By Vibration Patents (Class 73/24.01)
  • Publication number: 20020178787
    Abstract: A method and apparatus for measuring properties of a liquid composition includes a mechanical resonator, such as a thickness shear mode resonator or a tuning fork resonator, connected to a measurement circuit. The measurement circuit provides a variable frequency input signal to the tuning fork, causing the mechanical resonator to oscillate. To test the properties of a liquid composition, the mechanical resonator is placed inside a sample well containing a small amount of the liquid. The input signal is then sent to the mechanical resonator and swept over a selected frequency range, preferably less than 1 MHz to prevent the liquid being tested from exhibiting gel-like characteristics and causing false readings. The mechanical resonator's response over the frequency range depends on various characteristics of the liquid being tested, such as the temperature, viscosity, and other physical properties.
    Type: Application
    Filed: July 23, 2002
    Publication date: December 5, 2002
    Applicant: Symyx Technologies, Inc.
    Inventors: Leonid Matsiev, James Bennett, Eric McFarland
  • Patent number: 6474137
    Abstract: A method and apparatus for measuring the relative density of a gas, for example natural gas. The gas is supplied through an inlet to a chamber and is output through an outlet. Using a control and an ultra-sonic transducer emitter and an ultra-sonic transducer receiver, the speed of sound in the gas corrected to standard conditions is calculated. Then, the control operates to measure the relative density RD of the gas using the formula RD=a×SoSsc+b, where SoSsc is the speed of sound in the gas corrected to standard conditions, and a and b are constants.
    Type: Grant
    Filed: February 3, 2000
    Date of Patent: November 5, 2002
    Assignee: Lattice Intellectual Property Limited
    Inventors: Paul Stephen Hammond, Robert Richard Thurston
  • Patent number: 6460402
    Abstract: A system for determining the composition of a multiple-component fluid and for determining linear flow comprising at least one sing-around circuit that determines the velocity of a signal in the multiple-component fluid and that is correlatable to a database for the multiple-component fluid. A system for determining flow uses two of the inventive circuits, one of which is set at an angle that is not perpendicular to the direction of flow.
    Type: Grant
    Filed: February 2, 2000
    Date of Patent: October 8, 2002
    Assignee: Bechtel BWTX Idaho, LLC
    Inventors: Tyler J. Gomm, Nancy C. Kraft, Larry D. Phelps, Steven C. Taylor
  • Patent number: 6442997
    Abstract: In a surface acoustic wave sensor mounted within a body, the sensor having a surface acoustic wave array detector and a micro-fabricated sample preconcentrator exposed on a surface of the body, an apparatus for collecting air for the sensor, comprising a housing operatively arranged to mount atop the body, the housing including a multi-stage channel having an inlet and an outlet, the channel having a first stage having a first height and width proximate the inlet, a second stage having a second lower height and width proximate the micro-fabricated sample preconcentrator, a third stage having a still lower third height and width proximate the surface acoustic wave array detector, and a fourth stage having a fourth height and width proximate the outlet, where the fourth height and width are substantially the same as the first height and width.
    Type: Grant
    Filed: October 1, 2001
    Date of Patent: September 3, 2002
    Assignee: Lockheed Martin Corporation
    Inventors: Clifford A. Megerle, Douglas R. Adkins, Gregory C. Frye-Mason
  • Patent number: 6442996
    Abstract: A method and apparatus for measuring the calorific value of a gas. The apparatus includes a chamber to which a gas in question, for example natural gas, is supplied through an inlet and leaves through an outlet. The speed of sound SoS at ambient temperature is measured using any suitable method such as electronic control and a calculating device and an ultra-sound emitter and an ultra-sound receiver. The ambient temperatures Ta, is observed by a temperature sensor, and a thermal conductivity sensor measures the thermal conductivity of the gas at two different temperatures above the ambient temperature. One value ThCH, of the thermal conductivity is measured at 70° C. above ambient and the other value ThCL of the thermal conductivity is measured at 50° C. above ambient. The control calculates the calorific value CV of the gas according to the formula: CV=a·ThCH+b·ThCL+C·SoS+d·Ta+e·Ta2 +f, where a, b, c, d, e and f are constants.
    Type: Grant
    Filed: August 29, 2000
    Date of Patent: September 3, 2002
    Assignee: Lattice Intellectual Property Limited
    Inventors: Robert Richard Thurston, Paul Stephen Hammond, Barry Leonard Price
  • Patent number: 6418782
    Abstract: When a sensor has deteriorated, the propagation time T1′ of a first reflection wave becomes greater than the propagation time T1 of a first reflection wave as measured in a new sensor. If measurement of the concentration of a specific gas is based on the propagation time T1 of the first reflection wave as measured in the new sensor, gas concentration cannot be determined accurately. By contrast, a reflection wave other than the first reflection wave (for example, a second reflection wave) is merely reflected off the surface of the ultrasonic element and is not affected by the internal structure of the ultrasonic element. Therefore, even when the sensor is deteriorated, the propagation time T2, T2′ of the second reflection wave exhibits less variation and is less susceptible to deterioration of the sensor.
    Type: Grant
    Filed: January 11, 2000
    Date of Patent: July 16, 2002
    Assignee: NGK Spark Plug Co., Ltd
    Inventors: Yoshikuni Sato, Noboru Ishida, Hideki Ishikawa, Takafumi Oshima, Yasushi Sato
  • Publication number: 20020062681
    Abstract: A device that measures the concentration of a particular gas within a sample of gas includes a housing having a gas flow path with a gas inlet port designed to receive the sample of gas, a gas outlet port, and a chamber extending between the gas inlet and outlet ports. The sample of gas flows into the inlet port, proceeds through the chamber and exits the housing through the outlet port. The device further includes a first ultrasonic transmitter positioned within the chamber near the inlet port capable of transmitting an ultrasonic pulse into the chamber in a direction with the flow of gas, and a second ultrasonic transmitter positioned within the chamber near the outlet port capable of transmitting an ultrasonic pulse into the chamber in a direction against the flow of gas.
    Type: Application
    Filed: November 30, 2000
    Publication date: May 30, 2002
    Inventor: Richard A. Livingston
  • Patent number: 6378372
    Abstract: An acoustic device for continuously or intermittently determining the composition of gas mixtures. The acoustic device has an acoustic resonator with input and output transducers arranged to minimize the effect of external conditions. The device normally operates as a feedback oscillator with the oscillation frequency determined by the gas-filled resonator's natural frequency, providing a speed of sound measurement. The device is configured as two open ended parallel side by side adjacent one half wavelength tubes, each with sending and receiving transducers inserted through a tube wall at the midpoint of that tube. This forms a symmetric quarter wave resonator from each tube. The two sending transducers are operated out of phase, as are the two receiving transducers. The causes cancellation of external sounds, and of their influence on measurements. A small pressure relieved cap is preferably placed over the external surface of each transducer.
    Type: Grant
    Filed: May 15, 2001
    Date of Patent: April 30, 2002
    Inventor: Lawrence J. Karr
  • Patent number: 6367329
    Abstract: A method for determining the endpoint of a plasma etch process is disclosed. The endpoint of the plasma etch process is determined using an acoustic cell attached to an exhaust port on a reaction chamber of a plasma reactor. The gas from the reaction chamber flows into the acoustic cell during the plasma etch process. Acoustic signals are periodically transmitted through the gas flowing in the acoustic cell and a first velocity for the acoustic signals associated with etching a first material layer formed on a substrate is determined. Thereafter, the endpoint of the plasma etch step is determined when the first velocity changes to a second velocity associated with etching the first material layer through its thickness to its interface with an underlying material layer. The gas from the reaction chamber flows through a compressor prior to flowing into the acoustic cell to increase the gas pressure in the acoustic cell.
    Type: Grant
    Filed: August 25, 2000
    Date of Patent: April 9, 2002
    Assignee: Agere Systems Guardian Corp.
    Inventors: Edward Alois Reitman, Gardy Cadet
  • Patent number: 6363772
    Abstract: A system and method that allows for early detection of biological conditions, such as a disease, through analysis of appropriate gaseous samples. The system and method are particularly amenable to the early screening for diseases, such as lung cancer, through the detection of specific biomarkers when present in exhaled breath from an individual. A preferred system implements a CO overtone laser that generates radiation and directs it through a photoacoustic cell. The absorption of the radiation is detected acoustically, and the absorption characteristics are utilized in determining the presence of a specific biological condition.
    Type: Grant
    Filed: December 10, 1999
    Date of Patent: April 2, 2002
    Assignee: Quadrivium, L.L.C.
    Inventor: Michael J. Berry
  • Patent number: 6357278
    Abstract: A sensor comprises a substrate and a polymeric film disposed on the substrate. The polymeric film comprises at least one hardblock component and at least one softblock component. The invention also sets forth a method for enhancing detection of a target compound by a sensor. The method comprises disposing a polymeric film on a surface of the sensor, in which the polymeric film enhances detection of target compounds not normally sensed by a sensor without the polymeric film. The polymeric film comprises at least one hardblock component and at least one softblock component.
    Type: Grant
    Filed: August 9, 1999
    Date of Patent: March 19, 2002
    Assignee: General Electric Company
    Inventors: Timothy Mark Sivavec, Radislav Alexandrovich Potyrailo
  • Publication number: 20010054305
    Abstract: An apparatus that is configured to sense the presence of gases, vapors and liquids using acoustic waves. The apparatus comprises a first part that is configured to generate acoustic waves. The apparatus further comprises a second part having a sensing and acoustic wave guiding device, which is configured to sense the presence of such substances and propagate acoustic waves. The first part is removably fixable to the second part of the apparatus. When the first part is fixed to the second part, the acoustic waves propagate in the second part.
    Type: Application
    Filed: April 6, 2001
    Publication date: December 27, 2001
    Inventors: Pedro Banda, Andrew Campitelli
  • Patent number: 6321588
    Abstract: A device for detecting chemical substances includes a plurality of sensors arranged in an array. The sensors are connected to respective oscillator circuits which drive the sensors, and the oscillator circuits are coupled to a power multiplexer which provides the circuits with power according to a timing pattern such that not all of the oscillator circuits are activated at any one time. Preferably, only one oscillator circuit is activated at any given time. This multiplexing arrangement saves power and substantially eliminates cross talk between the oscillator circuits. The oscillator circuits are preferably application specific integrated circuits (ASICs), and the sensors are preferably surface acoustic wave (SAW) devices. In use, the SAW sensors are exposed to a gas, such as air, containing the chemical substance to be detected. Signals from the SAW sensors are analyzed to identify the chemical substance.
    Type: Grant
    Filed: September 11, 1998
    Date of Patent: November 27, 2001
    Assignee: Femtometrics, Inc.
    Inventors: William D. Bowers, Frank Bahrami, John Tran
  • Patent number: 6308572
    Abstract: A gas concentration sensor comprises an ultrasonic element 33 opposite a reflection surface 34. A depression 34a is formed on an edge portion of a reflection surface 34 which is in contact with a side wall of a measurement chamber 32 such that a bottom surface of the depression 34a is substantially in parallel with the reflection surface 34. The distance between the ultrasonic element 33 and the edge portion of the reflection surface 34 becomes greater than the distance between the ultrasonic element 33 and a central portion of the reflection surface 34. As a result, an indirect wave, which impinges obliquely on the side wall of the measurement chamber 32 and propagates along the side wall, is reflected from the bottom surface of the depression 34a and propagates.
    Type: Grant
    Filed: February 15, 2000
    Date of Patent: October 30, 2001
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Hideki Ishikawa, Yoshikuni Sato, Keigo Banno, Noboru Ishida, Takafumi Oshima
  • Patent number: 6305212
    Abstract: A method and apparatus for real time gas analysis involving determining individual concentrations of fluid constituents in a mixture of known constituents by measuring properties of the mixture and solving a set of equations, which relate the individual gas concentrations to the measured properties of the mixture, for the unknown individual gas concentrations. The individual concentrations of four gasses in a mixture are determined by: passing the mixture through a flowmeter, a capillary, an orifice, and a sonic oscillator; transducing temperature, pressure and acoustic frequency measurements taken from the sensors; determining the density, viscosity, and the specific heat of the mixture; forming three equations which respectively relate these three properties to individual gas concentrations; and solving the three equations and the constitutive equation which requires that the sum of the concentrations equal unity, for the four unknown individual gas concentrations.
    Type: Grant
    Filed: April 7, 2000
    Date of Patent: October 23, 2001
    Assignee: metaSENSORS, Inc.
    Inventor: Tadeusz M. Drzewiecki
  • Patent number: 6286360
    Abstract: A gas analyzer (10) integrated into the main passageway (11) of a breathing circuit includes pressure-drop flow element (12) that measures a pressure drop across an orifice, an acoustic flowmeter (14) measures the speed of sound in the gas mixture, and a SAW device (20) from which the viscosity of the gas mixture is determined. The dielectric constant of the gas mixture is determined from the capacitance of spaced-apart charged plates of a capacitor (22) through which the mixture passes. The gas mixture density is determined from the measured pressure drop and flow rate, while the gas mixture specific heat is determined from the density and speed of sound in accordance with known relationships. The individual concentrations of five constituents of a mixture of gasses can be determined by solving five equations relating the independently measured properties of the gas mixture to the individual constituent concentrations.
    Type: Grant
    Filed: February 25, 2000
    Date of Patent: September 11, 2001
    Assignee: Metasensors, Inc.
    Inventor: Tadeusz M. Drzewiecki
  • Patent number: 6279379
    Abstract: Apparatus (15, 30) and methods for performing acoustical measurements are provided having some and preferably all of the following features: (A) the system (15, 30) is operated under near-field conditions; (B) the piezoelement (40) or piezoelements (40, 48) used in the system are (i) mechanically (41, 49) and electrically (13, 16) damped and (ii) efficiently electrically coupled to the signal processing components of the system; (C) each piezoelement (40, 48) used in the system includes an acoustical transformer (42, 50) for coupling the element to a gaseous test medium (9); (D) speed of sound is determined from the time difference between two detections of an acoustical pulse (81, 82) at a receiver (40, FIG. 3; 48, FIG.
    Type: Grant
    Filed: November 19, 1999
    Date of Patent: August 28, 2001
    Assignee: Lorex Industries, Inc.
    Inventors: Raymond C. Logue, Don N. Sirota, Patrick S. Lee
  • Patent number: 6279378
    Abstract: An ultrasonic gas analyzer includes an acoustic cavity through which an air sample is drawn by a low speed air pump or other mechanism. The cavity has a pair of ultrasonic wave transmitters/receivers on opposite sides of the acoustic cavity. An electronic circuit controls the transmitters/receivers so that a high frequency ultrasonic wave is propagated across the cavity and thereby through the gas flowing through the cavity. This ultrasonic wave reflects back and forward across the acoustic cavity and the transmitters/receivers receive this wave and supply a signal indicative of the wave to an electronic circuit. Based on the time of flight data for the ultrasonic wave being reflected in a gas/air mixture and in air and the amplitude of those reflected ultrasonic waves, a determination is made as to the gases within the gas/air mixture. This determination then can be displayed and an audio signal can be generated depending on the amount of detected gases.
    Type: Grant
    Filed: October 27, 1999
    Date of Patent: August 28, 2001
    Assignee: The University of Chicago
    Inventors: Shuh-Haw Sheen, Hual-Te Chien, Apostolos C. Raptis
  • Patent number: 6266996
    Abstract: A method and device for determining concentration and rate of change of concentration of a gas having ability to act as crystal etchant, such as hydrofluoric acid (HF) or deuterium fluoric acid (DF) gas. A crystal 22 is placed in a chamber and subjected to erosion by the gas. The crystal resonant frequency, changeable during the crystal erosion, is determined and a crystal resonant frequency change is calculated to determine the concentration of the gas. The crystal 22 is preferably an AT-cut quartz crystal. The step of obtaining the crystal resonant frequency is preferably performed in a Colpitts oscillator. The step of calculating the gas concentration, proportional to the change in the crystal resonant frequency, may also encompass calculating a change and rate of change in the gas concentration, and averaging the calculated gas concentration. The crystal 22 is preferably inserted in a crystal holder 20, and mounted on an electronic box 34 which holds the oscillator board.
    Type: Grant
    Filed: October 6, 1998
    Date of Patent: July 31, 2001
    Assignee: TRW Inc.
    Inventor: Peter M. Livingston
  • Patent number: 6257048
    Abstract: A method and apparatus for measuring surface changes, such as mass uptake at various pressures, in a thin-film material, in particular porous membranes, using multiple differently-configured acoustic sensors.
    Type: Grant
    Filed: June 18, 1999
    Date of Patent: July 10, 2001
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Susan Leslie Hietala, Vincent Mark Hietala, Chris Phillip Tigges
  • Patent number: 6202468
    Abstract: The present invention relates to a method of determining the relative proportions of gases in a mixture, such that the relative proportions of N gases are determined using N-1 sensors, not all of which are specific to a particular gas. In the preferred embodiment, oxygen and carbon dioxide are measured in the presence of nitrogen by measuring magnetic susceptibility and speed of sound. The described method of gas analysis leads to very fast response times and exceptional stability, making the technology suitable for breath-by-breath analysis of respired air. Notably, the method does not require high-temperature components, electrochemical cells, or consumable components.
    Type: Grant
    Filed: January 13, 1999
    Date of Patent: March 20, 2001
    Assignee: Life Measurement Instruments
    Inventors: Philip Dempster, John Payne
  • Patent number: 6202470
    Abstract: A system and method are set forth for photoacoustical analysis of isotope and other compounds having telltale absorption wavelengths between 1700-2500 nm. The system and method includes a Co:Mg F2, an optical parametric oscillator (OPO), or a diode laser tunable between 1700-2500 nm which is directed into a sample at energies sufficient to generate detectable acoustical emissions. A microphone detects the emissions for processing and analysis. The system and method is adapted to detect stable isotope compounds such as 13CO2 as well as other chemical compounds. For non-gaseous compounds, a CO2 or diode laser is used to photoablate the gaseous sample containing the suspected compound.
    Type: Grant
    Filed: August 31, 1999
    Date of Patent: March 20, 2001
    Assignee: TRW Inc.
    Inventor: Mau-Song Chou
  • Patent number: 6192739
    Abstract: Apparatus and methods for performing acoustical measurements are provided having some and preferably all of the following features: (1) the system is operated under near-field conditions; (2) the piezoelement or piezoelements used in the system are (a) mechanically and electrically damped and (b) efficiently electrically coupled to the signal processing components of the system; (3) each piezoelement used in the system includes an acoustical transformer for coupling the element to a gaseous test medium; (4) speed of sound is determined from the time difference between two detections of an acoustical pulse at a receiver; (5) cross-correlation techniques are employed to detect the acoustical pulse at the receiver; (6) fast Fourier transform techniques are used to implement the cross-correlation techniques; and (7) stray path signals through the body of the acoustic sensor are removed from detected signals prior to signal analysis.
    Type: Grant
    Filed: November 19, 1999
    Date of Patent: February 27, 2001
    Assignee: Lorex Industries, Inc.
    Inventors: Raymond C. Logue, Don N. Sirota, Patrick S. Lee
  • Patent number: 6171867
    Abstract: The invention relates to a sensor comprising a piezoelectric crystal with a polyarylene thioether-containing coating, the coating containing at least one polyarylene system having repeating units of the formula I, —[(Ar1)n—X]m—[(Ar2)i—Y]j—[(Ar3)k—Z]l—[(Ar4)o—W]p—  (I) which contain at least one thioether group, in which Ar1, Ar2, Ar3 and Ar4 are identical or different aryl systems having from 6 to 18 carbon atoms, W, X, Y and Z are identical or different linking groups, selected from the group comprising —SO2—, —S—, —SO—, —O—, —CO—, —CO2—, alkylene or alkylidene having from 1 to 6 carbon atoms and —NR1—, where R1 is an alkyl or alkylide group having from 1 to 6 carbon atoms and at least one linking group must be —S—, n, m, i, j, k, l, o, p are, equal or different, integers zero, 1, 2, 3 or 4, their sum havin
    Type: Grant
    Filed: January 26, 1995
    Date of Patent: January 9, 2001
    Assignee: Ticona GmbH
    Inventors: Gernot Feucht, Andreas Schleicher, Georg Frank
  • Patent number: 6167747
    Abstract: A vapor recovery system is disclosed that utilizes a crystal oscillator for sensing the presence of hydrocarbon in the vapor emissions emanating from a fuel tank during refueling. The crystal oscillator is coated with a layer of material having a sensitivity for hydrocarbon. In response to any interaction between the coating layer and hydrocarbon, the crystal oscillator experiences a shift in its oscillation frequency relative to the fundamental resonance frequency. The frequency shift is representative of the hydrocarbon concentration in the vapor emissions. A control signal based on the frequency shift is generated and then used to adjust the operating speed of the vapor pump.
    Type: Grant
    Filed: August 14, 1998
    Date of Patent: January 2, 2001
    Assignee: Tokheim Corporation
    Inventors: Wolfgang H. Koch, Arthur R. Brown
  • Patent number: 6167748
    Abstract: An improved multi-element apparatus for detecting the presence of at least one chemical, biological or physical component in a monitored area comprising an array or single set of the following elements: a capacitive transducer having at least one cantilever spring element secured thereto, the cantilever element having an area thereof coated with a chemical having an affinity for the component to be detected; a pick-up plate positioned adjacent to the cantilever element at a distance such that a capacitance between the cantilever element and the pick-up plate changes as the distance between the cantilever element and the pick-up plate varies, the change in capacitance being a measurable variation; a detection means for measuring the measurable variation in the capacitance between the cantilever element and the pick-up plate that forms a measurement channel signal; and at least one feedback cantilever spring element positioned apart from the coated cantilever element, the cantilever element substantially unaffe
    Type: Grant
    Filed: August 31, 1998
    Date of Patent: January 2, 2001
    Assignees: Lockheed Martin Energy Research Corporation, University of Tennessee Research Corporation
    Inventors: Charles L. Britton, Jr., Robert J. Warmack, William L. Bryan, Robert L. Jones, Patrick Ian Oden, Thomas Thundat