Patents by Inventor Hisashi Tomiyama

Hisashi Tomiyama 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).

  • Lighting control circuit, illuminating lamp using the lighting control circuit, and lighting device using the illuminating lamp
    Patent number: 9743470
    Abstract: A lighting control circuit for an illuminating lamp includes: a rectifier part that is connected to a ballast to which commercial alternating-current electric power is supplied, and converts the alternating current to direct current; a smoothing capacitor that is provided on an output side of the rectifier part, and removes an alternating-current component included in direct current outputted from the output side; a drive circuit that has a switching element, and performs on-off control on electric current flowing to a plurality of solid-state light-emitting elements connected in series to both ends of the smoothing capacitor; and an inductor that is provided in an electric power supply system between the ballast and the smoothing capacitor.
    Type: Grant
    Filed: April 15, 2016
    Date of Patent: August 22, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hisashi Tomiyama, Masaharu Urano, Kazuaki Iseda, Shigemi Hagiwara
  • LIGHTING CONTROL CIRCUIT, ILLUMINATING LAMP USING THE LIGHTING CONTROL CIRCUIT, AND LIGHTING DEVICE USING THE ILLUMINATING LAMP
    Publication number: 20160234896
    Abstract: A lighting control circuit for an illuminating lamp includes: a rectifier part that is connected to a ballast to which commercial alternating-current electric power is supplied, and converts the alternating current to direct current; a smoothing capacitor that is provided on an output side of the rectifier part, and removes an alternating-current component included in direct current outputted from the output side; a drive circuit that has a switching element, and performs on-off control on electric current flowing to a plurality of solid-state light-emitting elements connected in series to both ends of the smoothing capacitor; and an inductor that is provided in an electric power supply system between the ballast and the smoothing capacitor.
    Type: Application
    Filed: April 15, 2016
    Publication date: August 11, 2016
    Inventors: Hisashi TOMIYAMA, Masaharu URANO, Kazuaki ISEDA, Shigemi HAGIWARA
  • Lighting control circuit, illuminating lamp using the lighting control circuit, and lighting device using the illuminating lamp
    Patent number: 9357599
    Abstract: A lighting control circuit for an illuminating lamp includes: a rectifier part that is connected to a ballast to which commercial alternating-current electric power is supplied, and converts the alternating current to direct current; a smoothing capacitor that is provided on an output side of the rectifier part, and removes an alternating-current component included in direct current outputted from the output side; a drive circuit that has a switching element, and performs on-off control on electric current flowing to a plurality of solid-state light-emitting elements connected in series to both ends of the smoothing capacitor; and an inductor that is provided in an electric power supply system between the ballast and the smoothing capacitor.
    Type: Grant
    Filed: June 27, 2012
    Date of Patent: May 31, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hisashi Tomiyama, Masaharu Urano, Kazuaki Iseda, Shigemi Hagiwara
  • LIGHTING CONTROL CIRCUIT, ILLUMINATING LAMP USING THE LIGHTING CONTROL CIRCUIT, AND LIGHTING DEVICE USING THE ILLUMINATING LAMP
    Publication number: 20140152184
    Abstract: A lighting control circuit for an illuminating lamp includes: a rectifier part that is connected to a ballast to which commercial alternating-current electric power is supplied, and converts the alternating current to direct current; a smoothing capacitor that is provided on an output side of the rectifier part, and removes an alternating-current component included in direct current outputted from the output side; a drive circuit that has a switching element, and performs on-off control on electric current flowing to a plurality of solid-state light-emitting elements connected in series to both ends of the smoothing capacitor; and an inductor that is provided in an electric power supply system between the ballast and the smoothing capacitor.
    Type: Application
    Filed: June 27, 2012
    Publication date: June 5, 2014
    Inventors: Hisashi Tomiyama, Masaharu Urano, Kazuaki Iseda, Shigemi Hagiwara