Patents Assigned to Tokyo Metropolitan
  • Densitometer using a microwave
    Patent number: 5502393
    Abstract: A densitometer using a microwave comprises a microwave detection section, a phase detection section, and a density calculation section. The microwave detection section picks up a first microwave receiving signal by transmitting and receiving a microwave of a frequency band of 1.4 --GHz-- to 1.75 --GHz-- to/from a reference fluid, and a second microwave receiving signal by transmitting and receiving a microwave of a frequency band of 1.4 --GHz-- to 1.75 --GHz-- to/from a measuring fluid. The phase detection section obtains a phase difference between the first microwave receiving signal and the second microwave receiving signal. The density calculation section calculates the density of measuring fluid based on the phase difference obtained by the phase detection section.
    Type: Grant
    Filed: March 30, 1994
    Date of Patent: March 26, 1996
    Assignees: Kabushiki Kaisha Toshiba, Tokyo Metropolitan
    Inventors: Seiji Yamaguchi, Takeshi Yamaura, Takatsugu Ogata, Tsutomu Suzuki, Ikuo Arai
  • Method and apparatus for controlling sludge dewatering
    Patent number: 5382356
    Abstract: The feature of the present invention resides in that when a polyelectrolyte coagulant is added to sludge to dewater the sludge in a sewage treatment plant, the dosage level of the polyelectrolyte coagulant to be to the sludge is controlled most properly, whereby moisture content of dewatered cake can be minimized.
    Type: Grant
    Filed: June 10, 1992
    Date of Patent: January 17, 1995
    Assignees: Tokyo Metropolitan, Tokyo Metropolitan Sewerage Service Corp., Japan Organo Co., Ltd.
    Inventors: Makoto Thogho, Tamotsu Hattori, Noboru Okazaki, Kozaburo Akamatus, Tomoyuki Hayashi, Tomohiko Kusumi