Patents by Inventor Carl Van Gelder

Carl Van Gelder 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: 5151943
    Abstract: The present invention features a dynamic speaker having improved output power and decreased second harmonic distortion. The reduction in second harmonic distortion results from a sandwich-type shielding arranged about the stepped pole piece of the speaker. The shielding protects the voice coil from a non-symmetrical magnetic flux interaction with the air gap between the pole piece and the front plate. This reduces the second harmonic distortion due to the non-symmetry of the minor hysteresis loop formed by the magnetic field of the energized voice coil with the static magnetic field acting on the ferromagnetic material making up the pole piece. Additionally, the decrease in inductance due to the location of the nonferromagnetic shielding members produces an increase in output.
    Type: Grant
    Filed: November 13, 1990
    Date of Patent: September 29, 1992
    Assignee: McIntosh Laboratory, Inc.
    Inventor: Carl Van Gelder