U.S. patent application number 13/812618 was filed with the patent office on 2013-05-23 for multi piece turpocharger housing.
This patent application is currently assigned to SCHAEFFLER TECHNOLOGIES AG & CO. KG. The applicant listed for this patent is Richard Baier, Klaus Daut, Richard Haschke. Invention is credited to Richard Baier, Klaus Daut, Richard Haschke.
Application Number | 20130129479 13/812618 |
Document ID | / |
Family ID | 44119197 |
Filed Date | 2013-05-23 |
United States Patent
Application |
20130129479 |
Kind Code |
A1 |
Daut; Klaus ; et
al. |
May 23, 2013 |
MULTI PIECE TURPOCHARGER HOUSING
Abstract
A turbocharger casing including a first casing part, wherein an
oil line starts at a first opening on an outer side of the first
casing part, runs through the first casing part and opens out at a
second opening of a substantially hollow-cylindrical bearing
receptacle of the first casing part. Such turbocharger casings of
the prior art are produced in a complicated manner by a sand
casting process and therefore give rise to high production costs.
The teaching is to arrive, without functional losses, at a
simple-to-produce and cost-effective turbocharger casing by the
turbocharger casing having a second casing part attached to the
first casing part and by both casing parts together forming a
cooling water line provided for cooling the bearing receptacle. It
is thus possible to arrive at a lightweight turbocharger casing by
conventional machining production methods and joining technique,
and this turbocharger casing can be produced cost-effectively.
Inventors: |
Daut; Klaus;
(Herzogenaurach, DE) ; Haschke; Richard;
(Heroldsbach, DE) ; Baier; Richard; (Aurachtal,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Daut; Klaus
Haschke; Richard
Baier; Richard |
Herzogenaurach
Heroldsbach
Aurachtal |
|
DE
DE
DE |
|
|
Assignee: |
SCHAEFFLER TECHNOLOGIES AG &
CO. KG
Herzogenaurach
DE
|
Family ID: |
44119197 |
Appl. No.: |
13/812618 |
Filed: |
May 23, 2011 |
PCT Filed: |
May 23, 2011 |
PCT NO: |
PCT/EP11/58348 |
371 Date: |
January 28, 2013 |
Current U.S.
Class: |
415/110 ;
415/116 |
Current CPC
Class: |
F05D 2230/238 20130101;
F05D 2230/64 20130101; F02C 6/12 20130101; F01D 25/24 20130101;
F01D 25/18 20130101; F05D 2220/40 20130101; F01D 25/246 20130101;
F05D 2230/237 20130101; F01D 25/125 20130101; F05D 2250/42
20130101; F02C 7/06 20130101; F05D 2230/232 20130101; F01D 25/145
20130101; F01D 25/14 20130101 |
Class at
Publication: |
415/110 ;
415/116 |
International
Class: |
F01D 25/24 20060101
F01D025/24 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 6, 2010 |
DE |
10 2010 033 665.3 |
Claims
1-10. (canceled)
11. A turbocharger housing comprising: a first housing part, an oil
duct starting at a first opening of an outer side of the first
housing part, extending right through the first housing part to
open at a second opening into a substantially hollow cylindrical
bearing receptacle of the first housing part, and a second housing
part connected to the first housing part, the first and second
housing parts together forming a cooling water conduit for cooling
the bearing receptacle.
12. The turbocharger housing as recited in claim 11 wherein the
second housing part is connected to the first housing part by at
least one of gluing, welding, crimping and soldering.
13. The turbocharger housing as recited in claim 12 wherein
connection of the second housing part to the first housing part is
formed by two connecting seams extending along the cooling water
conduit.
14. The turbocharger housing as recited in claim 11 wherein the
cooling water conduit and the oil duct of the first housing part
are machine finished.
15. The turbocharger housing as recited in claim 11 wherein the
first housing part connectable to at least one of a cold housing
and a hot housing.
16. The turbocharger housing as recited in claim 15 wherein the
first housing part is screwable to the hot housing using spacing
bushings.
17. The turbocharger housing as recited in claim 15 further
comprising a third housing part forming a fixing adapter for fixing
the first housing part to the hot housing.
18. The turbocharger housing as recited in claim 17 further
comprising a fixing element both for screwing the first housing
part to the hot housing and for fixing the third housing part to
the first housing part.
19. The turbocharger housing as recited in claim 11 wherein the
second housing part or a third housing part is made out sheet metal
or out of a forged part.
20. A turbocharger comprising: a bearing for a common shaft of a
compressor; a turbine; and the turbocharger housing as recited in
claim 11, the bearing being arranged in the bearing receptacle.
Description
[0001] The invention concerns a turbocharger housing in which an
oil duct starts at a first opening of an outer side of the first
housing part, extends right through the first housing part to open
at a second opening into a substantially hollow cylindrical bearing
receptacle of the first housing part. The invention further
concerns a turbocharger comprising such a housing.
BACKGROUND
[0002] Turbochargers are used for improving the performance of
internal combustion engines in which the kinetic energy of the
exhaust gas stream is extracted with help of a turbine and is used
to press the fuel-air mixture into the internal combustion engine
with help of a common shaft of the turbine and of a compressor. In
this way, the fixed cubic capacity of the internal combustion
engine can be filled with larger quantity of the mixture so that a
higher lifting force and thus also a higher engine performance is
achieved during combustion.
[0003] In passenger vehicles, turbochargers or rather the shaft of
the turbocharger reaches a speed of rotation of more than 200,000
rotations per minute. In the case of utility vehicles, this value
is in the order of magnitude of 150,000 rotations per minute. As a
rule, the shaft of the turbocharger is mounted in the turbocharger
housing through a sliding bearing, with the consequence that a
large amount of friction energy is released in the form of heat
exactly inside the bearing receptacle of the turbocharger housing.
Moreover, the turbocharger housing is situated between the
so-called hot housing and the cold housing. In the hot housing, the
exhaust gas stream is routed to the turbine so that additional heat
is transmitted through the hot exhaust gas stream to the hot
housing. During operation, a temperature of typically 1050.degree.
C. prevails in the hot housing and in the cold housing, in
contrast, where the fuel-air mixture is compressed, the prevailing
temperature is approximately 20.degree. C.
[0004] For these reasons, it is necessary to cool the turbocharger
housing with help of a water cooling, sustainably and in particular
in the vicinity of the bearing receptacle. On the one hand, it must
be prevented that heat finds its way out of the exhaust gas stream
via the turbocharger housing into the cold housing, which can
typically also take place via the shaft. On the other hand, it is
also necessary to discharge the friction heat that is produced in
the sliding bearing. An eventual failure of the cooling of the
turbocharger housing creates a risk of damage to the sliding
bearing and a premature ignition of the fuel-air mixture in the
cold housing.
[0005] WO 2009/013332 A3 discloses a turbocharger comprising a
housing, said housing being destined to receive a sliding bearing
for the shaft of the turbocharger. This housing substantially
comprises a cast part that contains a water conduit for cooling the
bearing receptacle. The larger part of the water cooling is
completely surrounded by the housing both in radial and in axial
direction.
[0006] Turbocharger housings made out of cast metal do indeed
manifest an excellent thermal conductivity but possess, on the
other hand, a heavy weight and give rise to very high manufacturing
costs precisely due to the very complex integration of the cooling
water conduit which, however, is indispensable.
SUMMARY OF THE INVENTION
[0007] It is an object of the present invention is to provide a
turbocharger housing of a lighter weight that is simple and
economic to manufacture without prejudicing the mode of functioning
of the turbocharger housing.
[0008] The present invention procides a turbocharger housing of the
pre-cited type by the fact that the turbocharger housing comprises
a second housing part connected to the first housing part, and said
two housing parts together form a cooling water conduit for cooling
the bearing receptacle.
[0009] According to the invention, an oil supply arrangement in
form of an oil duct is disposed in the turbocharger housing and
serves to supply oil to the bearing arranged in the hollow
cylindrical bearing receptacle. For this purpose, the first housing
part comprises a first opening that is arranged on an outer side of
the first housing part. The oil duct begins at this first opening
and extends right through the first housing part. This oil duct can
be realized or configured in the first housing part, for example,
through appropriate bores. The oil duct ends at a second opening of
the first housing part and opens into the substantially hollow
cylindrical bearing receptacle. The bearing receptacle, too, is
configured on the first housing part by a machining method, for
example by boring. If necessary, diverse grooves or annular
configurations are provided on the hollow cylindrical inner surface
of the bearing receptacle so that, if need be, the bearing
receptacle deviates from the substantially hollow cylindrical
shape. The second opening thus constitutes the opening of the oil
duct into the bearing receptacle so that the sliding or rolling
bearing of the turbocharger can be supplied with oil.
[0010] In the case of sliding bearing mounted turbochargers, for
instance, the lubricant oil is pressed from outside under
appropriate pressure into the bearing receptacle so that a
so-called squeezable film is formed between the bearing receptacle
and the sliding rings and migrates further little by little in
axial direction till it finally leaves the sliding bearing.
[0011] In addition to the first housing part, the turbocharger
housing according to the invention also comprises a second housing
part that is connected to the first housing part. The connection
can be realized through a known joining method, for example by
welding, gluing, crimping and/or soldering. Laser welding is
particularly suitable because this guarantees an industrial
manufacturing with a very short manufacturing time. The connection
of the second housing part to the first housing part results in the
formation of a cooling water conduit that is provided for cooling
the bearing receptacle. In other words, a part of the outer surface
of the first housing part and a further part of the outer surface
of the second housing part together form the inner wall of the
cooling water conduit. This has the advantage that the cooling
water conduit does not have to be manufactured by a complex and
expensive casting method but both the housing parts made according
to the invention can be manufactured by usual machining methods or
by shaping technics and can be connected to each other after this
finishing step.
[0012] Advantageously, the first housing part is made out of a
forged part by a machining method, for instance boring, turning
and/or milling. Alternatively, the first housing part may also be
made out of sheet metal in which case, care must be taken to assure
a heat flow and a cooling effect. The second housing part can
likewise be manufactured by a particularly low-cost method by
configuring it as a sheet metal part, in particular as a
cold-formed sheet metal part. By reason of the possibility of using
machining methods, it also becomes possible, in contrast to the
cooling chamber in the interior of conventional cast parts, to
clearly enlarge the cross-section of the cooling water conduit with
very close manufacturing tolerances so that it is advantageously
possible through the invention to achieve a cooling water
through-put of up to four times the through-put hitherto possible,
while keeping the outer dimensions unchanged.
[0013] In one advantageous form of embodiment of the invention, the
connection of the second housing part to the first housing part is
constituted by two connecting seams extending along the cooling
water conduit. A connecting seam results from one of the joining
methods used. In the case of welding, for instance, this would be a
weld seam and, in the case of gluing, a glued seam, etc. An
advantage of these methods over casting in sand is that the hollow
spaces of the cooling water conduit do not have to be subsequently
freed from residual sand under high water pressure. In addition,
bores for removing the sand core are not required in the first
place.
[0014] The connecting seam must not only guarantee the structural
stability of the turbocharger housing but also assure a tightness
of the cooling water conduit that excludes a leakage of cooling
water under the conditions prevailing during operation. In this
sense, the connecting seams also have a sealing function.
[0015] If the second housing part is made partially or completely
out of sheet metal, it is not necessary to conduct a heat flow
through the connecting seam because the sheet metal, due to its
small thickness, can absorb only a relatively small amount of heat.
Cooling therefore takes place via the water conduit mainly through
the first housing part. Alternatively, the first and the second
housing part are made as cast parts so that both housing parts can
accommodate and conduct larger heat streams, and this can become
necessary depending on the turbocharger application. Alternatively,
for example, if temperature load is low, the first and the second
housing part may also be made out of sheet metal.
[0016] Advantageously, the first housing part is intended for
connecting to a cold housing and/or a hot housing. From the point
of view of assembly, it is appropriate to screw the cold housing,
the hot housing and the turbocharger housing to one another. The
connections between these housings may, however, be realized
through other known fixing means. It is, however, important that a
housing part of the turbocharger housing eventually made out of
sheet metal does not participate in the transmission of the torque
of the screw connection. Therefore, for example, spacing bushings
for screwing the first housing part to the hot housing or the cold
housing are advantageously used in this type of fixation for
by-passing a sheet metal housing part. The spacing bushings thus
substantially outline the axial width of the second housing part
that has to be spanned by this fixation. The advantage of this is
that the second housing part, due to a smaller overall contact
surface, must not participate at all, or only to a small extent, in
a heat transmission from the hot housing to the turbocharger
housing part but, rather, a further advantageous insulation is
produced due to the distance and due to the spacing bushings.
Moreover, spacing bushings are particularly suitable for taking up
joining and vibration forces that can be produced during assembly
and operation.
[0017] Depending on the case of use, it is possible instead of
using spacing bushings to make the second housing part more stable
(e.g. double walls or the like) so that the second housing part can
be braced between the first housing part and the hot housing.
[0018] In a further advantageous form of embodiment, a third
housing is provided for forming a fixing adapter for fixing the
first housing part to the cold housing. Basically, it is possible
to configure the first housing part such that a direct fixing on
the cold housing is possible. Because, however, this third housing
can optionally also be formed out of sheet metal, a further cost
advantage is created due to the multi piece structure. Fixing of
the third housing part on the first housing part may also be
realized through screwing or laser welding or any other type of
mechanical connection.
[0019] In a further advantageous form of embodiment, a fixing means
like, for instance, a screw is used both for screwing the first
housing part to the hot housing and for fixing the third housing
part to the first housing part. This simplifies the fixing of the
turbocharger housing in a two piece or multi piece configuration
because the same fixing means can be used in both cases.
[0020] The turbocharger housing of the invention can be used both
in rolling bearing mounted and in sliding bearing mounted
turbochargers. The turbocharger housing can still be made out of
more than two or three parts, each part being specially intended
for one or more functions. What is important is that one of the
housing parts constituting the cooling water conduit has an
adequate mass for assuring an optimal conduction of heat to the
cooling water conduit.
[0021] Further advantages and preferred developments of the
invention can be seen in the description of the figures and/or the
dependent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The invention will now be described and explained more
closely in the following with reference to the forms of embodiment
illustrated in the appended drawings. The figures show:
[0023] FIG. 1, a sliding bearing mounted turbocharger comprising a
three piece turbocharger housing, in a longitudinal section along
the axis of rotation,
[0024] FIG. 2, the first housing part of the turbocharger housing
of FIG. 1 made as a machine-finished forged part, in a longitudinal
section along the axis of rotation,
[0025] FIG. 3, the first housing part of the turbocharger housing
of FIG. 1, as viewed along the vertical axis,
[0026] FIG. 4, the first housing part of the turbocharger housing
of FIG. 1, as viewed along the axis of rotation,
[0027] FIG. 5, the second housing part of the turbocharger housing
of FIG. 1, as viewed along the axis of rotation,
[0028] FIG. 6, the second housing part of the turbocharger housing
of FIG. 1, in a first sectional illustration vertical to the axis
of rotation,
[0029] FIG. 7, the second housing part of the turbocharger housing
of FIG. 1, in a second sectional illustration vertical to the axis
of rotation,
[0030] FIG. 8, the third housing part of the turbocharger housing
of FIG. 1, as viewed along the axis of rotation, and
[0031] FIG. 9, the third housing part of the turbocharger housing
of FIG. 1, in a sectional illustration vertical to the axis of
rotation.
DETAILED DESCRIPTION
[0032] FIG. 1 shows a sliding bearing mounted turbocharger
comprising a three piece turbocharger housing, in a longitudinal
section along the axis of rotation R. The first housing part 15 of
the turbocharger housing is configured as a machine-finished forged
part, in longitudinal section along the axis of rotation R.
[0033] The turbocharger housing comprises the first housing part
15, the second housing part 7 and the third housing part 16. The
turbocharger housing is arranged between the cold housing 1 and the
hot housing and screwed to both of these housings.
[0034] The shaft 19 connects the turbine 10, which is arranged in
the hot housing 12, to the compressor 17 which is fixed on the
shaft 19 with help of a fixing element 18, e.g. a nut. The shaft 19
is configured in one piece with turbine 10 so that, due to heat
conduction, a basic danger of heat migrating out of the hot housing
12 into the cold housing 1 exists.
[0035] The water conduit 11 comprises a sectional surface of a
square or at least rectangular shape, possesses a substantially
annular shape and surrounds a part of the sliding bearing in radial
direction. The water conduit 11 is also often called cooling
chamber or water pocket. The water conduit 11 is formed and defined
partially by the first housing part 15 and partially by the second
housing part 7. The connecting seams 9, 14 are made through a
joining method such as, for example, laser welding and lead to a
structural stability of the turbocharger housing while additionally
sealing the water conduit 11 so that cooling water can exit.
[0036] The connecting element 13 is substantially configured in the
form of a tube and welded to the second housing part 7. The
connecting element 13 provides an advantageous connecting junction
for a cooling water hose. The connecting element 13 can function
optionally as an inlet or an outlet.
[0037] The third housing part 16 is configured as a sheet metal
part which leads to a cost advantage because a relatively favorable
cold shaping replaces a machining fabrication method.
Alternatively, the third housing part 16 can be configured in one
piece with the first housing part 15 in so far as a multi piece
configuration is not desired or if, for example, the turbocharger
housing is desired to have a two piece structure.
[0038] The third housing part 16 is pressed in radially into the
cold housing 1 and additionally screwed to this.
[0039] The sliding bearing of the turbocharger comprises sliding
bearing rings 8 that are supplied with oil through oil ducts 3, 5.
The spacers used are in the form of spacing rings 6.
[0040] FIGS. 2 to 4 show the first housing part 15 in different
views. The first housing part 15 is a forged part comprising a
lubricant duct system which is subsequently configured in the form
of bores in the forged part. The oil duct 3 comprises a first
opening 2 on an outer surface of the housing part 15, extends
radially towards the axis of rotation R and branches into an
inclined oil duct 5 that extends substantially in axial direction
but also slightly inclined relative to the axis of rotation to open
into the bearing receptacle 20 at an opening, not referenced.
[0041] The outer radii of the housing part 15 are made by turning
which means that they are likewise made by a machine finishing. An
advantage of this is that the thus obtained cylindrical and
disk-like surface can be finished with a very high precision and,
together with the second housing part, not shown, can form a water
conduit that can thus also be realized with a very high
precision.
[0042] In FIG. 4, the direction of viewing extends along the axis
of rotation to the side of the first housing part 15 facing the
cold housing 1. To be seen are bores 24 that extend with variable
bore spacing relative to one another (as projected on the
horizontal axis Z and the vertical axis Y respectively). The bores
24 serve on the one hand to attach the third housing part and, on
the other hand, to connect the first housing part to the cold
housing and the hot housing. The variable bore spacing chosen
assures that the components are screwed together with the correct
relative orientation. A combination of the bore spacings A, B, C
assures that the components are always in the correct position
relative to one another.
[0043] FIGS. 5 to 7 show the second housing part 7 in different
views. The second housing part 7 substantially possesses the shape
of a bushing whose bushing bottom comprises a depression that
projects axially out of the bushing and in which a bore 23 has been
made.
[0044] Further, the second housing part 7 comprises in the
cylindrical part an opening 22 and/or an opening comprising a
connecting element 21. Through such openings, it is assured that
the cooling water can flow into the water conduit 11 that is formed
partially by the second housing part 7.
[0045] The edges of the bore 23 as also the edges of the opposing
(largest) circular opening of the second housing part 7 participate
in so far in the welding joint with the first housing part 15 that
a part of the material, in addition to the material specially
brought in by the joining step, likewise contributes to forming the
weld seam. It can be seen that the connecting seams are two closed,
i.e. annular joints.
[0046] FIGS. 8 and 9 show the third housing part 16 of the
turbocharger housing comprising four bores 25 that are arranged
identically to the bores 24 of the second housing part. During the
screwing of the first housing part 15 to the hot housing 12, it is
thus possible to fix the third housing part 16 on the first housing
part in the same work step. For this purpose, four screws must
first be inserted through bores, not shown, of the cold housing 1,
after this, through the bores 25, following this, through the bores
24 and then through spacing bushings, not shown, to be finally
screwed into the hot housing 12. In this way, four screws are
sufficient for assembling the entire turbocharger.
[0047] The third housing part 16 comprises, radially inside, a
cylindrical axial extension 26 that serves for the axial spacing of
the cold housing 1. The outer periphery of the third housing part
16 that is configured as a fixing adapter is chosen such that the
third housing part 16 can be pressed into the cold housing 1. This
simplifies assembly during which the third housing part 16 fulfills
a retaining function as long as the screwed connection has not been
made.
LIST OF REFERENCE NUMERALS
[0048] 1 Cold housing
[0049] 2 First opening
[0050] 3 Oil duct
[0051] 4 Second opening
[0052] 5 Inclined oil duct
[0053] 6 Spacing ring
[0054] 7 Second housing part
[0055] 8 Sliding bearing
[0056] 9 Connecting seam
[0057] 10 Turbine
[0058] 11 Cooling water conduit
[0059] 12 Hot housing
[0060] 13 Connecting element
[0061] 14 Connecting seam
[0062] 15 First housing part
[0063] 16 Third housing part
[0064] 17 Compressor
[0065] 18 Fixing element
[0066] 19 Shaft
[0067] 20 Bearing receptacle
[0068] 21 Connecting element
[0069] 22 Opening
[0070] 23 Bore
[0071] 24 Bore
[0072] 25 Bore
[0073] 26 Axial extension
[0074] A Bore spacing
[0075] B Bore spacing
[0076] C Bore spacing
[0077] R Axis of rotation
[0078] Y Vertical axis
[0079] Z Horizontal axis
* * * * *