To Determine Water Content Patents (Class 324/694)
  • Publication number: 20030067311
    Abstract: A system is disclosed for monitoring the quality of an internal fluid contained in an apparatus. The system includes a pulse input port, a test gap unit, and a reactive impedance unit. The pulse input port receives a test pulse input signal from a pulse source. The test gap unit provides a test voltage across a test gap while the test gap unit is immersed in the internal fluid within the apparatus. The test gap means has an inherent capacitance. The reactive impedance unit provides an impedance in series with the inherent capacitance of the test gap unit that restricts transfer of current to the test gap, and is coupled to the pulse input port and coupled to the test gap unit.
    Type: Application
    Filed: December 6, 2001
    Publication date: April 10, 2003
    Inventors: Timothy L. Cargol, Chathan M. Cooke
  • Publication number: 20030057969
    Abstract: A method for determining a level of water contamination in a fuel containing ethanol, including determining the ethanol concentration of the fuel; sensing the resistance of the fuel; determining a resistance limit of the fuel; and comparing the resistance to the resistance limit to provide the level of water contamination. Ethanol concentration is preferably obtained by comparing a measured capacitance to known values in a look-up table. The resistance limit can be determined by multiplying a resistance corresponding to the ethanol concentration by an alarm fraction. The resistance is obtained by a look-up table of resistance values at known water contamination levels. Reporting occurs when the measured resistance is at or below the resistance limit. Alternatively, the measured resistance is normalized with respect to the resistance with no water contamination and reporting occurs when −1.6667*normalized resistance+1.6667 approaches 1.0.
    Type: Application
    Filed: September 24, 2001
    Publication date: March 27, 2003
    Inventors: Su-Chee Simon Wang, Yingjie Lin
  • Publication number: 20030011386
    Abstract: A method and apparatus is disclosed for estimating brine water conductivity in a multiphase mixture of brine water and other substances by combining measured mixture permittivity and conductivity with a known or derived relationship between brine water conductivity and brine water permittivity. The mixture permittivity and conductivity are measured using an open-ended coaxial probe or other means at microwave frequencies. A number of applications for the brine water conductivity estimate are disclosed including making salinity corrections of a dual energy flow meter.
    Type: Application
    Filed: May 30, 2002
    Publication date: January 16, 2003
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Gheng-Gang Xie, Gerard Segeral, Gilles Roux, Paul Hammond
  • Patent number: 6499338
    Abstract: Moisture management indexes are determined for a textile sandwiched between two plates. Electrical conductors arranged in concentric opposing pairs are used to measure changes in electrical resistance of the fabric. A quantity of water (or other chosen liquid) is poured down a guide pipe and changes of resistance measured against time. From this data, specific indexes are determined, in a repeatable fashion, and used for determining moisture management characteristics of the fabric.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: December 31, 2002
    Assignee: Hong Kong Polytechnic University
    Inventors: Yi Li, Weilin Xu, Kwok-wing Yeung, Yi-lin Kwok
  • Publication number: 20020118027
    Abstract: The present invention discloses a type of nanostructured ceramic platform for gas sensors and sensor arrays. These sensors comprise micromachined anodic aluminum oxide films, which contains extremely high density (e.g., 1011 cm−2) nanoscale pores. Sensing materials deposited inside this self-organized network of nanopores have ultra-high surface area and nanometer grain structure, therefore enabling high sensitivity. Refractory nature of alumina ceramic enables the desired robustness, long lifetime and stability in harsh environment. This sensor platform can been used for both chemical gas and physical (humidity, temperature) sensors and sensor arrays.
    Type: Application
    Filed: October 24, 2001
    Publication date: August 29, 2002
    Inventors: Dmitri Routkevitch, Peter Mardilovich, Alex Govyadinov, Stephanie Hooker, Stephen S. Williams
  • Patent number: 6441622
    Abstract: A method and apparatus for time domain reflectometry sensing of moisture in a test material. The sensor (200) having a generally helical shaped electrode (206) and at least one secondary electrode (208) spaced apart from the generally helical shaped electrode (206) to enable the test material to be present in the space (210) between the helical shaped electrode (206) and the secondary electrode (208). A wave pulse generator (202) is coupled to the generally helical shaped electrode (206) and the secondary electrode (208) that results in a reflection of the generated wave from the wave pulse generator (202). Additionally, a reflected pulse detector (204) is coupled to the generally helical shaped electrode (206) and the secondary electrode (208), in which the reflected wave pulse detector (204) receives a reflected wave pulse from the wave pulse generator (202).
    Type: Grant
    Filed: August 18, 2000
    Date of Patent: August 27, 2002
    Assignee: Motorola, Inc.
    Inventors: Stanley Wrzesinski, Daniel A. Young
  • Patent number: 6426629
    Abstract: Methods and apparatus for measuring electrical parameters of a test fluid are disclosed. The methods include maintaining the test fluid and a reference fluid at the same temperature and in thermal proximity to each other, equalizing the temperature of the test fluid and the reference fluid prior to the measuring step, measuring the electrical parameter of the test fluid and the reference fluid at substantially the same time, and standardizing the measurement to a predetermined temperature. The apparatus includes a heat exchanger for maintaining the flow of a primary heat exchange fluid in thermal proximity to the test fluid in the reference fluid, and a metal wall having one surface in contact with a measuring cell and another surface in contact with the flow of the primary heat exchange fluid whereby the measuring cell and the heat exchanger are separated thereby.
    Type: Grant
    Filed: July 10, 1998
    Date of Patent: July 30, 2002
    Assignee: Gambro AB
    Inventors: Raymond Edgson, Eric Wilkinson
  • Patent number: 6377058
    Abstract: A device for sensing moisture in moving hay bales has a pair of star-shaped wheels situated to have points penetrate into the bale and be driven by the bale. The points establish electrode surfaces within the bale between which resistivity or conductivity of an electrical current may be measured and scaled to moisture content of the hay of the bale.
    Type: Grant
    Filed: December 9, 1999
    Date of Patent: April 23, 2002
    Assignee: Harvest TEC, Inc.
    Inventor: Peter Pemrick
  • Patent number: 6370945
    Abstract: The invention provides a leak detection system comprising a conduit for carrying a fluid or gas and a control device for monitoring leaks in the conduit. The conduit is formed from first and second electrically conductive layers that are electrically insulated from each other. The control device includes an output, for introducing an electric charge to the first and second layers, a detector for detecting changes in the electric charge introduced to layers, and a response switch for triggering a predetermined response when a sufficient change in the electric charge is detected.
    Type: Grant
    Filed: August 20, 1998
    Date of Patent: April 16, 2002
    Inventor: Michael Lee Roberts
  • Publication number: 20010018845
    Abstract: The invention provides a leak detection system comprising a conduit for carrying a fluid or gas and a control device for monitoring leaks in the conduit. The conduit is formed from first and second electrically conductive layers that are electrically insulated from each other. The control device includes an output, for introducing an electric charge to the first and second layers, a detector for detecting changes in the electric charge introduced to layers, and a response switch for triggering a predetermined response when a sufficient change in the electric charge is detected.
    Type: Application
    Filed: August 20, 1998
    Publication date: September 6, 2001
    Inventor: MICHAEL LEE ROBERTS
  • Patent number: 6272915
    Abstract: A system for evaluating multiphase fluid flow in a wellbore. Two distinct AC signals are injected into a fluid. One AC signal originates from a transmitter electrode in ohmic contact with the fluid, and the other AC signal originates from a transmitter electrode capacitively coupled to the fluid. The geometric factors between the electrode pairs are selected to distinguish between different constituents within the wellbore fluids. The output electrical impedance of the ohmic transmitter is low so that the AC signal from the capacitive transmitter is shunted to signal ground in electrically conductive fluids. A single detector can measure the fraction of electrically conductive water covering the detector electrode as well as the dielectric constant of an oil and gas mixture. Arrays of such detector electrodes can measure the holdups and velocities of the constituent fluids in a flowing multiphase fluid.
    Type: Grant
    Filed: April 23, 1999
    Date of Patent: August 14, 2001
    Assignee: Baker Hughes Incorporated
    Inventors: Richard J. Kostelnicek, Peter W. Reittinger
  • Patent number: 6240778
    Abstract: A liquid level sensor for detecting when an upper level of a liquid in a reservoir has reached a predetermined or critical point in the reservoir. The sensor includes a first input plate and a second input plate disposed concentrically relative to the first input plate. Each of the input plates are further of a shape such that an imaginary line extending through the centroid of the first input plate divides each of the first and second input plates approximately in half. An output or receiver plate is positioned closely adjacent the two input plates. The input plates are further disposed in the reservoir such that the centroid is at the predetermined or critical level in the reservoir. The two input plates are alternately electrically excited and the signals coupled to the output plate are detected and repeatedly compared against one another. The output signals will differ in magnitude because of the difference in the dielectric constant of air and the liquid in the reservoir.
    Type: Grant
    Filed: March 2, 1998
    Date of Patent: June 5, 2001
    Assignee: KDI Precision Products, Inc.
    Inventors: Alan R. Hannan, Thomas M. Nickolin, Bryan H. McQuitty, William E. Atkinson, J. Jacob Noble
  • Patent number: 6229318
    Abstract: An electrical resistance type humidity sensor is herein disclosed which comprises a humidity sensor in which electrodes are formed on a woodceramics substrate having linear characteristics with humidity, and a temperature sensor for temperature correction in which electrodes are formed on other woodceramics substrate having the identical characteristics as in the woodceramics humidity sensor and a film coating of a nonhygroscopic material is formed on the surface of the substrate. Thus, a resistance value measured by the woodceramics humidity sensor is corrected on the basis of a resistance value measured by the woodceramics temperature sensor to obtain an output voltage in proportion to a relative humidity. A structure insensitive to a humidity formed from all the same material i.e.
    Type: Grant
    Filed: January 15, 1998
    Date of Patent: May 8, 2001
    Assignees: Suda Toshikazu, Sanriki Kogyo Kabushiki Kaisha
    Inventor: Toshikazu Suda
  • Patent number: 6204672
    Abstract: A measurement apparatus for sensing three properties of materials including a fixed impedance element coupled in series with the sensor array between an input signal and a reference potential (e.g. ground). The sensor array exhibits a variable impedance resulting from changes in physical characteristics of the material. The variable impedance of the sensor array relates to changes in property of the material being sensed which can then be related to changes in other physical characteristics of the material such as weight, chemical composition, and temperature. The reduced size and increased resolution of the sensor array is particularly adaptive to a twin mesh sheetmaking system.
    Type: Grant
    Filed: April 25, 2000
    Date of Patent: March 20, 2001
    Assignee: Honeywell International Inc
    Inventor: Lee Chase
  • Patent number: 6202479
    Abstract: A soil moisture monitoring apparatus, system and method for monitoring the soil moisture content of a given volume of soil in which a plant is growing are provided. The apparatus, system and method allow a plant caretaker to be alerted when the soil moisture content in the soil drops below a pre-determined level. When the soil moisture content drops below a predetermined level, an audible signal may be generated alerting the plant caretaker of the need to add water. The audible signal generated generally corresponds to a recognizable sound that a creature embodied by a creature-shaped housing makes in nature. The creature-shaped housing containing the audible signal generator mechanism may be placed around or attached to the plant such that the audible signal may be readily heard and the creature-shaped housing is visible.
    Type: Grant
    Filed: May 12, 1999
    Date of Patent: March 20, 2001
    Inventor: Scott Frybarger
  • Patent number: 6138754
    Abstract: A system for use in a subterranean well includes a production tubing and a valve. The production tubing has a port to receive well fluid from a formation. The valve is mounted to the production tubing and includes a sealed housing, a motor, a valve cover, an actuator drive and a sensor. The motor is located inside the housing, and the actuator drive is actuated by the motor to move the valve cover over the port to selectively control the communication of the well fluid between the formation and the passageway of the tubing. The sealed housing may permit the well fluid to accumulate inside the housing over time. The sensor is located inside the housing and provides an indication of the amount of well fluid that has accumulated inside the housing. This information may be useful for such exemplary purposes as predicting when the valve will fail and for evaluating the condition of the valve.
    Type: Grant
    Filed: November 18, 1998
    Date of Patent: October 31, 2000
    Assignee: Schlumberger Technology Corporation
    Inventors: Anthony F. Veneruso, Gerald W. Robertson
  • Patent number: 6119059
    Abstract: An advance warning device for monitoring the working conditions of a hydraulic braking system of a motor vehicle is composed of a plurality of sensors and a controller in communication with the sensors for processing the signals transmitted by the sensors so as to provide the operator of the motor vehicle with an advance warning signal as to likelihood of the brake failure. The sensors are intended to monitor respectively the temperature of the brake lining piece, the temperature of the brake fluid kept in the distribution pump, the water content of the brake fluid of the hydraulic braking system, and the hydraulic pressure of the hydraulic braking system.
    Type: Grant
    Filed: March 26, 1998
    Date of Patent: September 12, 2000
    Assignee: Institute Of Occupational Safety And Health, Council Of Labor Affairs, Executive Yuan
    Inventors: Chi-Fu Tai, Shih-Hsiung Wu, Chung-Yun Gau, Shuo-Jen Lee, Ke-Feng Lin
  • Patent number: 6114863
    Abstract: An improved process for determining the presence of water in a material is disclosed. A set of electrodes is placed on the surface of a layer of the material being monitored, and an electric field is established therebetween. The phase angle for the electric field at a pre-selected frequency is measured, and compared with a predetermined phase angle for a dry portion of the material. A significant difference between the phase angle for the material being monitored and the predetermined phase angle is indicative of the presence of water in the material. The material being monitored may be an electrical insulating material, e.g., for conductive components in water-cooled electrical generators. Electrical generators monitored in this manner are also within the scope of this disclosure.
    Type: Grant
    Filed: April 29, 1998
    Date of Patent: September 5, 2000
    Assignee: General Electric Company
    Inventors: John Raymond Krahn, Clive William Reed
  • Patent number: 6087837
    Abstract: A measurement apparatus for sensing three properties of materials including a fixed impedance element coupled in series with the sensor array between an input signal and a reference potential (e.g. ground). The sensor array of the apparatus is an electrode configuration which includes a first elongated electrode coupled to the reference potential and second and third segmented elongated electrodes being parallel to and essentially in the same plane as the first elongated electrode. The segments within the second and third electrodes are configured such that the segments in the second electrode are staggered with respect to segments in the third electrode thereby minimizing or eliminating spacing between detection cells within the sensor array, reducing overall size of the sensor array and increasing measurement resolution. The sensor array exhibits a variable impedance resulting from changes in physical characteristics of the material.
    Type: Grant
    Filed: November 21, 1997
    Date of Patent: July 11, 2000
    Assignee: Honeywell-Measurex
    Inventor: Lee Chase
  • Patent number: 6088657
    Abstract: A hay bale moisture measuring device comprising a bimetalic, probe forming a single cell battery uses the hay and the moisture therein as the electrolytes to provide an internal cell resistance measurement which is calculated in an electronic circuit according to a predetermined algorithm into a hay moisture measurement which is further biased for hay temperature, bale configuration, hay type, cutting and density by the same circuit.
    Type: Grant
    Filed: December 30, 1997
    Date of Patent: July 11, 2000
    Assignee: Farmex, Inc.
    Inventor: Michael T. McMahon
  • Patent number: 6084417
    Abstract: In a method and a system for the operation of a resistive moisture sensor, conductance of the sensor is measured, whereby current through the moisture sensor is measured preferably during an application of a voltage to the moisture sensor. In order to avoid electrolytic phenomena, the voltage is fed to the moisture sensor via a capacitor, and has a waveform of two pulses of different polarity following shortly one after the other.
    Type: Grant
    Filed: November 8, 1995
    Date of Patent: July 4, 2000
    Assignee: Mannesmann VDO AG
    Inventor: Reinhold Berberich
  • Patent number: 6037784
    Abstract: Material resistivity measuring apparatus includes a transmitter for transmitting a measurement frequency current through the material to a receiver spaced from the transmitter. The transmitter includes a power amplifier wherein the measurement frequency current is amplified in discrete steps depending upon resistivity of the material. The current level of the transmitter is transmitted to the receiver by modulating the measurement frequency current by a modulation signal whose phase is indicative of power level. The measurement frequency current can be modulated by a second modulating signal which provides a reference phase for the first modulating signal.
    Type: Grant
    Filed: March 16, 1999
    Date of Patent: March 14, 2000
    Assignee: Geometrics
    Inventor: Kenneth R. Smith
  • Patent number: 5994908
    Abstract: A portable grain moisture meter has a large 16 character digital display allowing an alphabetical list of grain selections to be selectably displayed in full text fonnat and subsequently tested for moisture content with the test results also displayed on the same display. The alphabetical display of grains may be changes to various differing languages with the alphabetical display remaining intact. Certain grains may be deleted from the alphabetical display to provide a sequential display of only frequently tested grains.
    Type: Grant
    Filed: August 29, 1997
    Date of Patent: November 30, 1999
    Assignee: Worens Group Inc.
    Inventor: Mike Mc Mahon
  • Patent number: 5959457
    Abstract: In a circuit arrangement for measuring the resistance of a resistance sensor, for instance a wetness sensor, which is connected to an evaluation circuit, there is a galvanic separation, formed preferably by an isolating transformer, between the resistance sensor and the evaluation circuit.
    Type: Grant
    Filed: July 2, 1997
    Date of Patent: September 28, 1999
    Assignee: VDO Adolf Schindling AG
    Inventor: Reinhold Berberich
  • Patent number: 5861758
    Abstract: A process and a system for the operation of a resistive moisture sensor, in particular on the windshield of a motor vehicle, wherein the conductivity of the moisture sensor is measured shortly after a sudden change in a signal fed to the moisture sensor and measured at at least one later time. Information as to the nature and degree of the dirtying of the windshield is obtained by the measured values.
    Type: Grant
    Filed: July 30, 1997
    Date of Patent: January 19, 1999
    Assignee: VDO Adolf Schindling AG
    Inventor: Reinhold Berberich
  • Patent number: 5857379
    Abstract: A hair-care appliance measures the moistness of the hair by measuring the resistance (R.sub.x) of the hair between measurement electrodes (14A/14B). The hair resistance (R.sub.x) is included in a T network comprising a first resistor (20) driven by a voltage source (28) and a second resistor (24). The signal current (I.sub.s) through the second resistor is measured and converted into a measurement signal (MS) by a converter (30). As a result of the use of the T network a comparatively large resistance variation of the hair resistance (R.sub.x) is required for a given amplitude variation in the signal current (I.sub.s). This allows measurements over a wider resistance range while the resolution is maintained.
    Type: Grant
    Filed: September 11, 1996
    Date of Patent: January 12, 1999
    Assignee: U.S. Philips Corporation
    Inventors: Klaas J. Lulofs, Petrus J. Bremer
  • Patent number: 5847568
    Abstract: Disclosed is a control system for regulating irrigation to an area of land. The irrigation control system includes a control unit, a photosensor, a timer or controller and a moisture probe for sensing the moisture level in the area to be watered. The control unit is configured to disable power to the system if the moisture level in the area of land exceeds a predetermined level as measured by the moisture probe, which is buried in the watering area. In a preferred embodiment, the moisture probe consists of two electrode plates, preferably manufactured of high purity copper, that are oriented parallel to one another. The electrode plates each have a predetermined length and thickness and are separated by a predetermined distance, each of which are configured to optimize the moisture detecting characteristics of the probe. The control unit applies an electrical potential across the electrode plates such that the resistance of the soil located therebetween varies as a function of moisture content.
    Type: Grant
    Filed: June 3, 1997
    Date of Patent: December 8, 1998
    Inventors: Robert M. Stashkiw, Dean L. Cramer
  • Patent number: 5841282
    Abstract: Device for measuring soil conductivity is comprised of a frame adapted to be conveyed over a ground surface and plurality of soil engaging coulters insulated from each other and insulatively mounted to this frame. This device also includes means for passing a current between a first pair of coulters through the soil and means for measuring this current. It further comprises means for measuring the resulting voltage between a second pair of coulters. This device for measuring soil conductivity also is comprised of electrical contact members which provide consistent electrical contact from the coulter to the means for measuring current and voltage. An electrical signal received by a coulter travels to a mounting flange and then to a dust cap. The dust cap passes this electrical signal to the spindle by way of a spring-loaded plunger. This electrical signal travels from the fixed spindle to the means for measuring current and voltage.
    Type: Grant
    Filed: February 10, 1997
    Date of Patent: November 24, 1998
    Inventors: Colin Christy, Eric Lund
  • Patent number: 5835018
    Abstract: A low water level indicator includes a detection assembly and an indicator unit. The detection assembly comprises a housing, a pair of electrodes, a control unit, and a battery. The indicator unit comprises a light emitting diode (LED) and a base plate. The housing is preferably molded as two halves which are joined at assembly. An adjustment rod is held by a first and second snap retainer at substantially the bottom of the housing. The adjustment rod is used to adjust the height of the bottom of the housing relative to a water container. The electronic control circuit is mounted in a top cavity. A hook rod is held by a top spring clip which is disposed at substantially the top of the housing. The hook rod is used to provide stability for the placement of the detection assembly. When the water level in a water container is too low, electrical current will no longer pass from the first electrode to the second electrode through the water.
    Type: Grant
    Filed: July 24, 1997
    Date of Patent: November 10, 1998
    Inventors: Thomas C. Kursel, Robert E. Radke
  • Patent number: 5818241
    Abstract: Moisture sensing apparatus that uses slow wave transmission lines. Such transmission lines include a helically wound inner core, a surrounding outer conductor, and a moisture bearing material between the inner core and the outer conductor. Preferably, the transmission line includes a moisture barrier that separates the transmission line into a sealed dry section and a wet section which is in moisture communication with its environment. The moisture sensing apparatus further includes a source of electrical signals on the transmission line, and a moisture sensing circuit, operatively connected to the slow wave transmission line, which senses the moisture content of the moisture bearing material from the velocity of the impressed electrical signals on the slow wave transmission line. Preferably, the velocity of the impressed electrical signals is obtained indirectly using a sing-around measurement technique.
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: October 6, 1998
    Inventor: John M. Kelly
  • Patent number: 5801539
    Abstract: A moisture sensor has two spaced main electrodes which are arranged on the outer side of the windshield of a motor vehicle in a region which is passed over by the windshield wiper and are connected to an evaluation circuit for the determination of resistance as a function of a degree of moisture. In order to improve the precision of the measurement results supplied by the moisture sensor, an auxiliary electrode is arranged between the two main electrodes outside a region passed over by the wiper in order to determine a shunt resistance formed by residues on the windshield and/or in the region of a windshield gasket covering. The main electrodes and the auxiliary electrode lead to an evaluation circuit.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: September 1, 1998
    Assignee: VDO Adolf Schindling AG
    Inventor: Hans-Joachim Schroder
  • Patent number: 5795994
    Abstract: Condensed moisture in devices and/or pipe conduits for anti-corrosion applications in chemical engineering is measured at least one point in the devices and/or pipe conduits by measuring an electrochemical potential difference across two different elements, such as iron and copper, which are arranged one beside the other spaced from 0.001 to 1 mm from each other by an electrically insulating material so as to be electrically insulated from each other. An apparatus for making these measurements is also described.
    Type: Grant
    Filed: November 25, 1996
    Date of Patent: August 18, 1998
    Assignee: Metallgesellschaft Aktienegesellschaft
    Inventors: Horst Kalfa, Knut Schroeder
  • Patent number: 5783743
    Abstract: A sensor for detecting moisture on a non-conductive support, in particular a windshield of a motor vehicle, has one or more metallic, electrically conductive layers which are arranged in a given pattern on the outer surface of the support. The metallic, electrically conductive layer is produced from a metallic resinate which is applied to the support and then burned-in by the action of heat. Also deseribed is a method for constructing such a moisture sensor whit applies a glass layer in the form of a glass frit paste to be sintered upon the metallic electrically conductive layer, where the burning-in of the metallic resinate and the sintering of the glass frit paste are effected in single step.
    Type: Grant
    Filed: June 27, 1996
    Date of Patent: July 21, 1998
    Assignee: VDO Adolf Schindling AG
    Inventor: Klaus Weber
  • Patent number: 5780718
    Abstract: A rain sensor for the windshield of a vehicle has one or more electrically conductive layers which are arranged in a given pattern upon the outer surface of such windshield, and is constructed as a laminate of conductive and resistive layers formed by process steps of printing and sintering for construction of electrodes of the sensor. A conductive layer is formed of a mixture of electrically conductive particles and a glass frit which melts at a lower temperature than a melting temperature of the material of the window which serves as a support for the sensor. The conductive paste is applied with a heating action step, in the configuration of an electrode structure, by sintering to the window.
    Type: Grant
    Filed: May 17, 1996
    Date of Patent: July 14, 1998
    Assignee: VDO Adolf Schindling AG
    Inventor: Klaus Weber
  • 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: 5730024
    Abstract: The invention relates to a test probe (1) primarily intended to be applied in structural material (2) during the production and/or building stage or when water damage has occured in a building and in which moisture measurement can be done undisturbed from outer factors in following the drying out process of built in moisture or other inconvenient, supplied moisture which can cause troubles in the form of mold and/or damages caused by putrefaction, as well as damages on floor coverings and other structural elements. The test probe (1) comprises an active part (3) of a hygroscopic material which is enclosed in an outer, mechanical cover (4), said cover has that property to allow passage of water steam, but prevents passage of water in liquid.
    Type: Grant
    Filed: February 16, 1995
    Date of Patent: March 24, 1998
    Assignee: Sahlens Fuktkontroll
    Inventor: Nicklas Sahlen
  • Patent number: 5700961
    Abstract: A system and method for measuring the stickiness of agricultural solids such as cotton is provided. A reference moisture level of a sample is measured in a manner not responsive to the presence of sugars. The sugar-based moisture content of the sample is measured by sensors responsive to the presence of sugars. The difference between the reference moisture level and the sugar-based moisture content provides a measure of the relative stickiness of the sample.
    Type: Grant
    Filed: June 19, 1996
    Date of Patent: December 23, 1997
    Assignee: The United States of America as represented by the Secretary of Agriculture
    Inventors: William S. Anthony, Richard K. Byler
  • Patent number: 5663650
    Abstract: A portable grain moisture meter has a large 16 character digital display allowing an alphabetical list of grain selections to be selectably displayed in full text format and subsequently tested for moisture content with the test results also displayed on the same display. The meter also has provisions for calibrating the meter to a remotely located meter and has dual temperature transducers for achieving automatic grain temperature compensation by monitoring both the grain temperature along with the cell temperature.
    Type: Grant
    Filed: August 1, 1995
    Date of Patent: September 2, 1997
    Assignee: Farmex, Inc.
    Inventor: Mike McMahon
  • Patent number: 5661227
    Abstract: Microwave clothes dryer with a moisture sensor having an array of short coaxial cables extending through an electrically conductive base plate which is grounded to the shielding structure of the dryer. The ends of the cables are flush with one side of the plate and are exposed for contact with clothes in the dryer chamber. Electrical resistance is monitored between the inner conductors and the plate to determine the dryness of clothes, and the dryer is shut down when the resistance reaches a predetermined level.
    Type: Grant
    Filed: November 14, 1995
    Date of Patent: August 26, 1997
    Assignee: Electric Power Research Institute
    Inventors: Richard D. Smith, Ronald R. Lentz, Patrick C. Meachim
  • Patent number: 5656767
    Abstract: A method and apparatus for automatically detecting a lubricant type and the relative quantity of water present in a test sample of lubricating oil includes the use of an open grid capacitive sensor element that incorporates the lubricating oil as a dielectric medium. The sensor element grid is energized by a frequency variable oscillator that automatically responds to changes in the oil dielectric constant with corresponding frequency changes. As a reference, a sample of new or uncontaminated test oil is confined in wet surface contact with the energized, open grid sensor element. Oscillator frequency changes are measured and recorded, either continuously or at frequent intervals, over a standardized elapsed time interval to generate a reference characterization of the frequency-time relationship distinctive of the particular oil. The same is repeated for a sample of contaminated oil and a corresponding frequency-time relationship generated.
    Type: Grant
    Filed: March 8, 1996
    Date of Patent: August 12, 1997
    Assignee: Computational Systems, Inc.
    Inventors: Raymond E. Garvey, III, Alexander Andrew Carey
  • Patent number: 5652382
    Abstract: An oscillator circuit includes a gate G.sub.11 of C-MOS type (Q.sub.1, Q.sub.2, and the like) having the function of increasing an operating current i with increasing operating frequency. A humidity sensor HS changing electric impedance thereof in accordance with humidity is arranged in part of the oscillator circuit. The oscillator circuit converts a change in humidity into a change in frequency, causes the gate G.sub.11 to convert the change in frequency into a change in operating current i, and outputs the converted change in operating current i. Further, in order to increase the change in operating current i due to the change in frequency, a series circuit consisting of a capacitor C.sub.13 and a resistor R.sub.17 is connected to the gate G.sub.11 as a capacitive load.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: July 29, 1997
    Assignee: TDK Corporation
    Inventors: Shiro Nakagawa, Atsuko Tsuchida, Eiji Takahashi, Kenji Aizawa
  • Patent number: 5619144
    Abstract: Detector and method for detecting the presence of a liquid, such as water dew or of ice, or for detecting a change of phase in liquid, based on a change in an electrical resistance. The detector comprises a substrate onto whose face one or several resistor patterns are applied. For detecting the presence of a liquid or ice or equivalent by a change in the detector resistance, a low-mass detector resistor pattern is applied onto a substrate out of such a metal or equivalent as has a considerable dependence on temperature. On the substrate, there are contact patterns that feed a short pulse of electric current to heat the detector resistor as a short pulse, the presence of a liquid or ice and or a change of phase being detected by the change in resistance taking place during the short pulse. The thickness of the metal film in the resistor pattern (15) of the detector resistor (R.sub.det) is, as a rule, chosen as s<1 .mu.m.
    Type: Grant
    Filed: August 23, 1994
    Date of Patent: April 8, 1997
    Assignee: Vaisala Oy
    Inventor: Lars Stormbom
  • Patent number: 5612490
    Abstract: A profile of the emulsion pad, the oil continuous and the water continuous phases present in a coalescer, such as a crude oil dehydrater or desalter, which contains sample withdrawing means such as trycocks or a swing arm sampler for withdrawing liquid samples from a plurality of known vertical positions inside the unit, is readily obtained by withdrawing samples from a plurality of known vertical positions inside the unit and passing the samples to a receiver outside the unit which contains means for measuring an electrical property determinative of the type of phase being measured and its water content. The measured electrical property may be the energy absorption of the sample, such as RF energy absorption.
    Type: Grant
    Filed: October 31, 1995
    Date of Patent: March 18, 1997
    Assignee: Exxon Research and Engineering Company
    Inventors: Edwin D. Carlson, Salvatore J. Rossetti
  • Patent number: 5600254
    Abstract: In a process and a circuit arrangement for measuring the resistance of a resistance sensor, for instance a wetness sensor, via a rate of change of the charge of a capacitor, a measurement cycle consisting in each case of a charging of a capacitor, a discharging of the capacitor over the resistance sensor, and thereupon a measurement of the charge remaining in the capacitor, the direction of the discharge current through the resistor changes from measurement cycle to measurement cycle.
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: February 4, 1997
    Assignee: VDO Adolf Schindling AG
    Inventor: Reinhold Berberich
  • Patent number: 5568747
    Abstract: The moisture sensor comprises a block of absorbent material, such as wood. Two opposed faces are coated with conductive material, such as paint and two conductors of a cable are connected to the conductive material. The entire element is encapsulated within a sleeve of electrically insulating material, leaving one end face of the block of moisture absorbent material exposed. A plurality of apertures or perforations are provided in the sleeve exposing at least part of the moisture absorbent material. The sensor is adapted to be exposed to an environment to sense the moisture level of that environment.
    Type: Grant
    Filed: September 12, 1994
    Date of Patent: October 29, 1996
    Inventor: Robert H. Lloyd
  • Patent number: 5570030
    Abstract: A sensor for measuring moisture changes in soil and having an electrically insulating cylindrical body along which bare electrical conductors are placed. A transmitter produces constant alternating current which is supplied to the sensor. The voltage which this current creates in the soil is detected by the electrical conductors on the sensor and is fed to a receiver. The receiver consists of electronic circuitry for determining the necessity for allowing irrigation to occur, and if so, switches on a solenoid controlling the water supply. When the sensor indicates sufficient irrigation has occurred, the electronic controls switch the irrigation off. A tube sensor comprising rigid metal tubes of equal length and secured by end members such that no two tubes touch is also provided, for example to measure moisture content changes of any granular material.
    Type: Grant
    Filed: April 17, 1995
    Date of Patent: October 29, 1996
    Inventor: William E. Wightman
  • Patent number: 5546009
    Abstract: A fluid detection system capable of detecting the smallest amount of liquid chemicals, mixtures, aqueous solutions, pure water and others by detecting very low levels of resistance or conductance due to ionization when the liquid substances are subjected to very small amounts of electrical power in a small and localized sampling area. The system includes an electronic control module and a sensing probe. The control module provides strictly limited and controlled amounts of electrical voltage and current to one or more remotely located sensing probes which detect the level of resistance or conductance between two electrodes (gold pins) disposed at a fixed distance from one another. The voltage developed across the electrodes is input to a comparator circuit in the electronic module and compared to a reference to produce a signal defining either a dry or a wet (leak) condition of the sensing probe. This signal can be utilized to generate shutdown signals and/or audible and visual alarms.
    Type: Grant
    Filed: October 12, 1994
    Date of Patent: August 13, 1996
    Inventor: Ian P. Raphael
  • Patent number: 5514973
    Abstract: A system for analyzing the moisture content of bulk cotton or other non-homogeneous flowable solid substrates comprising: an electrical sensor consisting of multiple electrically independent measuring electrodes, each of which independently measures the moisture content of different portions of the sample; a means of pressing the mass against the surface of the sensor to form a face of uniform substrate density on that part of the mass which is pressed against the sensor; means for analyzing such face for moisture content; and a means for releasing the pressure on the halted mass to allow it to resume movement.
    Type: Grant
    Filed: July 11, 1994
    Date of Patent: May 7, 1996
    Assignee: The United States of America as represented by the Secretary of Agriculture
    Inventors: Richard K. Byler, William S. Anthony
  • Patent number: 5450358
    Abstract: A water quality monitoring system (30) assessing the performance of a water purification apparatus (10) which compares the current percentage differential ion concentration or rejection ratio (R.sub.x), between the upstream inlet (12) and downstream outlet (14) of the purification apparatus (10), with a previous sequence of rejection ratios (R.sub.1, . . . R.sub.n) to determine the true performance of the water purification apparatus (10). Each R.sub.x value is determined at a different selected time for use in conjunction with a computation device (40) interconnected between a comparator device (38), calculating R.sub.x, and a storage mechanism (42), storing the sequence of (R.sub.1, . . . R.sub.n) values. The computation device (40) computes a performance value (PV) which is an indication of the filter membrane performance. This performance value is calculated according to a predetermined formula which incorporates the rejection ratios (R.sub.1, . . . R.sub.n) as variables.
    Type: Grant
    Filed: July 15, 1994
    Date of Patent: September 12, 1995
    Assignee: McKesson Corporation
    Inventors: N. Michael Seibert, Hilton L. Stonerock
  • Patent number: 5430384
    Abstract: A resistive soil moisture sensor which is implanted in the soil includes a temperature sensitive component, located at the same soil depth as the sensor. The thermistor is part of a thermistor network which includes other components which are located above ground. The resultant sensor automatically compensates for temperature variations, and is well suited for use with data loggers and automatic control systems.
    Type: Grant
    Filed: July 22, 1994
    Date of Patent: July 4, 1995
    Assignee: Onset Computer Corp.
    Inventor: Lon Hocker