Patents by Inventor James W. Purvis

James W. Purvis 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: 11961666
    Abstract: The present invention discloses an electric field propulsion system for spacecraft. The system includes a capacitor stack comprising an array of supercapacitors. Solid-state electronic circuits generate modulated currents and electric fields in pulse coils. The pulse coils direct the electric fields onto separated electric charges stored in the capacitor stack. The resulting unidirectional Lorentz Forces thereby generate thrust without reaction mass. Reaction momentum is carried away by Poynting Vector fields in conformity with the currently understood principles of electrodynamics. The design is scalable down to micro-chip sized thrusters.
    Type: Grant
    Filed: August 6, 2020
    Date of Patent: April 16, 2024
    Inventor: James W. Purvis
  • Publication number: 20210159005
    Abstract: The present invention discloses a pulsed electric field propulsion system for spacecraft. The system includes a capacitor stack comprising an array of supercapacitors. Solid-state electronic circuits generate high time-rate-of-change currents and pulsed electric fields in pulse coils. The pulse coils direct the electric fields onto separated electric charges stored in the capacitor stack. The resulting unidirectional Lorentz Forces thereby generate thrust without reaction mass. Reaction momentum is carried away by Poynting Vector fields in conformity with the currently understood principles of electrodynamics. The design is scalable down to micro-chip sized thrusters.
    Type: Application
    Filed: August 6, 2020
    Publication date: May 27, 2021
    Inventor: James W. Purvis
  • Patent number: 9989336
    Abstract: The present invention discloses a projectile device for the nonlethal immobilization of threats. The invention includes a plurality of grappling-type hooking assemblies attached by a flexible means to a projectile core, a means for the dispersal of the hooking assemblies on or just prior to impact on a target, and a means for ballistically deploying the device from a 12 gauge shotgun, a 35 mm flare gun, a 40 mm grenade launcher, or other suitable launching device. In particular, the hooking assemblies disperse and adhere to the target, while the flexible attachment means entangle and either limit the motion of or immobilize the target.
    Type: Grant
    Filed: February 17, 2017
    Date of Patent: June 5, 2018
    Inventor: James W. Purvis
  • Publication number: 20170160060
    Abstract: The present invention discloses a projectile device for the nonlethal immobilization of threats. The invention includes a plurality of grappling-type hooking assemblies attached by a flexible means to a projectile core, a means for the dispersal of the hooking assemblies on or just prior to impact on a target, and a means for ballistically deploying the device from a 12 gauge shotgun, a 35 mm flare gun, a 40 mm grenade launcher, or other suitable launching device. In particular, the hooking assemblies disperse and adhere to the target, while the flexible attachment means entangle and either limit the motion of or immobilize the target.
    Type: Application
    Filed: February 17, 2017
    Publication date: June 8, 2017
    Inventor: James W. Purvis
  • Publication number: 20160254737
    Abstract: The present invention discloses systems and methods for electromagnetic propulsion. The electromagnetic propulsion or thrusting systems include two or more electromagnetic coils, a means for rotating one of the electromagnetic coils, and a means for periodically shaping the intensity. duration and polarity of magnetic fields from the coils. In particular, these systems and methods use the interaction between the angular acceleration components of the electromagnetic field generated by the rotating coil with the geometry of one or more stationary electromagnetic coils to achieve thrust without expelling mass.
    Type: Application
    Filed: February 26, 2015
    Publication date: September 1, 2016
    Inventor: James W. Purvis
  • Patent number: 7571493
    Abstract: A lightweight, armored protective garment for protecting an arm or leg from blast superheated gases, blast overpressure shock, shrapnel, and spall from a explosive device, such as a Rocket Propelled Grenade (RPG) or a roadside Improvised Explosive Device (IED). The garment has a ballistic sleeve made of a ballistic fabric, such as an aramid fiber (e.g., KEVLAR®) cloth, that prevents thermal burns from the blast superheated gases, while providing some protection from fragments. Additionally, the garment has two or more rigid armor inserts that cover the upper and lower arm and protect against high-velocity projectiles, shrapnel and spall. The rigid inserts can be made of multiple plies of a carbon/epoxy composite laminate. The combination of 6 layers of KEVLAR® fabric and 28 plies of carbon/epoxy laminate inserts (with the inserts being sandwiched in-between the KEVLAR® layers), can meet the level IIIA fragmentation minimum V50 requirements for the US Interceptor Outer Tactical Vest.
    Type: Grant
    Filed: August 4, 2005
    Date of Patent: August 11, 2009
    Assignee: Sandia Corporation
    Inventors: James W. Purvis, Jack F. Jones, II, Larry D. Whinery, Richard Brazfield, Catherine Lawrie, David Lawrie, Dale S. Preece
  • Patent number: 5632703
    Abstract: An infinitely variable transmission is capable of operating between a maximum speed in one direction and a minimum speed in an opposite direction, including a zero output angular velocity, while being supplied with energy at a constant angular velocity. Input energy is divided between a first power path carrying an orbital set of elements and a second path that includes a variable speed adjustment mechanism. The second power path also connects with the orbital set of elements in such a way as to vary the rate of angular rotation thereof. The combined effects of power from the first and second power paths are combined and delivered to an output element by the orbital element set. The transmission can be designed to operate over a preselected ratio of forward to reverse output speeds.
    Type: Grant
    Filed: August 4, 1995
    Date of Patent: May 27, 1997
    Assignee: Sandia Corporation
    Inventors: Donald F. Wilkes, James W. Purvis, A. Keith Miller