Patents by Inventor David Todd Gray

David Todd Gray 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: 10175200
    Abstract: Methods of detecting non-uniformities in a material are described. Such methods can comprise inducing changes in strain state or changing the magnetic moment of a material and measuring magnetic flux leakage that is synchronous with the changes in strain state or magnetic moment, while simultaneously applying an external magnetic field to control the relative magnitude of the magnetic flux leakage.
    Type: Grant
    Filed: May 21, 2015
    Date of Patent: January 8, 2019
    Assignee: Prime Photonics, LC
    Inventors: Clark Davis Boyd, David Todd Gray, Jonathan Drapala Sides
  • Patent number: 9793829
    Abstract: Provided is a magneto-thermoelectric generator (MTG) device for energy harvesting and more particularly a device for converting waste thermal heat from a photovoltaic cell into mechanical energy and ultimately into electrical energy. Embodiments operate on the principle of thermally-induced switching between open and closed states of a ferromagnetic switch to generate mechanical oscillations that cause strain in a piezoelectric material, resulting in the generation of electrical energy. A structure capable of providing a non-linear restoring force provides mechanical energy to the device, which is a significant improvement over prior art MTG devices employing a linear spring restorative force. The device is also provided as a hybrid photovoltaic (PV)/MTG energy harvester for scavenging heat from photovoltaic cells. The hybrid PV/MTG device is particularly useful for harvesting waste heat to boost power generation, extend flight duration, and provide thermal management aboard HALE platforms.
    Type: Grant
    Filed: September 16, 2014
    Date of Patent: October 17, 2017
    Assignee: Prime Photonics, LC
    Inventors: David Todd Gray, John Moore Coggin
  • Publication number: 20160333167
    Abstract: Polymer matrix composites normally consist of spherical or ellipsoidal reinforcement phases distributed randomly throughout the material. The spherical shape of the reinforcing materials reduces the effective electromagnetic properties of the reinforcement. Provided is a composite material which advantageously uses anisotropic electromagnetic properties of high aspect ratio loading using alignment to optimize the extrinsic effective electromagnetic property of the composite. Methods of manufacturing the composite are also described.
    Type: Application
    Filed: May 16, 2016
    Publication date: November 17, 2016
    Inventors: David Todd Gray, David Berry
  • Patent number: 9470437
    Abstract: Magnetothermal pump devices are provided. Such devices can operate on the principle of thermally induced switching between open and closed states of a magnetic switch to generate mechanical oscillations. Exemplary devices provided include a thermal gradient and a magnet with a Curie temperature at or within this gradient. When the soft magnet is below the Curie temperature, it has sufficient magnetic force to bind a hard magnet at the hot side of the gradient. Heating of the magnet at the hot side causes it to exceed its Curie temperature, resulting in loss of magnetic attraction. At this stage, a restorative force exceeds the magnetic force, causing the magnet to shift to the cold side of the gradient, which oscillations can be used to pump fluid. Any magnetic transition that results in a change in the vector nature of the magnetic moment of the soft magnetic material can be employed.
    Type: Grant
    Filed: June 13, 2014
    Date of Patent: October 18, 2016
    Assignee: Prime Photonics, LC
    Inventors: David Todd Gray, John Moore Coggin
  • Publication number: 20150346153
    Abstract: Methods of detecting non-uniformities in a material are described. Such methods can comprise inducing changes in strain state or changing the magnetic moment of a material and measuring magnetic flux leakage that is synchronous with the changes in strain state or magnetic moment, while simultaneously applying an external magnetic field to control the relative magnitude of the magnetic flux leakage.
    Type: Application
    Filed: May 21, 2015
    Publication date: December 3, 2015
    Inventors: Clark Davis Boyd, David Todd Gray, Jonathan Drapala Sides
  • Publication number: 20150083196
    Abstract: Provided is a magneto-thermoelectric generator (MTG) device for energy harvesting and more particularly a device for converting waste thermal heat from a photovoltaic cell into mechanical energy and ultimately into electrical energy. Embodiments operate on the principle of thermally-induced switching between open and closed states of a ferromagnetic switch to generate mechanical oscillations that cause strain in a piezoelectric material, resulting in the generation of electrical energy. A structure capable of providing a non-linear restoring force provides mechanical energy to the device, which is a significant improvement over prior art MTG devices employing a linear spring restorative force. The device is also provided as a hybrid photovoltaic (PV)/MTG energy harvester for scavenging heat from photovoltaic cells. The hybrid PV/MTG device is particularly useful for harvesting waste heat to boost power generation, extend flight duration, and provide thermal management aboard HALE platforms.
    Type: Application
    Filed: September 16, 2014
    Publication date: March 26, 2015
    Inventors: David Todd Gray, John Moore Coggin
  • Publication number: 20140366558
    Abstract: Magnetothermal pump devices are provided. Such devices can operate on the principle of thermally induced switching between open and closed states of a magnetic switch to generate mechanical oscillations. Exemplary devices provided include a thermal gradient and a magnet with a Curie temperature at or within this gradient. When the soft magnet is below the Curie temperature, it has sufficient magnetic force to bind a hard magnet at the hot side of the gradient. Heating of the magnet at the hot side causes it to exceed its Curie temperature, resulting in loss of magnetic attraction. At this stage, a restorative force exceeds the magnetic force, causing the magnet to shift to the cold side of the gradient, which oscillations can be used to pump fluid. Any magnetic transition that results in a change in the vector nature of the magnetic moment of the soft magnetic material can be employed.
    Type: Application
    Filed: June 13, 2014
    Publication date: December 18, 2014
    Inventors: David Todd Gray, John Moore Coggin