U.S. patent application number 14/387912 was filed with the patent office on 2015-02-19 for systems and methods for protecting a turbocharger aluminum bearing housing.
This patent application is currently assigned to BorgWarner Inc.. The applicant listed for this patent is BorgWarner Inc.. Invention is credited to Brock Fraser, Mehul Sonigra.
Application Number | 20150049967 14/387912 |
Document ID | / |
Family ID | 49261115 |
Filed Date | 2015-02-19 |
United States Patent
Application |
20150049967 |
Kind Code |
A1 |
Fraser; Brock ; et
al. |
February 19, 2015 |
SYSTEMS AND METHODS FOR PROTECTING A TURBOCHARGER ALUMINUM BEARING
HOUSING
Abstract
In an aluminum turbocharger bearing housing, there is a
potential for wear of the bearing housing at the interface with the
turbine housing and/or the bearing system. One area of potential
concern is the interface between the flange of the bearing housing
and an abutment of the turbine housing. With a protective element
at the interface, the potential for wear, and thus misalignment of
the rotating assembly with the housings in which they operate can
be mitigated. The protective element can be a cap for the bearing
housing flange or a heat shield adapted to cover certain faces of
the bearing housing flange. The protective element can be a sleeve
provided within a bore in the bearing housing. The protective
element can be made of a material with a higher heat resistance
and/or a higher wear resistance than the aluminum bearing
housing.
Inventors: |
Fraser; Brock; (Asheville,
NC) ; Sonigra; Mehul; (Arden, NC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BorgWarner Inc. |
Auburn Hills |
MI |
US |
|
|
Assignee: |
BorgWarner Inc.
Auburn Hills
MI
|
Family ID: |
49261115 |
Appl. No.: |
14/387912 |
Filed: |
March 19, 2013 |
PCT Filed: |
March 19, 2013 |
PCT NO: |
PCT/US2013/032932 |
371 Date: |
September 25, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61616012 |
Mar 27, 2012 |
|
|
|
Current U.S.
Class: |
384/100 ;
384/456 |
Current CPC
Class: |
F05D 2240/15 20130101;
F04D 29/0473 20130101; F05D 2260/39 20130101; F04D 29/0462
20130101; F05D 2300/121 20130101; F05D 2220/40 20130101; F05D
2260/37 20130101; F01D 25/125 20130101; F01D 25/162 20130101; F01D
25/243 20130101 |
Class at
Publication: |
384/100 ;
384/456 |
International
Class: |
F04D 29/046 20060101
F04D029/046; F04D 29/047 20060101 F04D029/047 |
Claims
1. A protective system for a turbocharger interface comprising: a
first surface defined by a portion of an aluminum turbocharger
bearing housing (22); a second surface defined by a turbocharger
component; and a protective element operatively positioned between
the first and second surfaces, the protective element being made of
a material that has at least one of a higher heat resistance or a
higher wear resistance than the aluminum turbocharger bearing
housing, whereby the protective element protects the first surface
from heat and/or wear.
2. The system of claim 1, wherein the protective element is made of
one of: steel, cast iron or titanium.
3. The system of claim 1, wherein the first surface is defined by a
flange (42) of the aluminum turbocharger bearing housing (22).
4. The system of claim 3, wherein the protective element is a cap
(70) having a generally U-shaped cross-section, and wherein the cap
(70) covers at least a portion of the first surface of the flange
(42).
5. The system of claim 3, wherein the protective element is a cap
(70) having a generally V-shaped cross-section, and wherein the cap
(70) covers at least a portion of the first surface of the flange
(42).
6. The system of claim 1, wherein the protective element is a
sleeve (78) that is received in a bore (100) of the aluminum
turbocharger bearing housing (22).
7. The system of claim 1, wherein the protective element is a
turbine heat shield (46'), wherein the first surface includes a
turbine end facing face (112) and a radially mating face (116) of a
flange (42) of the aluminum turbocharger bearing housing (22) that
is transverse to the turbine end facing face (112), wherein the
second surface is defined by a turbine housing (14), wherein the
heat shield (46') includes an axially facing surface (114) and a
radially facing flange (118), and wherein the heat shield (46') is
operatively positioned between the first and second surfaces.
8. The system of claim 1, wherein the first surface is an outer
tapered surface (92) of a flange (42) of the aluminum turbocharger
bearing housing (22), and wherein the second surface is a portion
of a retainer segment (54) of a vee-band (56).
9. A method of protecting an interface in a turbocharger between a
first surface and a second surface, the first surface being defined
by a portion of an aluminum turbocharger bearing housing (22) and
the second surface defined by a turbocharger component, the method
comprising: providing a protective element made of a material that
has at least one of a higher heat resistance or a higher wear
resistance than the aluminum turbocharger bearing housing; and
operatively positioning the protective element between the first
and second surfaces such that at least a portion of the first
surface is protected from heat and/or wear.
10. The method of claim 9, wherein the protective element is made
of one of: steel, cast iron or titanium.
11. The system of claim 9, wherein the first surface is defined by
a flange (42) of the aluminum turbocharger bearing housing
(22).
12. The system of claim 9, wherein the protective element is a cap
(70), wherein the operatively positioning includes providing the
cap (70) over at least a portion of a radial surface (72), a first
axial surface (74) and/or a second axial surface (76) of the flange
(42).
13. The system of claim 12, wherein the cap (70) has one of
generally V-shaped cross-section or a generally U-shaped
cross-section.
14. The system of claim 9, wherein the protective element is a
sleeve (78) and the first surface is a bore (36) in the aluminum
turbocharger bearing housing (22), and wherein the sleeve (78)
covers at least a portion of the bore (100).
15. The system of claim 9, wherein the protective element is a
turbine heat shield (46'), wherein the first surface includes a
turbine end facing face (112) and a radially mating face (116) of a
flange (42) of the aluminum turbocharger bearing housing (22) that
is transverse to the turbine end facing face (112), wherein the
second surface is defined by a turbine housing (14), wherein the
heat shield (46') includes an axially facing surface (114) and a
radially facing flange (118), and wherein the heat shield (46') is
operatively positioned between the first and second surfaces such
that the axially facing surface (114) protects the turbine end
facing face (112) and such that the radially facing flange (118)
protects the radially mating face (116)).
16. The system of claim 9, wherein the first surface is an outer
tapered surface (92) of a flange (42) of the aluminum turbocharger
bearing housing (22), and wherein the second surface is a portion
of a retainer segment (54) of a vee-band (56).
Description
FIELD OF THE INVENTION
[0001] Embodiments relate in general to turbochargers, and, more
particularly, to turbochargers with bearing housings made of
aluminum.
BACKGROUND OF THE INVENTION
[0002] Turbochargers are a type of forced induction system. They
deliver air, at greater density than would be possible in the
normally aspirated configuration, to the engine intake, allowing
more fuel to be combusted, thus boosting the engine's horsepower
without significantly increasing engine weight. A smaller
turbocharged engine, replacing a normally aspirated engine of a
larger physical size, will reduce the mass and can reduce the
aerodynamic frontal area of the vehicle.
[0003] Referring generally to FIGS. 1 and 2, turbochargers (10) use
the exhaust flow from the engine exhaust manifold to drive a
turbine wheel (12), which is located within a turbine housing (14).
The energy extracted by turbine wheel (12) is translated to a
rotating motion, which then drives a compressor wheel (16), which
is located within a compressor cover (18). The compressor wheel
(16) draws air into the turbocharger (10), compresses this air, and
delivers it to the intake side of the engine. The rotating assembly
consists of the following major components: turbine wheel (12);
compressor wheel (16); a shaft (20) upon which the turbine wheel
(12) and compressor wheel (16) are mounted; journal bearings;
flinger; and thrust components. The shaft (20) rotates on a bearing
system which is fed oil, typically supplied by an engine oil pump.
The bearing system is located within a bearing housing (22).
Typically, there are two types of bearing systems--rolling element
bearing (REB) systems and hydrodynamic journal bearing systems.
[0004] A typical turbocharger (10) having a rolling element bearing
(REB) system (21) is shown in FIG. 1. The bearings are presented in
the form of a cartridge (30) in which the shaft (20) locates on the
inner race (24) of the cartridge (30), and the outer race (26) of
the cartridge (30) locates in a bore (36) in the bearing housing
(22). Typically, the outer diameter of the outer race (24) is
damped by an oil film between the outer diameter of the outer race
(26) and the inner diameter of the bore (36) in the bearing housing
(22). The axial constraint for the bearing cartridge (30) is an
abutment in the bearing housing (22) on one end thereof and a clip
(28) on the other end thereof. The clip (28) can also be used as an
anti-rotation constraint. The shaft (20) is located in the bearing
cartridge (30) by an abutment on the turbine-end of the shaft (20),
itself abutting an abutment on the turbine-end of the inner race
(24).
[0005] FIG. 2 shows a typical turbocharger having a hydrodynamic
journal bearing system (23). In such a configuration, the journal
bearings (32) and thrust bearing (34) are individually assembled
into the bearing housing (22). Both the outside diameter of the
journal bearing (32) and the shaft (20) (which is located within
the inside diameter of the journal bearing (32)) are supported by
oil films. Typically, the journal bearing bore (37) is finished to
a very high degree of cylindricity and surface finish. The axial
constraint in a typical journal bearing turbocharger (10) is
provided by a thrust bearing (34), which axially locates against an
abutment on the thrust bearing-end of the bearing housing (22). The
shaft axial position is set by a thrust washer (axially controlled
by the thrust bearing) abutting against an abutment on the
compressor-end of the journal bearing diameter on the shaft
(20).
[0006] Most turbochargers mount to an engine via the turbine
housing foot (38). In these cases, the forces exerted by the
bearing housing (22), compressor cover (18), and the rotating
assembly (including the rotating inertia) on the foot (38), and
thus the engine, are transmitted through the joint attaching the
turbine housing (14) to the bearing housing (22) so that particular
jointing interface is susceptible to wear. The axial position of
the turbine housing (14), relative to the bearing housing (22), is
set by a turbine housing facing surface (40) on the locating flange
(42) of the bearing housing (22), with the face of a complementary
abutment (44) on the turbine housing (14). In some cases, a flange
(42) on a turbine heat shield (46) is sandwiched between the
turbine housing abutment (44) and the surface (40).
[0007] The joint between turbine housing (14) and bearing housing
(22) is typically one of two types. The first type of joint is a
bolt and clamp-plate type of joint, as depicted in FIGS. 1, 2 and
3. In such an arrangement, a flange (42) is clamped on one part (of
the turbine housing or bearing housing) to the body of the
complementary part, with the clamp load supplied by a threaded
fastener (50) through a clamp plate (52).
[0008] The other type of joint for the turbine housing (12) to
bearing housing (22) interface is a vee-band, as depicted in FIG.
3. In this type of joint, a flange (42) of the bearing housing (22)
and a flange (64) of the turbine housing (14) are both axially and
radially constrained by the complementary tapers on a vee-band
retainer (56) and the flanges (42, 64) it pulls together. The
vee-band (56) typically has a plurality of retainer segments (54),
which are circumferentially compressed by a tee-bolt and trunnion.
This compression in the tee-bolt exerts a tensile stress in a band
the tee-bolt pulls the ends of the band (56) together. The force
exerted by the band (56) on the retainer segments (54) is
translated into a uniform closing force, with both a radially
inwards component and an axially contracting component. The radial
component pulls the vee-band flange retainer segments (54) down the
tapers (58, 59), fabricated into flanges (42, 64), in the two
components being clamped together (In this case, the turbine
housing (14) and the bearing housing (22)).
[0009] In either type of joint between turbine housing (14) and
bearing housing (22), the interface is subjected to a moment force
as well as vibration and temperature differences. Any wear in the
interface can cause a misalignment between the elements of the
rotating assembly (i.e. the turbine and compressor wheels (12, 16))
and the housings (14, 22) in which they reside.
[0010] In modern auto applications, the mass of the vehicle is
becoming a major issue when it comes to the efficiency of the
vehicle. In an effort to reduce the mass of a turbocharger, an
aluminum bearing housing was substituted for the former traditional
gray iron bearing housing. With exhaust temperatures in the range
of 700.degree. C. to 1050.degree. C., the turbine housing could not
be cast in aluminum. This change in material produced a mass
reduction in the range of 55% to 65% for the bearing housing and a
potential reduction in moment about the interface of the turbine
housing to the bearing housing of approximately 33%. However, in
doing so, there can be increased wear at the interface between the
hot turbine housing (14) and the relatively cool bearing housing
(22) and also at the interface of the bearing housing (22) to any
bearing system that may be implemented, as aluminum is relatively
soft compared to gray iron. Thus, referring to the interface
between the turbine housing (14) and the bearing housing (22) shown
in FIG. 3 as an example, the interaction of the inner surfaces of
the retainer segments (54) on the tapers (58, 59) of the flanges
(42, 64), particularly the aluminum bearing housing flange (42),
can damage the surface of the flange (42) and be detrimental to a
subsequent application of the vee-band (56) to the flange (42).
[0011] Thus, there is a need for systems and methods that can
permit the use of an aluminum bearing housing in a turbocharger
while providing a suitable interface with the turbine housing and
the bearings.
SUMMARY OF THE INVENTION
[0012] Embodiments described herein facilitate the use of an
aluminum bearing housing by providing systems and methods for
protecting the interface between the bearing housing and the
turbine housing and/or between the bearing housing and the bearing
system, thereby avoiding wear and other issues that may arise from
the use of an aluminum bearing housing while allowing the
advantages of such a bearing housing to be realized. Systems and
methods provide a protective surface of steel or other suitable
materials in the interface to protect the aluminum surfaces that
would otherwise form the interface. Suitable materials have a
higher heat resistance and/or a higher wear resistance than the
base aluminum material of the bearing housing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The present invention is illustrated by way of example and
not limitation in the accompanying drawings in which like reference
numbers indicate similar parts, and in which:
[0014] FIG. 1 is a cross-sectional view of a typical turbocharger
assembly with rolling element bearings;
[0015] FIG. 2 is a cross-sectional view of a typical turbocharger
assembly with a hydrodynamic bearing;
[0016] FIG. 3 shows a typical vee-band type of clamping system for
the turbine housing and the bearing housing;
[0017] FIG. 4 shows a first embodiment of a protective system for
an interface between an aluminum bearing and a turbine housing
and/or a bearing system;
[0018] FIG. 5 shows a second embodiment of a protective system for
an interface between an aluminum bearing and a turbine housing;
and
[0019] FIG. 6 shows a third embodiment of a protective system for
an interface between an aluminum bearing and a turbine housing
and/or a bearing system.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Arrangements described herein relate to device turbocharger
with an aluminum bearing housing configured for improved interface
with the turbine housing and/or bearing system. Detailed
embodiments are disclosed herein; however, it is to be understood
that the disclosed embodiments are intended only as exemplary.
Therefore, specific structural and functional details disclosed
herein are not to be interpreted as limiting, but merely as a basis
for the claims and as a representative basis for teaching one
skilled in the art to variously employ the aspects herein in
virtually any appropriately detailed structure. Further, the terms
and phrases used herein are not intended to be limiting but rather
to provide an understandable description of possible
implementations. Arrangements are shown in FIGS. 4-6, but the
embodiments are not limited to the illustrated structure or
application.
[0021] Referring to FIG. 4, examples of protective systems for an
interface between an aluminum bearing housing (22) and a turbine
housing (14) and/or a bearing system (not shown) are shown. The
bearing housing (22) can be made of any suitable type of
aluminum.
[0022] A protective element (70) can be operatively positioned
between at least a portion the aluminum bearing housing, such as
the flange (42), that contacts the turbine housing (14). The
protective element (70) can be made of any suitable material. For
instance the protective element (70) can be made of a material that
has a higher heat resistance and/or a higher wear resistance than
the aluminum of the bearing housing (22). For instance, the
protective element (70) can be made of cast iron, titanium, or any
suitable type of steel. The protective element (70) can be made of
a material that it harder than the aluminum bearing housing (22).
The protective element (70) can provide resistance to potential
wear problems between the turbine housing (14) and the relatively
soft aluminum bearing housing (22). The protective element (70) may
also provide protection to the aluminum bearing housing (22) from
the heat of the turbine housing (14).
[0023] The protective element (70) can have any suitable
conformation. In one embodiment, the protective element (70) can be
configured like a cap having a generally U-shaped cross-section, as
is shown in FIG. 4. In such case, the protective element (70) can
cover at least a portion of the bearing housing (22), such as
flange (42). In such case, the protective element (70) can include
a generally cylindrical radially protecting surface (72), and one
or more axially protecting surfaces (74,76). In the arrangement
shown in FIG. 4, two axially protecting surfaces (74, 76) are
provided, but embodiments are not limited to there being two
axially protecting surfaces. The pair of axially protecting
surfaces (74,76) can be generally transverse to the generally
cylindrical radially protecting surface (72). In one embodiment,
the pair of axially protecting surfaces (74,76) can at
substantially 90 degrees to the generally cylindrical radially
protecting surface (72). Naturally, the surfaces (72, 74, 76) can
extend at any suitable any relative to each other, depending on the
configuration of the bearing housing (22) and/or other components
at the interface.
[0024] The surfaces (72, 74, 76) can be formed together as a
unitary structure, or at least one of the surfaces (72, 74, 76) can
be defined by a separate piece and joined to the other surface
defining piece(s). The protective element (70) can be a ring-like
structure. The protective element (70) can be made as a single
piece or a plurality of circumferential ring segments, that is, in
a direction about the axis (98) of the bore (100) in the aluminum
bearing housing (22). Again, it will be understood that the
above-description of the protective element (70) is provided merely
as an example, and embodiments are not limited to this
configuration. In some instances, the protective element (70) can
be formed by applying (e.g. spraying) a suitable metal over at
least a portion of the aluminum flange (42), which could have
reduced dimensions to accommodate the thickness of the protective
element (70). Alternatively, the protective element (70) can be
cast in place over at least a portion of the flange (42) of the
bearing housing (22). In at least some instances, the protective
element (70) can be attached to the bearing housing (22) in any
suitable manner, including, for example, by fasteners, adhesives,
and/or mechanical engagement, just to name a few possibilities.
[0025] Alternatively or in addition to the protective element (70),
the system can be configured to minimize wear of a bore (100) in
the aluminum bearing housing (22) by providing a protective sleeve
(78) therein. Thus, the sleeve (78) can be operatively positioned
between the bore (100) and any bearing system (not shown). The
sleeve (78) can be made of any suitable material. For instance, the
sleeve (78) can be made of a material that has a higher heat
resistance and/or a higher wear resistance than the aluminum of the
bearing housing (22). For instance, the sleeve (78) can be made of
cast iron, titanium, or any suitable type of steel. The sleeve (78)
can be made of a material that has a hardness greater than the base
aluminum metal of the bearing housing (22). The sleeve (78) can
have a turbine end (80) and a compressor end (82). The sleeve (78)
can be hollow and have any suitable cross-sectional size and/or
shape. The sleeve (78) can have a wall of any suitable
thickness.
[0026] The sleeve (78) can be provided in the bore (100) in any
suitable manner. For instance, the sleeve (78) can be cast in place
within the bore (100). Alternatively, the sleeve (78) can be
inserted into the bore (100) and attached by, for example, press
fit, interference fit, fasteners, adhesives, and/or mechanical
engagement, just to name a few possibilities. The sleeve (78) can
be formed by applying (e.g., spraying), a suitable metal over at
least a portion of the bore (100), which can have increased
dimensions.
[0027] The sleeve (78) can be formed as a single component, or it
can be formed by a plurality of sleeve segments that are joined
together in any suitable manner. The sleeve (78) can include
accommodations for other components. For instance, the sleeve (78)
can include passages (84) for fluid connection of the journal
bearing oil delivery ports (86) to the oil delivery galleries (87).
Further, the sleeve (78) can be configured to allow spent oil out
of the bearing system, such as by slots (88) formed in the sleeve
(78). In a similar fashion, the turbine-end (80) of the sleeve (78)
must have accommodation for a step bore (90) and accommodation for
the exit of oil flung off the turbine-end flinger of the shaft
(20)(see FIG. 2). The turbine-end (80) of the sleeve (78) would be
part of the main sleeve, but it could be a separate component.
[0028] Referring to FIG. 5, another example of a protective system
for an interface between the aluminum bearing housing (22) and the
turbine housing (14) for a vee-band type of clamping is shown. Such
an arrangement can resist damage caused by the inner surface of the
retainer segment (54) on the outer tapered surface (92) of the
aluminum flange (42). A protective element (94) can be provided to
form a protective surface over at least a portion of the aluminum
flange (42). The outer tapered surface (96) provided by the
protective element (94) in this configuration can be in direct
contact with the inner surface of the retainer (54), thus
minimizing wear and damage to the aluminum flange (42), thereby
avoiding hindrances to the correct sliding mechanism required of
the vee-band configuration. The protective element (94) can be made
of any suitable material. For instance the protective element (94)
can be made of a material that has a higher heat resistance and/or
a higher wear resistance than the aluminum of the bearing housing
(22). For instance, the protective element (94) can be made of cast
iron, titanium, or, any suitable type of steel. The protective
element (94) can be made of a material that it harder than the
aluminum bearing housing (22).
[0029] The protective element (94) can have any suitable
conformation. In one embodiment, the protective element (94) can be
configured like a cap for the flange (42) in a vee-band
configuration. The protective element (94) can have a generally
v-shaped cross-section, as is shown in FIG. 5. The protective
element (94) can include first and second inner surfaces (102,
104). The first and second inner surfaces (102, 104) can be angled
relative to each other. In the embodiment shown in FIG. 5, an acute
angle is formed between the first and second inner surfaces (102,
104). The first and second inner surfaces (102, 104) can be
connected by a third inner surface (106). The protective element
(94) can be configured to cover at least a portion of the flange
(42). The protective element (94) can have any suitable
thickness.
[0030] The protective element (94) can be formed in any suitable
manner. For instance, the protective element (94) can be formed as
separate component that is placed over the aluminum flange (42).
The protective surfaces provided by the protective element (94) can
be a single piece construction or it can be made of a plurality of
pieces. The protective element (94) can be a ring-like structure.
It can be made as a single piece or a plurality of circumferential
ring segments, that is, in a direction about the axis (98) of the
bore (100) in the aluminum bearing housing (22). Again, it will be
understood that the above-description of the protective element
(94) is provided merely as an example, and embodiments are not
limited to this configuration. In some instances, the protective
element (94) can be formed by applying (e.g. spraying) a suitable
metal over at least a portion of the aluminum flange (42), which
could have reduced dimensions to accommodate the thickness of the
protective element (94). Alternatively, the protective element (94)
can be cast in place over at least a portion of the flange (42) of
the bearing housing (22). In at least some instances, the
protective element (94) can be attached to the bearing housing (22)
in any suitable manner, including, for example, by fasteners,
adhesives, and/or mechanical engagement, just to name a few
possibilities.
[0031] Referring to FIG. 6, additional examples of protective
systems for an interface between an aluminum bearing housing (22)
and a turbine housing (14) and/or a bearing system (not shown) are
shown. Here, the turbine heat shield (46') can be modified from the
typical design so as to provide a protective buffer, both axially,
in the direction of the compressor cover, and radially, for the
aluminum bearing housing (22) interface with the turbine housing
(14). In this arrangement, there may be no fixed protective cover
on the bearing housing (22), but the turbine-end facing axial
mating face (112) of the bearing housing flange (42) (with the
complementary abutment (44) in the turbine housing (14)) can be
protected by an extended axially facing surface (114) of the
turbine heat shield (46').
[0032] The surface of radial mating face (116) of the bearing
housing flange 42) (with the complementary pilot diameter in the
turbine housing (14)) can be protected by the extension portion
(110) by a further extended radially facing flange (118) of the
turbine heat shield (46') continuing from the extended axially
facing surface (114) of the turbine heat shield (46'). The heat
shield (46') can be formed in any suitable manner.
[0033] Further, the compressor facing side (120) of the flange (42)
can be protected by either clamp plates (52), which can have a
large surface area, or by parts of a segmented ring to spread the
clamp load from the nut (54) and clamp plate (52) to minimize wear
on the aluminum flange surface.
[0034] Alternatively on in addition to the heat shield (46'), the
protective system can include a sleeve (78). The above discussion
of the sleeve (78) made in connection with FIG. 6 is equally
applicable here.
[0035] The heat shield (46') can be made of any suitable material.
For instance the heat shield (46') can be made of a material that
has a higher heat resistance and/or a higher wear resistance than
the aluminum of the bearing housing (22). For instance, the heat
shield (46') can be made of cast iron, titanium, or any suitable
type of steel.
[0036] It will be appreciated that embodiments herein can provide
numerous benefits. For instance, by providing the protective
interfaces described herein, various areas of an aluminum bearing
housing (22) can be protected from wear. Thus, an aluminum bearing
housing (22) can be used in a turbocharger, thereby allowing for
mass reduction and the associated reduction in the moment carried
on the turbine housing to bearing housing interface.
[0037] The terms "a" and "an," as used herein, are defined as one
or more than one. The term "plurality," as used herein, is defined
as two or more than two. The term "another," as used herein, is
defined as at least a second or more. The terms "including" and/or
"having," as used herein, are defined as comprising (i.e., open
language).
[0038] Aspects described herein can be embodied in other forms and
combinations without departing from the spirit or essential
attributes thereof. Thus, it will of course be understood that
embodiments are not limited to the specific details described
herein, which are given by way of example only, and that various
modifications and alterations are possible within the scope of the
following claims.
* * * * *