Patents by Inventor Tetsuaki Imamura

Tetsuaki Imamura 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: 4253083
    Abstract: A traffic signal system for blind people which can be combined with an existing traffic signal device the device having a sound signal generator electrically connected to a blue light of the pedestrian traffic signal device for generating a signal representative of imitation sound synchronous with lighting of said blue light, a noise detector, a volume controller for controlling the output of the signal generator in accordance with the detected noise signal of the noise detector, a control gate for preventing the noise signal of said noise detector from being supplied to the volume controller when the generator is on, and a speaker for emitting imitation sound having a volume corresponding to the level of the surrounding noise.
    Type: Grant
    Filed: March 15, 1978
    Date of Patent: February 24, 1981
    Assignee: Masayuki Hattori
    Inventor: Tetsuaki Imamura