U.S. patent application number 16/453183 was filed with the patent office on 2020-12-31 for anti-friction insulated bearing sleeve construction and modularity.
This patent application is currently assigned to ABB Schweiz AG. The applicant listed for this patent is ABB Schweiz AG. Invention is credited to Stephen Douglas Browne, Christopher A. Stockton.
Application Number | 20200408252 16/453183 |
Document ID | / |
Family ID | 1000005272693 |
Filed Date | 2020-12-31 |
United States Patent
Application |
20200408252 |
Kind Code |
A1 |
Stockton; Christopher A. ;
et al. |
December 31, 2020 |
Anti-Friction Insulated Bearing Sleeve Construction and
Modularity
Abstract
An anti-friction insulated bearing system, including a bracket
disposed about a motor driveshaft and a bearing disposed within the
bracket configured to support the driveshaft for rotation. The
system also includes an outer bearing cap disposed proximal a drive
end of the bracket and an inner bearing cap. The system further
includes an insulation sleeve disposed within the bracket proximal
the bearing. The outer bearing cap, the inner bearing cap and the
insulation sleeve are configured as modular components of the
system. The modular insulation sleeve allows the use of standard
anti-friction rolling element bearings. The modular components have
common inner and outer bearing caps that can be used across a
multitude of configurations with a minimal number of parts.
Inventors: |
Stockton; Christopher A.;
(Greenville, SC) ; Browne; Stephen Douglas;
(Shelby, NC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ABB Schweiz AG |
Baden |
|
CH |
|
|
Assignee: |
ABB Schweiz AG
Baden
CH
|
Family ID: |
1000005272693 |
Appl. No.: |
16/453183 |
Filed: |
June 26, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F16C 35/073 20130101;
F16C 2380/26 20130101; F16C 19/525 20130101 |
International
Class: |
F16C 19/52 20060101
F16C019/52; F16C 35/073 20060101 F16C035/073 |
Claims
1. An anti-friction insulated bearing system, comprising: a bracket
disposed about a motor driveshaft; a bearing disposed within the
bracket configured to support the driveshaft for rotation; an outer
bearing cap disposed proximal a drive end of the bracket; an inner
bearing cap; and an insulation sleeve disposed within the bracket
proximal the bearing, wherein the outer bearing cap, the inner
bearing cap and the insulation sleeve are configured as modular
components of the system.
2. The anti-friction insulated bearing system of claim 1, wherein
the inner bearing cap is non-insulated.
3. The anti-friction insulated bearing system of claim 1, further
comprising an insulated shim disposed between the outer bearing cap
and the bracket.
4. The anti-friction insulated bearing system of claim 1, wherein
the insulation sleeve is press fit into the bracket.
5. The anti-friction insulated bearing system of claim 1, wherein
the bracket includes a bracket bore disposed along a central
axis.
6. The anti-friction insulated bearing system of claim 1, further
comprising a seal disposed in the outer bearing cap, wherein the
seal is configured to encircle the motor driveshaft.
7. The anti-friction insulated bearing system of claim 1, wherein
the insulation sleeve includes a sleeve lip extending radially
about a circumference of the insulation sleeve.
8. The anti-friction insulated bearing system of claim 7, wherein
the sleeve lip abuts an outer surface of the bracket.
9. The anti-friction insulated bearing system of claim 1, wherein
the inner bearing cap and the outer bearing cap are configured to
be removably bolted to the bracket.
10. The anti-friction insulated bearing system of claim 1, wherein
the bearing is one of a roller bearing or a ball bearing.
11. The anti-friction insulated bearing system of claim 1, wherein
the insulation sleeve is impregnated with a synthetic resin as
insulation.
12. The anti-friction insulated bearing system of claim 7, wherein
the outer bearing cap is circumferentially larger than the
circumference of the insulation sleeve.
13. The anti-friction insulated bearing system of claim 1, wherein
the insulation sleeve includes a non-electrical conductive
polymer.
14. An anti-friction insulated bearing system, comprising: a
bracket disposed about a motor driveshaft; a bearing disposed
within the bracket configured to support the driveshaft for
rotation; an outer bearing cap disposed proximal a drive end of the
bracket; an inner bearing cap; and an insulation sleeve disposed
within the bracket proximal the bearing, wherein the outer bearing
cap, the inner bearing cap and the insulation sleeve are configured
as modular components of the system; and wherein the inner bearing
cap and the outer bearing cap are arranged and configured to
matingly engage with a plurality of different types of insulation
sleeves when any one of the plurality of different types of
insulation sleeves is installed in the anti-friction insulated
bearing system to replace the insulation sleeve.
15. (canceled)
16. A motor bracket, comprising: a bearing disposed within the
bracket configured to support a driveshaft for rotation; an outer
bearing cap disposed proximal a drive end of the bracket; an inner
bearing cap; and an insulation sleeve disposed within the bracket
proximal the bearing, wherein the outer bearing cap, the inner
bearing cap and the insulation sleeve are configured as modular
components.
17. (canceled)
18. The motor bracket of claim 16, wherein the inner bearing cap
and the outer bearing cap are arranged and configured to matingly
engage with a plurality of different types of insulation sleeves
when any one of the plurality of different types of insulation
sleeves is installed in the motor bracket to replace the insulation
sleeve.
19. The motor bracket of claim 16, wherein the insulation sleeve
includes a non-electrical conductive polymer.
20. The motor bracket of claim 16, wherein the outer bearing cap is
circumferentially larger than the circumference of the insulation
sleeve.
Description
BACKGROUND OF THE INVENTION
[0001] Stock motors can be modified to meet specific requirements.
Therefore, some components are stocked in order to expedite any
requested modifications. Referring now to FIGS. 1 and 2, there is a
flowchart 10 illustrating an end bracket assembly 12, where the
drive end standard non-insulated bracket can be modified to be
insulated, and alternate seals can be selected on both ends.
Previous designs consist of a bracket 22 (non-insulated 14 or
insulated 16), inner cap 30 and bearing 28. A seal 24 is mounted to
the shaft 31 and located within a machined cavity on the bracket
22. The bracket cavity is machined differently for each seal. Five
(5) or more seal options are needed. Bracket 22 has to be machined
and stocked to accommodate a modification request by a user. In
most conventional designs, two main problems exist with these two
modifications: 1.) When a user or customer modifies a stock motor
from a non-insulated bracket 14 to an insulated bracket 16, in each
bracket 14, 16 the inner cap 30 is replaced with a different inner
cap. As a result, the bearing is removed, which damages the
bearing, and is subsequently scrapped. In addition to this,
different brackets are used when the bearing is non-insulated or
insulated. As shown in FIG. 1, there is a minimum of eight (8)
brackets have to be stocked for each bearing size to accommodate
this. In other words, four shaft seals (18b, 18c, 18d, 18e)
multiplied by two insulation methods (14, 16) results in eight
brackets (19b, 19c, 19d, 19e) per method (14, 16) which may be
rather expensive; and 2.) A feature is machined in the bracket for
the shaft seal (18a, 19a). Since the geometry of each seal is
different from the other, for each bearing size, at least four (4)
different brackets are stocked in order to meet the user's choice
of shaft seal which can also be very expensive and cause long lead
times to produce as a non-standard part. Bearing that have
insulation on the outer diameter and side are costly to
produce.
[0002] Typical electric machine bearings have a need to be
insulated against circulating currents induced in the rotor. These
currents, called shaft currents, pass through the machine's shaft
and bearing and damage the bearings. Electric machines use hybrid
ceramic element bearings, ceramic-coated bearings and composite
sleeves to prevent these circulating currents. Ceramic bearings and
composite sleeves are expensive and difficult to procure in a wide
variety of sizes.
[0003] Referring now to FIG. 2, there is a conventional bearing
insulation system 20 which includes a driveshaft 31, a bracket 22
disposed about the driveshaft 31, a seal 24 disposed within the
bracket 22, an insulation sleeve 26 pressed into bracket 22, an
insulated bearing 28 disposed in bracket 22, and an inner cap 30
isolated from a bearing 28 by an insulated spacer 32. This system
20 has all of the disadvantages and problems discussed above when
modification are required by a user. Thus, there is a need to
provide a less expensive and more readily available bearing
insulation system as the present invention addresses herein.
BRIEF SUMMARY OF THE INVENTION
[0004] The invention provides an anti-friction insulated bearing
system, including a bracket disposed about a motor driveshaft and a
bearing disposed within the bracket configured to support the
driveshaft for rotation. The system also includes an outer bearing
cap disposed proximal a drive end of the bracket and an inner
bearing cap. The system further includes an insulation sleeve
disposed within the bracket proximal the bearing. The outer bearing
cap, the inner bearing cap and the insulation sleeve are configured
as modular components of the system.
[0005] The invention provides a motor bracket including a bearing
disposed within the bracket configured to support a driveshaft for
rotation and an outer bearing cap disposed proximal a drive end of
the bracket. The bracket also includes an inner bearing cap and an
insulation sleeve disposed within the bracket proximal the bearing.
The outer bearing cap, the inner bearing cap and the insulation
sleeve are configured as modular components.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0006] FIG. 1 is a flowchart illustrating a conventional end
bracket bearing assembly.
[0007] FIG. 2 is a diagrammatic cross-sectional view of a
conventional bearing insulation system.
[0008] FIG. 3 is a flowchart illustrating an end bracket bearing
assembly according to an embodiment.
[0009] FIG. 4 is a diagrammatic cross-sectional view of bearing
insulation system according to an embodiment.
[0010] FIG. 5A is a schematic plan view illustrating a bearing
insulation system (w/o sleeve) according to an embodiment.
[0011] FIG. 5B is a schematic cross-sectional view taken along A-A
of FIG. 5A.
[0012] FIG. 5C is a schematic plan view illustrating a bearing
insulation system (w/sleeve) according to an embodiment.
[0013] FIG. 5D is a schematic cross-sectional view taken along A-A
of FIG. 5C.
[0014] FIG. 6A is a schematic plan view of an outer bearing cap of
a bearing insulation system according to an embodiment.
[0015] FIG. 6B is a schematic cross-sectional view taken along A-A
of FIG. 6A.
[0016] FIG. 6C is a schematic cross-sectional view taken along B-B
of FIG. 6A.
[0017] FIG. 7A is a schematic plan view of an inner bearing cap of
a bearing insulation system according to an embodiment.
[0018] FIG. 7B is a schematic cross-sectional view taken alone A-A
of FIG. 7A.
[0019] FIG. 7C is a schematic cross-sectional view taken alone B-B
of FIG. 7A.
[0020] FIG. 8A is a schematic plan view of a bracket of a bearing
insulation system according to an embodiment.
[0021] FIG. 8B is a schematic cross-sectional view taken alone A-A
of FIG. 8A.
[0022] FIG. 8C is a schematic cross-sectional view taken alone B-B
of FIG. 8A.
[0023] FIG. 8D is a schematic cross-sectional view taken alone D-D
of FIG. 7A.
[0024] FIG. 8E is a schematic detailed view taken at C of FIG.
7A.
[0025] FIG. 9A is a schematic plan view of an insulation sleeve of
a bearing insulation system according to an embodiment.
[0026] FIG. 9B is a schematic cross-sectional view taken along B-B
of FIG. 9A.
[0027] FIG. 9C is a schematic detailed view taken at C of FIG.
9B.
[0028] FIG. 10 is a schematic plan view of an outer cap insulation
shim of a bearing insulation system according to an embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0029] All references, including publications, patent applications,
and patents, cited herein are hereby incorporated by reference to
the same extent as if each reference were individually and
specifically indicated to be incorporated by reference and were set
forth in its entirety herein.
[0030] The use of the terms "a" and "an" and "the" and "at least
one" and similar referents in the context of describing the
invention (especially in the context of the following claims) are
to be construed to cover both the singular and the plural, unless
otherwise indicated herein or clearly contradicted by context. The
use of the term "at least one" followed by a list of one or more
items (for example, "at least one of A and B") is to be construed
to mean one item selected from the listed items (A or B) or any
combination of two or more of the listed items (A and B), unless
otherwise indicated herein or clearly contradicted by context. The
terms "comprising," "having," "including," and "containing" are to
be construed as open-ended terms (i.e., meaning "including, but not
limited to,") unless otherwise noted. Recitation of ranges of
values herein are merely intended to serve as a shorthand method of
referring individually to each separate value falling within the
range, unless otherwise indicated herein, and each separate value
is incorporated into the specification as if it were individually
recited herein. All methods described herein can be performed in
any suitable order unless otherwise indicated herein or otherwise
clearly contradicted by context. The use of any and all examples,
or exemplary language (e.g., "such as") provided herein, is
intended merely to better illuminate the invention and does not
pose a limitation on the scope of the invention unless otherwise
claimed. No language in the specification should be construed as
indicating any non-claimed element as essential to the practice of
the invention.
[0031] Referring now to FIG. 3, there is a flowchart 40
illustrating an end bracket bearing assembly 42 which includes a
non-insulated inner cap machining step 44 and a bracket machining
step 46. These steps may lead to a shaft seal 48a step and a shaft
seal outer cap 50a step. In certain embodiments, shaft seal 48a
step, depending on a user's requirements for the end bracket, may
include a plurality of shaft seal options (48b, 48c, 48d, 48e)
corresponding to a matching plurality of shaft seal outer cap
options (50b, 50c, 50d, 50e) which may each be machined, as
needed.
[0032] Referring now to FIG. 4, there is a bearing insulation
system 60 including a bracket 62, an insulated shim 64, an
insulation sleeve 66, an outer bearing cap 68, an inner bearing cap
70, a driveshaft 71 and a bearing 72. In certain embodiments, shim
64 is disposed between the outer bearing cap 68 and the bracket 62.
Also, sleeve 66 may be press fit into bracket 62. Inner bearing cap
70 may be utilized for either an insulated or non-insulated
assembly. Bearing 72 may be a roller or ball type for example.
[0033] In certain embodiments, electric machine bracket assemblies
are configured for modular configurations by having a minimum
number of machined brackets/endplates 62, inner bearing caps 70 and
outer bearing caps 68. The modular components have common outer and
inner bearing caps 68, 70, respectively, that may be used across a
multitude of configurations with a minimal number of parts to be
machined. For example, a modular insulation sleeve 66 allows for
the use of standard anti-friction rolling element bearings. Seal 78
such as provisions for slingers, lip seals and the like are
provided through a change in the outer bearing cap 68 only as
opposed to being combined in the bracket 62. Isolation of the
bearing may be accomplished by using an insulation sleeve 66 that
is retained in the bracket 62 via bolts 63. The insulation sleeve
66 may be sized such that the inner bearing cap 70 does not need to
be isolated from the bracket 62.
[0034] In some embodiments, bracket 62 manufacture includes a cast
or insulation sleeve 66 which is machined and wrapped in an
insulating material which is then impregnated with a synthetic
resin material. Insulation on the sleeve 66 is then machined to
size and placed into a bore 81 of the bracket 62. The outer bearing
cap 68 and inner bearing cap 70 are assembled on a motor as shown
in FIG. 4. Note that outer bearing cap 68 is larger than sleeve 66,
this is done to prevent axial movement of the sleeve due to
possibility of impact to the driveshaft 71 on either end of motor
(not shown). Alternative materials may be used to make the
insulation sleeves 66. Any non-electrical conductive material that
is dense enough to carry the weight and withstand the temperature
may be used. Some polymer and ceramic material may be viable
alternatives to a cast iron wrapped sleeve.
[0035] The bearing insulation system 60 may be utilized on a number
of motors, such as, rib-cooled induction, modular induction,
synchronous, variable speed, AboveNEMA, severe duty, and general
purpose motors, or the like.
[0036] In some embodiments the bracket 62 utilizes one inner
bearing cap 70 for insulated and non-insulated bearings 72. Fewer
parts are stocked because of this. When the user modifies the stock
motor to have an insulated drive end (DE) bearing, the bearing is
not removed, and subsequently is not scrapped. Two bracket options
exist, one non-insulated and one insulated. The stock motor comes
with a non-insulated DE bracket; only one insulated bracket per
bearing size is kept in stock to accommodate customer
modifications. For the conventional system design, eight (8) total
brackets are stocked.
[0037] In certain embodiments, the bracket 62 is no longer machined
for various shaft seals. The bracket 62 has been configured to
accommodate an outer bearing cap 68, which is machined to fit the
seal 78. The outer bearing cap 68 is smaller, cheaper and easier to
machine. When a user modifies a stock order and chooses an
alternate shaft seal, only the outer bearing cap 68 is removed and
replaced; the bracket 62 remains unchanged. At least four (4) outer
caps have to be stocked, but they are smaller and cheaper than
large brackets.
[0038] Referring now to FIGS. 5A to 5D, there is a bearing
insulation system 60 including bracket 62 and outer bearing cap 68
mounted via bolts 63 to the bracket 62. In some embodiments, outer
bearing cap 68 includes an opening 74 configured to pass-through
driveshaft 71 when assembled. In FIG. 5B there is a cross-section
of system 60 taken along A-A of FIG. 5A including bracket 62 having
a bore 81 wherein insulation sleeve 66 may be press fit. Sleeve 66
includes a sleeve opening 80 wherein bearing 72 is disposed. In
certain embodiments, outer bearing cap 68, inner bearing cap 70 and
bearing 72 include co-axial openings at 74 in which driveshaft 71
rotates therein. In FIG. 5C, opening 74 further includes an opening
lip 76 in which seal 78 may be disposed in a tight fit. FIG. 5D is
a cross-sectional view of system 60 taken along A-A of FIG. 5C
illustrating seal 78 disposed within lip 76.
[0039] Referring now to FIG. 6A, there is an outer bearing cap 68
of a bearing insulation system 60 according to an embodiment. In
some embodiments, outer bearing cap 68 includes opening 74 and lip
76 disposed about opening 74. In FIG. 6B there is a cross-sectional
view of outer bearing cap 68 taken along A-A of FIG. 6A. In FIG. 6C
there is a cross-sectional view of outer bearing cap 68 taken along
B-B of FIG. 6A showing machined features of outer bearing cap
68.
[0040] Referring now to FIG. 7A, there is an inner bearing cap 70
of a bearing insulation system 60 according to an embodiment. In
certain embodiments, inner bearing cap 70 includes an opening 75
which corresponds to opening 74 upon assembly of system 60. In FIG.
7B there is a cross-sectional view of inner bearing cap 70 taken
alone A-A of FIG. 7A showing opening 75. In FIG. 7C there is a
cross-sectional view of inner bearing cap 70 taken alone B-B of
FIG. 7A.
[0041] Referring now to FIG. 8A, there is a bracket 62 of a bearing
insulation system 60 including the insulation sleeve 66 disposed
within bracket bore 81 via a press fit or the like. Sleeve 66
includes sleeve opening 80 configured to fit bearing 72 therein. In
FIG. 8B there is a cross-sectional view of bracket 62 taken alone
A-A of FIG. 8A showing sleeve opening 80 and insulation sleeve 66
disposed within bore 81 of bracket 62. In FIG. 8C there is a
cross-sectional view of bracket 62 taken alone B-B of FIG. 8A
illustrating a top portion of sleeve 66 disposed in bore 81. In
FIG. 8D is a cross-sectional view of bracket 62 taken alone D-D of
FIG. 7A shows a connector bore configured to bolt bracket 62 to a
motor (not shown). In FIG. 8E there is a detailed view of the press
fit contact between bracket 62 and insulation sleeve 66 taken at C
of FIG. 7A.
[0042] Referring now to FIGS. 9A and 9B, there is an insulation
sleeve 66 of a bearing insulation system 60 according to an
embodiment. Insulation sleeve 66 includes a sleeve lip 82 and a
sleeve opening 80. Sleeve 66 as discussed above may be press fit
into bore 81 of bracket 62 upon assembly. In FIG. 9B there is a
cross-sectional view of sleeve 66 taken along B-B of FIG. 9A. In
FIG. 9C there is a detailed view of the sleeve lip 82 taken at C of
FIG. 9B. In some embodiments, lip 82 abuts a surface of bracket 62
proximal inner bearing cap 70 upon assembly of system 60. As
discussed above, in certain embodiments, insulation sleeve 66 may
be machined and wrapped in an insulating material which may then be
impregnated with a synthetic resin material. Insulation on the
sleeve 66 is then machined to size and placed into a bore 81 of the
bracket 62
[0043] Referring now to FIG. 10, there is an outer cap insulation
shim 64 of a bearing insulation system 60 according to an
embodiment. Shim 64 may be disposed between the outer bearing cap
68 and the bracket 62 for electrical isolation purposes. Shim 64
may include a shim opening 84 configured to fit about the outer
ring 86 of outer bearing cap 68 with shim 64 sandwiched between
bracket 62 and outer bearing cap 68 upon assembly.
[0044] As will be apparent to one of ordinary skill in the art from
a reading of this disclosure, the present disclosure can be
embodied in forms other than those specifically disclosed above.
The particular embodiments described above are, therefore, to be
considered as illustrative and not restrictive. Those skilled in
the art will recognize, or be able to ascertain, using no more than
routine experimentation, numerous equivalents to the specific
embodiments described herein. Thus, it will be appreciated that the
scope of the present invention is not limited to the above
described embodiments, but rather is defined by the appended
claims; and that these claims will encompass modifications of and
improvements to what has been described.
[0045] Preferred embodiments of this invention are described
herein, including the best mode known to the inventors for carrying
out the invention. Variations of those preferred embodiments may
become apparent to those of ordinary skill in the art upon reading
the foregoing description. The inventors expect skilled artisans to
employ such variations as appropriate, and the inventors intend for
the invention to be practiced otherwise than as specifically
described herein. Accordingly, this invention includes all
modifications and equivalents of the subject matter recited in the
claims appended hereto as permitted by applicable law. Moreover,
any combination of the above-described elements in all possible
variations thereof is encompassed by the invention unless otherwise
indicated herein or otherwise clearly contradicted by context.
* * * * *