Patents by Inventor Toshimi Furukawa

Toshimi Furukawa 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: 5539833
    Abstract: An audio signal amplifier device is disclosed, and includes two parallel compass controller circuits (6, 7), each of the circuits (6, 7) having the identical configuration and including a low compass controlling circuit (1, 8) having a plurality of transformers T.sub.1, T.sub.2 connected in series, a medium compass controlling circuit (2, 9) having a capacitor C.sub.2 and a resistor R.sub.3 connected in series, and a high compass controlling circuit (3, 10) having a capacitor C.sub.3 and an amplifier A.sub.2 connected in series, those three compass controlling circuits being coupled in parallel.The parallel compass controller circuits (6, 7) are connected in series through a pre-amplifier PA.sub.1, wherein the post-stage circuit (7) is coupled with an output transformer T.sub.4 through a pre-amplifier PA.sub.3, and the pre-stage circuit (6) is coupled with an input transformer T.sub.3 through a pre-amplifier PA.sub.2.
    Type: Grant
    Filed: October 24, 1994
    Date of Patent: July 23, 1996
    Inventors: Osamu Yamashita, Toshimi Furukawa