Patents by Inventor David Choit

David Choit 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).

  • Multi function magnetic decoupler
    Patent number: 8305177
    Abstract: A magnet assembly for decoupling a plurality of different types of magnetically operated security devices includes a center pole magnet having a magnetic orientation along a first direction. A plurality of magnets adjacent to and surrounding the center pole magnet define an opening above the center pole magnet. Each adjacent magnet has a magnetic orientation orthogonal to the first direction. An end pole magnet is disposed adjacent to one of the magnets adjacent to the center pole magnet. The end pole magnet has magnetic orientation opposed to the first direction.
    Type: Grant
    Filed: January 5, 2010
    Date of Patent: November 6, 2012
    Assignee: Dexter Magnetic Technologies, Inc.
    Inventors: Chun Li, David Choit
  • MULTI FUNCTION MAGNETIC DECOUPLER
    Publication number: 20100176903
    Abstract: A magnet assembly for decoupling a plurality of different types of magnetically operated security devices includes a center pole magnet having a magnetic orientation along a first direction. A plurality of magnets adjacent to and surrounding the center pole magnet define an opening above the center pole magnet. Each adjacent magnet has a magnetic orientation orthogonal to the first direction. An end pole magnet is disposed adjacent to one of the magnets adjacent to the center pole magnet. The end pole magnet has magnetic orientation opposed to the first direction.
    Type: Application
    Filed: January 5, 2010
    Publication date: July 15, 2010
    Inventors: Chun Li, David Choit
  • Magnetic decoupler
    Patent number: 6084498
    Abstract: An improved magnetic decoupler with a magnetic field shape, strength and gradient optimized for releasing security tags, such as an antitheft device of the type described above. Due to the structure of the magnetic decoupler, it contains less ferrous material than prior art decouplers heretofore employed. Reduction in size of the magnetic decoupler, along with improved magnetic strength, derive from the magnet assembly including magnets arranged with orientations that increase axial magnetic field gradient by superposition of the magnetic fields of each magnet.
    Type: Grant
    Filed: April 7, 1999
    Date of Patent: July 4, 2000
    Assignee: Dexter Magnetic Technologies, Inc.
    Inventors: Richard E. Stelter, David Choit, Thomas J. Devaney
  • Magnetic decoupler
    Patent number: 5959520
    Abstract: An improved magnetic decoupler with a magnetic field shape, strength and gradient optimized for releasing security tags, such as an antitheft device of the type described above. Due to the structure of the magnetic decoupler, it contains less ferrous material than prior art decouplers heretofore employed. Reduction in size of the magnetic decoupler, along with improved magnetic strength, derive from the magnet assembly including magnets arranged with orientations in quadrature to increase axial magnetic field gradient within the decoupler cavity by superposition of the magnetic fields of each magnet.
    Type: Grant
    Filed: August 21, 1998
    Date of Patent: September 28, 1999
    Assignee: Dexter Magnetic Technologies, Inc.
    Inventors: Richard E. Stelter, David Choit, Thomas J. Devaney