Abstract: A brake oil detector including a housing in which a pipe member, a detecting unit and an alerting unit are disposed. Two ends of the pipe member are respectively connected with two connectors for communicating with an oil draining pipeline for making the brake oil flow through the pipe member during renewal of the brake oil. The detecting unit has a set of electrodes extending into the pipe member. When renewing the brake oil, the set of electrodes serve to detect whether the old deteriorated brake oil has been completely exhausted from the brake pipeline and renewed.

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.

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.

Abstract: There is provided a fluid dynamic bearing evaluating method capable of quantitatively observing a clearance between a shaft 3 and a housing 2 in an operating state and evaluating a fluid dynamic bearing 1 more in detail. This fluid dynamic bearing evaluating method is to evaluate the fluid dynamic bearing 1 by filling a space between the housing 2 and the shaft 3 with an uncharged lubricant, flowing a current through between the housing 2 and the shaft 3 and measuring an electrical resistance value of the fluid dynamic bearing 1 including the lubricant. According to this evaluating method, the lubricant placed between the housing 2 and the shaft 3 is not electrically charged, and therefore, the measured electrical resistance value has a correlation with the clearance between the housing 2 and the shaft 3, and the clearance can be quantitatively observed by this electrical resistance value.

Abstract: A method for determining quality of lubricating oil using electrodes in contact with the oil includes applying a potential having a first amplitude to the electrodes, wherein the first amplitude is sufficiently low such that substantially no solution current will flow; determining a first voltage phase lag with respect to the potential when the potential has the first amplitude; increasing amplitude of the potential to a second amplitude at which solution current flows; determining a second voltage phase lag with respect to the potential when the potential has the second amplitude; and determining the quality of the oil based on the voltage phase lags. A system for practicing the method is also provided.

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.

Abstract: A method for determining quality of lubricating oil includes positioning first and second electrodes in the oil, wherein the electrodes are coated with an electrically insulating material; applying a symmetrically balanced time-varying potential to the electrodes, the potential having a predetermined amplitude; sweeping the potential over a range of frequencies from a first frequency to a second frequency greater than the first frequency; monitoring magnitude of amplitude modulation of the potential over the range of frequencies; and determining the quality of the oil based on variation of the amplitude modulation. A system for practicing the method is also provided.

Abstract: The present invention includes a method of detecting contamination in a fluid sample includes bringing a fluid sample into contact with a pair of spaced apart electrodes and applying a plurality of voltages across the electrodes, wherein the plurality of voltages vary in magnitude between a first and second voltage level. The current is then measured between the electrodes at the plurality of voltages and a contamination level is determined using the measured currents. The present invention also includes a system for determining a particulate contamination level in a fluid sample. The system includes a sensor including a pair of spaced apart electrodes, wherein the fluid sample is brought into contact with the electrodes for detection of the level of particulate contamination therein, and a voltage application means for applying a voltage across the spaced apart electrodes. The system also further includes a current sensor coupled to one of the electrodes.

Abstract: The present invention discloses a method and a sensor (1) for oil-in-water measurement, in particular for the oil industry. In an electric measuring cell (7, 12) a capacitance is measured as a measure of an oil concentration in the water flowing through or in the accumulation filter (16, 16a, 16b). In order to reduce the maintenance requirement, the measuring cell (7, 12) is automatically calibrated at recurring time intervals with clean water (FIG. 1) and/or flushed with water, possibly oil-contaminated, in the back-flushing direction (FIG. 2). Advantages of the invention are, inter alia, reduced signal drift, improved long-term reliability and a long service life without monitoring or filter exchange.

Abstract: Method and device for measuring the resistivity index curve (Ir) of a solid sample such as a geologic sample independently of the capillary pressure curve (Pc). Multi-frequency complex impedance measurements are carried out for a sample subjected to a radial confining pressure, during operations of drainage or imbibition of a first, initially saturating fluid, through a semipermeable membrane permeable to this first fluid, placed at a first end of a containment cell, by injection of a second fluid under pressure at the opposite end thereof. One or more injection pressure stages are applied and the continuous variations of the resistivity index (Ir) as a function of the average saturation (Sw) variation are measured without waiting for the capillary equilibria to be reached. Electrodes pressed against the sample on the periphery thereof are used, these electrodes having a given longitudinal extension in relation to the length of the sample and being connected to an impedance meter.

Abstract: A process for online measurement of electrical conductivity to control minimum conductivity of fluids, especially rolling oil, which prevents charging and discharging, by controlled addition of conductivity additives. The process measures the time change of conductivity to determine the amount of extremely fine particulate fouling and the degree of impurity of the rolling oil. The process also provides online measurement of the dielectric constant and online measurement of permeability.

Abstract: A brake oil detector is disclosed. It includes a housing formed with a through hole on one side, a circuit board disposed in the housing and having a wire extending through the through hole to outer side of the housing, a pivotable rotary shaft disposed in the through hole and an extension arm disposed at one end of the rotary shaft and having a free end disposed with a sensor connected to the circuit board by the wire. The sensor of the extension arm is extended into a brake oil tank to check out the viscosity of the brake oil and judge whether it is necessary to replace the brake oil.

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.

Abstract: A sensor assembly for measuring characteristics of motor oil in a vehicle includes a housing adapted to be mechanically coupled to a vehicle for receiving motor oil of the vehicle and at least one capacitive sensor including sensing electrodes positioned relative to the housing to measure characteristics of motor oil between the sensing electrodes. The sensing electrodes are coated with a soot build-up inhibiting coating which, in a preferred embodiment, is a silicone coating. The at least one capacitive sensor include an oil level sensor and an oil deterioration sensor in a preferred embodiment.

Abstract: A sensor assembly includes a tilt sensor, an oil level sensor, an oil temperature sensor and an oil deterioration sensor, as well as associated output signal conditioning electronics integrated within a common assembly. The sensor assembly is configured to receive a volume of motor oil proportional to a total volume of oil in an engine. The oil level sensor, oil temperature sensor and oil deterioration sensors include electrodes which are completely or partially immersed in the volume of motor oil depending upon the total volume of oil in the engine. The tilt sensor includes only two electrodes both of which are at least partially immersed within a controlled volume of dielectric fluid which is physically and electrically isolated from the volume of motor oil. One of the electrodes of the tilt sensor is completely immersed in the controlled volume of dielectric fluid independent of an angle of the tilt sensor relative to a vector representing forces such as gravity applied to the tilt sensor.

Abstract: The present invention relates to a method and apparatus which can be used to detect the abnormal operating condition of equipment, such as engines and machinery, the usefulness of the fluid, and the content of wear metals and elemental constituents in the fluid. The method comprises the steps of bringing at least two electrodes into contact with a sample of a fluid to be analyzed; applying a square voltage wave form to the electrodes at a predetermined scan range and scan rate to cause a current to flow between the electrodes; monitoring the current at the electrodes to determine a current output signal; using the current output signal to measure the conductivity of the fluid; and analyzing the sample to determine a content of wear metals and elemental constituents in the sample.

Abstract: An apparatus for the detection and identification of metal particles, coolant or water in engine oil or hydraulic fluid. The apparatus comprising means for generating a high frequency oscillating field within the fluid, means for generating an electric field within the fluid, means for measuring the real and imaginary part of the complex impedance associated with the interaction of the electric field and the fluid, and means for determining at least one of the presence, the absence or the variation of metal particles, coolant or water in the fluid based upon the impedance measured. The high frequency oscillating field has a frequency range of approximately 2 megahertz to 10 gigahertz. Also, apparatus for the detection and characteristic identification of contaminants in engine oil or hydraulic fluid is provided.

Abstract: A method is provided for evaluating a multiplicity of lubrication quality parameters. For a particular lubrication system, a parameter profile is designated to define all the measurable parameters to be monitored. Each parameter in the profile is assigned to single category respective to WEAR, CHEMISTRY and CONTAMINATION. Parameter values are proportionalized in a finite number of increments between acceptable and unacceptable limits. The worst case parameter of a category is selected to represent that category on a 3-axis, Cartesian graph for placing a data point along the respective category axis. Three data points respective to the three axes are linked with a triangular plane, the area of which is representative of the system quality state.

Abstract: A materials characterization test cell is disclosed. The test cell includes a housing including spacers for supporting sample insulation materials, and a channel disposed in the housing to permit the passage of oil through the housing. A pair of electrodes is provided to provide a mechanism for making polarization spectrum and/or streaming electrification measurements.

Abstract: Method and apparatus for determining deterioration of e.g. lubricating oil by measuring the electrical properties of a polymeric matrix (support) holding charged ionic groups. The dynamic range of the device is increased by creating a local polar environment formed around the charged groups of the polymeric matrix and by exploiting bead shrinkage with increasing degradation (or solvent polarity). Both approaches can be further employed in a single sensor by the use of multiple chambers containing a combination of the above. Also, contaminant detection is improved by detecting changes in amplitude and/or frequency of noise output. The sensor can also be used to detect a level of oil for instance in an engine oil pan.

Abstract: Method and apparatus for determining deterioration of e.g. lubricating oil by measuring the contraction of a polymeric matrix (support) holding charged ionic groups. The support contracts due to oil quality degradation. The expansion/contraction is detected e.g. electrically.

Abstract: A method and apparatus for determining the condition of a fluid used in a process, such as a lubricating oil used in an internal combustion engine. A sample of the fluid is heated to an elevated temperature, a measurement is taken of an electrical characteristic of the fluid at that first temperature, the fluid is heated still further, and the aforesaid electrical characteristic is measured again. The two measured values of the electrical characteristic are used to calculate a quality parameter which, when compared with quality parameter values corresponding to fluid samples of varying condition, gives an estimate of the relative condition of the fluid sample under test. The test procedure also includes a measurement of the opacity of the fluid sample to visible light, with this measurement being used in conjunction with the calculated quality parameter to more accurately determine the relative condition of the fluid under test.

Abstract: A method for determining the degree of deterioration of oils or fats for deep-frying or frying foods is disclosed. The specific ohmic resistance of the oils or fats is measured and the extent of the fall of this resistance with increasing deep-frying time or frying time is used as a correlation for the degree of deterioration of the oils or fats.

Abstract: A chip detector is an open circuit device that attract metal chips circulating throughout a piece of equipment such as a transmission. If a chip closes the circuit in the chip detector, then it is subjected to a first pulse of energy in an attempt to burn or displace it from the chip detector contacts. The energy content of the first pulse is selected to burn fuzz, which represents chips of an acceptable size. If the chip remains in the chip detector, then it is subjected to one or more additional pulses each having a greater energy content than the first pulse. The number of pulses and their energy contents are recorded to determine the size of the chips captured by the chip detector and to provide a history of the equipment being monitored. If the chip in the chip detector exceeds a predetermined threshold, then an indication is given on a user interface.

Abstract: Apparatus for removing water from a dielectric oil includes first and second spaced-apart electrically conductive walls, a bed of molecular sieves between the first and second walls, and a device for measuring the capacitance across the bed of molecular sieves between the first and second walls.

Abstract: A portable sonic testing device for the testing of waxy and emulsified fluids, utilizing variations in sound wave propogation, light propogation, and changes in electrical resistance in the liquid, all over a range of temperatures and chemical treatment conditions. The patent also discloses equations used to derive additional information from the output of the device.

Abstract: Apparatus which determines the water cut of a sample petroleum stream irradiates the sample stream at two different locations with microwave energy. The distance that the microwave energies pass through the sample stream are also different. A receiver receives the microwave energies and provides corresponding received signals. The water cut is determined in accordance with the received signals.

Abstract: An oil deterioration detector comprising a sensitive electrode whose electric potential varies in response to acidity and/or basicity of oil to be measured, and a reference electrode associated with this sensitive electrode. An electrically conductive housing accommodates the sensitive electrode and the reference electrode together with the oil. A potential difference detector detects oil deterioration by measuring a potential difference between the sensitive electrode and the reference electrode. And, an insulating member is interposed between these electrodes and the electrically conductive housing for electrically insulating these electrodes from the electrically conductive housing. The reference electrode is grounded together with the electrically conductive housing. An insulating, hydrophilic porous member would be interposed between the sensitive electrode and the reference electrode.

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.

Abstract: This invention relates to a sensor for the direct and continuous measurement of the electrochemical properties of compounds in a high resistivity liquid. The sensor has a housing which includes a porous hydrophilic membrane which may be made of a ceramic, and contains an electrolytic solution. The membrane permits the passage of a portion of the electrolytic solution into the pores thereby facilitating the formation of an interface between the electrolytic solution and the high resistivity liquid and allowing extraction of the compounds in the high resistivity liquid into the electrolytic solution. A porous sensing electrode is positioned directly on the membrane for detecting and measuring the concentration of the compounds extracted from the high resistivity fluid.

Abstract: A great many small volume samples are taken, at a high rate of frequency, from a multi-phase fluid stream to determine the respective oil, water and gas fractions. Rapid fluctuations from an all liquid curve will indicate the presence of gas in the fluid.

Abstract: An electrode structure of a metallic particle detecting sensor capable of detecting with high efficiency metal powders floating in a wide range in an oil tank. The electrode structure is formed by opposing, on a substrate, a pair of electrodes (1, 2), formed of thin film metals of such as Ta, W, Pt, Cr, Au or the like, having combed (toothed) structures with their respective teeth being meshed or interdigitated with each other.

Abstract: A method and apparatus for determining the quality of a lubricant by its solvating effect on an insoluble (resin) matrix to which charged groups have been covalently bound. The solvating effects are measured electronically as a variation in conductivity or capacitance of the resin matrix with respect to temperature. The apparatus includes a metal mesh housing containing e.g. milligram amounts of charged resin beads. A metal probe is fitted in the containing mesh and makes contact only with the resin beads. The entire device is immersed in the lubricant and the electrical conductivity or capacitance is measured from the probe to the mesh through the resin beads. Lubricant degradation is measured as e.g. a decrease in electrical conductivity through the resin beads with respect to an increase in the lubricant's solvent polarity.

Abstract: A metal particle detector apparatus for use with flowing non-conductive fluid such as lubrication oil from an engine or other rotary device wherein the lubricated components include bearings or the like susceptible to failure, thereby placing harmful metal particles in the non-conductive fluid. A circuit grid comprising two electrodes affixed on a perforated electrically non-conductive plate which is disposed in the fluid flow in a manner which will catch the particles being carried by the fluid and when one, or an accumulation of these particles bridges the gap between electrodes completes an electrical circuit passing into the device from outside. In one embodiment, a primary and secondary seal are provided for sealing fluid against leaking into the electrical chamber leading to the electrical circuit or alarm system while still permitting the electrical circuit system to be electrically connected to the detector unit which is disposed in the flowing fluid. Compressible O-ring seals are used.

Abstract: A low molecular weight organic liquid detection sensor which is a wire body formed by coating a core material with a conductive layer made of a substantially non-crosslinked material having a Shore A hardness not more than 70 which is mainly composed of thermoplastic elastomer and conductive carbon, the conductive layer varying in its electric resistance upon contact with a low molecular weight organic liquid. The sensor of the invention permits secured mechanical strength, its easy installation in a narrow conduit or over a wide area, and highly sensitive sensing of a low molecular weight organic liquid in the longitudinal direction.

Abstract: The present invention includes a dielectric sensor which provides at least two signals corresponding to the sensed dielectric of a petroleum stream. A temperature sensor also senses the temperature of the petroleum stream and provides a corresponding temperature signal. Crossplot data arrange the two parameters associated with the petroleum stream dielectric is stored in a memory. The memory is accessed using signals from the dielectric sensor and the temperature sensor to select data from the memory. An output circuit provides a water cut signal in accordance with the selected data.

Abstract: A liquid mixing ratio detecting apparatus is designed so that an oscillation voltage generated by an oscillation unit is applied to one of a differentiating circuit and an integrating circuit, which is constituted by a combination of a capacitor composed of a pair of opposite electrodes for detecting a mixing ratio of a mixed liquid and a resistor, and a mixing ratio detecting unit produces a signal relating to an inclination rate of one of a differential waveform signal and an integration waveform signal, which is generated by one of the differentiating circuit and the integrating circuit, respectively, thereby obtaining a signal representing the mixing ratio of the mixed liquid on the basis of the produced signal relating to the inclination rate of the waveform signal.

Abstract: An apparatus and a method for determining the water content of an oil-in-water emulsion is disclosed. The apparatus includes a first sensor for measuring the real part of specific admittance of the emulsion, a second sensor which acts as a temperature compensation device and electronic circuitry for producing a signal representative of the water content of the emulsion. The method for determining the water content comprises measuring the real part of specific admittance of an oil-in-water emulsion and providing a signal representative thereof, providing a reference signal indicative of the emulsion temperature, adjusting the measured real part of specific admittance signal with the reference signal and converting the adjusted signal into a current signal representative of the percentage water content of the emulsion.

Abstract: The conductance meter includes source means which irradiates a fluid with microwave energy. A receiver receives microwave energy that has passed through the fluid and provides the received microwave energy as test microwave energy. Electronic apparatus determines the conductance of the fluid in accordance with the amplitude of the test microwave energy and the phase difference between the microwave energy from the source and the test microwave energy from the receiver where only 1 microwave frequency is used.

Abstract: A device for measuring the concentration of two substances through the transmission of electromagnetic waves. The device utilizes at least one transmission element for transmitting a signal and at least two receiving elements for receiving a signal from the at least one transmission element and providing first and second output signals. The present invention also utilizes a receiving device for receiving the first and second output signals from the at least two receiving elements such that the difference or ratio of the two signals is utilized to determine the concentration.

Abstract: A sensor and system for monitoring the accumulation of contaminants in oil wherein the contaminants have an electrical conductivity which is different from the oil. An electrochemical cell is used to measure the alternating current conductivity of the oil to provide an indication of the amount of contaminants present in the oil. Acids and water are two common engine oil contaminants which are accurately monitored by this alternating current conductivity measurement system.

Abstract: A brake fluid tester for measuring the quality of brake fluid, comprising means for measuring the conductivity of the brake fluid, preferably comprising a plurality of comparators for comparing the resistance of the brake fluid to a plurality of reference, resistances. The device further comprises indicating means, preferably light emitting diodes, responsive to the measuring means for indicating the quality of the brake fluid based upon its measured conductivity. An increasing number of diodes are illuminated as the conductivity of the brake fluid increases, providing a positive indication when the device is working and providing an easy to interpret display of the test results. The diodes are preferably activated at preselected levels of conductivity, corresponding to preselected levels of moisture contamination.

Abstract: A variable mode microwave water cut monitor includes a test cell which contains a fluid sample. Apparatus controls the provision and removal of the fluid sample to effect different modes of operation for the monitor, a normal test mode and at least two calibration modes. A source provides microwave energy to one of a first antenna which in turn provides the fluid sample in the test cell with microwave energy. A second antenna receives the microwave energy that has passed through the fluid sample. A detector detects the received microwave energy and provides a signal corresponding thereto. An indicator provides an indication of the water cut of the fluid sample in accordance with the received signal power, a phase difference between the source provided microwave energy and the received microwave energy and internally recorded calibration data for water alone and oil alone.

Abstract: An arrangement for detecting metallic particles carried by a fluid includes a metallic probe member which surrounds an elongated passage through which the fluid flows and which is constituted by a split tube having two marginal portions delimiting a gap which extends along said passage and completely separates the marginal portions from one another. Capacitors are arranged at the gap and alternating electric current is caused to flow in the probe member around the passage so that the probe member and the capacitors form a tank circuit having resonance characteristics that are influenced by any inclusion then present in the passage in a manner dependent on the electromagnetic properties of the inclusion. The character of any metallic particle then present in the passage is determined from variations in the alternating electric current that reflect the influence of such metallic particle on the resonance characteristics.

Abstract: A method and system for determining fluid saturation within a fracture. The method comprises the steps of establishing a functional relationship between fluid saturation and capacitance for a multiple component fluid; introducing the fluid between the fracture faces of the fractured media; measuring electrical capacitance between the fracture faces; and determining fluid saturation from the capacitance measurement and the functional relationship. The method and system find utility with both simulated and natural fractures.