Patents by Inventor Freddy Eddy Van Den Worm

Freddy Eddy Van Den Worm 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).

  • Microphone having an electrostatic cartridge having a structural electrical resistor
    Patent number: 3991285
    Abstract: Microphone including an electrostatic microphone cartridge at least one of the electrodes of which is connected to a large resistor which forms part of an electronic circuit. The circuit may be the supply part or the input of the associated microphone amplifier which generally is incorporated in the cartridge. The large resistor is constituted by a structural component of the cartridge, which component is made of a weakly conductive synthetic material. The conductive synthetic material may be a conductive silicone rubber or a conductive polypropylene.
    Type: Grant
    Filed: September 23, 1974
    Date of Patent: November 9, 1976
    Assignee: U.S. Philips Corporation
    Inventors: Freddy Eddy Van Den Worm, Petrus Antonius Swarte