Patents Assigned to Avco Everett Research Laboratory, Inc.
  • Patent number: 4259988
    Abstract: A vortex-diode check valve comprises a short cylindrical working chamber with an axial inlet port entering axially through a first end wall at a short distance from the central portion of a second end wall and a tangential outlet port exiting tangentially through a circular side wall. The ratio of fluid flow resistances, between flows in the reverse and forward directions, is markedly increased by configuring at least one end wall as a flexible resilient diaphragm, permitting relative motion between the second end wall and the axial inlet port.
    Type: Grant
    Filed: September 17, 1979
    Date of Patent: April 7, 1981
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventor: Param I. Singh
  • Patent number: 4258753
    Abstract: A fluidic amplifier or switch for supplying pulses of a power gas to be controlled which is insensitive to load impedance or back pressure. One arm of the fluidic switch comprising part of the gas injection path is coupled to a working outlet and the other arm is coupled through a sonic orifice to a vent outlet. An orifice is provided in the downstream end of the power gas injection path, the injection pressure is maintained at preferably at least about twice the maximum back pressure and a substitute gas is injected into the arm of the fluidic switch not carrying the power gas to be controlled. The two gases are each alternately supplied to the working outlet and the vent outlet. When the power gas to be controlled is supplied to the working outlet, the substitute gas is supplied to the vent outlet and when the substitute gas is supplied to the working outlet, the power gas to be controlled is supplied to the vent outlet to maintain the pressure constant across the working outlet orifice.
    Type: Grant
    Filed: May 18, 1979
    Date of Patent: March 31, 1981
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventor: Rudolf Limpaecher
  • Patent number: 4237404
    Abstract: A high repetition rate high power spark gap switch of the type useful in pulsed lasers, radar systems and pulse-forming networks is enabled to operate with higher switching speed at high power levels by rapid chemical composition change cyclically made in the spark gap at high frequency with differing standoff voltage capabilities of different compositions produced in the gap in each cycle. The different standoff voltage capabilities are produced by injecting different gases under fluidic switching control.
    Type: Grant
    Filed: May 18, 1979
    Date of Patent: December 2, 1980
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventor: Rudolf Limpaecher
  • Patent number: 4229708
    Abstract: This invention is directed towards a scalable X-ray laser comprising means for providing an active medium of lithium-like atoms or ions, means for producing in the active medium a population of low density ions in an excited intermediate metastable state and a visible or near infrared laser to stimulate X-ray lasing by resonant or non-resonant antistokes Raman process to the ground state of the ions. The irradiation of the ions by the laser provides phased or traveling wave excitation which produces the desired directivity. Production of the metastable state is provided by directing energy from a suitable source, such as a high power short pulse laser beam, onto a target material and causing it to radiate as a black body, filtering this radiation to derive radiation in the soft X-ray region, and directing this filtered radiation into the lithium-like vapor.
    Type: Grant
    Filed: April 8, 1977
    Date of Patent: October 21, 1980
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: Siva A. Mani, Howard A. Hyman, Jack D. Daugherty
  • Patent number: 4211983
    Abstract: Improved electron beam driven gas laser method and apparatus with the achievement of high single pulse energies therefore enabled by establishment of a magnetic field in a direction substantially parallel to the desired direction of electron beam propagation into a gas. The applied magnetic field is made substantially uniform and sized to exceed that of the self induced magnetic field of the current established by the electron beam, alone or in combination with a discharge current (optionally) established in the gas.
    Type: Grant
    Filed: May 1, 1978
    Date of Patent: July 8, 1980
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: Jack D. Daugherty, Jonah H. Jacob, Joseph A. Mangano
  • Patent number: 4203078
    Abstract: Apparatus for and method of operating a laser wherein a discharge is produced preferably in a high pressure lasing gaseous mixture comprising at least one suitable first gaseous species capable of providing an excited state which has a finite probability of being ionized and a molecular second gaseous species having a capability for attaching electrons to form negative ions. The gaseous mixture may, for example, comprise argon, neon, helium, xenon, krypton or a metal vapor such as mercury as the first species and, for example, hydrogen iodide, carbon tetrachloride, bromine, iodine or fluorine as the second species. A buffer gas such as, for example, argon, helium or neon may also be used. The discharge is produced by means of an electron beam and an electric field. The discharge resulting from the application of the electric field heats secondary electrons produced by the electron beam to an energy level sufficient to make excited states.
    Type: Grant
    Filed: May 6, 1977
    Date of Patent: May 13, 1980
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: Jack D. Daugherty, Jonah H. Jacob, Joseph A. Mangano
  • Patent number: 4156207
    Abstract: An electric discharge gas laser has a turbulence generator inserted in the flow path of the gas upstream of the optical cavity. The turbulence generator is illustrated as a screen. The turbulence is also disclosed as resulting from a vortex-causing blade inserted in the gas conduit. The turbulence resulting in the gas flow provides energy and specie diffusion to the outer walls at a rate relatively faster than laminar (molecular) diffusion, thereby permitting stable operations of the diffuse electric discharge at relatively higher powers.
    Type: Grant
    Filed: June 3, 1977
    Date of Patent: May 22, 1979
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventor: James P. Reilly
  • Patent number: 4151486
    Abstract: A tunable alkali metallic vapor laser system is disclosed. Stimulated Raman scattering (SRS) in a low pressure atomic alkali metallic vapor of potassium or cesium is utilized wherein the atomic vapor is provided and then primed to populate an intermediate level such as the 4P.sub.1/2 level for potassium and the 6P.sub.1/2 level for cesium from which the desired upper laser level is accessible. After the population is created at the intermediate level, it is pumped to a virtual level near the desired upper laser level by a tunable dye laser and, via the SRS process, generates the tunable output laser beam.
    Type: Grant
    Filed: March 9, 1977
    Date of Patent: April 24, 1979
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: Irving Itzkan, Robert T. V. Kung
  • Patent number: 4123798
    Abstract: This invention relates to apparatus and methods for providing a high-density memory for electrical data and more particularly, to such a memory wherein data are represented by patterns of charge written and read by electron beam means at addressed locations.
    Type: Grant
    Filed: December 5, 1977
    Date of Patent: October 31, 1978
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: Francis J. Cook, Frederick E. Kline
  • Patent number: 4092405
    Abstract: Method of and apparatus for non-equilibrium chemical kinetic separation of deuterium from hydrogen are described wherein hydrogen with its normal abundance of deuterium and an appropriate reactant, bromine, are supplied to a deuterium reaction vessel wherein they are vibrationally excited by, for example, being exposed to a volumetrically scalable ionizing-sustainer electrical discharge effective to provide vibrational excitation of the H.sub.2 and HD following which selective intermolecular vibration-vibration energy pumping occurs giving conditions effective to produce an HBr/DBr product mixture. The ionizing-sustainer discharge is effective to generate vibrational excitation from which follows chemical reactions that produce DBr and HBr at such relative rates that the mixture is enhanced in deuterium content relative to said content of the entering hydrogen stream. For the production of heavy water, the DBr and HBr are then dissolved in water.
    Type: Grant
    Filed: June 1, 1976
    Date of Patent: May 30, 1978
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: Charles W. von Rosenberg, Jr., James J. Ewing, Robert E. Center, Hao-Lin Chen
  • Patent number: 4079340
    Abstract: Herein described is an unstable resonator optical cavity for lasers which may have a square, rectangular or the like spherical concave primary reflection surface at one end of the cavity that intercepts the optical axis of the cavity at or adjacent to one of its corners and a more or less similar square, rectangular or the like spherical convex feedback reflection surface at the opposite end of the optical cavity that intercepts the optical axis at or adjacent to one of its corners arranged and adapted to define an unstable resonator cavity.
    Type: Grant
    Filed: June 21, 1976
    Date of Patent: March 14, 1978
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: Melvin M. Weiner, George W. Sutton
  • Patent number: 4065732
    Abstract: A laser comprises an optical resonant cavity construction utilizing opposing corner cube and W-fold mirrors to provide a four-pass folded optical path which is not dependent upon critical alignment between the said mirrors and therefore eliminates necessity for rigid optical bench structure therebetween.
    Type: Grant
    Filed: July 29, 1976
    Date of Patent: December 27, 1977
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventor: Frank H. Scammell
  • Patent number: 4061944
    Abstract: An electron beam window structure for broad area electron beam generators wherein a stream of electrons generated in an evacuated enclosure and extending over a broad area are passed through a thin window to a region of high pressure outside the enclosure. The structure is positioned between the metal window and the electron emission means of the electron beam generator and comprises a generally flat metal plate of high thermal conductance having closely spaced parallel slots extending over and covering the intended area of the electron beam. The bottom of each slot is disposed adjacent one surface of the plate and over its length and is provided with a row of closely spaced holes of the same diameter as the bottom width of the slot. The holes go through the remaining material leaving a small web between adjacent holes. The metal window is mounted on the slotted side of the plate while the side of the plate with the holes faces the emission means disposed in the evacuated enclosure.
    Type: Grant
    Filed: June 25, 1975
    Date of Patent: December 6, 1977
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventor: Gardiner Gay
  • Patent number: 4015100
    Abstract: Properties of a surface layer of a metal part are modified by changing its composition and microstructure using focused radiant energy. Minor components of an alloy having the metal of the substrate as the major component thereof are applied to the surface and a limited depth surface layer of the substrate metal is melted, the coated-on components are mixed therewith and the mixture is rapidly cooled to produce a desired surfacing alloy to a controlled depth within the substrate and having a fine grained microstructure compared to the microstructure of the substrate metal. The amount of coated-on minor alloy components and the preselected depth of melting of the substrate metal provide alloy composition control.
    Type: Grant
    Filed: September 8, 1975
    Date of Patent: March 29, 1977
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: Daniel S. Gnanamuthu, Edward V. Locke
  • Patent number: 4010427
    Abstract: A method and apparatus for controlling the power of a laser beam issuing from a gaseous working medium in a working region wherein the gas is subjected to an electric field and an ionizing beam is directed to the gas, ionizing the gas and producing therein secondary electrons sufficient to support laser action wherein the power of the laser beam is controlled by controlling the power of the electron beam and the electron beam power is controlled by an electrical feedback signal from a radiation detector that detects a fraction of the laser beam reflected from a plurality of reflective small wires carried by a rotatable hub which causes the wires to sequentially pass through the laser beam and reflect a small fraction of the laser beam towards the radiation detector.
    Type: Grant
    Filed: March 8, 1976
    Date of Patent: March 1, 1977
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: Diarmaid H. Douglas-Hamilton, Ethan D. Hoag
  • Patent number: 4008444
    Abstract: In a method and apparatus for producing and controlling a beam of radiation such as a laser beam issuing from a gaseous working medium in a working region wherein the gas is subjected to an electric field and an ionizing beam is directed to the gas, ionizing the gas and producing therein secondary electrons sufficient to support laser action, the power of the laser radiation is controlled by controlling the power of the electron beam and the electron beam power is controlled by an electrical feedback signal from a radiation detector that detects a fraction of the laser radiation.
    Type: Grant
    Filed: January 19, 1976
    Date of Patent: February 15, 1977
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: Jacob L. Zar, Robert E. Serris
  • Patent number: 3985123
    Abstract: A cardiac output monitor. The monitor receives signals representing radial arterial pressure, balloon pressure, balloon drive and balloon volume from an intra-aortic balloon pumping system. These signals are processed to define balloon depletion pressure (P.sub.1), ventricle ejection pressure (P.sub.2), balloon volume (BV) and heart rate (HR). The monitor displays the cardiac output according toCardiac output = (P.sub.2 /P.sub.1) (BV) (HR)the monitor also indicates certain improper pumping system operations and can provide a continuous display.
    Type: Grant
    Filed: July 17, 1975
    Date of Patent: October 12, 1976
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: George A. Herzlinger, Armando Federico, Arthur R. Kantrowitz
  • Patent number: 3982200
    Abstract: A two chamber electrically pumped electron beam stabilized gas discharge laser is enabled to operate at lower electron accelerating voltages for given power applications through provision of very thin separating diaphragms. The apparatus is controlled throughout initial pump down, laser gas filling, laser operation and air release phases to prevent occurrence of a diaphragm rupturing pressure differential between the two chambers or the inadvertent malsequencing of chamber evacuation and backfill.
    Type: Grant
    Filed: September 4, 1973
    Date of Patent: September 21, 1976
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: Ethan D. Hoag, Henry E. Pease
  • Patent number: 3982205
    Abstract: A method of producing a lasable gaseous mixture for use in and operation of electron beam-sustainer carbon dioxide lasers comprising burning a hydrocarbon fuel to produce substantially oxygen free products of combustion, removing undesirable constituents to leave a gaseous mixture which can support laser oscillation comprising substantially only carbon dioxide, nitrogen and hydrogen, collecting the resulting gaseous mixture, and thereafter supply and use it as the active medium in an electron beam-sustainer laser.
    Type: Grant
    Filed: October 17, 1974
    Date of Patent: September 21, 1976
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventors: George W. Sutton, Diarmaid H. Douglas-Hamilton
  • Patent number: RE29815
    Abstract: A metal layer is clad to a metal substrate by laying spaced rods or wires of a cladding metal on the substrate surface and scanning the cladding metal with a continuously operating laser beam, part of which impinges directly on the cladding metal to melt it and part of which impinges on the adjacent surface area of the substrate to improve flow of molten metal thereon. The cladding metal may be fed to the substrate surface in synchronism with laser beam scanning. The process produces a clad layer of the cladding metal on the substrate characterized by a fine and homogeneous structure within the clad on layer and further characterized by uniform and high hardness compared to prior art cladding methods. The surface of the clad may be smoothed by locally oscillating the laser beam during the course of cladding and/or by multiple passes.
    Type: Grant
    Filed: June 15, 1977
    Date of Patent: October 24, 1978
    Assignee: Avco Everett Research Laboratory, Inc.
    Inventor: Daniel S. Gnanamuthu