US3788275A - Magnetic shielding apparatus - Google Patents

Magnetic shielding apparatus Download PDF

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Publication number
US3788275A
US3788275A US00266905A US3788275DA US3788275A US 3788275 A US3788275 A US 3788275A US 00266905 A US00266905 A US 00266905A US 3788275D A US3788275D A US 3788275DA US 3788275 A US3788275 A US 3788275A
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US
United States
Prior art keywords
magnetic
granules
shaft member
recited
bearing means
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
US00266905A
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English (en)
Inventor
W Hanson
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Xerox Corp
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Xerox Corp
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Filing date
Publication date
Application filed by Xerox Corp filed Critical Xerox Corp
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Publication of US3788275A publication Critical patent/US3788275A/en
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Expired - Lifetime legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J15/00—Sealings
    • F16J15/16—Sealings between relatively-moving surfaces
    • F16J15/40—Sealings between relatively-moving surfaces by means of fluid
    • F16J15/43—Sealings between relatively-moving surfaces by means of fluid kept in sealing position by magnetic force
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
    • F16C33/72—Sealings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
    • F16C33/72—Sealings
    • F16C33/76—Sealings of ball or roller bearings
    • F16C33/82—Arrangements for electrostatic or magnetic action against dust or other particles
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/09—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer using magnetic brush
    • G03G15/0942—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer using magnetic brush with means for preventing toner scattering from the magnetic brush, e.g. magnetic seals

Definitions

  • ABSTRACT A device in which a magnetic flux field forms a shield of magnetic granules about a shaft member journaled for rotary movement.
  • the shield is arranged to prevent contamination of the shaft member.
  • This invention relates generally to a development apparatus of an electrostatographic printing machine, and more particularly concerns a device for preventing contamination of the development apparatus.
  • an electrostatic charge pattern corresponding to an original document to be reproduced is recorded on an insulating medium.
  • a viewable record is produced by developing the electrostatic charge pattern with particles to form a powder image thereof. Thereafter, the visible powder image is fused to the insulating medium, or transferred to a suitable support material and fused thereto.
  • the electrostatic charge pattern or latent image is developed by bringing a developer mix into contact therewith.
  • developer mixes may be employed.
  • the developer mix comprises dyed or colored thermoplastic particles, known in the art as toner particles, which are mixed with coarser carrier granules, such as ferromagnetic granules.
  • the carrier granules charge the toner particles to the correct polarity by triboelectrification.
  • the electric field exerts a force on the charged toner particles. When this force is large enough to break the carrier-to-toner bond, the toner particles then attach themselves to the electrostatic latent image.
  • Impeller systems or conveyor systems generally include shaft members journaled for rotary movement in suitable rolling contact bearings, i.e., roller or ball bearings, to achieve the requisite movement of developer mix.
  • the dynamic load characteristics of the bearing generally determine its life expectancy. Defects in the bearings, mounting, lubrication, or contamination may accelerate failure and shorten bearing life. Magnetic carrier granules frequentlyenter the bearing and-act as a contaminant thereof. In this manner, the carrier granules contaminate the bearings supporting the shaft for rotary movement resulting in a reduction in the life expectancy thereof. This substantially reduces the life expectancy of the conveyor or impeller system and, in turn, that of the development apparatus.
  • a device arranged to prevent contamination of a shaft member journaled for rotary movement.
  • bearing means rotatably support the shaft member with magnetic means being interposed between the bearing means and a flow of magnetic granules.
  • a magnetic flux field produced by the magnetic means entraps and aligns the magnetic granules into a shield.
  • the shield of granules located between the shaft member and the magnetic means prevents subsequent granules from contaminating the bearing means.
  • the present invention also includes means for impelling the granules entrapped by the shield in a direction substantially away from the bearing means.
  • FIG. 1 is a sectional elevational view of a development apparatus having the present invention therein and adapted for usage in an electrostatographic printing machine;
  • FIG. 2 is a partial, fragmentary sectional view of the shielding device used in the development apparatus depicted in FIG. 1.
  • FIG. 1 schematically illustrates the development apparatus used in an electrostatographic printing machine for producing copies from an original document.
  • an electrostatic latent image is formed on an insulating medium. Developer mix is brought into contact with the latent image and toner particles deposited thereon to form a powder image thereof. Thereafter, the powder image is transferred to a sheet of support material to which it may be permanently adhered by a suitable fusing device.
  • This concept was originally disclosed in US. Pat. No. 2,297,691 issued to Carlson in 1942.
  • the development unit depicted in FIG. 1 is of the type referred to in the art as a magnetic brush development system."
  • a magnetic brush development system a magnetizable developer mix having carrier granules and toner particles is continually moved through a directional flux field to form a brush of developer material.
  • the brush comprises a magnetic member with a mass of developer mix adhering thereto by magnetic attraction. This chain-like arrangement of developer mix simulates the fibers of a brush. Development is achieved by bringing the brush of developer mix into contact with the electrostatic latent image.
  • Paddle wheel 12 is a cylindrical member with scoops or buckets 20 mounted around the periphery thereof. As paddle wheel 12 rotates, it elevates developer mix 18 from the lower region or sump of housing 10 to the upper region thereof. When developer mix 18 reaches the upper region of housing 10, it is lifted from buckets 20 to transport roll 14 by the magnetic flux field produced by fixed magnets 22 disposed interiorly thereto.
  • alternate buckets 20 of paddle wheel 12 have apertures in the root diameters thereof enabling developer mix 18 carried in those areas to fall back to the sump of developer housing 10.
  • shroud 24 which is preferably a tubular member having an aperture or longitudinally extending slot 26 in the lower region thereof.
  • developer mix 18 is recirculated such that the carrier granules thereof are continually agitated to mix with fresh toner particles and generate a strong triboelectric charge therebetween.
  • Transport roll 14 moves developer mix 18 in an upwardly direction by the frictional force exerted between the roll surface and developer mix 18.
  • Metering blade 28 is provided to control the amount of developer mix 18 carried over the top of transport roll 14. The surplus developer mix is sheared from transport roll 14 and falls in a downwardly direction toward paddle wheel 12. Surplus developer mix falls through the apertures of paddle wheel 12 in a downwardly direction into the sump of developer housing 10.
  • Developer mix 18 which passes metering blade 28, is carried over transport roll 14 to developer roll 16 and into development zone 30 located between photoconductive surface 32 of drum 34 and developer roll 16.
  • the electrostatic latent image recorded on photoconductive surface 32 is developed by contact with moving developer mix 18.
  • the charged areas of photoconductive surface 32 electrostatically attract toner particles from the carrier granules of developer mix 18.
  • magnetic fields in a direction generally tangential to developer roll 16 continue to secure thereto denuded carrier granules (carrier granules which had toner particles stripped therefrom) and unused developer mix.
  • Paddle wheel 12 Upon passing from development zone 30, the denuded carrier granules and unused developer mix enter a region relatively free from magnetic forces and fall from developer roll 16 in a downwardly direction into the lower region of developer housing 10. As the denuded carrier granules and unused developer mix descend, mixing baffle 36 diverts the flow from the ends toward the center of developer housing to provide mixing in this direction.
  • Paddle wheel 12 includes a shaft member or hub 38 rotatably mounted on frame member or developer housing 18. Buckets are secured fixedly to hub member 38.
  • Cylindrical shroud 24 serves to control the fall of unused developer mix and denuded carrier granules such that they mix with toner particles rather than simply falling into the sump of developer housing 10. Furthermore, shroud 24 isolates, from developer mix 18, an interior cylindrical enclosure which is used to house toner dispenser 40. Toner dispenser 40 contains a fresh supply of toner particles 42 arranged to pass through slot 26 in shroud 24 and into the stream of developer mix 18. Having toner particles introduced into the developer mix at this location insures that the particles cannot be carried into development zone without some degree of mixing with the carrier granules. Additional toner particles are added to developer mix 18 in order to replace the particles used in forming images so as to maintain the concentration thereof substnatially constant providing substantially uniform image developability.
  • Development begins when clutch gear 44 meshes with gear 46 which is secured to paddle wheel 12.
  • Clutch gear 44 rotates in the direction of arrow 48 to drive gear 46 in the direction of arrow 50, thereby causing paddle wheel 12 to also revolve in the direction of arrow 58.
  • the development unit positions developer roll 16 adjacent the photoconductive surface 32 in operative communication therewith to develop the electrostatic latent image formed thereon with toner particles. Thereafter, toner particles are transferred to the support material forming a toner powder image of the original document thereon.
  • development roll 16 includes stationary magnets 52 disposed interiorly and arranged to attract developer mix 18 thereto from transport roll 14.
  • paddle wheel 12 is journaled for rotary movement by suitable bearing means such as roller bearings or ball bearings mounted on opposed end portions of hub member 38 providing support therefore.
  • bearing means such as roller bearings or ball bearings mounted on opposed end portions of hub member 38 providing support therefore.
  • Carrier granules may contaminate the bearing member and reduce the life expectancy of the paddle wheel assembly.
  • magnetic means are mounted on shroud 24 and developer housing 10. The aforementioned relation ship between the magnetic means and bearing means is indicated more clearly in FIG. 2.
  • developer housing 10 includes a generally cylindrical interior surface for housing roller bearing 54.
  • Outer race 56 of roller bearing 54 is mounted on the cylindrical interior surface of developer housing 10, while inner race 58 of bearing 54 is mounted on hub member 38 of paddle wheel 12.
  • a pair of such bearing members are mounted on hub member 38 in the region of opposed end portions to provide a simple support therefore.
  • paddle wheel 12 is journaled for rotary movement to raise developer mix 18 from the lower region of developer housing 10 to the upper region thereof.
  • paddle wheel 10 is interposed between shroud 24 and developer housing 10 and is substantially concentric about the longitudinal axis of shroud 24.
  • end cap 60 is removably mounted on developer housing 10.
  • Magnetic means or ring magnet 62 has the exterior circumferential surface thereof mounted on developer housing 10 and is spaced axially from bearing member 54 by arcuate spacer 64. The interior circumferential surface of magnetic means 62 is spaced from hub member 38.
  • Hub member 38 includes a threaded portion 66 aligned so as to be opposed from magnetic means 62.
  • threaded portion 66 may be a suit able pipe thread.
  • carrier granules 68 advance toward bearing member 54 they are attracted to mag netic means or ring magnet 62 via the magnetic flux field formed thereby.
  • the magnetic flux field is arranged to form a shield of carrier granules between hub member 38 and ring magnet 62.
  • hub member 38 rotates the exterior threaded portion 66 thereof is arranged to impel carrier granules 68 in a direction substantially away from bearing member 54.
  • an interior magnetic member 72 is mounted on shroud 24 in operative communication with internal threaded portion 74 e.g., a suitable pipe thread, of hub member 38.
  • the magnetic means or ring magnet 72 has the interior circumferential surface thereof mounted on shroud 24.
  • the exterior circumferential surface of ring magnet 72 is spaced from hub member 38.
  • the interior threaded portion 74 of the hub member 38 is spaced from and aligned with the exterior circumferential surface of ring magnet 72.
  • Ring magnet 72 is arranged to form a magnetic flux field which aligns and entraps carrier granules 68 to form shield 71 between the interior circumferential surface of hub member 38 and ring magnet 72.
  • Hub member 38 includes an interior threaded portion 74 substantially aligned with the exterior circumferential surface of ring member 72. Threaded portion 74 is adapted to impel carrier granules 68 away from bearing member 54 as hub member 38 rotates.
  • the shielding arrangement of the present device substantially improves the development apparatus of an electrostatographic printing machine by reducing contamination thereof. Furthermore, the carrier granules are prevented from entering the bearing members supporting the paddle wheel in rotary movement, thereby improving its life expectancy.
  • a device for preventing magnetic granules from contaminating a tubular shaft member joumaled for rotary movement including:
  • each said magnetic means being interposed between said bearing means and the flow of magnetic granules, said magnetic means producing a magnetic flux field entrapping and aligning the granules into a shield located between the shaft member and said magnetic means to prevent granules from contaminating said bearing means.
  • a device as recited in claim 2 further including a frame member adapted to support said bearing means so as to enable the shaft member to rotate relative thereto.
  • said magnetic means includes a magnet member mounted on the shaft member spaced from said frame member.
  • said impelling means includes a threaded portion on said frame member aligned generally opposed from said magnetic member and spaced therefrom, said threaded portion being adapted to move the entrapped granules in a direction substantially away from said bearing means as the shaft member rotates.
  • said magnetic means includes a magnet member mounted on said frame member spaced from the shaft member.
  • said impelling means includes a threaded portion on the shaft member aligned generally opposed from said magnet member and spaced therefrom, said threaded portion being adapted to move the entrapped granules in a direction substantially away from said bearing means as the shaft member rotates.
  • a development apparatus for an electrostatographic printing machine of the type having conveyor means for transporting a developer mix comprising magnetic carrier granules and toner particles into contact with an electrostatic latent image to create a toner powder image thereof, wherein the improvement includes:
  • each said magnetic means being interposed between said bearing means and the flow of carrier granules, said magnetic means producing a magnetic flux field entrapping and aligning the carrier granules into a shield located between said shaft member and said magnetic means to prevent granules from contaminating said bearing means.
  • An apparatus as recited in claim 8 further including means for impelling the granules entrapped by the shield formed by said magnetic means in a direction substantially away from said bearing means.
  • said magnetic means includes a magnet member mounted on said shaft member spaced from said frame member.
  • said impelling means includes a threaded portion on said frame member aligned generally opposed from said magnetic member and spaced therefrom, said threaded portion being adopted to move the entrapped granules in a direction substantially away from said bearing means as said shaft member rotates.
  • said magnetic means includes a magnetic member mounted on said frame member spaced from said shaft member.
  • said impelling means includes a threaded portion on said shaft member aligned generally opposed from said magnetic member and spaced therefrom said threaded portion being adapted to move the entrapped granules in a direction substantially away from said bearing means as said shaft member rotates.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Dry Development In Electrophotography (AREA)
  • Sealing Devices (AREA)
  • Magnetic Brush Developing In Electrophotography (AREA)
  • Sealing Of Bearings (AREA)
  • Magnetic Bearings And Hydrostatic Bearings (AREA)
US00266905A 1972-06-28 1972-06-28 Magnetic shielding apparatus Expired - Lifetime US3788275A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US26690572A 1972-06-28 1972-06-28

Publications (1)

Publication Number Publication Date
US3788275A true US3788275A (en) 1974-01-29

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Family Applications (1)

Application Number Title Priority Date Filing Date
US00266905A Expired - Lifetime US3788275A (en) 1972-06-28 1972-06-28 Magnetic shielding apparatus

Country Status (9)

Country Link
US (1) US3788275A (de)
JP (1) JPS5632628B2 (de)
BE (1) BE801242A (de)
CA (1) CA973703A (de)
DE (1) DE2255978A1 (de)
FR (1) FR2191166B1 (de)
GB (2) GB1438331A (de)
IT (1) IT990692B (de)
NL (1) NL7308988A (de)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3991713A (en) * 1974-02-20 1976-11-16 Xerox Corporation Development apparatus for an electrostatographic printing machine
US3998184A (en) * 1975-03-20 1976-12-21 Xerox Corporation Development apparatus
US4008686A (en) * 1974-05-21 1977-02-22 Konishiroku Photo Industry Co., Ltd. Developing device for use in electrophotography
US4026242A (en) * 1974-06-28 1977-05-31 Grafosol S.P.A. Matrix supporting device in electrostatic development apparatus
US4041903A (en) * 1974-05-21 1977-08-16 Konishiroku Photo Industry Co., Ltd. Developing device for use in electrophotography
US4580888A (en) * 1983-06-08 1986-04-08 Xerox Corporation Electrostatographic development apparatus
US4596455A (en) * 1983-09-20 1986-06-24 Kabushiki Kaisha Toshiba Developing apparatus
US4948152A (en) * 1988-02-17 1990-08-14 Firma Carl Freudenberg Shaft seal
GB2244762A (en) * 1990-06-08 1991-12-11 Xerox Corp Bearing assembly with magnetic seal
US5177536A (en) * 1989-03-31 1993-01-05 Canon Kabushiki Kaisha Developing apparatus having a magnetic seal
US5267007A (en) * 1989-08-04 1993-11-30 Canon Kk Magnetic seal for preventing developer from leaking out of the longitudinal ends of a rotatable member
US5267003A (en) * 1992-08-11 1993-11-30 Olivetti Supplies, Inc. Toner cartridge refilling seal using magnetic material
US5287148A (en) * 1990-07-10 1994-02-15 Canon Kabushiki Kaisha Magnetic seal for a developing apparatus
US5315354A (en) * 1993-04-23 1994-05-24 Xerox Corporation Carrier bead seal
US5442423A (en) * 1994-06-23 1995-08-15 Xerox Corporation External development housing bearings
US5450169A (en) * 1994-06-23 1995-09-12 Xerox Corporation Multi-lobe magnetic seals
EP0723211A2 (de) 1995-01-17 1996-07-24 Xerox Corporation Magnetische Abdichtung für Entwicklungsgerät
US20060125191A1 (en) * 2004-12-15 2006-06-15 William Kordonski Method and apparatus for forming a dynamic magnetic seal using magnetorheological fluid
US11081928B2 (en) 2016-08-23 2021-08-03 Lord Corporation Magnetic seal for magnetically-responsive devices, systems, and methods

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5815791B2 (ja) * 1975-04-07 1983-03-28 株式会社ケイアイピ− デンシフクシヤキニオケルゲンゾウソウチ
JPS5364525A (en) * 1976-11-22 1978-06-09 Fuji Xerox Co Ltd Magnetic brush developing device of electrostatic copying machine
JPS54103043A (en) * 1978-01-31 1979-08-14 Nippon Telegr & Teleph Corp <Ntt> Developer
JPS6312352Y2 (de) * 1980-02-26 1988-04-08
JPS6237241Y2 (de) * 1980-04-02 1987-09-22
JPS5829479Y2 (ja) * 1980-05-30 1983-06-28 東京航空計器株式会社 現像剤容器内回転体の軸受部の構造
GB2141049B (en) * 1983-06-08 1986-07-23 Xerox Corp Electrostatographic development apparatus
US4843421A (en) * 1988-06-24 1989-06-27 Xerox Corporation System for priming the magnetic brush end seals of copier/printer machines

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2809733A (en) * 1952-10-29 1957-10-15 Texas Instruments Inc Magnetic fluid seals in magnetic clutches
US2863538A (en) * 1954-10-22 1958-12-09 Eaton Mfg Co Permanent magnet seal
US2944843A (en) * 1957-08-08 1960-07-12 Magnetic Seal Corp Spring loaded seal
US2996162A (en) * 1958-04-07 1961-08-15 Henry C Lehde Devices for excluding magnetic particles from seals and bearings
US3254745A (en) * 1963-01-21 1966-06-07 Isakov Vladimir Olimpijevich Seal to protect the bearings of powder magnetic clutches or of similar devices against the ferromagnetic powder

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE792643A (fr) * 1971-12-17 1973-03-30 Ibm Dispositif de developpement electrophotographique

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2809733A (en) * 1952-10-29 1957-10-15 Texas Instruments Inc Magnetic fluid seals in magnetic clutches
US2863538A (en) * 1954-10-22 1958-12-09 Eaton Mfg Co Permanent magnet seal
US2944843A (en) * 1957-08-08 1960-07-12 Magnetic Seal Corp Spring loaded seal
US2996162A (en) * 1958-04-07 1961-08-15 Henry C Lehde Devices for excluding magnetic particles from seals and bearings
US3254745A (en) * 1963-01-21 1966-06-07 Isakov Vladimir Olimpijevich Seal to protect the bearings of powder magnetic clutches or of similar devices against the ferromagnetic powder

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3991713A (en) * 1974-02-20 1976-11-16 Xerox Corporation Development apparatus for an electrostatographic printing machine
US4008686A (en) * 1974-05-21 1977-02-22 Konishiroku Photo Industry Co., Ltd. Developing device for use in electrophotography
US4041903A (en) * 1974-05-21 1977-08-16 Konishiroku Photo Industry Co., Ltd. Developing device for use in electrophotography
US4026242A (en) * 1974-06-28 1977-05-31 Grafosol S.P.A. Matrix supporting device in electrostatic development apparatus
US3998184A (en) * 1975-03-20 1976-12-21 Xerox Corporation Development apparatus
US4580888A (en) * 1983-06-08 1986-04-08 Xerox Corporation Electrostatographic development apparatus
US4596455A (en) * 1983-09-20 1986-06-24 Kabushiki Kaisha Toshiba Developing apparatus
US4948152A (en) * 1988-02-17 1990-08-14 Firma Carl Freudenberg Shaft seal
US5177536A (en) * 1989-03-31 1993-01-05 Canon Kabushiki Kaisha Developing apparatus having a magnetic seal
US5267007A (en) * 1989-08-04 1993-11-30 Canon Kk Magnetic seal for preventing developer from leaking out of the longitudinal ends of a rotatable member
GB2244762A (en) * 1990-06-08 1991-12-11 Xerox Corp Bearing assembly with magnetic seal
GB2244762B (en) * 1990-06-08 1994-06-08 Xerox Corp Bearing assembly for a rotatable member
US5287148A (en) * 1990-07-10 1994-02-15 Canon Kabushiki Kaisha Magnetic seal for a developing apparatus
US5267003A (en) * 1992-08-11 1993-11-30 Olivetti Supplies, Inc. Toner cartridge refilling seal using magnetic material
US5315354A (en) * 1993-04-23 1994-05-24 Xerox Corporation Carrier bead seal
US5450169A (en) * 1994-06-23 1995-09-12 Xerox Corporation Multi-lobe magnetic seals
US5442423A (en) * 1994-06-23 1995-08-15 Xerox Corporation External development housing bearings
EP0723211A2 (de) 1995-01-17 1996-07-24 Xerox Corporation Magnetische Abdichtung für Entwicklungsgerät
US5552864A (en) * 1995-01-17 1996-09-03 Xerox Corporation Magnetic seal with tapered shunts
US20060125191A1 (en) * 2004-12-15 2006-06-15 William Kordonski Method and apparatus for forming a dynamic magnetic seal using magnetorheological fluid
US7156724B2 (en) * 2004-12-15 2007-01-02 Qed Technologies International, Inc. Method and apparatus for forming a dynamic magnetic seal using magnetorheological fluid
US11081928B2 (en) 2016-08-23 2021-08-03 Lord Corporation Magnetic seal for magnetically-responsive devices, systems, and methods
US11095184B2 (en) 2016-08-23 2021-08-17 Lord Corporation Magnetic seal for magnetically-responsive devices, systems, and methods

Also Published As

Publication number Publication date
DE2255978A1 (de) 1974-01-10
NL7308988A (de) 1974-01-02
BE801242A (fr) 1973-12-21
GB1438331A (en) 1976-06-03
JPS4953444A (de) 1974-05-24
GB1438332A (en) 1976-06-03
FR2191166A1 (de) 1974-02-01
CA973703A (en) 1975-09-02
JPS5632628B2 (de) 1981-07-29
IT990692B (it) 1975-07-10
FR2191166B1 (de) 1977-05-13

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