Patents by Inventor Douglas Spence

Douglas Spence 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).

  • Publication number: 20170369753
    Abstract: An electrospray thruster including an emitter, an extractor, a propellant storage vessel for a primary liquid propellant, a propellant delivery pathway from the vessel to the emitter, and an ionic liquid. The ionic liquid is configured to have a solid phase at temperatures less than a predetermined temperature and a liquid phase at temperatures greater than the predetermined temperature, and the ionic liquid is configured to create a propellant isolation barrier in the solid phase to prevent absorption by the primary liquid propellant. The electrospray thruster also includes a heater associated with the vessel and configured to heat the ionic liquid to above the predetermined temperature for mixing with the primary liquid propellant.
    Type: Application
    Filed: August 22, 2017
    Publication date: December 28, 2017
    Inventors: Nathaniel Demmons, Vladimir J. Hruby, Douglas Spence
  • Publication number: 20160333865
    Abstract: An electrospray thruster and method includes an emitter, an extractor, and a propellant storage vessel. A porous propellant delivery pathway from the vessel to the emitter wicks liquid propellant to the emitter. An ionic liquid in the vessel has a chemical composition rending the ionic liquid solid at room temperature to prevent water absorption. In the liquid state, the ionic liquid exhibits favorable electrospray characteristics. A heater associated with the vessel is configured to heat the ionic liquid to above its melting point when thrust is required for delivery to the emitter via the porous propellant delivery pathway.
    Type: Application
    Filed: April 8, 2016
    Publication date: November 17, 2016
    Inventors: Nathaniel Demmons, Vladimir J. Hruby, Douglas Spence
  • Publication number: 20160168437
    Abstract: A propellant isolation barrier including an ionic liquid is configured to have a solid phase at temperatures less than a predetermined temperature and a liquid phase at temperatures greater than the predetermined temperature. The ionic liquid is configured to create a propellant isolation barrier in the solid phase, mix with a primary liquid propellant in the liquid phase, and remain in the liquid phase and miscible with the primary liquid propellant at temperatures greater than and less than the predetermined temperature when mixed with the primary propellant.
    Type: Application
    Filed: November 20, 2014
    Publication date: June 16, 2016
    Inventors: Nathaniel Demmons, Vladimir J. Hruby, Douglas Spence
  • Patent number: 8448419
    Abstract: An electrospray source useful for a variety of applications and including an emitter with a porous media flow distributor having a surface forming multiple Taylor cones. A casing about the porous media flow distributor controls the direction of a working fluid through the porous media. An extractor is at a potential different than the emitter for forming the Taylor cones. A guard electrode is disposed between the emitter and the extractor and is at or above the potential of the emitter for shaping the electric field formed between the emitter and the extractor.
    Type: Grant
    Filed: August 18, 2008
    Date of Patent: May 28, 2013
    Assignee: Busek Company, Inc.
    Inventors: Nathaniel Demmons, Vlad Hruby, Douglas Spence, Thomas Roy
  • Patent number: 7932492
    Abstract: An electrospray device includes an electrospray emitter adapted to receive electrospray fluid; an extractor plate spaced from the electrospray emitter and having at least one aperature; and a power supply for applying a first voltage between the extractor plate and emitter for generating at least one Taylor cone emission through the aperature to create an electrospray plume from the electrospray fluid, the extractor plate as well as accelerator and shaping plates may include a porous, conductive medium for transporting and storing excess, accumulated electrospray fluid away from the aperature.
    Type: Grant
    Filed: July 14, 2009
    Date of Patent: April 26, 2011
    Assignee: Busek Co. Inc.
    Inventors: Nathaniel Demmons, Roy Martin, Vladimir Hruby, Thomas Roy, Douglas Spence, Eric Ehrbar, Jurg Zwahlen
  • Publication number: 20100025575
    Abstract: An electrospray device includes an electrospray emitter adapted to receive electrospray fluid; an extractor plate spaced from the electrospray emitter and having at least one aperature; and a power supply for applying a first voltage between the extractor plate and emitter for generating at least one Taylor cone emission through the aperature to create an electrospray plume from the electrospray fluid, the extractor plate as well as accelerator and shaping plates may include a porous, conductive medium for transporting and storing excess, accumulated electrospray fluid away from the aperature.
    Type: Application
    Filed: July 14, 2009
    Publication date: February 4, 2010
    Inventors: Nathaniel Demmons, Roy Martin, Vladimir Hruby, Thomas Roy, Douglas Spence, Eric Ehrbar, Jurg Zwahlen
  • Publication number: 20090113872
    Abstract: An electrospray source useful for a variety of applications and including an emitter with a porous media flow distributor having a surface forming multiple Taylor cones. A casing about the porous media flow distributor controls the direction of a working fluid through the porous media. An extractor is at a potential different than the emitter for forming the Taylor cones. A guard electrode is disposed between the emitter and the extractor and is at or above the potential of the emitter for shaping the electric field formed between the emitter and the extractor.
    Type: Application
    Filed: August 18, 2008
    Publication date: May 7, 2009
    Inventors: Nathaniel Demmons, Vlad Hruby, Douglas Spence, Thomas Roy