Patents by Inventor Shuji Hirai

Shuji Hirai 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: 9400442
    Abstract: An image forming apparatus includes a latent image carrier; a charger; a charging power supply; a latent image writer to write; a developing device; a rotary attitude sensor; a controller to perform a data formulating process to formulate a change pattern data and a bias changing process to cause the charging power supply to change the charging bias output based on readings from the rotary attitude sensor and the change pattern data, during a print job; and a surface potential sensor to detect a surface potential of the latent image carrier. In the data formulating process, the controller formulates the change pattern data based on the surface potential of the latent image carrier detected by the surface potential sensor, while the charging power supply outputting a constant charging bias, and based on readings from the rotary attitude sensor while the surface potential is being detected.
    Type: Grant
    Filed: July 17, 2015
    Date of Patent: July 26, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Satoshi Kaneko, Shinji Kato, Shuji Hirai
  • Publication number: 20160187807
    Abstract: An image forming apparatus includes an image forming section that includes a latent image bearer; a charger to charge a surface of the latent image bearer; and a latent image writer to write a latent image on the charged surface of the latent image bearer. The image forming apparatus further includes a developing device to develop the latent image with a developer borne on a developer bearer; and a cyclical changing device including a controller and a write controller, in combination. The cyclical changing device cyclically changes a developing bias to be applied to the developer bearer while cyclically changing a charge intensity of the charger during the image formation by the image forming section. The cyclical changing device cyclically changes the developing bias and the charge intensity, and a latent image write intensity of the latent image writer.
    Type: Application
    Filed: December 16, 2015
    Publication date: June 30, 2016
    Inventors: Shuji HIRAI, Satoshi KANEKO, Terumichi OCHI
  • Patent number: 9348288
    Abstract: An image forming apparatus includes a latent image bearer, a toner image forming unit, and a transfer device. The toner image forming unit includes a charger, a latent image forming device, and a developing device, and is configured to form a test latent image pattern on a surface of the latent image bearer, and to develop the test latent image pattern into a test toner pattern. The test latent image pattern includes a plurality of test latent image parts partly offset from one another in a main scanning direction. The image forming apparatus also includes a developing current detector and a processor to detect uneven image density in the main scanning direction using the test latent image pattern, based on the developing current detected by the developing current detector, to adjust the uneven image density in the main scanning direction.
    Type: Grant
    Filed: February 11, 2015
    Date of Patent: May 24, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Satoshi Kaneko, Shinji Kato, Shuji Hirai, Hideo Muroi, Terumichi Ochi
  • Publication number: 20160124367
    Abstract: An image forming apparatus that includes an imaging device, a transferrer, a rotator, a rotation position sensor, an adhesion amount sensor, a power supply, and a controller. The controller executes a construction process to construct output pattern data to change a voltage output from the power supply, according to a result obtained by detecting a toner adhesion amount of a toner image for density unevenness detection and a detection result from the rotation position sensor obtained when the toner image is formed, and an output change process to execute a predetermined process while changing the voltage according to the detection result and the output pattern data. The controller executes a determination process to determine propriety of an output range of the voltage output from the power supply by the output change process and a data process for a shift to shift the range when a determination result is inappropriate.
    Type: Application
    Filed: October 28, 2015
    Publication date: May 5, 2016
    Inventors: Satoshi KANEKO, Shuji HIRAI
  • Publication number: 20160062260
    Abstract: An image forming apparatus includes a latent image carrier; a charger; a charging power supply; a latent image writer to write; a developing device; a rotary attitude sensor; a controller to perform a data formulating process to formulate a change pattern data and a bias changing process to cause the charging power supply to change the charging bias output based on readings from the rotary attitude sensor and the change pattern data, during a print job; and a surface potential sensor to detect a surface potential of the latent image carrier. In the data formulating process, the controller formulates the change pattern data based on the surface potential of the latent image carrier detected by the surface potential sensor, while the charging power supply outputting a constant charging bias, and based on readings from the rotary attitude sensor while the surface potential is being detected.
    Type: Application
    Filed: July 17, 2015
    Publication date: March 3, 2016
    Inventors: Satoshi KANEKO, Shinji KATO, Shuji HIRAI
  • Patent number: 9250592
    Abstract: An image forming apparatus includes a storage to store recording media, a smoothness detector to detect smoothness of the recording media, a memory unit to store smoothness values detected by the smoothness detector, a transfer device to transfer a toner image onto the recording media, a fixing device to fix the toner image onto the recording media, a temperature controller to determine a target fixing temperature for a second and subsequent recording media based on a predicted value calculated from the smoothness values, and a processor to reset the smoothness values in response to detection of an external factor that causes the smoothness detector to provide a smoothness value out of a predetermined range of the predicted value during an image forming operation from when the processor receives a sheet-feeding permission signal of one of the recording media stored in the storage until the recording medium is ejected.
    Type: Grant
    Filed: January 8, 2015
    Date of Patent: February 2, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryota Yamashina, Keitaro Shoji, Shuji Hirai, Takumi Waida, Terumichi Ochi
  • Publication number: 20150362879
    Abstract: An image forming apparatus includes an image bearer; a toner image forming device; a transfer rotator; a transfer device; a rotation position detector; an image density detector; a density data acquisition unit to causes the toner image forming device to form an adjustment toner image equal to or greater in length than a circumferential length of the image bearer, cause a linear velocity difference between the image bearer and the transfer rotator in transfer of the adjustment toner image, and acquires, from a detected image density of the toner image transferred from the image bearer, detected by the image density detector, image density unevenness data with reference to detection of a reference rotation position of one of the image bearer and a rotator; and a correction unit to adjust an image forming condition according to the reference rotation position, the image density unevenness data, and the linear velocity difference.
    Type: Application
    Filed: June 1, 2015
    Publication date: December 17, 2015
    Inventors: Satoshi KANEKO, Shinji KATO, Shuji HIRAI
  • Patent number: 9188924
    Abstract: An image forming apparatus includes an image carrier; a developer carrier configured to adhere toner onto the image carrier; an image density detector to detect a density of an image on the image carrier formed by the developer carrier adhering the toner on the image carrier; a rotary member to form an image pattern of which density is detected by the image density detector; and a rotational position detector to detect a rotational position of the rotary member. In the image forming apparatus, the image pattern is generated based on the rotational position detected by the rotational position detector and the rotary member that the rotational position detector detects the rotational position thereof is either the image carrier or the developer carrier.
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: November 17, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Satoshi Kaneko, Shinji Kato, Hitoshi Ishibashi, Shuji Hirai, Jun Yamane, Koichi Kudo, Shingo Suzuki
  • Patent number: 9182720
    Abstract: In an image forming apparatus, a processor generates a first density variation data based on the surface potential of the pattern in relation to the rotational position of the image bearer and a second density variation data based on the first density variation data and the density of the toner pattern, stores the first density variation data and the second density variation data in a memory, makes a pattern in a predetermined timing, decides whether the first density variation data is changed or not, change the first density variation data based on the decision, controls the toner image forming condition of the toner image forming device based on the first density variation data and the second density variation data.
    Type: Grant
    Filed: August 22, 2012
    Date of Patent: November 10, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Satoshi Kaneko, Shinji Kato, Hitoshi Ishibashi, Shuji Hirai, Jun Yamane, Koichi Kudo, Shingo Suzuki
  • Patent number: 9152896
    Abstract: An image forming apparatus includes an image density detector, an image forming device, a rotator, an image density controller, and a timing correction data obtainer. The image density detector detects a toner density of an image formed on an image bearing member. An image forming device forms the image using a density adjustable element that adjusts the density of the image. The rotator forms an image pattern while the density adjustable element is changed, and a density thereof is detected by the image density detector. The image density controller controls the image forming device using a density correction data for the density adjustable element corresponding to a rotational period of the rotator. The timing correction data obtainer obtains timing correction data for correction of driving timing of the image forming device based on a change in the density of the image pattern detected by the image density detector.
    Type: Grant
    Filed: March 10, 2014
    Date of Patent: October 6, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Satoshi Kaneko, Shuji Hirai, Shinichi Akatsu, Shingo Suzuki, Tetsuya Muto, Keita Gotoh, Yuuichiroh Uematsu, Hitoshi Ishibashi
  • Patent number: 9141059
    Abstract: An image forming apparatus includes an image carrier, a rotation-position detector, a development device, a transfer unit, a density sensor, and an image-forming-condition determination unit. The density sensor senses a density of a toner image on a transfer body. The image-forming-condition determination unit forms an image pattern, acquires periodical density variation information sensed by the density sensor and detection information of the rotation-position detector, and determines an image forming condition based on the periodical density variation information and the detection information acquired. The image carrier and the transfer body are different in linear velocity in an image formation in which the toner image is transferred to a recording medium.
    Type: Grant
    Filed: March 11, 2014
    Date of Patent: September 22, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Tetsuya Muto, Shuji Hirai, Shinichi Akatsu, Shingo Suzuki, Satoshi Kaneko, Keita Gotoh, Yuuichiroh Uematsu
  • Publication number: 20150261162
    Abstract: An image forming apparatus includes a latent image bearer, a toner image forming unit, and a transfer device. The toner image forming unit includes a charger, a latent image forming device, and a developing device, and is configured to form a test latent image pattern on a surface of the latent image bearer, and to develop the test latent image pattern into a test toner pattern. The test latent image pattern includes a plurality of test latent image parts partly offset from one another in a main scanning direction. The image forming apparatus also includes a developing current detector and a processor to detect uneven image density in the main scanning direction using the test latent image pattern, based on the developing current detected by the developing current detector, to adjust the uneven image density in the main scanning direction.
    Type: Application
    Filed: February 11, 2015
    Publication date: September 17, 2015
    Inventors: Satoshi KANEKO, Shinji KATO, Shuji HIRAI, Hideo MUROI, Terumichi OCHI
  • Publication number: 20150261161
    Abstract: A recording media smoothness detector includes a sensor and a calculator. The sensor includes a light source to emit light toward a recording medium and a light-detecting device to detect an amount of light reflected by the recording medium. The calculator includes a first memory to store an initial output value of the sensor and a second memory to store a decreased output percentage of the sensor relative to the initial output value per number of recording media detected. The calculator is configured to calculate a decreased output amount of the sensor from the decreased output percentage of the sensor per number of recording media detected, according to number of recording media detected by the sensor, to adjust a luminosity of the sensor based on the calculated decreased output amount of the sensor and determine smoothness of the recording medium based on an output of the sensor after the adjustment.
    Type: Application
    Filed: March 10, 2015
    Publication date: September 17, 2015
    Inventors: Takumi WAIDA, Shuji HIRAI, Terumichi OCHI, Shinji KATO, Ryota YAMASHINA, Keitaro SHOJI
  • Patent number: 9128402
    Abstract: An image forming apparatus includes an image forming unit including rotary members to form a toner image corresponding to image data, in which the image forming unit forms a toner pattern for detecting image density fluctuation; and an image forming condition determination controller to perform image forming processing to ultimately transfer the toner image onto a recording medium. In the image forming apparatus, the controller measures a periodic image density fluctuation occurring in a rotation cycle of the rotary members based on a detection result of a toner pattern; performs image forming condition determination processing to determine an image forming condition to reduce the image density fluctuation based on measured image density fluctuation data; and determines whether or not the image density fluctuation data measured multiple times satisfies a predetermined control termination condition.
    Type: Grant
    Filed: December 13, 2013
    Date of Patent: September 8, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuuichiroh Uematsu, Shinichi Akatsu, Shuji Hirai, Shingo Suzuki, Tetsuya Muto, Satoshi Kaneko, Keita Goto
  • Publication number: 20150205241
    Abstract: An image forming apparatus includes a storage to store recording media, a smoothness detector to detect smoothness of the recording media, a memory unit to store smoothness values detected by the smoothness detector, a transfer device to transfer a toner image onto the recording media, a fixing device to fix the toner image onto the recording media, a temperature controller to determine a target fixing temperature for a second and subsequent recording media based on a predicted value calculated from the smoothness values, and a processor to reset the smoothness values in response to detection of an external factor that causes the smoothness detector to provide a smoothness value out of a predetermined range of the predicted value during an image forming operation from when the processor receives a sheet-feeding permission signal of one of the recording media stored in the storage until the recording medium is ejected.
    Type: Application
    Filed: January 8, 2015
    Publication date: July 23, 2015
    Inventors: Ryota YAMASHINA, Keitaro SHOJI, Shuji HIRAI, Takumi WAIDA, Terumichi OCHI
  • Patent number: 9052663
    Abstract: An image forming apparatus includes an image carrier; an image forming unit; a processor for controlling the image forming unit according to a predetermined image forming condition setting data; an image density sensor to detect an image density of the toner pattern formed on the image carrier; a reference rotary position detector; an image density fluctuation data acquisition unit to obtain an image density fluctuation data of more than one circumferential length of the photoreceptor drum with reference to the reference rotary position detected by the reference rotary position detector based on a result related to the toner pattern formed on the image carrier detected by the image density sensor; and a correction data generator to generate a correction data to correct a reference image forming condition setting data with a correction amount corresponding to each rotary position of the rotary member to thus reduce the image density fluctuation.
    Type: Grant
    Filed: March 27, 2014
    Date of Patent: June 9, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Shingo Suzuki, Satoshi Kaneko, Shuji Hirai, Koichi Kudo, Jun Yamane, Shinji Kato
  • Patent number: 9046850
    Abstract: In an image forming apparatus, a first controller forms a first image pattern on an image bearer and determines a first image formation condition based on a detection result of density of a toner image. The first controller then controls a toner image forming device based on the first image formation condition. A second controller forms a second image pattern different from the first image pattern on an image bearer and determines a second image formation condition based on a detection result of density of a toner image. The second controller then controls a toner image forming device based on the second image formation condition.
    Type: Grant
    Filed: January 30, 2012
    Date of Patent: June 2, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Shuji Hirai, Satoshi Kaneko, Shinji Kato, Jun Yamane, Koichi Kudo, Shingo Suzuki
  • Publication number: 20150116718
    Abstract: An optical sensor includes a light-emitting unit to emit light onto a measuring object, a regular reflection light receiver to receive regular reflection light from the measuring object out of the light emitted by the light-emitting unit, and a diffuse reflection light receiver to receive diffuse reflection light from the measuring object out of the light emitted by the light-emitting unit. An angle of incidence of the light emitted onto a surface of the measuring object is not smaller than 75° and not larger than 85°. The diffuse reflection light receiver receives, out of the diffuse reflection light from the measuring object, diffuse reflection light having an angle of reflection with respect to a perpendicular to the surface of the measuring object larger than 0° and smaller than an angle of reflection of the regular reflection light with respect to the perpendicular to the surface of the measuring object.
    Type: Application
    Filed: October 13, 2014
    Publication date: April 30, 2015
    Inventors: Terumichi OCHI, Takumi WAIDA, Shinji KATO, Toshihiro ISHII, Shuji HIRAI, Takashi FUJITA, Shinichi NAMEKATA, Ryota YAMASHINA, Arinobu YOSHIURA, Motoyoshi YAMANO
  • Patent number: 8998628
    Abstract: A fixed-side ring plate rotation regulation section is provided at an outer circumferential edge of a fixed-side ring plate, and an outer cylinder rotation regulation section is provided at an outer circumferential edge of an outer cylinder at a position corresponding to the fixed-side ring plate rotation regulation section. The fixed-side ring plate and the outer cylinder formed of different members from each other are fit to each other such that the fixed-side ring plate rotation regulation section and the outer cylinder rotation regulation section are in contact with each other so as not to rotate about a rotation axis thereof.
    Type: Grant
    Filed: May 20, 2013
    Date of Patent: April 7, 2015
    Assignees: Furukawa Electric Co., Ltd., Furukawa Automotive Systems Inc.
    Inventor: Shuji Hirai
  • Publication number: 20150078770
    Abstract: An image forming apparatus includes paper trays to contain and feed a recording sheet on which a toner image is transferred; status sensors to detect a storage status of the recording sheet contained in the paper trays; a sheet sensor to detect a smoothness of the recording sheet; a memory to store detection values of the smoothness detected by the sheet sensor; a fixing device to heat and press the toner image transferred onto the recording sheet and fix it onto the recording sheet; and a control circuit to determine a target fixing temperature of the fixing device based on the detection values stored in the memory. The control circuit determines the target fixing temperature for successive recording sheets depending on the detected smoothness, and resets the detection values stored in the memory to zero when the status sensors detect a change in the storage status of the paper trays.
    Type: Application
    Filed: September 2, 2014
    Publication date: March 19, 2015
    Inventors: Motoyoshi YAMANO, Shinichi Namekata, Ryota Yamashina, Takumi Waida, Shinji Kato, Shuji Hirai, Terumichi Ochi