Patents Assigned to Mita Industrial Company
  • Patent number: 4511241
    Abstract: A copying apparatus capable of performing a first preset number of copying operations corresponding to a first original document in a successive copying operation mode, and performing a second preset number of copying operations corresponding to a second original document in an intruded copying operation mode includes preset number display elements for indicating a first and second preset numbers, first counter for counting a number of copying operations, a copy number display element for indicating a value counted by the first counting means, a second counter for counting a discharged copy paper after the completion of a copying operation, and a detector for detecting a jam of the copy paper. The counted value of the first counter is revised so as to be equal to the counted value of the second counter when a copy paper jam occurs.
    Type: Grant
    Filed: July 21, 1982
    Date of Patent: April 16, 1985
    Assignee: Mita Industrial Company Limited
    Inventors: Hideaki Tsudaka, Takaji Washio, Nobuhiko Kozuka, Masahide Iseki, Toshio Watanabe, Masami Kai, Toshio Yoshiyama, Hiromi Sakata
  • Patent number: 4502779
    Abstract: A cleaning device for use in an electrostatic copying machine removes with a blade any residual toner from a photosensitive body after a toner image has been transferred therefrom to a sheet of copying paper. A support shaft supports the blade for slidable contact with the photosensitive body and has a horizontal axis extending perpendicularly to a direction of travel of the photosensitive body. The support shaft is angularly movable about the axis and is axially movable. A rotational shaft is rotatable about an axis parallel to the support shaft. A first device converts rotational movement of the rotational shaft into reciprocal movement along the axis of the support shaft. A second device converts rotational movement of the rotational shaft into reciprocal angular movement of the support shaft. A third device releases interconnection between the rotational shaft and the first and second devices.
    Type: Grant
    Filed: November 16, 1982
    Date of Patent: March 5, 1985
    Assignee: Mita Industrial Company Limited
    Inventors: Hiroshi Kajita, Tadanobu Nakajima, Masahide Iseki
  • Patent number: 4501485
    Abstract: A card-operated copying machine allows copying operation in response to insertion of one, at a time, of key checking cards for supervising copy counts for a plurality of sections. The card-operated copying machine includes (a) key checking cards assigned respectively to the sections, (b) a processor for issuing a signal capable of copying operation, the processor having a random-access memory for storing total copy counts respectively for the sections with flags indicative of permission and inhibition of copying operation, (c) a copy count display for reading the data stored in the random-access memory and displaying the total copy count for each section, and (d) an inhibition card recording thereon information for setting the flags to an inhibition state. The copying operation is permitted and inhibited in response to the flag conditions.
    Type: Grant
    Filed: April 19, 1983
    Date of Patent: February 26, 1985
    Assignee: Mita Industrial Company Limited
    Inventor: Hideaki Tsudaka
  • Patent number: 4502067
    Abstract: Disclosed is a heat-sensitive recording material capable of forming an image of a hue close to a pure black at a low density, which comprises a dispersion of a leuco dye, a heat-fusible organic acidic substance solid at normal temperature and a sensitizing agent in a binder, wherein the leuco dye comprises a fluoran type leuco dye for forming a black color and a benzofluoran type leuco dye for forming a red dye in an amount of 0.01 to 1% by weight based on said black color-forming leuco dye.
    Type: Grant
    Filed: June 29, 1983
    Date of Patent: February 26, 1985
    Assignee: Mita Industrial Company Limited
    Inventors: Masanori Matsuda, Haruo Koyama, Nobuhiro Miyakawa
  • Patent number: 4484734
    Abstract: A copy paper feeding device for a copying apparatus includes a plurality of cassettes which are capable of storing copy paper sheets and a feeder which respectively corresponds to each of the cassettes. Each feeder is selectively driven so as to feed the copy paper sheets in the case where the cassettes store copy paper sheets having different sizes and each feeder is driven in a predetermined order so as to feed the copy paper sheets from one cassette until the cassette is empty and then successively feed the copy paper sheets from the remaining cassette in the case where the cassettes store copy paper sheets having the same size. The copy paper feeding device includes a selector for selecting which feeder is to be driven.
    Type: Grant
    Filed: July 21, 1982
    Date of Patent: November 27, 1984
    Assignee: Mita Industrial Company Limited
    Inventors: Hideaki Tsudaka, Takaji Washio, Nobuhiko Kozuka, Masahide Iseki, Toshio Watanabe, Masami Kai, Toshio Yoshiyama, Hiromi Sakata
  • Patent number: 4485163
    Abstract: A one-component magnetic dry developer for use in development of positively charged images and transfer of developed images, comprises particles of a composition comprising a vinyl aromatic polymer, an aliphatic carboxylic acid having at least 14 carbon atoms, inclusive of the carbon atom of the carboxyl group, per carboxyl group or its metal salt and a finely divided magnetic material having a coercive force not larger than 120 Oe and a bulk density of at least 0.45 g/ml.This magnetic developer provides an excellent transferred image having high image density and image sharpness on a plain paper as a transfer sheet without fogging or broadening of the contour of the image.
    Type: Grant
    Filed: June 2, 1982
    Date of Patent: November 27, 1984
    Assignee: Mita Industrial Company Limited
    Inventor: Nobuhiro Miyakawa
  • Patent number: 4481275
    Abstract: A mass of residual charged toner is blocked by a blade member held in slidable engagement with a photosensitive member against movement therewith toward a development roller when an image is being formed on the photosensitive member. When no image is being formed thereon, the blade member is lifted off the photosensitive member to allow the mass of residual toner to move therewith toward the development roller. During this time, a bias potential having a polarity the same as that of the toner is applied to members of an electrostatic or electrographic copying machine located between the blade member and the development roller for repelling the mass of toner toward the photosensitive member against being scattered off the latter and hence smearing surrounding parts.
    Type: Grant
    Filed: January 19, 1983
    Date of Patent: November 6, 1984
    Assignee: Mita Industrial Company Ltd.
    Inventors: Masahide Iseki, Tadanobu Nakajima, Hiroshi Kajita, Masuo Kawamoto
  • Patent number: 4478506
    Abstract: An electrostatic copying apparatus wherein a stationary original document image is projected onto a photosensitive member during movement of an optical device for exposing, and an electrostatic latent image formed on the photosensitive member is transferred onto a copy sheet and is fixed, comprising (a) a jam detecting means for immediately detecting a copy sheet being jammed on a transport path; and (b) a cleaning device for removing residual toner particles remaining on the photosensitive member by means of magnetic force and for storing the removed toner particles after transferring operation. According to this invention, an occurrence of jam is detected immediately, and thus a fault or an accident of the electrostatic copying apparatus due to jam is prevented from expanding.
    Type: Grant
    Filed: February 4, 1983
    Date of Patent: October 23, 1984
    Assignee: Mita Industrial Company Limited
    Inventors: Yoshitake Miyoshi, Kiyoshi Shibata, Toshio Watanabe, Masami Kai, Yousuke Ohata
  • Patent number: 4478507
    Abstract: A support mount for the rotary drum of an electrostatic copying apparatus. A pair of guide and support members is positioned within the copier housing, spaced from each other a predetermined distance in the direction of the central axis of the drum. Each guide and support member has a shaft support opening with a recess extending substantially perpendicular to the drum axis and a main guide surface extending from the lower end of the recess away from the shaft support opening and substantially perpendicular to the drum axis. When the peripheral surfaces of the drum bearing members are moved along the main guide surfaces, each bearing member passes through the respective recess and is positioned within the respective support opening. A pair of projecting pieces are positioned at the side plates of a frame of the copying apparatus developing device.
    Type: Grant
    Filed: February 8, 1983
    Date of Patent: October 23, 1984
    Assignee: Mita Industrial Company Limited
    Inventors: Hideo Miyoshi, Tadashi Umeda, Takashi Aoki
  • Patent number: 4477173
    Abstract: A toner replenishing device for replenishing toner to a developing device in an electrostatic copying apparatus includes a storing box extending in approximately a horizontal direction, a supply roller provided at a supply port at an end of the storing box, pairs of wheels respectively provided at opposite ends of the storing box, a pair of endless stretched members passed around the wheels, a stirring and supply rod provided between the endless stretched members, and a device for driving the wheels so as to move the lower portion of the endless stretched members toward the supply roller.
    Type: Grant
    Filed: June 30, 1982
    Date of Patent: October 16, 1984
    Assignee: Mita Industrial Company Limited
    Inventors: Nobuhiko Kozuka, Shigeo Koyama, Masami Kai, Ichiro Takahashi, Hiromi Sakata, Atsushi Kano
  • Patent number: 4468111
    Abstract: An electrostatic copying machine apparatus includes a developing device having a fixedly positioned permanent magnet and a hollow developing sleeve formed of a non-magnetic material mounted coaxially about the permanent magnet for rotation thereabout. Toner supplied to the periphery of the sleeve forms thereon a magnetic brush which is conveyed by rotation of the sleeve to a developing position whereat the toner is transferred to a photoreceptor as a visible toner image. A bristle cutting member is positioned upstream of the developing position to restrict the length of the magnetic brush. A blade member formed of a non-magnetizable material prevents solidification of the toner on the periphery of the sleeve and is positioned upstream of the bristle cutting member. The blade member slides in contact with the periphery of the sleeve at a scraping position. The permanent magnet has spaced therearound at equal circumferential intervals a plurality of magnetizing positions having magnetic poles.
    Type: Grant
    Filed: August 18, 1982
    Date of Patent: August 28, 1984
    Assignee: Mita Industrial Company Limited
    Inventors: Ryutaro Yamagata, Nobuhiko Kozuka, Hitoshi Nishihama, Shigeo Koyama, Kazutada Sakai
  • Patent number: 4448519
    Abstract: An image forming apparatus is so arranged as to form an image of an original document on a photosensitive member by accommodating the plate-like photosensitive member of a rectangular or square configuration placed on an exposure section base in a housing of the image forming apparatus. The exposure section base is disengageable from the housing in a horizontal direction and has a plurality of suction holes in a region on which the photosensitive member is placed. A switch detects when the exposure section base is inserted into the housing to reach a predetermined position, and a suction device then sucks air through the suction holes.
    Type: Grant
    Filed: June 15, 1982
    Date of Patent: May 15, 1984
    Assignee: Mita Industrial Company Limited
    Inventors: Ishida, Hiroshi, Takaichi Kitagawa, Yasuji Sumida, Satoshi Nanba, Toshikazu Tomi
  • Patent number: 4440488
    Abstract: A cleaning device for an image-carrying member includes an elastic blade having a proximal end fixed to a holder and a terminal end held against the image-carrying member for removing toner from the image-carrying member upon movement of the image-carrying member. The terminal end of the blade flexes to extend forward in the direction of movement of the image-carrying member at an angle of .alpha. to a line tangential to a surface of the image carrying member rearward of a contact point between the terminal end of the blade and the image carrying member with respect to the direction of movement thereof. The blade has an axis passing through the proximal end of the blade and extending at an angle of .theta. to the tangent rearward of the contact point with respect to the direction of movement of the image-carrying member. The angles .alpha. and .theta. are selected to meet the following relationship:.theta.>90.degree.>.alpha..
    Type: Grant
    Filed: August 25, 1982
    Date of Patent: April 3, 1984
    Assignee: Mita Industrial Company Limited
    Inventors: Takashi Maekawa, Shoji Matsumoto, Toshikazu Matsui
  • Patent number: 4436412
    Abstract: A cleaning device for use on a transfer type electrostatic copying apparatus includes a magnetic brush cleaning device for cleaning off a magnetizable toner remaining on a photosensitive material after a transfer operation. A brush roller is disposed between the magnetic brush cleaning device and a transfer zone. A brush is arranged on a peripheral surface of a cylindrical sleeve of light transmitting material and is driven for rotation in contact with the photosensitive material. A charge eraser lamp is secured within the cylindrical sleeve. The charge on the photosensitive material or photoreceptor is almost completely erased, and consequently, the cleaning efficiency is markedly improved owing to the facilitated removal of the developing material by the magnetic brush.
    Type: Grant
    Filed: May 20, 1981
    Date of Patent: March 13, 1984
    Assignee: Mita Industrial Company Limited
    Inventors: Ryutaro Yamagata, Nobuhiko Kozuka, Hitoshi Nishihama, Shigeo Koyama, Kazutada Sakai
  • Patent number: 4431180
    Abstract: A roller supporting arrangement for an electrostatic copying apparatus having a plurality of pairs of copy paper transport rollers spaced along a copy paper transport passage includes a support frame for supporting the lower rollers of the respective pairs of transport rollers. A support shaft is mounted horizontally to a copying apparatus housing, by which the support frame is rotatably supported. A device is provided for pushing up the support frame and for releasing the support frame from the push-up force to be turned downward about the support shaft. Since the lower rollers of the pairs of the rollers mounted at the copy paper sheet transport passage are connected pivotally to the support frame which is rotatable about the horizontal support shaft, it is easy to open the copy paper sheet transport passage when a copy paper is jammed in the copy paper sheet transport passage.
    Type: Grant
    Filed: September 15, 1981
    Date of Patent: February 14, 1984
    Assignee: Mita Industrial Company Limited
    Inventor: Tadanobu Nakajima
  • Patent number: 4423948
    Abstract: A detecting device for detecting when the amount of toner in a dual component developing material is less than a predetermined level includes a hopper for supplying the toner, a stirring roller for stirring a carrier and the toner from the hopper, and a detector for detecting the amount of developing material provided near the stirring roller to mix the toner supplied from the hopper with the carrier. A discriminator discriminates an output signal from the detector for a predetermined interval during the rotational period of the stirring roller. An indicating element operates in response to the output signal from the discriminator to indicate when the amount of the toner in the developing material is less than the predetermined level. Since it is indicated when the toner in the developing material is less than the predetermined level, the toner is supplied according to such indication, and therefore, an undesirable deterioration of copy density is prevented.
    Type: Grant
    Filed: July 17, 1981
    Date of Patent: January 3, 1984
    Assignee: Mita Industrial Company Limited
    Inventors: Hiroshi Kimura, Masahiko Hisajima, Yutaka Shigemura, Isao Yada, Yoichiro Irie, Kiyoshi Morimoto
  • Patent number: 4415645
    Abstract: A particulate composite developer for electrophotography is disclosed, which has a novel dispersion structure comprising a continuous phase consisting of a homogeneous mixture of a resin and a pigment and a dispersed phase consisting of spherical particles of a soft parting or fixing material having an emulsion grade size and being dispersed in the continuous phase. This particulate developer has in combination improved adaptability to the developing operation, excellent transferring and cleaning properties, good ability to form a sharp image free of fog and good fixing property not causing an offset phenomenon.
    Type: Grant
    Filed: March 5, 1979
    Date of Patent: November 15, 1983
    Assignee: Mita Industrial Company Limited
    Inventors: Toshihiro Kouchi, Tatsuo Aizawa
  • Patent number: 4405226
    Abstract: The present invention relates to a developing material supplying control device for an electrostatic copying apparatus which includes an oscillator circuit composed of an oscillation coil provided along a toner supplying passage, a timer, a counter for counting the output signal from the oscillation circuit at every interval predetermined by the timer to supply a discriminating output signal when the counted value is equal to a predetermined value for each of the intervals. A toner supply acts in response to the discriminating output signal from the counter for supplying toner to the toner supplying passage. Since this invention employs the oscillation coil and does not employ a mechanical switch having a movable contact for detecting toner in the toner supplying passage, the toner supplying operation is achieved precisely.
    Type: Grant
    Filed: July 16, 1981
    Date of Patent: September 20, 1983
    Assignee: Mita Industrial Company Limited
    Inventors: Hiroshi Kimura, Masahiko Hisajima, Yutaka Shigemura, Isao Yada, Yoichiro Irie, Kiyoshi Morimoto
  • Patent number: 4400077
    Abstract: A photosensitive drum assembly for an electrostatic copying apparatus includes a cylindrical drum having a photosensitive layer provided around its outer periphery. The drum is held between a pair of flanges at opposite axial ends of the drum. Each of the flanges is formed having a diameter larger than the external diameter of the drum. At the edge of each flange, is a cylindrical portion extending along the axis of the drum to face toward the opposite flange. The end edges of the drum closely fit into the cylindrical portions. According to the present invention, since the edges of the drum closely fit into the cylindrical portions of the flanges, it is not necessary to improve the dimensional accuracy of the inside periphery of the opposite ends of the drum, while it is essential to improve the dimensional accuracy in a conventional manner.
    Type: Grant
    Filed: October 22, 1981
    Date of Patent: August 23, 1983
    Assignee: Mita Industrial Company Limited
    Inventors: Nobuhiko Kozuka, Ryutaro Yamagata, Shigeo Koyama, Hiromi Sakata, Atsushi Kano
  • Patent number: 4388396
    Abstract: A developer for electrostatic images consisting essentially of particles comprising a pigment, a binder and an offset-preventing agent selected from the group consisting of aliphatic fluorocarbon compounds and fluorochlorocarbon compounds is disclosed. When this developer is used, a high offset-preventing effect can be attained at the fixing step even if the amount incorporated of the offset-preventing agent is small, and further, the developing operation can be performed in good conditions. By incorporation of this offset-preventing agent, the flowability of particles of the developer and charge characteristics of the developer can be remarkably improved.
    Type: Grant
    Filed: April 15, 1982
    Date of Patent: June 14, 1983
    Assignee: Mita Industrial Company Limited
    Inventors: Hatsumi Nishibayashi, Yoshimi Amagai, Norio Hikake, Toshihiro Kouchi, Tatsuo Aizawa