Roller Patents (Class 399/357)
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Patent number: 6584296Abstract: An electro-mechanical roll such as a bias transfer roll for use in a printing or copying apparatus comprising a conductive core having a segmented layer of compressible material positioned in a tandem relation to another thereon to form a generally cylindrical roll member.Type: GrantFiled: November 30, 2001Date of Patent: June 24, 2003Assignee: Xerox CorporationInventor: Joseph A. Swift
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Publication number: 20030059236Abstract: A cleaning device of an image forming machine, comprising a pair of arm members each having one end portion pivotable about a support shaft, a cleaning roller rotatably supported between front end portions of the arm members via a shaft, helical compression springs for urging the arm members so as to bring the cleaning roller into contact under pressure with the surface of a photoconductor drum, a drive gear of the photoconductor drum, and a driven gear of the cleaning roller in mesh with the drive gear. Each of the arm members is disposed axially outwardly of the photoconductor drum. The center of the support shaft of each of the arm members is either placed on an extension of a line of action passing the point of engagement between the drive gear and the driven gear, or placed on an extension of a straight line passing the point of engagement, the straight line being within an angular range of some angle to the line of action.Type: ApplicationFiled: August 26, 2002Publication date: March 27, 2003Inventors: Masanobu Maeshima, Naoki Yamane
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Publication number: 20030049059Abstract: A method and structure for a cleaning a roller in an imaging apparatus includes the steps of providing a cleaner assembly with a skive blade in contact with the roller and forming a slot in a casing of the cleaner assembly. The skive blade can be selectively mounted on and removed from the cleaner assembly.Type: ApplicationFiled: February 21, 2002Publication date: March 13, 2003Applicant: NexPress Solutions LLCInventors: George D. Gross, Charles D. Odum
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Publication number: 20030039495Abstract: A cleaner includes a first roller and a second roller. The first roller is for removing foreign matter from a photosensitive body of an image forming device. The second roller is disposed in confrontation with the first roller. An electric field developed between the first roller and the second roller moves foreign matter having a predetermined charge polarity from the surface of the first roller to the surface of the second roller.Type: ApplicationFiled: August 21, 2002Publication date: February 27, 2003Applicant: BROTHER KOGYO KABUSHIKI KAISHAInventors: Takeshi Takami, Soichiro Nishimura
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Publication number: 20030039494Abstract: An image forming apparatus includes an image bearer, a charging device that charges a surface of the image bearer, a latent image forming device that forms a latent image on the image bearer, a developing device that develops the latent image on the image bearer with a spherical toner into a toner image, a transfer device that transfers the toner image to a transfer material, and a cleaning device that removes the spherical toner remaining on the image bearer after the toner image is transferred to the transfer material. The cleaning device including a cleaning member that removes the spherical toner on the image bearer while rotating and contacting the image bearer. An electric field is formed between the cleaning member and the image bearer by applying a voltage to the cleaning member so that the spherical toner adhered onto the image bearer is electrostatically attracted to the cleaning member.Type: ApplicationFiled: March 28, 2002Publication date: February 27, 2003Inventors: Masahiko Shakuto, Yasushi Nakazato, Osamu Naruse, Naomi Sugimoto, Takahiko Tokumasu, Kenji Sugiura, Tohru Nakano
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Publication number: 20020181983Abstract: A cleaning device of the present invention is configured to remove toner left on an image carrier after the transfer of a toner image from the image carrier to a recording medium. A rotatable cleaning roller contacts the image carrier for removing the toner left on the image carrier. A rotatable brush roller is positioned upstream of the cleaning roller in the direction of rotation of the image carrier and rubs against the surface of the image carrier and that of the cleaning roller. The cleaning device is free from defective cleaning despite the use of spherical, dry toner grains capable of forming high-quality toner images.Type: ApplicationFiled: May 14, 2002Publication date: December 5, 2002Inventors: Masahiko Shakuto, Yasushi Nakazato, Osamu Naruse, Naomi Sugimoto
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Publication number: 20020141771Abstract: While a first cleaning bias (600 V) is applied to a cleaning roller, a bias applied to a transfer roller is switched between a second transfer bias and a first transfer bias. The surface potential of a photosensitive drum changes depending on the bias applied to the transfer roller. When the photosensitive drum contacts the transfer roller while the second transfer bias is applied to the transfer roller, the surface potential of the photosensitive drum becomes the second surface potential (approximately 900-1000 V). When the photosensitive drum having the second surface potential contacts the cleaning roller, the cleaning roller collects toner remaining on the photosensitive drum. When the photosensitive drum contacts the transfer roller while the first transfer bias is applied to the transfer roller, the surface potential of the photosensitive drum becomes the first surface potential (approximately 200-400 V).Type: ApplicationFiled: March 25, 2002Publication date: October 3, 2002Applicant: BROTHER KOGYO KABUSHIKI KAISHAInventor: Soichiro Nishimura
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Patent number: 6448990Abstract: Toner processing systems and electronic display devices and methods are described. In one embodiment, a toner processing system comprises an enclosure and an electrostatic toner recovery assembly supported within the enclosure for electrostatically recovering unfused toner from a print media surface. A toner development assembly is supported within the enclosure proximate the electrostatic toner recovery assembly and is configured to receive recovered toner from the electrostatic toner recovery assembly for reuse on the print media surface.Type: GrantFiled: November 7, 2000Date of Patent: September 10, 2002Assignee: Hewlett-Packard CompanyInventors: Thomas Camis, Samuel A. Johnson
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Publication number: 20020118988Abstract: A device for engaging and disengaging an object in one direction and a photosensitive medium cleaning device of a liquid printer using the same are provided. The device for engaging and disengaging includes a housing, a driving motor disposed at the housing, a rotating bracket, rotatably disposed at the housing, for supporting the object, and a cam unit, capable of rotating and moving linearly by a rotating force of the driving motor, for transferring the rotating bracket to one side by being rotated after being moved linearly to the rotating bracket while the driving unit is rotating in one direction, the cam unit being separated from the rotating bracket enabling the rotating bracket to return to an initial position while the driving motor is rotating reversely.Type: ApplicationFiled: December 28, 2001Publication date: August 29, 2002Applicant: SAMSUNG ELECTRONICS CO., LTD.Inventors: Kwang-taek Lim, Jin-soo Lee
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Patent number: 6421511Abstract: A transfer device for transferring a toner image formed on an image carrier onto a transfer material conveyed on a transfer belt. The transfer device includes a cleaning member having a dielectric surface layer for cleaning a surface of the transfer belt, and a bias application unit for applying to the cleaning member a cleaning bias having an opposite polarity to an electric charge polarity of a toner forming the toner image. Further, specific characteristic values of the dielectric surface layer are set to achieve a higher than predetermined cleaning level, such as setting a volume resistivity of the dielectric surface layer is set to 1E4 ohms/square or more.Type: GrantFiled: December 1, 2000Date of Patent: July 16, 2002Assignee: Ricoh Company, Ltd.Inventors: Toshihiro Sugiyama, Hiroshi Ishii, Hiroshi Saitoh, Atsuko Miyashita
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Patent number: 6389253Abstract: An image forming apparatus includes an image bearing member for bearing an electrostatic latent image, and a developing device for developing the electrostatic latent image with a developer and collecting the developer remaining on the image bearing member including a developer carrying member for carrying the developer. The developer carried by the developer carrying member comes into contact with the image bearing member as the developer carrying member moves and a regulating member for regulating a layer thickness of the developer carried by the developer carrying member. The regulating member regulates the layer thickness of the developer carried by the developer carrying member so that there will be three to eight layers, wherein V2/V1>1.54 holds where V1 is a peripheral velocity of said image bearing member and V2 is a peripheral velocity of said developer carrying member.Type: GrantFiled: August 1, 2000Date of Patent: May 14, 2002Assignee: Canon Kabushiki KaishaInventors: Makoto Nonomura, Yukihiro Ozeki, Katsuhiro Sakaizawa, Manami Sekiguchi
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Patent number: 6378161Abstract: A cleaning element (1) for use in the fuser section of electrostatographic reproduction or printing apparatus. The element includes projections projecting from an outer surface to form a pile (5). The cross section of each projection has a cross section having a peripheral dimension and an area. The ratio of the peripheral dimension and area is greater than the same ratio for a projection of circular or substantially circular and equal area of cross section. The projections may be formed by tri-lobal fibres.Type: GrantFiled: August 13, 1999Date of Patent: April 30, 2002Assignee: BMP Europe LimitedInventor: Steve Parry
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Patent number: 6345166Abstract: A developer scraping member for scraping developer from a developer carrying member has a surface layer having a foamed member, a base layer provided inside of the surface layer, and an intrusion preventing layer provided between the surface layer and the base layer. The intrusion preventing layer prevents the developer, which has intruded into the surface layer, from intruding into the base layer.Type: GrantFiled: June 22, 2000Date of Patent: February 5, 2002Assignee: Canon Kabushiki KaishaInventors: Katsuhiro Sakaizawa, Yukihiro Ohzeki, Makoto Nonomura, Manami Sekiguchi
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Publication number: 20020009316Abstract: The present invention concerns a cleaning apparatus to clean an image bearing member used in electrophotographic process and an image forming system equipped with the cleaning system.Type: ApplicationFiled: May 1, 2001Publication date: January 24, 2002Inventors: Isao Endo, Hiroshi Morimoto
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Patent number: 6335066Abstract: A disposal cartridge for use in an image forming apparatus includes a sheet and a roller. An area of the sheet is at least equal to an area of the entire circumferential surface of the roller. The sheet is detachably bonded to an entire circumferential surface of the roller. The roller attracts toner and is detachably and rotatably mounted on the disposal cartridge.Type: GrantFiled: December 29, 1998Date of Patent: January 1, 2002Assignee: Ricoh Company, Ltd.Inventor: Shigemi Kanda
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Patent number: 6334042Abstract: A method and apparatus for increasing the useful life of cleaning members within an image forming apparatus by side shifting a cleaning member laterally in relation to a photoreceptor. In various exemplary embodiments, the cleaning apparatus includes a cleaning member mounted on a shaft, and side shifting member that moves the shaft along its axis to move the cleaning member laterally. In various exemplary embodiments, the cleaning apparatus moves the cleaning member laterally in a continuous sweeping motion. In various exemplary embodiments, the cleaning apparatus moves the cleaning member laterally in incremental steps.Type: GrantFiled: November 28, 2000Date of Patent: December 25, 2001Assignee: Xerox CorporationInventor: Lisbeth S. Quesnel
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Patent number: 6320642Abstract: A cooling section 400 for cooling a recording material A, which is a recording material, is disposed in a downstream portion of a heat development section 18. The cooling section 400 has a pair structure consisting of a metal roller 404 and a roller 402 made of an elastic material. The metal roller 404 having excellent heat conductivity is brought into contact with an image forming surface of the recording material A. As a result of the foregoing structure, the recording material A subjected to the heat development can uniformly be cooled to a temperature not higher than a development interruption temperature during conveyance in the cooling section 400. The metal roller may be modified variously. For example, the metal roller is cooled by a cooling mechanism or replaced by a belt.Type: GrantFiled: August 10, 1999Date of Patent: November 20, 2001Assignee: Fuji Photo Film Co., Ltd.Inventors: Masaharu Ogawa, Nobuyuki Torisawa
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Patent number: 6272301Abstract: An image forming apparatus includes an image bearing member for bearing an electrostatic image; a developing device for developing the electrostatic image on the image bearing member with toner into a toner image; a transfer device for transferring the toner image onto a transfer material; a charging and cleaning device for removing residual toner after image transfer from the image bearing member and for charging the image bearing member; wherein the charging and cleaning device includes a rotatable member which has an electroconductive foam for retaining electroconductive particles and which is rotatable while rubbing the image bearing member.Type: GrantFiled: September 22, 1999Date of Patent: August 7, 2001Assignee: Canon Kabushiki KaishaInventors: Masaya Kawada, Toshiyuki Ehara, Harumi Ishiyama
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Patent number: 6272302Abstract: The present invention relates to an image forming apparatus in which a developing device has a developer bearing member for bearing and carrying a developer thereon, which is provided in opposed relationship with an image bearing member; and developer collecting means provided in opposed relationship with the developer bearing member and the image bearing member, and the developer collecting means collects any unused developer on the developer bearing member and any untransferred developer on the image bearing member.Type: GrantFiled: March 7, 2000Date of Patent: August 7, 2001Assignee: Canon Kabushiki KaishaInventor: Takeshi Yamamoto
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Patent number: 6219505Abstract: In a first paper-dust removing device, a brush is supported by a support member that is attached to the interior of a casing. The first paper-dust removing device mainly removes pulp fibers of the paper dust, and is located downstream from a transfer position in the photosensitive drum rotating direction. A second paper-dust removing device is additionally provided. The second paper-dust removing device includes a support member that is attached to a casing of a developing cartridge. The support member supports a non-woven fabric that is lined by a sponge. The second paper-dust removing device mainly removes talc in the paper dust. The second paper-dust removing device is located downstream from the first removing device in the photosensitive drum rotating direction. In the second device, the non-woven fabric is contacted with the photosensitive drum at substantially zero contact pressure.Type: GrantFiled: September 30, 1999Date of Patent: April 17, 2001Assignee: Brother Kogyo Kabushiki KaishaInventors: Shougo Sato, Masahiro Ishii, Satoru Ishikawa, Takeshi Fuwazaki
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Patent number: 6215975Abstract: A cleaning station for a fusing member has first and second cleaner rollers. The first cleaner roller is coated with a sticky or adhesive first toner layer. The first toner layer contacts the fuser member for cleaning. The second cleaner roller is coated with a sticky or adhesive second toner layer. The second toner layer is in contact with the first toner layer. The second cleaner roller defines apertures connecting to an internal reservoir. Excess toner from the second toner layer collects in the internal reservoir.Type: GrantFiled: July 26, 1999Date of Patent: April 10, 2001Assignee: Xerox CorporationInventors: John S. Berkes, Gerald M. Fletcher
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Patent number: 6192214Abstract: A roller cleaning apparatus of a liquid electrophotographic printer cleans a circumferential surface of a roller where a film is formed due to contact with a photoreceptor medium. The apparatus includes an abrasion member installed to be in contact with the roller for abrading the film using friction. Thus, contamination of the roller can be prevented.Type: GrantFiled: October 1, 1999Date of Patent: February 20, 2001Assignee: Samsung Electronics Co. Ltd.Inventors: Kyung-hwan Kim, Chang-soo Rhee
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Patent number: 6185391Abstract: An image forming apparatus having a mechanism for removing a deteriorated layer of the transfer roller is disclosed, by which the critical surface tension of the transfer roller can be suitably maintained. The apparatus includes primary transfer roller, a fixing roller, a backup roller, a belt-like photosensitive body, an isolating plate, a first cleaning roller, a polishing roller, a second cleaning roller, a brush roller, and a cleaner case. The toner image on the belt-like photosensitive body is transferred to the primary transfer roller according to the rotation of the backup roller. The toner image is then pressed and fixed by the fixing roller, and the image is further transferred to a paper which is moved and output. A deteriorated layer of the transfer roller is scraped away by the polishing roller, and remaining polishing dust is removed by the second cleaning roller. Additionally, polishing dust remaining on the polishing roller is removed by the brush roller.Type: GrantFiled: January 20, 2000Date of Patent: February 6, 2001Assignee: NEC CorporationInventor: Yoshiyasu Tanioka
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Patent number: 6118970Abstract: A cleaning roller is used for electrostatically attracting residual toner left on a photoconductive drum. The cleaning roller includes a shaft and a member formed on the shaft to cover the shaft. The member has contact portions that lie in a cylindrical plane and a plurality of recesses that are formed in the member and bounded by the contact portions. The contact portions are in contact with the photoconductive drum to attract residual toner left on the photoconductive drum. The recesses hold therein the residual toner attracted to the contact portions. The recesses have openings that lie in the cylindrical plane such that a ratio of the areas of the contact portions to the areas of the openings is in the range from 3:7 to 1:1. The openings of the recesses have effective diameters in the range from 50 to 150 .mu.m if the toner particles have effective diameters in the range from 6 to 9 .mu.m. The cleaning roller includes a metal shaft and a resilient member formed on the metal shaft to cover the metal shaft.Type: GrantFiled: June 3, 1999Date of Patent: September 12, 2000Assignee: Oki Data CorporationInventors: Masayuki Suzuki, Hirokazu Ando, Takao Mizutani, Masao Isoda
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Patent number: 6081680Abstract: An image support apparatus including a pair of rotatable disk shaped members, a cylindrical member supported and fixed at both ends by the pair of disk shaped members, a flexible image supporter shaped like a thin cylinder and formed with a photosensitive layer at the outer peripheral surface, support members being disposed on an outer peripheral surface of the cylindrical member for supporting the image supporter, a charge roller abutting the outer peripheral surface of the image supporter for uniformly charging the outer peripheral surface, and a frame. A distance between a portion of the image supporter supported by the support member and an end of the charge roller is set to a length to prevent the image supporter, which is bent as the charge roller abuts the image supporter, from becoming permanently deformed.Type: GrantFiled: February 2, 1998Date of Patent: June 27, 2000Assignee: Seiko Epson CorporationInventors: Yujiro Nomura, Saburo Furukawa, Kaneo Yoda, Kuniaki Tanaka
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Patent number: 6026271Abstract: An image forming apparatus is capable of effectively removing a residual toner on a surface of an intermediate transfer roller by a cleaning roller and a predetermined plate form blade without injuring the surface of the intermediate transfer roller. In the electrophotographic type image forming apparatus, the cleaning roller rotates in an opposite direction to the rotating direction of the intermediate transfer roller and is provided in contact with the surface of the intermediate transfer roller. Also, a plate form blade contacting with the cleaning roller is provided. Also, at least the cleaning roller is movable toward and away from the intermediate roller.Type: GrantFiled: April 12, 1999Date of Patent: February 15, 2000Assignee: NEC CorporationInventor: Masato Saitoh
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Patent number: 5970302Abstract: A method of cleaning is used to remove residual toner in an electrophotographic printer. After a printing operation, some amount of normally-charged toner and reversely-charged toner is left on the photoconductive drum and rollers such as charging rollers, transfer roller, and cleaning roller in contact with the photoconductive drum. A potential difference is applied between two members, for example, the cleaning roller and the photoconductive drum in electrical contact with each other so as to cause the residual toner to migrate from one member to the other. The potential differences are applied at specific timings so that the residual toner migrates properly onto the rotating photoconductive drum and is carried to the developing section for reuse.Type: GrantFiled: September 30, 1998Date of Patent: October 19, 1999Assignee: Oki Data CorporationInventor: Tsutomu Yamane
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Patent number: 5864741Abstract: An apparatus for efficient cleaning of the imaging surface. The primary cleaner is a rotating collection roll located directly opposite from and on the other side of the imaging surface from the ultrasonic cleaning assist device. The ultrasonic energy is used to remove the toner from the imaging surface enabling attraction toward the biased collection roll. The ultrasonic energy decreases the amount of residual toner remaining after transfer. The residual toner that is not cleaned from the surface by the collection roll is removed from the surface by the rotating biased conductive brush, which is the secondary cleaner. The collection roll is contactless in that it does not come into contact with the photoreceptor. In another embodiment of the invention, the primary cleaner and the secondary cleaner are collection rolls with ultrasonic cleaning assist devices directly under each collection roll. The entire cleaning system is contactless.Type: GrantFiled: April 17, 1997Date of Patent: January 26, 1999Assignee: Xerox CorporationInventors: David B. Montfort, Nero R. Lindblad
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Patent number: 5835837Abstract: An image forming substance removing apparatus for removing an image forming substance from an image holding member has a separating device for separating the image forming substance from the image holding member by separating a separating member having adhesive force stronger than adhesive force between the image holding member and the image forming substance attached onto this image holding member from the image forming substance on the image holding member after this separating member comes in contact with the image forming substance on the image holding member; and a cleaner for cleaning the separating member by removing the image forming substance attached onto the separating member therefrom.Type: GrantFiled: October 3, 1997Date of Patent: November 10, 1998Assignee: Ricoh Company, Ltd.Inventors: Masatoshi Saitoh, Yasuhiro Takahashi, Hisao Watanabe, Masaru Shinkai, Hiroshi Kondoh
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Patent number: 5797078Abstract: An apparatus for cleaning a charge retentive surface of a photoreceptor which includes a rotating brush for cleaning the charge retentive surface of a photoreceptor. A spring or other device is used to maintain constant, uniformly distributed contact between the charge retentive surface and the rotating cleaning member together. The use of one or more pressure rollers to maintain the cleaning brush next to the photoreceptor belt can prevent undesirable friction, heat and/or static charge buildup adjacent to the photoreceptor, and can prevent photoreceptor jamming and other malfunctions. The resulting self regulating cleaning brush contact improves photoreceptor cleaning effectiveness despite brush aging, bristle wear or set, or other factors effecting the radius of the cleaning brush or its relative positioning in the photoreceptor cleaning assembly. The present invention results in the uniform distribution of the contact pressure on the photoreceptor, which may monitored and/or be controlled.Type: GrantFiled: July 9, 1993Date of Patent: August 18, 1998Assignee: Xerox CorporationInventors: Douglas W. Sass, Stephen T. Dunn, Ronald E. Godlove
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Patent number: 5781832Abstract: An image forming apparatus has an image bearing member, charging means for uniformly charging the image bearing member, electrostatic image forming means for forming an electrostatic image on the image bearing member charged by the charging means, developing means for developing the electrostatic image on the image bearing member with a toner and also recovering any residual toner on the image bearing member, and transferring means for transferring the toner image to a transfer member conveyed. Upon re-operation after jam, at least one full rotation of the image bearing member effects the recovery of the toner on the image bearing member by the developing means with the charging by the charging means being rendered OFF.Type: GrantFiled: May 2, 1997Date of Patent: July 14, 1998Assignee: Canon Kabushiki KaishaInventors: Ryo Inoue, Kenichiro Waki, Hiroyuki Suzuki
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Patent number: 5752146Abstract: A laser printer performing a developing operation on a positively chargeable photosensitive drum with using positively chargeable toners. The printer includes photosensitive drum, a laser scanner unit for forming an electrostatic latent image on the photosensitive drum, a developing roller for developing the electrostatic latent image by a toner layer consisting of toners having positively chargeable characteristic, a thickness regulation blade for regulating the thickness of the toner layer on the developing roller such that the amount of toners in the toner layer is not more than 0.5 mg/cm.sup.2, a scorotoron charger confronting the photosensitive drum in out of contact therefrom for charging the rotating photosensitive drum to the positive polarity, and a transfer roller for transferring the toner image onto a printing sheet. By the thickness regulation of the toner layer, each toner is surely imparted with positive polarity.Type: GrantFiled: December 5, 1996Date of Patent: May 12, 1998Assignee: Brother Kogyo Kabushiki KaishaInventor: Shougo Sato
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Patent number: 5685043Abstract: A system in which a contact cleaning cylinder is brought into moving synchronous contact with the surface of a cylindrical member to be cleaned to clean the surface.Type: GrantFiled: July 24, 1995Date of Patent: November 11, 1997Assignee: Xerox CorporationInventors: Gina M. LaManna, Gary W. Smallman, David J. Kilmer, Richard C. Petralia, Patrick R. Shane
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Patent number: 5617194Abstract: There is provided a cleaning unit for removing residual toner present on the periphery of a photoconductive drum after toner image transfer, which includes: a main blade for scraping the toner from the surface of the photoconductive drum; and a cleaning roller disposed below the main blade and abutting against the periphery of the photoconductive drum. The inner space of the cleaning housing is divided into a cleaning chamber and a toner storage by a separator plate. A spacing between the lower end of the separator plate and the periphery of the cleaning roller is adjusted to preferably 1 mm to 2 mm, more preferably 1.3 mm to 1.5 mm. By thus adjusting the spacing, the toner is compressed when passing through the spacing and, hence, the toner transportation pressure is increased.Type: GrantFiled: March 6, 1995Date of Patent: April 1, 1997Assignee: Mita Industrial, Co., Ltd.Inventors: Hiroki Morishita, Susumu Taniguchi, Shinichi Kotera
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Patent number: 5572293Abstract: A system for cleaning a charge inducing member comprising a cleaning element for establishing relative lineal as well as rotary movement between the cleaning element and charge inducing member. Embodiments include various mechanisms for imparting axial reciprocal motion to the cleaning element and for disabling reciprocation of the cleaning element or separating the cleaning element and charging member from each other during sensitive portions of a photoduplication cycle.Type: GrantFiled: October 13, 1994Date of Patent: November 5, 1996Assignee: Ricoh Company, Ltd.Inventors: Nobuo Kikuchi, Kouichi Yamazaki, Sadao Takahashi, Kentaro Matsumoto, Tadashi Hayakawa, Yoshiaki Miyashita, Takeshi Tabuchi, Hirohisa Ohtsuka, Takaaki Tawada