Patents by Inventor Shoouji Nakajima

Shoouji Nakajima 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).

  • Loudspeaker
    Patent number: 7123738
    Abstract: The present invention is directed to a speaker using lightweight, highly rigid diaphragm having excellent frequency characteristic and improving resistance to environment (including resistance to UV and resistance to fading). For this end, the speaker utilizes a cone-shaped diaphragm made from foamed or cellular resin such as polyethylene terephthalate (PET) resin or polyethylene naphthalate (PEN) resin with 30 ?m average cell size. The use of such cone-shaped diaphragm is effective to improve sound quality of the speaker.
    Type: Grant
    Filed: October 3, 2000
    Date of Patent: October 17, 2006
    Assignees: Matsushita Electric Industrial Co., Ltd., The Furukawa Electric Co., Ltd.
    Inventors: Shinya Mizone, Keiji Ishikawa, Shoouji Nakajima, Akira Kabumoto, Satoshi Ono