge shape in the nozzle height direction both have curved-line shapes.

    [0040] Also, as shown in Table 3 and FIG. 9, when comparing the nozzle blades [d3-01 to d3-04], the nozzle blade [d3-02] was found to have the highest performance from the advantage of the balance of the turbine efficiency difference and torque ratio being good.
    [Table 3]
     based3-01d3-02d3-03d3-04
    Fully opened capacity difference 0.00% 0.61% 0.32% 0.52% 0.51%
    Torque ratio 0% -367% -131% -272% -272%
    Turbine efficiency difference 0.0 1.6 1.4 0.8 1.3


    [0041] In the nozzle blade [d3-02], the shortest camber length region R exists in a region that is sandwiched by both ends in the nozzle blade height direction (namely, the hub-side end and the shroud-side end). That is to say, the nozzle blade [d3-02] has a shape in which both ends in the nozzle blade height direction have a longer camber length than the central portion.

    [0042] In this way, from the aforementioned simulation, it was found that due to the shortest camber length region R existing in the region that is sandwiched by both ends in the nozzle blade height direction (namely, the hub-side end and the shroud-side end), it is possible to improve the turbine efficiency. Moreover, it was found that the nozzle blade can always receive the torque in the direction in which the nozzle opening increases.

    [0043] In the nozzle blade 10 of the present embodiment, the shortest camber length region R exists in a region that is sandwiched by both ends (the hub-side end and the shroud-side end) in the nozzle blade height direction.

    [0044] For this reason, it is always possible for the nozzle blade 10 of the present embodiment to receive the torque in the direction in which the nozzle opening increases.

    [0045] Also, as shown in Table 4 and FIG. 10, comparing the nozzle blades [d3-02, d3-05, and d3-07], the performance was found to increase in the order of nozzle blade [d3-02], nozzle blade [d3-05], and nozzle blade [d3-07] from the standpoint of the balance of turbine efficiency difference and torque ratio.
    [Table 4]
     based3-01d3-02d3-03d3-04
    Fully opened capacity difference 0.00% 0.61% 0.32% 0.52% 0.51%
    Torque ratio 0% -367% -131% -272% -272%
    Turbine efficiency difference 0.0 1.6 1.4 0.8 1.3


    [0046] In the nozzle blades [d3-02, d3-05, and d3-07], the shortest camber length region R exists in a region that is sandwiched by both ends (the hub-side end and the shroud-side end) in the nozzle blade height direction. However, the shortest camber length region R approaches the hub 3 side in the order of the nozzle blade [d3-02], the nozzle blade [d3-05], and the nozzle blade [d3-07].

    [0047] Accordingly, from the aforementioned simulation, on the premise of the shortest camber length region R existing in a region that is sandwiched by both ends (the hub-side end and the shroud-side end) in the nozzle blade height direction, it was found that is possible to improve the turbine efficiency by the shortest camber length region R approaching the hub 3 side. Moreover, it was found that the nozzle blade can always receive the torque in the direction in which the nozzle opening increases.

    [0048] The nozzle blade 10 of the present embodiment has a shape in which the shortest camber length region R exists in a region that is sandwiched by both ends (the hub-side end and the shroud-side end) in the nozzle blade height direction, and moreover in which the shortest camber length region R approaches the hub 3 side.

    [0049] For this reason, according to the nozzle blade 10 of the present embodiment, it is possible to improve the turbine efficiency, and moreover it is always possible to receive the torque in the direction in which the nozzle opening increases.

    [0050] Referring to Table 2 and FIG. 8, comparing all of the nozzle blades [base, d3-01 to d3-15 (but excluding d3-06)], the performance of the nozzle blade [d3-12] was found to be high from the advantage of the balance of the turbine efficiency difference and torque ratio being good.

    [0051] FIG. 11 is a drawing that shows the shape of the nozzle blade [d3-12], and shows a graph that shows the relation of camber length and blade thickness by normalized values with the blade thickness serving as the reference value, and the leading edge inscribed circle diameter and the trailing edge inscribed circle diameter.

    [0052] Note that in the nozzle blade [d3-12], similarly to the nozzle blade 10 of the present embodiment, the trailing edge shape in the nozzle blade height direction has a straight-line shape that is formed by the distance from the rotation axis O of the nozzle blade to the trailing edge being constant regardless of the nozzle blade height position.

    [0053] Also, in the nozzle blade [d3-12], similarly to the nozzle blade 10 of the present embodiment, the shortest camber length region R exists in a region that is sandwiched by both ends (the hub-side end and the shroud-side end) in the nozzle blade height direction. The shortest camber length region R is disposed more to the hub side than the center in the nozzle blade height direction.

    [0054] Moreover, in the nozzle blade [d3-12], as shown in Table 1 and FIG. 11, the normalized values having the nozzle blade height as a reference value are set so that the length from the leading edge to the trailing edge is 2.128 in the region in the nozzle blade height direction where the length from the leading edge to the trailing edge is shortest, the length from the leading edge to the trailing edge is 2.858 in the region in the nozzle blade height direction where the length from the leading edge to the trailing edge is longest, and the average value of the length from the leading edge to the trailing edge is 2.508 in the nozzle blade height direction. Also, the normalized values having the nozzle blade height as a reference value are set so that the leading edge inscribed circle diameter at the region in the nozzle blade height direction in which the length from the leading edge to the trailing edge is shortest is 0.146, the leading edge inscribed circle diameter at the region in the nozzle blade height direction in which the length from the leading edge to the trailing edge is longest is 0.142, the trailing edge inscribed circle diameter at the region in the nozzle blade height direction in which the length from the leading edge to the trailing edge is shortest is 0.04, and the trailing edge inscribed circle diameter at the region in the nozzle blade height direction in which the length from the leading edge to the trailing edge is longest is 0.04.

    [0055] That is to say, by setting the shape of the nozzle blade 10 of the present embodiment based on the normalized values described above, it is capable of further improving the turbine efficiency, and moreover it is always capable of receiving a large torque in the direction in which the nozzle opening becomes large.

    [0056] Note that without being limited to the shape of the nozzle blade [d3-12], the normalized values having the nozzle blade height as a reference value are set so that the length from the leading edge to the trailing edge in the region in the nozzle blade height direction where the length from the leading edge to the trailing edge is shortest is in the range of 2.0 to 2.2, the length from the leading edge to the trailing edge in the region in the nozzle blade height direction where the length from the leading edge to the trailing edge is longest is in the range of 2.7 to 2.9, and the average value of the length from the leading edge to the trailing edge in the nozzle blade height direction is in the range of 2.4 to 2.6. Also, the normalized values having the nozzle blade height as a reference value are set so that the leading edge inscribed circle diameter at the region in the nozzle blade height direction in which the length from the leading edge to the trailing edge is shortest is in the range of 0.1 to 0.2, the leading edge inscribed circle diameter at the region in the nozzle blade height direction in which the length from the leading edge to the trailing edge is longest is in the range of 0.1 to 0.2, the trailing edge inscribed circle diameter at the region in the nozzle blade height direction in which the length from the leading edge to the trailing edge is shortest is in the range of 0.01 to 0.1, and the trailing edge inscribed circle diameter at the region in the nozzle blade height direction in which the length from the leading edge to the trailing edge is longest is in the range of 0.01 to 0.1. Thereby, it is possible to further improve the turbine efficiency, and moreover it is always possible to receive large torque in the direction in which the nozzle opening becomes large.

    [0057] Hereinabove, the preferred embodiment of the present invention was described while referring to the appended drawings, but the present invention is not limited to the aforementioned embodiment.

    [0058] The various shapes and combinations of each composite member shown in the embodiment described above refer to only a single example, and may be altered in various ways based on design requirements and so forth within a scope that does not deviate from the subject matter of the present invention as claimed.

    [0059] For example, the number of the nozzle blades 10 that are arranged around the turbine impeller 1 shown in FIG. 2A and FIG. 2B is one example, and may be fewer or may be more than the number shown in FIG. 2A and FIG. 2B.

    [0060] Also, it is not necessary for all of the nozzle blades that are disposed around the turbine impeller 1 to be the nozzle blade 10 of the embodiment described above.

    INDUSTRIAL APPLICABILITY



    [0061] According to the nozzle blade of the present invention, it is possible to provide a nozzle blade that can improve the turbine efficiency, and that can always receive the torque in the direction in which the nozzle opening becomes large.

    DESCRIPTION OF THE REFERENCE SYMBOLS



    [0062] 10 nozzle blade, 1 turbine impeller, 2 shroud, 3 hub (opposing wall), N nozzle


    Claims

    1. A variable capacity turbocharger comprising:

    a turbine impeller (1) which includes turbine blades;

    a plurality of inlet guide vanes (10), each having a shaft portion (20), being rotatable around an axis (O) of the shaft portion (20), and being disposed at the periphery of the turbine impeller (1);

    a shroud (2) surrounding a tip side of the turbine blades;

    an opposing wall (3) that is separated from the shroud (2) in a height direction of the inlet guide vanes (10); and

    a nozzle (N) sandwiched by the shroud (2) and the opposing wall (3), the nozzle (N) being provided with the inlet guide vanes (10), wherein

    a leading edge of the inlet guide vanes (10) in the height direction of the inlet guide vanes (10) has a curved-line shape relative to the distance from the axis (O) of the shaft portion (20) of the inlet guide vanes (10) to the leading edge which distance changes depending on a height position of the inlet guide vanes (10),

    a trailing edge of the inlet guide vanes (10) in the height direction of the inlet guide vanes (10) has a straight-line shape such that the distance from the axis (O) of the shaft portion (20) of the inlet guide vanes (10) to the trailing edge is constant irrespective of the height position of the inlet guide vanes (10),

    a region (R) at which the distance from the axis (O) of the shaft portion (20) to the leading edge is shortest is located in a region sandwiched by both ends in the height direction of the inlet guide vanes (10),

    characterized in that:

    the region (R) is located between the opposing wall (3) and a mid-height section of the inlet guide vanes (10) in the height direction of the inlet guide vanes (10),

    the region (R) is closer to the opposing wall (3) than the mid-height section of the inlet guide vanes (10) in the height direction of the inlet guide vanes (10),

    the curved-line shape extends along the entire height of the inlet guide vanes (10), and

    the curved-line shape results in a decreasing vane camber length from both ends in the height direction of the inlet guide vanes (10) toward the region (R).


     


    Ansprüche

    1. Turbolader mit veränderlichem Leistungsvermögen, der Folgendes umfasst:

    ein Turbinenlaufrad (1), das Turbinenschaufeln einschließt,

    eine Mehrzahl an Einlassleitschaufeln (10), von denen jede einen Schaftabschnitt (20) aufweist, um eine Achse (O) des Schaftabschnitts (20) drehbar ist und am Umfang des Turbinenlaufrades (1) angeordnet ist,

    ein Deckband (2), das eine Spitzenseite der Turbinenschaufeln umgibt,

    eine gegenüberliegende Wand (3), die in einer Höhenrichtung der Einlassleitschaufeln (10) von dem Deckband (2) getrennt ist, und

    eine Düse (N), die durch das Deckband (2) und die gegenüberliegende Wand (3) eingeklemmt wird, wobei die Düse (N) mit den Einlassleitschaufeln (10) versehen ist, wobei

    eine vordere Kante der Einlassleitschaufeln (10) in der Höhenrichtung der Einlassleitschaufeln (10) eine krummlinige Form im Verhältnis zu der Entfernung von der Achse (O) des Schaftabschnitts (20) der Einlassleitschaufeln (10) zu der vorderen Kante aufweist, wobei sich die Entfernung in Abhängigkeit von einer Höhenposition der Einlassleitschaufeln (10) ändert,

    eine hintere Kante der Einlassleitschaufeln (10) in der Höhenrichtung der Einlassleitschaufeln (10) eine geradlinige Form aufweist, so dass die Entfernung von der Achse (O) des Schaftabschnitts (20) der Einlassleitschaufeln (10) zu der hinteren Kante ungeachtet der Höhenposition der Einlassleitschaufeln (10) konstant ist,

    ein Bereich (R), an dem die Entfernung von der Achse (O) des Schaftabschnitts (20) zu der vorderen Kante am kürzesten ist, in einem Bereich angeordnet ist, der durch beide Enden in der Höhenrichtung der Einlassleitschaufeln (10) eingeklemmt wird,

    dadurch gekennzeichnet, dass:

    der Bereich (R) zwischen der gegenüberliegenden Wand (3) und einer Sektion mittlerer Höhe der Einlassleitschaufeln (10) in der Höhenrichtung der Einlassleitschaufeln (10) angeordnet ist,

    der Bereich (R) der gegenüberliegenden Wand (3) näher ist, als die Sektion mittlerer Höhe der Einlassleitschaufeln (10) in der Höhenrichtung der Einlassleitschaufeln (10),

    sich die krummlinige Form entlang der gesamten Höhe der Einlassleitschaufeln (10) erstreckt und

    die krummlinige Form zu einer abnehmenden Schaufelkammerlänge von beiden Enden in der Höhenrichtung der Einlassleitschaufeln (10) zu dem Bereich (R) hin führt.


     


    Revendications

    1. Turbocompresseur à charge variable comprenant :

    un rotor de turbine (1) qui inclut des pales de turbine ;

    une pluralité d'aubes de guidage d'entrée (10), présentant chacune une partie d'arbre (20), pouvant tourner autour d'un axe (O) de la partie d'arbre (20), et étant disposées à la périphérie du rotor de turbine (1) ;

    un hauban (2) entourant un côté de pointe des pales de turbine ;

    une paroi opposée (3) qui est séparée du hauban (2) dans un sens de la hauteur des aubes de guidage d'entrée (10) ; et

    une buse (N) prise en sandwich par le hauban (2) et la paroi opposée (3), la buse (N) étant dotée des aubes de guidage d'entrée (10), dans lequel

    un bord d'attaque des aubes de guidage d'entrée (10) dans le sens de la hauteur des aubes de guidage d'entrée (10) présente une forme en ligne incurvée relative à la distance entre l'axe (O) de la partie d'arbre (20) des aubes de guidage d'entrée (10) et le bord d'attaque, ladite distance changeant en fonction d'une position en hauteur des aubes de guidage d'entrée (10),

    un bord arrière des aubes de guidage d'entrée (10) dans le sens de la hauteur des aubes de guidage d'entrée (10) présente une forme en ligne droite, de sorte que la distance de l'axe (O) de la partie d'arbre (20) des aubes de guidage d'entrée (10) jusqu'au bord arrière est constante, quelle que soit la position en hauteur des aubes de guidage d'entrée (10),

    une région (R) où la distance de l'axe (O) de la partie d'arbre (20) au bord d'attaque est la plus courte est située dans une région prise en sandwich par les deux extrémités dans le sens de la hauteur des aubes de guidage d'entrée (10),

    caractérisé en ce que :

    la région (R) est située entre la paroi opposée (3) et une section à mi-hauteur des aubes de guidage d'entrée (10) dans le sens de la hauteur des aubes de guidage d'entrée (10),

    la région (R) est plus proche de la paroi opposée (3) que la section à mi-hauteur des aubes de guidage d'entrée (10) dans le sens de la hauteur des aubes de guidage d'entrée (10),

    la forme en ligne incurvée s'étend sur toute la hauteur des aubes de guidage d'entrée (10), et

    la forme en ligne incurvée provoque une longueur de cambrure d'aube décroissante depuis les deux extrémités dans le sens de la hauteur des aubes de guidage d'entrée (10) vers la région (R).


     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



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    Patent documents cited in the description