Patents by Inventor Hideki Uemura

Hideki Uemura 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: 4839915
    Abstract: In an inverter type X-ray apparatus comprising an inverter including a plurality of switching elements operated alternately to generate an AC voltage having a rectangular waveform, a high voltage transformer transforming the AC voltage of rectangular waveform into a high AC voltage, a high voltage rectifier circuit rectifying the high AC voltage into a DC voltage, and an X-ray tube to which the DC voltage is applied as a tube voltage, the switching elements are driven to make chopping operation at a frequency high than the inverter drive frequency, and a pattern signal is generated for gradually increasing the duty cycle of the chopping operation in synchronism with the timing of switching over the switching elements.
    Type: Grant
    Filed: January 15, 1988
    Date of Patent: June 13, 1989
    Assignee: Hitachi Medical Corp.
    Inventors: Kazuo Kaneko, Takanobu Hatakeyama, Hirofumi Hino, Hideki Uemura, Kazuo Yamamoto
  • Patent number: 4794505
    Abstract: A power supply system including a DC-to-AC inverter stage and a voltage step-up transformer is intended to have the output voltage settlement with a minimal delay and suppressed bounce at the start-up of power supply to the load, and also intended to reduce the load voltage bounce caused by the leakage inductance and stray capacitance of a high tension step-up transformer.
    Type: Grant
    Filed: November 19, 1987
    Date of Patent: December 27, 1988
    Assignee: Hitachi Medical Corporation
    Inventors: Hirofumi Hino, Hideki Uemura, Kazuo Kaneko
  • Patent number: 4742535
    Abstract: Disclosed is an inverter type X-ray apparatus comprising a DC-DC converter for converting a DC voltage into a different DC voltage, an inverter for inverting an output voltage of the DC-DC converter into an AC voltage, a high voltage transformer for transforming an output voltage of the inverter into a higher voltage, a rectifier for converting an AC output voltage of the transformer into a DC voltage, and an X-ray tube to which an output voltage of the rectifier is applied. In the apparatus, the DC-DC converter includes a reactor, a switching element and a capacitor which are interconnected so that the DC-DC converter can generate an output voltage higher or lower than an input voltage.
    Type: Grant
    Filed: December 23, 1985
    Date of Patent: May 3, 1988
    Assignee: Hitachi Medical Corporation
    Inventors: Hirofumi Hino, Hideki Uemura, Kazuo Kaneko, Takanobu Hatakeyama, Kazuo Yamamoto