CA1163666A - Electric motor brush holder - Google Patents
Electric motor brush holderInfo
- Publication number
- CA1163666A CA1163666A CA000381528A CA381528A CA1163666A CA 1163666 A CA1163666 A CA 1163666A CA 000381528 A CA000381528 A CA 000381528A CA 381528 A CA381528 A CA 381528A CA 1163666 A CA1163666 A CA 1163666A
- Authority
- CA
- Canada
- Prior art keywords
- tube
- spring
- section
- electrode
- holder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
- H01R39/00—Rotary current collectors, distributors or interrupters
- H01R39/02—Details for dynamo electric machines
- H01R39/38—Brush holders
- H01R39/40—Brush holders enabling brush movement within holder during current collection
Landscapes
- Motor Or Generator Current Collectors (AREA)
- Motor Or Generator Frames (AREA)
Abstract
ELECTRIC MOTOR BRUSH HOLDER
ABSTRACT OF THE DISCLOSURE
The disclosure concerns a brush holder 31 for an electric motor comprising a tube member 31 which is provided with an opening at one end through which an electrode 30 slides. A compression spring 35 is held between the electrode and an abutment at the rear end of the tube. At least a pair of opposite side walls 44, 45 of the tube are generally cylindrically curved to define the area in which the compression spring is contained. The cylindrically curved side walls are slit at 50,51 at a point spaced from but adjacent the open end from which the electrode projects leaving a pair of short axial length, flat parallel walls 52, 53 adjacent the open end. The rear edges of the short walls extend across the curved tube at the front of the spring. The rear edges of the short walls furnish a stop for the spring and prevent it from being ejected from the tube. The electrode is attached to the spring at 36.
ABSTRACT OF THE DISCLOSURE
The disclosure concerns a brush holder 31 for an electric motor comprising a tube member 31 which is provided with an opening at one end through which an electrode 30 slides. A compression spring 35 is held between the electrode and an abutment at the rear end of the tube. At least a pair of opposite side walls 44, 45 of the tube are generally cylindrically curved to define the area in which the compression spring is contained. The cylindrically curved side walls are slit at 50,51 at a point spaced from but adjacent the open end from which the electrode projects leaving a pair of short axial length, flat parallel walls 52, 53 adjacent the open end. The rear edges of the short walls extend across the curved tube at the front of the spring. The rear edges of the short walls furnish a stop for the spring and prevent it from being ejected from the tube. The electrode is attached to the spring at 36.
Description
ELECTRIC MOTOR BRUSH HOLDER
BACKGROU~D OF TNE INVENTION
~ The present invention relates to a brush for an electric motor and more particularly to a holder for the brush.
The electrode or contact of the brush of an electric motor is installed in a holder. The holder con-taining the electrode may be inserted in an appropriate positioning device in the housing of an electric motor and may be removed therefrom for replacement.
10~ The electrode comprises a contact member which is preferably of a carbon type. It has a profiled and usually rectangular cross-section. It is suf~iciently elongated to continuously present a contacting surface to the commutator on the armature as the elongated carbon contact member wears.
The elongated carbon contact member is housed in a hollow tubular holder of a cross-section which generally matches the cross-section of the electrode. But, the housing , .
may be provided with other cross-sectional shapes, includin~
a partly cylindrical cross-sectional shape on two opposing : ~ .
~ ' ' , . . '' .
: , ~ i 63666
BACKGROU~D OF TNE INVENTION
~ The present invention relates to a brush for an electric motor and more particularly to a holder for the brush.
The electrode or contact of the brush of an electric motor is installed in a holder. The holder con-taining the electrode may be inserted in an appropriate positioning device in the housing of an electric motor and may be removed therefrom for replacement.
10~ The electrode comprises a contact member which is preferably of a carbon type. It has a profiled and usually rectangular cross-section. It is suf~iciently elongated to continuously present a contacting surface to the commutator on the armature as the elongated carbon contact member wears.
The elongated carbon contact member is housed in a hollow tubular holder of a cross-section which generally matches the cross-section of the electrode. But, the housing , .
may be provided with other cross-sectional shapes, includin~
a partly cylindrical cross-sectional shape on two opposing : ~ .
~ ' ' , . . '' .
: , ~ i 63666
-2-sides, in order to provlde within the holder itself a sup-port ~or ot~ller ele~ents, ~like the electrode biasin~ spring, as hereinafter described.
- A contact pressure spring engages one end of the carbon contact member or electrode and is preferably secured thereto. The spring is positioned in the holder and is co~-pressed and charged between the end of the electrode within tne holder and an abutment at the opposite end of the holder so that the electrode projects from an opening in the end of the holder. At least two opposite side walls o~ the holder are bowed out~ardly in matching cylindrical ~orm to accom-~odate the cylindrical shape of the pressure spring. The bowed out walls extend substantially the length of the hol-der up to the end from which the electrode emerges. It is 1~ known to provide abutment means or other spring motion hal-ting means in the holder to prevent the spring from ex-tending all the way out of the holder when the carbon elec-trode is fully worn away. Known abutment means include a separate element, separate from and supported inside the holder.
A brush and holder assembly of the type thus far described is disclosed in U.S. Patent 3,050,649.
SU~I~ARY OF THE INVENTION
The invention relates to means formed in the hol-der for preventing the electrode biasing spring from pushingfully out of the holder. Instead of a separate retention element havin~ to be separately installed, according to the invention, the holder itself is con~igured upon initial fabrication to prevent the spring from moving out of the holder. Further the holder is shaped to properly guide and support the electrode against displacement and lateral and rotational motion.
The holder has the previously mentioned generally cylindrically rounded, or outwardly bowed opposite side
- A contact pressure spring engages one end of the carbon contact member or electrode and is preferably secured thereto. The spring is positioned in the holder and is co~-pressed and charged between the end of the electrode within tne holder and an abutment at the opposite end of the holder so that the electrode projects from an opening in the end of the holder. At least two opposite side walls o~ the holder are bowed out~ardly in matching cylindrical ~orm to accom-~odate the cylindrical shape of the pressure spring. The bowed out walls extend substantially the length of the hol-der up to the end from which the electrode emerges. It is 1~ known to provide abutment means or other spring motion hal-ting means in the holder to prevent the spring from ex-tending all the way out of the holder when the carbon elec-trode is fully worn away. Known abutment means include a separate element, separate from and supported inside the holder.
A brush and holder assembly of the type thus far described is disclosed in U.S. Patent 3,050,649.
SU~I~ARY OF THE INVENTION
The invention relates to means formed in the hol-der for preventing the electrode biasing spring from pushingfully out of the holder. Instead of a separate retention element havin~ to be separately installed, according to the invention, the holder itself is con~igured upon initial fabrication to prevent the spring from moving out of the holder. Further the holder is shaped to properly guide and support the electrode against displacement and lateral and rotational motion.
The holder has the previously mentioned generally cylindrically rounded, or outwardly bowed opposite side
3~ ~lalls which are shaped for receiving the cylindrical profile - 3 .
.
, 1 J 636~6 of the bias s~ring. These bowed ~valls extend substantially up to the open end of the holder from which the electrode projects. Near that open end of the holder, the opposite side walls ære slit across their width. This defines a transition t'ra separates the spring motion stop section of the holder nea- the open end from the bowed wall main section of the holder. Instead of having the bowed walls, the section OL the holder at the open end defines an opening into the holder that is completely rectangular. Thus, the end section OL the holder provides two opposite sides which are essentially a chord or secant across the ends of the cylindrically curved walls of the main section of the holder. The rear ed~es of the unbowed sides provide an abut~ent against which the pressure spring, at the electrode end thereof, ~2y bear so that the spring will not pùsh itself out of the holder. The spring is thus retained in the holder a~ one end by the rear abutment of the holder and at the opposite end by the unbowed stop section of t~e holder at ~he open end. More generally expressed, in at least one dimension across the holder, the main section is wider than the spring stop section, so that the spring moving toward the stop section will be blocked from moving through that section.
Interengagement or attachment of the electrode and of the spring which cannot leave the holder ensures that the electrode will not fall out of the holder while the entire brush structure is being transported or inserted in or re-moved ~rom a motor or a~ the end of the useful life of the electrode.
The end of the holder away from the open end carries an out~ardly projecting abutment which limits the insertion of the entire holder into a retainer for the brush in the motor s~ructure and thereby positions the brush holder within the motor structure.
The open end of the holder is a]so provided with an extension ~vhich, preferably after insertion of the brush ~ .......... . .
asse~ly into the retainer therefor in the electric motor, may be bent up to'assist in retaining the holder in the re-tainer and to provide a connector for an electric lead for the brush.
- The primary object oE the present invention, therefore, is to provide a holder ior a brush electrode for an electxic motor, wherein a,compression sprin~ that is com-pressed within the brush holder drives the contact membe~ or electrode out through one end of the brush holder.
Tha invention further has for its object the arrangement o~ the holder so that a stop for the compression spring is provided adJacent the end of the holder through which the electrode projects.
Another object of the invention is to retain the electrode bias spring in the holder without the need for assembly of extra elements in the holder.
A further object of the invention is to guide motion of the electrode as the motor operates and to keep a desired orientation for the electrode.
A ~urther object of the invention is to ~orm the brush holder from a simple tubular structure which is r~c-tangular at the open end from which the electrode emerges and which is cylindrical bacX from that open end to accom-modate the compression spring and which inherently provides an abutment and stop for the compression spring to ensure that the compression spring always stays within the holder.
The foregoing and other objects and features of ``
the present invention will become apparent from the fol-lowing description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a generalized schematic view of an electric motor showing the position which the brush holder of the present invention occupies in an electric motor.
Figure-2 is a view, partly in cross-section~ of the brush holder of the present invention, .
~5~ ~l 63fi6~
Figure 3 is a view in perspective showinc~ the brush and holder prior to completion.
~igure 4 is a view in perspective correspondinr, to Figrure 3 sho\~ing the completed assembly of a brush~
Figure 5 is a cross-sectional view of the motor ta~en along line 5-5 of Figure l looking in the direction o~
the arrows and showing in particular a pair of brush re- -tainers in the motor and the brush of the invention inserted therein.
Figure 6 is a view taken from line 6-6 of Figure 5 looking in the direction o:E the arrows and showin~ the brush in the electric motor~
Figure 7 is a view o~ one side of the brush holder, without the electrode present, in the direction of arrows 7-7 of Figure 9.
- Figure 8 is an end view of the brush holder taken from the right side in Figure 7.
Figure 9 is a top view of the brush holder of Figure 7 viewed in the direction of arrows 9-9 of Figure 7.
Figure 10 is the opposite side view of the brush holder of Figure 7 and showing the seam in the tube.
Figure 11 is a side view of the contact or electrode of the brush with the biasing spring connected thereto~
DESCRIPTIO~ OF A PREFERRED EMBODIMENT
Referring to Figures 1 and 5 one embodimen~ of an electric motor 20 is here shown mounted on a support 19.
The illustrated motor is a bypass-type blower motor for creating suction in an electric vacuum cleaner, but the application of the invention is not limited to any particular motor.
The motor includes a conventional com~utator 21 on the armature 22 of the motor. The motor drives a sha~t 23 to rotate and this in turn rotates the armature inside the stator pole pieces 24. The shaft 23 drives the blower motor main fan 25 and motor cooling fan 26 in the usual manner.
.
, ..
`1 ~ 63666 The support 19 is provided with a lower bearing 27 a~d ~n up~er ~ea~ing 2S ~hich rotatively sup~or~ -the shaît 23 and support the electric motor 20. The bearings 27 and 28 are in turn supported in housings 28a and 28b at the top and bottom. The housings may be directly interconnected or may be connected together by the stator pole pieces 2~ of the motor. The housings 28a and 28b are,respective plastic moldings, for instance.
The housing 28b carries integrally formed holder retainers 73, which are essentially tubular members, each adapted to receive the holder hereina~ter described and retain it in position. When the holders are inserted into the respective retainers 73, the contact member or electrode 30 of each brush bears against the commutator 21 of the motor armature in order,to provide appropriate contact therewith for electric current as is well known in the art. Each,of the retainers 73 is provided with a removable cap 78 preferably of resilient insulating material in order,to ensure that the brush remains within the holder retainer 73. Cap 78 is a snap-on cap having a re-entrant flange 79 which in turn engages a flange 8~ on the holder retainer 73 to provide appropriate means for holding the brush in place and also for retaining the brush against being accidentally snapped out. Since the caps 79 are of 2~ resilient material they may be removed by prying against the re-entrant member section 79 in order to permit removal of the brush which is retained,by the holder retainer 73 and permit replacement thereof. ' ~ -The brush includes a conventional carbon electrode 30 with an end 40 which engages the commutator 21. The electrode 30 has a rectangular cross-section, uniform along its length. The electrode is housed in the holder 31.
The electrode holder 31 is a tubular member - initiallY formed from flat sheet material that has been ' 3~ folded over to the generally rectangular hollow cross-section seen in Fig. 8. The folded sheet is appropriately .
.... ,. ......... , .. . _ .. ,.. . .. ~ ........ . . . . ...... ... ... . . . . .
~ :
~` J ~3666 se~ed at 3~ s seen in ~lgure l0, in order to provide a brush holder s~ructure which is substantially smooth inside and outside. The seam is either cold welded or otherwise interengaged and secured in order to integrate and interlock S the seam ends.
A coiled, cylindrical cross-section, compression spring 35 is positioned inside the brush holder 31 and it engages the in~vard or rearward end of electrode 30. The en-gagement is through the turn down section 36 at the end of the spri~g 35 being received in the opening 37 of the elec-trode 30. The engagement of the spring 35 with the elec-trode 30 ensures that the electrode 30 will not ~all out of the brush holder 31 at the end of the useful life of the electrode and during transportation, insertion or removal of llqJj~15 the entire brush structure in the ~uc~ retainer 73 of the il motor.
The brush holder 31 is tubular, and is a rec-tangular tube with at least two opposite, outwardly bowed sides. One pair of opposite side walls 41 and 42 are parallel to each other and are essentially planar. A second pair of opposite side walls 44 and 45 are, at their upper and lower margins adjacent the walls 41 and 42, parallel to each other, but they are bowed to a generally cylindrically `
curved form longitudinally thereof along the central areas 46 and 47 t'nereof. The bowed areas 46 and 47 of the walls 44 and 45 accommodate the cylindrical profile of the com-pression spring 35.
Toward the open end of the holder 31, the bowed areas terminate at the slits 50 and 51 formed in the side walls 44 and 45, leaving the flat unbowed, front end stop sections 52 and 53 on the opposite side which are extensions of the walls 44 and 45. More generally stated, the distance across the holder 31 in at least one dimension, the dimension throu~h the bowed areas 46 and 47 of the opposite walls 44 and 45, is greater than the same dimension through .
' .. .
,..... ,. ,.,... . ......... . . ...... . ... ... . .. . ... .... .. , ~.
`~ ` I i 6~666 the un`~o~ed c~rrespondin~ s;de wa~ls ~1 and ~2 de:Eining the stop sections~ The rearwardlY facing edges of the flat stop sections 5?. and 53 within the holder act together as a front stop for the front end 54 of the comprèssion spring 35.
~lso, tney guide the axial motion and the orientation of the electrode 30 through the holder. Furthermore, together with the holder side walls 41 and 42, the stop sections are shaped to define an opening of substantially-the same.cross-.
section as the contact member 30, whieh prohibits-lateral shifting and rotation of the contact member 30.
The xear end of the tube 31, at the end opposite the stop sections 52 and 53, is provided with extensions 60, .
61 which are bent inwardly from the position o~ Figures 2 and 3 to the position shown in Figure 4 after the spring 35 `
l~ has been inserted, to retain the spring compressed.`
The compression spring 35 is preferably made o~ a conductive metal~ Because it bears between the rear or in-side end of the electrode 30 and the bent in holder exten-sions 61, which hold the sprin~ in position, an electrical path is provided from the connector 65 for the electric lead throu~h the tube to the electrode 30. In addition, because the electrode 30 preferably has a current conducting fit with the stop sections 52 and 53 of the tube, current con-duction occurs from the tube to the electrode at that point.
When the brush holder 31 is inserted into the holder retainer 73, it is pushed in from the rear end of the retainer mechanism in a direction shown by the arrow 70 in Fig. 5 and is pushed home entirely within the retainer 73 so that the contact surface 40 of the electrode 30 is pushed against the commutator 21. The sprin~ 35 is thereby `
compressed. The cap 78 is snapped on over the flange 80 of the holder retainer 73 after the holder is inserted.
The inward movement of the brush of the present invention into the retainer 73 is controlled by the lateral e~tension 74 from the re-r end of one of the side walls of .
.. .. . . . . .. . . .... . . . . . ............... . .. . .
':
`
`` 3 ~ 636~6 _9_ the brus~l holder 31, in this cas~ an e~te~sion from the side wall 42-46 at the rear. The ex-tension 74 bears against the rearward edge 75 of the~ holder retainer 73 and limits the inward movement of the brush holder. The brush is then re-- 5 tained in position by the electrode 30 bearing at its con-tact end 40 against the commutator 21 and by the rear end of the electrode being retained in position by the cap 78.
The holder retainer 73 of the motor structure lacks longitudinal slots or openings. Therefore, the con-nector 6S on the holder for the electric lead which connectsthe brush into the motor circuit is initially arranged flat as shown in Figure 3. After the holder is inserted into the retainer 73~ the connector 65 is bent and raised to a posi-tion where a motor lead 66 may be connected to it, as shown in Figure 6. The motor lead is, in turn, connected with the stator pole pieces 24.
It uill thus be seen that the brush holder of the present invention is one in which a simplified brus'n holder tube is created, wherein a compression spring is captured between the closed rear end of the tube and the opposite fro~t end out of which the electrode is spring biased. The compression spring is thus compressed between the electrode and the rear end of the holder tube. However, when the tube is being transported and prior to its insertion in the motor 2~ or its removal from the motor, and therefore when the elec-trode is not engaged with the commutator, a stop is provided in the holder for the spring so that it will not be ejected from the tube. The tube itself is configured at a stop section, which has a smaller cross-section than the spring, to provide the stop for the spring. Interconnection of the electrode and the spring prevents the electrode from being separated~ The tube itself provides a simple way of con-necting the electrode in circuit with the motor and provides inherently within it appropriate electrical connection to the electrode so that a connection to a tab extending from ..... . .
.
C.le tube ~-iill provid~ electrical connection bet~.veen the electrode and the remainder of the circuit.
In the foregoin~, the present invention has been described solely in connection with a preferred illustrative embodiment. Since many variations and modifications of the present invention will now be obvious to those skilled in the art, it is preferred that the scope of this invention be determined not by the specific disclosures herein contained but only by the appended claims.
.
, 1 J 636~6 of the bias s~ring. These bowed ~valls extend substantially up to the open end of the holder from which the electrode projects. Near that open end of the holder, the opposite side walls ære slit across their width. This defines a transition t'ra separates the spring motion stop section of the holder nea- the open end from the bowed wall main section of the holder. Instead of having the bowed walls, the section OL the holder at the open end defines an opening into the holder that is completely rectangular. Thus, the end section OL the holder provides two opposite sides which are essentially a chord or secant across the ends of the cylindrically curved walls of the main section of the holder. The rear ed~es of the unbowed sides provide an abut~ent against which the pressure spring, at the electrode end thereof, ~2y bear so that the spring will not pùsh itself out of the holder. The spring is thus retained in the holder a~ one end by the rear abutment of the holder and at the opposite end by the unbowed stop section of t~e holder at ~he open end. More generally expressed, in at least one dimension across the holder, the main section is wider than the spring stop section, so that the spring moving toward the stop section will be blocked from moving through that section.
Interengagement or attachment of the electrode and of the spring which cannot leave the holder ensures that the electrode will not fall out of the holder while the entire brush structure is being transported or inserted in or re-moved ~rom a motor or a~ the end of the useful life of the electrode.
The end of the holder away from the open end carries an out~ardly projecting abutment which limits the insertion of the entire holder into a retainer for the brush in the motor s~ructure and thereby positions the brush holder within the motor structure.
The open end of the holder is a]so provided with an extension ~vhich, preferably after insertion of the brush ~ .......... . .
asse~ly into the retainer therefor in the electric motor, may be bent up to'assist in retaining the holder in the re-tainer and to provide a connector for an electric lead for the brush.
- The primary object oE the present invention, therefore, is to provide a holder ior a brush electrode for an electxic motor, wherein a,compression sprin~ that is com-pressed within the brush holder drives the contact membe~ or electrode out through one end of the brush holder.
Tha invention further has for its object the arrangement o~ the holder so that a stop for the compression spring is provided adJacent the end of the holder through which the electrode projects.
Another object of the invention is to retain the electrode bias spring in the holder without the need for assembly of extra elements in the holder.
A further object of the invention is to guide motion of the electrode as the motor operates and to keep a desired orientation for the electrode.
A ~urther object of the invention is to ~orm the brush holder from a simple tubular structure which is r~c-tangular at the open end from which the electrode emerges and which is cylindrical bacX from that open end to accom-modate the compression spring and which inherently provides an abutment and stop for the compression spring to ensure that the compression spring always stays within the holder.
The foregoing and other objects and features of ``
the present invention will become apparent from the fol-lowing description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a generalized schematic view of an electric motor showing the position which the brush holder of the present invention occupies in an electric motor.
Figure-2 is a view, partly in cross-section~ of the brush holder of the present invention, .
~5~ ~l 63fi6~
Figure 3 is a view in perspective showinc~ the brush and holder prior to completion.
~igure 4 is a view in perspective correspondinr, to Figrure 3 sho\~ing the completed assembly of a brush~
Figure 5 is a cross-sectional view of the motor ta~en along line 5-5 of Figure l looking in the direction o~
the arrows and showing in particular a pair of brush re- -tainers in the motor and the brush of the invention inserted therein.
Figure 6 is a view taken from line 6-6 of Figure 5 looking in the direction o:E the arrows and showin~ the brush in the electric motor~
Figure 7 is a view o~ one side of the brush holder, without the electrode present, in the direction of arrows 7-7 of Figure 9.
- Figure 8 is an end view of the brush holder taken from the right side in Figure 7.
Figure 9 is a top view of the brush holder of Figure 7 viewed in the direction of arrows 9-9 of Figure 7.
Figure 10 is the opposite side view of the brush holder of Figure 7 and showing the seam in the tube.
Figure 11 is a side view of the contact or electrode of the brush with the biasing spring connected thereto~
DESCRIPTIO~ OF A PREFERRED EMBODIMENT
Referring to Figures 1 and 5 one embodimen~ of an electric motor 20 is here shown mounted on a support 19.
The illustrated motor is a bypass-type blower motor for creating suction in an electric vacuum cleaner, but the application of the invention is not limited to any particular motor.
The motor includes a conventional com~utator 21 on the armature 22 of the motor. The motor drives a sha~t 23 to rotate and this in turn rotates the armature inside the stator pole pieces 24. The shaft 23 drives the blower motor main fan 25 and motor cooling fan 26 in the usual manner.
.
, ..
`1 ~ 63666 The support 19 is provided with a lower bearing 27 a~d ~n up~er ~ea~ing 2S ~hich rotatively sup~or~ -the shaît 23 and support the electric motor 20. The bearings 27 and 28 are in turn supported in housings 28a and 28b at the top and bottom. The housings may be directly interconnected or may be connected together by the stator pole pieces 2~ of the motor. The housings 28a and 28b are,respective plastic moldings, for instance.
The housing 28b carries integrally formed holder retainers 73, which are essentially tubular members, each adapted to receive the holder hereina~ter described and retain it in position. When the holders are inserted into the respective retainers 73, the contact member or electrode 30 of each brush bears against the commutator 21 of the motor armature in order,to provide appropriate contact therewith for electric current as is well known in the art. Each,of the retainers 73 is provided with a removable cap 78 preferably of resilient insulating material in order,to ensure that the brush remains within the holder retainer 73. Cap 78 is a snap-on cap having a re-entrant flange 79 which in turn engages a flange 8~ on the holder retainer 73 to provide appropriate means for holding the brush in place and also for retaining the brush against being accidentally snapped out. Since the caps 79 are of 2~ resilient material they may be removed by prying against the re-entrant member section 79 in order to permit removal of the brush which is retained,by the holder retainer 73 and permit replacement thereof. ' ~ -The brush includes a conventional carbon electrode 30 with an end 40 which engages the commutator 21. The electrode 30 has a rectangular cross-section, uniform along its length. The electrode is housed in the holder 31.
The electrode holder 31 is a tubular member - initiallY formed from flat sheet material that has been ' 3~ folded over to the generally rectangular hollow cross-section seen in Fig. 8. The folded sheet is appropriately .
.... ,. ......... , .. . _ .. ,.. . .. ~ ........ . . . . ...... ... ... . . . . .
~ :
~` J ~3666 se~ed at 3~ s seen in ~lgure l0, in order to provide a brush holder s~ructure which is substantially smooth inside and outside. The seam is either cold welded or otherwise interengaged and secured in order to integrate and interlock S the seam ends.
A coiled, cylindrical cross-section, compression spring 35 is positioned inside the brush holder 31 and it engages the in~vard or rearward end of electrode 30. The en-gagement is through the turn down section 36 at the end of the spri~g 35 being received in the opening 37 of the elec-trode 30. The engagement of the spring 35 with the elec-trode 30 ensures that the electrode 30 will not ~all out of the brush holder 31 at the end of the useful life of the electrode and during transportation, insertion or removal of llqJj~15 the entire brush structure in the ~uc~ retainer 73 of the il motor.
The brush holder 31 is tubular, and is a rec-tangular tube with at least two opposite, outwardly bowed sides. One pair of opposite side walls 41 and 42 are parallel to each other and are essentially planar. A second pair of opposite side walls 44 and 45 are, at their upper and lower margins adjacent the walls 41 and 42, parallel to each other, but they are bowed to a generally cylindrically `
curved form longitudinally thereof along the central areas 46 and 47 t'nereof. The bowed areas 46 and 47 of the walls 44 and 45 accommodate the cylindrical profile of the com-pression spring 35.
Toward the open end of the holder 31, the bowed areas terminate at the slits 50 and 51 formed in the side walls 44 and 45, leaving the flat unbowed, front end stop sections 52 and 53 on the opposite side which are extensions of the walls 44 and 45. More generally stated, the distance across the holder 31 in at least one dimension, the dimension throu~h the bowed areas 46 and 47 of the opposite walls 44 and 45, is greater than the same dimension through .
' .. .
,..... ,. ,.,... . ......... . . ...... . ... ... . .. . ... .... .. , ~.
`~ ` I i 6~666 the un`~o~ed c~rrespondin~ s;de wa~ls ~1 and ~2 de:Eining the stop sections~ The rearwardlY facing edges of the flat stop sections 5?. and 53 within the holder act together as a front stop for the front end 54 of the comprèssion spring 35.
~lso, tney guide the axial motion and the orientation of the electrode 30 through the holder. Furthermore, together with the holder side walls 41 and 42, the stop sections are shaped to define an opening of substantially-the same.cross-.
section as the contact member 30, whieh prohibits-lateral shifting and rotation of the contact member 30.
The xear end of the tube 31, at the end opposite the stop sections 52 and 53, is provided with extensions 60, .
61 which are bent inwardly from the position o~ Figures 2 and 3 to the position shown in Figure 4 after the spring 35 `
l~ has been inserted, to retain the spring compressed.`
The compression spring 35 is preferably made o~ a conductive metal~ Because it bears between the rear or in-side end of the electrode 30 and the bent in holder exten-sions 61, which hold the sprin~ in position, an electrical path is provided from the connector 65 for the electric lead throu~h the tube to the electrode 30. In addition, because the electrode 30 preferably has a current conducting fit with the stop sections 52 and 53 of the tube, current con-duction occurs from the tube to the electrode at that point.
When the brush holder 31 is inserted into the holder retainer 73, it is pushed in from the rear end of the retainer mechanism in a direction shown by the arrow 70 in Fig. 5 and is pushed home entirely within the retainer 73 so that the contact surface 40 of the electrode 30 is pushed against the commutator 21. The sprin~ 35 is thereby `
compressed. The cap 78 is snapped on over the flange 80 of the holder retainer 73 after the holder is inserted.
The inward movement of the brush of the present invention into the retainer 73 is controlled by the lateral e~tension 74 from the re-r end of one of the side walls of .
.. .. . . . . .. . . .... . . . . . ............... . .. . .
':
`
`` 3 ~ 636~6 _9_ the brus~l holder 31, in this cas~ an e~te~sion from the side wall 42-46 at the rear. The ex-tension 74 bears against the rearward edge 75 of the~ holder retainer 73 and limits the inward movement of the brush holder. The brush is then re-- 5 tained in position by the electrode 30 bearing at its con-tact end 40 against the commutator 21 and by the rear end of the electrode being retained in position by the cap 78.
The holder retainer 73 of the motor structure lacks longitudinal slots or openings. Therefore, the con-nector 6S on the holder for the electric lead which connectsthe brush into the motor circuit is initially arranged flat as shown in Figure 3. After the holder is inserted into the retainer 73~ the connector 65 is bent and raised to a posi-tion where a motor lead 66 may be connected to it, as shown in Figure 6. The motor lead is, in turn, connected with the stator pole pieces 24.
It uill thus be seen that the brush holder of the present invention is one in which a simplified brus'n holder tube is created, wherein a compression spring is captured between the closed rear end of the tube and the opposite fro~t end out of which the electrode is spring biased. The compression spring is thus compressed between the electrode and the rear end of the holder tube. However, when the tube is being transported and prior to its insertion in the motor 2~ or its removal from the motor, and therefore when the elec-trode is not engaged with the commutator, a stop is provided in the holder for the spring so that it will not be ejected from the tube. The tube itself is configured at a stop section, which has a smaller cross-section than the spring, to provide the stop for the spring. Interconnection of the electrode and the spring prevents the electrode from being separated~ The tube itself provides a simple way of con-necting the electrode in circuit with the motor and provides inherently within it appropriate electrical connection to the electrode so that a connection to a tab extending from ..... . .
.
C.le tube ~-iill provid~ electrical connection bet~.veen the electrode and the remainder of the circuit.
In the foregoin~, the present invention has been described solely in connection with a preferred illustrative embodiment. Since many variations and modifications of the present invention will now be obvious to those skilled in the art, it is preferred that the scope of this invention be determined not by the specific disclosures herein contained but only by the appended claims.
Claims (9)
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:-
1. A brush holder for the brush electrode of an electric motor, said brush holder comprising:
a tube that is open at one end for receiving and retaining an electrode which is slidably mounted in said tube and which is slidable out of said tube open end; said tube being adapted to retain a compression spring therein for biasing an electrode out of said tube open end; an abut-ment in said tube away from said tube open end for being abutted by a spring in said tube, wherein a spring in said tube is adapted to be compressed between said abutment and an electrode within said tube; said tube having a main sec-tion with a cross-section sized for receiving a spring for movement through said tube and for compression in said tube;
a stop section for a spring being defined in and by said tube near said tube open end; said stop section being shaped and placed to be engaged by and block the pathway of a spring out of said tube open end while per-mitting an electrode in said tube to move through said tube open end;
said electrode being substantially rectangular in cross-section and said spring being substantially cylindri-cal in cross-section;
said tube main section including opposite walls which are curved generally to match the cylindrical curva-ture of the cross-section of said spring and to provide a complete retainer for said spring;
said stop section defining an opening in said tube which is generally rectangular and which is shaped corres-pondingly to the cross-sectional profile of said electrode passing through said stop section for prohibiting lateral shifting and rotation of said electrode; said main tube section opposed walls projecting outwardly of said tube holder further than the corresponding walls of said tube stop section.
a tube that is open at one end for receiving and retaining an electrode which is slidably mounted in said tube and which is slidable out of said tube open end; said tube being adapted to retain a compression spring therein for biasing an electrode out of said tube open end; an abut-ment in said tube away from said tube open end for being abutted by a spring in said tube, wherein a spring in said tube is adapted to be compressed between said abutment and an electrode within said tube; said tube having a main sec-tion with a cross-section sized for receiving a spring for movement through said tube and for compression in said tube;
a stop section for a spring being defined in and by said tube near said tube open end; said stop section being shaped and placed to be engaged by and block the pathway of a spring out of said tube open end while per-mitting an electrode in said tube to move through said tube open end;
said electrode being substantially rectangular in cross-section and said spring being substantially cylindri-cal in cross-section;
said tube main section including opposite walls which are curved generally to match the cylindrical curva-ture of the cross-section of said spring and to provide a complete retainer for said spring;
said stop section defining an opening in said tube which is generally rectangular and which is shaped corres-pondingly to the cross-sectional profile of said electrode passing through said stop section for prohibiting lateral shifting and rotation of said electrode; said main tube section opposed walls projecting outwardly of said tube holder further than the corresponding walls of said tube stop section.
2. The combination of claim 1, wherein for de-fining a transition between said main tube section and said stop section, said opposite side walls of said tube being slit between said curved portions thereof at said main tube section and the same said side walls at said stop section, defining edges of said stop section facing toward said main section for serving as an abutment for said spring moving out of said holder open end.
3. The brush holder of claim 2, wherein said tube is comprised of electrically conductive material.
4. The holder of claim 3, wherein said tube carries an electrical connector thereon for electrically connecting said brush holder to a motor.
5. The brush holder of claim 4, wherein said connector comprises a tab located at said open end of said tube; said tab being bendable with respect to said holder to a position where it may receive a connection to the motor.
6. The brush holder of claim 2, wherein said tube is defined by sides and the slit across some of said sides thereof for defining a transition between said tube stop section and said tube main section; said stop section having an edge thereof at said transition which faces into said tube and toward said tube main section and this said edge of said stop section serving as said stop for said spring.
7. In combination, the brush holder of claim 6 and a compression spring in said tube which is captured-between an electrode in said tube and said abutment away from said tube open end; said compression spring extending longitudinally of said tube and being compressible in said tube in accordance with the movement of an electrode within said tube; said tube main section having a cross-section sized for receiving said spring for axial movement through said tube;
an electrode slidably supported in said tube for axial sliding movement through said tube stop section and through said tube open end against the compression of said spring and also in a direction outwardly of said tube in response to the bias of said spring.
an electrode slidably supported in said tube for axial sliding movement through said tube stop section and through said tube open end against the compression of said spring and also in a direction outwardly of said tube in response to the bias of said spring.
8. The brush holder of claim 7, wherein said tube main section includes two opposed walls which are generally rounded in shape axially along said tube to match the profile of a spring in said tube main section and for containing a spring; said tube main section opposed walls projecting outwardly of said holder further than the corresponding walls of said tube stop section.
9. The brush holder of claim 1, further com-prising a stop member provided on the said brush holder and away from said brush holder open end for serving as an index with respect to the structure of an electric motor for positioning said brush holder with respect to an electric motor.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US16877380A | 1980-07-11 | 1980-07-11 | |
| US168,773 | 1980-07-11 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1163666A true CA1163666A (en) | 1984-03-13 |
Family
ID=22612870
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000381528A Expired CA1163666A (en) | 1980-07-11 | 1981-07-10 | Electric motor brush holder |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0044113B1 (en) |
| JP (1) | JPS5731073U (en) |
| AU (1) | AU544624B2 (en) |
| CA (1) | CA1163666A (en) |
| DE (1) | DE3168621D1 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3220877A1 (en) * | 1982-06-03 | 1983-12-08 | Vorwerk & Co Interholding Gmbh, 5600 Wuppertal | BRUSH HOLDER ON ELECTRIC MOTORS EQUIPPED WITH EMISSION CONTROLLER, IN PARTICULAR FOR HOUSEHOLD APPLIANCES LIKE VACUUM CLEANERS OR THE LIKE |
| US5227688A (en) * | 1990-09-27 | 1993-07-13 | Mitsubishi Denki K. K. | Brush holder for vehicular A.C. generator |
| JPH04138051A (en) * | 1990-09-27 | 1992-05-12 | Mitsubishi Electric Corp | Brush holder of ac generator for vehicle |
| JP2006203962A (en) * | 2005-01-18 | 2006-08-03 | Matsushita Electric Ind Co Ltd | Electric air blower |
| DE102008021067A1 (en) * | 2008-04-26 | 2009-11-05 | Ing. Lang & Menke Gmbh | Carbon guide for carbon brush in electric motor, has arcuate sheet metal part with which two end edges are merged together in edge-to-edge manner, where end edges are fixed together by laser welding spot |
| IT202000014803A1 (en) * | 2020-06-19 | 2021-12-19 | R M D Components Italia S R L | Winder for recharging an electric or hybrid vehicle |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3050649A (en) * | 1958-08-18 | 1962-08-21 | Amherst Metal Products Inc | Motor brush holder |
| US3177388A (en) * | 1960-03-18 | 1965-04-06 | Singer Co | Brush holder assembly for electric motor |
| DE1763883C3 (en) * | 1968-08-29 | 1980-06-12 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Brush holder |
| US3955113A (en) * | 1974-11-27 | 1976-05-04 | General Signal Corporation | Brush holder with means for limiting travel of brush spring |
| DE7626989U1 (en) * | 1976-08-28 | 1976-12-16 | Robert Bosch Gmbh, 7000 Stuttgart | Brush holders for electrical machines |
-
1981
- 1981-07-09 DE DE8181200790T patent/DE3168621D1/en not_active Expired
- 1981-07-09 EP EP19810200790 patent/EP0044113B1/en not_active Expired
- 1981-07-10 CA CA000381528A patent/CA1163666A/en not_active Expired
- 1981-07-10 AU AU72746/81A patent/AU544624B2/en not_active Ceased
- 1981-07-11 JP JP10335281U patent/JPS5731073U/ja active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5731073U (en) | 1982-02-18 |
| DE3168621D1 (en) | 1985-03-14 |
| EP0044113B1 (en) | 1985-01-30 |
| AU7274681A (en) | 1982-01-14 |
| AU544624B2 (en) | 1985-06-06 |
| EP0044113A1 (en) | 1982-01-20 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |