TURBINE AND TURBOCHARGER

Abstract

A turbine comprises a first casing having a screw-shaped flow path, a first plate-like element containing an annular first plate section, a second plate-like element containing an annular second plate section forming a gas flow path between the first plate section and the second plate section, a second casing having a facing surface that is oriented towards a rear surface of the first plate section on a side opposite the gas flow path, with a first chamber inserted between them, an annular element arranged in the first chamber that rotates with respect to the first plate-like element, a linking element having one end connected to the annular element and the other end connected to a variable nozzle blade, and a positioning pin having one end extending into a first hole formed on the rear surface of the first plate section.is fitted and the other end is fitted into a second hole formed on the facing surface of the second housing, and a stopper section, wherein a first gap is formed between itself and the facing surface or between itself and the first plate section, and the first gap is smaller than a second gap between the annular element and the facing surface and a third gap between the linking element and the facing surface.

Description

Technical area

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

[0002] As a turbocharger (supercharger) that utilizes energy from exhaust gas of an internal combustion engine (engine) to supercharge the intake of the internal combustion engine, a turbocharger including a variable-capacity turbine is known (see, for example, PTL 1). In the variable-capacity turbine, a plurality of guide vanes are arranged in a circumferential direction of a turbine wheel in an exhaust flow path for conveying the exhaust gas from a scroll flow path of the turbine to the turbine wheel. A flow path cross-sectional area (the flow path between adjacent nozzle vanes) of the exhaust flow path can be adjusted by changing a vane angle of the nozzle vanes from the outside using an actuator. The variable-capacity turbine is a turbine that increases a supercharging effect by changing a flow velocity or pressure of the exhaust gas supplied to the turbine wheel.

[0003] In PTL 1, two plate-like members (a nozzle holder and a nozzle plate) constituting an exhaust gas flow path are connected to each other by a nozzle holder, and a press-fit pin (positioning pin) for positioning the nozzle holder and a bearing housing is press-fitted into a press-fit hole formed in the nozzle holder. Citation listPatent literature

[0004] [PTL 1] Japanese Unexamined Patent Application Publication No. 2013-072401 Summary of the inventionTechnical problem

[0005] There are concerns that due to thermal deformation during operation of the variable capacity turbine, the nozzle holder approaches a bearing housing side, the press-fit pin is excessively inserted into the press-fit hole, frictional resistance increases between the press-fit pin and the press-fit hole, and the press-fit pin gets stuck in the press-fit hole. In a case where the press-fit pin gets stuck in the press-fit hole, there are concerns that a variable nozzle mechanism will be lifted and exposed to a risk of abrasion due to vibration and the like, without being able to maintain a support structure for the variable nozzle mechanism.

[0006] In view of the above circumstances, an object of at least one embodiment of the present disclosure is to provide a turbine and a turbocharger that can stably maintain a support structure of a variable nozzle unit by suppressing sticking of a positioning pin. Solution to the problem

[0007] A turbine according to at least one embodiment of the present disclosure comprises: a first housing having a screw flow path; a turbine wheel provided on an inner peripheral side of the screw flow path; a first plate-like member including an annular first plate portion; a second plate-like member including an annular second plate portion disposed to face the first plate portion and forming a gas flow path between the first plate portion and the second plate portion from the scroll flow path toward the turbine wheel; at least one variable nozzle vane arranged in the gas flow path; a second housing having a facing surface opposite to a rear surface of the first plate portion on a side opposite to a flow path wall surface facing the gas flow path, with a first space interposed therebetween; an annular member disposed in the first space and configured to rotate with respect to the first plate-like member by means of an external driving force; at least one linking member, one end of which is connected to the annular member and the other end of which is connected to the variable nozzle vane, which changes a vane angle of the variable nozzle vane connected to the other end in conjunction with the rotation of the annular member; a biasing member disposed between the second housing and the first plate-like member and configured to bias the first plate portion toward one side of the gas flow path; at least one positioning pin, one end of which is fitted into a first hole formed on the rear surface of the first plate portion and the other end of which is fitted into a second hole formed on the facing surface of the second housing; and at least one stopper portion provided on the facing surface or the first plate portion, wherein a first gap is formed between the stopper portion and the facing surface or between the stopper portion and the first plate portion, the first gap being smaller than a second gap between the annular member and the facing surface and a third gap between the at least one linking member and the facing surface.

[0008] A turbocharger according to at least one embodiment of the present disclosure includes the turbine and a centrifugal compressor configured to be driven by the turbine. Advantageous effects of the invention

[0009] According to at least one embodiment of the present disclosure, a turbine and a turbocharger are provided that can stably maintain a support structure of a variable nozzle unit by suppressing sticking of a positioning pin. Brief Description of the Drawings Fig. 1 is a schematic view of an internal combustion engine system including a turbocharger according to one embodiment. Fig. 2 is a schematic cross-sectional view along an axis line of a turbine according to an embodiment. Fig. 3 is a schematic view of a variable nozzle unit provided in the turbine according to an embodiment. Fig. 4 is a schematic cross-sectional view illustrating a cross section along an axis line on one side with respect to the axis line of the turbine according to an embodiment. Fig. 5 is a schematic cross-sectional view illustrating a cross section along the axis line on one side with respect to the axis line of the turbine according to an embodiment. Fig. 6 is a schematic cross-sectional view illustrating a cross section along the axis line on one side with respect to the axis line of the turbine according to an embodiment. Fig. 7 is a schematic cross-sectional view illustrating a cross section along the axis line on one side with respect to the axis line of the turbine according to an embodiment. Fig. 8 is an explanatory diagram for describing a side near the tongue portion and a side away from the tongue portion. Fig. 9 is a schematic view of a variable nozzle unit provided in the turbine according to an embodiment. Fig. 10 is a schematic cross-sectional view illustrating a cross section along the axis line on one side with respect to the axis line of the turbine according to an 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 illustrated in the drawings are not intended to limit the scope of the present disclosure, but are merely illustrative examples. (turbocharger)

[0011] Fig. 1 is a schematic view of an internal combustion engine system 10 including a turbocharger 1 according to one embodiment. A turbine 2 according to the present disclosure may be mounted, for example, in a turbocharger (supercharger) 1 for a car, a ship, or an industrial application (for example, for land-based power generation). In each of the following embodiments, the turbine 2 mounted in the turbocharger 1 is described as an example, but the turbine 2 according to the present disclosure is not limited to the turbine mounted in the turbocharger 1. Furthermore, an operating fluid of the turbine 2 need not be limited to an exhaust gas.That is, the turbine 2 of the present disclosure may be configured to convert operating fluid energy into mechanical power (e.g., rotational power), and may be configured as a standalone turbine 2 or in combination with a mechanism or other device as a centrifugal compressor 12. Furthermore, the use of the turbine 2 and the like need not be limited.

[0012] As in Fig. As shown in Figure 1, according to some embodiments, the turbocharger 1 is configured to be driven by energy from exhaust gas discharged from an internal combustion engine (engine) 11 and to compress a fluid (e.g., air). The turbocharger 1 includes the turbine 2 and the centrifugal compressor 12, which is configured to be driven by the turbine 2.

[0013] The centrifugal compressor 12 includes an impeller 13 and a compressor housing 14 configured to rotatably receive the impeller 13. The turbine 2 includes at least one turbine wheel 3, a first housing (turbine housing) 4, and a second housing (bearing housing) 5 configured to rotatably receive the turbine wheel 3 between the first housing 4 and the second housing 5.

[0014] As in Fig. 1, the turbocharger 1 further includes a rotating shaft 15 to which the turbine wheel 3 is connected at one end and to which the impeller 13 is connected at the other end, and a bearing 16 configured to rotatably support the rotating shaft 15 between the turbine wheel 3 and the impeller 13. The second housing 5 is arranged between the first housing 4 and the compressor housing 14 and is connected to each of the first housing 4 and the compressor housing 14, for example, via a fastening member (not shown) such as a bolt or a nut. The second housing 5 may be configured to accommodate the bearing 16.

[0015] The turbine 2 of the turbocharger 1 is configured to rotate the turbine wheel 3 using energy from the exhaust gas discharged from the internal combustion engine 11. The impeller 13 is connected to the turbine wheel 3 on the same axis via the rotating shaft 15, and thus the impeller 13 is driven to rotate about an axis LA in conjunction with the rotation of the turbine wheel 3. The centrifugal compressor 12 of the turbocharger 1 is configured to drive the impeller 13 to rotate about the axis LA to draw air (air supply, gas) into the compressor housing 14, compress the air, and deliver the compressed air to the internal combustion engine 11.

[0016] The compressed air delivered by the centrifugal compressor 12 to the internal combustion engine 11 is supplied for combustion in the internal combustion engine 11. The exhaust gas generated by the combustion in the internal combustion engine 11 is delivered from the internal combustion engine 11 to the turbine 2 to rotate the turbine wheel 3. (wheel)

[0017] As in Fig. 1, the impeller 13 is connected to the other end side of the rotating shaft 15 and is thus provided integrally with the rotating shaft 15, rotatable around an axis line of the impeller 13 as a center. The impeller 13 is configured to guide the air introduced along an axial direction of the impeller 13 in a radial direction outward of the impeller 13. In the illustrated embodiment, the impeller 13 is an open-type impeller that does not include an annular member surrounding an outer periphery of blades of the impeller 13. (compressor housing)

[0018] A gas introduction flow path 141 and a scroll flow path 142 are formed within the compressor housing 14. In other words, the compressor housing 14 includes a gas introduction flow path 141 and a scroll flow path 142.

[0019] The gas introduction flow path 141 is a flow path for sucking air (gas) from the outside of the compressor housing 14 (centrifugal compressor 12) and guiding the sucked air to the impeller 13. The gas introduction flow path 141 is provided on one side of the impeller 13 in the axial direction with respect to the impeller 13 and extends along the axial direction of the impeller 13. By rotating the impeller 13, air is sucked into the gas introduction flow path 141 from the outside of the compressor housing 14, and the sucked air flows toward the impeller 13 in the gas introduction flow path 141 and is guided to the impeller 13.

[0020] The scroll flow path 142 is provided on an outer peripheral side of the impeller 13 and consists of a spiral flow path extending along a circumferential direction of the impeller 13. The air passing through the impeller 13 and compressed by the impeller 13 is guided to the scroll flow path 142. The compressed air flowing through the scroll flow path 142 is guided to the internal combustion engine 11.

[0021] Fig. 2 is a schematic cross-sectional view taken along the axis line LA of the turbine 2 according to an embodiment. Hereinafter, a direction in which the axis line LA of the turbine wheel 3 extends is defined as an axial direction of the turbine wheel 3, a direction perpendicular to the axis line LA is defined as a radial direction of the turbine wheel 3, and a circumferential direction around the axis line LA is defined as a circumferential direction of the turbine wheel 3. Hereinafter, a side (right side in Fig. 2), on which the first casing 4 is positioned with respect to the second casing 5 in the axial direction of the turbine wheel 3, is defined as a front side, and a side (opposite the front side, left side in Fig. 2) on which the second housing 5 is positioned with respect to the first housing 4 is defined as a back side. (turbine wheel)

[0022] As in Fig. As shown in Fig. 2, the turbine wheel 3 includes a hub 31 having a substantially truncated conical shape and a plurality of turbine blades 32 provided on an outer peripheral surface of the hub 31. Each of the plurality of turbine blades 32 is arranged at intervals in the circumferential direction around the axis line LA. The hub 31 and the plurality of turbine blades 32 are provided to be integrally rotatable with the rotating shaft 15 around the axis line LA as the center. The turbine wheel 3 is configured to guide the exhaust gas introduced from the outside of the turbine wheel 3 in the radial direction to the front side of the turbine wheel 3 along the axial direction of the turbine wheel 3. (Screw flow path and exhaust gas discharge flow path)

[0023] Within the first casing 4, a scroll flow path 41 for guiding the exhaust gas discharged from the internal combustion engine 11 to the turbine wheel 3 and an exhaust gas discharge flow path 42 for discharging the exhaust gas passing through the turbine wheel 3 to the outside of the first casing 4 (turbine 2) are formed. In other words, the first casing 4 includes the scroll flow path 41 and the exhaust gas discharge flow path 42. The scroll flow path 41 is provided on an outer peripheral side of the turbine wheel 3 and consists of a spiral flow path extending along the circumferential direction of the turbine wheel 3. The exhaust gas discharge flow path 42 extends from the turbine wheel 3 toward the front side along the axial direction of the turbine wheel 3.

[0024] The first housing 4 and the second housing 5 are fixed to each other, so that an internal space 43 connecting the scroll flow path 41 and the exhaust gas discharge flow path 42 is formed between the first housing 4 and the second housing 5. The turbine wheel 3 is rotatably accommodated in the internal space 43 with respect to the first housing 4 and the second housing 5. The turbine wheel 3 is provided on an inner peripheral side of the scroll flow path 41.

[0025] The exhaust gas discharged from the internal combustion engine 11 is guided to the turbine wheel 3 through the scroll flow path 41, and the turbine wheel 3 is driven to rotate. The exhaust gas, which causes the turbine wheel 3 to rotate, is discharged to the outside of the first casing 4 (turbine 2) via the exhaust discharge flow path 42. (Variable nozzle unit)

[0026] Fig. 3 is a schematic view of a variable nozzle unit 6 provided in the turbine 2 according to an embodiment. As shown in Fig. As shown in Fig. 2, the turbine 2 further includes the variable nozzle unit 6, which is housed on the outer peripheral side of the turbine wheel 3 in the above-mentioned internal space 43. The variable nozzle unit 6 forms a gas flow path (exhaust gas flow path) 43A for guiding the exhaust gas from the scroll flow path 41 to the turbine wheel 3 and adjusts the flow of the exhaust gas in the gas flow path 43A. The gas flow path 43A is a part of the internal space 43. The gas flow path 43A is formed between the scroll flow path 41 and the turbine wheel 3 so as to surround a periphery of the turbine wheel 3 (the outer side in the radial direction).

[0027] As in Fig. 2, the variable nozzle unit 6 includes a first plate-like element (nozzle holder) 7, a second plate-like element (nozzle plate) 8, at least one (in the example shown, several) variable nozzle vane 61, an annular element (drive ring) 62, and at least one (in the example shown, several) linking element (lever plate) 63. (First plate-like element)

[0028] The first plate-like member (nozzle holder) 7 includes an annular first plate portion 71 extending along the circumferential direction of the turbine wheel 3 on the outer peripheral side of the turbine wheel 3. A first flow path wall surface 72 facing the gas flow path 43A is formed on a front side of the first plate portion 71, and a rear surface 73 is formed on a back side of the first plate portion 71, that is, on a side opposite the first flow path wall surface 72. (Second plate-like element)

[0029] The second plate-like member (nozzle plate) 8 includes an annular second plate portion 81 disposed facing the first plate portion 71, and forming a gas flow path 43A between the first plate portion and the second plate portion 81 from the scroll flow path 41 to the turbine wheel 3. The second plate portion 81 is disposed on the front side of the first plate portion 71 and extends on the outer peripheral side of the turbine wheel 3 along the circumferential direction of the turbine wheel 3. A second flow path wall surface 82 facing the gas flow path 43A is formed on a back side of the second plate portion 81.

[0030] The gas flow path 43A is formed between the first flow path wall surface 72 and the second flow path wall surface 82. The first flow path wall surface 72 is positioned on a back side of the second flow path wall surface 82 and faces the second flow path wall surface 82. The exhaust gas introduced into the turbine 2 is guided through the scroll flow path 41 and then through the gas flow path 43A to the turbine wheel 3, rotating the turbine wheel 3. (support element)

[0031] As in Fig. 2, the variable nozzle unit 6 may further include at least one (for example, a plurality of) support members (nozzle holders) 64 that support the first plate-like member 7 and the second plate-like member 8 in a state where they are separated from each other. Each of the plurality of support members 64 is arranged at intervals in the circumferential direction of the turbine wheel 3. One side of each of the plurality of support members 64 is fixed to the first plate portion 71, and the other side thereof is fixed to the second plate portion 81. The second plate-like member 8 is supported by the support member 64 so as to be separated from the first plate-like member 7 on the front side. (first room)

[0032] The second housing 5 has a facing surface 51 facing the rear surface 73 of the first plate portion 71, with a first space 43B interposed therebetween. The first space 43B is a part of the internal space 43 and is formed on a side opposite the gas flow path 43A, with the first plate portion 71 interposed therebetween. (Variable nozzle vane)

[0033] Each of the plurality of variable nozzle vanes 61 is arranged in the gas flow path 43A and is rotatably supported about a rotation center RC of each of the first plate portions 71 (first plate-like elements 7). The plurality of variable nozzle vanes 61 are arranged at intervals in the circumferential direction of the turbine wheel 3. (Ring-shaped element)

[0034] The annular member (drive ring) 62 is arranged in the first space 43B and is configured to be rotated by an external driving force with respect to the first plate-like member 7 about an axis line LB of the annular member 62 (variable nozzle unit 6). (Drive mechanism unit and control device)

[0035] As in Fig. As shown in Figure 2, the turbine 2 further includes a drive mechanism unit (actuator) 65 configured to transmit a driving force to the annular member 62 and rotate the annular member 62 about the axis line LB, and a control device (controller) 66 configured to control the rotation of the annular member 62 about the axis line LB. The drive mechanism unit 65 includes an electric motor that generates a driving force, an air cylinder that transmits the driving force, and the like. (Linking element)

[0036] As in Fig. As shown in Fig. 3, the variable nozzle unit 6 includes linking members (lever plates) 63 equal in number to the variable nozzle vanes 61. Each of the plurality of linking members 63 is disposed in the first space 43B, has one end 631 connected to the annular member 62, has the other end 632 connected to the variable nozzle vane 61, and is configured to change the one vane angle of the variable nozzle vane 61 connected to the other end 632 in conjunction with the rotation of the annular member 62.

[0037] At the Fig. In the embodiment shown in Fig. 3, one end 631 of each linking member 63 includes a fitting portion 631A fitted into a fitting target portion 621 formed in the annular member 62. The fitting target portion 621 includes a groove portion 621A formed in an outer peripheral edge portion of the annular member 62, and the fitting portion 631A is received in the groove portion 621A and is loosely fitted into the groove portion 621A. The first plate portion 71 has a plurality of through holes 74 penetrating the first flow path wall surface 72 and the back surface 73. Each of the plurality of through holes 74 is arranged at intervals in the circumferential direction of the turbine wheel 3. The first plate portion 71 is formed with the same number of through holes 74 as the variable nozzle vane 61 and the linking member 63.The other end of each linking member 63 is inserted into a through hole 74 individually corresponding to the linking member 63 and is connected to the nozzle vane 61 individually corresponding to the linking member 63.

[0038] In a case where the annular member 62 is rotated to one side in the circumferential direction of the turbine wheel 3, the variable nozzle blades 61 adjacent to each other in the circumferential direction are moved (rotated) in a direction of separating from each other, and a flow path cross-sectional area of ​​the gas flow path 43A between the variable nozzle blades 61 is increased. Moreover, in a case where the annular member 62 is rotated to the other side in the circumferential direction of the turbine wheel 3, the variable nozzle blades 61 adjacent to each other in the circumferential direction are moved (rotated) in a direction of approaching each other, and the flow path cross-sectional area of ​​the gas flow path 43A between the variable nozzle blades 61 is reduced.

[0039] The variable nozzle unit 6 can adjust the flow path cross-sectional area of ​​the gas flow path 43A by transmitting a driving force from the outside (drive mechanism unit 65) of the variable nozzle unit 6 to the plurality of variable blades 61 via the annular member 62 and the plurality of linking members 63, so as to rotate the plurality of variable blades 61 around the rotation center RC of each of the variable blades 61 and change the blade angle of each of the variable blades 61. The turbine 2 can change a flow velocity and pressure of the exhaust gas supplied to the turbine wheel 3 by increasing or decreasing the flow path cross-sectional area of ​​the gas flow path 43A by means of the variable nozzle unit 6, and thus, boost pressure of the turbine 2 can be controlled. (preload element)

[0040] Fig. 4 is a schematic cross-sectional view illustrating a cross section along the axis line LA on one side with respect to the axis line LA of the turbine 2 according to an embodiment. As shown in Fig. 4, the turbine 2 further includes a biasing member 21 disposed between the second casing 5 and the first plate-like member 7 and configured to bias the first plate portion 71 toward one side of the gas flow path 43A.

[0041] At the Fig. In the embodiment shown in Fig. 4, the biasing member 21 includes a disc spring 21A that abuts against an end surface 52 formed on an inner side of the facing surface 51 of the second casing 5 in the radial direction, and an end surface 75A on a side opposite the first flow path wall surface 72 of an inner peripheral edge portion 75 of the first plate portion 71. The end surface 75A is formed on an inner side of the rear surface 73 in the radial direction. A space between the end surface 52 of the second casing 5 and the end surface 75A of the first plate portion 71 is sealed by the disc spring 21A (biasing member 21), and thus the inflow of the exhaust gas into the first space 43B from a rear surface side of the turbine wheel 3 is suppressed.

[0042] The first casing 4 includes a locked portion 44 extending along the radial direction of the turbine wheel 3 and to which an outer peripheral edge portion 76 of the first plate portion 71 is locked. The locked portion 44 has a rear scroll flow path wall surface 441 extending outward in the radial direction from a rear end P1 of the scroll flow path 41, and a locked surface 442 positioned on an opposite side in the axial direction from the rear scroll flow path wall surface 441 and facing the first space 43B.

[0043] The first plate-like member 7 is biased forward by the biasing member 21, so that the outer peripheral edge portion 76 of the first plate portion 71 is pressed against the locked portion 44 of the first housing 4, and a locking surface 76A on a front side of the outer peripheral edge portion 76 abuts against the locked surface 442. Accordingly, a space between the locking surface 76A and the locked surface 442 on the front side is sealed, and thus the inflow of the exhaust gas from the scroll flow path 41 into the first space 43B is suppressed. In the illustrated embodiment, the locking surface 76A is composed of a step surface formed on the outer side and the rear side of the first flow path wall surface 72 in the radial direction.Furthermore, in several other embodiments, the outer peripheral edge portion 76 of the first plate portion 71 may be clamped between the first housing 4 and the second housing 5.

[0044] At the Fig. 4, the first casing 4 includes a front-side facing surface 45 facing a second rear surface 83 of the second plate portion 81, and a shroud portion 46 projecting on an inner side of the second plate portion 81 and the front-side facing surface 45 in the radial direction rearward of the front-side facing surface 45. The shroud portion 46 has a shroud surface 46A curved in a convex shape so as to face a tip-side end (tip) of the plurality of turbine blades 32, and has a gap (clearance) between the tip-side end and the shroud surface 46A. (First embodiment)

[0045] As in Fig. 4, the turbine 2 according to some embodiments includes at least the above-mentioned turbine wheel 3, the first casing 4, the second casing 5, the first plate-like element 7, the second plate-like element 8, the biasing element 21, at least one variable nozzle blade 61, the annular element 62 and at least one linking element 63. As shown in Fig. 4, the turbine 2 further includes at least one positioning pin 9 and at least one stopper portion 22. It should be noted that the present embodiment can be implemented independently of other embodiments. (positioning pin)

[0046] As in Fig. 4, at least one positioning pin 9 has one end 91 thereof fitted (e.g., press-fitted) into a first hole 77 formed on the rear surface 73 of the first plate portion 71, and the other end 92 thereof fitted (e.g., press-fitted) into a second hole 53 formed on the facing surface 51 of the second casing 5. The positioning pin 9 is formed in a rod shape with a longitudinal direction along the axial direction of the turbine 2. The positioning pin 9 is formed, for example, from a metal material. In order to improve the assemblability of the turbine 2, the variable nozzle unit 6 is connected to the second casing 5 via the positioning pin 9, thereby preventing the variable nozzle unit 6 from falling off from the second casing 5. (Stopper section)

[0047] At least one stopper portion 22 is provided on the facing surface 51 or the first plate portion 71. As shown in Fig. 4, at least one stopper portion 22 may be configured integrally with the first plate portion 71 or may be configured integrally with the facing surface 51. Furthermore, at least one stopper portion 22 is a member different from the facing surface 51 or the first plate portion 71 and may be attached to the facing surface 51 or the first plate portion 71.

[0048] As in Fig. As shown in Figure 4, the turbine 2 has a first gap G1 formed between the stopper portion 22 and the facing surface 51 (illustrated example) or between the stopper portion 22 and the first plate portion 71. The first gap G1 is configured to be smaller than a second gap G2 between the annular member 62 and the facing surface 51 and a third gap G3 between the facing surface 51 and at least one linking member 63.

[0049] According to the above configuration, the first plate-like member 7 approaches one side of the second casing 5 due to thermal deformation during operation of the turbine 2, but the movement of the first plate-like member 7 toward the second casing 5 side can be restricted by causing the stopper portion 22 to abut against the facing surface 51 of the second casing 5 or the first plate portion 71. By restricting the movement of the first plate-like member 7 toward the second casing 5 side, it is possible to prevent the positioning pin 9 from being excessively inserted into the first hole 77 or the second hole 53 and from being stuck in the first hole 77 or the second hole 53.

[0050] Here, in a case where the turbine 2 does not include the stopper portion 22, there is a concern that the first plate-like member 7 approaches the second casing 5 side by more than the first gap G1 during operation of the turbine 2 due to thermal deformation.In this case, there is a concern that since the positioning pin 9 is excessively inserted into the first hole 77 or the second hole 53 and frictional resistance between the first hole 77 or the second hole 53 and the positioning pin 9 is increased, it is not possible to maintain a support structure of the variable nozzle unit 6 by means of a reaction force (a force for pushing back the first plate-like member 7 to a side of the gas flow path 43A) of the biasing member 21, and a gap may be generated between an outer peripheral edge portion 76 of the first plate-like member 7 and the locked portion 44 of the first housing 4, and the variable nozzle unit 6 may be lifted in the first space 43B. In this case, there is a concern that the variable nozzle unit 6 may be at risk of abrasion or the like due to vibration.

[0051] According to the above configuration, the movement of the first plate-like member 7 toward the second housing 5 side is restricted by the above-described stopper portions 22, and thus, it is possible to prevent the positioning pin 9 from getting stuck in the first hole 77 or the second hole 53 and inhibit the reaction force of the biasing member 21. In this case, the support structure of the variable nozzle unit 6 (first plate-like member 7) can be stably maintained by the reaction force of the biasing member 21. By stably maintaining the support structure of the variable nozzle unit 6, a risk of abrasion or the like due to vibration of the variable nozzle unit 6 can be reduced.

[0052] In some embodiments, the at least one stopper portion 22 described above is configured integrally with the first plate-like member 7. In this case, compared to a case where the stopper portion 22 is a member different from the first plate-like member 7 or the second casing 5, it is possible to suppress an increase in the number of components and suppress an increase in the complexity of the structure of the turbine 2. Moreover, in a case where the stopper portion 22 is configured integrally with the second casing 5, there is a concern that the stopper portion 22 will interfere with the variable nozzle unit 6 when the variable nozzle unit 6 is mounted to the second casing 5. However, in a case where the stopper portion 22 is configured integrally with the first plate-like member 7, there is relatively little concern that the stopper portion 22 will interfere with the variable nozzle unit 6.Moreover, forming the stopper portion 22 on the first plate-like member 7 is easier than forming the stopper portion 22 on the second housing 5.

[0053] In some embodiments, as in Fig. 3 and Fig. 4, the first plate-like member 7 described above includes a tubular portion 78 protruding from the rear surface 73 of the first plate portion 71 and inserted into a center hole of the annular member 62, and at least one claw portion 22A protruding from the tubular portion 78 to the outer peripheral side of the inner peripheral edge of the annular member 62, with the inner peripheral edge of the annular member 62 being sandwiched between the rear surface 73 of the first plate portion 71 and the claw portion 22A. The above-described at least one stopper portion 22 includes at least one claw portion 22A. That is, the claw portion 22A of the first plate-like member 7 is used as the stopper portion 22.

[0054] At the Fig. 3, the at least one claw portion 22A includes a plurality of (three in the illustrated example) claw portions 22A arranged at intervals along the circumferential direction of the turbine wheel 3. Recessed portions 622 are formed on the inner peripheral edge of the annular member 62 in the same number as the number of claw portions 22A to allow the claw portions 22A to pass in a case where the first plate-like member 7 and the annular member 62 are assembled.

[0055] According to the above configuration, by using at least one claw portion 22A that clamps the inner peripheral edge of the annular member 62 as the stopper portion 22, it is not necessary to newly provide a stopper portion protrusion on the first plate-like member 7. Therefore, it is possible to reduce the number of changes to the existing shape of the first plate-like member 7 and reduce the complexity of the structure of the first plate-like member 7.

[0056] At the Fig. 4 and Fig. 5, the above-described second housing 5 has a protruding portion 54 that protrudes forward from the facing surface 51 along the axial direction of the turbine wheel 3. The protruding portion 54 may be formed in an arcuate shape or a ring shape extending along the circumferential direction of the turbine wheel 3. In the turbine 2, a fourth gap G4 is formed between an end surface 54A of the protruding portion 54 on the front side in the axial direction and the rear surface 73 of the first plate portion 71. In the embodiments shown in Fig. 4 and Fig. In the embodiments illustrated in FIG. 5, the protrusion portion 54 (end surface 54A) is a part of the facing surface 51, is formed on the inner side in the radial direction from an outer peripheral edge portion of the facing surface 51 where the protrusion portion 54 is not formed, and is formed on the outer side in the radial direction from the above-described end surface 52. The rear surface 73 of the first plate portion 71 includes an inner peripheral side rear surface 73A formed at an inner peripheral edge portion thereof, which forms the fourth gap G4 between the end surface 54A and the rear surface 73 of the first plate portion 71.

[0057] At the Fig. 4, the above-described fourth gap G4 is configured to be larger than the above-described second gap G2 and the above-described third gap G3.

[0058] For some in Fig. 5, the above-described fourth gap G4 is configured to be smaller than the above-described second gap G2 and the above-described third gap G3. In this case, the projection portion 54 can be used as the stopper portion 22. That is, in the embodiment shown in Fig. In the embodiment illustrated in Figure 5, the at least one stopper portion 22 described above is a protrusion portion 54 configured integrally with the second housing 5. The fourth gap G4 is the first gap G1 described above.

[0059] According to the above configuration, by using the protrusion portion 54 as the stopper portion 22, it is not necessary to newly provide a stopper portion protrusion on the second housing 5. Therefore, it is possible to reduce the number of changes to the existing shape of the second housing 5 and reduce the complexity of the structure of the second housing 5. (Second embodiment)

[0060] Fig. 5 is a schematic cross-sectional view illustrating a cross section along the axis line LA on one side with respect to the axis line LA of the turbine 2 according to an embodiment. As shown in Fig. 5, the turbine 2 according to some embodiments includes at least the above-mentioned turbine wheel 3, the first casing 4, the second casing 5, the first plate-like element 7, the second plate-like element 8, the biasing element 21 and at least one variable nozzle blade 61. As shown in Fig. As shown in Figure 5, the turbine 2 further includes at least one positioning pin 9 and an adhesive layer 94. It should be noted that the present embodiment can be implemented independently of other embodiments. For example, the turbine 2 may not include the stopper portion 22 described above. (positioning pin)

[0061] As in Fig. As shown in FIG. 5, at least one positioning pin 9 has one end 91 thereof inserted into a first hole 77 formed on the rear surface 73 of the first plate portion 71, and the other end 92 thereof inserted into a second hole 53 formed on the facing surface 51 of the second casing 5. At least one of the one end 91 and the other end 92 of the positioning pin 9 is inserted in a state of having gaps 93A and 93B. The positioning pin 9 is formed in a rod shape having a longitudinal direction along the axial direction of the turbine 2. The positioning pin 9 is formed of, for example, a metal material. In the illustrated embodiment, one end 91 of the positioning pin 9 is loosely inserted into the first hole 77, and a gap 93A is formed between an outer peripheral surface of the one end 91 and an inner peripheral surface of the first hole 77.In addition, the other end 92 of the positioning pin 9 is loosely inserted into the second hole 53, and a gap 93B is formed between the outer peripheral surface of the other end 92 and the inner peripheral surface of the second hole 53. (adhesive layer)

[0062] The adhesive layer 94 is inserted into at least one of the gap 93A and the gap 93B. In the illustrated embodiment, the adhesive layer 94 is inserted into both the gap 93A and the gap 93B. The adhesive layer 94 is configured to have reduced adhesive strength due to heat input during operation of the turbine 2. Since the gap 93A is more affected by heat input than the gap 93B during operation of the turbine 2, in a case where the adhesive layer 94 is inserted into the gap 93A or the gap 93B, it is preferable to insert the adhesive layer 94 into the gap 93A. The decrease in the adhesive strength of the adhesive layer 94 may be temporary or permanent during operation of the turbine 2. In a case where the variable nozzle unit 6 is connected to the second housing 5 via the positioning pin 9 and the adhesive layer 94, the adhesive strength of the adhesive layer 94 is not reduced.Therefore, the variable nozzle unit 6 is prevented from falling off the second housing 5.

[0063] According to the above configuration, since the adhesive strength of the adhesive layer 94 is reduced due to heat input during operation of the turbine 2, a gap is generated between at least one of the first hole 77 or the second hole 53 and the positioning pin 9. Therefore, it is possible to prevent the positioning pin 9 from getting stuck in the first hole 77 or the second hole 53 when the first plate-like member 7 approaches the second casing 5 side due to thermal deformation during operation of the turbine 2. By preventing the positioning pins 9 from getting stuck in the first holes 77 or the second holes 53 and inhibiting the reaction force of the biasing member 21, the support structure of the variable nozzle unit 6 (first plate-like member 7) can be stably maintained by the reaction force of the biasing member 21.By stably maintaining the support structure of the variable nozzle unit 6, a risk of abrasion or the like due to vibration of the variable nozzle unit 6 can be reduced.

[0064] In some embodiments, the adhesive layer 94 described above is formed from a thermoplastic resin material. The thermoplastic resin material may, for example, include at least one of a phenoxy resin, a polyurethane resin, a polyesterurea resin, a butyral resin, an acrylic resin, a polyimide resin, and a polyamide resin.

[0065] According to the above configuration, the adhesive strength of the adhesive layer 94 is reduced by softening (e.g., liquefaction) of the adhesive layer 94 formed of the thermoplastic resin material due to heat input during the operation of the turbine 2, and thus the gaps 93A, 93B between at least one of the first hole 77 or the second hole 53 and the positioning pin 9 can be effectively generated. (Third embodiment)

[0066] Fig. 6 is a schematic cross-sectional view illustrating a cross section along the axis line LA on one side with respect to the axis line LA of the turbine 2 according to an embodiment. As shown in Fig. 6, the turbine 2 according to some embodiments includes at least the above-mentioned turbine wheel 3, the first casing 4, the second casing 5, the first plate-like element 7, the second plate-like element 8, the biasing element 21 and at least one variable nozzle blade 61. As shown in Fig. As shown in Figure 6, the turbine 2 further includes at least one positioning pin 9 and a sliding layer 95. It should be noted that the present embodiment can be implemented independently of other embodiments. For example, the turbine 2 may not include the stopper portion 22 described above. (positioning pin)

[0067] As in Fig. As shown in Fig. 6, at least one positioning pin 9 has one end 91 thereof inserted into a first hole 77 formed on the rear surface 73 of the first plate portion 71, and the other end 92 thereof inserted into a second hole 53 formed on the facing surface 51 of the second casing 5. The positioning pin 9 is formed in a rod shape with a longitudinal direction along the axial direction of the turbine 2. The positioning pin 9 is formed, for example, from a metal material. (sliding layer)

[0068] The sliding layer 95 contains a solid lubricant covering at least one of an outer peripheral surface 911 of one end 91 of the at least one positioning pin 9, an outer peripheral surface 921 of the other end 92 of the at least one positioning pin 9, an inner peripheral surface 771 of the first hole 77, and an inner peripheral surface 531 of the second hole 53. The sliding layer 95 can be formed by applying or coating the solid lubricant onto a target object, such as the outer peripheral surfaces 911 and 921 of the positioning pin 9, the inner peripheral surface 771 of the first hole 77, or the inner peripheral surface 531 of the second hole 53. The solid lubricant can contain at least one of molybdenum disulfide, graphite, and polytetrafluoroethylene (PTFE).

[0069] In the illustrated embodiment, the sliding layer 95 includes a first-hole-side sliding layer 95A covering at least one of the outer peripheral surface 911 of one end 91 of the positioning pin 9 and the inner peripheral surface 771 of the first hole 77, and a second-hole-side sliding layer 95B covering at least one of the outer peripheral surface 921 of the other end 92 of the positioning pin 9 and the inner peripheral surface 531 of the second hole 53. The sliding layer 95 can be provided over the entire length of the positioning pin 9. The first-hole-side sliding layer 95A reduces the frictional resistance between the outer peripheral surface 911 of one end 91 of the positioning pin 9 and the inner peripheral surface 771 of the first hole 77.The frictional resistance between the outer peripheral surface 921 of the other end 92 of the positioning pin 9 and the inner peripheral surface 531 of the second hole 53 is reduced by the sliding layer 95B on the second hole side.

[0070] According to the above configuration, since the sliding layer 95 reduces the frictional resistance between at least one of the first hole 77 and the second hole 53 and the positioning pin 9, in a case where the first plate-like member 7 approaches the second casing 5 side due to thermal deformation during operation of the turbine 2, it is possible to prevent the positioning pin 9 from getting stuck in the first hole 77 or the second hole 53. By preventing the positioning pins 9 from getting stuck in the first holes 77 or the second holes 53 and inhibiting the reaction force of the biasing member 21, the support structure of the variable nozzle unit 6 and the first plate-like member 7 can be stably maintained by the reaction force of the biasing member 21.By stably maintaining the support structure of the variable nozzle unit 6, a risk of abrasion or the like due to vibration of the variable nozzle unit 6 can be reduced.

[0071] Fig. 7 is a schematic cross-sectional view illustrating a cross section along the axis line LA on one side with respect to the axis line LA of the turbine 2 according to an embodiment. Fig. 8 is an explanatory diagram for describing a side S1 near the tongue portion and a side S2 away from the tongue portion. Fig. Figure 9 is a schematic view of a variable nozzle unit 6 provided in the turbine 2 according to an embodiment. In some embodiments, as shown in Fig. 9, at least one of the first hole 77 and the second hole 53 described above has a longitudinal direction along the radial direction of the turbine wheel 3.

[0072] The first plate portion 71 in which the first hole 77 is formed and the second casing 5 in which the second hole 53 is formed have a difference in thermal expansion amount during operation of the turbine 2, and a shearing force due to the difference in thermal expansion amount between the first plate portion 71 and the second casing 5 acts on the positioning pin 9.

[0073] According to the above configuration, by setting a hole shape of the first hole 77 or the second hole 53 to have a longitudinal direction along the radial direction of the turbine wheel 3, the positioning pin 9 does not restrict thermal expansion between the first plate portion 71 and the second housing 5, as compared with a case where the first hole 77 or the second hole 53 is a round hole (see Fig. 3). Therefore, it is possible to suppress the occurrence of excessive load between the positioning pin 9 and the first hole 77 or between the positioning pin 9 and the second hole 53, and thus it is possible to effectively prevent the positioning pin 9 from getting stuck in the first hole 77 or the second hole 53. Moreover, according to the above configuration, since it is possible to reduce the shearing force acting on the positioning pin 9 due to the difference in thermal expansion amount between the first plate portion 71 and the second housing 5, it is possible to effectively prevent the positioning pin 9 from getting stuck in the first hole 77 or the second hole 53.

[0074] As in Fig. As shown in Fig. 7, the second plate-like member 8 may include the above-described second plate portion 81, a shroud surface 84 formed at an inner peripheral end portion of the second plate portion 81, and a tubular portion 85 protruding forward from the inner peripheral end portion of the second plate portion 81 along the axial direction of the turbine wheel 3. The shroud surface 84 is curved in a convex shape so as to face a tip-side end (tip) of the plurality of turbine blades 32, and has a gap (clearance) between the tip-side end and the shroud surface 84.The first housing 4 may include the front facing surface 45 facing the second rear surface 83 of the second plate portion 81, and a step portion 47 continuous with the inner peripheral end of the front facing surface 45 and receiving the tubular portion 85 of the second plate-like member 8.

[0075] As in Fig. 8, a tongue portion 48 of the screw flow path 41 is formed between the beginning and the end of the winding of the screw flow path 41. As shown in Fig. 8, in a cross section of the turbine wheel 3 perpendicular to the axial direction, a first reference line, which is a straight line passing through the axis line LA of the turbine wheel 3 and the tongue portion 48, is defined as BL1, and a second reference line, which is a straight line passing through the axis line LA of the turbine wheel 3 and perpendicular to the first reference line BL1, is defined as BL2. A side on which the tongue portion 48 is positioned with respect to the second reference line BL2 is defined as a tongue portion near side S1, and a side separated from the tongue portion 48 with respect to the second reference line BL2 is defined as a tongue portion away side S2.

[0076] In some embodiments, as in Fig. 9, the at least one positioning pin 9 described above comprises a plurality of positioning pins 9 arranged at intervals along the circumferential direction of the turbine wheel 3. As shown in Fig. 9, in a cross section perpendicular to the axis line LA of the turbine wheel 3, a point CP at which the distances from respective center positions LD (for example, a center of gravity) of the plurality of positioning pins 9 are equal is arranged to be shifted to a tongue portion side of the scroll flow path 41 (side S1 near the tongue portion) with respect to the axis line LA of the turbine wheel 3.

[0077] On the tongue portion near side S1, the one side closer to the tongue portion 48 of the scroll flow path 41 than to the axis line LA of the turbine wheel 3 of the variable nozzle unit 6, the temperature of gas flowing in the scroll flow path 41 is higher than that on the tongue portion away side S2, the one side opposite to the tongue portion 48 and farther away than from the axis line LA of the turbine wheel 3. Therefore, there is a concern that a difference in thermal expansion amount due to heat input from the gas flowing in the scroll flow path 41 between the tongue portion near side S1 and the tongue portion away side S2 is large, and a core deviation amount of the axis line LB of the variable nozzle unit 6 with respect to the axis line LA of the turbine wheel 3 is increased.

[0078] In the Fig. 4 and Fig. 7, in a case where the axis line LB of the variable nozzle unit 6 deviates from the axis line LA of the turbine wheel 3, there is a concern that an inner peripheral end portion of the first plate-like member 7 may come into contact with the second housing 5. In addition, in the embodiment shown in Fig. 7, there is a concern that an inner peripheral end portion of the second plate-like member 8 may come into contact with the turbine wheel 3.

[0079] According to the above configuration, by eccentrically arranging the point CP (center point between pins, center of gravity), at which the distances from the respective center positions LD of the plurality of positioning pins 9 are equal, to the S1 side near the tongue portion with respect to the axis line LA of the turbine wheel 3, the positioning pins 9 on the S1 side near the tongue portion can suppress the thermal expansion of the S1 side near the tongue portion, compared to a case where the center point CP between the pins is either aligned with the axis line LA of the turbine wheel 3 or eccentrically arranged toward the S2 side away from the tongue portion. Therefore, the difference in thermal expansion amount between the S1 side near the tongue portion and the S2 side away from the tongue portion can be reduced, and the increase in the core deviation amount of the axis line LB of the variable nozzle unit 6 with respect to the axis line LA of the turbine wheel 3 can be suppressed.In this case, it is possible to suppress the contact of the variable nozzle unit 6 with the first housing 4, the second housing 5, or the turbine wheel 3 due to the core deviation of the axis line LB of the variable nozzle unit 6 with respect to the axis line LA of the turbine wheel 3, and it is possible to suppress the excessive contact load acting on the positioning due to the contact. By suppressing the effect of the excessive contact load on the positioning, it is possible to effectively prevent the positioning pins 9 from getting stuck in the first holes 77 or the second holes 53.

[0080] Fig. 10 is a schematic cross-sectional view illustrating a cross section along the axis line LA on one side with respect to the axis line LA of the turbine 2 according to an embodiment. In some embodiments, as shown in Fig. 10, the above-mentioned biasing member 21 (21B) includes at least a first biasing plate portion 211 extending along a radial direction of the turbine wheel 3 and abutting against the second casing 5, and a second biasing plate portion 212 extending along the radial direction and abutting against the first plate-like member 7.

[0081] In the illustrated embodiment, the first preload plate portion 211 and the second preload plate portion 212 are formed in an annular shape extending along the circumferential direction of the turbine wheel 3. An outer peripheral edge portion of the first preload plate portion 211 abuts the end surface 52 of the second casing 5, and an outer peripheral edge portion of the second preload plate portion 212 abuts the end surface 75A of the first plate portion 71. The preload member 21 (21B) has an opening outward in the radial direction of the turbine wheel 3. In the embodiment shown in Fig. In the embodiment shown in Fig. 10, the cross-sectional shape of the biasing element 21 (21B) is formed in a V-shape.

[0082] According to the above configuration, the biasing member 21 (21B) including the first biasing plate portion 211 and the second biasing plate portion 212 can increase the pressing force (reaction force) on the first plate portion 71 compared to a case where a single plate member such as a disc spring 21A abuts the second housing 5 and the first plate-like member 7. By increasing the pressing force (reaction force) of the biasing member 21 (21B) on the first plate portion 71, the support structure of the variable nozzle unit 6 (first plate-like member 7) can be maintained more stably.

[0083] As in Fig.1, the turbocharger 1 according to some embodiments includes the above-described turbine 2 and the above-described centrifugal compressor 12. In this case, since the support structure of the variable nozzle unit 6 (first plate-like member 7) can be stably maintained and the risk of abrasion or the like due to vibration of the variable nozzle unit 6 can be reduced, the reliability of the turbocharger 1 can be improved.

[0084] In the present specification, 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 shifted by an angle or a distance, as far as the same function can be obtained.

[0085] 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 long as the same function can be maintained.

[0086] Moreover, in the present specification, a term representing a shape such as a quadrangular shape or a cylindrical shape represents not only a shape such as a quadrangular shape or a cylindrical shape in a geometrically strict sense, but also a shape including an uneven portion, a chamfer portion, and the like within a range where the same effect can be obtained.

[0087] Furthermore, in this specification, terms such as “comprising,” “containing,” or “having” a component are not exclusive terms that exclude the presence of other components.

[0088] The present disclosure is not limited to the above-described embodiments and includes a modification of the above-described embodiments and an appropriate combination of the embodiments.

[0089] For example, contents described in some of the embodiments described above are understood as follows. (1) A turbine (2) according to at least one embodiment of the present disclosure comprises: a first housing (4) having a screw flow path (41); a turbine wheel (3) provided on an inner peripheral side of the screw flow path (41); a first plate-like member (7) including an annular first plate portion (71); a second plate-like member (8) including an annular second plate portion (81) disposed to face the first plate portion (71) and forming a gas flow path (43A) between the first plate portion (71) and the second plate portion (81) from the scroll flow path (41) to the turbine wheel (3); at least one variable nozzle vane (61) arranged in the gas flow path (43A); a second housing (5) having a facing surface (51) opposite to a rear surface (73) of the first plate portion (71) on a side opposite to a flow path wall surface (72) facing the gas flow path (43A), with a first space (43B) interposed therebetween; an annular member (62) disposed in the first space (43B) and configured to rotate with respect to the first plate-like member (7) by means of an external driving force; at least one linking member (63) having one end connected to the annular member (62) and the other end connected to the variable nozzle vane (61), which changes a vane angle of the variable nozzle vane (61) connected to the other end in conjunction with the rotation of the annular member (62); a biasing member (21) disposed between the second housing (5) and the first plate-like member (7) and configured to bias the first plate portion (71) toward one side of the gas flow path (43A); at least one positioning pin (9), one end (91) of which is fitted into a first hole (77) formed on the rear surface (73) of the first plate portion (71) and the other end (92) of which is fitted into a second hole (53) formed on the facing surface (51) of the second housing (5); and at least one stopper portion (22) provided on the facing surface (51) or the first plate portion (71), wherein a first gap (G1) is formed between the stopper portion (22) and the facing surface (51) or between the stopper portion (22) and the first plate portion (71), and the first gap (G1) is smaller than a second gap (G2) between the annular element (62) and the facing surface (51) and a third gap (G3) between the at least one linking element (63) and the facing surface (51).

[0090] According to the configuration of the above 1), the first plate-like member (7) approaches one side of the second casing (5) due to thermal deformation during operation of the turbine (2), but the movement of the first plate-like member (7) toward the second casing (5) side can be restricted by causing the stopper portion (22) to abut against the facing surface (51) of the second casing (5) or the first plate portion (71). By restricting the movement of the first plate-like member (7) toward the second casing (5) side, it is possible to prevent the positioning pin (9) from being excessively inserted into the first hole (77) or the second hole (53) and from getting stuck in the first hole (77) or the second hole (53).By preventing the positioning pins (9) from getting stuck in the first holes (77) or the second holes (53) and inhibiting the reaction force of the biasing member (21), the support structure of the variable nozzle unit (6) (the first plate-like member (7)) can be stably maintained by the reaction force of the biasing member (21). By stably maintaining the support structure of the variable nozzle unit (6), a risk of abrasion or the like due to vibration of the variable nozzle unit (6) can be reduced.

[0091] 2) In some embodiments, in the turbine (2) according to the above 1), the at least one stopper portion (22) is configured integrally with the first plate-like element (7).

[0092] According to the configuration of the above 2), compared to a case where the stopper portion (22) is a member different from the first plate-like member (7) or the second casing (5), it is possible to suppress an increase in the number of components and suppress an increase in the complexity of the structure of the turbine (2). Moreover, in a case where the stopper portion (22) is configured integrally with the second casing (5), there is a concern that the stopper portion (22) will interfere with the variable nozzle unit (6) when the variable nozzle unit (6) is mounted on the second casing (5). However, in a case where the stopper portion (22) is configured integrally with the first plate-like member (7), there is relatively little concern that the stopper portion (22) will interfere with the variable nozzle unit (6).Moreover, forming the stopper portion (22) on the first plate-like member (7) is easier than forming the stopper portion (22) on the second housing (5).

[0093] 3) In some embodiments, in the turbine (2) according to the above 1) or 2), the first plate-like member (7) includes a tubular portion (78) protruding from the back surface (73) of the first plate portion (71) and inserted into a center hole of the annular member (62), and at least one claw portion (22A) protruding from the tubular portion (78) to an outer peripheral side of an inner peripheral edge of the annular member (62), the inner peripheral edge of the annular member (62) being interposed between the back surface (73) of the first plate portion (71) and the claw portion (22A), and the at least one stopper portion (22) includes the at least one claw portion (22A).

[0094] According to the configuration of the above 3), by using at least one claw portion (22A) that clamps the inner peripheral edge of the annular member (62) as the stopper portion (22), it is not necessary to newly provide a stopper portion (protrusion) on the first plate-like member (7). Therefore, it is possible to reduce the number of changes to the existing shape of the first plate-like member (7) and reduce the complexity of the structure of the first plate-like member (7).

[0095] 4) A turbine (2) according to at least one embodiment of the present disclosure comprises: a first housing (4) having a screw flow path (41); a turbine wheel (3) provided on an inner peripheral side of the screw flow path (41); a first plate-like member (7) including an annular first plate portion (71); a second plate-like member (8) including an annular second plate portion (81) disposed to face the first plate portion (71) and forming a gas flow path (43A) between the first plate portion (71) and the second plate portion (81) from the scroll flow path (41) to the turbine wheel (3); at least one variable nozzle vane (61) arranged in the gas flow path (43A); a second housing (5) having a facing surface (51) opposite to a rear surface (73) of the first plate portion (71) on a side opposite to a flow path wall surface (72) facing the gas flow path (43A), with a first space (43B) interposed therebetween; a biasing member (21) disposed between the second housing (5) and the first plate-like member (7) and configured to bias the first plate portion (71) toward one side of the gas flow path (43A); at least one positioning pin (9), one end (91) of which is inserted into a first hole (77) formed on the rear surface (73) of the first plate portion (71) and the other end (92) of which is inserted into a second hole (53) formed on the facing surface (51) of the second housing (5), in a state in which at least one of the one end (91) and the other end (92) has a gap (93A, 93B); and an adhesive layer (94) which is inserted in the gap (93A, 93B) and of which an adhesive strength decreases due to heat input during operation of the turbine (2).

[0096] According to the configuration of the above 4), since the adhesive strength of the adhesive layer (94) is reduced due to heat input during operation of the turbine (2), a gap is generated between at least one of the first hole (77) or the second hole (53) and the positioning pin (9). Therefore, it is possible to prevent the positioning pin (9) from getting stuck in the first hole (77) or the second hole (53) in a case where the first plate-like member (7) approaches the second casing (5) side due to thermal deformation during operation of the turbine (2). By preventing the positioning pins (9) from getting stuck in the first holes (77) or the second holes (53) and inhibiting the reaction force of the biasing member (21), the support structure of the variable nozzle unit (6) (the first plate-like member (7)) can be stably maintained by the reaction force of the biasing member (21).By stably maintaining the support structure of the variable nozzle unit (6), a risk of abrasion or the like due to vibration of the variable nozzle unit (6) can be reduced.

[0097] 5) In some embodiments, in the turbine (2) according to the above 4), the adhesive layer (94) is formed of a thermoplastic resin material.

[0098] According to the configuration of the above 5), the adhesive strength of the adhesive layer (94) is reduced by softening (for example, liquefying) the adhesive layer (94) formed of the thermoplastic resin material due to heat input during the operation of the turbine (2), and thus the gaps (93A, 93B) between at least one of the first hole (77) or the second hole (53) and the positioning pin (9) can be effectively created.

[0099] 6) A turbine (2) according to at least one embodiment of the present disclosure comprises: a first housing (4) having a screw flow path (41); a turbine wheel (3) provided on an inner peripheral side of the screw flow path (41); a first plate-like member (7) including an annular first plate portion (71); a second plate-like member (8) including an annular second plate portion (81) disposed to face the first plate portion (71) and forming a gas flow path (43A) between the first plate portion (71) and the second plate portion (81) from the scroll flow path (41) to the turbine wheel (3); at least one variable nozzle vane (61) arranged in the gas flow path (43A); a second housing (5) having a facing surface (51) opposite to a rear surface (73) of the first plate portion (71) on a side opposite to a flow path wall surface (72) facing the gas flow path (43A), with a first space (43B) interposed therebetween; a biasing member (21) disposed between the second housing (5) and the first plate-like member (7) and configured to bias the first plate portion (71) toward one side of the gas flow path (43A); at least one positioning pin (9), one end (91) of which is inserted into a first hole (77) formed on the rear surface (73) of the first plate portion (71) and the other end (92) of which is inserted into a second hole (53) formed on the facing surface (51) of the second housing (5); and a sliding layer (95) containing a solid lubricant covering at least one of an outer peripheral surface (911) of one end (91) of the at least one positioning pin (9), an outer peripheral surface (921) of the other end (92) of the at least one positioning pin (9), an inner peripheral surface (771) of the first hole (77), and an inner peripheral surface (531) of the second hole (53).

[0100] According to the configuration of the above 6), since the sliding layer (95) reduces the frictional resistance between at least one of the first hole (77) and the second hole (53) and the positioning pin (9), in a case where the first plate-like member (7) approaches the side of the second casing (5) due to thermal deformation during operation of the turbine (2), it is possible to prevent the positioning pin (9) from getting stuck in the first hole (77) or the second hole (53). By preventing the positioning pins (9) from getting stuck in the first holes (77) or the second holes (53) and inhibiting the reaction force of the biasing member (21), the support structure of the variable nozzle unit (6) (the first plate-like member (7)) can be stably maintained by the reaction force of the biasing member (21).By stably maintaining the support structure of the variable nozzle unit (6), a risk of abrasion or the like due to vibration of the variable nozzle unit (6) can be reduced.

[0101] 7) In some embodiments, in the turbine (2) according to any one of 1) to 6) above, at least one of the first hole (77) and the second hole (53) has a longitudinal direction along a radial direction of the turbine wheel (3).

[0102] The first plate portion (71) in which the first hole (77) is formed and the second casing (5) in which the second hole (53) is formed have a difference in thermal expansion amount during operation of the turbine (2), and a shear force due to the difference in thermal expansion amount between the first plate portion (71) and the second casing (5) acts on the positioning pin (9). According to the configuration of the above 7), by setting a hole shape of the first hole (77) or the second hole (53) to have a longitudinal direction along the radial direction of the turbine wheel (3), the positioning pin (9) does not limit thermal expansion between the first plate portion (71) and the second casing (5), compared to a case where the first hole (77) or the second hole (53) is a round hole.Therefore, it is possible to suppress the occurrence of an excessive load between the positioning pin (9) and the first hole (77) or between the positioning pin (9) and the second hole (53), and thus it is possible to effectively prevent the positioning pin (9) from getting stuck in the first hole (77) or the second hole (53). Furthermore, according to the configuration of the above 7), since it is possible to reduce the shearing force due to the difference in thermal expansion amount between the first plate portion (71) and the second housing (5) acting on the positioning pin (9), it is possible to effectively prevent the positioning pin (9) from getting stuck in the first hole (77) or the second hole (53).

[0103] 8) In some embodiments, in the turbine (2) according to any one of the above 1) to 7), the at least one positioning pin (9) includes a plurality of positioning pins (9) arranged at intervals along a circumferential direction of the turbine wheel (3), and in a cross section perpendicular to an axis line (LA) of the turbine wheel (3), a point (CP) at which distances from respective center positions (LD) of the plurality of positioning pins (9) are equal is arranged to be shifted to a tongue portion (S1) side of the scroll flow path (41) with respect to the axis line (LA) of the turbine wheel (3).

[0104] On the tongue portion near side (S1), which is a side closer to the tongue portion (48) of the scroll flow path (41) than to the axis line (LA) of the turbine wheel (3) of the variable nozzle unit (6), the temperature of gas flowing in the scroll flow path (41) is higher than that on the tongue portion away side (S2), which is a side opposite to the tongue portion (48) and farther away than from the axis line (LA) of the turbine wheel (3). Therefore, there is a concern that a difference of thermal expansion amount due to heat input from the gas flowing in the scroll flow path (41) between the side (S1) near the tongue portion and the side (S2) away from the tongue portion is large and a core deviation amount of the axis line (LB) of the variable nozzle unit (6) with respect to the axis line (LA) of the turbine wheel (3) is increased.

[0105] According to the configuration of the above 8), by eccentrically disposing the point (CP, center point between pins, center of gravity) at which the distances from the respective center positions (LD) of the plurality of positioning pins (9) are equal to the tongue portion near side (S1) with respect to the axis line (LA) of the turbine wheel (3), the positioning pins (9) on the tongue portion near side (S1) can suppress the thermal expansion of the tongue portion near side (S1) compared to a case where the center point (CP) between the pins is either aligned with the axis line (LA) of the turbine wheel (3) or eccentrically disposed to the side (S2) away from the tongue portion.Therefore, the difference in thermal expansion amount between the side (S1) near the tongue portion and the side (S2) away from the tongue portion can be reduced, and the increase in the core deviation amount of the axis line (LB) of the variable nozzle unit (6) with respect to the axis line (LA) of the turbine wheel (3) can be suppressed. In this case, it is possible to suppress the contact of the variable nozzle unit (6) with the first housing (4), the second housing (5), or the turbine wheel (3) due to the core deviation of the axis line (LB) of the variable nozzle unit (6) with respect to the axis line (LA) of the turbine wheel (3), and it is possible to suppress the excessive contact load acting on the positioning due to the contact. By suppressing the effect of the excessive contact load on the positioning, it is possible to effectively prevent the positioning pins (9) from getting stuck in the first holes (77) or the second holes (53).

[0106] 9) In some embodiments, in the turbine (2) according to any one of 1) to 8) above, the biasing member (21(21B)) includes at least a first biasing plate portion (211) extending along a radial direction of the turbine wheel (3) and abutting against the second casing (5), and a second biasing plate portion (212) extending along the radial direction and abutting against the first plate-like member (7).

[0107] According to the configuration of the above 9), the biasing member (21 (21B)) including the first biasing plate portion (211) and the second biasing plate portion (212) can increase the pressing force (reaction force) on the first plate portion (71) compared to a case where a single plate member such as a disc spring (21A) abuts against the second housing (5) and the first plate-like member (7). By increasing the pressing force (reaction force) of the biasing member (21 (21B)) on the first plate portion (71), the support structure of the variable nozzle unit (6) (the first plate-like member (7)) can be maintained more stably.

[0108] 10) A turbocharger (1) according to at least one embodiment of the present disclosure comprises: the turbine (2) according to one of the above 1) to 9); and a centrifugal compressor (12) configured to be driven by the turbine (2).

[0109] According to the configuration of the above 10), since the support structure of the variable nozzle unit (6) (the first plate-like member (7)) can be stably maintained and the risk of abrasion or the like due to vibration of the variable nozzle unit (6) can be reduced, the reliability of the turbocharger (1) can be improved. List of reference symbols 1 turbocharger 2 turbines 3 Turbine wheel 4 first housing 5 second housing 6 variable nozzle unit 7 first plate-like element 8 second plate-like element 9 Positioning pin 10 Internal combustion engine system 11 Internal combustion engine 12 Centrifugal compressor 13 Wheel 14 Compressor housing 15 Rotating shaft 16 warehouses 21 Preload element 21A disc spring 22 stopper section 22A Claw section 31 Hub 32 turbine blades 41 Screw flow path 42 Exhaust gas discharge flow path 43 Interior 43A Gas flow path 43B first room 44 locked section 45, 51 facing surface 46 Sheathing section 46A, 84 sheathing surface 47 step section 48 Tongue section 52, 75A end face 53 second hole 54 projection section 61 variable nozzle vane 62 ring-shaped element 63 Linking element 64 Support element 65 Drive mechanism unit 71 first plate section 72 first flow path wall surface 73 back surface 74 through hole 75 inner peripheral edge section 76 Outer peripheral edge section 76A locking surface 77 first hole 78, 85 tubular section 81 second plate section 82 second flow path wall surface 83 second back surface 93A, 93B gap 94 Adhesive layer 95 Sliding layer 95A Sliding layer on side of first hole 95B Sliding layer on side of second hole BL1 first reference line BL2 second reference line CP center point G1 first gap G2 second slit G3 third slit G4 fourth slit LA axis line LD middle position P1 rear end S1 side near tongue section S2 side away from tongue section 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 2013-072401

[0004]

Claims

[1] Turbine, comprising: a first housing having a screw flow path; a turbine wheel provided on an inner peripheral side of the screw flow path; a first plate-like member including an annular first plate portion; a second plate-like member including an annular second plate portion disposed to face the first plate portion and forming a gas flow path between the first plate portion and the second plate portion from the scroll flow path toward the turbine wheel; at least one variable nozzle vane arranged in the gas flow path; a second housing having a facing surface opposite to a rear surface of the first plate portion on a side opposite to a flow path wall surface facing the gas flow path, with a first space interposed therebetween; an annular member disposed in the first space and configured to rotate with respect to the first plate-like member by means of an external driving force; at least one linking member, one end of which is connected to the annular member and the other end of which is connected to the variable nozzle vane, which changes a vane angle of the variable nozzle vane connected to the other end in conjunction with the rotation of the annular member; a biasing member disposed between the second housing and the first plate-like member and configured to bias the first plate portion toward one side of the gas flow path; at least one positioning pin, one end of which is fitted into a first hole formed on the rear surface of the first plate portion and the other end of which is fitted into a second hole formed on the facing surface of the second housing; and at least one stopper portion provided on the facing surface or the first plate portion, wherein a first gap is formed between the stopper portion and the facing surface or between the stopper portion and the first plate portion, the first gap being smaller than a second gap between the annular member and the facing surface and a third gap between the at least one linking member and the facing surface. [2] The turbine according to claim 1, wherein the at least one stopper portion is configured integrally with the first plate-like member. [3] Turbine according to claim 2, where the first plate-like element contains: a tubular portion projecting from the rear surface of the first plate portion and inserted into a center hole of the annular member, and at least one claw portion projecting from the tubular portion to an outer peripheral side of an inner peripheral edge of the annular member, the inner peripheral edge of the annular member being interposed between the rear surface of the first plate portion and the claw portion, and the at least one stopper portion includes the at least one claw portion. [4] Turbine, comprising: a first housing having a screw flow path; a turbine wheel provided on an inner peripheral side of the screw flow path; a first plate-like member including an annular first plate portion; a second plate-like member including an annular second plate portion disposed to face the first plate portion and forming a gas flow path between the first plate portion and the second plate portion from the scroll flow path toward the turbine wheel; at least one variable nozzle vane arranged in the gas flow path; a second housing having a facing surface opposite to a rear surface of the first plate portion on a side opposite to a flow path wall surface facing the gas flow path, with a first space interposed therebetween; a biasing member disposed between the second housing and the first plate-like member and configured to bias the first plate portion toward one side of the gas flow path; at least one positioning pin, one end of which is inserted into a first hole formed on the rear surface of the first plate portion and the other end of which is inserted into a second hole formed on the facing surface of the second housing, in a state in which at least one of the one end and the other end has a gap; and an adhesive layer inserted in the gap, the adhesive strength of which decreases due to heat input during operation of the turbine. [5] A turbine according to claim 4, wherein the adhesive layer is formed of a thermoplastic resin material. [6] Turbine, comprising: a first housing having a screw flow path; a turbine wheel provided on an inner peripheral side of the screw flow path; a first plate-like member including an annular first plate portion; a second plate-like member including an annular second plate portion disposed to face the first plate portion and forming a gas flow path between the first plate portion and the second plate portion from the scroll flow path toward the turbine wheel; at least one variable nozzle vane arranged in the gas flow path; a second housing having a facing surface opposite to a rear surface of the first plate portion on a side opposite to a flow path wall surface facing the gas flow path, with a first space interposed therebetween; a biasing member disposed between the second housing and the first plate-like member and configured to bias the first plate portion toward one side of the gas flow path; at least one positioning pin, one end of which is inserted into a first hole formed on the rear surface of the first plate portion and the other end of which is inserted into a second hole formed on the facing surface of the second housing; and a sliding layer containing a solid lubricant covering at least one of an outer peripheral surface of one end of the at least one positioning pin, an outer peripheral surface of the other end of the at least one positioning pin, an inner peripheral surface of the first hole, and an inner peripheral surface of the second hole. [7] The turbine according to any one of claims 1 to 6, wherein at least one of the first hole and the second hole has a longitudinal direction along a radial direction of the turbine wheel. [8] Turbine according to one of claims 1 to 6, wherein the at least one positioning pin includes a plurality of positioning pins arranged at intervals along a circumferential direction of the turbine wheel, and in a cross section perpendicular to an axis line of the turbine wheel, a point at which distances from respective center positions of the plurality of positioning pins are equal is arranged to be shifted to a side of the tongue portion of the screw flow path with respect to the axis line of the turbine wheel. [9] Turbine according to one of claims 1 to 6, wherein the biasing element contains at least: a first preload plate portion extending along a radial direction of the turbine wheel and abutting against the second casing, and a second preload plate portion extending along the radial direction and abutting against the first plate-like member. [10] Turbocharger, comprising: the turbine according to any one of claims 1 to 6; and a centrifugal compressor configured to be driven by the turbine.

Images