A turbocharger includes: a nozzle drive mechanism for driving a plurality of nozzle vanes; and a support ring for holding the nozzle drive mechanism, the support ring having a main body portion having a heat shielding portion facing a turbine impeller in a direction of a rotational axis of the turbine impeller.

BACKGROUND ART

Technical Field

The present disclosure relates to a turbocharger including a nozzle drive mechanism for driving a plurality of nozzle vanes.

Related Art

Conventionally, turbochargers of a variable-capacity type are widely used. In such a turbocharger, for example as illustrated in Patent Literature 1, a plurality of nozzle vanes are arranged while annularly aligned in a flow passage for guiding exhaust gas from a turbine scroll flow passage to a turbine impeller. The nozzle vanes are attached to a bladed shaft. When the bladed shaft rotates by the power of an actuator, the angle of the nozzle vanes change in the flow passage as the bladed shaft rotates. The flow passage width (so-called nozzle throat width) changes, and thereby the flow rate of exhaust gas flowing through the flow passage is controlled.

In addition, in Patent Literature 1, a heat shielding plate is provided between a turbine housing and a bearing housing. The turbine housing accommodates the turbine impeller. The bearing housing accommodates a bearing. The heat shielding plate suppresses heat transfer from the turbine impeller side to the bearing side.

CITATION LIST

Patent Literature

SUMMARY

Technical Problem

In the turbocharger of the variable-capacity type described above, the number of parts for changing the angle of the nozzle vanes is large. Therefore, assembling work is complicated. In a case where a heat shielding plate is provided to the bearing housing, the number of parts and assembling work further increase. Providing a heat shielding plate in the bearing housing results in as a factor that deteriorates the workability of assembly.

Therefore, an object of the present disclosure is to provide a turbocharger capable of improving workability of assembly.

Solution to Problem

In order to solve the above problem, a turbocharger according to one aspect of the present disclosure includes: a nozzle drive mechanism for driving a plurality of nozzle vanes; and a support ring for holding the nozzle drive mechanism, the support ring having a heat shielding portion facing a turbine impeller in a direction of a rotational axis of the turbine impeller.

The support ring may protrude outward in a radial direction of the support ring and may have a clamped portion that is clamped between a turbine housing and a bearing housing.

In order to solve the above problem, another turbocharger according to one aspect of the present disclosure includes: a nozzle drive mechanism for driving a plurality of nozzle vanes; a support ring having a main body portion for holding the nozzle drive mechanism and a clamped portion protruding radially outward from the main body portion and clamed between a turbine housing and a bearing housing; and a heat shielding plate, an inner diameter end portion of which facing a rear surface of a turbine impeller and an outer diameter end portion of which extending to a position facing the clamped portion, the heat shielding plate clamped between the turbine housing and the bearing housing.

Effects of Disclosure

According to the present disclosure, workability of assembly can be improved.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. Dimensions, materials, other specific numerical values, and the like illustrated in embodiments are merely examples for facilitating understanding, and the present disclosure is not limited thereby except for a case where it is specifically mentioned. Note that, in the present specification and the drawings, components having substantially the same function and structure are denoted by the same symbol, and redundant explanations are omitted. Components not directly related to the present disclosure are not illustrated.

FIG. 1is a schematic cross-sectional view of a turbocharger C. Hereinafter, descriptions are given assuming that a direction of an arrow L illustrated inFIG. 1is the left side of the turbocharger C. Descriptions are given assuming that a direction of an arrow R illustrated inFIG. 1is the right side of the turbocharger C. As illustrated inFIG. 1, the turbocharger C includes a turbocharger main body1. The turbocharger main body1includes a bearing housing2. A turbine housing4is connected to the left side of the bearing housing2by a fastening bolt3. A compressor housing6is connected to the right side of the bearing housing2by a fastening bolt5. The bearing housing2, the turbine housing4, and the compressor housing6are integrated.

A receiving hole2ais formed in the bearing housing2. The receiving hole2apenetrates through the turbocharger C in the left-right direction. A shaft8is pivotally supported in a freely rotatable manner by a radial bearing7(a semi-floating bearing is illustrated inFIG. 1as an example in this embodiment) accommodated in the receiving hole2a. At a left end portion of the shaft8, a turbine impeller9is provided. The turbine impeller9is accommodated in the turbine housing4in a freely rotatable manner. Furthermore, a compressor impeller10is provided at a right end portion of the shaft8. The compressor impeller10is accommodated in the compressor housing6in a freely rotatable manner.

An intake port11is formed in the compressor housing6. The intake port11opens to the right side of the turbocharger C. The intake port11is connected to an air cleaner (not illustrated). Furthermore, in the state where the bearing housing2and the compressor housing6are connected by the fastening bolt5, a diffuser flow passage12is formed. The diffuser flow passage12is formed by opposing surfaces of the bearing housing2and the compressor housing6. The diffuser flow passage12pressurizes the air. The diffuser flow passage12is annularly formed outward from an inner side in a radial direction of the shaft8. The diffuser flow passage12communicates with the intake port11via the compressor impeller10on an inner side in the radial direction of the shaft8.

Furthermore, the compressor housing6includes a compressor scroll flow passage13. The compressor scroll flow passage13is annular. The compressor scroll flow passage13is positioned on an outer side in the radial direction of the shaft8with respect to the diffuser flow passage12. The compressor scroll flow passage13communicates with an intake port of an engine (not illustrated). The compressor scroll flow passage13also communicates with the diffuser flow passage12. When the compressor impeller10rotates, therefore, the air is sucked into the compressor housing6from the intake port11. The sucked air is accelerated and pressurized in the process of flowing through blades of the compressor impeller10. The accelerated and pressurized air is further pressurized (recovered of the pressure) by the diffuser flow passage12and the compressor scroll flow passage13. The pressurized air is guided to the engine.

In the state where the bearing housing2and the turbine housing4are connected by the fastening bolt3, a clearance14is formed between opposing surfaces of the bearing housing2and the turbine housing4. The clearance14is a portion in which a flow passage x, in which nozzle vanes62that will be described later are arranged and through which exhaust gas flows, is formed. The flow passage x is annularly formed outward from an inner side in the radial direction of the shaft8(turbine impeller9).

An exhaust port16is formed in the turbine housing4. The exhaust port16communicates with a turbine scroll flow passage15via the turbine impeller9. The exhaust port16faces a front surface of the turbine impeller9. The exhaust port16is connected to an exhaust gas purification device (not illustrated).

The turbine scroll flow passage15communicates with a gas inlet port (not illustrated). Exhaust gas discharged from the engine is guided to the gas inlet port. The turbine scroll flow passage15communicates also with the flow passage x. Therefore, exhaust gas guided from the gas inlet port to the turbine scroll flow passage15is guided to the exhaust port16via the flow passage x and the turbine impeller9. That is, the flow passage x extends from the turbine scroll flow passage15toward the turbine impeller9. The exhaust gas rotates the turbine impeller9in the process of flowing therethrough. The turning force of the turbine impeller9is further transmitted to the compressor impeller10via the shaft8. The turning force of the compressor impeller10causes the air to be pressurized and guided to the intake port of the engine.

At this time, when a flow rate of the exhaust gas guided to the turbine housing4changes, the rotation amounts of the turbine impeller9and the compressor impeller10change. Depending on an operation status of the engine, there may be a case where the air pressurized to a desired pressure cannot be sufficiently guided to the intake port of the engine. Therefore, the turbocharger C includes a nozzle drive mechanism20.

The nozzle drive mechanism20changes the width (nozzle throat width which will be described later) of the flow passage x of the turbine housing4. The nozzle drive mechanism20changes the flow velocity of exhaust gas guided to the turbine impeller9depending on the flow rate of the exhaust gas. Specifically, in a case where the rotational speed of the engine is low and the flow rate of exhaust gas is small, the nozzle drive mechanism20reduces the degree of opening of the flow passage x to increase the flow velocity of exhaust gas guided to the turbine impeller9. In this manner, the nozzle drive mechanism20can cause the turbine impeller9to rotate even with a small flow rate. A configuration of the nozzle drive mechanism20will be described below.

The nozzle drive mechanism20includes a shroud ring21and a nozzle ring22. The shroud ring21is provided on the turbine housing4side. The nozzle ring22is provided on the bearing housing2side while facing the shroud ring21. The flow passage x is partitioned by the shroud ring21and the nozzle ring22.

The shroud ring21has a main body portion21a. The main body portion21ahas a thin plate ring shape. The nozzle ring22has a main body portion22a. For example, the main body portion22ahas a thin plate ring shape. The main body portion22ahas a diameter equivalent to that of the main body portion21aof the shroud ring21. The nozzle ring22is arranged opposed to the shroud ring21with a predetermined space therebetween.

FIG. 2Ais an extracted diagram of a broken line part in an upper part ofFIG. 1.FIG. 2Bis an extracted diagram of a one-dot chain line part in a lower part ofFIG. 1. As illustrated inFIG. 2B, a pin shaft hole23ais provided on a surface of the main body portion21aof the shroud ring21that faces the nozzle ring22. A plurality of pin shaft holes23ais formed at equal intervals in the circumferential direction (three in the present embodiment, but only one is illustrated inFIG. 2B).

Moreover, a pin shaft through hole25ais formed in the main body portion22aof the nozzle ring22. The pin shaft through hole25apenetrates through the main body portion22ain the thickness direction (axial direction of the shaft8). Multiple pin shaft through holes25aare formed at equal intervals in the circumferential direction (three in the present embodiment, only one is illustrated inFIG. 2B). The pin shaft holes23aformed in the shroud ring21face the pin shaft through holes25aformed in the nozzle ring22. A connecting pin24is inserted through a pin shaft hole23aand a pin shaft through hole25a.

Specifically, as illustrated inFIG. 2B, one end of a connecting pin24is inserted through a pin shaft through hole25aof the nozzle ring22. The other end of the connecting pin24is inserted into a pin shaft hole23aof the shroud ring21. Multiple connecting pins24(three in this embodiment, only one is illustrated inFIG. 2B) are arranged while spaced apart at equal intervals in the circumferential direction. The connecting pins24keep the facing interval from the shroud ring21constant.

Furthermore, one end of a connecting pin24inserted through the pin shaft through hole25aof the nozzle ring22protrudes to the right side of the nozzle ring22. The protruding portion of the connecting pin24is caulked. In this manner, a support ring30and a guide ring40are attached to the right side of the nozzle ring22. The support ring30has a main body portion31. The main body portion31has a bottomed cylindrical shape. The support ring30has a cross-sectional shape in which a member having a thin plate shape is bent (seeFIG. 1).

FIG. 3is a plan view of the support ring30and the guide ring40. InFIG. 3, the front side of the drawing faces the right side ofFIGS. 2A and 2B. InFIG. 3, the rear side of the drawing faces the left side ofFIGS. 2A and 2B. As illustrated inFIGS. 2A and 2B, the support ring30includes the main body portion31and a flange portion32(clamped portion). The flange portion32is annular. The flange portion32is bent radially outward from the right end portion (end portion on the front side inFIG. 3) of the main body portion31. Meanwhile, the main body portion31includes a bottom surface portion33(indicated by cross hatching inFIG. 3) and a cylindrical portion34. The bottom surface portion33extends in the radial direction. The cylindrical portion34is bent from the outer circumferential edge of the bottom surface portion33toward the flange portion32. That is, the bottom surface portion33is bent inward in the radial direction from the left end portion (end portion on the rear side inFIG. 3) of the cylindrical portion34.

Moreover, the flange portion32is clamped between the bearing housing2and the turbine housing4as illustrated inFIGS. 2A and 2B. In the above state, the fastening bolt3fastens the bearing housing2and the turbine housing4, thereby holding the support ring30in the turbine housing4. By holding the support ring30in the turbine housing4, whole of the nozzle drive mechanism20is held inside the turbine housing4.

The guide ring40has a main body portion41which is annular. An inner diameter of the main body portion41of the guide ring40is roughly equal to an inner diameter of the bottom surface portion33of the support ring30. The main body portion41is arranged on a radially inner side of the cylindrical portion34while being in contact with the bottom surface portion33. InFIG. 3, a part of the bottom surface portion33of the support ring30is hidden by the guide ring40.

As illustrated inFIG. 3, ring holes33aare provided in the bottom surface portion33of the support ring30. One end of a connecting pin24described above can be inserted through a ring hole33a. Three ring holes33aare provided at equal intervals in the circumferential direction. In addition, three guide holes41aare provided in the main body portion41of the guide ring40. The guide holes41aface the ring holes33a. One end of a connecting pin24is inserted through a guide hole41a. A connecting pin24is inserted through a ring hole33aand a guide hole41aand caulked. In this manner, the support ring30, the shroud ring21, the nozzle ring22, and the guide ring40are connected. That is, the shroud ring21and the nozzle ring22are held in the turbine housing4via the support ring30.

In addition, through holes33bare provided on the bottom surface portion33on an inner diameter side of the ring holes33a. The plurality of (eleven in the present embodiment) through holes33bis provided in the circumferential direction of the support ring30. One end of a bladed shaft62ais inserted through a through hole33bas will be described later.

Furthermore, the main body portion41of the guide ring40is provided with support pieces42as illustrated inFIG. 3. The plurality of support pieces42(ten in this embodiment) are provided while spaced apart from each other in the circumferential direction. As illustrated inFIGS. 2A and 2B, a support piece42includes a support portion42aand a fall preventing portion42b. The support portion42ais bent from the main body portion41to the right side (front side inFIG. 3). The fall preventing portion42bis bent outward in the radial direction from the support portion42a. The fall preventing portion42bfaces the main body portion41while spaced apart therefrom. A drive ring50is freely rotatably supported by the support pieces42(seeFIG. 4).

FIG. 4is a view illustrating the drive ring50supported by the guide ring40. InFIG. 4, the bottom surface portion33of the support ring30is indicated by cross-hatching to facilitate understanding. InFIG. 4, the drive ring50is indicated in cross-hatching that is finer than that of the bottom surface portion33.

The drive ring50is formed by an annular thin plate member. The support portions42aof the support pieces42are positioned on a radially inner side of the drive ring50. The drive ring50is freely rotatably supported between the fall preventing portions42band the bottom surface portion33. As illustrated inFIGS. 2A and 4, a plurality of engagement recessed portions51is formed in the drive ring50in the circumferential direction. An engagement recessed portion51is cut out radially outward from an end portion on the inner peripheral side of the drive ring50. One end of a transmission link60is engaged with an engagement recessed portion51.

As illustrated inFIGS. 2B and 4, a second engagement recessed portion52is further formed at the end portion on the inner peripheral side of the drive ring50. The second engagement recessed portion52has a similar shape to that of an engagement recessed portion51. One end of a link plate61is engaged with the second engagement recessed portion52. The link plate61has a similar shape to that of a transmission link60.

Note that a fitting hole60ais formed on the other end side of a transmission link60. A link hole61ais formed on the other end side of the link plate61. As illustrated inFIG. 2A, a bladed shaft62ais attached in the fitting hole60awhile inserted therethrough. The bladed shaft62ais attached to a nozzle vane62. As illustrated inFIG. 2B, a drive shaft63is fitted in the link hole61aof the link plate61.

The bladed shaft62ais inserted through a bladed shaft hole23band a bladed shaft through hole25b. The bladed shaft62ais pivotally supported by the bladed shaft hole23band the bladed shaft through hole25bin a freely rotatable manner. The bladed shaft hole23bis provided on a radially inner side of the pin shaft hole23ain the main body portion21aof the shroud ring21. The bladed shaft hole23bis provided on a surface of the main body portion21athat faces the nozzle ring22. A plurality of bladed shaft holes23b(eleven in the present embodiment, but only one is illustrated inFIG. 2A) is formed in the circumferential direction of the main body portion21a. The bladed shaft holes23bare arranged at equal intervals in the circumferential direction of the main body portion21a.

Similarly, the bladed shaft through hole25bis provided on a radially inner side of the pin shaft through hole25ain the main body portion22aof the nozzle ring22. The bladed shaft through hole25bpenetrates through the main body portion22ain the thickness direction (axial direction of the shaft8). A plurality of bladed shaft through holes25b(eleven in the present embodiment, but only one is illustrated inFIG. 2A) is formed in the circumferential direction of the main body portion22a. The bladed shaft through holes25bare arranged at equal intervals in the circumferential direction of the main body portion22a. The bladed shaft holes23bformed in the shroud ring21and the bladed shaft through holes25bformed in the nozzle ring22are arranged while facing each other.

Furthermore, one end of the bladed shaft62ainserted through the bladed shaft through hole25bof the nozzle ring22protrudes to the right side of the nozzle ring22. The other end of the bladed shaft62ais inserted through the fitting hole60aof the transmission link60. The protruding portion of the bladed shaft62ais caulked. The transmission link60is attached to the bladed shaft62a.

In this manner, a plurality of bladed shafts62aand a plurality of nozzle vanes62are annularly arranged in the flow passage x while spaced apart from each other in the rotation direction of the turbine impeller9. The drive shaft63extends to the right side of the drive ring50as illustrated inFIG. 2B. The extended portion of the drive shaft63is inserted through a bearing64. To describe in detail, the bearing64has a main body portion64awhich is annular. An inner circumferential surface of a bearing hole64bof the main body portion64aserves as a bearing surface. The drive shaft63is inserted through the bearing hole64b.

An end of the drive shaft63is connected with a drive lever65. The turbocharger C is provided with an actuator66outside the housing (seeFIG. 1). The drive lever65is connected to the actuator66. When the actuator66drives the drive lever65, as illustrated inFIG. 2B, the drive lever65and the drive shaft63swing (rotate) about the axial center of the drive shaft63. The turning force from the actuator66is transmitted to the link plate61. In this manner, the link plate61swings.

Then, the second engagement recessed portion52is pressed against the link plate61illustrated inFIG. 4. The drive ring50rotates. By the rotation of the drive ring50, the transmission links60separately engaged with multiple of the engagement recessed portions51are pressed and swing. As the transmission links60swing, the plurality of bladed shafts62arotates. As the bladed shafts62arotate, the angle of the plurality of nozzle vanes62is changed within the flow passage x. In this manner, the nozzle drive mechanism20is swung by the link plate61by the power of the actuator66. In this manner, the nozzle drive mechanism20drives the plurality of nozzle vanes62. The nozzle drive mechanism20changes the angle of the plurality of nozzle vanes62. The nozzle drive mechanism20allows the area of the flow passage x (the flow passage width between adjacent nozzle vanes62(so-called nozzle throat width)) to be variable.

Meanwhile, a center hole33dis provided at the center of the bottom surface portion33of the support ring30as illustrated inFIG. 2A. The center hole33dpenetrates through the bottom surface portion33in the axial direction of the shaft8.

As illustrated inFIGS. 2A and 2B, an opposing surface2bis a portion of the bearing housing2that faces the bottom surface portion33of the support ring30. On the opposing surface2b, an annular protrusion2cis provided. The annular protrusion2cprotrudes toward the turbine impeller9side. The shaft8(seeFIG. 1) is inserted through an inner peripheral side of the annular protrusion2c. The annular protrusion2cis inserted through the center hole33dof the bottom surface portion33.

The bottom surface portion33is formed with a heat shielding portion33e. The heat shielding portion33eis continuous radially outward from the center hole33dof the bottom surface portion33. The heat shielding portion33eprotrudes in the axial direction of the shaft8from a left side surface (turbine impeller9side) of the bottom surface portion33inFIGS. 2A and 2B. The heat shielding portion33eis formed to be thicker than an outer portion in the radial direction of the heat shielding portion33eby an amount protruding in the axial direction of the shaft8. The protruding portion of the heat shielding portion33eis a stepped portion. The stepped portion has a side surface facing radially outward. The stepped portion is inserted through the inner peripheral side of the nozzle ring22. The side surface of the stepped portion faces the inner circumferential surface of the nozzle ring22.

The heat shielding portion33eextends to a position facing the turbine impeller9in the direction of the rotational axis of the turbine impeller9(axial direction of the shaft8). The heat shielding portion33eshields the heat from the turbine impeller9to the radial bearing7side.

By including the heat shielding portion33ein the support ring30in this manner, the number of parts can be reduced as compared with a case where a heat shielding plate is separately provided in addition to the support ring30. This enables improvement in the workability of assembly.

Furthermore, as described above, the flange portion32is clamped between the bearing housing2and the turbine housing4. That is, the flange portion32functions as a clamped portion. The clamped portion is clamped between the bearing housing2and the turbine housing4.

Therefore, it is possible to assemble the support ring30that functions also as a heat shielding portion by a simple operation of clamping the flange portion32between the bearing housing2and the turbine housing4. This enables further improvement in the workability.

FIGS. 5 and 6are explanatory diagrams for explaining a first modification. InFIG. 5, a cross-sectional view of a position of the first modification corresponding toFIG. 2Ais illustrated. InFIG. 5, a cross-sectional view of a position of the first modification corresponding toFIG. 2Bis illustrated. In the embodiment described above, the annular protrusion2cis inserted through the center hole33dof the bottom surface portion33of the support ring30.

In the first modification, as illustrated inFIGS. 5 and 6, an annular groove2eis formed on an outer circumferential surface2dof an annular protrusion2c. A tip portion2fis a portion of the annular protrusion2con a tip side (left side inFIGS. 5 and 6) with respect to the annular groove2e. A base portion2gis a portion of the annular protrusion2con the base side (right side inFIGS. 5 and 6) with respect to the annular groove2e. The tip portion2fhas a smaller diameter than that of the base portion2g. A stepped surface2his formed between the annular groove2eand the base portion2g. The stepped surface2hextends in a radial direction of a shaft8.

Meanwhile, a center hole33dof a support ring30has a small diameter portion33fand a large diameter portion33g. The small diameter portion33fis formed on a turbine impeller9side (left side inFIGS. 5 and 6) of the center hole33d. The large diameter portion33gis formed on an opposing surface2bside (right side inFIGS. 5 and 6) of a bearing housing2in the center hole33d. The small diameter portion33fhas a smaller diameter than that of the large diameter portion33g. Between the small diameter portion33fand the large diameter portion33g, a stepped surface33his formed. The stepped surface33hextends in the radial direction of the shaft8.

Moreover, the annular groove2eis fitted with a sealing ring70. An outer diameter of the sealing ring70is slightly larger than an inner diameter of the large diameter portion33gof the support ring30when the sealing ring70is in the natural length (before assembly). The sealing ring70is press-fitted into the large diameter portion33g. Furthermore, the sealing ring70is provided between the stepped surface2hof the bearing housing2and the stepped surface33hof the support ring30.

By the elastic force of the sealing ring70, an outer circumferential surface of the sealing ring70is pressed radially against the large diameter portion33g. In addition, by the gas pressure during operation, a side surface of the sealing ring70is pressed against one of the two stepped surfaces2hand33h, thereby enhancing the sealing performance.

Exhaust gas flowed into a turbine scroll flow passage15slightly leaks out from a clearance S upstream of a flow passage x toward the support ring30side. The leaked exhaust gas may flow through a space formed between the support ring30and the bearing housing2on the right side inFIGS. 5 and 6rather than the support ring30in some cases. The exhaust gas flowed in may flow out to a rear side of the turbine impeller9in some cases. By providing the sealing ring70, such flow of exhaust gas is suppressed. This enables suppressing deterioration of the turbine efficiency.

FIG. 7is an explanatory diagram for explaining a second modification. InFIG. 7, a cross-sectional view of a position of the second modification corresponding toFIG. 2Ais illustrated. In the embodiment and the first modification described above, the case where the heat shielding portion33eis formed in the support ring30has been described. In the second modification, a heat shielding plate180which is a separate body from the support ring130is provided.

To describe in detail, a bottom surface portion133of a main body portion131of a support ring130is bent from a cylindrical portion134. The bottom surface portion133extends radially inward from a bladed shaft62a. An outer diameter end portion180aof the heat shielding plate180extends radially outward to a position facing a flange portion132(clamped portion). The outer diameter end portion180ahas the same outer diameter as the outer diameter of the flange portion132of the support ring130, for example. An annular protrusion2cof a bearing housing2is inserted through a center hole180bof the heat shielding plate180.

Furthermore, the heat shielding plate180extends to a position corresponding to the heat shielding portion33eof the support ring30in the embodiment described above. That is, the heat shielding portion180cis formed in the heat shielding plate180. Like the heat shielding portion33e, the heat shielding portion180cis inserted into an inner circumferential side of the nozzle ring22. A sealing ring70is arranged on an outer periphery of the heat shielding portion180c.

In this manner, the heat shielding portion180cof the heat shielding plate180(inner diameter end portion180dof the heat shielding plate180) extends to a position facing the turbine impeller9in the rotational axis direction of the turbine impeller9(axial direction of the shaft8). The heat shielding portion180cshields the heat from the turbine impeller9to a radial bearing7side.

The flange portion132of the support ring130and the outer diameter end portion180aof the heat shielding plate180are clamped between the turbine housing4and the bearing housing2. The flange portion132and the heat shielding plate180are clamped between an outer diameter end portion2iof the bearing housing2and an opposing portion4aof the turbine housing4in a stacked state. The opposing portion4afaces the outer diameter end portion2iin the axial direction of the shaft8. Here, the flange portion132and the heat shielding plate180may be clamped between the outer diameter end portion2iof the bearing housing2and the opposing portion4aof the turbine housing4, with a separate member interposed therebetween.

Only by fastening the bearing housing2and the turbine housing4by the fastening bolt3, the support ring130and the heat shielding plate180can be simultaneously held inside the bearing housing2and the turbine housing4. This enables improvement in the workability.

Although the embodiment has been described with reference to the accompanying drawings, it is naturally understood that the present disclosure is not limited to the above embodiments. It is clear that those skilled in the art can conceive various modifications or variations within the scope described in the claims, and it is understood that they are naturally also within the technical scope of the present disclosure.

INDUSTRIAL APPLICABILITY

The present disclosure can be applied to a turbocharger including a nozzle drive mechanism for driving a plurality of nozzle vanes.