Patents by Inventor Takeshi Usuda

Takeshi Usuda 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: 9240719
    Abstract: A control circuit (24) includes a calculation means (28) which determines ON time and OFF time of a main switching element (14) and a drive pulse generating means (30) which generates drive pulses that turn the main switching element (14) ON and OFF. A control function formula which prescribes a relationship between an output voltage (Vo) and an output differential value (Vd) by a negative linear function and the like is defined in the calculation means (28). The calculation means (28) samples an input voltage signal (Vi) and an output voltage signal (Vo) at a timing synchronized with a switching cycle of the main switching element (14), and calculates the ON time and OFF time of the main switching element (14) thereafter so as to satisfy the control function formula. The drive pulse generating means (30) generates drive pulses (V14) which turn the main switching element (14) ON and OFF on the basis of the ON and OFF time determined by the calculation means (28).
    Type: Grant
    Filed: July 25, 2012
    Date of Patent: January 19, 2016
    Assignee: COSEL CO. LTD.
    Inventors: Takeshi Usuda, Yoshiki Matsuo
  • Publication number: 20140159694
    Abstract: A control circuit (24) includes a calculation means (28) which determines ON time and OFF time of a main switching element (14) and a drive pulse generating means (30) which generates drive pulses that turn the main switching element (14) ON and OFF. A control function formula which prescribes a relationship between an output voltage (Vo) and an output differential value (Vd) by a negative linear function and the like is defined in the calculation means (28). The calculation means (28) samples an input voltage signal (Vi) and an output voltage signal (Vo) at a timing synchronized with a switching cycle of the main switching element (14), and calculates the ON time and OFF time of the main switching element (14) thereafter so as to satisfy the control function formula. The drive pulse generating means (30) generates drive pulses (V14) which turn the main switching element (14) ON and OFF on the basis of the ON and OFF time determined by the calculation means (28).
    Type: Application
    Filed: July 25, 2012
    Publication date: June 12, 2014
    Applicant: COSEL CO. LTD.
    Inventors: Takeshi Usuda, Yoshiki Matsuo
  • Patent number: 8400120
    Abstract: A control function formula which provides a relationship between an output voltage signal Vo and an output differential value with, for example, a negative linear function is defined in a calculation means. The calculation means samples an input voltage signal, an output voltage signal and an output differential signal at time instants in synchronization with a cycle of switching of a main switching element, and calculates subsequent ON and OFF durations of the main switching elements such that the control function formula might be satisfied. A drive pulse generation means generates a drive pulse with which the main switching element is turned on and off based on the ON and OFF durations determined by the calculation means. The output differential signal is generated by, for example, a capacitor current detection means or an observer device which detect a current of a smoothing capacitor.
    Type: Grant
    Filed: October 25, 2010
    Date of Patent: March 19, 2013
    Assignee: Cosel Co., Ltd.
    Inventors: Takeshi Usuda, Yoshiki Matsuo, Takeshi Takayanagi, Yasuhiro Masuya
  • Publication number: 20110096571
    Abstract: A control function formula which provides a relationship between an output voltage signal Vo and an output differential value with, for example, a negative linear function is defined in a calculation means. The calculation means samples an input voltage signal, an output voltage signal and an output differential signal at time instants in synchronization with a cycle of switching of a main switching element, and calculates subsequent ON and OFF durations of the main switching elements such that the control function formula might be satisfied. A drive pulse generation means generates a drive pulse with which the main switching element is turned on and off based on the ON and OFF durations determined by the calculation means. The output differential signal is generated by, for example, a capacitor current detection means or an observer device which detect a current of a smoothing capacitor.
    Type: Application
    Filed: October 25, 2010
    Publication date: April 28, 2011
    Applicant: Cosel Co., Ltd.
    Inventors: Takeshi USUDA, Yoshiki Matsuo, Takeshi Takayanagi, Yasuhiro Masuya