Patents by Inventor Wiert Kopinga

Wiert Kopinga 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).

  • Magnet system for an electroacoustic transducer
    Patent number: 4527017
    Abstract: An electroacoustic transducer comprising a diaphragm provided with conductors and a magnet system having permanent magnetic zones at both sides of the diaphragm for producing an energizing field at the location of the conductors. At the boundary areas of the magnetic zones auxiliary magnetic fields are produced in order to reduce stray fields at the location of the boundary areas. This results in a better concentration of the energizing magnetic fields in the plane of the diaphragm so that a stronger magnetic field is obtained at the location of the conductors.
    Type: Grant
    Filed: October 27, 1980
    Date of Patent: July 2, 1985
    Assignee: U.S. Philips Corporation
    Inventors: Wiert Kopinga, Herbert Mimmel
  • Mechanical filter for an electrodynamic transducer
    Patent number: 4379952
    Abstract: An electrodynamic transducer having a mechanical filter as a coupling element between a voice coil former (3) and cone (1) in order to obtain a frequency characteristic whose high frequency roll-off begins at a lower frequency, in which a part (7) of the centering diaphragm (4) situated within the periphery of the voice coil former is used as the mechanical filter.
    Type: Grant
    Filed: November 24, 1980
    Date of Patent: April 12, 1983
    Assignee: U.S. Philips Corporation
    Inventors: Adrianus J. M. Kaizer, Wiert Kopinga