Patents by Inventor Tadasi Itagaki

Tadasi Itagaki 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).

  • Piezoelectric transducer with multiple electrode areas
    Patent number: 4170742
    Abstract: An electro-acoustic transducer comprising a flexible film of piezoelectric material, at least one electrode provided on one side of said film amd a plurality of electrodes provided on the other side of said film to form a piezoelectric diaphragm and said piezoelectric diaphragm is imparted with a locally differing resiliency and/or tension, is provided. By using this piezoelectric electro-acoustic transducer in a loudspeaker, it is possible to improve acoustic characteristics thereof particularly in a high frequency range, to obtain a variety of acoustic characteristics and to effect motional feed back to minimize distortion of reproduced sound without involving any difficulty in manufacturing or affecting proper performance of the transducer.
    Type: Grant
    Filed: August 5, 1977
    Date of Patent: October 9, 1979
    Assignees: Pioneer Electronic Corporation, Tokorozawa Electronic Corporation
    Inventors: Tadasi Itagaki, Kiyonori Iwama, Toshikazu Yoshimi
  • Piezoelectric electro-acoustic transducer
    Patent number: 4045695
    Abstract: An electro-acoustic transducer comprising a flexible film of piezoelectric material, at least one electrode provided on one side of said film and a plurality of electrodes provided on the other side of said film to form a piezoelectric diaphragm and said piezoelectric diaphragm is imparted with a locally differing resiliency and/or tension, is provided. By using this piezoelectric electro-acoustic transducer in a loudspeaker, it is possible to improve acoustic characteristics thereof particularly in a high frequency range, to obtain a variety of acoustic characteristics and to effect motional feed back to minimize distortion of reproduced sound without involving any difficulty in manufacturing or affecting proper performance of the transducer.
    Type: Grant
    Filed: July 14, 1975
    Date of Patent: August 30, 1977
    Assignees: Pioneer Electronic Corporation, Tokorozawa Electronic Corporation
    Inventors: Tadasi Itagaki, Kiyonori Iwama, Toshikazu Yoshimi
  • Loud speaker with stable damping
    Patent number: 4030564
    Abstract: A loud speaker having air communicating holes within the rear portion of the frame and facing the diaphragm is provided with regularly woven wire gauze formed of warp and weft wire threads of different diameter, which gauze covers the communicating holes to obtain a stable vibration damping effect.
    Type: Grant
    Filed: October 30, 1975
    Date of Patent: June 21, 1977
    Assignees: Pioneer Electronic Corporation, Tokorozawa Electronic Corporation
    Inventor: Tadasi Itagaki