U.S. patent application number 10/953423 was filed with the patent office on 2005-02-17 for one piece stator lead and terminal insulator.
This patent application is currently assigned to Remy International, Inc.. Invention is credited to Edrington, Samuel R..
Application Number | 20050034294 10/953423 |
Document ID | / |
Family ID | 32107453 |
Filed Date | 2005-02-17 |
United States Patent
Application |
20050034294 |
Kind Code |
A1 |
Edrington, Samuel R. |
February 17, 2005 |
One piece stator lead and terminal insulator
Abstract
A method for assembling a one-piece stator lead and terminal
insulator for an oil cooled alternator, wherein the one-piece
stator lead and terminal insulator comprises an arcuate plate
having three cylindrical retainers positioned thereon for receiving
stator terminals. The arcuate plate also includes three guides for
guiding stator leads to the terminals. Three rectangular holes are
provided next to each of the guides. The rectangular holes receive
insulating ties that encircle the stator leads and hold the stator
leads to the plate, properly positioning the stator leads away from
other conductors and housings within the alternator. Two flanges
also extend from the plate to aid in assembly of the device and
further act to properly position the stator leads away from other
conductors and housings within the alternator.
Inventors: |
Edrington, Samuel R.;
(Noblesville, IN) |
Correspondence
Address: |
Thomas A. Walsh
Ice Miller
One American Square
Box 82001
Indianapolis
IN
46282-0200
US
|
Assignee: |
Remy International, Inc.
Anderson
IN
|
Family ID: |
32107453 |
Appl. No.: |
10/953423 |
Filed: |
September 29, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10953423 |
Sep 29, 2004 |
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10282782 |
Oct 29, 2002 |
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6825586 |
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Current U.S.
Class: |
29/596 ; 29/732;
310/261.1 |
Current CPC
Class: |
H02K 5/225 20130101;
Y10T 29/49009 20150115; Y10T 29/53143 20150115; H02K 9/19
20130101 |
Class at
Publication: |
029/596 ;
310/261; 029/732 |
International
Class: |
H02K 001/22 |
Claims
What is claimed is:
1. A method of assembling an alternator having a plurality of leads
and a plurality of terminals, the method comprising the steps of:
a. providing a plate having a plurality of retainers positioned
thereon, each of said plurality of retainers having a bore adapted
to receive one of said plurality of terminals; b. inserting said
plurality of terminals through said bores; and c. securing said
plurality of leads to said plate.
2. The method of claim 1, further comprising the step of: a.
aligning said plurality of leads along guides provided on said
plate.
3. The method of claim 1, further comprising the step of: a.
refraining from placing insulating sleeves on said plurality of
leads.
4. The method of claim 1, further comprising the step of: a.
inserting said plurality of terminals through holes in a rectifier
housing and securing said rectifier housing to a casing.
Description
BACKGROUND
[0001] This invention relates generally to the field of automotive
alternators, and in particular the invention relates to stator
leads and terminal insulators for alternators.
[0002] Typical oil cooled alternators for heavy duty applications
like busses and coaches include a stator having stator windings
positioned about a rotor. The stator windings are encapsulated in
an oil-proof casing that includes a rectifier housing. The stator
includes terminals that extend through the rectifier housing to
provide an electrical connection from the exterior of the rectifier
housing to the windings on the interior of the housing.
[0003] FIG. 1 shows a perspective view of a typical oil cooled
heavy duty alternator 20 having the rectifier housing removed to
expose the stator windings 24. The stator windings 24 include three
distinct windings that make a three-phase winding set, connected in
delta or wye fashion, and positioned on a stator core. The windings
24 may be made of any of several types of windings, including
hairpin-type windings and copper wound windings. Three stator leads
26 are provided in association with the windings 24. The leads 26
carry current from the three-phase windings, and the electric
potential between different leads is measured as the line-to-line
voltage. The leads 26 are typically flexible and comprised of
stranded cable. Accordingly, the term cable leads is also used
herein to refer to the stator leads. Of course, any number of other
conductors could be used for the stator leads, including solid
copper wire or other flexible wire types. Each lead 26 is covered
with a heavy fiberglass insulating sleeve 30. The insulating
sleeves 30 are used to protect the leads 26 from shorting against
other stator conductors should the flexible stator leads
accidentally come into contact with other conductors.
[0004] The cable leads 26 are also connected to the stator
terminals 28, and provide an electric path between the terminals
and the three-phase windings 24. Each terminal is made of a
conductive material such as brass. When a rectifier housing is
placed over the stator, the terminals extend through holes in the
housing to provide a conductive path from the exterior of the
alternator casing 22 to the interior of the alternator casing. Each
terminal 28 is associated with a square insulator 32 positioned at
its base, where the cable lead 26 connects to the terminal. Each
terminal is also associated with a hat-shaped insulator having a
cylindrical portion and a flared round top. This hat shaped
insulator is positioned over on the terminal once the rectifier
housing is placed on the alternator such that the cylindrical
portion seats in the terminal holes of the rectifier housing, and
the flared round top rests against the exterior of the rectifier
housing. These six insulators (two for each terminal) protect the
terminals from inappropriate contact with the rectifier
housing.
[0005] As shown in FIG. 1, before the rectifier housing is place on
the alternator, the terminals 28 are only connected to the cable
leads 26, and the terminals 28 are not otherwise fixed with respect
to the alternator casing 22. Of course, the cable leads 26, are
flexible and do not hold the terminals 28 securely in place. Thus,
before assembly, the terminals 28 move independent with respect to
each other. This independent movement of each terminal 28 can cause
problems during assembly because it is difficult to align the
freely moving terminals 28 with the holes of the rectifier
housing.
[0006] After the alternator is fully assembled and placed in
operation, electric current is generated in the stator windings 24
and delivered to on-board loads. However, the significant electric
currents flowing through the conductors of the alternator can
generates excessive heat during alternator operation. Thus, cooling
oil is provided within the alternator to dissipate the heat. The
cooling oil flows between the alternator conductors, directly
contacting the conductors, and drawing heat away from the
conductors. Still, not all conductors of the alternator come into
direct contact with the cooling oil. In particular, although the
insulating sleeves 30 sufficiently protect the cable leads 26
against shorting during alternator operation, they also block the
cooling oil from directly contacting the cable leads. While some
cooling oil migrates into the sleeves and onto the cable leads,
most of the cooling oil flows around the insulating sleeves and is
prevented from directly contacting the cable leads. Because a
significant amount of cooling oil does not directly contact the
cable leads, they are susceptible to overheating during alternator
operation. Over time, the excessive heat on the cable leads can
break down the conductors and their associated insulation,
resulting in improper current flow and alternator malfunction.
SUMMARY
[0007] A one-piece stator lead and terminal insulator may be used
to assist in alternator assembly and/or assist with alternator
cooling. The insulator comprises an arcuate plate having a
plurality of retainers positioned thereon. Each of the retainers
includes a cylindrical portion that rises above the plate and
includes a bore adapted to receive one of the stator terminals.
When the stator terminals are inserted into the retainer bores, the
terminals are positioned in an upright fashion, and properly spaced
so the rectifier housing may be quickly and easily positioned upon
the alternator with the terminals extending through the rectifier
housing. The plate also includes guides that extend from the plate
in the opposite direction of the retainers. The guides are used to
properly position the cable leads of the alternator against the
plate and direct the leads to the terminals. A plurality of holes
are also positioned upon the plate near the guides. The holes are
dimensioned to receive ties for securing the leads to the plate.
The ties fit through the holes of the plate and encircle the leads,
thereby fastening the leads against the plate. By securing the
leads to the plate, the leads are properly positioned within the
alternator, secured against the insulating plate, and prevented
from inappropriate contact with other conductors within the
alternator. Accordingly, no insulating sleeve is required around
the lead, and cooling oil from the alternator easily flows around
the leads. These and other features, aspects, and advantages of the
present invention will become better understood with reference to
the following description and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 shows a prior art alternator including windings,
insulating sleeves, cable leads, and terminals;
[0009] FIG. 2 shows a top view of a one-piece stator lead and
terminal insulator;
[0010] FIG. 3 shows the bottom view of the one-piece stator lead
and terminal insulator of FIG. 2;
[0011] FIG. 4 shows a perspective view of the one-piece stator lead
and terminal insulator of FIG. 2 positioned within an alternator;
and
[0012] FIG. 5 shows an elevational view of the one-piece stator
lead and terminal insulator of FIG. 2 positioned within an
alternator.
DESCRIPTION
[0013] With reference to FIGS. 2-5, a one-piece stator lead and
terminal insulator 50 comprises an arcuate plate 52 having three
cylindrical retainers 54 positioned thereon for receiving
alternator terminals 28. The arcuate plate 52 also includes three
guides 56 for guiding stator leads 26 to the terminals 28.
Furthermore, three rectangular holes 58 are provided next to each
of the guides 56. The rectangular holes 58 receive plastic ties 66
that encircle the cable leads 26 and hold the leads to the plate
52. Two flanges 60 extend from the plate to aid in assembly of the
device and further act to properly position the cable leads away
from other conductors within the alternator.
[0014] The arcuate plate 52 includes a substantially semi-circular
exterior circumference 53 and a winding interior circumference 51.
The plate 52 is designed to fit in the alternator with its exterior
circumference positioned along the interior circumference of the
casing, similar to the position of the stator core relative to the
interior circumference of the casing. The plate 52 is made of an
electrically insulating material, such as polyphenylene sulfide.
However, any number of other insulating materials may be used.
Furthermore, although the plate is preferably rigid, some flex may
be provided without compromising the function of the plate.
[0015] The three cylindrical retainers 54 are spaced apart from
each other on the plate 52 to align with holes on the rectifier
housing (not shown). The retainers include a cylindrical portion
that extends from the plate a distance that is about the thickness
of the casing cover. Of course, the term cylindrical portion as
used herein may refer to any number of shapes, and is not limited
to a cylinder having a circular cross section. For example, a
cylindrical portion with a rectangular cross section could also be
used. Each retainer 54 is designed to receive one of the terminals
28 of the stator. Thus, each retainer 54 includes a bore 62 that
snugly holds the terminal 28 when the terminal is inserted through
the bore. When the three terminals 28 are all inserted into the
retainers 54 of the insulator 50, they are properly spaced and
positioned for insertion through the holes of the rectifier
housing. When the alternator is assembled, the retainers are seated
in the holes of the rectifier housing, and provide insulation
between the terminals and the housing.
[0016] The three guides 56 extend from the plate in the opposite
direction from the retainers 54. Each guide 56 includes a U-shaped
channel 64 that leads directly to one of the retainer bores 62.
These U-shaped channels are designed to receive one of the cable
leads 26 and properly orient the cable lead for connection to the
terminal 28 extending through the cable bore.
[0017] The three rectangular holes 58 are provided along the
circumference of the plate 52, next to each of the guides 56. As
shown in FIGS. 4 and 5, the holes 58 each receive a tie 66 that is
joined to the plate by inserting the tie through the hole and
wrapping the tie around the cable lead. The ties are fastened at
their ends to form a ring that encircles the cable lead and secures
the cable lead to the plate. The ties are similar in structure to
typical wire harnesses known in the industry for grouping sets of
conductors. The ties are made of flexible insulating material
capable of withstanding high heat. For example, an epoxy
impregnated fiberglass cord may be used to make the ties. The term
tie, as used herein, is meant to encompass any number of devices
used to secure the cable leads to the plate, including, for
example, channels formed in the plate through which the cable leads
are fed.
[0018] The two flanges 60 each include a skirt portion 68 that
extends from the plate 52, and a foot portion 70 that extends from
the skirt in a direction parallel to the plate. The two flanges
serve to insulate the cable leads from rectifier diodes found
within the alternator. The two flanges also assist in positioning
the insulator 50 over the terminals 28 by providing additional
surface area to be held when a robot or human on an assembly line
places the insulator 50 over the terminals.
[0019] During assembly of the alternator, the terminals are
inserted into the retainer bores 62 of the insulator 50. After the
terminals are inserted into the retainer bores 62, the insulator is
positioned in the alternator with the exterior circumference 53 of
the plate 52 aligned just inside the interior circumference of the
alternator casing. Positioning of the insulator 50 within the
alternator facilitates alternator assembly by properly distancing
the terminals 28 from each other and orienting the terminals in an
upright fashion. In particular, because the terminals are all
properly aligned and directed upright, the terminals may be
simultaneously placed into the holes in the rectifier housing and
the rectifier housing may be easily placed directly on the
alternator. Thus, use of the insulator 50 avoids the problem of
terminals moving independent of each other during assembly of the
alternator.
[0020] Also during assembly, ties 66 are used to secure each of the
cable leads to the plate. By securing the cable leads to the
insulator 50, the cable leads are fixed to an insulating member
within the alternator and properly spaced apart from other
conductors within the alternator. This keeps the cable leads secure
and prevents them from shorting by coming into contact with other
conductors or grounding to the housing. Because the cable leads are
separated from other conductors and secured within the alternator,
shorting is not an issue and insulating sleeves do not need to be
included on the cable leads. Accordingly, cooling oil is free to
come in direct contact with the leads during alternator operation,
and overheating of the cable leads is avoided.
[0021] Although the present invention has been described in
considerable detail with reference to certain preferred versions
thereof, other versions are possible. For example, other means than
ties could be used to secure the cable leads to the insulator, such
as channels integrally formed on the plate. As another example, the
retainers need not extend the width of the rectifier housing, but
may be narrow with additional insulators inserted between the
terminal and the rectifier housing. Therefore, the spirit and scope
of the appended claims should not be limited to the description of
the preferred versions contained herein.
* * * * *