Patents by Inventor Tomoyuki YOKOGAWA

Tomoyuki YOKOGAWA 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: 11915951
    Abstract: A plasma processing apparatus includes a stage disposed in a processing chamber for mounting a wafer, a plasma generation chamber disposed above the processing chamber for plasma generation using process gas, a plate member having multiple introduction holes, made of a dielectric material, disposed above the stage and between the processing chamber and the plasma generation chamber, and a lamp disposed around the plate member for heating the wafer. The plasma processing apparatus further includes an external IR light source, an emission fiber arranged in the stage, that outputs IR light from the external IR light source toward a wafer bottom, and a light collection fiber for collecting IR light from the wafer. Data obtained using only IR light from the lamp is subtracted from data obtained also using IR light from the external IR light source during heating of the wafer. Thus, a wafer temperature is determined.
    Type: Grant
    Filed: June 26, 2020
    Date of Patent: February 27, 2024
    Assignee: HITACHI HIGH-TECH CORPORATION
    Inventors: Hiroyuki Kobayashi, Nobuya Miyoshi, Kazunori Shinoda, Tatehito Usui, Naoyuki Kofuji, Yutaka Kouzuma, Tomoyuki Watanabe, Kenetsu Yokogawa, Satoshi Sakai, Masaru Izawa
  • Publication number: 20200212711
    Abstract: A power distribution system includes: a distribution unit that splits a supply AC current Ip from an external AC power supply 2 into a first distributed AC current and a second distributed AC current and distributes the first distributed AC current to a first load; a current monitoring unit that monitors the supply AC current Ip; a bidirectional AC-DC converter that converts, when operated as an AC-DC converter, the second distributed AC current distributed from the distribution unit into a supply DC current and supplies the supply DC current to a second load 5 and that converts, when operated as a DC-AC inverter, a regenerative DC current from the second load into a regenerative AC current and supplies the regenerative AC current to the first load; and a control unit that controls the bidirectional AC-DC converter based on the supply AC current Ip monitored by the monitoring unit.
    Type: Application
    Filed: December 23, 2019
    Publication date: July 2, 2020
    Inventors: Takashi OGAWA, Tomoaki SAWACHIKA, Tomoyuki YOKOGAWA
  • Patent number: 8558501
    Abstract: The command signal processing unit outputs, when a first PWM frequency command signal is received, a high-PWM frequency command signal such that an asynchronous PWM control is performed at a PWM frequency of a predetermined constant frequency. The command signal processing unit outputs, when a second PWM frequency command signal is received, a low-PWM frequency command signal such that an asynchronous or synchronous PWM control is performed at a frequency lower than the above-described frequency. The PWM frequency control unit controls the PWM frequency such that an asynchronous PWM control is performed if a motor has a rotational speed less than a predetermined rotational speed and that a synchronous PWM control is performed if the motor has a rotational speed greater than or equal to the predetermined rotational speed, when a low-PWM frequency command signal is input.
    Type: Grant
    Filed: January 5, 2012
    Date of Patent: October 15, 2013
    Assignee: Nabtesco Corporation
    Inventors: Tokuji Tsunematsu, Kazushige Nakajima, Hiroyuki Kitazwa, Tomoyuki Yokogawa
  • Publication number: 20120187892
    Abstract: The command signal processing unit outputs, when a first PWM frequency command signal is received, a high-PWM frequency command signal such that an asynchronous PWM control is performed at a PWM frequency of a predetermined constant frequency. The command signal processing unit outputs, when a second PWM frequency command signal is received, a low-PWM frequency command signal such that an asynchronous or synchronous PWM control is performed at a frequency lower than the above-described frequency. The PWM frequency control unit controls the PWM frequency such that an asynchronous PWM control is performed if a motor has a rotational speed less than a predetermined rotational speed and that a synchronous PWM control is performed if the motor has a rotational speed greater than or equal to the predetermined rotational speed, when a low-PWM frequency command signal is input.
    Type: Application
    Filed: January 5, 2012
    Publication date: July 26, 2012
    Applicant: NABTESCO CORPORATION
    Inventors: Tokuji TSUNEMATSU, Kazushige NAKAJIMA, Hiroyuki KITAZWA, Tomoyuki YOKOGAWA