Patents by Inventor Lydia Isfan

Lydia Isfan 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 with a heat resistant two-part diaphragm
    Patent number: 4320264
    Abstract: A loudspeaker is disclosed in which the frustoconical diaphragm is formed in two parts, including a first or outer part made of synthetic material e.g. polypropylene or polystyrene, and a second or inner part of paper or plastic material having higher heat resistance than the first part. The second part is therefore able to withstand the high temperatures of the moving coil support to which it is attached while affording advantages of synthetic material diaphragms.
    Type: Grant
    Filed: June 5, 1980
    Date of Patent: March 16, 1982
    Assignee: Siare-Societe Industrielle d'Applications/Radio-Electriques
    Inventors: Michel Visan, Lydia Isfan