Patents by Inventor Akira Tamagaki

Akira Tamagaki 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: 5298942
    Abstract: An image forming apparatus includes a drum having a hollow polyhedron cylinder of which facets have windows. A liquid crystal cell is attached to each window of the drum for receiving image light from out side the drum on the one surface thereof to pick up a document image therein, and for receiving second light on the back surface thereof inside the drum to cause the image to be read out. The drum is rotated so that the liquid crystal cell provided on each window of the drum can sequentially receive first light reflected by the document on the one surface thereof out side the drum and second light irradiated by a second irradiating device on the back surface thereof inside the drum. A photoreceptor for receiving second light reflected by the back surface of the liquid crystal cell forms an electrostatic latent image corresponding to a document image, which is developed, transferred onto a copy paper and fixed.
    Type: Grant
    Filed: September 30, 1992
    Date of Patent: March 29, 1994
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshiaki Ibuchi, Akira Tamagaki, Naoyuki Kamei, Yoshigumi Maitani
  • Patent number: 5160960
    Abstract: In a method of transporting a photosensitive sheet for image forming operation, the photosensitive sheet is transported forward through an exposure section where a latent image is formed thereon, and then through a pressure-developing section where the photosensitive sheet is pressed against an image receiving sheet to develop the latent image and form a visible image on the image receiving sheet. In this pressure-developing process, the length of the photosensitive sheet which is drawn out from the sheet-feeding rod is measured. Then, the photosensitive sheet is further transported forward until the image receiving sheet is separated therefrom. Thereafter, the photosensitive sheet is transported backward by the length measured in the pressure-developing process.
    Type: Grant
    Filed: May 14, 1991
    Date of Patent: November 3, 1992
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshiaki Ibuchi, Akira Tamagaki
  • Patent number: 5084627
    Abstract: A sheet detecting device has a pair of first and second reflection type photosensors in both sides of upper and lower guide members of a sheet carrying path. A reflector member is disposed in the lower guide member facing to the first reflection type photosensor and a comparator for comparing the output signal of the first reflection type photosensor with a predetermined reference value which is used when an image receiving sheet is not fed in the sheet detecting device. The difference between the reflectances of the right side and wrong side of the sheet fed in the sheet detecting device is detected by the first and second reflection type photosensors, so that information of the image receiving sheet is obtained.
    Type: Grant
    Filed: May 15, 1990
    Date of Patent: January 28, 1992
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshiharu Ueki, Fumio Shimazu, Akira Tamagaki
  • Patent number: 5077574
    Abstract: An image forming apparatus which has a plurality of exposing optical systems used singly or jointly depending upon when an image is to be formed from different kinds of documents such as one is non-transmissive and the other is transmissive, or when a synthetic image is to be formed from different kinds of documents.
    Type: Grant
    Filed: December 28, 1990
    Date of Patent: December 31, 1991
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Akira Tamagaki, Shougo Iwai
  • Patent number: 5070360
    Abstract: A copying machine which projects a light image from different documents placed at different places onto the same exposure section in the photosensitive material along the respective different optical axes, thereby facilitating the changeover of the documents with the initially set optical axes being kept.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: December 3, 1991
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Akira Tamagaki, Shougo Iwai
  • Patent number: 5003344
    Abstract: A projection unit, which is mounted in a copying machine and used to project an image of a light permeable original onto a prescribed exposure point on a photosensitive material, comprising a light source for exposure in a box, an original holding means which holds the original in a prescribed position with respect to the light source and the photosensitive material and is disposed movably in the box so that the image of the original is scanned in a prescribed direction with respect to the photosensitive material, a driving means for moving the original holding means in the scanning direction, a transmission means provided between the original holding means and the driving means which is capable of moving between an engaged position in that the transmission means is coupled to the original holding means and driving means so as to transmit power of the driving means to the holding means and a disengaged position in that the transmission means is not coupled to the original holding means and the driving means,
    Type: Grant
    Filed: April 9, 1990
    Date of Patent: March 26, 1991
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshiaki Ibuchi, Mitsuru Ogura, Akira Tamagaki, Shougo Iwai
  • Patent number: 4594536
    Abstract: A servomotor speed control system includes a ROM table which stores a minimum distance suited for each motor speed. When the minimum distance corresponding to the current motor speed becomes shorter than the current distance from the current motor position to a positioning target point, the instructed speed is reduced to decelerate the servomotor rotation. In a preferred form, the unit of the distance is identical with an interval of a position indicating signal developed from a rotary encoder associated with the servomotor.
    Type: Grant
    Filed: July 12, 1984
    Date of Patent: June 10, 1986
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Akira Tamagaki