US20020128137A1 - Magnetic roll for use in xerographic printing, and method of making thereof - Google Patents
Magnetic roll for use in xerographic printing, and method of making thereof Download PDFInfo
- Publication number
- US20020128137A1 US20020128137A1 US10/145,466 US14546602A US2002128137A1 US 20020128137 A1 US20020128137 A1 US 20020128137A1 US 14546602 A US14546602 A US 14546602A US 2002128137 A1 US2002128137 A1 US 2002128137A1
- Authority
- US
- United States
- Prior art keywords
- partial
- cylindrical surface
- partial cylinder
- cylinder
- magnetic
- 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.)
- Abandoned
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Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F7/00—Magnets
- H01F7/02—Permanent magnets [PM]
- H01F7/0231—Magnetic circuits with PM for power or force generation
- H01F7/0252—PM holding devices
- H01F7/0268—Magnetic cylinders
-
- 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
- G03G15/0921—Details concerning the magnetic brush roller structure, e.g. magnet configuration
-
- 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
- Y10T29/49544—Roller making
Definitions
- each partial cylinder 12 , 14 Because it is possible to design each partial cylinder 12 , 14 , to have the same profile along the entire length thereof, it is also conceivable to manufacture each partial cylinder 12 , 14 by an extrusion process.
- an extrusion die (not shown) for making a partial cylinder can be considered a form of “mold.”
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- General Physics & Mathematics (AREA)
- Magnetic Brush Developing In Electrophotography (AREA)
Abstract
A magnetic roll, such as for use in a xerographic printing apparatus, is formed from two semicylindrical partial cylinders. The partial cylinders can be molded and attached to each other to form a complete cylinder defining magnetic poles along the circumference thereof.
Description
- This is a divisional of application Ser. No. 09/503,835; filed Feb. 15, 2000.
- The present invention relates to the construction of a magnetic roll for use in a processing station of an electrostatographic printing machine.
- In the well-known process of electrostatographic printing, which includes xerographic printing and copying, a charge-receptive member is initially uniformly charged, and portions of the member are discharged according to an image desired to be printed. The imagewise-discharged areas form an electrostatic latent image. This latent image is subsequently developed by applying a fine toner to the charge-receptive member, the toner adhering to those areas of the latent image which are charged in a particular way. The developed image is then transferred to a sheet, yielding a print of a desired image. Following transfer, any remaining toner on the charge-receptive member is cleaned from the charge-receptive member.
- In many common designs of electrostatographic printing machines, magnetic rolls are employed in the developing station and the cleaning station. Typically, the magnetic roll includes a stationary magnet having a rotating tube or sleeve positioned concentrically thereabout. The magnetic roll defines a series of longitudinal magnetic poles arranged in alternating fashion around the circumference thereof. When the sleeve is rotated around the stationary magnetic roll, developer material (which typically includes toner and a magnetically-permeable carrier) is held by the magnetic poles to the sleeve and conveyed on the surface of the sleeve toward the charge-receptive member.
- The present invention is directed toward the construction of a magnetic roll for use in an electrostatographic printer.
- In the prior art, U.S. Pat. No. 4,638,281 discloses a magnetic roll which includes a central carrier, in the form of a cylinder having a set of strip-shaped cavities along longitudes thereof. Permanent magnetic components are placed in the strip-shaped cavities.
- U.S. Pat. No. 4,823,102 discloses a magnetic roll having a central portion with a plurality of spaced fins extending radially therefrom. A magnet is secured in each space between adjacent fins.
- U.S. Pat. No. 5,570,167 discloses a technique for molding a magnetic roll. A molten resin containing magnetic particles is injected into a mold cavity, while magnetic lines of force are applied.
- U.S. Pat. No. 5,740,509 discloses a magnetic roll including a columnar magnet with a D-shaped central bore. The D-shaped bore causes one portion of the magnet to have a particularly strong magnetic pole relative to other magnetic poles along the circumference.
- U.S. Pat. No. 5,894,004 discloses a mold for manufacturing a magnetic roll. The mold includes a body and an insert, which are used to provide specific configurations of magnetic poles in the finished roller.
- According to one aspect of the present invention, there is provided a method of making a magnetic roll suitable for use in developing an electrostatic latent image. A first partial cylinder is provided, defining a first partial cylindrical surface. A second partial cylinder is provided, defining a second partial cylindrical surface. The first partial cylinder is attached to the second partial cylinder, thereby combining the first partial cylindrical surface with the second partial cylindrical surface. At least one magnetic pole is defined in a portion of the combined first partial cylindrical surface and second partial cylindrical surface.
- According to another aspect of the present invention, there is provided a magnetic roll suitable for use in developing an electrostatic latent image. A first partial cylinder, defining a first partial cylindrical surface, is attached to a second partial cylinder, defining a second partial cylindrical surface, to yield a combined cylindrical surface. At least one magnetic pole is defined in a portion of the combined cylindrical surface.
- FIG. 1 is a sectional, elevational, exploded view of the partial cylinders of a magnetic roll according to the present invention;
- FIG. 2 is a perspective view showing, in isolation, one partial cylinder of a magnetic roll according to the present invention;
- FIG. 3 is a perspective view showing a portion of a magnetic roll according to the present invention;
- FIG. 4 is a sectional elevational view of a prior art magnetic roll;
- FIG. 5 is a simplified sectional elevational view showing the magnetic roll of the present invention and the context of an electro-photographic printer;
- FIG. 6 is a simplified sectional elevational view showing the creation of a partial cylinder of a magnetic roll according to the present invention by molding; and
- FIG. 7 is a sectional, elevational view of an embodiment of a magnetic roller according to the present invention.
- FIG. 1 is a sectional elevational view showing, in exploded form, the essential portions of a magnetic roll made according to the present invention. As is well known, a magnetic roll is typically in the form of a cylinder, and in the sectional view of FIG. 1, a
magnetic roll 10 comprises two partial cylinders, labeled respectively 12 and 14. Eachpartial cylinder partial cylinders - As is known in the art of magnetic rolls for electrostatographic printing, a preferred material for the
partial cylinders magnetic roll 10 is a moldable, curable resin in which magnetically-permeable particles are suspended. Either during or after the molding of the resin to formpartial cylinders partial cylinders magnetic roll 10 will depend on the requirements of a particular printing apparatus. Nonetheless, it is typically preferred, if not inevitable, that magnetic poles alter in polarity along the circumference of amagnetic roll 10 when thepartial cylinders - FIG. 2 is a perspective view, showing, in isolation, one partial cylinder of12 of the
magnetic roll 10 shown in FIG. 1. As can be seen, thepartial cylinder 12, which is preferably a single piece of cured resin, is shaped to accommodate semicircular-shaped end caps - FIG. 3 is a perspective view showing an assembled
magnetic roll 10, each end of which is formed by complementarysemicircular end caps end cap partial cylinder end caps magnetic roll 10. The twopartial cylinders end caps - FIG. 4 is an elevational view of a prior art
magnetic roll 9, which is formed from a single molded piece of resin, in which the magnetically-permeable particles suspended in the resin form a series of alternating poles around the circumference as shown. This prior-artmagnetic roll 9, because it is formed from a single molded piece, must be designed to accommodate the opening and closing of the mold from which it was made, and therefore, this design is capable only of having an effective circumference of 270°. - FIG. 5 is a simplified sectional elevational view showing some essential elements of a xerographic printer in which a
magnetic roll 10 of the present invention may be used. As shown, themagnetic roll 10, according to the present invention, is disposed within a rotatingsleeve 30 which is adjacent a rotating drum-type charge-retentive member (photoreceptor) 32, as is typically found in xerographic printing apparatus. Themagnetic roll 10 andsleeve 30 are in turn disposed within adeveloper housing 34, of any design known in the art, which typically includes at least one auger such as 36. In this way, developer material, typically including toner particles and a magnetically-permeable carrier, is stirred byauger 36 and conveyed along the moving surface ofsleeve 30 to develop a latent image on charge-receptive member 32. According to a preferred embodiment of the present invention, the poles on the assembledmagnetic roll 10 should be disposed around the circumference ofmagnetic roll 10 so that one pole of a first polarity disposed in one partial cylinder is adjacent a second pole of an opposite polarity in the other partial cylinder. Even more preferably, there is a “crossover point” of radial or tangential magnetic poles (i.e., a location along the circumference where the magnetic flux is very low or zero) at each interface wherepartial cylinders - FIG. 6 is a simplified sectional elevational view of a
mold 50, comprising atop portion 52 andlower portion 54, which together form a void at the interface thereof, this void having the negative shape corresponding to a cylindrical surface of a partial cylinder such as 12 of the magnetic roll according to the present invention. (There may or may not exist separate molds for eachpartial cylinder injection tube 56, for pouring liquid resin into the void 12′, in a manner known in the art of injection molding: indeed, it may be more preferable to have thetube 56 disposed at one end of the void 12′. - Also shown in FIG. 6 are a set of
electromagnets 60, which, according to one possible embodiment of a method according to the present invention, may be disposed within aportion 54 ofmold 50. Theelectromagnets 60 are disposed to exert magnetic flux along specific longitudes in the outer surface of apartial cylinder 12 being created within the void 12′, similar to any number of methods known in the art. The magnetic flux created byelectromagnets 60 imparts permanent magnetic poles at discrete locations in the partial cylinder, either as the resin therein is cured or thereafter. Theelectromagnets 60 are connected to one or more power supplies such as 62. - As can be seen from FIG. 6, the semi-circular shape of partial cylinders such as12 or 14 forming a particular
magnetic roll 10 is readily conducive to injection molding. Unlike the prior art magnet in FIG. 4, by providing two suchpartial cylinders magnetic roll 10 of the present invention can exhibit magnetic polarity around its entire circumference, as opposed to the partial circumference of the prior art magnetic roll of FIG. 4. - Because it is possible to design each
partial cylinder partial cylinder - According to the present invention, it is also conceivable to create a magnetic roll from more than the two complementary
partial cylinders partial cylinder 14 cover only 90° of the circumference. While it is probably easier to providepartial cylinders magnetic roll 10. - It is also possible, according to the present invention, to cause magnetic poles to be formed in the partial cylinders by other means that the magnetization technique shown above. For instance, one could provide specially-shaped voids on the inner, concave surfaces of partial cylinders such as12 and 14, and place discrete magnetic members in the voids, to result in the desired magnetic properties along the circumference of the magnetic roll. FIG. 7 shows an embodiment of a
roller 10 according to the present invention, in which discrete, strip-shaped magnets such as 26, 28 are disposed within shaped voids on the interior of eachpartial cylinder
Claims (12)
1. A method of making a magnetic roll suitable for use in developing an electrostatic latent image, comprising the steps of:
providing a first partial cylinder, the first partial cylinder defining a first partial cylindrical surface;
providing a second partial cylinder, the second partial cylinder defining a second partial cylindrical surface;
attaching the first partial cylinder to the second partial cylinder, thereby combining the first partial cylindrical surface with the second partial cylindrical surface; and
imparting at least one magnetic pole to a portion of the combined first partial cylindrical surface and second partial cylindrical surface.
2. The method of claim 1 , wherein the combined first partial cylindrical surface and second partial cylindrical surface form a complete cylindrical surface.
3. The method of claim 1 , wherein the first partial cylindrical surface and second partial cylindrical surface each define one-half of a cylindrical surface.
4. The method of claim 1 , wherein the step of providing a first partial cylinder includes inserting a quantity of magnetically-permeable, curable material into a mold, the mold defining a negative partial cylindrical surface.
5. The method of claim 4 , wherein the inserting step includes extruding the magnetically-permeable material.
6. The method of claim 4 , wherein the step of imparting at least one magnetic pole includes magnetizing the magnetically-permeable, curable material at a predetermined location of the first cylindrical surface.
7. The method of claim 1 , wherein the step of imparting at least one magnetic pole includes the steps of
imparting a first magnetic pole of a first polarity at a predetermined location in the first partial cylinder;
imparting a second magnetic pole of a second polarity opposite the first polarity at a predetermined location in the second partial cylinder; and
attaching the first partial cylinder to the second partial cylinder so that the first magnetic pole is immediately adjacent the second magnetic pole.
8. A magnetic roll suitable for use in developing an electrostatic latent image, comprising:
a first partial cylinder, the first partial cylinder defining a first partial cylindrical surface;
a second partial cylinder, the second partial cylinder defining a second partial cylindrical surface;
the first partial cylinder being attached to the second partial cylinder, to yield a combined cylindrical surface; and
at least one magnetic pole defined in a partial cylinder of the combined cylindrical surface.
9. The roll of claim 8 , wherein the combined first partial cylindrical surface and second partial cylindrical surface form a complete cylindrical surface.
10. The roll of claim 8 , wherein the first partial cylindrical surface and second partial cylindrical surface each define one-half of a cylindrical surface.
11. The roll of claim 8 , wherein a first magnetic pole of a first polarity is defined at a predetermined location in the first partial cylinder;
a second magnetic pole of a second polarity opposite the first polarity is defined at a predetermined location in the second partial cylinder; and
the first partial cylinder is attached to the second partial cylinder so that the first magnetic pole is adjacent the second magnetic pole.
12. The roll of claim 8 , further comprising at least one discrete magnetic member disposed within the combined cylindrical surface.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/145,466 US20020128137A1 (en) | 2000-02-15 | 2002-05-13 | Magnetic roll for use in xerographic printing, and method of making thereof |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/503,835 US6422984B1 (en) | 2000-02-15 | 2000-02-15 | Magnetic roll for use in xerographic printing |
US10/145,466 US20020128137A1 (en) | 2000-02-15 | 2002-05-13 | Magnetic roll for use in xerographic printing, and method of making thereof |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/503,835 Division US6422984B1 (en) | 2000-02-15 | 2000-02-15 | Magnetic roll for use in xerographic printing |
Publications (1)
Publication Number | Publication Date |
---|---|
US20020128137A1 true US20020128137A1 (en) | 2002-09-12 |
Family
ID=24003716
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/503,835 Expired - Lifetime US6422984B1 (en) | 2000-02-15 | 2000-02-15 | Magnetic roll for use in xerographic printing |
US10/145,466 Abandoned US20020128137A1 (en) | 2000-02-15 | 2002-05-13 | Magnetic roll for use in xerographic printing, and method of making thereof |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/503,835 Expired - Lifetime US6422984B1 (en) | 2000-02-15 | 2000-02-15 | Magnetic roll for use in xerographic printing |
Country Status (1)
Country | Link |
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US (2) | US6422984B1 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080298849A1 (en) * | 2007-01-11 | 2008-12-04 | Tsuyoshi Imamura | Magnetic roller and manufacturing method thereof, developer carrier, development device, processing cartridge, and image forming apparatus |
WO2014112244A1 (en) * | 2013-01-15 | 2014-07-24 | ピーエム技研株式会社 | Magnetic roller |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7512367B2 (en) * | 2006-02-08 | 2009-03-31 | Xerox Corporation | Ultrasonic backer for bias transfer systems |
US20090116878A1 (en) * | 2007-11-05 | 2009-05-07 | Xerox Corporation | Color switching architecture |
US7919962B2 (en) * | 2007-11-20 | 2011-04-05 | Xerox Corporation | Magnet scanning device that scans a cylindrical magnet along a helical path |
ITUD20080147A1 (en) * | 2008-06-26 | 2009-12-27 | Danieli Davy Distington Ltd | COMPRESSION DEVICE FOR A SHREDDING SYSTEM |
CN102893222B (en) * | 2010-06-02 | 2015-03-25 | Pm技研株式会社 | Magnet roller |
CN103631115A (en) * | 2012-08-22 | 2014-03-12 | 大地磁性材料(香港)有限公司 | Manufacturing method for magnetic roller and system used therein |
EP2894519A1 (en) * | 2014-01-08 | 2015-07-15 | Earth Magnets (Hong Kong) Company Limited | Method for manufacturing magnetic rollers and system therefor |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2725109C2 (en) * | 1977-06-03 | 1985-12-05 | Magnetfabrik Bonn Gmbh Vorm. Gewerkschaft Windhorst, 5300 Bonn | Magnetic roller for electrographic developing and / or duplicating devices |
US4266328A (en) * | 1977-10-05 | 1981-05-12 | Hitachi Metals, Ltd. | Developing roll for use in electrostatic developing apparatus employing magnetic particles |
CA1198766A (en) * | 1981-04-20 | 1985-12-31 | Atsuo Tanaka | Magnetic rolls and a method of making the same |
US4608737A (en) * | 1984-08-20 | 1986-09-02 | Magnetic Technologies Corp. | Magnet developer rolls |
US6021296A (en) * | 1997-03-06 | 2000-02-01 | Bridgestone Corporation | Magnet roller and manufacturing method thereof |
US6012841A (en) * | 1998-01-22 | 2000-01-11 | Slaughter; Robert C. | Periapical film holder |
-
2000
- 2000-02-15 US US09/503,835 patent/US6422984B1/en not_active Expired - Lifetime
-
2002
- 2002-05-13 US US10/145,466 patent/US20020128137A1/en not_active Abandoned
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080298849A1 (en) * | 2007-01-11 | 2008-12-04 | Tsuyoshi Imamura | Magnetic roller and manufacturing method thereof, developer carrier, development device, processing cartridge, and image forming apparatus |
US8500615B2 (en) * | 2007-01-11 | 2013-08-06 | Ricoh Company, Ltd. | Magnetic roller and manufacturing method thereof, developer carrier, development device, processing cartridge, and image forming apparatus |
WO2014112244A1 (en) * | 2013-01-15 | 2014-07-24 | ピーエム技研株式会社 | Magnetic roller |
Also Published As
Publication number | Publication date |
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US6422984B1 (en) | 2002-07-23 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |
|
AS | Assignment |
Owner name: XEROX CORPORATION, CONNECTICUT Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:JPMORGAN CHASE BANK, N.A. AS SUCCESSOR-IN-INTEREST ADMINISTRATIVE AGENT AND COLLATERAL AGENT TO BANK ONE, N.A.;REEL/FRAME:061388/0388 Effective date: 20220822 |