Patents Assigned to GT - Devices
  • Patent number: 5429030
    Abstract: A pressurized light gas in a first chamber segment of a light gas gun is heated and highly pressurized by an electric discharge. Solid chemical propellant in a second chamber segment behind and separated from the first chamber segment by a perforated wall is ignited by the heated and highly pressurized light gas to form a gaseous piston to assist in accelerating the light gas against a projectile.
    Type: Grant
    Filed: November 9, 1993
    Date of Patent: July 4, 1995
    Assignee: GT-Devices
    Inventor: Derek A. Tidman
  • Patent number: 5320382
    Abstract: An occupant passive restraint system for an automotive vehicle comprises an air bag and a pulsed pressure source in fluid flow relation with the air bag. The pulsed pressure source includes plural pulsed pressure sources sequentially energized in response to the deceleration sensor sensing a single crash impact. Each source includes plural chambers holding progressively larger masses of gas generant. The chambers are arranged so that each has an outlet coupled with the chamber having the next largest gas generant mass. The gas generant mass in each chamber is predominantly a non-explosive solid particulate material. The smallest chamber includes a fuse in contact with the generant. When a crash is sensed the fuse is supplied with a pulse having sufficient energy and duration to rupture the fuse and form a plasma discharge in the generant in the smallest chamber. The plasma discharge has sufficient energy to ignite the generant in the smallest chamber to a vapor.
    Type: Grant
    Filed: November 8, 1991
    Date of Patent: June 14, 1994
    Assignee: GT-Devices
    Inventors: Yeshayahu Shyke A. Goldstein, Melvin Widner
  • Patent number: 5072647
    Abstract: A projectile is accelerated through a gun barrel in response to high pressure gas applied to the rear of the projectile in response to a high pressure plasma discharge. Plasma from the discharge flows transversely of the discharge into a chamber through multiple openings in a passage wall that confines the discharge. The high pressure, high temperature plasma flowing into the chamber causes an exothermic reaction of water and metal particles in a slurry in the chamber to produce high pressure hydrogen gas that flows longitudinally of the discharge against the rear of the projectile. To maintain the pressure of hydrogen gas acting against the projectile relatively constant as the projectile is accelerated down the barrel, electric power applied to the discharge increases substantially linearly as a function of time.
    Type: Grant
    Filed: February 10, 1989
    Date of Patent: December 17, 1991
    Assignee: GT-Devices
    Inventors: Yeshayahu S. A. Goldstein, Derek A. Tidman, Dennis W. Massey, Joseph R. Greig
  • Patent number: 5033355
    Abstract: A pulsed high pressure, supersonic plasma jet for accelerating a projectile through an elongated confined bore is derived from a dielectric structure including a capillary passage having an interior wall surface from which plasma forming material is ablated in response to a discharge voltage applied to first and second electrodes respectively forming a nozzle and plug at opposite ends of the passage. The nozzle injects the plasma into the bore behind the projectile.
    Type: Grant
    Filed: January 27, 1986
    Date of Patent: July 23, 1991
    Assignee: GT-Device
    Inventors: Yeshayahu S. A. Goldstein, Derek A. Tidman
  • Patent number: 5012719
    Abstract: A projectile is accelerated through a barrel by a high pressure hydrogen gas jet that is derived by exothermically reacting water or a water-hydrogen peroxide liquid mixture with metal or a metal hydride. The temperature of the reaction is controlled by controlling the power in a plasma discharge applied to a reaction chamber containing the liquid and particles of the metal or metal hydride. A non-vaporous metal oxide resulting from the reaction is centrifugally separated from the hydrogen that drives the projectile.
    Type: Grant
    Filed: June 12, 1987
    Date of Patent: May 7, 1991
    Assignee: GT-Devices
    Inventors: Yeshayahu S. A. Goldstein, Derek A. Tidman, David Fleischer
  • Patent number: 5012720
    Abstract: A projectile is accelerated in a bore of a barrel by applying a plasma to the bore behind the projectile. The plasma has a tendency to occupy a volume in the bore behind a location in the bore where the plasma is applied. A magnetic field is applied to the plasma synchronously with application of the plasma to the bore for substantially preventing the plasma from flowing into the bore volume behind the location.
    Type: Grant
    Filed: August 29, 1989
    Date of Patent: May 7, 1991
    Assignee: GT-Devices
    Inventor: Derek A. Tidman
  • Patent number: 4974487
    Abstract: A projectile is accelerated in a barrel bore by applying a plasma jet to a projectile propelling fluid. The plasma jet is derived from a structure forming a capillary passage having a wall formed by a low molecular weight, dielectric powdery filler or water in many rigid containers, shaped as spheres or straw-like tubes having axes parallel to the passage longitudinal axis. The fluid and jet interact so the fluid is heated by the jet, whereby low atomic weight constituents of the fluid are sufficiently heated to become mixed with the plasma to form a high pressure mixture that is injected into the bore to accelerate the projectile. The fluid is dragged into the plasma during mixing to cool the plasma and form a boundary layer between the plasma and the barrel walls so that the mixture does not cause substantial damage to the walls of the bore. The plasma is energized by applying voltage from an electric pulse source to electrodes at opposite ends of the passage.
    Type: Grant
    Filed: October 3, 1988
    Date of Patent: December 4, 1990
    Assignee: GT-Devices
    Inventors: Yeshayahu S. A. Goldstein, Derek A. Tidman, Rodney L. Burton, Dennis W. Massey, Niels K. Winsor
  • Patent number: 4917335
    Abstract: Atmospheric drag and heating of the forwardmost portions of high speed transatmospheric vehicles and projectiles are reduced by lowering the atmospheric mass density immediately forward of a moving body. A fine high speed stream or jet of a material containing a chemically interactive component is ejected forwardly of such a body moving at high speed with respect to the atmosphere and, in a preferred embodiment of this invention ignites by interaction with the oncoming atmosphere and forms a sustained zone of combustion that, in effect, acts as a maintained "fireball" that explodes away ambient atmosphere transversely of the moving body so that there is generated a zone of low atmospheric density immediately in front of the forwardmost portion of the body. A supply of ejectable material and equipment for forcibly driving the same through a nozzle are carried with the body. The ejected material is preferably pressurized to render it flowable before ejection.
    Type: Grant
    Filed: March 31, 1988
    Date of Patent: April 17, 1990
    Assignee: GT-Devices
    Inventor: Derek A. Tidman
  • Patent number: 4913029
    Abstract: A high pressure plasma initially formed from a fluidizable substance in a confined region of a passage behind a projectile in the passage initially accelerates the projectile toward an open end of the passage. The plasma is intially derived by supplying a discharge current to an electrode in the substance. The plasma in the confined region is ohmically heated by an azimuthal current generated in the plasma by an AC magnetic field that is coaxial with the passage or by a discharge current flowing longitudinally through the passage and projectile. A cartridge includes the projectile and a wall of the passage that is evaporated after the projectile has been fired so the evaporant flows out of the passage after the projectile.
    Type: Grant
    Filed: November 12, 1986
    Date of Patent: April 3, 1990
    Assignee: GT-Devices
    Inventors: Derek A. Tidman, Yong C. Thio, Yeshayahu S. A. Goldstein
  • Patent number: 4907487
    Abstract: A high pressure plasma initially formed from a fluidizable substance in a confined region of a passage behind a projectile in the passage initially accelerates the projectile toward an open end of the passage. The plasma in the confined region is ohmically heated to a higher pressure by a discharge current flowing longitudinally through the passage and the projectile.
    Type: Grant
    Filed: November 12, 1986
    Date of Patent: March 13, 1990
    Assignee: GT-Devices
    Inventors: Derek A. Tidman, Yong C. Thio, Yeshayahu Shyke A. Goldstein
  • Patent number: 4901621
    Abstract: A rail gun projectile includes superconducting material. Current from a DC power supply flows between the rails through the superconducting material with a component at right angles to the elongated direction of the rails. The superconducting material is of a type that the current flowing through it produces a force for driving the projectile longitudinally along the rails. Metal abutting against the superconducting material shunts current from the power supply around a portion of the superconducting material having a tendency to go normal to the remainder of the superconducting material in the superconducting state.
    Type: Grant
    Filed: July 9, 1987
    Date of Patent: February 20, 1990
    Assignee: GT-Devices
    Inventor: Derek A. Tidman
  • Patent number: 4897558
    Abstract: A load is selectively supplied with current from an energy storing inductor shunted by a superconducting device. In the normal and superconducting states, the superconducting device respectively has an impedance greater than and much less than that of the load. Circulating current from the inductor flows through the device while it is in a superconducting state. The load is connected to the inductor and superconducting device so that when the device is in the normal state circulating current in the inductor is swtiched to flow from the device through the load. A solenoid wound on the superconducting structure responds to a current source to induce an axial magnetic field in the structure. The axial magnetic field induces in the structure an azimuthal current having sufficient density to change the device from the superconducting to the normal state.
    Type: Grant
    Filed: December 1, 1987
    Date of Patent: January 30, 1990
    Assignee: GT-Devices
    Inventor: Derek A. Tidman
  • Patent number: 4821508
    Abstract: A plasma electrothermal thruster includes a capillary passage in which a plasma discharge is formed and directed out of an open end of the passage into a supersonic nozzle. Liquid supplied to the capillary passage becomes partially atomized to cool a confining surface of the passage. The plasma discharge is formed as the atomized liquid flows out of the open end into a supersonic equilibrium nozzle. The discharge can have a duration greater than the two way travel time of acoustic energy in the capillary to cause the plasma to flow continuously through the nozzle during the time of the discharge pulse.
    Type: Grant
    Filed: June 10, 1985
    Date of Patent: April 18, 1989
    Assignee: GT-Devices
    Inventors: Rodney L. Burton, Yeshayahu S. A. Goldstein, Derek A. Tidman, Niels K. Winsor
  • Patent number: 4821509
    Abstract: A plasma electrothermal thruster includes a capillary passage in which a plasma discharge is formed and directed out of an open end of the passage into a supersonic nozzle. Liquid supplied to the capillary passage becomes partially atomized to cool a confining surface of the passage. The plasma discharge is formed as the atomized liquid flows out of the open end into a supersonic equilibrium nozzle. The discharge can have a duration greater than the two way travel time of acoustic energy in the capillary to cause the plasma to flow continuously through the nozzle during the time of the discharge pulse.
    Type: Grant
    Filed: December 7, 1987
    Date of Patent: April 18, 1989
    Assignee: GT-Devices
    Inventors: Rodney L. Burton, Yeshayahu S. A. Goldstein, Derek A. Tidman, Niels K. Winsor
  • Patent number: 4715261
    Abstract: A projectile is accelerated through a gun barrel bore by a cartridge containing a high temperature, high pressure plasma jet source. The cartridge has a geometry enabling it to be loaded into a breech bore of the gun. The plasma jet is supplied to the rear of the projectile and is derived by a tube having an interior wall forming a capillary passage. A discharge voltage applied between spaced regions along the capillary passage ionizes a dielectric to form a plasma. First and second ends of the passage are respectively open and blocked to enable and prevent the flow of plasma through them. The blocked end closes the breech bore.
    Type: Grant
    Filed: October 5, 1984
    Date of Patent: December 29, 1987
    Assignee: GT-Devices
    Inventors: Yeshayahu S. A. Goldstein, Derek A. Tidman, Rodney L. Burton, Dennis W. Massey, Niels K. Winsor
  • Patent number: 4670662
    Abstract: A pulse forming network, responsive to a DC power supply, supplies predetermined current waveforms to a load in response to commands from a programmed source. Plural inductors are connected to switches responsive to commands from the programmed source. The switches are controlled to couple the inductors to the DC source to charge the inductors to a predetermined current level that is maintained substantially constant. The predetermined current level in each inductor is supplied to the load by switches controlled by the programmed source so that during successive intervals the predetermined constant current levels from differing numbers of the inductors flow from the inductors to the load. The inductance of each inductor, the load impedance and the duration current is supplied to the load by the inductors are such that the predetermined current level supplied by each inductor to the load is maintained relatively constant.
    Type: Grant
    Filed: February 24, 1986
    Date of Patent: June 2, 1987
    Assignee: GT-Devices
    Inventors: Yeshayahu S. A. Goldstein, Niels K. Winsor
  • Patent number: 4590842
    Abstract: A projectile is accelerated along a confined path by supplying a pulsed high pressure, high velocity plasma jet to the rear of the projectile as the projectile traverses the path. The jet enters the confined path at a non-zero angle relative to the projectile path. The pulse is derived from a dielectric capillary tube having an interior wall from which plasma forming material is ablated in response to a discharge voltage. The projectile can be accelerated in response to the kinetic energy in the plasma jet or in response to a pressure increase of gases in the confined path resulting from the heat added to the gases by the plasma.
    Type: Grant
    Filed: March 1, 1983
    Date of Patent: May 27, 1986
    Assignee: GT-Devices
    Inventors: Yeshayahu S. A. Goldstein, Derek A. Tidman
  • Patent number: 4429612
    Abstract: An axi-symmetrical projectile, having a mass ranging from fractions of a gram to kilograms, is accelerated to velocities in the range of 10.sup.5 to 10.sup.7 centimeters per second by a propelling force produced by a plasma resulting from electric discharge. The discharge is imploded against the projectile surface so lines of the magnetic fields are approximately azimuthal around the projectile axis. The projectile is tapered so it experiences a net, stable axial accelerating force along the accelerator axis by the combined action of the magnetic field producing radially directed momentum and pressure on the plasma, the interaction of the magnetic field and ions induced by the plasma on the surface, as well as material the plasma ablates from the surface. The plasma discharge is initiated either in low density background gas between anode and cathode of a discharge module, or along an insulator surface between the electrodes in low density background gas.
    Type: Grant
    Filed: June 18, 1979
    Date of Patent: February 7, 1984
    Assignee: GT - Devices
    Inventors: Derek A. Tidman, Shyke A. Goldstein