Patents by Inventor Masashi Fujishima

Masashi Fujishima has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20150177651
    Abstract: A developing roller includes a roller main body disposed to face, without contact, an outer circumferential surface of an image carrier. The roller main body includes an aluminum oxide thin film and a resin coat layer, the aluminum oxide thin film being formed on an outer circumferential surface of a base body that is made of a metal including aluminum, the resin coat layer being formed on a surface of the aluminum oxide thin film that has been subjected to a predetermined heating process, the resin coat layer being made of a resin material and having electric conductivity.
    Type: Application
    Filed: December 17, 2014
    Publication date: June 25, 2015
    Inventors: Masashi Fujishima, Yuji Kamiyama, Tamotsu Shimizu, Shizuka Okada, Sakae Saito, Yasuhiro Oishi
  • Publication number: 20150177652
    Abstract: Developing device includes developing roller and magnetic roller. Developing roller includes aluminum oxide thin film and resin coat layer. Magnetic roller is disposed to face, without contact, outer circumferential surface of developing roller, and includes aluminum oxide thin film formed on outer circumferential surface of base body that is made of metal including aluminum. Magnetic roller forms toner layer on surface of developing roller via magnetic brush composed of toner and magnetic carrier. AC impedance Z1 is in range from 1.0×105? to 1.0×106? and surface roughness Ra of resin coat layer is in range from 0.057 ?m to 0.280 ?m, AC impedance Z1 being obtained when AC voltage at predetermined frequency is applied to between base body of magnetic roller and base body of developing roller in a state where the magnetic brush is formed on magnetic roller.
    Type: Application
    Filed: December 15, 2014
    Publication date: June 25, 2015
    Inventors: Tamotsu Shimizu, Shizuka Okada, Yuji Kamiyama, Sakae Saito, Yasuhiro Oishi, Masashi Fujishima, Chikara Ishihara
  • Patent number: 8824906
    Abstract: In the case of a standard sized sheet, a first controller sets a linear velocity D of an image bearing member at a first velocity and sets a linear velocity S of a toner bearing member so that S/D, which is a ratio of the linear velocity S to the linear velocity D, has a first value and a second controller sets the thickness of the toner layer carried on the toner bearing member at a first layer thickness. In the case of a long sheet, the first controller sets the linear velocity D at a second velocity slower than the first velocity and sets the linear velocity S so that the S/D has a second value larger than the first value and the second controller sets the thickness of the toner layer at a second layer thickness smaller than the first layer thickness.
    Type: Grant
    Filed: March 8, 2013
    Date of Patent: September 2, 2014
    Assignee: Kyocera Document Solutions Inc.
    Inventors: Chikara Ishihara, Masashi Fujishima
  • Patent number: 8774660
    Abstract: An image forming apparatus includes a separating unit for performing a stripping operation of forcibly returning toner particles carried on a toner bearing member to a developer bearing member, a sheet size discriminator for discriminating whether a sheet is a standard sized sheet or a long sheet, a determiner for determining whether or not there is any blank area of a predetermined length or longer in the sub scanning direction, where no toner image is to be substantially transferred, for each long sheet, and a controller for controlling the stripping operation. The controller causes the separating unit to perform the stripping operation at a developing timing of an electrostatic latent image corresponding to the blank area to be formed on the image bearing member when the sheet is a long sheet and when the blank area of the predetermined length or longer is present.
    Type: Grant
    Filed: July 12, 2012
    Date of Patent: July 8, 2014
    Assignee: Kyocera Document Solutions Inc.
    Inventor: Masashi Fujishima
  • Patent number: 8682228
    Abstract: A developer includes a developer carrying body that carries a two-component developer having a magnetic toner and a carrier. A toner carrying body opposes the developer carrying body and receives toner from the developer carrying body. An image carrying body develops an electrostatic latent image by toner carried on the toner carrying body. A first magnetic member is inside the developer carrying body and opposes a surface of the toner carrying body. A second magnetic member is inside the toner carrying body and opposes the surface of the developer carrying body. The second magnetic member is magnetized to an opposite polarity to the first magnetic member and generates a magnetic force at least on the surface of the toner carrying body in a range of 25 mT to 40 mT in a direction perpendicular to the surface of the toner carrying body.
    Type: Grant
    Filed: May 21, 2009
    Date of Patent: March 25, 2014
    Assignee: Kyocera Mita Corporation
    Inventors: Hisashi Mukataka, Masashi Fujishima, Yukihiro Mori
  • Publication number: 20130243454
    Abstract: In the case of a standard sized sheet, a first controller sets a linear velocity D of an image bearing member at a first velocity and sets a linear velocity S of a toner bearing member so that S/D, which is a ratio of the linear velocity S to the linear velocity D, has a first value and a second controller sets the thickness of the toner layer carried on the toner bearing member at a first layer thickness. In the case of a long sheet, the first controller sets the linear velocity D at a second velocity slower than the first velocity and sets the linear velocity S so that the S/D has a second value larger than the first value and the second controller sets the thickness of the toner layer at a second layer thickness smaller than the first layer thickness.
    Type: Application
    Filed: March 8, 2013
    Publication date: September 19, 2013
    Applicant: KYOCERA DOCUMENT SOLUTIONS INC.
    Inventors: Chikara Ishihara, Masashi Fujishima
  • Publication number: 20130022365
    Abstract: An image forming apparatus includes a separating unit for performing a stripping operation of forcibly returning toner particles carried on a toner bearing member to a developer bearing member, a sheet size discriminator for discriminating whether a sheet is a standard sized sheet or a long sheet, a determiner for determining whether or not there is any blank area of a predetermined length or longer in the sub scanning direction, where no toner image is to be substantially transferred, for each long sheet, and a controller for controlling the stripping operation. The controller causes the separating unit to perform the stripping operation at a developing timing of an electrostatic latent image corresponding to the blank area to be formed on the image bearing member when the sheet is a long sheet and when the blank area of the predetermined length or longer is present.
    Type: Application
    Filed: July 12, 2012
    Publication date: January 24, 2013
    Applicant: KYOCERA DOCUMENT SOLUTIONS INC.
    Inventor: Masashi Fujishima
  • Patent number: 8249489
    Abstract: A developing unit includes a developing roller which rotates about a rotational axis to supply toner to a photoreceptor, and a magnetic roller which forms a magnetic brush with a two-component developing agent having carrier and the toner and thereby forms a toner layer on the developing roller, the developing roller including: a cylindrical core portion which includes an electric conductor; a first resistive layer which covers a cylindrical surface of the core portion; a second resistive layer which covers the first resistive layer, and has electric-resistivity lower than that of the first resistive layer; and a current leakage control member which prevents leakage of electric current from the core portion toward the second resistive layer through an end of the developing roller along a direction of the rotational axis.
    Type: Grant
    Filed: July 15, 2011
    Date of Patent: August 21, 2012
    Assignee: Kyocera Document Solutions Inc.
    Inventors: Hiroyuki Hamakawa, Akihiro Watanabe, Masashi Fujishima, Hiroshi Yamazaki, Asami Kotera, Sayo Uemura
  • Patent number: 8112020
    Abstract: Embodiments relate to a developing device for use in an image-forming apparatus including a developing roller having a conductive base surface which may be covered with a resin layer containing an ion conductive material and a silicone-modified urethane resin having an ether structure. The resin layer may be a product of a crosslinking reaction of the silicone-modified urethane resin and the ion conductive material in the presence of a crosslinking agent and a crosslinking catalyst.
    Type: Grant
    Filed: March 17, 2009
    Date of Patent: February 7, 2012
    Assignee: KYOCERA MITA Corporation
    Inventors: Sayo Mabuchi, Hiroyuki Hamakawa, Akihiro Watanabe, Masashi Fujishima, Hiroshi Yamazaki, Asami Kotera
  • Publication number: 20110268479
    Abstract: A developing unit includes a developing roller which rotates about a rotational axis to supply toner to a photoreceptor, and a magnetic roller which forms a magnetic brush with a two-component developing agent having carrier and the toner and thereby forms a toner layer on the developing roller, the developing roller including: a cylindrical core portion which includes an electric conductor; a first resistive layer which covers a cylindrical surface of the core portion; a second resistive layer which covers the first resistive layer, and has electric-resistivity lower than that of the first resistive layer; and a current leakage control member which prevents leakage of electric current from the core portion toward the second resistive layer through an end of the developing roller along a direction of the rotational axis.
    Type: Application
    Filed: July 15, 2011
    Publication date: November 3, 2011
    Applicant: KYOCERA MITA CORPORATION
    Inventors: Hiroyuki HAMAKAWA, Akihiro WATANABE, Masashi FUJISHIMA, Hiroshi YAMAZAKI, Asami KOTERA, Sayo UEMURA
  • Patent number: 8014690
    Abstract: A developing unit has a voltage-applicator (80) to apply a developing bias voltage to a developing roller (72). The voltage-applicator (80) applies the developing bias voltage for a first duration to apply an AC voltage having a rectangular waveform, and a second duration to stop applying the AC voltage. The AC voltage has a duty ratio of 50% or more in a direction for causing toner to develop an electrostatic latent image. The number of cycles of the AC voltage in the first duration is two or more, and the AC voltage has a voltage in a direction for pulling the toner back to the developing roller, just before transition to the second duration. The developing unit suppresses occurrence of image unevenness due to a fluctuation in developing gap. Thus, an image forming apparatus equipped with the developing unit forms a high-quality image while suppressing image unevenness.
    Type: Grant
    Filed: March 5, 2008
    Date of Patent: September 6, 2011
    Assignee: Kyocera Mita Corporation
    Inventors: Shoichi Sakata, Takahisa Nakaue, Toyotsune Inoue, Akihiro Watanabe, Masashi Fujishima, Yukihiro Mori
  • Patent number: 8010025
    Abstract: A developing unit includes a developing roller which rotates about a rotational axis to supply toner to a photoreceptor, the developing roller including: a cylindrical core portion which includes an electric conductor; a first resistive layer which covers a cylindrical surface of the core portion; a second resistive layer which covers the first resistive layer, and has electric-resistivity lower than that of the first resistive layer; and a current leakage control member which prevents leakage of electric current from the core portion toward the second resistive layer through an end of the developing roller along a direction of the rotational axis.
    Type: Grant
    Filed: January 12, 2009
    Date of Patent: August 30, 2011
    Assignee: Kyocera Mita Corporation
    Inventors: Hiroyuki Hamakawa, Akihiro Watanabe, Masashi Fujishima, Hiroshi Yamazaki, Asami Kotera, Sayo Uemura
  • Patent number: 7937008
    Abstract: An image forming apparatus having a touchdown-development type developing apparatus, in which a toner collecting roller that collects scattered toner suspended in the vicinity of a toner holding body and a two-component developer holding body is arranged on the downstream side in a rotational direction of the two-component developer holding body from a closest position of the two-component developer holding body and the toner holding body, and between the two-component developer holding body and the housing wall, and further, bias means that applies a bias voltage for collecting the scattered toner to the toner collecting roller, and image density sensing means for sensing a density of a toner image developed on the electrostatic latent image holding body surface or a toner image on a transfer body onto which the toner image developed on the electrostatic latent image holding body surface is transferred to control the bias voltage are provided.
    Type: Grant
    Filed: February 12, 2008
    Date of Patent: May 3, 2011
    Assignee: Kyocera Mita Corporation
    Inventors: Masashi Fujishima, Akihiro Watanabe, Sayo Uemura, Yukihiro Mori
  • Patent number: 7848686
    Abstract: A developing device uses a two-component developer including at least carriers and toners. The toners are supplied to an image bearing member bearing an electrostatic latent image so that a toner image is developed from the electrostatic latent image. The developing device has a developing roller arranged to oppose the image bearing member; and a magnetic roller arranged to oppose the developing roller. The magnetic roller retains the two-component developer to supply toners to the developing roller. The developing roller and the magnetic roller are rotationally driven in directions to be opposite from one another at an opposed position, and a magnetic pole of the magnetic roller and a magnetic pole of the developing roller have magnetic polarities different from one another at the opposed position. A surface roughness of the magnetic roller is greater than a surface roughness of the developing roller.
    Type: Grant
    Filed: May 27, 2008
    Date of Patent: December 7, 2010
    Assignee: Kyocera Mita Corporation
    Inventors: Toyotsune Inoue, Takahisa Nakaue, Akihiro Watanabe, Masashi Fujishima, Shoichi Sakata, Yukihiro Mori
  • Patent number: 7826782
    Abstract: A developing device is provided for visualizing an electrostatic latent image previously formed on the surface of an image carrier as a toner image. The developing device has a developing roller placed at a position facing the image carrier, carrying a toner on the surface thereof, conveying the toner and flying the conveyed toner onto the surface of the image carrier; and a resin layer coated on the surface of the developing roller. The absolute value of the difference in charge between the toners in the upper and lower layers of the toner layer formed on the developing roller as the toner carried on the developing roller is 6 ?C/g or less.
    Type: Grant
    Filed: December 10, 2008
    Date of Patent: November 2, 2010
    Assignee: Kyocera Mita Corporation
    Inventors: Asami Kotera, Hiroyuki Hamakawa, Akihiro Watanabe, Masashi Fujishima, Hiroshi Yamazaki, Sayo Uemura
  • Patent number: 7826781
    Abstract: An image forming apparatus has a photoconductive member, and a developing roller develops a latent image on the photoconductive member by a first alternating-current bias in the form of a rectangular wave. The following relationships are satisfied in calculating the duty ratio (D1) of the first alternating-current bias using an application period of voltage in a direction to transfer the toner from the developing roller towards the photoconductive member as a positive period: a CV value in the number particle size distribution of the toner is ?25%, 4 ?m?Dt?7 ?m, 105 ?·cm?pv?109 ?·cm, 0.4 ?m?Ra?1.5 ?m, and 35%?D1?75%. where Dt denotes the volume average particle diameter of the toner, pv denotes the intrinsic resistance value of a developing roller surface, Ra denotes the arithmetic average roughness of the developing roller surface.
    Type: Grant
    Filed: March 19, 2008
    Date of Patent: November 2, 2010
    Assignee: Kyocera Mita Corporation
    Inventors: Masashi Fujishima, Shoichi Sakata, Takahisa Nakaue, Toyotsune Inoue, Akihiro Watanabe, Yukihiro Mori
  • Patent number: 7773921
    Abstract: An image forming apparatus includes a latent image carrying member, a two-component developer carrying member holding on an outer surface a developer containing carrier beads and toner particles, the two-component developer carrying member having a first magnetic element mounted therein, a toner carrying member carrying a thin toner layer on an outer surface, a toner collecting roller for collecting the toner particles scattered and suspended in the vicinity of the two-component developer carrying member and the toner carrying member, the toner collecting roller having a second magnetic element mounted therein, and a housing accommodating the two-component developer carrying member, the toner carrying member and the toner collecting roller. The toner collecting roller is located face to face with the two-component developer carrying member with the first and second magnetic elements disposed to face each other with oppositely directed polarities.
    Type: Grant
    Filed: January 25, 2008
    Date of Patent: August 10, 2010
    Assignee: Kyocera Mita Corporation
    Inventors: Masashi Fujishima, Kiyotaka Kobayashi, Yuki Matsui, Yukihiro Mori, Sayo Uemura, Akihiro Watanabe
  • Patent number: 7742727
    Abstract: An image forming apparatus has a photoconductive member on which a latent image is to be formed, a developing roller for developing the latent image on the photoconductive member by a first bias. A magnetic roller forms a magnetic brush thereon with a two-component developer and forms a thin toner layer on the developing roller by a second bias. The developing roller is aluminum with a surface treated for high resistance. The thickness (T) of the toner layer and the duty ratio (D1) of the first alternating-current bias satisfy relationships of the following equations for calculating the duty ratio (D1) using an application period of a voltage in a direction to transfer the toner from the developing roller towards the photoconductive member as a positive period: 7 ?m?T?13 ?m, and 35%?D1?70%.
    Type: Grant
    Filed: March 18, 2008
    Date of Patent: June 22, 2010
    Assignee: Kyocera Mita Corporation
    Inventors: Shoichi Sakata, Takahisa Nakaue, Toyotsune Inoue, Akihiro Watanabe, Masashi Fujishima, Yukihiro Mori
  • Publication number: 20090311012
    Abstract: This invention relates to a developing device 18 for use in an image-forming apparatus comprising a developing roller 100 having a conductive base surface 19 which may be covered with a resin layer 17 layer comprising an ion conductive material and a silicone-modified urethane resin having an ether structure.
    Type: Application
    Filed: March 17, 2009
    Publication date: December 17, 2009
    Applicant: KYOCERA MITA CORPORATION
    Inventors: Sayo Mabuchi, Hiroyuki Hamakawa, Akihiro Watanabe, Masashi Fujishima, Hiroshi Yamazaki, Asami Kotera
  • Publication number: 20090290912
    Abstract: A developer includes a developer carrying body that carries a two-component developer having a magnetic toner and a carrier. A toner carrying body opposes the developer carrying body and receives toner from the developer carrying body. An image carrying body develops an electrostatic latent image by toner carried on the toner carrying body. A first magnetic member is inside the developer carrying body and opposes a surface of the toner carrying body. A second magnetic member is inside the toner carrying body and opposes the surface of the developer carrying body. The second magnetic member is magnetized to an opposite polarity to the first magnetic member and generates a magnetic force at least on the surface of the toner carrying body in a range of 25 mT to 40 mT in a direction perpendicular to the surface of the toner carrying body.
    Type: Application
    Filed: May 21, 2009
    Publication date: November 26, 2009
    Applicant: Kyocera Mita Corporation
    Inventors: Hisashi Mukataka, Masashi Fujishima, Yukihiro Mori