Die-cast diffuser for a turbocharger

Patent metadata

Field	Value
Publication number	US-9482239-B2
Application number	US-201013511351-A
Country	US
Kind code	B2
Filing date	Dec 3, 2010
Priority date	Dec 17, 2009
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

A compressor housing of an exhaust-gas turbocharger is formed as a pressure-die-cast housing to achieve cost reduction in relation to permanent-mold-cast housings. Since it is not possible in a pressure-die-cast housing to realize round transitions of the spiral in the direction of the housing rear side because this would prevent removal from a mold, the bearing-housing-side diffuser wall is formed as a separate component.

First claim

The invention claimed is:

1. An exhaust-gas turbocharger ( 1 ) having
a turbine ( 2 ), and
a compressor ( 3 ) which has a metal compressor housing ( 10 ) having an inlet, said compressor housing ( 10 ) being fastened to a bearing housing ( 4 ) and having a compressor spiral ( 13 ) having an inner wall ( 15 ) on the compressor inlet side and a diffuser wall ( 14 ) on the bearing housing side,

wherein
the compressor housing ( 10 ) is formed as a pressure-die-cast housing,
the bearing-housing-side diffuser wall ( 14 ) is formed as a separate component connected to the compressor housing ( 10 ) and which has an internal rounding ( 16 ) in a transition region transitioning to the inner wall ( 15 ) of the compressor housing spiral ( 13 ),
the bearing-housing-side diffuser wall ( 14 ) is a plastic injection-molded part, and
the plastic injection-molded part has a side facing the bearing housing, wherein the side facing the bearing housing is completely backed by a metal wall ( 18 , 18 a ) which is a structural component of the compressor housing or a structural component of the bearing housing.

2. The exhaust-gas turbocharger as claimed in claim 1 , wherein the bearing-housing-side diffuser wall ( 14 ) is connected to the compressor housing ( 10 ) by means of positively locking connecting devices.

3. The exhaust-gas turbocharger as claimed in claim 2 , wherein the bearing-housing-side diffuser wall ( 14 ) is clamped with the compressor housing ( 10 ) by means of a compressor housing rear wall ( 18 ).

4. The exhaust-gas turbocharger as claimed in claim 2 , wherein the bearing-housing-side diffuser wall ( 14 ) is clamped with the compressor housing ( 10 ) by means of a bearing housing flange ( 18 a ).

5. The exhaust-gas turbocharger as claimed in claim 1 , wherein the plastic bearing-housing-side diffuser wall ( 14 ), viewed in axial section, comprises
an inner wall region ( 17 ), which runs straight, and
a rounding ( 16 ) for transitioning flow to an adjoining inner wall ( 15 ) of the compressor spiral ( 13 ) of the compressor housing ( 10 ).

6. The exhaust-gas turbocharger as claimed in claim 1 , wherein the plastic bearing-housing-side diffuser wall ( 14 ), viewed in axial section, comprises
an inner wall region ( 17 ), which runs straight, and
a rounding ( 16 ) which runs from the straight inner wall region ( 17 ) to a straight region perpendicular to the straight inner wall region ( 17 ) adjoining an inner wall ( 15 ) of the compressor spiral ( 13 ) of the compressor housing ( 10 ).

7. An exhaust-gas turbocharger ( 1 )
having a turbine ( 2 ), and
having a compressor ( 3 ) which has a metal compressor housing ( 10 ), said compressor housing ( 10 ) being fastened to a bearing housing ( 4 ) and having a compressor spiral ( 13 ) having an inner wall ( 15 ) and a bearing-housing-side diffuser wall ( 14 ),

wherein
the compressor housing ( 10 ) is formed as a pressure-die-cast housing,
the bearing-housing-side diffuser wall ( 14 ) is formed as a separate plastic component which can be connected to the compressor housing ( 10 ) and which has an internal rounding ( 16 ) in a transition region to the inner wall ( 15 ) of the compressor housing spiral ( 13 ),
the bearing-housing-side diffuser wall ( 14 ) is a plastic injection-molded part,
the plastic injection-molded part has a side facing the bearing housing, wherein the side facing the bearing housing is completely backed by a metal wall ( 18 , 18 a ) which is a structural component of the compressor housing or a structural component of the bearing housing,
and
the bearing-housing-side diffuser wall ( 14 ) is adhesively bonded at least one of axially and radially to the compressor housing ( 10 ).

8. The exhaust-gas turbocharger as claimed in claim 7 , wherein the plastic bearing-housing-side diffuser wall ( 14 ), viewed in axial section, comprises
an inner wall region ( 17 ), which runs straight, and
a rounding ( 16 ) for transitioning flow to an adjoining inner wall ( 15 ) of the compressor spiral ( 13 ) of the compressor housing ( 10 ).

9. The exhaust-gas turbocharger as claimed in claim 7 , wherein the plastic bearing-housing-side diffuser wall ( 14 ), viewed in axial section, comprises
an inner wall region ( 17 ), which runs straight, and
a rounding ( 16 ) which runs from the straight inner wall region ( 17 ) to a straight region perpendicular to the straight inner wall region ( 17 ) adjoining an inner wall ( 15 ) of the compressor spiral ( 13 ) of the compressor housing ( 10 ).

Assignees

• Lischer Thomas
• Borgwarner Inc

Inventors

• Lischer Thomas

Classifications

• F02B37/18

  by bypassing exhaust {from the inlet to the outlet of turbine or to the atmosphere} · CPC title

• F05D2220/40

  in turbochargers · CPC title

• F04D29/601

  specially adapted for elastic fluid pumps · CPC title

• F02C6/12

  Turbochargers, i.e. plants for augmenting mechanical power output of internal-combustion piston engines by increase of charge pressure · CPC title

• F02B39/00 Primary

  Component parts, details, or accessories relating to, driven charging or scavenging pumps, not provided for in groups F02B33/00 - F02B37/00 · CPC title