Powder Grain Patents (Class 102/292)
  • Patent number: 11884604
    Abstract: The invention is in the field of propellants. In particular the invention is directed to a propellant for ammunition, such as medium and large caliber gun ammunition, having improved performance. In accordance with the present invention a propellant charge comprises one or more longitudinally extending, progressive-externally burning grains having a number of perforations passing through the grains in the length direction and having a cross-sectional shape (perpendicular to the grain's length direction) that is elongated.
    Type: Grant
    Filed: September 12, 2016
    Date of Patent: January 30, 2024
    Assignee: NEDERLANDSE ORGANISATIE VOOR TOEGPAST-NATUURWETENSCHAPPELIJK ONDERZOEK TNO
    Inventors: Christoffel Adrianus van Driel, Dinesh Ravindre Ramlal, Martijn Zebregs, Michiel Hannes Straathof
  • Patent number: 10125057
    Abstract: For production of a propellant charge powder, especially for medium and large calibers, in a process in which the solid is incorporated together with a liquid in a mixing and drying process into the channels of a granular green material and compacted therein to form a plug, the solid, under otherwise identical process conditions, is set within a setting range of >0-0.5% by weight based on the weight of the granular green material. For more significant lowering of the maximum pressure within an upper temperature range and for more significant raising of the maximum pressure within a lower temperature range of the application temperature range, an increased amount of solid is used. The solid is a substance whose melting point is at least 10° C., especially 20° C., above a maximum use temperature of the propellant charge powder and which is inert toward the granular green material. Since the plug consists virtually exclusively of inert material, a high ballistic stability is achieved.
    Type: Grant
    Filed: March 28, 2012
    Date of Patent: November 13, 2018
    Assignee: NITROCHEMIE ASCHAU GMBH
    Inventors: Beat Vogelsanger, Bruno Ossola, Alexander Huber, Christian Wagner, Oliver Hampel
  • Publication number: 20140238678
    Abstract: Propellant structures and stimulation tools incorporating propellant structures may comprise composite propellant structures including two or more regions of propellant having different compositions, different grain structures, or both. An axially extending initiation bore containing a initiation element may extend through a center of the propellant structure, or may be laterally offset from the center. An offset initiation bore may be employed with a composite grain structure. Methods of tailoring ballistic characteristics of propellant burn to result in desired operational pressure pulse characteristics are also disclosed.
    Type: Application
    Filed: February 28, 2013
    Publication date: August 28, 2014
    Inventors: JOHN A. ARRELL, JR., STEVEN E. MOORE
  • Patent number: 8460575
    Abstract: The invention is directed to a solid, porous material, suitable for generating nitrogen gas, said material having a porosity of 20 to 75 vol. %, and a composition comprising, based on the weight of the material of 60 to 90 wt. % of sodium azide, 0.1 to 20 wt. % of an inert chemical coolant based on at least one inorganic salt having a heat capacity of at least 1400 J/K/kg, 0.1 to 20 wt. % of modifying agent selected from metal oxides and metal carbonates, and a binder, selected from the group consisting of at least one alkali metal silicate, preferably waterglass, or a poly-tetrazole, in an amount of between 3 and 15 wt. %.
    Type: Grant
    Filed: December 5, 2008
    Date of Patent: June 11, 2013
    Assignee: Nederlandse Organisatie voor toegepast-natuurwetenschappelijk onderzoek TNO
    Inventor: Laurens Daniël van Vliet
  • Patent number: 8156869
    Abstract: The present invention relates to a method of producing propellant charges (2) of multi-perforated stick propellant with maximized charge weights for sub-calibre, armour-piercing, high-velocity projectiles (3), which are provided, for example, with six to eight, fixed stabilizing fins (5-10). The invention also encompasses a multi-perforated stick propellant (11-12) intended for this purpose and a propellant charge produced from multi-perforated stick propellant according to the methods.
    Type: Grant
    Filed: April 11, 2007
    Date of Patent: April 17, 2012
    Assignee: Eurenco Bofors AB
    Inventor: Johan Dahlberg
  • Patent number: 7051658
    Abstract: The proposed propellant powder exhibits a temperature-independent burning behavior and high ballistic stability. The production process starts with a perforated bulk powder grain, which is processed inside a mixing apparatus with a solid material, a plug-stabilizing moderator or deterrent (if necessary also a radical initiator) and a low-viscous liquid. With a minimum amount of solid material, moderator or deterrent and liquid and because of the continuous mixing, the form function is influenced in such a way that the gas-formation rate is practically independent of the propellant powder temperature. As a result, the muzzle energy at the normal temperature and, above all, at a low deployment temperature can be increased markedly as compared to that of a standard propellant powder.
    Type: Grant
    Filed: March 13, 2002
    Date of Patent: May 30, 2006
    Assignees: Nitrochemie Wimmis AG, Nitrochemie Aschau GmbH
    Inventors: Markus Fahrni, Beat Vogelsanger, Alfred Steinmann, Bruno Ossola, Ulrike Jeck-Prosch, Alexander Huber, Kurt Ryf
  • Patent number: 6647888
    Abstract: An oxidizer package for a propellant system for a motor in which the oxidizer is separated from fuel grain, the oxidizer package comprising oxidizer material and an ignition system therefor in a wrapping or sealing material. A hybrid rocket comprising oxidizer material and fuel grain, the oxidizer material being separated from the fuel grain and being in the form of a single package or plurality of packages of oxidizer material and an ignition system therefor, said packages generally conforming to the shape of the rocket. A grid of a pyrotechnic material. A propulsion system for a hybrid rocket comprising oxidizer material in a matrix, mesh, wool, foamed metal or wires of structural or pyrotechnic material.
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: November 18, 2003
    Inventors: Anthony Joseph Cesaroni, Michael J. Dennett, Korey R. Kline, Kevin E. Mahaffy, Kevin W. Smith
  • Patent number: 6527886
    Abstract: A gas-generant-molded-article for air bags which is prepared by molding a gas generant composition into a cylindrical form containing an opening hole, wherein the relationship between the linear burning velocity r (mm/second) of said gas generant composition under a pressure of 70 kgf/cm2 and a thickness W (mm) of said molded article falls within a range represented by 0.005≦W/(2·r)≦0.3, with the linear burning velocity preferably falling within a range of from 1 to 12.5 mm/second.
    Type: Grant
    Filed: March 31, 1997
    Date of Patent: March 4, 2003
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Yo Yamato, Norimasa Hirata, Takeshi Takahori, Takushi Yokoyama, Naoki Matsuda
  • Publication number: 20020062756
    Abstract: A propellant grain for a cylindrical casing has a cavity including an axially central opening with a combustion product exit port at one end. The grain bears a plurality of surfaces extending circumferentially about and disposed normally or helically to this opening so as to define, between these surfaces and axially of the casing, alternating sections of propellant and sections of a groove or grooves in the propellant. The groove sections extend radially from the opening to a distance selectable to provide the grain with a large initial surface area while providing a high propellant volume. The port area may be selected to be relatively large in relation to the area of an adjacent discharge nozzle, and the grain may be made substantially neutral burning by selecting the distance from the groove radial ends to the casing to be about twice the axial thickness of a section of propellant between adjacent groove sections.
    Type: Application
    Filed: November 30, 2000
    Publication date: May 30, 2002
    Inventor: Harry L. Archer
  • Patent number: 6378436
    Abstract: A propellant cutting assembly and method of using the assembly to cut samples of solid propellant in a repeatable and consistent manner is disclosed. The cutting assembly utilizes two parallel extension beams which are shorter than the diameter of a central bore of an annular solid propellant grain and can be loaded into the central bore. The assembly is equipped with retaining heads at its respective ends and an adjustment mechanism to position and wedge the assembly within the central bore. One end of the assembly is equipped with a cutting blade apparatus which can be extended beyond the end of the extension beams to cut into the solid propellant.
    Type: Grant
    Filed: February 18, 2000
    Date of Patent: April 30, 2002
    Assignee: Cordant Technologies Inc.
    Inventors: Roger A. Sharp, Shawn W. Hoskins, Brett D. Payne
  • Patent number: 6352029
    Abstract: This invention relates to explosive charges in which the chemical and physical composition changes gradually from point to point in order to accomplish differing, specific design objectives. More specifically, the invention relates to an explosive comprised by uniformly mixing components of differing chemical and physical properties in order to take advantage of the functions performed by these different components resulting in an explosive capable of performing multiple or specific tasks.
    Type: Grant
    Filed: March 30, 2000
    Date of Patent: March 5, 2002
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Raafat H. Guirguis, John M. Kelley
  • Publication number: 20010000383
    Abstract: A gas-generant-molded-article for air bags which is prepared by molding a gas generant composition into a cylindrical form containing an opening hole, wherein the relationship between the linear burning velocity r (mm/second) of said gas generant composition under a pressure of 70 kgf/cm2 and a thickness W (mm) of said molded article falls within a range represented by 0.005≦W/(2·r)≦0.3, with the linear burning velocity preferably falling within a range of from 1 to 12.5 mm/second.
    Type: Application
    Filed: December 20, 2000
    Publication date: April 26, 2001
    Applicant: Daicel Chemical Industries, Ltd.
    Inventors: Yo Yamato, Norimasa Hirata, Takeshi Takahori, Takushi Yokoyama, Naoki Matsuda
  • Patent number: 6167810
    Abstract: The invention provides an improved propellant system for firing projectiles in large caliber guns. Strips of energetic propellant are placed in the cartridge case so that the lengths of the strips are parallel to the length of the cartridge. Preferably, the strips are placed in a radially symmetric pattern. The strips provide passageways that allow ignition gasses to flow radially in the cartridge case and along the length of the cartridge case.
    Type: Grant
    Filed: December 4, 1998
    Date of Patent: January 2, 2001
    Assignee: United Defense, L.P.
    Inventors: Brian J. Isle, Gerald L. Dittmann, Amir Chaboki, Steven R. Zelenak, Timothy W. Petersen
  • Patent number: 6110307
    Abstract: The present invention relates to a compacting process suitable particularly for the compacting of materials with a pyrophoric tendency and especially for the compacting of scrap metal generated in the nuclear industry: and compacting means (4), and a compacting device including said means (4), appropriate for the implementation of said process. In said process the blanketed materials are compacted with optimized complementary external blanketing. The inert gas used for said external blanketing is characteristically conveyed via the compacting means (4) and blown in through their lower end (15).
    Type: Grant
    Filed: December 10, 1999
    Date of Patent: August 29, 2000
    Assignee: Compagnie Generale des Matieres Nucleaires
    Inventors: Jean-Claude Guerin, deceased, by Robert Rene Armand Guerin, heir, by Christiane Guerin, heir, by Jean-Baptiste Guerin, heir, by Agnes Fernande Cano, heir, by Pierre Emmanuel Guerin, heir, Philippe Kerrien, Gerard Limeuil
  • Patent number: 5996501
    Abstract: A dual explosive charge is described that simultaneously enhances blast and fragmentation characteristics of the charge, including an inner driven charge of a non-ideal explosive surrounded by an outer charge sleeve of a more nearly ideal explosive, detonation of the outer charge resulting in an extremely high temperature, high pressure environment that accelerates reaction kinetics in the inner charge, resulting in enhanced blast and fragmentation performance of the explosive charge.
    Type: Grant
    Filed: August 27, 1997
    Date of Patent: December 7, 1999
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Arthur F. Spencer, John D. Corley
  • Patent number: 5925846
    Abstract: A method of increasing the water resistance of a blasting explosive comprising an organic carbonaceous fuel, an inorganic oxidizing salt having a particular particle size distribution and a gelling agent comprising the step of adding to the blasting explosive a particulate filler material. The particle size distribution of the particulate filler material and the inorganic oxidizing salt are selected to increase the water resistance of the blasting explosive.
    Type: Grant
    Filed: May 28, 1996
    Date of Patent: July 20, 1999
    Assignee: ETI Canada
    Inventors: Andrew Richard, Grant Simpson, Earl Reckzin
  • Patent number: 5892172
    Abstract: An improved geometric propellant loading configuration for high velocity, large or medium caliber projectile ammunition is disclosed. The propellant system includes several mutually contiguous extrudable stick shapes that in concert result in highly efficient use of propellant load space. The system reduces loading, assembling and packing (LAP) labor and overall cost, yet provides a dense pattern to increase propellant load and high perforation to improve burning progressivity over prior stick loads and more reliable and improved ballistic performance.
    Type: Grant
    Filed: April 22, 1997
    Date of Patent: April 6, 1999
    Assignee: Alliant Techsystems Inc.
    Inventors: Calvin T. Candland, James L. Kennedy
  • Patent number: 5668345
    Abstract: A hybrid inflator has porous substrate coated with a heat-producing, essentially non gas-producing composition for heating pressurized inflation gases in the inflator.
    Type: Grant
    Filed: October 19, 1995
    Date of Patent: September 16, 1997
    Assignee: Morton International, Inc.
    Inventors: David D. Schroeder, Brett Hussey, Walter A. Moore
  • Patent number: 5650589
    Abstract: A cartridge ammunition includes a case having a case bottom; a propellant disposed in the case; a propellant igniter mounted centrally on the case bottom; an arrow projectile having a rear length portion extending into the case towards the case bottom; and a coating of igniting substance applied to at least one part of the surface of the rear projectile length portion. A clearance defined by a distance between a frontal terminus of the propellant igniter and the rear terminus of the rear length portion of the arrow projectile is such that upon igniting the propellant igniter igniting flames emanating from the propellant igniter bridge the clearance and ignite the coating of igniting substance.
    Type: Grant
    Filed: December 21, 1995
    Date of Patent: July 22, 1997
    Assignee: Rheinmetall Industrie GmbH
    Inventor: Stefan Thiesen
  • Patent number: 5635666
    Abstract: A flare mass for dummy target production has an incendiary composition component and an inert component, the weight ratio of the incendiary mass component and the inert component being adjusted such that the maximum of the spectral radiant flux of the flare mass in adaptation to the spectral radiant flux distribution of the target signature to be simulated is displaced toward longer wavelengths compared with the spectral radiant flux distribution of the incendiary mass component alone.
    Type: Grant
    Filed: June 12, 1995
    Date of Patent: June 3, 1997
    Assignee: Buck Werke GmbH & Co.
    Inventors: Heinz Bannasch, Martin Wegscheider, Martin Fegg, Horst Bosel
  • Patent number: 5610365
    Abstract: A cartridge ammunition includes a case having a case bottom; a propellant powder disposed in the case, a propellant igniter mounted centrally on the case bottom; and an arrow projectile having a rear length portion extending into the case towards the case bottom. At least those grains of the propellant powder which are situated axially beyond the propellant igniter are coated with an igniting substance.
    Type: Grant
    Filed: December 21, 1995
    Date of Patent: March 11, 1997
    Assignee: Rheinmetall Industrie GmbH
    Inventor: Stefan Thiesen
  • Patent number: 5602360
    Abstract: An electronic delay igniter including a firing capacitor (102) for storing energy required for firing by applying a voltage from an external power supply, an electronic timer unit (206) provided with a solid state oscillator driven by the energy stored in the firing capacitor (102) to output an output signal after a predetermined delay time, a switching unit (104) for receiving the output signal to transmit the firing energy to an ignition unit (107), and the ignition unit (107) having a ignition charge which ignites on receiving the firing energy, a voltage from the external power supply has a voltage application region where the electronic timer (206) is operated to operate the switching unit (104), but the ignition charge does not ignite even when the energy from the firing capacitor (102) is received.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: February 11, 1997
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Midori Sakamoto, Masaaki Nishi
  • Patent number: 5597973
    Abstract: A signal transmission fuse (10, 20) such as shock tube has an outside diameter (OD) not greater than about 2.380 mm (0.0937 inch), for example, a tube outside diameter (OD) of from about 0.397 to 2.380 mm (about 0.0156 to 0.0937 inch), and the ratio of the inside diameter (ID) of the tube to the radial thickness of the tube wall (T) is from about 0.18 to 2.5. The inside diameter (ID) of the tube may be from about 0.198 to 1.321 mm (about 0.0078 to 0.0520 inch). The powder surface density of the reactive material contained within the bore (16, 30) of the fuse (10, 20) may, but need not, be significantly less than that which the prior art considers to be a minimum acceptable powder surface density.
    Type: Grant
    Filed: January 30, 1995
    Date of Patent: January 28, 1997
    Assignee: The Ensign-Bickford Company
    Inventors: Ernest L. Gladden, Gary R. Thureson, Alvaro Zappalorti, Eric R. Davis, Frank J. Lucca
  • Patent number: 5551343
    Abstract: A gas generant body having a plurality of alike, flat-surfaced projections equally spaced and radially equidistant about the periphery of one or both sides of the body. The spaced projections are defined by curved or arcuate walls emanating from the center of the generant body which flare outwardly to the body's perimeter, each having an angular arc length greater than the space therebetween. The outer edge of each projection is preferably contiguous with the perimeter of the body. When the projections are on both sides, as is preferred, the projections on one side are preferably in a staggered or offset relationship to those on the other side. A washer-shaped wafer disc is the most preferred overall generant body form. A stack or assembly of the multiprojection generant wafers may be formed into an array for use in a gas generator for an automobile gas bag inflator.
    Type: Grant
    Filed: January 21, 1994
    Date of Patent: September 3, 1996
    Assignee: Morton International, Inc.
    Inventors: Christopher Hock, Brian T. Snyder, Linda M. Rink, Guy R. Letendre
  • Patent number: 5501152
    Abstract: A spontaneous ignition agent for an air bag gas generator with excellent temperature resistance comprises essentially nitrocellulose, an inorganic oxidizing agent, and carbon.
    Type: Grant
    Filed: December 29, 1993
    Date of Patent: March 26, 1996
    Assignee: Temic Bayern-Chemie Airgab GmbH
    Inventors: Siegfried Zeuner, Hans-Peter Ruge, Peter Neukirchinger
  • Patent number: 5447104
    Abstract: A galvanically conductive explosive is formed by the admixture of a small proportion of precious metal-containing platelets to a binder. The resulting blend is combined with explosive granules to form a homogeneous mixture which, after press-forming, produces galvanically conductive bodies.
    Type: Grant
    Filed: October 26, 1993
    Date of Patent: September 5, 1995
    Assignee: Schweizerische Eidgenossenschaft Vertreten Durch Die Eidg. Munitionsfabrik Thun Der Gruppe Fur Rustungsdienste
    Inventors: Francis Lebet, Jorg Mathieu
  • Patent number: 5388519
    Abstract: A low toxicity primer composition is provided incorporating a heavy-metal free primer explosive sensitizer, metallic fuel and an oxidizer selected from an oxidizer selected from the group consisting of cesium nitrate, strontium sulfate, strontium oxalate, sodium oxalate, nitroguanadine, guanadine nitrate, penthrite, zirconium oxide, and mixtures thereof.
    Type: Grant
    Filed: July 26, 1993
    Date of Patent: February 14, 1995
    Assignee: SNC Industrial Technologies Inc.
    Inventors: Louise Guindon, Danielle Allard
  • Patent number: 5333550
    Abstract: A binary, ternary and/or quaternary tin alloy composition that may be used as outer sheath material in various explosive-pyrotechnic linear products, such as ignition cord, mild detonating cord (MDC) and linear shaped charge (LSC).
    Type: Grant
    Filed: July 6, 1993
    Date of Patent: August 2, 1994
    Assignee: Teledyne McCormick Selph
    Inventors: Stanley Rodney, Larry H. Barr
  • Patent number: 5325782
    Abstract: A gun propellant having reduced sensitivity to impact and improved burning ate, comprising crystallized NNHT particles admixed with a binder and at least one plasticizer. In a preferred embodiment, the binder is a nitrocellulose binder and the plasticizer is a liquid nitramine plasticizer. A preferred liquid nitramine plasticizer is selected from the group of ethyl nitrato ethyl nitramine and methyl nitrato ethyl nitramine. The propellant of this invention may be used or alone or may also include a quantity of RDX propellant. The propellant is suitable to be formulated for an artillery application or for a tank system.
    Type: Grant
    Filed: July 20, 1993
    Date of Patent: July 5, 1994
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Bernard Strauss, Sam M. Moy
  • Patent number: 5320043
    Abstract: The invention relates to a low-vulnerability explosive munitions element comprising a casing containing a multicomposition explosive charge, the innermost layer of which is a composite explosive comprising a filled polyurethane or polyester polymer matrix, the filling of which contains more than 20% by weight of organic nitrate explosive, and the peripheral layer of which is a pyrotechnic composition of the family of composite solid propellants comprising a filled polyurethane or polyester polymer matrix the filling of which contains at least one mineral oxidant and less than 17% by weight of organic nitrate explosive. The blast and/or bubble effect produced is close to that produced by the much more-vulnerable charge of monocomposition composite explosive of equivalent mass. The invention also relates to a method for obtaining a blast and/or bubble effect by releasing in the casing of an aforementioned munitions element according to the invention, and then rupture of the casing.
    Type: Grant
    Filed: January 29, 1993
    Date of Patent: June 14, 1994
    Assignee: SNPE Inc.
    Inventors: Michel Andre, Jean-Pierre Mazer, Bruno Nouguez
  • Patent number: 5269224
    Abstract: A unitary propellant charge module for use in separate ammunition comprises a combustible container having a generally hollow cylindrical shape, a generally cylindrical charge body of interconnected compacted spheroidal propellant grains disposed within the container, each of the grains having an uncompacted propellant grain diameter of at least 100 mils, and at least one generally tubular center core igniter body of interconnected compacted spheroidal propellant grains having an unrolled grain size between about 20 to less than 100 mils in diameter. The igniter body is disposed within a central bore extending along the longitudinal axis of the charge body.
    Type: Grant
    Filed: June 2, 1992
    Date of Patent: December 14, 1993
    Assignee: Olin Corporation
    Inventors: Antonio Gonzales, Henry H. Raines
  • Patent number: 5189249
    Abstract: An insensitive gel propellant composition based on a fine-particle detonating high explosive which contains from about 10 to 15 wt. % water, and which will not ignite until subjected to a temperature of about 900 psi.
    Type: Grant
    Filed: November 14, 1991
    Date of Patent: February 23, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: William C. Burkhardt, Michael W. Diehl, Wesley F. Spence
  • Patent number: 5189247
    Abstract: The invention relates to a low-vulnerability explosive munitions element comprising a casing containing a multicomposition explosive charge, the innermost layer of which is a composite explosive comprising a filled polyurethane or polyester polymer matrix, the filling of which contains more than 40% by weight of organic nitrate explosive, and the peripheral layer of which is a pyrotechnic composition of the family of composite solid propellants comprising a filled polyurethane or polyester polymer matrix the filling of which contains at least one mineral oxidant and less than 10% by weight of organic nitrate explosive. The blast and/or bubble effect produced is close to that produced by the much more-vulnerable charge of monocomposition composite explosive of equivalent mass. The invention also relates to a method for obtaining a blast and/or bubble effect by releasing in the casing of an aforementioned munitions element according to the invention, and then rupture of the casing.
    Type: Grant
    Filed: July 31, 1991
    Date of Patent: February 23, 1993
    Assignee: SNPE Inc.
    Inventors: Michel Andre, Jean-Pierre Mazer, Bruno Nouguez
  • Patent number: 5114630
    Abstract: Fluid products, particularly highly filled materials, are manufactured and cast in a continuous system utilizing feedforward composition quality control and plug flow. Liquid and solid raw are supplied to, and combined in, a continuous fluid flow system in which plug flow is established. Quantities of materials supplied are measured and averaged over time to determine composition proportions, which are compared to specification. Running averages are maintained for successive serial portions of the continuous plug flow stream. In-specification product is diverted to casting and off-specification to waste, after a time delay so that appropriate diversion is accomplished for each particular, composition-determined serial portion of the product flowstream.
    Type: Grant
    Filed: September 21, 1990
    Date of Patent: May 19, 1992
    Assignee: The United of America as represented by the Secretary of the Navy
    Inventors: Kirk E. Newman, James A. Gusack, John A. Zehmer, III
  • Patent number: 5081930
    Abstract: A gun propellant comprises ammonium azide in finely divided form and at least one conventional propellant and/or explosive composition. The ammonium azide is free of any heavy metals capable of reacting with the ammonium azide to form metallic azides. The ammonium azide may be in pulverulent form or may be fabricated into a grain having a specific geometry. The ammonium azide may also be employed as a pyrotechnic formulation in a variety of environments.
    Type: Grant
    Filed: March 13, 1990
    Date of Patent: January 21, 1992
    Assignee: Martin Marietta Corporation
    Inventor: Laurence O. Williams
  • Patent number: 5074938
    Abstract: Propellant grain consisting essentially of:A. from about 50% to about 75% by weight of an oxidizer consisting essentially of ammonium nitrate;B. from about 1% to about 20% by weight of a cured polymeric binder;C. from 0% to about 30% by weight of a nitrate ester plasticizer;D. from about 3.5% to about 8% by weight of boron in free elemental form; andE. from 0% to about 3% by weight of aluminum metal.The grain has a pressure exponent not exceeding about 0.30 at a combustion pressure between about 2500 and about 7000 pounds per square inch (between about 1700 and about 4800 N/cm.sup.2). Also, an uncured pourable slurry having the formula stated above, except that the binder is uncured. Also, a method for forming a propellant grain having the formula stated above, comprising the steps of providing the uncured pourable slurry defined above, pouring the slurry into a casing, and curing the slurry in situ to form a cured propellant grain having a pressure exponent not exceeding about 0.
    Type: Grant
    Filed: May 25, 1990
    Date of Patent: December 24, 1991
    Assignee: Thiokol Corporation
    Inventor: Minn-Shong Chi
  • Patent number: 4949095
    Abstract: A new and improved fused silica radome is discussed. The radome has a density equal to or greater than 95 percent of theoretical density, an average bend strength equal to or greater than 10 Kpsi, a thermal expansion of about 0.3.times.10.sup.-6 .degree. C., a dielectric constant of about 3.8 at X-Band frequencies, a loss tangent of about 0.002 at X-Band frequencies, an average modulus of rupture greater than 10 Kpsi from room temperature to 1000.degree. C., and no crystalline phase present. The radome is made by an arc fusion process in which a quartz powder is placed within a graphite mold, then shaped by centrifugal force as the mold is rotated. An arc is then struck between electrodes within the mold cavity. The quartz powder fuses to form a dense silica radome which is removed from the mold after the fusion occurs.
    Type: Grant
    Filed: November 29, 1988
    Date of Patent: August 14, 1990
    Assignee: GTE Laboratories Incorporated
    Inventors: Jeffrey T. Neil, Leslie J. Bowen, Brett E. Michaud
  • Patent number: 4920079
    Abstract: A water-filled pressure chamber (7) loaded by conventional pumps at pressures of several thousand bars is used to isostatically press explosive charges. Inside this pressure chamber (7) is a compression mold (6) having an inner/outer mold (1) consisting of several components. Explosives in the mold are subjected through an elastic sleeve (3) to liquid pressure (p), so that the interior pressure in the chamber will be nearly isostatic. Following pressure relief, Dimensionally accurate and homogeneous precision explosive charges are obtained.The present invention also includes the process using the pressure chamber. The invention increases manufacturing output and quality of explosive charges so produced.
    Type: Grant
    Filed: June 8, 1988
    Date of Patent: April 24, 1990
    Assignee: Schweizerische Eidgenossenschaft Vertreten Durch: Eidg. Munitionsfabrik Thun Der Gruppe Fur Rustensdienste
    Inventors: Rudolf Kaeser, Jurg Meister
  • Patent number: 4911077
    Abstract: The disclosure relates to a method of producing charges for cannons with extremely high charge density and favorable burning properties from the standpoints of both wear and pressure vs time characteristics. According to the invention, the charge is formed of mutually parallel, bundled tubular propellant rods which have been provided with specially designed rupture points which cause the charge to be ignited as a pure tubular propellant charge of large length in relation to the diameter of the combustion channels, but finally burns as a pure granular propellant. The disclosure also relates to propellant charges produced according to the disclosed method.
    Type: Grant
    Filed: August 19, 1988
    Date of Patent: March 27, 1990
    Assignee: Nobel Kemi AB
    Inventors: Lennart Johansson, Mats Olsson, Torsten Persson
  • Patent number: 4876962
    Abstract: The disclosure relates to a propellant charge for cannons comprising bundles (11) of tightly held tubular propellant sticks which are provided with connections between the propellant sticks' outer surfaces and their combustion channels, these connections consisting of either longitudinal slits or of uniformly spaced, weakened points in the form of perforations, slits, open notches or bored holes which extend from the outer surfaces of the propellant sticks to the combustions channels, the bundles (11) being surrounded by disoriented powder flakes, powder grains or short powder rods or tubes (9), these filling the remaining portion of the combustion space (7).The disclosure also relates to a method of producing such a charge.
    Type: Grant
    Filed: August 3, 1988
    Date of Patent: October 31, 1989
    Assignee: Nobel Kemi AB
    Inventor: Mats Olsson
  • Patent number: 4758287
    Abstract: A process for preparing a porous propellant grain which comprises blending at least two combustible materials to form a homogeneous mixture, adding a predetermined amount of a liquid dispersant to said mixture to form a slurry, and flash drying the slurry in order to form a porous, single grain propellant having a greatly increased burning surface. A single grain propellant is produced having a flat, torroidal shape with a central cylindrical core and honeycombed with a plurality of porous channels extending entirely through the grain to increase the burning surface thereof.
    Type: Grant
    Filed: June 15, 1987
    Date of Patent: July 19, 1988
    Assignee: Talley Industries, Inc.
    Inventor: John F. Pietz
  • Patent number: 4736683
    Abstract: The invention relates generally to explosives, and more particularly to dry ammonium nitrate-fuel oil based explosives, containing a high molecular weight polymer characterized by a high stringiness factor.
    Type: Grant
    Filed: August 5, 1986
    Date of Patent: April 12, 1988
    Assignee: Exxon Chemical Patents Inc.
    Inventors: Harold E. Bachman, Ralph S. Totman
  • Patent number: 4729317
    Abstract: An air-breathing solid fuel rocket motor containing a solid fuel ramjet gn having a plurality of concentric layers of solid fuel which provide a means of controlling the thrust of the motor.
    Type: Grant
    Filed: December 8, 1986
    Date of Patent: March 8, 1988
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: George W. Burdette, John P. Francis
  • Patent number: 4722814
    Abstract: A propellent charge for cartridge ammunition of propellent powder bodies of a certain geometric form is produced by filling the propellent powder bodies preferably in partial amounts and by means of a suitable funnel into the propellent case and compressing them there without the addition of binders and/or solvents up to a charge density 1.0 to 1.5 g/cc, and that they are shaped elastically to plasticity under substantially uniform and/or gradually varying compression.
    Type: Grant
    Filed: February 14, 1983
    Date of Patent: February 2, 1988
    Assignee: Mauser-Werke Oberndorf GmbH
    Inventors: Gero Waehner, Michael Korn, Dieter Fichter, Heinrich Brachert, Dieter Girke, Johan Kobes
  • Patent number: 4710329
    Abstract: A method and a mould for manufacturing articles of compacted powder by isostatic compression of powder in a mould, which is made of flexible material of substantially constant thickness and is substantially barrel-shaped, the mould having at one end a bottom made integral with the rest of the mould and being adapted to be closed by a separate plug at its other end.
    Type: Grant
    Filed: May 16, 1984
    Date of Patent: December 1, 1987
    Assignees: Basset Bretagne Loire - B.B.L., Societe Nationale des Poudres et Explosifs
    Inventors: Jean-Marie Lebas, Pierre Rat, Jean-Marcel Dupont, Germain Vinuesa
  • Patent number: 4696705
    Abstract: Structure for generating nitrogen gas for inflating an air bag vehicle occupant restraint comprises a grain made of an azide based material which generates gas upon combustion. The grain is made of a gas generating material which includes 61-68% by weight of sodium azide, 0-5% by weight of sodium nitrate, 0-5% by weight of bentonite, 23-28% by weight of iron oxide, 1-2% by weight of fumed silica, and from about 2 to about 6% by weight of graphite fibers having a diameter of 3-15 microns and an average length of 40 to 125 thousandths of an inch.
    Type: Grant
    Filed: December 24, 1986
    Date of Patent: September 29, 1987
    Assignee: TRW Automotive Products, Inc.
    Inventor: Brian K. Hamilton
  • Patent number: 4654093
    Abstract: The invention relates to a general method of producing progressively burning deterrent-coated powder, more particularly propellant powder for weapons having barrels. According to the method a film-forming, preferably polymerizable deterrent substance is fed to the powder loosely or dispersed in a liquid phase which is thereafter driven off. The invention also relates to a method of giving a deterrent coating to granular powder or powder cut up in to short pieces (so-called tubular powder) in a fluidized bed. Finally, the invention relates to a special deterrent substance in the form of a water-dispersable polyurethane built up on an aliphatic isocyanate and a caprolacton polyester.
    Type: Grant
    Filed: January 14, 1986
    Date of Patent: March 31, 1987
    Assignee: Aktiebolaget Bofors
    Inventors: Boo Bolinder, Hermann Schmid
  • Patent number: 4627352
    Abstract: A single- or multiple-base powder charge for propellants is made up of at least one powder grain in the form of a shaped mass of powder having at least one internal cavity. The diameters of the internal cavities within the powder grains making up the charge are different and at least a portion thereof is smaller than the critical diameter that corresponds to the ignition pressure and that governs the penetration of the ignition flame into the internal cavities. With this arrangement at least a portion of the internal cavities is ignited with a retardation only by gas pressures that rise above the ignition pressure.
    Type: Grant
    Filed: February 17, 1984
    Date of Patent: December 9, 1986
    Assignee: Dynamit Nobel Aktiengesellschaft
    Inventors: Heinrich Brachert, Dieter Girke, Gerd Kellner
  • Patent number: 4625648
    Abstract: A propellant charge and method of manufacture thereof by which the increase in maximum gas pressure within the upper use temperature range which occurs upon firing can be influenced until eliminated. The propellant charge is manufactured by compacting a first portion of the propellant charge which corresponds to between 50-80% of the total mass of the propellant charge, and then adding the balance of the propellant charge as loose powder on top of the first portion.
    Type: Grant
    Filed: September 28, 1984
    Date of Patent: December 2, 1986
    Assignee: Rheinmetall GmbH
    Inventors: Georg Klein, Eckhard Rahnenfuehrer
  • Patent number: 4619722
    Abstract: A solid propellant acts in a chamber to propel a member such as a rocket, the chamber being closed to the atmosphere. The propellant provides high density-impulses and, when combusted, produces end products which do not have any deleterious effects. The propellant preferably includes a binder having hydrocarbon linkages and a lead compound oxidizer formed from an inorganic lead oxidizer salt. This oxidizer has dense characteristics and stable properties at ambient temperatures and through a particular range of temperatures above ambient. The propellant also includes a fuel additive, preferably a metal such as aluminum, having properties of being oxidized by the oxidizer and of reducing the lead. The fuel additive has a percentage by weight relative to the lead compound oxidizer to reduce the lead to lead oxide. The fuel additive is preferably included in the propellant in the range to approximately twenty percent (20%) by weight and is preferably in a fragmentary form.
    Type: Grant
    Filed: September 12, 1983
    Date of Patent: October 28, 1986
    Assignee: Universal Propulsion Company, Inc.
    Inventor: Frank A. Marion