U.S. patent application number 11/970054 was filed with the patent office on 2009-02-19 for method of manufacturing split bearing races.
This patent application is currently assigned to GM Global Technology Operations, Inc.. Invention is credited to Jeffrey R. Lee, Travis M. Thompson.
Application Number | 20090046968 11/970054 |
Document ID | / |
Family ID | 40363025 |
Filed Date | 2009-02-19 |
United States Patent
Application |
20090046968 |
Kind Code |
A1 |
Lee; Jeffrey R. ; et
al. |
February 19, 2009 |
Method of Manufacturing Split Bearing Races
Abstract
A method of manufacturing or forming a split bearing race for an
angular contact roller bearing is provided. The method includes the
steps of: A) forming a generally annular blank having a first
annular portion, a second annular portion, and a third annular
portion disposed between the first and second annular portions, the
third annular portion having a thickness greater than the thickness
of the first and second annular portions; B) machining at least one
of the first, second, and third annular portions; and C) forming a
first and second race member of the split bearing race by
bifurcating the generally annular blank along the third annular
portion. The method may also include the steps of: D) heat treating
the generally annular blank after machining at least one of the
first, second, and third annular portions; and E) finish machining
the generally annular blank subsequent to the heat treating.
Inventors: |
Lee; Jeffrey R.; (Tipton,
MI) ; Thompson; Travis M.; (Ann Arbor, MI) |
Correspondence
Address: |
Quinn Law Group, PLLC
39555 Orchard Hill Place, Suite 520
Novi
MI
48375
US
|
Assignee: |
GM Global Technology Operations,
Inc.
Detroit
MI
|
Family ID: |
40363025 |
Appl. No.: |
11/970054 |
Filed: |
January 7, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60956150 |
Aug 16, 2007 |
|
|
|
Current U.S.
Class: |
384/499 ;
29/898.066 |
Current CPC
Class: |
F16C 33/60 20130101;
F16C 33/64 20130101; Y10T 29/49689 20150115 |
Class at
Publication: |
384/499 ;
29/898.066 |
International
Class: |
B21K 1/04 20060101
B21K001/04 |
Claims
1. A method of manufacturing a split bearing race for an angular
contact roller bearing comprising: forming a generally annular
blank having a first annular portion, a second annular portion, and
a third annular portion disposed between said first and second
annular portions; wherein said third annular portion has a
thickness greater than the thickness of said first and second
annular portions; machining at least one of said first, second, and
third annular portions; and forming a first race member and a
second race member of the split bearing race by bifurcating said
generally annular blank along said third annular portion.
2. The method of manufacturing a split bearing race of claim 1,
wherein the split bearing race is an inner bearing race.
3. The method of manufacturing a split bearing race of claim 1,
wherein forming said generally annular blank includes hot
rolling.
4. The method of manufacturing a split bearing race of claim 1,
further comprising heat treating said generally annular blank after
machining at least one of said first, second, and third annular
portions.
5. The method of manufacturing a split bearing race of claim 4,
further comprising finish machining said generally annular blank
subsequent to said heat treating.
6. The method of manufacturing a split bearing race of claim 5,
wherein said finish machining of said generally annular blank
subsequent to said heat treating is performed by grinding.
7. A method of manufacturing a split bearing race for an angular
contact roller bearing comprising: forming a generally annular
blank having a first annular portion, a second annular portion, and
a third annular portion disposed between said first and second
annular portions; wherein said third annular portion has a
thickness greater than the thickness of said first and second
annular portions; wherein forming said generally annular blank
includes hot rolling; machining at least one of said first, second,
and third annular portions; and forming a first race member and a
second race member of the split bearing race by bifurcating said
generally annular blank along said third annular portion.
8. The method of manufacturing a split bearing race of claim 7,
further comprising heat treating said generally annular blank after
machining at least one of said first, second, and third annular
portions.
9. The method of manufacturing a split bearing race of claim 8,
further comprising finish machining said generally annular blank
subsequent to said heat treating.
10. The method of manufacturing a split bearing race of claim 9,
wherein said finish machining of said generally annular blank
subsequent to said heat treating is performed by grinding.
11. A method of manufacturing a split bearing race for an angular
contact roller bearing comprising: forming a generally annular
blank having a first annular portion, a second annular portion, and
a third annular portion disposed between said first and second
annular portions; wherein said third annular portion has a
thickness greater than the thickness of said first and second
annular portions; wherein forming said generally annular blank
includes hot rolling; machining at least one of said first, second,
and third annular portions; heat treating said generally annular
blank after machining at least one of said first, second, and third
annular portions; finish machining said generally annular blank
subsequent to said heat treating by grinding said generally annular
blank; and forming a first race member and a second race member of
the split bearing race by bifurcating said generally annular blank
along said third annular portion.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application 60/956,150, filed Aug. 16, 2007, which is hereby
incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to a method of manufacturing
split bearing races for an angular contact roller bearing.
BACKGROUND OF THE INVENTION
[0003] Angular contact roller bearings include two complements of
roller elements disposed between an inner and an outer bearing
race. The angular contact roller bearing typically employs a split
bearing race for either the inner or outer bearing race. The split
bearing race includes a first race member and a second race member.
The split bearing race facilitates the loading or insertion of the
first and second complement of roller elements during assembly of
the angular contact roller bearing. The dimensional tolerances of
the first and second race members must be maintained to ensure
proper functioning and reliability of the angular contact roller
bearing.
SUMMARY OF THE INVENTION
[0004] A method of manufacturing or forming a split bearing race
for an angular contact roller bearing is provided. The method
includes the steps of: A) forming a generally annular blank having
a first annular portion, a second annular portion, and a third
annular portion disposed between the first and second annular
portions, the third annular portion having a thickness greater than
the thickness of the first and second annular portions; B)
machining at least one of the first, second, and third annular
portions; and C) forming a first and second race member of the
split bearing race by bifurcating the generally annular blank along
the third annular portion. The method may also include the steps
of: D) heat treating the generally annular blank after machining at
least one of the first, second, and third annular portions; and E)
finish machining the generally annular blank subsequent to the heat
treating. In a preferred embodiment, the generally annular blank is
formed by hot rolling.
[0005] The above features and advantages and other features and
advantages of the present invention are readily apparent from the
following detailed description of the best modes for carrying out
the invention when taken in connection with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a cross sectional view of a portion of an angular
contact roller bearing having a split bearing race formed by first
and second race members;
[0007] FIG. 2 is a schematic cross sectional diagram of the first
race member of FIG. 1; and
[0008] FIGS. 3a through 3f are schematic cross sectional
illustrations of hot rolling, machining, heat treating, grinding
and bifurcating a bearing race; taken together, these figures
illustrate a method of manufacturing the first and second bearing
race members of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0009] Referring to the drawings, wherein like reference numbers
correspond to like or similar components throughout the several
views, there is shown in FIG. 1 an angular contact roller bearing,
generally indicated at 10. The angular contact roller bearing 10 is
mounted within a gear member 12, such as a transfer drive gear, and
is retained therein by a retaining ring 14. The angular contact
roller bearing 10 includes an outer bearing race 16 and an inner
bearing race 18. The inner bearing race 18 is characterized as
being a split bearing race; that is, the inner bearing race 18 is
formed by a first race member 20 and a second race member 22. The
inner bearing race 18 defines a bore 24 sufficiently configured to
receive a shaft, not shown, therein. A first plurality of roller
elements 26, one of which is shown in FIG. 1, is disposed between
the outer bearing race 16 and the first race member 20 of the inner
bearing race 18. Similarly, a second plurality of roller elements
28, one of which is shown in FIG. 1, is disposed between the outer
bearing race 16 and the second race member 22 of the inner bearing
race 18. The first and second plurality of roller elements 26 and
28 cooperate with the outer bearing race 16 and the inner bearing
race 18 to provide load support and axial stiffness to the gear
member 12.
[0010] The first and second plurality of roller elements 26 and 28
run or roll on two pairs of convergent angular pathways. The first
and second race members 20 and 22 define first and second outboard
pathways 30 and 32, respectively, while the outer bearing race 16
defines first and second inboard pathways 34 and 36. A first ball
track 38 is the path that the center of each of the first plurality
of roller elements 26 travels within the angular contact roller
bearing 10. Similarly, a second ball track 40 is the path that the
center of each of the second plurality of roller elements 28
travels within the angular contact roller bearing 10. The first
race member 20 includes a primary face 42 and a secondary face 44,
while the second race member 22 includes a primary face 46 and a
secondary face 48. The primary faces 42 and 46 cooperate to provide
the necessary clearances between the first and second plurality of
roller elements 26 and 28, the inner bearing race 18, and the outer
bearing race 16. Therefore, the dimensional tolerances of the
primary faces 42 and 46 must be maintained to ensure the
reliability and proper functioning of the angular contact roller
bearing 10.
[0011] Referring now to FIG. 2, and with continued reference to
FIG. 1, there is shown a schematic view of the first race member 20
of FIG. 1. The distance between the primary face 42 and the first
ball track 38 is indicated as L.sub.1 and the distance between the
secondary face 44 and the first ball track 38 is indicated as
L.sub.2. As described hereinabove, the dimensional tolerances of
distance L.sub.1 must be maintained, while the dimensional
tolerances of the distance L.sub.2, while important, are somewhat
less important than those of distance L.sub.1. Those skilled in the
art will recognize that the dimensional tolerances of the distance
between the second ball track 40 and the primary face 46 of the
second race member 22 should similarly be maintained to ensure
proper functioning to the angular contact roller bearing 10.
[0012] Referring to FIGS. 3a through 3f, and with continued
reference to FIGS. 1 and 2, there is schematically illustrated a
method of forming the first and second race members 20 and 22 of
the inner bearing race 18 of FIG. 1. FIG. 3a illustrates the step
of forming a generally annular blank 50 from a metal such as steel.
In a preferred embodiment, the generally annular blank 50 will be
formed by hot rolling. In the hot rolling process a billet of
metal, not shown, is deformed by a roller 52 while the temperature
of the metal is maintained above its recrystalization temperature.
Since the generally annular blank 50 is formed by hot rolling, a
near-net shape is produced, which reduces the number of subsequent
processing steps and waste created therefrom. The generally annular
blank 50 has a first annular portion 54, a second annular portion
56, and a third annular portion 58 disposed between the first and
second annular portions 54 and 56 and centrally located on the
generally annular blank 50. The first annular portion 54 has a
thickness T.sub.1 and the second annular portion 56 has a thickness
T.sub.2. In a preferred embodiment the thicknesses T.sub.1 and
T.sub.2 are the same, but need not be. The third annular portion 58
has a thickness T.sub.3 which is greater than the thicknesses
T.sub.1 and T.sub.2.
[0013] Referring now to FIGS. 3b and 3c, the generally annular
blank 50 is machined by, without limitation, turning on a lathe or
grinding. Portions 60 are removed from the generally annular blank
50 to form generally annular blank 50A, shown in FIG. 3c. Referring
to FIG. 3c, the generally annular blank 50A is subjected to heat
energy, indicated at 62, and subsequent controlled cooling, such as
by quenching and tempering, to heat treat the generally annular
blank 50A to significantly increase the hardness and wear
resistance thereof During this heat treating operation, the
generally annular blank 50A may distort slightly, and, as such, a
precision machining operation may be required. Referring to FIG.
3d, a grinder 64 (only a portion of which is shown in FIG. 3d) is
employed to machine the generally annular blank 50A subsequent to
the heat treating operation shown in FIG. 3c. The grinder 64 may
have multiple grinding wheels to simultaneously machine various
surfaces, such as the primary faces 42 and 46 and the first and
second outboard pathways 30 and 32, all of FIG. 1. This precision
machining operation provides a highly-toleranced generally annular
blank 50B, shown in FIG. 3e, and establishes the relationship
between the primary face 42 and the first ball track 38 as well as
the relationship between the primary face 46 and the second ball
track 40. Although a grinding operation is illustrated in FIG. 3d,
those skilled in the art will recognize that other precision
machining operations may be employed within the scope of the
claims.
[0014] Referring now to FIG. 3e, there is shown the generally
annular blank 50B. The generally annular blank 50B is parted or
bifurcated along parting line 66, disposed centrally on the
generally annular blank 50B, by a cutting means such as sawing,
turning, etc., to produce the first and second race members 20 and
22 shown in FIG. 3f. Referring now to FIG. 3f, the secondary faces
44 and 48 of the respective first and second race members 20 and 22
are formed at the parting line 66 of FIG. 3e. Consequently, the
precise dimensional tolerances of the primary faces 42 and 46
relative to the respective first and second ball tracks 38 and 40
achieved during the precision machining operation of FIG. 3d are
maintained, and the dimension L2 of FIG. 2 is established. Those
skilled in the art of machining will recognize that the parting
operation, via sawing, turning, etc., is inherently less
dimensionally accurate than the grinding operation described
hereinabove with reference to FIG. 3d.
[0015] Although the method described hereinabove was focused on
forming the inner bearing race 18, the provided method is also an
effective means of producing outer bearing races of the split
bearing race variety. While the best modes for carrying out the
invention have been described in detail, those familiar with the
art to which this invention relates will recognize various
alternative designs and embodiments for practicing the invention
within the scope of the appended claims.
* * * * *