US3601645A - Electrical contact brushes - Google Patents

Electrical contact brushes Download PDF

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Publication number
US3601645A
US3601645A US825305A US3601645DA US3601645A US 3601645 A US3601645 A US 3601645A US 825305 A US825305 A US 825305A US 3601645D A US3601645D A US 3601645DA US 3601645 A US3601645 A US 3601645A
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US
United States
Prior art keywords
metal
metallic layer
layer
electrical
brush
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 - Lifetime
Application number
US825305A
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English (en)
Inventor
Colin Whiteheart
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Morganite Carbon Ltd
Original Assignee
Morganite Carbon Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Morganite Carbon Ltd filed Critical Morganite Carbon Ltd
Application granted granted Critical
Publication of US3601645A publication Critical patent/US3601645A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • H01R39/36—Connections of cable or wire to brush
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49117—Conductor or circuit manufacturing
    • Y10T29/49119—Brush

Definitions

  • An electrical brush comprises a metal-and-carbon containing body and a metallic layer to which an electrical conductor is or may be secured and electrically connected.
  • the metal-and-carbon containing body is sintered with the metallic layer in an area which is greater than the area at the connection of the electrical conductor to the layer.
  • This invention relates to electrical contact brushes and to the manner in which a flexible electrical conductor is attached to the'body of the brush.
  • the present invention seeks to overcome these disad-.
  • an electrical contact brush comprises a metal-and-carbon containing body, a metallic layer sintered with said body, and electrical conductor means secured to said metallic layer and electrically connected therewith, said metallic layer having a greater tensile strength than that of said body.
  • the brush body may be made of a number of materials known in the art of electrical brush manufacture. Thus it may be selected from a wide range of materials going from a mixture of carbon with various metals or alloys (for example copper or copper with one or more additives such as lead, tin, manganese or silver), carbon/metal mixtures containing small quantities of other additives such as nonconducting abrasives and lubricants including molybdenum disulflde and P.T.F.E., i.e. polytetrafluoroethylene, through to metals containing only small amounts of carbon and/or other additives.
  • various metals or alloys for example copper or copper with one or more additives such as lead, tin, manganese or silver
  • carbon/metal mixtures containing small quantities of other additives such as nonconducting abrasives and lubricants including molybdenum disulflde and P.T.F.E., i.e. polytetrafluoroethylene
  • the main purpose of this invention is to overcome the problems encountered with brush designs wherein there is a weakness in the area of the junction between the body and the flexible conductor and particularly in the body portion immediately surrounding the junction. Therefore, whilst the invention might be applicable to almost all brushes, it is particularly concerned with brushes whose body construction is such that problems have been encountered in usage due to fracture near the junction of the body with the flexible conductor.
  • the metallic material of the layer sintered onto the body is chosen to have a greater tensile strength than the material of the body (which itself may contain a large proportion of metal), and the area of contact between the metallic layer and the body should be larger than the area of contact between the flexible conductor and the metallic layer, thereby effectively spreading the load over a relatively large area of the body if any jerks are applied to the flexible conductor.
  • the metallic layer effectively covers the face of the body of the brush opposite to the working (electrical contact) face.
  • FIG. I is a-side view of one embodiment of an electrical contact brush
  • FIG, 2 is a view, in cross section, of another embodiment of an electrical contact brush
  • FIGS. 3 7 illustrates varioussteps in the manufacture of an electrical contact brush.
  • an'electrical contact brush comprises a body 1 having attached thereto a metallic layer 2 to which is secured a flexible electrical conductor 3.
  • the brush body 1 is composedprimarily of a metal and graphite and the metal canbe, for example, copper together with alloyconstituents known in the art.
  • the metallic layer 2 can be composed of, for example, copper or iron, or a mixture thereof but the invention is not limited to the use of such metals.
  • the flexible conductor 3 may be formed from thin electrically conductive metal strands of, for example, copper. The strands can, of course, be formed from any other suitable metal.
  • the flexible electrical conductor 3 is attached to a surface of the metal layer 2 by welding.
  • the welded joint is indicated at 4. It is preferred that the welded joint is made by using a pressure-resistance welding technique.
  • the flexible conductor 3 is secured to the metal layer 2 by forming a bore in the layer 2 and thereafter securing one end of the flexible conductor within the bore by tamping with, for example, copper particles 6.
  • the flexible conductor 3 can, if desired, be placed in the bore and thereafter soldered to the metallic layer 2.
  • the brush body 1 is composed primarily of a metal and a graphite, and the metal may be copper with alloy constituents known in the art. Copper, or any other suitable metal can be present up to percent of the total brush composition.
  • a wide variety of materials may be used for the brush body, for example, compositions of metal and graphite in the range of from 25 percent copper, 75 percent graphite to 95 percent copper, 5 percent graphite, and the compositions may include lead, tin, zinc or a combination of these up to about 15 percent of the total composition so that, at the extreme, the brush composition may consist of 95 percent metal or alloy and 5 percent graphite. It will thus be realized that the actual brush materials themselves are not of prime importance but the present invention is particularly useful when it is necessary to attach a flexible copper conductor to a brush containing a major proportion of metal.
  • the surface area of contact between the metallic layer 2 and the brush body 1 is larger than that between the flexible conductor 3 and the metal layer 2.
  • the metallic layer 2 is formed and attached to the brush body 1 by cocompacting and cosintering the layer material together with the brush body material.
  • FIG. 3 represents a compaction press which includes a die 7 having a pair of reciprocal plungers 8 and 9.
  • Metallic powders to form the brush body 1 are placed in the die as shown in FIG. 4.
  • the bottom plunger 8 is then lowered by a specified amount.
  • Powders which constitute the metallic layer 2 are then put in the die 7 on top of the constituent powders of the brush body 1. This is shown in FIG. 6.
  • the top plunger 9 is then brought down to compress and so compact the powders together and the compacted constituents are then sintered at a suitable temperature for a suitable period of time.
  • stearic acid zinc steareate was also suitable as the die lubricant:
  • the mixture of powders was put into the die of a compaction pressand on to the top of this powder was placed a measured quantity of I00 mesh reduced sponge iron powder to form a layer of 5 mm. depth.
  • the powders were then cocompacted together at 10 tons per square inch pressure and were cosintered at 840 for 1 hour in a suitable protected atmosphere.
  • the powders forming the brush body 1 can be compressed before the powders constituting the metallic layer 2 are placed thereon. However, subsequent compaction does not provide a bond between the body and the layer as good as that of the first'mentioned process. Accordingly, the first process is preferred.
  • the cocompacting and cosintering processes provide an excellent physical and electrical bond between the brush body and the metal layer.
  • the joint between the flexible electrical conductor and the metallic layer whether it be made by welding, tamping or soldering, is physically strong since the attachment is made between two metals.
  • the surface area at the interface between the metallic layer and the brush body is larger than that between the flexible conductor and the layer' any tensile loading applied to the flexible conductor will be distributed evenly over the rush at said interface.
  • An electrical brush comprising a metal-and-carbon containing body, a metallic layer sintered with said body, said metallic layer comprising a metal other than any ingredient of said body, and electrical conductor means secured to said metallic layer and electrically connected therewith, said metallic layer having a greater tensile strength than that of said body.
  • metallic layer comprises copper.
  • An electrical brush according to claim 1 wherein said body is a composition essentially of copper and graphite in the range of from 25 percentcopper, percent graphite to percent copper, 5 percent graphite.
  • An electrical brush comprising a body of sintered metaland-carbon; a sintered metallic material layer, said metal-andcarbon of said body being cosintered with the metallic material of said layer, said metallic material layer comprising a metal other than any ingredient of said body; and electrical conductor means secured to said layer and electrically connected therewith, said layer having a greater tensile strength than said body.

Landscapes

  • Motor Or Generator Current Collectors (AREA)
US825305A 1968-05-23 1969-05-16 Electrical contact brushes Expired - Lifetime US3601645A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2463768 1968-05-23

Publications (1)

Publication Number Publication Date
US3601645A true US3601645A (en) 1971-08-24

Family

ID=10214872

Family Applications (1)

Application Number Title Priority Date Filing Date
US825305A Expired - Lifetime US3601645A (en) 1968-05-23 1969-05-16 Electrical contact brushes

Country Status (10)

Country Link
US (1) US3601645A (de)
JP (1) JPS5311641B1 (de)
AT (1) AT288535B (de)
BE (1) BE733581A (de)
DE (1) DE1926203A1 (de)
ES (1) ES367569A1 (de)
FR (1) FR2009196A1 (de)
GB (1) GB1259454A (de)
NL (1) NL6907728A (de)
SE (1) SE367735B (de)

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3786292A (en) * 1972-04-26 1974-01-15 Morganite Carbon Ltd An electrical contact brush assembly with anti-vibration head
US4101453A (en) * 1976-03-20 1978-07-18 Lucas Industries Limited Sintered composition
US4131460A (en) * 1976-03-20 1978-12-26 Lucas Industries Limited Method of producing a sintered composition
US4366361A (en) * 1976-04-09 1982-12-28 Lucas Industries Limited Method of producing an electrical component
US5152380A (en) * 1988-06-23 1992-10-06 Hoffmann & Co. Elektrokohle Gesellschaft Mbh Collector shoe for collector and process for producing it
US5214335A (en) * 1992-07-07 1993-05-25 General Motors Corporation Brush and slip ring apparatus for dynamoelectric machines
US5263562A (en) * 1988-06-23 1993-11-23 Hoffman & Co. Elektrokohle Gesellschaft M.B.H Carbon brush for collector
EP0627795A1 (de) * 1993-06-04 1994-12-07 Le Carbone Lorraine Vereinfachtes Verfahren zur Herstellung von Bürsten
US5447681A (en) * 1993-12-21 1995-09-05 Mando Corporation Method for manufacturing metal graphite brush
US5701046A (en) * 1993-09-02 1997-12-23 Le Carbone Lorraine Process for the production of multi-layered brushes and brushes obtained by the process
EP1003269A1 (de) * 1997-08-06 2000-05-24 Mitsuba Corporation Kohlekommutator und verfahren zu dessen herstellung
US6091051A (en) * 1996-12-28 2000-07-18 Minolta Co., Ltd. Heating device
US20030047032A1 (en) * 2001-06-22 2003-03-13 Newman Keith E. Method of producing powder metal parts from metallurgical powders including sponge iron
US20030094074A1 (en) * 2001-10-25 2003-05-22 Tris Inc. Metal-graphite brush
US20030141777A1 (en) * 2002-01-30 2003-07-31 Tris Inc. Copper-graphite brush
US20030190249A1 (en) * 2002-04-04 2003-10-09 Tris Inc. Metal-graphite brush and production method thereof
US20040174088A1 (en) * 2003-02-04 2004-09-09 Kyoji Inukai Multilayer brush
WO2005064756A1 (de) * 2003-12-19 2005-07-14 Hoffmann & Co. Elektrokohle Aktiengesellschaft Kohlebürste sowie verfahren und werkstoff zu ihrer herstellung
US20060087197A1 (en) * 2001-10-25 2006-04-27 Tris Inc. Metal-graphite brush
US20070042650A1 (en) * 2003-08-01 2007-02-22 Wilhelm Latz Sliding electrical contact part
US20090261687A1 (en) * 2006-02-08 2009-10-22 Schunk Kohlenstofftechnik Gmbh Method and device for manufacturing a multilayer compression moulded element
US7631206B2 (en) * 2006-02-10 2009-12-08 Intel Corporation Method and apparatus to support enhanced energy efficiency in a processing system
US20100133951A1 (en) * 2008-11-28 2010-06-03 Schunk Kohlenstofftechnik Gmbh Carbon brush for transmitting high currents
US20230006405A1 (en) * 2019-11-25 2023-01-05 Tris Inc. Metal graphite grounding brush mainly composed of silver and method for producing same

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2840372C3 (de) * 1978-09-16 1981-09-24 Deutsche Carbone Ag, 6000 Frankfurt Verfahren und Werkzeug zur Herstellung von Kohlebürsten
IT1164343B (it) * 1982-08-14 1987-04-08 Mtu Muenchen Gmbh Disposizione di componenti discreti, specialmente scambiatori di calore
GB9118968D0 (en) * 1991-09-04 1991-10-23 Morganite Elect Carbon Electrically conductive bonding of carbon to metal
EP1128496B1 (de) 2000-02-22 2008-12-10 Denso Corporation Verfahren zu Herstellung einer Mehrschicht-Bürste für eine rotierende elektrische Maschine
EP1507021A1 (de) * 2003-08-15 2005-02-16 Deutsche Carbone Ag Verfahren zum metallischen Beschichten von Graphitscheiben oder -blöcken sowie entsprechende Erzeugnisse
FR2972082B1 (fr) 2011-02-28 2013-03-29 Mersen France Amiens Sas Balai de contact

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US661669A (en) * 1898-07-22 1900-11-13 Gen Electric Connecting conductors to carbon brushes.
US764391A (en) * 1903-07-15 1904-07-05 Le Carbone Sa Electrical connection.
US1053881A (en) * 1911-09-21 1913-02-18 Campbell Scott Composition of matter.
US1067003A (en) * 1909-08-16 1913-07-08 Nat Carbon Co Process of making electrical conductors.
US1633815A (en) * 1925-09-14 1927-06-28 Gen Electric Electric terminal
US1708192A (en) * 1927-05-07 1929-04-09 Sherwood Charles Frederic Manufacture of bodies from metal powder
US1712477A (en) * 1926-05-03 1929-05-07 Globar Corp Electrical connection
US2092627A (en) * 1935-04-27 1937-09-07 Gen Electric Carbon brush
US2098062A (en) * 1935-04-26 1937-11-02 Gen Electric Carbon brush
US2319240A (en) * 1940-03-19 1943-05-18 Mallory & Co Inc P R Electric contact and the like
US2353047A (en) * 1942-04-04 1944-07-04 Carter Carburetor Corp Electric motor structure
US2989490A (en) * 1958-02-19 1961-06-20 Union Carbide Corp Electrical contact brush for high altitude use

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US661669A (en) * 1898-07-22 1900-11-13 Gen Electric Connecting conductors to carbon brushes.
US764391A (en) * 1903-07-15 1904-07-05 Le Carbone Sa Electrical connection.
US1067003A (en) * 1909-08-16 1913-07-08 Nat Carbon Co Process of making electrical conductors.
US1053881A (en) * 1911-09-21 1913-02-18 Campbell Scott Composition of matter.
US1633815A (en) * 1925-09-14 1927-06-28 Gen Electric Electric terminal
US1712477A (en) * 1926-05-03 1929-05-07 Globar Corp Electrical connection
US1708192A (en) * 1927-05-07 1929-04-09 Sherwood Charles Frederic Manufacture of bodies from metal powder
US2098062A (en) * 1935-04-26 1937-11-02 Gen Electric Carbon brush
US2092627A (en) * 1935-04-27 1937-09-07 Gen Electric Carbon brush
US2319240A (en) * 1940-03-19 1943-05-18 Mallory & Co Inc P R Electric contact and the like
US2353047A (en) * 1942-04-04 1944-07-04 Carter Carburetor Corp Electric motor structure
US2989490A (en) * 1958-02-19 1961-06-20 Union Carbide Corp Electrical contact brush for high altitude use

Cited By (41)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3786292A (en) * 1972-04-26 1974-01-15 Morganite Carbon Ltd An electrical contact brush assembly with anti-vibration head
US4101453A (en) * 1976-03-20 1978-07-18 Lucas Industries Limited Sintered composition
US4131460A (en) * 1976-03-20 1978-12-26 Lucas Industries Limited Method of producing a sintered composition
US4366361A (en) * 1976-04-09 1982-12-28 Lucas Industries Limited Method of producing an electrical component
US5263562A (en) * 1988-06-23 1993-11-23 Hoffman & Co. Elektrokohle Gesellschaft M.B.H Carbon brush for collector
US5152380A (en) * 1988-06-23 1992-10-06 Hoffmann & Co. Elektrokohle Gesellschaft Mbh Collector shoe for collector and process for producing it
US5214335A (en) * 1992-07-07 1993-05-25 General Motors Corporation Brush and slip ring apparatus for dynamoelectric machines
EP0627795A1 (de) * 1993-06-04 1994-12-07 Le Carbone Lorraine Vereinfachtes Verfahren zur Herstellung von Bürsten
FR2706089A1 (fr) * 1993-06-04 1994-12-09 Lorraine Carbone Procédé simplifié de fabrication de balais.
US5441683A (en) * 1993-06-04 1995-08-15 Le Carbone Lorraine Simplified process for the production of carbon motor brushes
TR28536A (tr) * 1993-06-04 1996-09-30 Lorraine Carbone Bir elektrik motorunun hareketli bölümleri (kolektörler) ile sabit bölümleri arasinda elektriksel temasi saglamaya yönelik fircalar.
CN1034842C (zh) * 1993-06-04 1997-05-07 洛林卡彭公司 制造电刷的简易方法
US5701046A (en) * 1993-09-02 1997-12-23 Le Carbone Lorraine Process for the production of multi-layered brushes and brushes obtained by the process
US5447681A (en) * 1993-12-21 1995-09-05 Mando Corporation Method for manufacturing metal graphite brush
US6091051A (en) * 1996-12-28 2000-07-18 Minolta Co., Ltd. Heating device
US6222298B1 (en) 1997-06-08 2001-04-24 Mitsuba Corporation Carbon commutator and method for producing the same
EP1003269A1 (de) * 1997-08-06 2000-05-24 Mitsuba Corporation Kohlekommutator und verfahren zu dessen herstellung
EP1003269A4 (de) * 1997-08-06 2002-03-20 Mitsuba Corp Kohlekommutator und verfahren zu dessen herstellung
US20030047032A1 (en) * 2001-06-22 2003-03-13 Newman Keith E. Method of producing powder metal parts from metallurgical powders including sponge iron
US20030094074A1 (en) * 2001-10-25 2003-05-22 Tris Inc. Metal-graphite brush
US20060087197A1 (en) * 2001-10-25 2006-04-27 Tris Inc. Metal-graphite brush
US7294166B2 (en) * 2001-10-25 2007-11-13 Tris Inc. Metal-graphite brush
US6755882B2 (en) * 2001-10-25 2004-06-29 Tris Inc. Metal-graphite brush
US20030141777A1 (en) * 2002-01-30 2003-07-31 Tris Inc. Copper-graphite brush
US7067951B2 (en) * 2002-01-30 2006-06-27 Tris Inc. Copper-graphite brush
US20030190249A1 (en) * 2002-04-04 2003-10-09 Tris Inc. Metal-graphite brush and production method thereof
US6758881B2 (en) * 2002-04-04 2004-07-06 Tris Inc. Metal-graphite brush and production method thereof
US20040174088A1 (en) * 2003-02-04 2004-09-09 Kyoji Inukai Multilayer brush
US6815862B2 (en) * 2003-02-04 2004-11-09 Denso Corporation Multilayer brush
US20070042650A1 (en) * 2003-08-01 2007-02-22 Wilhelm Latz Sliding electrical contact part
US7525232B2 (en) * 2003-08-01 2009-04-28 Carbone Larraine Applications Electriques Sliding electrical contact part
US20060260436A1 (en) * 2003-12-19 2006-11-23 Gerhard Bachauer Carbon brush and method and material for the production thereof
WO2005064756A1 (de) * 2003-12-19 2005-07-14 Hoffmann & Co. Elektrokohle Aktiengesellschaft Kohlebürste sowie verfahren und werkstoff zu ihrer herstellung
DE10359896A1 (de) * 2003-12-19 2005-07-21 Hoffmann & Co. Elektrokohle Ag Kohlebürste sowie Verfahren und Werkstoff zu ihrer Herstellung
US20090261687A1 (en) * 2006-02-08 2009-10-22 Schunk Kohlenstofftechnik Gmbh Method and device for manufacturing a multilayer compression moulded element
US8323548B2 (en) * 2006-02-08 2012-12-04 Schunk Kohlerstofftechnik GmbH Method for manufacturing a multilayer compression moulded element
US7631206B2 (en) * 2006-02-10 2009-12-08 Intel Corporation Method and apparatus to support enhanced energy efficiency in a processing system
US20100133951A1 (en) * 2008-11-28 2010-06-03 Schunk Kohlenstofftechnik Gmbh Carbon brush for transmitting high currents
US8847463B2 (en) 2008-11-28 2014-09-30 Schunk Kohlenstofftechnik Gmbh Carbon brush for transmitting high currents
US20230006405A1 (en) * 2019-11-25 2023-01-05 Tris Inc. Metal graphite grounding brush mainly composed of silver and method for producing same
US11764532B2 (en) * 2019-11-25 2023-09-19 Tris Inc. Metal graphite grounding brush mainly composed of silver and method for producing same

Also Published As

Publication number Publication date
DE1926203A1 (de) 1969-11-27
NL6907728A (de) 1969-11-25
SE367735B (de) 1974-06-04
AT288535B (de) 1971-03-10
ES367569A1 (es) 1971-04-01
FR2009196A1 (de) 1970-01-30
GB1259454A (de) 1972-01-05
BE733581A (de) 1969-11-24
JPS5311641B1 (de) 1978-04-24

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