Patents by Inventor William S. Melvin

William S. Melvin 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: 5284995
    Abstract: A method to extract and recover nitramine oxidizers from solid propellant ing liquid ammonia employs four basic steps which are: (1) propellant removal by cutting or eroding into small pieces, followed by, (2) solution of the oxidizers by liquefied gas solvent ammonia, (3) separation of the insoluble binder, metal fuel, and additive components by filtration and recovery of the solid oxidizer by evaporation of the liquefied gas solvent ammonia, and (4) recompression to liquefy the gas solvent for reuse. The process is a closed system with no release of solvent to the environment. Cycle 1 reduces propellant size to 1/4 inch or less to achieve efficient extraction in cycle 2 where insoluble ingredients (binder, metal fuel, additives) are separated from soluble ingredients. Insolubles are recovered and the solubles are recovered in cycle 3 by evaporation of the liquefied gas solvent ammonia. Cycle 4 is a solvent liquefaction and recycling of the liquid ammonia to the closed system.
    Type: Grant
    Filed: March 8, 1993
    Date of Patent: February 8, 1994
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: William S. Melvin
  • Patent number: 4952254
    Abstract: A high impulse, non-detonable solid propellant grain is prepared from a cd detonable proepllant composition having a small critical diameter of less than one inch and an uncured detonable propellant composition having a large critical diameter of several inches. The method of preparation comprises grinding or cutting the cured detonable propellant composition into granules less than its critical diameter in any direction. An uncured propellant composition, in a predetermined amount of les than its critical diameter, is prepared, and the granules of the cured propellant are added and blended with the uncured propellant composition (which serves as the propellant binder) to form a homogeneous propellant blend. The homogeneous propellant blend is cured to yield a high impulse, non-detonable solid propellant grain having a critical diameter less than the critical diameter of the uncured propellant composition.
    Type: Grant
    Filed: August 7, 1989
    Date of Patent: August 28, 1990
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Robert E. Betts, Lawrence B. Thorn, William S. Melvin
  • Patent number: 4909868
    Abstract: A method to extract and recover plasticizers and their stabilizers from solid propellants, explosives, and pyrotechnics (PEP source compositions) employs near critical liquid (NCL) or supercritical fluid (SCF) CO.sub.2 as the solvent. The extraction and ingredient recovery method provides an environmentally acceptable alternative to traditional open burning and destruction of PEP source compositions. CO.sub.2 solvent is nontoxic, nonflammable, noncorrosive, inexpensive, and does not generate any additional toxic or hazardous wastes. The solvent is totally inert when it is confined, pressurized, and possibly heated in direct contact with an energetic propellant or munition within a rocket motor or similar pressure vessel. CO.sub.2 readily undergoes a gas-to-liquid phase change to NCL conditions when confined and compressed to a pressure of 831 psig or greater at ambient temperature. By further increasing the pressure and temperature of NCL CO.sub.2 to 1058 psig and 31.3.degree. C.
    Type: Grant
    Filed: October 16, 1989
    Date of Patent: March 20, 1990
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: William S. Melvin
  • Patent number: 4854982
    Abstract: Liquid ammonia is maintained at the required operating conditions to efficiently and rapidly achieve propellant demilitarization including recovery of ammonia perchlorate (AP) for reuse, by an environmentally safe method to comminute and remove propellant from existing rocket motor hardware. The method is also applicable to both solid and ground composite propellant which includes scrap or waste propellant. A disclosed demilitarization unit employed in the ammonium perchlorate recovery method is comprised of a supply and high pressure spray system for liquid ammonia, an extraction system, oxidizer recovery system, and an ammonia recovery, drying, and recycling system. The method is workable at ambient temperature since ammonia is liquified under its own vapor pressure at 114 psig; however, increased temperature further enhances the extraction efficiency of the system.
    Type: Grant
    Filed: January 31, 1989
    Date of Patent: August 8, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: William S. Melvin, James F. Graham
  • Patent number: 4649702
    Abstract: A rocket motor that has a fast burning propellant therein with a dispenser rrangement for dispensing a fluid chemical suppressant into the exhaust gases of the solid propellant for reducing the flash signature.
    Type: Grant
    Filed: August 13, 1985
    Date of Patent: March 17, 1987
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Robert E. Betts, William S. Melvin, Lawrence B. Thorn
  • Patent number: 4642983
    Abstract: A method and design are disclosed for the introduction of ammonia gas into he rocket motor gas environment wherein the ammonia gas functions to suppress the flash signature.The firing and pressurization of a sealed container having suppressant vents results in the rupturing of one or more seals for the container containing clathrate means from which adsorbed liquid or gaseus ammonia is boiled out and discharged and mixed with combustion gases prior to being discharged through the exhaust nozzle of a rocket motor.The design for the container for containing clathrate means include as part of one embodiment a toroidal shaped container for installing within the rocket motor exhaust nozzle wherein the container functions as the throat of the exhaust nozzle of the rocket motor. Other embodiments feature the clathrate means in a sealed container which additionally houses the ignitor means.
    Type: Grant
    Filed: May 6, 1985
    Date of Patent: February 17, 1987
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: William S. Melvin, Robert E. Betts, Lawrence B. Thorn
  • Patent number: H273
    Abstract: The mixing of high solids loaded propellants is accomplished under reduced viscosity conditions by employing near critical liquid (NCL) carbon dioxide as the processing fluid in a volume amount from about 10 to about 20 percent of the volume of the propellant ingredients.A typical propellant composition contains about 88 percent solids portion by weight comprised of ammonium perchlorate, aluminum powder, ballistic modifiers, and bonding agent and about 12 percent liquid portion by weight comprised of liquid polymers, plasticizers, and curatives.NCL carbon dioxide facilitates low viscosity mixing of propellant ingredients in a completely inert processing fluid. The method allows the entire mixing procedure to be conducted under reduced temperature conditions (e.g., 90.degree. F. vs 140.degree. F.), and thereby, provides for extended propellant pot life. Pressure mixing in a range of 760 psig to 1000 psig enables carbon dioxide to be maintained as a NCL to assist propellant mixing.
    Type: Grant
    Filed: December 1, 1986
    Date of Patent: May 5, 1987
    Inventors: William S. Melvin, Porter H. Mitchell
  • Patent number: H305
    Abstract: An effective method to recover the catalyst material, ferrocene or its deatives, from high burn rate propellants comprises the method which uses compressed gas in the form of a near critical liquid to extract, remove, and recover the specific catalyst material directly from rocket motors or from chunks of cut propellant.The method comprises introducing compressed carbon dioxide into a pressure vessel containing the propellant from which the catalyst material is to be recovered. The carbon dioxide as a near critical liquid (NCL) is circulated within the pressure vessel where extraction of ferrocene or its derivatives directly from the propellant takes place. The NCL with extractibles is transported to a warming and recovery zone where the extractibles are recovered after the carbon dioxide is volatilized and returned for recycling, compressing, and further extracting after being adjusted to a near critical liquid.Analytical data indicates that from 99.
    Type: Grant
    Filed: November 6, 1986
    Date of Patent: July 7, 1987
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Porter H. Mitchell, William S. Melvin
  • Patent number: RE34419
    Abstract: Liquid ammonia is maintained at the required operating conditions to efficiently and rapidly achieve propellant demilitarization including recovery of ammonia perchlorate (AP) for reuse, by an environmentally safe method to comminute and remove propellant from existing rocket motor hardware. The method is also applicable to both solid and ground composite propellant which includes scrap or waste propellant. A disclosed demilitarization unit employed in the ammonium perchlorate recovery method is comprised of a supply and high pressure spray system for liquid ammonia, an extraction system, oxidizer recovery system, and an ammonia recovery, drying,* and recycling system. The method is workable at ambient temperature since ammonia is liquified under its own vapor pressure at 114 psig; however, increased temperature further enhances the extraction efficiency of the system.
    Type: Grant
    Filed: June 25, 1990
    Date of Patent: October 26, 1993
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: William S. Melvin, James F. Graham