Turbocharger Turbine Containment Structure

Patent metadata

Field	Value
Publication number	US-2016265382-A1
Application number	US-201514642033-A
Country	US
Kind code	A1
Filing date	Mar 9, 2015
Priority date	Mar 9, 2015
Publication date	Sep 15, 2016
Grant date	—

Abstract

A turbocharger is provided that includes a turbine housing including a gas inlet passage. A turbine wheel has a plurality of blades and is arranged in the turbine housing. A bearing housing is connected to the turbine housing. A shaft is rotatably supported in the bearing housing and connected to the turbine wheel. A shroud is arranged in surrounding relation to at least a portion of the turbine wheel, the shroud being arranged in spaced relation from and not in contact with the turbine housing. A fastening system secures the shroud relative to the bearing housing. The fastening system is configured to fracture when a force is exerted on the shroud corresponding to at least a portion of the turbine wheel contacting the shroud.

First claim

We claim:

1 . A turbocharger comprising:
a turbine housing including a gas inlet passage; a turbine wheel that has a plurality of blades and is arranged in the turbine housing; a bearing housing connected to the turbine housing; a shaft rotatably supported in the bearing housing and connected to the turbine wheel; a shroud arranged in surrounding relation to at least a portion of the turbine wheel, the shroud being arranged in spaced relation from and not in contact with the turbine housing; and a fastening system securing the shroud relative to the bearing housing, the fastening system being configured to fracture when a force is exerted on the shroud corresponding to at least a portion of the turbine wheel contacting the shroud.

2 . The turbocharger of claim 1 further including a heat shield that is secured to the bearing housing and wherein the fastening system secures the shroud to the heat shield.

3 . The turbocharger of claim 2 wherein the fastening system comprises a plurality of shear bolts.

4 . The turbocharger of claim 3 further including a nozzle ring interposed between the shroud and the heat shield, the nozzle ring being disposed around the turbine wheel and including a plurality of vanes with flow channels being defined between the vanes that are in fluid communication the gas inlet passage and with the turbine wheel.

5 . The turbocharger of claim 4 wherein the nozzle ring is integrally formed with the nozzle ring.

6 . The turbocharger of claim 5 wherein the flow channels defined by the vanes are configured to direct gas tangentially and radially inward toward an inner diameter of the turbine wheel and the shroud is configured to define a flow path in communication with the gas inlet passage and the flow channels and that extends in a direction substantially parallel to a rotational axis of the turbine wheel.

7 . The turbocharger of claim 1 wherein the shroud is configured to be rotatable relative to turbine housing when the fastening system fractures.

8 . The turbocharger of claim 3 wherein each shear bolt has an associated spring washer.

9 . The turbocharger of claim 3 wherein each shear bolt is trapped at a first end between the shroud and the turbine housing and at a second end between the heat shield and the bearing housing.

10 . A method for dissipating energy resulting from failure of a rotating turbine wheel in a turbocharger, the turbine wheel being arranged in a turbine housing and being connected to a shaft that is rotatably supported in a bearing housing, the method comprising:
arranging a shroud in surrounding relation to at least a portion of the turbine wheel, the shroud being arranged in spaced relation from and not in contact with the turbine housing; and securing the shroud relative to the bearing housing with a fastening system configured to fracture when a force is exerted on the shroud corresponding to at least a portion of the turbine wheel contacts the shroud, wherein the shroud is configured to rotate relative to turbine housing when the fastening system fractures.

11 . The method of claim 10 wherein the fastening system secures the shroud to a heat shield that is secured to the bearing housing.

12 . The method of claim 11 wherein the fastening system comprises a plurality of shear bolts.

13 . The method of claim 12 further including providing a nozzle ring interposed between the shroud and the heat shield, the nozzle ring being disposed around the turbine wheel and including a plurality of vanes with flow channels being defined between the vanes that are in fluid communication the gas inlet passage and with the turbine wheel.

14 . The method of claim 13 wherein the nozzle ring is integrally formed with the nozzle ring.

15 . The method of claim 13 wherein the flow channels defined by the vanes are configured to direct gas tangentially and radially inward toward an inner diameter of the turbine wheel and the shroud is configured to define a flow path in communication with the gas inlet passage and the flow channels and that extends in a direction substantially parallel to a rotational axis of the turbine wheel.

16 . An internal combustion engine having a plurality of combustion chambers formed in a cylinder block, an intake manifold disposed to provide air or a mixture of air with exhaust gas to the combustion chambers, and an exhaust manifold disposed to receive exhaust gas from the combustion chambers, the engine further comprising:
a turbine housing including a gas inlet passage; a turbine wheel that has a plurality of blades and is arranged in the turbine housing; a bearing housing connected to the turbine housing; a shaft rotatably supported in the bearing housing and connected to the turbine wheel; a shroud arranged in surrounding relation to at least a portion of the turbine wheel, the shroud being arranged in spaced relation from and not in contact with the turbine housing; and a fastening system securing the shroud relative to the bearing housing, the fastening system being configured to fracture when a force is exerted on the shroud corresponding to at least a portion of the turbine wheel contacting the shroud.

17 . The engine of claim 16 further including a heat shield that is secured to the bearing housing and wherein the fastening system secures the shroud to the heat shield.

18 . The engine of claim 17 wherein the fastening system comprises a plurality of shear bolts.

19 . The engine of claim 18 further including a nozzle ring interposed between the shroud and the heat shield, the nozzle ring being disposed around the turbine wheel and including a plurality of vanes with flow channels being defined between the vanes that are in fluid communication the gas inlet passage and with the turbine wheel.

20 . The engine of claim 19 wherein the flow channels defined by the vanes are configured to direct gas tangentially and radially inward toward an inner diameter of the turbine wheel and the shroud is configured to define a flow path in communication with the gas inlet passage and the flow channels and that extends in a direction substantially parallel to a rotational axis of the turbine wheel.

Assignees

• Caterpillar Inc

Inventors

• Annati Richard E
• Powers Gary W
• Mccormack Jeffrey W
• Frick Matthew J

Classifications

• F02M35/104

  Intake manifolds · CPC title

• F02B37/00 Primary

  Engines characterised by provision of pumps driven at least for part of the time by exhaust · CPC title

• F05D2240/11

  Shroud seal segments · CPC title

• F01D21/04 Primary

  responsive to undesired position of rotor relative to stator {or to breaking-off of a part of the rotor}, e.g. indicating such position · CPC title

• F05D2240/15

  Heat shield · CPC title