Patents by Inventor Yuuji Sawai

Yuuji Sawai 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: 20030086733
    Abstract: An image forming apparatus of the present invention includes an intermediate transfer belt to which a toner image is transferred from an image carrier. A transfer roller contacts the intermediate transfer belt, forming a nip for image transfer. The transfer roller causes the toner image to be transferred from the intermediate transfer belt to a recording medium at the nip. A first and a second guide member cooperate to guide the recording medium to the nip. The end of the second guide member is positioned at the intermediate transfer belt side with respect to a line connecting a restriction point included in the first guide member and the inlet of the nip. This configuration causes a portion of the recording medium rearward of a portion entered the nip to bend in a convex configuration. The recording medium therefore surely remains in close contact with the intermediate transfer belt in a region where pretransfer is apt to occur.
    Type: Application
    Filed: November 29, 2002
    Publication date: May 8, 2003
    Inventors: Yuuji Sawai, Toshiaki Motohashi
  • Publication number: 20030035660
    Abstract: An image forming apparatus comprises a latent image support which supports an electrostatic latent image. A charging unit charges a surface of the image support. A latent image formation unit forms an electrostatic latent image on the image support surface. A developing unit develops the latent image with toner to form a toner image. A transfer unit transfers the toner image from the image support to a recording medium. A ransnsport unit transports the recording medium so that the image support surface is countered to a surface of the recording medium. The surface of the image support has a coefficient of friction ranging from 0.1 to 0.7 according to Euler belt method, and a difference between a speed of the image support and a speed of the recording medium is below 1%, and the image support has an outermost surface containing a filler and a binder resin.
    Type: Application
    Filed: June 25, 2002
    Publication date: February 20, 2003
    Inventors: Akihiro Sugino, Yuuji Sawai, Mitsuru Takahashi, Kohki Katoh, Katsuya Kawagoe, Hiromi Ogiyama, Takahiro Tamiya
  • Publication number: 20030026625
    Abstract: In an electrophotographic image forming apparatus of the type including a plurality of image carriers arranged along an image transfer belt and an image transferring device configured to transfer toner images of different colors from the image carriers to a sheet being conveyed by an image transfer belt or by way of the image transfer belt by applying a bias to the belt, a bias applying method of the present invention can measure a current leaking between a plurality of high-tension power supply sections or to the ends thereof as AC resistances between respective terminals and therefore to accurately measure the leak currents of DC components. Therefore, when relatively high DC components are selected, a difference in current between a plurality of power supply sections can be maintained constant.
    Type: Application
    Filed: July 23, 2002
    Publication date: February 6, 2003
    Inventors: Takahiro Tamiya, Akihiro Sugino, Hiromi Ogiyama, Katsuya Kawagoe, Kohki Katoh, Mitsuru Takahashi, Yuuji Sawai
  • Patent number: 6516179
    Abstract: An image forming apparatus of the present invention includes an intermediate transfer belt to which a toner image is transferred from an image carrier. A transfer roller contacts the intermediate transfer belt, forming a nip for image transfer. The transfer roller causes the toner image to be transferred from the intermediate transfer belt to a recording medium at the nip. A first and a second guide member cooperate to guide the recording medium to the nip. The end of the second guide member is positioned at the intermediate transfer belt side with respect to a line connecting a restriction point included in the first guide member and the inlet of the nip. This configuration causes a portion of the recording medium rearward of a portion entered the nip to bend in a convex configuration. The recording medium therefore surely remains in close contact with the intermediate transfer belt in a region where pretransfer is apt to occur.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: February 4, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuuji Sawai, Toshiaki Motohashi
  • Publication number: 20030016969
    Abstract: An image forming apparatus of the present invention includes a plurality of image forming means each including an image carrier, a charger for uniformly charging the surface of said image carrier, and a developing device for developing a latent image formed on the charged surface of the image carrier with toner to thereby produce a corresponding toner image. A primary image transferring device transfers such toner images from the image carriers to an intermediate image transfer body one above the other, thereby completing a composite toner image. A secondary image transferring device transfers the composite toner image from the intermediate image transfer body to a recording medium. The primary image transferring device includes the intermediate image transfer body including at least an elastic layer, a cleaning unit for cleaning the intermediate image transfer body, and a coating member for coating a lubricant on the intermediate image transfer body.
    Type: Application
    Filed: July 12, 2002
    Publication date: January 23, 2003
    Inventor: Yuuji Sawai
  • Publication number: 20030016968
    Abstract: An image forming apparatus of the present invention includes a cleaning device for cleaning an intermediate image transfer body. A cleaning blade included in the image transfer body is formed of fluorocarbon resin or a thin layer of fluorocarbon resin is formed on the surface of the intermediate image transfer body. Further, wax is coated on the intermediate image transfer body or wax or lubricant powder is contained in toner. A moving mechanism holds the cleaning blade spaced from the intermediate image transfer body at least when image formation is not under way.
    Type: Application
    Filed: July 12, 2002
    Publication date: January 23, 2003
    Inventors: Mitsuru Takahashi, Yuuji Sawai, Hiromi Ogiyama, Katsuya Kawagoe, Akihiro Sugino, Kohki Katoh
  • Publication number: 20020051664
    Abstract: Monocolor image forming unit includes a developing device and an image carrier cleaning device arranged around an image carrier. A plurality of such the monocolor image forming unit is arrayed laterally along the rotary transport direction of an intermediate transfer member of the belt type to configure a tandem image forming device. In the tandem image forming device, a synthesized toner image is formed on the intermediate transfer member and transferred to a recording medium to form a multicolor image thereon. Among the plurality of monocolor image forming unit contained in the tandem image forming device, at least two monocolor image forming unit each include a toner recycling device for conveying toner collected at the image carrier cleaning device to the developing device.
    Type: Application
    Filed: September 25, 2001
    Publication date: May 2, 2002
    Inventors: Katsuhiro Aoki, Tsumori Satoh, Misao Tanzawa, Yuuji Sawai, Mitsuru Takahashi, Hajime Oyama, Sadayuki Iwai, Tohru Nakano
  • Publication number: 20020034406
    Abstract: An image forming apparatus including a belt guide member fixedly provided at an upstream side of a nip formed between a roller and a transfer roller so the belt guide member protrudes an image bearing belt such that the belt is substantially parallel with a conveying direction of a transfer medium.
    Type: Application
    Filed: September 7, 2001
    Publication date: March 21, 2002
    Applicant: RICOH COMPANY, LTD.
    Inventors: Katsuya Kawagoe, Toshiaki Motohashi, Yuuji Sawai, Shin Kayahara, Ryuta Takeichi, Mitsuru Takahashi, Hiroshi Ono, Hiromi Ogiyama