Patents by Inventor Yoshihisa Ashikawa

Yoshihisa Ashikawa 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).

  • Patent number: 8781358
    Abstract: An image forming apparatus includes a developing unit configured to supply a toner onto a surface of an image carrier to form a toner image carried from a toner container; a transfer unit configured to transfer the toner image onto a transfer medium; a cleaning unit configured to collect a non-transferred toner that is not transferred onto the transfer medium during the transfer by the transfer unit; a recycle unit configured to carry the non-transferred toner to the developing unit; a non-transferred-toner-amount detecting unit configured to detects an amount of the non-transferred toner; a total-toner-amount calculating unit configured to calculates an amount of the toner carried from the toner container; a consumed-toner-amount calculating unit configured to calculate, based on the amounts, a consumed toner amount; and an environmental-load-information calculating unit configured to calculate, based on the consumed toner amount, environmental load information.
    Type: Grant
    Filed: February 21, 2012
    Date of Patent: July 15, 2014
    Assignee: Ricoh Company, Limited
    Inventor: Yoshihisa Ashikawa
  • Patent number: 8743384
    Abstract: An image forming apparatus is provided with a processing unit that performs a predetermined process, a power-supply shutting unit that shuts off power supply to the processing unit when a predetermined door is opened, a voltage detecting unit that detects a decrease in voltage at a point located posterior to the power-supply shutting unit, and a communication control unit that does not initiate communication with the processing unit if the decrease in voltage is detected by the voltage detecting unit before a start of the communication with the processing unit, and judges the just-ended communication as abnormal if the decrease in voltage is detected by the voltage detecting unit after the end of the communication with the processing unit.
    Type: Grant
    Filed: September 14, 2011
    Date of Patent: June 3, 2014
    Assignee: Ricoh Company, Limited
    Inventors: Tatsuya Ishii, Yoshihisa Ashikawa
  • Patent number: 8368251
    Abstract: There is provided an image forming apparatus includes: a first electric-power supply path, through which electric power is supplied from a commercial electric power supply to the apparatus when the first electric-power supply path is in closed state; a second electric-power supply path, through which electric power is supplied from the commercial electric power supply to the apparatus when, at least, a detecting unit has detected that the first electric-power supply path is in the open state; and a plurality of drive-voltage generating units, each of which converts a voltage fed from the electric power supply through any one of the first electric-power supply path and the second electric-power supply path into a predetermined drive voltage; a plurality of systems, to each of which the drive voltage converted by a corresponding one drive-voltage generating unit of the drive-voltage generating units is fed.
    Type: Grant
    Filed: August 3, 2010
    Date of Patent: February 5, 2013
    Assignee: Ricoh Company, Limited
    Inventor: Yoshihisa Ashikawa
  • Publication number: 20120213543
    Abstract: An image forming apparatus includes a developing unit configured to supply a toner onto a surface of an image carrier to form a toner image carried from a toner container; a transfer unit configured to transfer the toner image onto a transfer medium; a cleaning unit configured to collect a non-transferred toner that is not transferred onto the transfer medium during the transfer by the transfer unit; a recycle unit configured to carry the non-transferred toner to the developing unit; a non-transferred-toner-amount detecting unit configured to detects an amount of the non-transferred toner; a total-toner-amount calculating unit configured to calculates an amount of the toner carried from the toner container; a consumed-toner-amount calculating unit configured to calculate, based on the amounts, a consumed toner amount; and an environmental-load-information calculating unit configured to calculate, based on the consumed toner amount, environmental load information.
    Type: Application
    Filed: February 21, 2012
    Publication date: August 23, 2012
    Inventor: Yoshihisa ASHIKAWA
  • Publication number: 20120062929
    Abstract: An image forming apparatus is provided with a processing unit that performs a predetermined process, a power-supply shutting unit that shuts off power supply to the processing unit when a predetermined door is opened, a voltage detecting unit that detects a decrease in voltage at a point located posterior to the power-supply shutting unit, and a communication control unit that does not initiate communication with the processing unit if the decrease in voltage is detected by the voltage detecting unit before a start of the communication with the processing unit, and judges the just-ended communication as abnormal if the decrease in voltage is detected by the voltage detecting unit after the end of the communication with the processing unit.
    Type: Application
    Filed: September 14, 2011
    Publication date: March 15, 2012
    Inventors: Tatsuya Ishii, Yoshihisa Ashikawa
  • Patent number: 8081894
    Abstract: When a user has performed an operation with respect to an image forming apparatus, a control mechanism informs that a user has performed an operation with respect to an image forming apparatus to an engine control unit through a dedicated communication line, i.e., without waiting for a general-purpose communication line to open for communication. Upon receiving the user operation signal, the engine control unit heats a fixing unit.
    Type: Grant
    Filed: June 25, 2008
    Date of Patent: December 20, 2011
    Assignee: Ricoh Company, Limited
    Inventors: Yoshihisa Ashikawa, Keiichi Sanada
  • Publication number: 20110031807
    Abstract: There is provided an image forming apparatus includes: a first electric-power supply path, through which electric power is supplied from a commercial electric power supply to the apparatus when the first electric-power supply path is in closed state; a second electric-power supply path, through which electric power is supplied from the commercial electric power supply to the apparatus when, at least, a detecting unit has detected that the first electric-power supply path is in the open state; and a plurality of drive-voltage generating units, each of which converts a voltage fed from the electric power supply through any one of the first electric-power supply path and the second electric-power supply path into a predetermined drive voltage; a plurality of systems, to each of which the drive voltage converted by a corresponding one drive-voltage generating unit of the drive-voltage generating units is fed.
    Type: Application
    Filed: August 3, 2010
    Publication date: February 10, 2011
    Inventor: Yoshihisa ASHIKAWA
  • Patent number: 7853164
    Abstract: A plurality of heating units generates a heat by an alternating-current power supplied from a corresponding alternating-current power supply unit through a corresponding input terminal and supplying the heat to a fixing unit that fixes a toner image transformed on a recording paper by heating. A plurality of power control units controls the alternating-current power to a corresponding heating unit. A plurality of detecting units detects a reference phase of waveform of the alternating-current power. A control unit individually controls the power control units based on detected signals output from the detecting units.
    Type: Grant
    Filed: September 10, 2007
    Date of Patent: December 14, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiichi Sanada, Takeshi Sano, Yoshihisa Ashikawa, Naoki Sato, Tomonori Maekawa
  • Patent number: 7659726
    Abstract: An image forming apparatus includes two AC power input cords to be connected to an AC power source. The image forming apparatus can detect if at least one of the two AC power input cords is not connected to the AC power source. An input voltage detector or a zero-cross signal detector receives an input from the one AC input power cord, and detects a voltage state of connection to the AC power input cord. A controller utilizes signals from the input voltage detector or zero-cross signal detector to detect whether the one AC input power cord is connected to the AC power source. An operator can also be provided an indication if it is determined that the one AC power input cord is not connected to the AC power source.
    Type: Grant
    Filed: August 30, 2007
    Date of Patent: February 9, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Naoki Satoh, Keiichi Sanada, Takeshi Sano, Yoshihisa Ashikawa, Tomonori Maekawa
  • Patent number: 7574152
    Abstract: An AC high-voltage device includes a voltage controlling unit that controls an AC transforming unit. The AC transforming unit transforms supplied power to an AC high voltage. The voltage controlling unit includes a constant-voltage controlling unit and an turn-off unit. The constant-voltage controlling unit controls the AC transforming unit when an over-current does not occur in the AC high voltage. The turn-off unit turns off the AC transforming unit during a period in which an over-correct occurs. The constant-voltage controlling unit re-starts the AC transforming unit after the period.
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: August 11, 2009
    Assignee: Ricoh Company, Limited
    Inventor: Yoshihisa Ashikawa
  • Publication number: 20090016759
    Abstract: When a user has performed an operation with respect to an image forming apparatus, a control mechanism communicates informs the fact that a user has performed an operation with respect to an image forming apparatus to an engine control unit through a dedicated communication line, i.e., without waiting for a general-purpose communication line to open for communication. Upon receiving the user operation signal, the engine control unit heats a fixing unit.
    Type: Application
    Filed: June 25, 2008
    Publication date: January 15, 2009
    Inventors: Yoshihisa Ashikawa, Keiichi Sanada
  • Publication number: 20080069584
    Abstract: A plurality of heating units generates a heat by an alternating-current power supplied from a corresponding alternating-current power supply unit through a corresponding input terminal and supplying the heat to a fixing unit that fixes a toner image transformed on a recording paper by heating. A plurality of power control units controls the alternating-current power to a corresponding heating unit. A plurality of detecting units detects a reference phase of waveform of the alternating-current power. A control unit individually controls the power control units based on detected signals output from the detecting units.
    Type: Application
    Filed: September 10, 2007
    Publication date: March 20, 2008
    Inventors: Keiichi Sanada, Takeshi Sano, Yoshihisa Ashikawa, Naoki Sato, Tomonori Maekawa
  • Publication number: 20080054878
    Abstract: An image forming apparatus includes two AC power input cords to be connected to an AC power source. The image forming apparatus can detect if at least one of the two AC power input cords is not connected to the AC power source. An input voltage detector or a zero-cross signal detector receives an input from the one AC input power cord, and detects a voltage state of connection to the AC power input cord. A controller utilizes signals from the input voltage detector or zero-cross signal detector to detect whether the one AC input power cord is connected to the AC power source. An operator can also be provided an indication if it is determined that the one AC power input cord is not connected to the AC power source.
    Type: Application
    Filed: August 30, 2007
    Publication date: March 6, 2008
    Inventors: Naoki Satoh, Keiichi Sanada, Takeshi Sano, Yoshihisa Ashikawa, Tomonori Maekawa
  • Publication number: 20070098419
    Abstract: An AC high-voltage device includes a voltage controlling unit that controls an AC transforming unit. The AC transforming unit transforms supplied power to an AC high voltage. The voltage controlling unit includes a constant-voltage controlling unit and an turn-off unit. The constant-voltage controlling unit controls the AC transforming unit when an over-current does not occur in the AC high voltage. The turn-off unit turns off the AC transforming unit during a period in which an over-correct occurs. The constant-voltage controlling unit re-starts the AC transforming unit after the period.
    Type: Application
    Filed: October 27, 2006
    Publication date: May 3, 2007
    Inventor: Yoshihisa ASHIKAWA
  • Patent number: 6829444
    Abstract: An image forming apparatus includes a photoconductive drum, a charging roller to charge the photoconductive drum, a thermistor to detect an ambient temperature of the photoconductive drum. A ROM stores impedance characteristics data that is obtained in advance by experiments and that represent a relationship between the ambient temperature of the photoconductive drum and an impedance between the charging roller and the photoconductive drum. Current ambient temperature of the photoconductive drum detected, current impedance between the charging roller and the photoconductive drum is calculated from the current ambient temperature of the photoconductive drum and the impedance characteristics data, and a voltage applied to the charging roller is adjusted based on the current impedance.
    Type: Grant
    Filed: July 2, 2003
    Date of Patent: December 7, 2004
    Assignee: Ricoh Company, Limited
    Inventor: Yoshihisa Ashikawa
  • Publication number: 20040037576
    Abstract: An image forming apparatus includes a photoconductive drum, a charging roller to charge the photoconductive drum, a thermistor to detect an ambient temperature of the photoconductive drum. A ROM stores impedance characteristics data that is obtained in advance by experiments and that represent a relationship between the ambient temperature of the photoconductive drum and an impedance between the charging roller and the photoconductive drum. Current ambient temperature of the photoconductive drum detected, current impedance between the charging roller and the photoconductive drum is calculated from the current ambient temperature of the photoconductive drum and the impedance characteristics data, and a voltage applied to the charging roller is adjusted based on the current impedance.
    Type: Application
    Filed: July 2, 2003
    Publication date: February 26, 2004
    Inventor: Yoshihisa Ashikawa