Variable capacity turbocharger

1 . A turbocharger comprising:

a turbine blade wheel;

a rotating shaft to which the turbine blade wheel is fixed;

a first housing including a flow path through which gas received from an inlet flows;

a second housing rotatably supporting the rotating shaft;

a variable capacity assembly disposed in the first housing and configured to receive the gas from the flow path and to guide the gas to the turbine blade wheel;

an annular intermediate plate contacting the variable capacity assembly in an axial direction of the rotating shaft; and

a biasing member located between the intermediate plate and the second housing, the biasing member configured to apply a biasing force to the intermediate plate so as to press the intermediate plate against the variable capacity assembly,

wherein the first housing includes a housing contact surface that is in contact with the variable capacity assembly in the axial direction,

wherein the variable capacity assembly includes an assembly contact surface that is in contact with the housing contact surface in the axial direction,

wherein the intermediate plate includes:

a first contact surface in contact with the variable capacity assembly in the axial direction; and

a second contact surface that is located on a side opposite to the first contact surface in the axial direction, and in contact with the biasing member in the axial direction,

wherein each of the first contact surface and the second contact surface includes a high friction surface, and

wherein an entire surface of the first contact surface is the high friction surface.

2 . The turbocharger according to claim 1 , wherein the high friction surface is processed to include a knurled surface or a blasted surface.

3 . The turbocharger according to claim 1 ,

wherein the housing contact surface includes a high friction surface, and

wherein a surface roughness of the high friction surface of the housing contact surface is greater than a surface roughness of the assembly contact surface.

4 . The turbocharger according to claim 1 ,

wherein the variable capacity assembly includes:

an arrangement hole through which the turbine blade wheel or the rotating shaft is inserted; and

a second assembly contact surface surrounding the arrangement hole;

wherein the second contact surface of the intermediate plate is in contact with the second assembly contact surface, and

wherein the second assembly contact surface includes a second high friction surface.

5 . The turbocharger according to claim 1 ,

wherein the biasing member includes a biasing member contact surface in contact with the second contact surface of the intermediate plate, and

wherein the biasing member contact surface includes a second high friction surface.

6 . The turbocharger according to claim 1 ,

wherein the second housing includes a second housing contact surface in contact with the biasing member in the axial direction,

wherein the biasing member includes a biasing member contact surface in contact with the second housing contact surface, and

wherein at least one of the second housing contact surface and the biasing member contact surface includes a second high friction surface.

7 . The turbocharger according to claim 1 ,

wherein the variable capacity assembly includes an arrangement hole through which the turbine blade wheel or the rotating shaft is inserted,

wherein the second housing includes a second housing shoulder portion fitted into the arrangement hole,

wherein the arrangement hole includes an inner peripheral surface portion which faces the second housing shoulder portion,

wherein the second housing shoulder portion includes a shoulder outer surface in contact with the inner peripheral surface portion of the arrangement hole, and

wherein at least one of the inner peripheral surface portion of the arrangement hole and the shoulder outer surface includes a second high friction surface.

8 . A turbocharger comprising:

a turbine blade wheel;

a rotating shaft to which the turbine blade wheel is fixed;

a housing including:

a flow path through which gas received from an inlet flows; and

a connection flow path through which a gas passes from the flow path into the turbine blade wheel; and

a variable capacity assembly disposed in the housing and configured to receive the gas from the flow path and to guide the gas to the turbine blade wheel, the variable capacity assembly including:

a nozzle vane located in the connection flow path;

a nozzle ring rotatably supporting the nozzle vane; and

a drive ring rotating the nozzle vane and contacting the nozzle ring,

wherein the housing includes a housing contact surface in contact with the variable capacity assembly in an axial direction of the rotating shaft,

wherein the nozzle ring includes:

a nozzle ring contact surface in contact with the housing contact surface and located between the housing contact surface and the drive ring in the axial direction; and

an outer peripheral surface that faces an inner peripheral surface of the housing and that is separated from the inner peripheral surface of the housing in a radial direction of the rotating shaft,

wherein an entire surface of the nozzle ring contact surface has a high friction surface, and

wherein a surface roughness of the high friction surface is greater than a surface roughness of the outer peripheral surface of the nozzle ring.

9 . The turbocharger according to claim 8 ,

wherein the housing comprises a first housing which accommodates the turbine blade wheel and a second housing that is connected to the first housing and supports the rotating shaft,

wherein the nozzle ring is located between the first housing and the second housing,

wherein the turbocharger further comprises:

a heat shielding plate located between the first housing and the second housing and contacting the nozzle ring; and

a biasing member located between the heat shielding plate and the second housing, the biasing member configured to apply a biasing force to the heat shielding plate so as to press the heat shielding plate against the first housing via the nozzle ring, and

wherein the second housing comprises a bottom surface in contact with the biasing member, the bottom surface including a high friction surface.

10 . The turbocharger according to claim 8 ,

wherein the nozzle ring includes a sliding surface on which the nozzle vane is arranged and slides, and

wherein the surface roughness of the high friction surface is greater than a surface roughness of the sliding surface.

11 . The turbocharger according to claim 8 ,

wherein the housing comprises a first housing which accommodates the turbine blade wheel and a second housing that is connected to the first housing and supports the rotating shaft,

wherein the nozzle ring is located between the first housing and the second housing,

wherein the turbocharger further comprises:

a heat shielding plate located between the first housing and the second housing and contacting the nozzle ring; and

a biasing member located between the heat shielding plate and the second housing, the biasing member configured to apply a biasing force to the heat shielding plate so as to press the heat shielding plate against the first housing via the nozzle ring,

wherein the heat shielding plate includes:

a first contact surface in contact with the nozzle ring in the axial direction; and

a second contact surface which is located on a side opposite to the first contact surface in the axial direction, and is in contact with the biasing member in the axial direction, and

wherein each of the first contact surface and the second contact surface includes a high friction surface.

12 . A turbocharger comprising:

a turbine blade wheel;

a rotating shaft to which the turbine blade wheel is fixed;

a housing including a connection flow path through which gas passes, wherein the gas flows from the connection flow path into the turbine blade wheel;

a nozzle vane located in the connection flow path;

a nozzle ring rotatably supporting the nozzle vane;

a heat shielding plate located next to the nozzle ring in an axial direction of the rotating shaft; and

a biasing member configured to apply a biasing force to the heat shielding plate so as to press the heat shielding plate against the nozzle ring,

wherein the heat shielding plate includes:

a first contact surface contacting the nozzle ring in the axial direction; and

a second contact surface located on a side opposite to the first contact surface in the axial direction, and contacting the biasing member,

wherein each of the first contact surface and the second contact surface includes a high friction surface, and

wherein an entire surface of the first contact surface includes the high friction surface.

13 . The turbocharger according to claim 12 , wherein the high friction surface is processed to include a knurled surface or a blasted surface.

14 . The turbocharger according to claim 12 ,

wherein the nozzle ring includes a nozzle ring main surface which faces the connection flow path, and

wherein a surface roughness of the high friction surface is greater than a surface roughness of the nozzle ring main surface.

15 . A turbocharger comprising:

a turbine blade wheel;

a rotating shaft to which the turbine blade wheel is fixed;

a housing including a connection flow path through which gas passes, wherein the gas flows from the connection flow path into the turbine blade wheel;

a nozzle vane located in the connection flow path;

a nozzle ring rotatably supporting the nozzle vane;

a heat shielding plate located next to the nozzle ring in an axial direction of the rotating shaft; and

a biasing member configured to apply a biasing force to the heat shielding plate so as to press the heat shielding plate against the nozzle ring,

wherein the heat shielding plate has a ring-shape and comprises:

a first contact surface contacting the nozzle ring in the axial direction;

a second contact surface located on a side opposite to the first contact surface in the axial direction, and contacting the biasing member; and

an outer peripheral surface facing the housing,

wherein each of the first contact surface and the second contact surface includes a high friction surface, and

wherein the high friction surface has a ring shape along the outer peripheral surface of the heat shielding plate.

16 . The turbocharger according to claim 12 ,

wherein the housing comprises a turbine housing which accommodates the turbine blade wheel and a bearing housing that is connected to the turbine housing and supports the rotating shaft,

wherein the biasing member is located between the nozzle ring and the bearing housing, and

wherein the bearing housing comprises a bottom surface in contact with the biasing member, the bottom surface including a high friction surface.

17 . The turbocharger according to claim 12 , further comprising a drive ring configured to rotate the nozzle vane,

wherein the nozzle ring includes:

a nozzle ring main surface which faces the connection flow path;

an outer peripheral surface located around the nozzle ring main surface; and

an outer flange which protrudes from the outer peripheral surface in a radial direction of the rotating shaft, the outer flange including:

a first flange surface contacting the housing in the axial direction; and

a second flange surface located on a side opposite to the first flange surface in the axial direction and contacting the drive ring in the axial direction, and

wherein a surface roughness of the first flange surface is greater than a surface roughness of the second flange surface.

18 . The turbocharger according to claim 1 , wherein an entire surface of the second contact surface is the high friction surface.