Having Conductance Probe Structure Patents (Class 324/446)
  • Patent number: 6653842
    Abstract: A galvanic probe comprises a sensor electrode and a reference electrode. The sensor electrode has an exposed surface that comprises a noble metal or antimony or bismuth, and, optionally, an oxide or hydroxide thereof. The reference electrode is spaced apart from the sensor electrode and has an exposed surface that comprises zinc or magnesium, and, optionally, an oxide or hydroxide thereof. The probe may be incorporated into a device for controlling the pH and/or ORP of a fluid in a vessel to a desired pH and/or ORP level, incorporated into methods for measuring the pH and/or ORP of a fluid, or used as a galvanic cell.
    Type: Grant
    Filed: July 10, 2001
    Date of Patent: November 25, 2003
    Assignee: Digital Concepts of Missouri
    Inventors: Michael David Mosley, Paul Decker, Thomas Lee Martzall
  • Patent number: 6650121
    Abstract: A sensor for the monitoring of an NOx catalyst having a storage material for the adsorption of NOx, the storage material forming the sensitive element of the sensor. As a result, it is possible to measure the instantaneous degree of charging of the storage material, and a quasi-linear control for the storage of NOx is made possible. The ability to precisely monitor the degree of charging of the storage material makes it possible to better utilize the storage capacity, and the catalyst can be dimensioned in a more cost-effective manner. The conversion phase of the rich side can be predicted more precisely and consequently be integrated more favorably into the driving cycle. The sensor for the monitoring of an NOx catalyst is especially suitable for installation in the exhaust path of an internal combustion engine with direct gasoline injection or of a diesel engine.
    Type: Grant
    Filed: September 6, 2002
    Date of Patent: November 18, 2003
    Assignee: Robert Bosch GmbH
    Inventors: Dieter Seipler, Bernd Schumann
  • Patent number: 6593747
    Abstract: The present invention is directed to a method and apparatus of determining the degree of saturation of a decontamination-removing substance or adsorbent such as an alumina absorbent or activated charcoal. The method and apparatus is sufficiently sensitive to detect changes in the bulk specific electrical conductivity of the adsorbent.
    Type: Grant
    Filed: October 5, 1998
    Date of Patent: July 15, 2003
    Assignees: The University of Western Ontario, Bayer, Inc.
    Inventors: Judit E. Puskas, Shahzad Barghi
  • Publication number: 20030112012
    Abstract: A galvanic probe comprises a sensor electrode and a reference electrode. The sensor electrode has an exposed surface that comprises a noble metal or antimony or bismuth, and, optionally, an oxide or hydroxide thereof. The reference electrode is spaced apart from the sensor electrode and has an exposed surface that comprises zinc or magnesium, and, optionally, an oxide or hydroxide thereof. The probe may be incorporated into a device for controlling the pH and/or ORP of a fluid in a vessel to a desired pH and/or ORP level, incorporated into methods for measuring the pH and/or ORP of a fluid, or used as a galvanic cell.
    Type: Application
    Filed: July 10, 2001
    Publication date: June 19, 2003
    Applicant: Digital Concepts of Missouri, Inc.
    Inventors: Michael David Mosley, Paul Decker, Thomas Lee Martzall
  • Patent number: 6577145
    Abstract: A unit has inspection block blocks mounted thereon in parallel, wherein a plurality of inspection probe blocks are inserted into and removed from a guide rail through a slider so that the probe blocks can be loaded or replaced. Each probe block is slidingly moved along the guide rail so that its positional adjustment can be made in an extension length of the guide rail. Only one kind of support base can commonly be used by inserting and removing different probe blocks with respect to the support base and the positional adjustment can be done. The unit with inspection probe blocks mounted thereon in parallel includes a support base and a plurality of inspection probe blocks each having a plurality of blocks and arranged on the support base in parallel.
    Type: Grant
    Filed: November 7, 2001
    Date of Patent: June 10, 2003
    Assignees: Soshotech Co., Ltd., Adtec Engineering Co., Ltd.
    Inventors: Toshio Okuno, Masatomo Nagashima, Atsushi Oguma, Tadashi Furumi
  • Publication number: 20030057952
    Abstract: The invention relates to a measuring device, especially for measuring the pH value in food, comprising an extended first electrode (2) for plunging into a good to be measured (40) and a sheath (4) which at least partially surrounds said first electrode (2). The first electrode (2) is pivotally mounted in order to prevent breakage as a result of transversal loads exerted perpendicularly to the axial direction of said first electrode (2).
    Type: Application
    Filed: October 21, 2002
    Publication date: March 27, 2003
    Inventor: Andreas Derr
  • Publication number: 20030011374
    Abstract: A sensor for the monitoring of an NOx catalyst having a storage material for the adsorption of NOx, the storage material forming the sensitive element of the sensor. As a result, it is possible to measure the instantaneous degree of charging of the storage material, and a quasi-linear control for the storage of NOx is made possible. The ability to precisely monitor the degree of charging of the storage material makes it possible to better utilize the storage capacity, and the catalyst can be dimensioned in a more cost-effective manner. The conversion phase of the rich side can be predicted more precisely and consequently be integrated more favorably into the driving cycle. The sensor for the monitoring of an NOx catalyst is especially suitable for installation in the exhaust path of an internal combustion engine with direct gasoline injection or of a diesel engine.
    Type: Application
    Filed: September 6, 2002
    Publication date: January 16, 2003
    Inventors: Dieter Seipler, Bernd Schumann
  • Patent number: 6501286
    Abstract: An electrode array device for use with a conductive element to simulate a crevice that is subject to corrosive conditions. The device includes a non-conductive member and a plurality of electrodes. The non-conductive member has a face, with the member defining (i) an opening through the member, the opening passing through the face of the member, and (ii) a depression formed in the face and contiguous with at least a portion of the opening. The plurality of electrodes is embedded in the member, with each of the plurality of electrodes having a portion exposed from the member to the depression.
    Type: Grant
    Filed: August 27, 2001
    Date of Patent: December 31, 2002
    Assignee: S. C. Johnson & Son, Inc.
    Inventors: Robert W. Balfanz, James E. Buhler, W. Stephen Tait
  • Patent number: 6478948
    Abstract: A method for monitoring and reducing corrosion in furnace boiler tubes measures electrochemical noise associated with corrosion mechanisms while corrosion is occurring at the surface of the tubes as they are exposed to combustion products. This noise is detected using a probe at the boiler waterwall surface that is connected to a corrosion monitor. The monitor contains a computer and software which determines a corrosion rate from the measured electrochemical noise. That rate is compared to a standard to determine if the rate is within acceptable limits. If not, the operator of the furnace or an Adaptive Process Controller (APC) is notified and adjusts one or more burners to change the combustion products that are responsible for the corrosion. Such an adjustment could be made by changing the amount of air or fuel being provided to the burner or other air slots or air ports.
    Type: Grant
    Filed: February 26, 2001
    Date of Patent: November 12, 2002
    Assignee: ESA Corrosion Solutions, Ltd.
    Inventors: Bernard P. Breen, Dennis Tobias, David Eden, James E. Gabrielson, Ralph W. McConnell
  • Publication number: 20020125889
    Abstract: An apparatus for detecting a reduction of a level of electrolyte in a wet cell battery includes an electrically conductive sensing rod in contact with an electrolyte in a battery cell, a voltage comparator connected to the rod for generating a first output signal when an input voltage is greater than a reference voltage and generating a second output signal when an input voltage is less than the reference voltage, and an indicator responsive to the output signals for generating a green visual signal when the rod is immersed in the electrolyte and generating a red visual signal when the rod is not immersed in the electrolyte. The apparatus also include an audio alarm device sounding an audio indication when the red visual signal is generated. A sensing circuit can be connected between the voltage comparator and a pair of battery voltage input terminals to selectively connect the terminals to the comparator when a voltage of a battery connected to the terminals exceeds a predetermined voltage level.
    Type: Application
    Filed: March 5, 2002
    Publication date: September 12, 2002
    Inventor: Norton W. Whitchurch
  • Publication number: 20020101244
    Abstract: The invention relates to a measuring probe for determining the physical stability of emulsions and dispersions, constructed from a rod comprising a material which is electrically nonconductive at least on the rod surface, which carries at least two conductivity-measurement electrodes separated from one another along the rod, these electrodes being separately supplied with electricity via the interior of the rod at one rod end. The invention furthermore relates to a method for determining the physical stability of emulsions and suspensions, characterized in that an emulsion or dispersion is placed in a sample container, a measuring probe according to Claim 1 is immersed in the filled sample container, and the conductivity of the emulsion or dispersion is measured continuously or at intervals over a given period of time using the conductivity-measurement electrodes.
    Type: Application
    Filed: January 30, 2001
    Publication date: August 1, 2002
    Inventor: Gerd Dahms
  • Patent number: 6400159
    Abstract: An orientation sensor especially suitable for use in an underground device is disclosed herein. This orientation sensor includes a sensor housing defining a closed internal chamber, an arrangement of electrically conductive members in a predetermined positional relationship to one another within the chamber and a flowable material contained within the housing chamber and through which electrical connections between the electrically conductive members are made such that a comparison between an electrical property, specifically voltage, of a first combination of conductive members to the corresponding electrical property of a second combination of conductive members can be used to determine a particular orientation parameter, specifically pitch or roll of the sensor.
    Type: Grant
    Filed: April 11, 2000
    Date of Patent: June 4, 2002
    Assignee: Digital Control Incorporated
    Inventors: Rudolf Zeller, John E. Mercer
  • Patent number: 6380746
    Abstract: A plug for insertion through the wall of a vessel filled with fluid to be monitored has an extension immersed in the fluid which has a pair of wire electrodes helically wound thereon in spaced arrangement. The electrodes are wound at a uniform pitch in one embodiment and wound with regions of closely and widely spaced pitches in another embodiment. In a third embodiment, the electrodes are helically wound in spaced parallel arrangement at a pitch greater than the spacing of the pair. A thermistor is disposed on the extension for providing a fluid temperature signal. The electrodes are excited sequentially by a low voltage at a fractional Hertz (low) frequency and a (high) frequency of at least one Hertz and the current and temperature are measured. The impedance and differential impedance are computed from the measured currents.
    Type: Grant
    Filed: November 3, 1999
    Date of Patent: April 30, 2002
    Assignee: Eaton Corporation
    Inventors: Mark H. Polczynski, Paul G. Rops, Robert A. Bauer, Martin A. Seitz, Richard W. Hirthe
  • Patent number: 6377052
    Abstract: A method for real time monitoring fluid in a vessel with a probe having a pair of electrodes immersed in the fluid. The disclosed probe has the electrodes arranged helically on a rod, sized and configured for insertion in an engine dipstick hole. Preferably, the probe has spiral electrode winding up regions different pitch to provide improved impedance response at low fractional Hertz and high (at least one Hertz) frequencies of excitation. In one version with alternating voltage the difference in current magnitude measured at the low and high frequencies is compared with stored known values for known fluid conditions and an electrical signal indicative of fluid condition is generated. Examples with engine drain oil and heavy duty transmission lubricant fluid are presented. The impedance properties measured can determine the percentage remaining useful life (RUL) of the fluid.
    Type: Grant
    Filed: November 3, 1999
    Date of Patent: April 23, 2002
    Assignee: Eaton Corporation
    Inventors: Peter J. McGinnis, Paul G. Rops, Mark H. Polczynski, Francis C. Edrozo, Richard W. Hirthe, Steven R. Schachameyer, Lian Q. Zou
  • Patent number: 6370213
    Abstract: An ECP sensor includes a tubular ceramic probe having a closed tip at one end packed with a metal and metal oxide powder. A metal support tube receives an opposite end of the probe, and is joined thereto by a braze joint therewith. An electrical conductor extends through the support tube and probe, and has an end buried in the powder for electrical contact therewith. A ceramic band bridges the probe and tube at the joint for sealing thereof.
    Type: Grant
    Filed: September 17, 1999
    Date of Patent: April 9, 2002
    Assignee: General Electric Company
    Inventors: Young Jin Kim, Eric Moran, Donald Allan Hale
  • Patent number: 6278756
    Abstract: The invention relates to a sensor for a measuring an electrochemical corrosion potential comprising a sensor tip, a conductor electrically connected to the sensor tip, an insulating member which surrounds the conductor, a connecting member which surrounds the conductor; and a sleeve which fits over the sensor tip, the insulating member, and the connecting member, the sleeve having inner threads which engage with corresponding outer threads on at least one of the sensor tip and the connecting member.
    Type: Grant
    Filed: November 6, 2000
    Date of Patent: August 21, 2001
    Assignee: General Electric Company
    Inventor: Young JinKim
  • Patent number: 6277629
    Abstract: An apparatus (1) for measuring physiological parameters has a test chamber (2) having boundaries defined by a first semiconductor chip (3) and a second semiconductor chip (4), between which chips a seal (7) bordering the test chamber (2) is arranged as a distance spacer. The first semiconductor chip (3) has an active side, which faces the test chamber (2) and has planar sensors, on which biological cells (6) located in a nutrient medium can be adherently deposited in order to measure physiological parameters directly on the cells (6). The second semiconductor chip (4) has on an active side, facing the test chamber (2), at least one additional sensor to measure global physiological parameters. The semiconductor chips (3, 4) are held in the sealing position using a mounting (8) that grasps over them on the outer side. Outside of the test chamber (2) the semiconductor chips (3, 4) each have electric connection contacts, which contact with opposing contacts of the mounting.
    Type: Grant
    Filed: June 1, 2000
    Date of Patent: August 21, 2001
    Assignee: Micronas GmbH
    Inventors: Bernhard Wolf, Ulrich Sieben
  • Patent number: 6259242
    Abstract: Apparatus for sensing and characterizing particles suspended in a liquid medium includes a particle-sensing structure having a continuous wall defining a hydrodynamically smooth conduit through which the liquid suspension of particles is caused to pass simultaneously with an electrical current. Particles passing through the conduit are sensed and characterized by monitoring changes in the electrical current through the conduit. According to the invention, the continuous, conduit-defining wall is made entirely of a material having an electrical resistivity less than or equal to that of the liquid medium. Thus, the apparatus of the invention is similar to the conventional Coulter aperture (conduit) except that the aperture is formed from an electrically conductive material instead of a dielectric material.
    Type: Grant
    Filed: May 26, 1999
    Date of Patent: July 10, 2001
    Assignee: Coulter International Corp.
    Inventors: Marshall D. Graham, Harvey J. Dunstan
  • Patent number: 6181760
    Abstract: The invention relates to a sensor for a measuring an electrochemical corrosion potential comprising a sensor tip, a conductor electrically connected to the sensor tip, an insulating member which surrounds the conductor, a connecting member which surrounds the conductor; and a sleeve which fits over the sensor tip, the insulating member, and the connecting member, the sleeve having inner threads which engage with corresponding outer threads on at least one of the sensor tip and the connecting member.
    Type: Grant
    Filed: July 20, 1999
    Date of Patent: January 30, 2001
    Assignee: General Electric Company
    Inventor: Young JinKim
  • Patent number: 6175227
    Abstract: A Coulter apparatus comprises a volumeter assembly containing a conduit through which a particle suspension is caused to pass simultaneously with an electrical current. In preferred embodiments the volumeter assembly comprises at least one traditional Coulter conduit wafer, i.e., a dielectric wafer containing a central circular conduit, and at least two electrically conductive collars. The conductive collars approximate the conduit diameter in thickness, are uninsulated, and are attached to opposite sides of the conduit wafer, the openings being congruent with the Coulter conduit. The Coulter conduit in the dielectric wafer and the openings in the conductive collars collectively form a hydrodynamically smooth conduit, in which the electric and hydrodynamic fields of the Coulter conduit are amended. The electric field is shaped to confine the particle-sensitive zone of the novel volumeter conduit within the conduit's physical boundaries, thereby decreasing the zone's coincidence volume.
    Type: Grant
    Filed: July 1, 1998
    Date of Patent: January 16, 2001
    Assignee: Coulter International Corp.
    Inventors: Marshall D. Graham, Harvey J. Dunstan, Gerry Graham, Ted Britton, John Geoffrey Harfield, James S. King
  • Patent number: 6058934
    Abstract: A conductivity sensor for measuring hematocrit and a sensor housing for a blood analysis instrument using the conductivity sensor are described. The conductivity sensor includes a seven-electrode conductivity measurement cell in which three symmetric pairs of electrodes are arranged on opposite sides of a central electrode. The central electrode is connected to an AC source and the outermost pair of electrodes, which provide a return path for the current, are maintained at a ground or reference potential. The two inner pairs of electrodes measure the voltage drop along the current flow path. This arrangement confines the measurement current and potential within the sensor chamber, thereby preventing the sensor from interfering with other electrochemical sensors that may be provided in the blood analysis instrument. The sensor housing provides a linear arrangement of flow cells defining a fluid flow path through the housing.
    Type: Grant
    Filed: October 29, 1996
    Date of Patent: May 9, 2000
    Assignee: Chiron Diagnostics Corporation
    Inventor: Kevin J. Sullivan
  • Patent number: 6051422
    Abstract: The invention relates to an apparatus and method for monitoring cells and to a method for monitoring changes in cells upon addition of an analyte to the cell's environment, comprising a device which includes an array of microelectrodes disposed in a cell culture chamber, upon which array a portion of cells adhere to the surfaces of the microelectrodes. The diameter of the cells are larger than the diameters of the microelectrodes. A voltage signal is applied across each of the microelectrodes and a reference electrode. Detection and monitoring of the signals resulting from the application of the voltage signal provides information regarding the electrical characteristics of the individual cells, including impedance (combined cell membrane capacitance and conductance), action potential parameters, cell membrane capacitance, cell membrane conductance, and cell/substrate seal resistance. Such an invention is useful in detecting or screening a variety of biological and chemical agents.
    Type: Grant
    Filed: July 9, 1998
    Date of Patent: April 18, 2000
    Assignee: Board of Trustees, Leland Stanford, Jr., University
    Inventors: Gregory T. A. Kovacs, David A. Borkholder
  • Patent number: 5933016
    Abstract: A method and apparatus are disclosed for the analysis of a fluid to determine the remaining useful life of the fluid and whether the fluid has become contaminated. The method can be performed either on-line or off-line, however, the on-line method is preferred. In the method, a sample of the fluid is contacted by a single electrode which is connected to the ground potential by means of the equipment in which the fluid is used. A current is applied to the sample through the electrode and the conductivity of the sample is measured. The conductivity measurement can then compared to known values for the fluid to determine the remaining useful life of the fluid and whether the fluid has become contaminated.
    Type: Grant
    Filed: August 30, 1996
    Date of Patent: August 3, 1999
    Assignee: The University of Dayton
    Inventors: Robert E. Kauffman, James D. Wolf
  • Patent number: 5896432
    Abstract: An electrochemical corrosion potential sensor is fabricated by initially joining an electrical conductor to a sensor tip. An electrical cable is joined to the tip conductor. Ceramic powder is fused under heat around the tip conductor to form an integral annular electrically insulating band therearound to insulate the tip from the cable. The band may be formed by plasma spraying, or it may be molded and sintered to seal it to the tip and conductor without brazing. In a preferred embodiment, the band is formed of yttria-stabilized-zirconia or magnesia-stabilized-zirconia.
    Type: Grant
    Filed: September 12, 1997
    Date of Patent: April 20, 1999
    Assignee: General Electric Company
    Inventors: Young Jin Kim, Samson Hettiarachchi, Minyoung Lee, Svante Prochazka
  • Patent number: 5882598
    Abstract: A conductivity cell for use in determining ionic concentrations in the gap between two semiconductor substrates or wafers. The wafer gap conductivity cell is composed of two flat electrodes separated by a fixed gap. The electrodes are fabricated from wafers of the same type and dimensions used as semiconductor device substrates. All or a portion of the surfaces of the wafer electrodes are coated with a conductive material. The wafer gap conductivity cell is placed in a wafer cassette or other suitable wafer holder, whose other slots are filled with wafers which are to be cleaned or subjected to another fabrication process. The cell can be used to characterize the processes used during the fabrication of semiconductor devices and assist in investigating the effect on the processes of different process vessel designs.
    Type: Grant
    Filed: June 7, 1996
    Date of Patent: March 16, 1999
    Assignee: SCP Global Technologies
    Inventors: Paul George Lindquist, Robert Newell Walters
  • Patent number: 5872454
    Abstract: Disclosed is a two-point calibration procedure, that when used with a mathematical algorithm, improves the accuracy of electrolytic conductivity measurements by correcting for non-linear behavior of conductivity cells. Unlike purely mathematical means of correcting for non-linearity which may use second or higher order equations, this algorithm has the following advantages: it is based on an analysis of the physical phenomena which are responsible for non-linearity; it yields one unique solution, i.e., it uses an equation that has only one root; and it yields diagnostic information concerning the behavior of the cell.
    Type: Grant
    Filed: October 24, 1997
    Date of Patent: February 16, 1999
    Assignee: Orion Research, Inc.
    Inventor: Steven J. West
  • Patent number: 5824494
    Abstract: A method for determining the number of microorganisms in a liquid sample, including the steps of dividing the liquid sample into a plurality of separate sub-samples, measuring the magnitude of at least one impedance component across each of the sub-samples and determining the number of the sub-samples for which the measured magnitude of the at least one impedance component indicates microorganism growth. The method preferably further includes the steps of applying A.C. voltage at a plurality of frequencies across at least a portion of the sample and measuring the at least one impedance component in response to at least some of the plurality of A.C. frequencies.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: October 20, 1998
    Assignee: Sirotech Ltd.
    Inventor: Simon Feldberg
  • Patent number: 5757197
    Abstract: Sensing apparatus is disclosed which allows for the determination of the presence, absence or percentage of a conducting medium such as water, by electronic means. The inventive apparatus negates the effect of a false signal generated by contamination of the sensing apparatus. The inventive sensor comprises three or more sensing members attached to a non-conducting substrate with electronically significant distances between pairs of sensing members. An appropriate electrical circuit is connected to the sensing members which converts signals output from the pairs of sensing members into readings which indicate the presence or absence of a conducting medium, notwithstanding the presence or absence of contamination between the sensing members.
    Type: Grant
    Filed: February 2, 1996
    Date of Patent: May 26, 1998
    Inventor: John R. O'Neill
  • Patent number: 5723979
    Abstract: A sensor for use with time domain reflectometry systems to allow measurement of relative proportions of intermixed constituents having differing electrical permittivities contained in a fluid mixture. The sensor comprises a central primary electrode and a pair of adjacent outer secondary outer electrodes. The fluid mixture is located between the electrodes during sensing. A dielectric layer covers exposed sensing surfaces of the electrodes to electrically isolate the electrodes from the fluid mixture and to prevent dissipation of a time domain reflectometry signal propagated through the sensor.
    Type: Grant
    Filed: July 8, 1996
    Date of Patent: March 3, 1998
    Inventor: Charles L. Mohr
  • Patent number: 5643536
    Abstract: A method for metering a reagent into a flowing medium includes adjusting a quantity of a reagent to be metered per unit of time into a flowing medium as a function of a thickness of a reaction zone in a catalytically active material. An apparatus for metering a reagent into a flowing medium includes a control unit, a device associated with the control unit for detecting a thickness of a reaction zone, and a metering device associated with the control unit for introducing a reagent into a flowing medium upstream of a catalytic converter as seen in flow direction of the medium. The control unit adjusts a quantity of the reagent to be metered into the flowing medium per unit of time by the metering device, as a function of a thickness of the reaction zone.
    Type: Grant
    Filed: November 4, 1994
    Date of Patent: July 1, 1997
    Assignee: Siemens Aktiengesellschaft
    Inventor: Helmut Schmelz
  • Patent number: 5596266
    Abstract: A metal particle detecting sensor (10), having a simple structure, can perform in-line analysis for metal particles in fluid and also can precisely estimate or detect the number of metal particles for each particle size. Metal films (1) and insulating films (2) are alternately laminated one upon another, and every other metal film (1) in the laminate is connected in parallel with one another to one of two lead wires (3a, 3b) so as to form comb electrodes in the laminate of the sensor, and one end face of the laminate is immersed in a fluid (4) containing metal particles so as to detect the metal particles.
    Type: Grant
    Filed: June 23, 1994
    Date of Patent: January 21, 1997
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Akira Mori, Ikuo Uchino, Atsuhiko Hirosawa, Kunihiro Yamazaki
  • Patent number: 5554936
    Abstract: A sensor for use with time domain reflectometry systems to allow measurement of relative proportions of intermixed constituents having differing electrical permittivities contained in a fluid mixture. The sensor comprises a central primary electrode and a pair of adjacent outer secondary outer electrodes. The fluid mixture is located between the electrodes during sensing. A dielectric layer covers exposed sensing surfaces of the electrodes to electrically isolate the electrodes from the fluid mixture and to prevent dissipation of a time domain reflectometry signal propagated through the sensor.
    Type: Grant
    Filed: December 1, 1994
    Date of Patent: September 10, 1996
    Inventor: Charles L. Mohr
  • Patent number: 5546004
    Abstract: A sensor determines a course of concentration of an adsorbent substance, such as ammonia NH.sub.3, diffusing out of a flow medium through a surface of a sensor material into the sensor material, as a function of a distance from the surface. Individual pairs of contacts are connected to supply leads and are disposed in the sensor material and optionally on the surface of the sensor material, for determining electrical conductivity of the sensor material between the contacts of the individual pairs of contacts.
    Type: Grant
    Filed: November 4, 1994
    Date of Patent: August 13, 1996
    Assignee: Siemens Aktiengesellschaft
    Inventor: Helmut Schmelz
  • Patent number: 5543717
    Abstract: A conductivity measuring device for measuring the electric conductivity of iquids has a current source device with current electrodes connectable thereto, via which a current can be fed into the liquid, and a measuring circuit connected to two voltage electrodes.In order to reduce measuring errors on account of polarization effects, the current source device in accordance with the invention, generates the current having the rectangular waveform, wherein the measuring circuit is implemented as switched capacitor circuit comprising a measuring capacitor being connectable to and disconnectable from the voltage electrodes via a switch arrangement in time dependency of the path of the current having the rectangular waveform.
    Type: Grant
    Filed: September 21, 1993
    Date of Patent: August 6, 1996
    Assignee: Fraunhofer-Gesellschaft zur Forderung der Angewandten Forshung e.v.
    Inventor: Norbert Kordas
  • Patent number: 5537043
    Abstract: A method for monitoring cracks in a sample of materials by applying the theory that the phase angle increases in the sample of materials being tested where cracks have formed. The method is performed by preparing a solution capable of forming cracks in the sample, preparing an auxiliary electrode, then making the sample and the auxiliary electrode contact with the solution, preparing a frequency generator connecting the sample and the auxiliary electrode respectively, choosing a frequency, and turning on the frequency generator with an alternating current of the frequency, monitoring the phase angle measured in the sample, and determining the formation of cracks in the sample by checking whether the phase angle measured in the sample increases with time.
    Type: Grant
    Filed: June 15, 1994
    Date of Patent: July 16, 1996
    Assignee: Industrial Technology Research Institute
    Inventor: Iuan-Jou Yang
  • Patent number: 5508624
    Abstract: A degradation level of transformer insulating oil can be checked by measuring leakage current of a sensor for measuring the degradation level of the insulating oil, in which DC power is applied to two electrodes of the sensor in the insulating oil for the transformer. In general, free carbons or nonsolute conductive particles are produced in the transformer insulating oil when used over long periods in the power transformer. The porous ceramic of the sensor for measuring degradation level of the insulating oil receives in the pores thereof the conductive impurity particles, and a conductive circuit is formed. Thus, this measurement for degradation level of insulating oil is based on the electric change states for the formation of the conductive circuit. Accordingly, by forming such structures, a method and apparatus for measuring degradation level of insulating oil by measuring leakage current of the sensor are provided.
    Type: Grant
    Filed: September 7, 1994
    Date of Patent: April 16, 1996
    Assignees: Korea Electrotechnology Institute, Kangnam Industrial Co., Ltd.
    Inventors: Young K. Chon, Kyung H. Ko
  • Patent number: 5504433
    Abstract: During operation of a fuel cell stack, electrolyte within individual fuel cells migrates between the cathode side and the anode side, and across the separator plate between the cathode side and the anode side electrolyte reservoir plate of a second cell. An electrochemical sensor comprised of wires, a sheath, and a porous conduit having a pore size distribution which is similar to that of the electrolyte reservoir plate in which the electrochemical sensor is located, is capable of determining the electrolyte content during fuel cell operation by measuring the electrical resistance between the wires. The conduit wicks electrolyte into its pores to a content similar to that of the electrolyte reservoir plate. This electrolyte establishes electrical contact between the wires such that the measure of the electrical resistance between the wires is related to the electrolyte content of the electrolyte reservoir plate.
    Type: Grant
    Filed: October 23, 1992
    Date of Patent: April 2, 1996
    Assignee: International Fuel Cells Corporation
    Inventor: Harold R. Kunz
  • Patent number: 5482855
    Abstract: A taste sensor has a lipid membrane including lipid molecules and a membrane-forming material for accommodating at least some of the lipid molecules on its surface. The lipid membrane induces a change in electrical characteristics, when a taste substance reacts with the surface of the lipid membrane. A signal processing unit receives a signal indicating a change in electrical characteristics induced by the taste sensor and generates data for determining the taste of the taste substance.
    Type: Grant
    Filed: March 8, 1993
    Date of Patent: January 9, 1996
    Assignees: Anritsu Corporation, Kaoru Yamafuji, Kiyoshi Toko, Kenshi Hayashi
    Inventors: Kaoru Yamafuji, Kiyoshi Toko, Kenshi Hayashi
  • Patent number: 5483166
    Abstract: An electrochemical test cell for measuring conductivity and transport properties of a solid or liquid electrolyte comprises a longitudinal chamber, produced, e.g., from a syringe, a pair of electrodes and means for holding the electrodes which defines an adjustable volume for containing the electrolyte and which aids in maintaining contact between the electrolyte and the electrode.
    Type: Grant
    Filed: April 2, 1993
    Date of Patent: January 9, 1996
    Inventor: Ib I. Olsen
  • Patent number: 5466366
    Abstract: A water temperature and conductivity detector includes a detector unit, a cup-shaped bottom shell, and a socket connector having a top end connected to the detector unit, a bottom end connected to the cup-shaped bottom shell, a water inlet connected to a water supply system, and a water outlet connected to a reverse-osmosis water purifier system, the detector unit having two electrodes projected into the cup-shaped bottom shell to detect the conductivity of water passing from the water supply system to the reverse-osmosis water purifier system, and a heat sensitive resistor to compensate the temperature of water passing through the detector.
    Type: Grant
    Filed: February 1, 1994
    Date of Patent: November 14, 1995
    Assignee: New Gulf Measurement Instrument Ltd. Company
    Inventor: Huang Chia-ching
  • Patent number: 5441049
    Abstract: A conductivity meter includes a cell having a passageway through which dialysate flows during measurement. A constriction in the passageway meters the flow and partially defines the cell constant. To measure conductivity, an alternating current is applied to the dialysate through cylindrical electrodes in the passageway on each side of the constriction. A thermistor adjacent one of the electrodes is used to measure the temperature of the dialysate. A housing for the cell includes an elongated handle and an enlarged portion, containing the cell, extending to one side of the handle. The handle contains a printed circuit board having circuitry for making the measurement and the enlarged portion includes a window for display of the measurement.
    Type: Grant
    Filed: December 28, 1992
    Date of Patent: August 15, 1995
    Assignee: Automata Medical Instrumentation, Inc.
    Inventor: Thomas M. Masano
  • Patent number: 5432453
    Abstract: A cartridge-shaped reference element for potentiometric measuring systems exhibits a hollow body (20) as well as first and second sealed ends (30, 40) and a chamber (60). A silver electrode is provided as at least partial coating (50) of the inner surface of hollow body (20) bordering chamber (60), and coating (50) and protruding from chamber (60) so that a potential relating to the reference element can be measured.
    Type: Grant
    Filed: October 27, 1993
    Date of Patent: July 11, 1995
    Assignee: Schott-Gerate GmbH
    Inventors: Andrea Dornauf, Werner Gehringer, Gunter Tauber
  • Patent number: 5417100
    Abstract: A novel, inexpensive sensor (10) for detecting volatile hydrocarbons and other solvent vapors detects leaks in the fittings and valves of petroleum refineries and chemical manufacturing and processing plants. The sensor comprises (a) a dielectric substrate (12) having a major surface; (b) a pair of interdigitated, electrically conductive electrodes (14a, 14b) disposed on the major surface of the substrate; and (c) a composite coating (16) covering the interdigitated electrodes and comprising (1) a conductive polymer, and (2) a dielectric polymer with an affinity for the solvent vapors to be detected.
    Type: Grant
    Filed: March 10, 1993
    Date of Patent: May 23, 1995
    Assignee: Hughes Aircraft Company
    Inventors: Leroy J. Miller, Camille I. van Ast, Frederick G. Yamagishi
  • Patent number: 5408185
    Abstract: Apparatus for automated polyelectrolyte measurement of liquid process materials including a sample vessel which defines an electrically insulating, cylindrical cavity below a larger-diameter reservoir. Electrodes are located at the ends of the cylindrical cavity and an insulating piston is reciprocated with a predetermined, small clearance within the cavity. The charge displacement is measured between the electrodes. An outlet channel opening at the floor of the cylindrical cavity is connected to an outlet pipe. A rinsing duct with valve control for introducing a rinsing fluid into the reservoir. A controller is connected to an actuator for reciprocating the piston, to a valve in the outlet pipe and to the rinsing valve. After each polyelectrolyte measurement the substance under test is removed from the sample vessel through the outlet channel, rinsing fluid is introduced, and the rinsing fluid is removed through the outlet channel while the piston reciprocates.
    Type: Grant
    Filed: November 18, 1992
    Date of Patent: April 18, 1995
    Assignee: Mutek GmbH
    Inventor: Robert Krah
  • Patent number: 5374380
    Abstract: Salinity control of sump water in an evaporative cooler (10) wherein a pump (19) continuously impels a water flow from a sump (11) to an evaporative surface where some of the water is evaporated by air flow from a fan (15, 16). Control is affected by sensing electrical resistance of the sump water with monel probes (36) energised with low voltage alternating current, and initiating an "ON" period of a timer (quad NOR gate) when resistance drops below a preset level. During the "ON" period a solenoid valve (25) is opened in a bleed line and some only of the pumped sump water is passed to drain, without interruption of cooler operation.
    Type: Grant
    Filed: December 23, 1992
    Date of Patent: December 20, 1994
    Assignee: F F Seely Nominees Pty Ltd.
    Inventor: Robert W. James
  • Patent number: 5337018
    Abstract: A sensor (10) is provided, which is based on a conductive polymer (16) as the active material to measure the concentration of alcohol in gasoline. This information is then sent to the engine to immediately adjust the air:fuel ratio, which is critical in these alternate fuel systems for the smooth operation of the engine. The sensor of the invention comprises the conductive polymer and a pair of sensing electrodes (12, 14) associated with the conductive polymer. Most conveniently, the sensing electrodes are arranged in an interdigitated fashion and are coated with the conducting polymer. Certain conducting polymers have been found whose resistance changes as a function of alcohol, e.g., methanol, concentration. Since the resistance of the conducting polymer is related to the alcohol concentration, this information can be processed by a microprocessor, which can then make the necessary adjustments in the air:fuel ratio.
    Type: Grant
    Filed: November 13, 1992
    Date of Patent: August 9, 1994
    Assignee: Hughes Aircraft Company
    Inventor: Frederick G. Yamagishi
  • Patent number: 5331287
    Abstract: A sensor for monitoring the water content and the acid content in the presence of water in nonaqueous media can be incorporated into a monitoring system for monitoring the quality of nonaqueous fluids in equipment or vehicles. The sensor comprises an insulating substrate; electrodes formed on the substrate in an interdigitated pattern; and a conductive polymer deposited over the interdigitated electrodes which bridges between adjacent digits of the electrodes. The monitoring system incorporating the sensor comprises a control module for measuring the conductivity of the sensor. The control module is preprogrammed to compare the measured conductivity to a predetermined level indicative of an unacceptable level of degradation. The sensor is made by depositing electrodes on an insulating substrate; depositing a conductive polymer over the electrodes in an amount sufficient to bridge between the electrodes; and neutralizing the conductive polymer to an insulating form.
    Type: Grant
    Filed: July 31, 1992
    Date of Patent: July 19, 1994
    Assignee: Hughes Aircraft Company
    Inventors: Frederick G. Yamagishi, Camille Van Ast, Leroy J. Miller
  • Patent number: 5302903
    Abstract: A throughflow type mastitis detector having an inlet stub and an outlet stub by means of which the mastitis detector can be coupled to a milk tube; a measuring chamber having side walls, a closed bottom, and an opening opposite said bottom in spaced relationship to said inlet stub, through which opening the milk to be monitored, supplied through the inlet stub, can flow into the measuring chamber, and through which the milk can again leave the measuring chamber when the level of the milk within the measuring chamber exceeds the height of the lowest side wall portion; and a pair of electrodes in the bottom of said measuring chamber for measuring the electrical conductivity of the milk, characterized in that at least one of the electrodes has a convex head projecting above the bottom surface and a shank extending through an opening in the bottom.
    Type: Grant
    Filed: October 13, 1992
    Date of Patent: April 12, 1994
    Assignee: N.V. Nederlandsche Apparatenfabriek NEDAP
    Inventors: Hendrik J. De Jong, Albertino B. M. Verstege, Pieter H. Hogewerf
  • Patent number: 5266899
    Abstract: A salt analyzer is disclosed capable of measuring the conductivity of a saline solution when either contact or non-contact probes are used. In particular, the salt analyzer employs circuitry capable of switchably measuring the various electrical parameters necessary for determining the conductivity of a solution when either contact or non contact probes are used.
    Type: Grant
    Filed: January 31, 1992
    Date of Patent: November 30, 1993
    Assignee: Akzo N.V.
    Inventors: Rame W. Bull, Richard T. Prince
  • Patent number: RE36074
    Abstract: A particle detector is designed to detect particles such as cells and blood corpuscles, and this particle detector includes means for passing and recovering a multilayer flow consisting of an inner layer A of conductive liquid specimen, a middle layer B of conductive first sheath liquid, and an outer layer C of nonconductive second sheath liquid surrounding them, in an orifice 12, and a pair of electrodes disposed on both sides of the orifice so as to contact the conductive liquid respectively. A detector circuit 44 is connected to the pair of electrodes so as to detect a particle signal on the basis of difference of electric impedance between the electrodes. The diameter of the orifice 12 is substantially the diameter of the middle layer. By varying the flow rate balance of the conductive liquids and nonconductive liquid, the diameter of the middle layer may be freely changed. Accordingly, the diameter of the orifice may be apparently changed as desired.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: February 2, 1999
    Assignee: Toa Medical Electronics Co., Ltd.
    Inventor: Chihiro Kouzuki