Patents by Inventor Naoki Ohta

Naoki Ohta 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: 6218548
    Abstract: A compound represented by formula (III): wherein n is an integer of 2 to 5; and R11 represents a substituent group represented by formula: wherein Ra, Rb and Rc each represents a phenyl, phenylmethyl or naphthyl group (which may be substituted with at least one substituent group selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms, a halogen atom and a nitro group), a hydrogen atom, or an alkyl group having 1 to 4 carbon atoms, with the proviso that Ra, Rb and Rc are different from one another, and a salt thereof.
    Type: Grant
    Filed: November 23, 1999
    Date of Patent: April 17, 2001
    Assignee: Daiichi Paharmaceutical Co., Ltd.
    Inventors: Toshifumi Akiba, Tutomu Ebata, Tatsuru Saito, Sadahiro Shimizu, Keiichi Hirai, Naoki Ohta, Toshiaki Tojo
  • Patent number: 6098988
    Abstract: A mechanism for forming a liquid-tight seal around the rotary shaft of a liquid pump having a stationary ring attached to the casing of the pump and a rotating ring attached to the rotary shaft and contacting the stationary ring. The stationary ring is formed from baked carbon, while the rotating ring is a sintered product of silicon nitride. The stationary ring has an effective seal width ratio, rp/Di, of 0.07/1 to 0.22/1, where rp is the width of the effective seal surface of the stationary ring and Di is its inside diameter.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: August 8, 2000
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Yasunobu Kawakami, Naoki Ohta, Hiroshi Ichikawa, Masaru Kanno, Katsuharu Kinoshita, Masayasu Sakata
  • Patent number: 6013806
    Abstract: This invention is to provide a compound represented by the following formula (I) and a compound represented by the following formula (II) useful as an antibacterial agent which is obtained by the compound of formula (I), and also to provide a novel synthetic process for the inexpensive, short-step and industrially advantageous production thereof.
    Type: Grant
    Filed: July 9, 1998
    Date of Patent: January 11, 2000
    Assignee: Daiichi Pharmaceutical Co., Ltd.
    Inventors: Toshifumi Akiba, Tutomu Ebata, Tatsuru Saito, Sadahiro Shimizu, Keiichi Hirai, Naoki Ohta, Toshiaki Tojo
  • Patent number: 5856518
    Abstract: This invention is to provide a compound represented by the following formula (I) and a compound represented by the following formula (II) useful as an antibacterial agent which is obtained by the compound of folmula (I), and also to provide a novel synthetic process for the inexpensive, short-step and industrially advantageous production thereof.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: January 5, 1999
    Assignee: Daiichi Pharmaceutical Co., Ltd.
    Inventors: Toshifumi Akiba, Tutomu Ebata, Tatsuru Saito, Sadahiro Shimizu, Keiichi Hirai, Naoki Ohta, Toshiaki Tojo
  • Patent number: 5851719
    Abstract: A developing sleeve for electrophotography is disclosed which has a coating film comprising electroconductive and preferably lubricating particles dispersed in an acrylic resin in which the content of components having a molecular weight lower than 500 is not higher than 3% by weight. The developing sleeve is effective in preventing development ghosts while preventing toner dusting during transfer from becoming worse and has a small environmental dependence of developing properties.
    Type: Grant
    Filed: December 16, 1996
    Date of Patent: December 22, 1998
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Masayuki Takei, Yuichi Yashiki, Hideyuki Akagi, Naoki Ohta, Yasushi Sakata, Junichi Tomonaga
  • Patent number: 5767461
    Abstract: An elevator group supervisory control system for selecting the most suitable car among a plurality of elevators, when a hall call is made, to assign to the hall call, comprising: temporary assigning means for temporarily assigning the car by a conventional method such as a fuzzy group supervisory control based on group data representing states of the elevator system at the moment when a new hall call is made; and a neural net for receiving numerical values converted from group data including the result of judgment of the temporary assigning means and outputting an assignment fitness of each elevator. It decides the most suitable elevator from the output pattern of the neural net to assign to the hall call.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: June 16, 1998
    Assignee: Fujitec Co., Ltd.
    Inventors: Masami Nakagawa, Kenji Sasaki, Sandor Markon, Ichiro Nagashima, Takeshi Midoritani, Tomoaki Tanabe, Naoki Ohta
  • Patent number: 5554009
    Abstract: A swash-plate hydraulic pressure device for use as a hydraulic pump or motor includes a cylinder block having an annular array of cylinder holes defined therein around an axis. A plurality of plungers of a ceramic material are reciprocally movably disposed in the cylinder holes, respectively, the plungers having respective partly spherical tip ends. A swash plate of metal is disposed around the cylinder block for rotation with respect to the cylinder block, the swash plate having a annular groove of a partly spherical cross section defined therein and, the partly spherical tip ends of the plungers engaging in the groove. The tip ends of the plungers preferably have a pore area percentage of at most 7.8% and a maximum surface roughness of at most 1.6 s. The partly spherical tip end of each of the plungers has a radius R.sub.0 of curvature, each of the plungers has a diameter D, the groove has a radius R.sub.1 of curvature and a depth E. The ratios R.sub.0 /D, R.sub.0 /R.sub.1, and E/R.sub.
    Type: Grant
    Filed: October 11, 1994
    Date of Patent: September 10, 1996
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Naoki Ohta, Naoki Kamide, Jun Iwamoto, Yasunobu Kawakami, Tsutomu Hayashi