U.S. patent application number 15/432200 was filed with the patent office on 2017-06-01 for electric motor brush apparatus and method.
The applicant listed for this patent is The Scott Fetzer Company. Invention is credited to Daniel K. Amonett.
Application Number | 20170155300 15/432200 |
Document ID | / |
Family ID | 54355911 |
Filed Date | 2017-06-01 |
United States Patent
Application |
20170155300 |
Kind Code |
A1 |
Amonett; Daniel K. |
June 1, 2017 |
ELECTRIC MOTOR BRUSH APPARATUS AND METHOD
Abstract
A motor assembly includes: a motor housing including: at least
one brush receptacle having top and bottom ends; a locking element
extending from the top end toward the bottom end; and a housing
spring member; at least one brush holder apparatus including: a
brush holder housing sized to be received within the brush
receptacle, including: an upper surface and a lower surface; a
receiving aperture; and an open end; a brush spring enclosed by the
brush holder housing; and a brush located inside the brush holder
housing; wherein the brush holder apparatus is inserted inside the
brush receptacle; and wherein the housing spring member urges the
brush holder apparatus toward the top end such that the locking
element is received inside the receiving aperture.
Inventors: |
Amonett; Daniel K.;
(Murfreesboro, TN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
The Scott Fetzer Company |
Westlake |
OH |
US |
|
|
Family ID: |
54355911 |
Appl. No.: |
15/432200 |
Filed: |
February 14, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14325602 |
Jul 8, 2014 |
9601967 |
|
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15432200 |
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61987831 |
May 2, 2014 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H02K 13/00 20130101;
Y10T 29/49011 20150115; H02K 5/145 20130101; H02K 13/10 20130101;
H01R 39/04 20130101; H02K 23/08 20130101; H02K 13/006 20130101;
H01R 39/381 20130101; H01R 39/40 20130101; H02K 5/148 20130101;
H02K 5/225 20130101 |
International
Class: |
H02K 5/14 20060101
H02K005/14; H01R 39/40 20060101 H01R039/40; H01R 39/38 20060101
H01R039/38; H02K 13/10 20060101 H02K013/10; H02K 5/22 20060101
H02K005/22 |
Claims
1. A motor assembly comprising: a motor housing comprising: at
least one brush receptacle extending along a longitudinal axis of
the brush receptacle and having a top end and a bottom end that are
substantially parallel to the longitudinal axis; a locking element
extending from the top end toward the bottom end of each brush
receptacle; and a cantilevered housing spring member having a
distal end extending substantially along the longitudinal axis and
extending from the bottom end toward the top end of each brush
receptacle; and at least one brush holder apparatus comprising: a
brush holder housing sized to be received within the at least one
brush receptacle, comprising: an upper surface and a lower surface
that are substantially parallel; a first receiving aperture in the
upper surface configured to receive the locking element when the
brush holder housing is inserted inside the at least one brush
receptacle; and an open end that is substantially perpendicular to
the upper surface; a brush spring enclosed by the brush holder
housing; and a brush located inside the brush holder housing but
urged out of the open end of the brush holder housing by the brush
spring along the longitudinal axis when the brush holder housing is
inserted inside the at least one brush receptacle; wherein the at
least one brush holder apparatus is inserted inside the at least
one brush receptacle along the longitudinal axis; and wherein the
housing spring member urges the at least one brush holder apparatus
toward the top end of the at least one brush receptacle such that
the locking element is received inside the first receiving
aperture.
2. A method comprising the steps of: a) providing: a motor housing
comprising: at least one brush receptacle extending along a
longitudinal axis of the brush receptacle and having a top end and
a bottom end that are substantially parallel to the longitudinal
axis; a locking element extending from the top end toward the
bottom end of each brush receptacle; and a cantilevered housing
spring member having a distal end extending substantially along the
longitudinal axis and extending from the bottom end toward the top
end of each brush receptacle; and at least one brush holder
apparatus comprising: a brush holder housing sized to be received
within the at least one brush receptacle, comprising: an upper
surface and a lower surface that are substantially parallel; a
first receiving aperture in the upper surface configured to receive
the locking element when the brush holder housing is inserted
inside the at least one brush receptacle; and an open end that is
substantially perpendicular to the upper surface; a brush spring
enclosed by the brush holder housing; and a brush located inside
the brush holder housing but urged out of the open end of the brush
holder housing by the brush spring along the longitudinal axis when
the brush holder housing is inserted inside the at least one brush
receptacle; b) inserting the at least one brush holder apparatus,
the open end first, into the at least one brush receptacle along
the longitudinal axis, causing the housing spring member to move
away from the top end of the brush receptacle; c) aligning the
locking element with the first receiving aperture; and d) allowing
the housing spring member to urge the brush holder apparatus toward
the top end of the brush receptacle and causing the first receiving
apparatus to receive the locking element.
Description
I. BACKGROUND
[0001] This invention pertains to the art of installing motor brush
holders inside a motor. It is known in the art to secure a brush
housing apparatus to an electric motor housing by using an
interference fit between the outside surface of the brush housing
and a receiving surface on the motor housing. The brush housing may
be further secured by applying adhesive to the assembled parts.
This method of attachment may be expensive as the interference fit
requires exacting tolerances to both mating parts. These tolerances
can add cost to the assembly. Also the choice of adhesive may be
difficult as the brush operates in a high temperature and high
vibration environment.
[0002] It is also known in the art to use straps and fasteners to
secure the brush to the motor housing. This method adds additional
parts and additional assembly time to the motor. Another known
securing method is to add tabs to the outside of the brush
apparatus and locate the brush in a receptacle formed in the motor
housing. The brush is then secured in the housing by bending the
tabs over the receptacle. Bending the tabs according to this method
adds assembly time and thus cost.
[0003] One known method to electrically connect the brush apparatus
to the motor field is to extend a conductive wire from the brush
and electrically connect the wire to a wire extending from the
motor field. This method adds additional assemble steps and time to
the electric motor assembly.
[0004] What is needed is a durable, efficient, simplified, and
cost-effective method and apparatus to electrically connect and
secure brush apparatuses and field windings of electric motors
without using adhesives, fasteners, or wire splices.
II. SUMMARY
[0005] In accordance with one aspect of the present invention, a
motor assembly includes: a motor housing including: at least one
brush receptacle extending along a longitudinal axis of the brush
receptacle and having a top end and a bottom end that are
substantially parallel to the longitudinal axis; a locking element
extending from the top end toward the bottom end of each brush
receptacle; and a cantilevered housing spring member having a
distal end extending substantially along the longitudinal axis and
extending from the bottom end toward the top end of each brush
receptacle; at least one brush holder apparatus including: a brush
holder housing sized to be received within the at least one brush
receptacle, including: an upper surface and a lower surface that
are substantially parallel; a first receiving aperture in the upper
surface configured to receive the locking element when the brush
holder housing is inserted inside the at least one brush
receptacle; and an open end that is substantially perpendicular to
the upper surface; a brush spring enclosed by the brush holder
housing; and a brush located inside the brush holder housing but
urged out of the open end of the brush holder housing by the brush
spring along the longitudinal axis when the brush holder housing is
inserted inside the at least one brush receptacle; wherein the at
least one brush holder apparatus is inserted inside the at least
one brush receptacle along the longitudinal axis; and wherein the
housing spring member urges the at least one brush holder apparatus
toward the top end of the at least one brush receptacle such that
the locking element is received inside the first receiving
aperture.
[0006] In accordance with another aspect of the present invention,
a motor assembly includes: a field including: a laminated stator;
at least one terminal block secured to the laminated stator and
including a connector receptacle; field windings; and at least one
wire electrically connected to the field windings and positioned
partly in the connector receptacle; at least one conductive
connector including: two substantially flat and parallel
displacement members, each including: a top portion; and a distal
portion including a cutting portion extending from the distal
portion toward the top portion and configured to receive the wire;
and two connector spring members, each including: a substantially
flat lower portion adjacent to, connected to, and substantially
perpendicular to at least one displacement member; and an upper
portion extending above the top portions of the displacement
members and cantilevered along substantially a connector axis of
the connector; wherein the cutting portions of the displacement
members align along the connector axis, and wherein the
displacement members are substantially perpendicular to the
connector axis; wherein the top portions of the displacement
members define a brush receiving plane; wherein the distal portions
of the displacement members extend below the lower portions of the
connector spring members; and wherein the upper portions of the
connector spring members are angled toward each other at
cantilevered ends, defining with the brush receiving plane a brush
receiving channel along the connector axis, wherein the brush
receiving channel narrows in the direction of the connector axis
toward the cantilevered ends; and at least one brush holder
apparatus including: a brush holder housing sized to be received
within the brush receiving channel, comprising an open end; a brush
spring enclosed by the brush holder housing; and a brush located
inside the brush holder housing but urged out of the open end of
the brush holder housing by the brush spring along the connector
axis when the brush holder housing is inserted inside the brush
receiving channel; wherein the at least one connector is inserted
into the connector receptacle such that the cutting portions of the
displacement members receive and make electrical connection with
the at least one wire; and wherein the at least one brush holder
apparatus is inserted inside the brush receiving channel of the at
least one connector along the connector axis in the direction of
narrowing of the brush receiving channel until the at least one
brush holder apparatus is held securely by the at least one
connector.
[0007] In accordance with still another aspect of the present
invention, a method includes the steps of: a) providing: a motor
housing including: at least one brush receptacle extending along a
longitudinal axis of the brush receptacle and having a top end and
a bottom end that are substantially parallel to the longitudinal
axis; a locking element extending from the top end toward the
bottom end of each brush receptacle; and a cantilevered housing
spring member having a distal end extending substantially along the
longitudinal axis and extending from the bottom end toward the top
end of each brush receptacle; at least one brush holder apparatus
including: a brush holder housing sized to be received within the
at least one brush receptacle, including: an upper surface and a
lower surface that are substantially parallel; a first receiving
aperture in the upper surface configured to receive the locking
element when the brush holder housing is inserted inside the at
least one brush receptacle; and an open end that is substantially
perpendicular to the upper surface; a brush spring enclosed by the
brush holder housing; and a brush located inside the brush holder
housing but urged out of the open end of the brush holder housing
by the brush spring along the longitudinal axis when the brush
holder housing is inserted inside the at least one brush
receptacle; b) inserting the at least one brush holder apparatus,
the open end first, into the at least one brush receptacle along
the longitudinal axis, causing the housing spring member to move
away from the top end of the brush receptacle; c) aligning the
locking element with the first receiving aperture; and d) allowing
the housing spring member to urge the brush holder apparatus toward
the top end of the brush receptacle and causing the first receiving
apparatus to receive the locking element.
[0008] Still other benefits and advantages of the invention will
become apparent to those skilled in the art to which it pertains
upon a reading and understanding of the following detailed
specification.
III. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The invention may take physical form in certain parts and
arrangement of parts, embodiments of which will be described in
detail in this specification and illustrated in the accompanying
drawings which form a part hereof and wherein:
[0010] FIG. 1 is a perspective view of an assembled motor.
[0011] FIG. 2 is a perspective view of a disassembled motor.
[0012] FIG. 3 is a cross-sectional perspective view of a brush
holder apparatus installed in a motor housing.
[0013] FIG. 4 is a perspective view of an insulation displacement
connector.
[0014] FIG. 5 is a perspective view of an insulation displacement
connector installed in a terminal board.
[0015] FIG. 6 is a perspective view of an insulation displacement
connector contacting a brush holder apparatus.
[0016] FIG. 7 is a view of a flat sheet cut out in the shape of an
insulation displacement connector.
[0017] FIG. 8 is a bottom view of an insulation displacement
connector.
[0018] FIG. 9 is an end view of a motor.
IV. DETAILED DESCRIPTION
[0019] Referring now to the drawings wherein the showings are for
purposes of illustrating embodiments of the invention only and not
for purposes of limiting the same, and wherein like reference
numerals are understood to refer to like components, FIG. 1 shows
an assembled electric motor 2. The motor 2 may have a motor housing
20 that receives and secures at least one brush holder apparatus
10. In one embodiment, the motor housing 20 may be made from
electrically insulating materials; a non-limiting example of such a
material would be plastic or polymer. In another embodiment, the
housing 20 may be made from a conductive material. Motors 2 may
include any DC, AC, or universal motors that use brushes. Such
motors may be used in applications that include, but are not
limited to, blenders, vacuum cleaners, air compressors, and other
devices.
[0020] FIG. 2 shows a perspective view of a disassembled motor 2.
The motor may further include an armature 3, which has a commutator
4, and a field 5. The armature 3 may be inserted along a motor axis
26 (aligned with the motor shaft) inside the field 5 and both 3, 5
placed inside the motor housing 20 such that at least a portion of
the field 5 is housed inside the housing 20, as shown in FIG. 1. If
the motor housing 20 is made from a conductive material, insulation
may isolate the housing 20 from the armature 3, the field 5, and
the brush holder apparatus 10.
[0021] With continued reference to FIG. 2, one embodiment of the
motor 2 may include two brush holder apparatuses 10. In another
embodiment, the two brush holder apparatuses 10 may be positioned
within the motor housing 20 opposite each other, aligned along a
common axis 7. In another embodiment, the two brush holder
apparatuses 10 may be offset from a common axis 7 within the motor
housing 20; FIG. 9 shows such an example. In another embodiment,
the offset brush holder apparatuses 10 may be parallel to each
other. In alternative embodiments, as many brush holder apparatuses
10 as needed may be used. In another embodiment, the brush holder
apparatuses 10 may be positioned at corners of a substantially
rectangular housing 20. The brush holder apparatus 10 may include a
brush holder housing 9 and a brush 8. In one embodiment, the brush
8 may be made from carbon. In one embodiment, the brush holder
housing 9 may be made from a conductive material, including, but
not limited to, brass, copper, silver, gold, and aluminum. In
alternative embodiments, the brush holder housing 9 may be made
from a nonconductive material, including, but not limited to,
polymer and rubber.
[0022] With continued reference to FIG. 2, the motor housing 20 may
include at least one brush receptacle 24 sized to receive the at
least one brush holder apparatus 10. In alternative embodiments,
the housing 20 may include as many brush receptacles 24 as there
are brush holder apparatuses 10. The brush holder apparatus 10 may
be inserted into the brush receptacle 24 from outside the housing
20 inwards along the apparatus's (or the brush receptacle's 24)
longitudinal axis 7 and perpendicular to the motor axis 26. The
armature 3 and field 5 may be secured inside the housing 20 such
that the field 5 encircles and matches the armature 3 and the brush
holder apparatus 10, when installed inside the brush receptacle 24,
is aligned such that the brush 8 contacts the commutator 4.
[0023] FIG. 3 shows a partial cross-sectional view of a brush
holder apparatus 10 installed in a brush receptacle 24 of the motor
housing 20. While it is known in the art to secure a brush holder
to a motor housing, what is not known is how to achieve a secure
attachment by integrating the securing features into the housing 20
and the brush holder apparatus 10, thus eliminating fasteners,
adhesives, and additional assembly steps. A brush holder apparatus
10 may take the form of a substantially four-sided brush holder
housing 9 extended along a longitudinal axis 7 of the brush holder
apparatus 10. In alternative embodiments, the brush holder housing
9 may be a rectangular prism, or may have some rounded sides, as
shown in FIG. 6. A brush spring 6 may be secured inside the brush
holder housing 9 to urge the brush 8 out of an open end of the
brush holder housing 9 such that the brush 8 may contact the
commutator 4 when the motor 2 is assembled. The brush holder
apparatus 10 may have receiving apertures 11 formed on its upper
and lower surfaces. These receiving apertures 11 may have locating
elements 12 substantially adjacent to the location of the apertures
11. The locating elements 12 may extend above the upper and lower
surfaces of the brush holder apparatus 10 away from the lower and
upper surfaces, respectively. In another embodiment, the brush
holder apparatus 10 may have only one receiving aperture 11 and
locating element 12.
[0024] With continued reference to FIG. 3, extending down from the
top interior surface or end of the brush receptacle 24 toward its
bottom end may be a locking element 21. The description of a top or
bottom end or surface is an arbitrary reference point, and such
surfaces or ends may be oriented in any other direction or angle.
The position, size, and shape of the locking element 21 may be such
that when the brush holder apparatus 10 is put into the brush
receptacle 24, the locking element 21 is received inside the
receiving aperture 11. Formed into the brush receptacle 24 and
located adjacent to the locking element 21 may be a recessed pocket
22. The recessed pocket 22 provides clearance for the locating
element 12 so that the brush holder apparatus 10 may be inserted
into the brush receptacle 24 without interference. A surface 25
common to the recessed pocket 22 and the locking element 21 may
cooperate with the locating element 12 to locate the brush holder
apparatus 10 along the longitudinal axis 7.
[0025] With continued reference to FIG. 3, also contained within
the brush receptacle 24 may be a housing spring member 23 or
spring. The housing spring member 23 may be located on an opposing
surface or end of the brush receptacle 24 from the locking element
21. The housing spring member 23 may be a substantially
cantilevered element. Also, the housing spring member 23 may have
its distal end angled upwards so that when the bush holder
apparatus 10 is inserted into the brush receptacle 24, the brush
holder apparatus 10 forces the housing spring member 23 downwards.
In this manner, the housing spring member 23 may apply an upward
force to the brush holder apparatus 10 and assist in retaining the
locking element 21 in the receiving aperture 11. In one embodiment,
the housing spring member 23 may also be made from electrically
insulating materials; a non-limiting example of such a material
would be plastic.
[0026] FIG. 4 shows one embodiment of an insulation displacement
connector (IDC) 30. FIG. 8 shows a bottom view of the same IDC 30.
While it is known in the art to electrically connect a brush holder
to an electric motor field, what is not known is how to achieve
this connection by integrating the securing features and connection
features into the electrical connection member and providing a
robust electrical connection, reduced components, and reduced
assembly time. The IDC 30 may be made from electrically conductive
material; non-limiting examples of such a material are brass,
copper, silver, gold, and aluminum. In one embodiment, an IDC 30
may be made from one, integral flat sheet or pattern using a metal
forming process, as shown in FIG. 7.
[0027] With continued reference to FIG. 4, the IDC 30 may contain a
plurality of displacement members 31 or plates. Each displacement
member 31 may have a cutting portion 33 at its distal end. The
cutting portion 33 may be shaped and sized to receive insulation
coated electrical wire 50, as shown in FIG. 5. Also, the cutting
portion 33 may be shaped and sized such that when force is applied
to the displacement member 31 with wire 50 in place, the cutting
portion 3 displaces the insulation from the wire 50 and an
electrical connection is made between the wire 50 and the
displacement member 31. The cutting portion 33 may also be shaped
and sized such that the insulation may be displaced from the wire
50 without inducing significant damage to the wire 50. One
non-limiting example of the shape of a cutting portion 33 is a V
shape where the wire 50 would lie in the V. The cutting portion 33
may be smaller than the diameter of the insulation on the wire 50
and thus cut the insulation when forced against the wire 50.
[0028] With continued reference to FIG. 4, displacement members 31
may be located along and perpendicular to the longitudinal or
connector axis 37 of the IDC 30. When arranged in this manner, the
top surfaces of displacement members 31 form a brush receiving
plane 35. Also, the displacement members 31 may lie substantially
parallel to each other with their respective cutting portions 33
aligned on a common center line.
[0029] With continued reference to FIG. 4, a plurality of connector
spring members 32 may be located to form opposing sides to the
displacement members 31. The top portion of the spring members 32
may extend above the brush receiving plane 35. The cutting portion
33 of the displacement members 31 may extend below the bottom
portion of the spring members 32. The top portion of the spring
members 32 and the brush receiving plane 35 may form a brush
receiving channel 34. The brush receiving channel 34 may be sized
to grip the brush holder apparatus 10. In this manner, the brush
receiving channel 34 may be wider at its receiving end and narrower
at its distal end. This difference in channel width may allow the
brush holder apparatus 10 to be inserted easily into the receiving
end of the channel 34, but the spring members 32 may grip and apply
contact pressure to the brush holder apparatus 10 at the distal
end. This contact pressure may make an electrical connection
between the brush holder apparatus 10 and the IDC 30 and secure the
brush holder apparatus 10 in the receiving channel 34. The brush
receiving channel 34 may run parallel to the IDC longitudinal axis
37. In one embodiment, the connector spring members 32 may have a
cantilever-shaped portion 36 at their distal ends to grip the brush
holder apparatus 10 and provide an electrical connection.
[0030] FIG. 5 shows a partial view of a field 5, which may include
a laminated stator 51 and field windings 52 (which may be made up
of a plurality of turns of magnet wire, but which are represented
as object 52 in FIG. 5). The field 5 may have a terminal board 40
secured to the field 5. The terminal board 40 may be made from
electrically insulating materials; a non-limiting example of such a
material would be plastic. The terminal board 40 may contain a
plurality of terminal blocks 41. In one embodiment, the terminal
blocks 41 are molded into the terminal board 40. A terminal block
41 may contain a connector receptacle 42. In one embodiment, the
receptacle 42 is molded into the terminal block 41. The connector
receptacle 42 may be sized to receive and fixedly retain an IDC 30.
The connector receptacle 42 may have a wire receptacle 43 sized to
receive and securely retain an electrical wire 50, which may be
connected to the field windings 52. The wire 50 may be insulated in
one embodiment. The wire receptacle 43 may be molded into the
connector receptacle 42. The connector receptacle 42 and the wire
receptacle 43 may be located within the terminal block 41 such that
they cooperate to align the cutting portions 33 of the IDC 30 with
the electrical wire 50.
[0031] With reference to FIGS. 2 and 5, one embodiment may include
two IDCs 30. In another embodiment, the two IDCs 30 may be
positioned on the field 5 opposite each other. In alternative
embodiments, as many IDCs 30 as needed may be used. In another
embodiment, the IDCs 30 may be positioned at corners of a
substantially rectangular field 5. In another embodiment, as many
IDCs 30 may be used as there are brush holder apparatuses 10. In
another embodiment, the IDCs 30 may be positioned on the field 5 to
be aligned with and correspond to the brush receptacles 24 when the
field 5 is installed inside the motor housing 20.
[0032] In one embodiment, a brush holder apparatus 10 may be
fixedly mated with the electric motor housing 20 and obtain
electrical connection with the IDC 30 according to the following
method. With reference to FIGS. 2 and 5-6, the user may align
insulated electrical wire 50 connected to the field windings 52
with the wire receptacle 43 on the terminal block 41 and insert the
wire 50 into the receptacle 43. The user may align the IDC 30 with
the connector receptacle 42 such that the cutting portion 33
engages the electrical wire 50. The user may forcibly insert the
IDC 30 into the connector receptacle 42, thus fixedly attaching the
two elements 30, 42. Forcibly inserting the IDC 30 in the
receptacle 42 may result in the insulation on the outside of the
electrical wire 50 to be removed or pierced by the cutting portion
33, and thus an electrical connection may be made between the wire
50 and the IDC 30. The insertion may also result in the IDC 30
being fixedly mated with the terminal board 40. The user may repeat
this procedure for every IDC 30. With the IDCs 30 secured to the
field 5, the armature 3 may be inserted inside the field 5, and
both 3, 5 may be placed inside the motor housing 20, as previously
described, such that the brush receiving channels 34 of the IDCs 30
align with the brush receptacles 24 of the housing 20.
[0033] Having assembled the field 5, the armature 3, and the
housing 20, the brush holder apparatuses 10 may be installed. As
shown in FIGS. 1-3 and 6, the user may next align the longitudinal
axis 7 of the brush holder apparatus 10 with longitudinal axis of
the brush receptacle 24 (and also with the connector axis 37 and
channel 34 of the IDC 30). The user may forcibly insert the brush
holder apparatus 10 into the brush receptacle 24 with the open end
of the brush holder housing going in first. As the brush holder
apparatus 10 moves into the brush receptacle 24, the brush holder
apparatus 10 may displace the housing spring member 23 downward or
away from the brush holder apparatus 10. In one embodiment, the
brush holder apparatus 10 may be inserted in the brush receptacle
24 until the locking element 21 aligns with the receiving aperture
11. In another embodiment, the brush holder apparatus 10 may be
inserted in the brush receptacle 24 until the locating element 12
rests against the surface 25 of the locking element 21. The user
may align one receiving aperture 11 with one locking element 21
located inside the brush receptacle 24. At this point, the user may
release the brush holder apparatus 10, which will allow the spring
force of the spring member 23 to move the brush holder apparatus 10
in an upward direction, thus seating the locking element 21 into
the receiving aperture 11. The locating element 12 and the locking
element 21 may cooperate to prevent the brush holder housing 9 from
being inserted too far and jamming the commutator 4. The receiving
aperture 11 and the locking element 21 may cooperate to prevent the
brush holder housing 9 from being pushed back out of the motor
housing 20 by the spring force of the brush 8 against the
commutator 4.
[0034] In one embodiment, the brush holder apparatus 10 may have
receiving apertures 11 and locking elements 12 on both its upper
and lower sides, which may be mirror images, thus allowing two
possible insertion orientations one hundred and eighty degrees
apart. By having two possible insertion orientations, it may become
easier for the user to align the brush holder apparatus 10 with the
locking element 21 during assembly; the user does not have to pay
attention as to the specific orientation of the brush holder
apparatus 10 during its insertion into the brush receptacle 24
because either of the two insertions will work.
[0035] In another embodiment, the brush holder apparatuses 10 may
be installed in the motor housing 20 offset from a common axis 7,
as explained previously and shown in FIG. 9. Such offset may allow
more surface-area contact between the brush 8 and the commutator 4
for the same size brush 8, which may increase the life of the brush
8. In one embodiment of offset brush holder apparatuses 10, each
brush holder apparatus 10 may have only one receiving aperture 11
and locking element 12, which may allow only one insertion
orientation and prevent improper assembly.
[0036] With reference to FIGS. 3 and 6, as the brush holder
apparatus 10 is being inserted into the brush receptacle 24, it 10
may move into the brush receiving channel 34 of the IDC 30. The
connector spring members 32 may apply contact pressure to the sides
of the brush holder apparatus 10, as shown in FIG. 6. This contact
pressure may aid in retaining the brush holder apparatus 10 in the
motor housing 20 and may also provide an electrical connection
between the brush holder apparatus 10 and the IDC 30. FIG. 6 does
not show the motor housing 20 that would enclose the IDC 30 and
into which the brush holder apparatus 10 would be inserted. As
shown partly in FIG. 3, the brush holder apparatus 10 may be
retained by the connector spring members 32 at the side that is
urged by the housing spring member 23 and opposite from the side
that receives the locking element 21 in the receiving aperture
11.
[0037] At this point, all of the components of the motor 2 may be
secured such that the brush spring 6 urges the brush 8 to contact
the commutator 4 that is located inside the housing 20 and is
aligned with the brush holder apparatus 10. Electricity may now be
conducted from the field windings 52 through the wire 50 inside the
wire receptacle 43, through the IDC 30 that pierces the insulation
of and makes electrical contact with the wire 50, through the brush
holder housing 9 that is secured inside the IDC channel 34, through
the brush 8 that is housed inside the brush holder housing 9, and
to the commutator 4 that is contacted by the brush 8. By this
method, the brush holder apparatus 10 may be secured inside a motor
2 and may make electrical connection with the field windings 52. In
other embodiments, a motor 2 may include the means disclosed here
to physically secure the brush holder apparatus 10 inside the motor
2 (by virtue of the design of the brush holder apparatus 10 and the
motor housing 20) but use a different means for electrical
connection to the brush holder apparatus 10 (and not have the
disclosed IDC 30). In other embodiments, a motor 2 may include the
means disclosed here for electrical connection to the brush holder
apparatus 10 (by the IDC 30) but use a different means to
physically secure the brush holder apparatus 10 inside the motor 2
(and not use the disclosed design of the brush holder apparatus 10
and the motor housing 20).
[0038] Numerous embodiments have been described, hereinabove. It
will be apparent to those skilled in the art that the above methods
and apparatuses may incorporate changes and modifications without
departing from the general scope of this invention. It is intended
to include all such modifications and alterations in so far as they
come within the scope of the appended claims or the equivalents
thereof
[0039] Having thus described the invention, it is now claimed:
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