Patents by Inventor Hiroshi Isokawa

Hiroshi Isokawa 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: 20100157461
    Abstract: According to one embodiment, a signal reproducing circuit reproduces a signal read from a recording medium on which the signal has been recorded by perpendicular magnetic recording. The signal reproducing circuit includes a waveform equalizer that equalizes the waveform of the signal based on a waveform equalization target, where D is a one-bit delay operator, previously stored in a storage module. The waveform equalization target is any one of a[1+3D+2D2] [1?D], a[2+5D+2D2] [1?D], and a[1+4D+2D2] [1?D] where a is an integer.
    Type: Application
    Filed: December 18, 2009
    Publication date: June 24, 2010
    Applicant: TOSHIBA STORAGE DEVICE CORPORATION
    Inventors: Hiroaki UENO, Hiroshi ISOKAWA
  • Publication number: 20090297239
    Abstract: Disclosed a cleaning apparatus including: a brush to remove an adhered matter adhered to a photoconductor drum; wherein the brush includes: a first brush portion which contacts an end portion of the photoconductor drum in an axial direction, which portions is on a circumferential surface of the photoconductor drum, and in which portion a conductive base substance is exposed; and a second brush portion which contacts only a photosensitive layer on the circumferential surface of the photoconductor drum, and an electric resistance value of the first brush portion is larger than that of the second brush when a bias current is applied.
    Type: Application
    Filed: May 22, 2009
    Publication date: December 3, 2009
    Applicant: Konica Minolta Business Technologies, Inc.
    Inventors: Azusa Aso, Nobuhiko Okano, Kiyoaki Kawamoto, Tetsuya Ishikawa, Hiroshi Isokawa
  • Publication number: 20090285599
    Abstract: An image forming apparatus including: an image carrier; a toner image forming section; a transfer section for transferring the toner image onto transfer sheet; a separation section for separating the transfer sheet from the image carrier; and a process cartridge for holding as a unit and detachably from the main unit the image carrier, the toner image forming section, the transfer section, and the separation section wherein the separation section comprises a resin guide member, which is the base for the separation section, a separation pawl for separating transfer sheet from the image carrier, a metal reference plate fixed to the resin guide member and a resin engaging member fixed to the reference plate, the engaging member engaging with the support provided in the process cartridge so that the support supports the separation section in a way that the separation section can move in the axial direction of the image carrier.
    Type: Application
    Filed: May 12, 2009
    Publication date: November 19, 2009
    Applicant: Konica Minolta Business Technologies, Inc.
    Inventor: Hiroshi ISOKAWA
  • Patent number: 7280796
    Abstract: An image forming apparatus including: a cleaning member for cleaning an image carrier after a toner image on the image carrier has been transferred; a toner recycling device for conveying toner removed by the cleaning member to a developing device; a collection section where the toner removed by the cleaning member is collected; a branch conveyance path, branched from the toner recycling device, for conveying the toner to the collection section; and an air pump, provided on the branch conveyance path, for sucking air with the toner; wherein, whether the toner is conveyed from the cleaning member to the collection section or to the developing device is switched corresponding to whether the air pump operates or does not operate.
    Type: Grant
    Filed: July 12, 2005
    Date of Patent: October 9, 2007
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Hiroshi Isokawa, Ritsuo Fujii, Seiji Yamaguchi
  • Patent number: 7155149
    Abstract: An image apparatus comprising a toner supplying device; a toner receiving device; a first toner conduit communicating with the toner receiving device to feed a toner supplied from the toner supplying device; a first feeding device which forms an air stream to feed the toner through the first toner conduit; and a detector which monitors abnormality condition in the course of toner supplying in the apparatus.
    Type: Grant
    Filed: May 17, 2004
    Date of Patent: December 26, 2006
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Ritsuo Fujii, Seiji Yamaguchi, Hiroshi Isokawa, Yasuo Shiokawa
  • Patent number: 7092663
    Abstract: An image forming apparatus, including: an image carrier; a transfer device for transferring toner images carried on the image carrier onto the recording material; and a pressing section for pressing the transfer material onto the image carrier; wherein the pressing section is trapezoidal, including: a straight edge portion positioned at the center of the pressing section, perpendicular to the feeding direction of the recording material, and sloped edge portions, wherein the width of the straight edge portion is equal to or greater than 95% of the width of the recording material.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: August 15, 2006
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Kouki Takahashi, Ritsuo Fujii, Hirotaka Kabashima, Hiroshi Isokawa
  • Patent number: 7082279
    Abstract: A toner replenishment device has: a toner reservoir section for supplying a toner to a development device; a supply fluid conveyance section for conveying a fluid mixture of toner and air from the toner reservoir section through a supply conveying path; a toner separation section for separating the fluid mixture which has been conveyed by the supply fluid conveyance section into the toner and the air and supplying the toner to the development device; a circulation fluid conveyance section for circulating at least air separated from the fluid mixture, from the toner separation section to the toner reservoir section through a circulation conveyance path; and a capacity variable member connected with the supply conveying path or the circulation conveyance path, capable of absorbing a pressure fluctuation of the fluid mixture or the air by varying a capacity of the member.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: July 25, 2006
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Ritsuo Fujii, Seiji Yamaguchi, Hiroshi Isokawa
  • Patent number: 7062206
    Abstract: A toner supplying apparatus for feeding a toner to a developing device to develop a latent image on an image bearing member. The apparatus includes: a toner separating member communicating to the developing device, to separate the toner from the mixed fluid containing the toner and an air stream; a separating side flow control mechanism disposed between the toner separating member and the developing device; a wall to cover at least a portion of the flow control mechanism, having a clearance therebetween; and an after-separation storage to store the toner separated from the mixed fluid.
    Type: Grant
    Filed: March 19, 2004
    Date of Patent: June 13, 2006
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Ritsuo Fujii, Seiji Yamaguchi, Hiroshi Isokawa, Yasuo Shiokawa
  • Publication number: 20060088352
    Abstract: An image forming apparatus including: a cleaning member for cleaning an image carrier after a toner image on the image carrier has been transferred; a toner recycling device for conveying toner removed by the cleaning member to a developing device; a collection section where the toner removed by the cleaning member is collected; a branch conveyance path, branched from the toner recycling device, for conveying the toner to the collection section; and an air pump, provided on the branch conveyance path, for sucking air with the toner; wherein, whether the toner is conveyed from the cleaning member to the collection section or to the developing device is switched corresponding to whether the air pump operates or does not operate.
    Type: Application
    Filed: July 12, 2005
    Publication date: April 27, 2006
    Inventors: Hiroshi Isokawa, Ritsuo Fujii, Seiji Yamaguchi
  • Patent number: 7010251
    Abstract: A toner conveyance device for conveying toner particles including: a toner mixing unit having a toner introducing portion to introduce toner particles, for mixing the toner particles from the toner introducing portion with air to make a toner fluid; a first conveyor for receiving the toner fluid in the toner mixing unit and conveying; a toner separation unit for separating the toner fluid conveyed by the first conveyor into air and toner particles, the toner separation unit having a toner discharging portion for discharging the separated toner particles to an outside; a second conveyor for conveying the air separated by the toner separation unit back to the toner mixing unit; and a tightly closed circulation path of air, formed starting at the toner mixing unit which leads to the toner separation unit through the first conveyor and returning back to the toner mixing unit through the second conveyor.
    Type: Grant
    Filed: November 24, 2003
    Date of Patent: March 7, 2006
    Assignee: Konica Minolta Holdings, Inc.
    Inventors: Kazumichi Yamauchi, Ritsuo Fujii, Satoshi Sakata, Seiji Yamaguchi, Hiroshi Isokawa, Hiroyuki Watanabe, Yasuo Shiokawa
  • Publication number: 20050260016
    Abstract: An image forming apparatus, including: an image carrier; a transfer device for transferring toner images carried on the image carrier onto the recording material; and a pressing section for pressing the transfer material onto the image carrier; wherein the pressing section is trapezoidal, including: a straight edge portion positioned at the center of the pressing section, perpendicular to the feeding direction of the recording material, and sloped edge portions, wherein the width of the straight edge portion is equal to or greater than 95% of the width of the recording material.
    Type: Application
    Filed: November 24, 2004
    Publication date: November 24, 2005
    Inventors: Kouki Takahashi, Ritsuo Fujii, Hirotaka Kabashima, Hiroshi Isokawa
  • Publication number: 20050201780
    Abstract: A toner replenishment device has: a toner reservoir section for supplying a toner to a development device; a supply fluid conveyance section for conveying a fluid mixture of toner and air from the toner reservoir section through a supply conveying path; a toner separation section for separating the fluid mixture which has been conveyed by the supply fluid conveyance section into the toner and the air and supplying the toner to the development device; a circulation fluid conveyance section for circulating at least air separated from the fluid mixture, from the toner separation section to the toner reservoir section through a circulation conveyance path; and a capacity variable member connected with the supply conveying path or the circulation conveyance path, capable of absorbing a pressure fluctuation of the fluid mixture or the air by varying a capacity of the member.
    Type: Application
    Filed: September 24, 2004
    Publication date: September 15, 2005
    Inventors: Ritsuo Fujii, Seiji Yamaguchi, Hiroshi Isokawa
  • Publication number: 20050041998
    Abstract: An image apparatus comprising a toner supplying device; a toner receiving device; a first toner conduit communicating with the toner receiving device to feed a toner supplied from the toner supplying device; a first feeding device which forms an air stream to feed the toner through the first toner conduit; and a detector which monitors abnormality condition in the course of toner supplying in the apparatus.
    Type: Application
    Filed: May 17, 2004
    Publication date: February 24, 2005
    Applicant: Konica Minolta Business Technologies, Inc.
    Inventors: Ritsuo Fujii, Seiji Yamaguchi, Hiroshi Isokawa, Yasuo Shiokawa
  • Publication number: 20040247344
    Abstract: A toner supplying apparatus for feeding a toner to a developing device to develop a latent image on an image bearing member. The apparatus includes: a toner separating member communicating to the developing device, to separate the toner from the mixed fluid containing the toner and an air stream; a separating side flow control mechanism disposed between the toner separating member and the developing device; a wall to cover at least a portion of the flow control mechanism, having a clearance therebetween; and an after-separation storage to store the toner separated from the mixed fluid.
    Type: Application
    Filed: March 19, 2004
    Publication date: December 9, 2004
    Applicant: KONICA MINOLTA BUSINESS TECHNOLOGIES, INC.
    Inventors: Ritsuo Fujii, Seiji Yamaguchi, Hiroshi Isokawa, Yasuo Shiokawa
  • Patent number: 6829463
    Abstract: This invention relates to a toner replenishing method including the steps of conveying, from a toner storing section which forms a fluid mixture of toner and air, the fluid mixture to a toner separating section provided away from the toner storing section through toner supplying fluid conveying system, separating the toner from air in the toner separating section, and supplying the toner from the toner separating section to a developing unit, and a toner replenishing unit which practices the toner replenishing method. The toner replenishing method of the invention further includes the step of returning part of air separated from the toner from the toner separating section to the toner storing section by using a returning fluid conveying system. The toner replenishing unit of the present invention includes a returning fluid conveying system between the toner storing section and the toner separating section.
    Type: Grant
    Filed: January 21, 2003
    Date of Patent: December 7, 2004
    Assignee: Konica Corporation
    Inventors: Ritsuo Fujii, Seiji Yamaguchi, Hiroshi Isokawa
  • Publication number: 20040105704
    Abstract: A toner conveyance device for conveying toner particles including: a toner mixing unit having a toner introducing portion to introduce toner particles, for mixing the toner particles from the toner introducing portion with air to make a toner fluid; a first conveyor for receiving the toner fluid in the toner mixing unit and conveying; a toner separation unit for separating the toner fluid conveyed by the first conveyor into air and toner particles, the toner separation unit having a toner discharging portion for discharging the separated toner particles to an outside; a second conveyor for conveying the air separated by the toner separation unit back to the toner mixing unit; and a tightly closed circulation path of air, formed starting at the toner mixing unit which leads to the toner separation unit through the first conveyor and returning back to the toner mixing unit through the second conveyor.
    Type: Application
    Filed: November 24, 2003
    Publication date: June 3, 2004
    Applicant: KONICA MINOLTA HOLDINGS, INC.
    Inventors: Kazumichi Yamauchi, Ritsuo Fujii, Satoshi Sakata, Seiji Yamaguchi, Hiroshi Isokawa, Hiroyuki Watanabe, Yasuo Shiokawa
  • Publication number: 20030142999
    Abstract: This invention relates to a toner replenishing method including the steps of conveying, from a toner storing section which forms a fluid mixture of toner and air, the fluid mixture to a toner separating section provided away from the toner storing section through toner supplying fluid conveying means, separating the toner from air in the toner separating section, and supplying the toner from the toner separating section to a developing unit, and a toner replenishing unit which practices the toner replenishing method. The toner replenishing method of the invention further includes the step of returning part of air separated from the toner from the toner separating section to the toner storing section by using a returning fluid conveying mechanism. The toner replenishing unit of the present invention includes a returning fluid conveying mechanism between the toner storing section and the toner separating section.
    Type: Application
    Filed: January 21, 2003
    Publication date: July 31, 2003
    Inventors: Ritsuo Fujii, Seiji Yamaguchi, Hiroshi Isokawa
  • Patent number: 6381725
    Abstract: The storage unit of the present invention registers a plurality of data read conditions set in a plurality of parameters, an MPU reads data read conditions from the storage unit to an IC for read/write (R/W) in order and the MPU reads data from a magnetic disk according to these data read conditions. Then, a retry is repeated until normal data are obtained, the normal data are read, the frequency of data read conditions in the case where an error is recovered from, is accumulated, and the data read conditions are replaced when the accumulated value exceeds a certain threshold. By setting data read conditions whose probability of error recovery is high, in a higher order, the frequency of the retrying is reduced, and thereby a data error correction device and the correction method thereof can be provided such that data can be read from a magnetic disk in a short time.
    Type: Grant
    Filed: March 19, 1999
    Date of Patent: April 30, 2002
    Assignee: Fujitsu Limited
    Inventor: Hiroshi Isokawa
  • Patent number: 6301207
    Abstract: Disclosed is a servo gain compensating method for compensating a servo gain when in a seek operation and in a positioning process in an information storage device. The servo gain compensating method and a device thereof make compensation to a precise servo gain even when a temperature changes abruptly. The information storage device includes a head for reading information from a storage medium, an actuator for moving the head, a control circuit for calculating a drive quantity compensated by the servo gain value from positional information read by the head, and a driving circuit for driving the actuator on the basis of the drive quantity.
    Type: Grant
    Filed: December 11, 1998
    Date of Patent: October 9, 2001
    Assignee: Fujitsu Limited
    Inventors: Hiroshi Isokawa, Yukio Abe
  • Patent number: 6163425
    Abstract: In a magnetic reproduction apparatus having an MR head, electromigration occurs when a sense current is supplied to the MR head is suppressed, and the service life and reliability of the magnetic reproduction apparatus are improved. Information magnetically recorded on at least one recording medium is read by supplying a sense current to the MR head opposed to the record surface of the recording medium using a current supply circuit, and then decoded by a signal decoder. In the magnetic reproduction apparatus, an MR head information judgment circuit judges whether or not information to be read out from the recording medium by the MR head is needed. Only when the information to be read out by the MR head is needed, does a current supply control circuit allow the current supply circuit to supply the sense current to the MR head. The sense current can be controlled by turning on or off an on-off operation circuit.
    Type: Grant
    Filed: December 30, 1997
    Date of Patent: December 19, 2000
    Assignee: Fujitsu Limited
    Inventors: Hiroshi Isokawa, Yukio Abe