Patents by Inventor Hiroaki Tazawa

Hiroaki Tazawa 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: 5210781
    Abstract: A rotary X-ray tube of the anode type wherein a jacket which serves to prevent lubricant from being scattered into the space in a vacuum envelope is attached to at least one of a rotary structure to which an anode target is fixed and a stationary structure for holding the rotating body, enclosing a clearance opening which forms a border relative to the space in the vacuum envelope.
    Type: Grant
    Filed: September 30, 1991
    Date of Patent: May 11, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuhiro Ono, Hidero Anno, Hiroyuki Sugiura, Takayuki Kitami, Hiroaki Tazawa
  • Patent number: 5195119
    Abstract: In a rotary-anode type X-ray tube, a rotary-anode is fixed to a cylindrical rotary structure, and a columnar stationary shaft is fitted in the rotary structure. A gap is formed between the rotary structure and the stationary shaft. The gap is filled with a liquid metal lubricant. Spiral grooves are formed in part of the outer surface of the stationary shaft to form a radial sliding bearing between the stationary shaft and the rotary structure. Spiral grooves are formed in the end faces of the stationary shaft to form a thrust sliding bearing between the stationary shaft and the rotary structure. A recess is formed in the stationary shaft to communicate with gaps in the radial sliding bearing. A lubricant storage chamber for storing the liquid metal lubricant is formed in the stationary shaft along the center axis. The storage chamber communicates with communicating holes which radially extend to be open to an outer surface region, of the stationary shaft, in which no spiral grooves are formed.
    Type: Grant
    Filed: September 27, 1991
    Date of Patent: March 16, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuhiro Ono, Hidero Anno, Hiroyuki Sugiura, Takayuki Kitami, Hiroaki Tazawa
  • Patent number: 5189688
    Abstract: A rotary-anode type X-ray tube wherein bubbles produced in the gap of a sliding bearing are securely and easily replaced with liquid metal lubricant, and the metal lubricant is prevented from leaking. The rotary anode is secured to a cylindrical rotary structure. A columnar fixed structure is secured to the rotary structure forming a gap between the rotary structure and fixed structure. A liquid metal lubricant fills the gap. Spiral grooves are formed on a part of the outer surface of the fixed structure and the sliding bearing is installed between the fixed structure and the rotary structure. The rotary structure and fixed structure are housed in a vacuum envelope. The gap of the sliding bearing is connected to the space inside the vacuum envelope through an annular space. A gap is formed between a ring block for blocking the opening of the rotary structure and the fixed structure.
    Type: Grant
    Filed: September 27, 1991
    Date of Patent: February 23, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuhiro Ono, Hidero Anno, Hiroyuki Sugiura, Takayuki Kitami, Hiroaki Tazawa
  • Patent number: 4671697
    Abstract: An apparatus for mounting an electromagnetic unit on a frame includes a mounting recess at the bottom of the main body of the electromagnetic unit, a guide recess which is communicated with the mounting recess at one side thereof so that it is normal to the mounting recess, and a slidable member which is slidably inserted into the guide recess and normally biased toward the mounting recess by means of a spring supported by a projection disposed in the guide recess, the improvement comprising a stopper disposed in a hole formed in the slidable member, which opposes the spring bearing in the guide recess. The stopper in the hole also serves as a spring guide.
    Type: Grant
    Filed: May 7, 1985
    Date of Patent: June 9, 1987
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Isao Ando, Hiroaki Tazawa, Yuji Sako, Shigeharu Ootsuka, Yuji Mizuno, Kosaku Ikeda
  • Patent number: 4642429
    Abstract: A switch characterized by a stationary contact element joined to a stationary contact, a movable contact element joined to a movable contact in a facing relationship to said stationary contact element, a first metallic arc extinguishing plate formed of a U-shaped vertical wall and disposed with its open end facing toward a tip of said stationary contact and which surround said stationary contact element, and a second metallic arc extinguishing plate disposed in parallel to and at the remote side from said contact elements of said first metallic arc extinguishing plate, said first metallic arc extinguishing plates being disposed at predetermined gaps relative to said stationary contact.
    Type: Grant
    Filed: July 2, 1984
    Date of Patent: February 10, 1987
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Teijiro Mori, Yuichi Wada, Yuji Sako, Hiroaki Tazawa, Hiroyuki Okado
  • Patent number: 4539451
    Abstract: A switch for making and breaking an electric current and having an arc-extinguishing mechanism. Said switch includes a fixed contact plate having a fixed contact thereon, a movable contact plate having a fixed contact adapted for movement to come into and go out of said fixed contact and an arc deflecting plate provided substantially parallel to said movement. Said arc deflecting plate is made of magnetic metal and is formed with a U-shaped portion in proximity to said fixed contact plate.
    Type: Grant
    Filed: November 10, 1983
    Date of Patent: September 3, 1985
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Teijiro Mori, Yuichi Wada, Shizutaka Nishisako, Hiroaki Tazawa, Shigeru Masuda
  • Patent number: 4450328
    Abstract: An electromagnetic contact having a fixed and a moveable contact which are brought into and out of disengagement by operation of an electromagnet. An arc runner substantially surrounding the contacts aide in extinguishing the arc created upon separation of the contacts. The overhanging plate of the arc runner has stoppers which engage the side plates thereby preventing the overhanging plate from bending inward and decreasing the effectiveness of the arc runner. The arc runner is also provided with lead parts to separate the arc and purge holes for passing the hot gasses generated.
    Type: Grant
    Filed: September 14, 1981
    Date of Patent: May 22, 1984
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shizutaka Nishizako, Hiroaki Tazawa