Abstract: In one aspect of the present invention, an apparatus for detecting particles within a fluid is disclosed. A bobbin defines a debris collection chamber. Spaced apart first and second coils are wound about the bobbin in the proximity of the debris collection chamber, wherein the inductance of the coils are responsive to the particle accumulation within the collection chamber. An electromagnet is wound about the second coil to attract ferrous particles into the proximity of the second coil. A reference coil is wound about the bobbin to compensate for the changing temperature of the fluid. An oscillator is coupled to the first, second and reference coils for selectively producing an oscillating waveform at a frequency that induces eddy currents in the particles. The frequency of the oscillating waveform is indicative of the amount of accumulation of both the ferrous and non-ferrous particles.

Abstract: In one aspect of the present invention, an apparatus for detecting particles within a fluid is disclosed. A bobbin defines a debris collection chamber. A first coil is wound in a helix about the bobbin in the proximity of the debris collection chamber, wherein the induction of the first coil is responsive to the particle accumulation within the collection chamber. A reference coil is wound in a helix about the bobbin to compensate for changing fluid temperature. An oscillator is coupled to the first and reference coils for selectively energizing the coils with an oscillating waveform at a frequency that induces eddy currents in the particles. The frequency of the oscillating waveform is indicative of the amount of accumulation of both the ferrous and nonferrous particles.

Abstract: An apparatus is disclosed for determining the concentration of a fluid. In one aspect of the invention an apparatus for detecting the ionic concentration of a fluid is provided. The ionic concentration detecting apparatus may include a resonance coil or other suitable receiver that arranged to be influence by the fluid being monitored. The resonance coil is driven by a high frequency signal having a frequency in the range of 10-100 MHz. A detector is provided to measure the losses experienced by the resonance coil. In another aspect of the invention, an ultrasonic based density detecting apparatus for detecting the density of the fluid is provided. The ionic concentration detecting device may be used in conjunction with the density determining device to provide concentration detecting capabilities for solutions having multiple constituents.

Abstract: A method and apparatus for investigating various parameters of biofluids, such as blood, particularly protein and cellular concentrations and cellular volume utilises the application of at least two a.c. frequencies, preferably simultaneously, in the range 0.1 to 60 MHz to a sample of the fluid and receiving and resolving the frequencies after passage through the fluid. The received frequencies are processed to derive corresponding d.c. voltage amplitudes which are mathematically processed to provide a numeric output correlating with a parameter under investigation, A new parameter named Instant Sedimentation Rate (ISR) is disclosed.

Abstract: In order to measure the magnetic saturation flux density of a sample material, a first and a second sample holder are symmetrically positioned on the same side of a cylindrical permanent magnet. Coils are placed around the sample holders and the cylindrical permanent magnet is rotated. The signals induced in the coils in the absence of a magnetic material in one of the sample holders are applied to an amplifier in such a manner as to provide a null input signal. When a sample is placed in one of the sample holders, the magnetic saturation flux density can be measured. The present device finds particular application to determining the concentration of a magnetic particles dispersed in a (coating) fluid. The fluid can flow through a sample holder for measurement. In addition, a reference fluid can flow through the second sample holder for better process control. The geometry of the sample holder carrying a fluid material is specified to increase the accuracy of the measurements.

Abstract: In an inductive debris monitor (IDM) an inductive probe is disposed at a fluid flow passageway to be monitored, and an RF bridge containing a variable resistance network is used to detect changes in the impedance of the probe due to the passage of metallic debris. An indirectly heated thermistor is utilized in the resistance network for balancing the bridge. Thus the operating temperature range is significantly extended without compromising reliability or experiencing degradation.

Abstract: In order to measure the magnetic saturation flux density of a sample material, a first and a second sample holder are symmetrically position on either side of a cylindrical permanent magnet. Coils are placed around the sample holders and the permanent magnet is rotated. The signals induced in the coils in the absence of a magnetic material in one of the sample holders are applied to an amplifier/meter in such a manner as to provide a null signal. When a sample is placed in one of the sample holders, the magnetic saturation flux density can be measured. The present device finds particular application to determining the concentration of a magnetic particles dispersed in a fluid.

Abstract: In an apparatus for determining the respective percentages of first and second liquids in a mixture, the apparatus including an inductive coil for immersion in said fluid mixture such that the mixture at least partially determines the value of distributed capacitance exhibited by said coil winding, and including associated circuitry; a housing for encasing the inductive element and associated circuitry.

Abstract: The present invention relates to a method and to a device for testing a partly conductive medium to determine a characteristic thereof. A signal generator generates a periodic excitation signal in a resonant circuit, including a coil which produces a magnetic field, which is coupled to the partially conductive medium. Eddy currents induced in the partially conductive medium cause the current flowing in the resonant circuit to vary. The amplitude of the envelope of the current flowing in the resonant circuit is measured and processed to determine the characteristic of the medium.

Abstract: An apparatus and a method to remove and collect ferrous particles from a fluid for ferrous particle analysis. In one embodiment, the apparatus includes a holder chamber and a removable examination slide within the chamber. A magnet induces a magnetic field at the examination slide. A portion of the fluid is passed over the slide in order for the magnetic field to retain ferrous particles on the slide. Thereafter, the slide can be removed from the holder chamber for ferrographic analysis.

Abstract: A debris detecting apparatus is provided which collects debris from a fluid system in a screen member and measures the accumulation of debris by measuring the change of inductance in a coil surrounding a portion of the screen member. A bridge detection means is used which includes the inductive coil as one leg of the bridge. A second sensor in the fluid connected as a second leg of the bridge provides temperature compensation for the bridge. The bridge is excited with a high frequency voltage at or near the resonant frequency of the sensing coil.

Abstract: In an electrophotographic or electrostatic image forming device, the toner concentration of a two-component developer, i.e., a mixture of toner and carrier is measured on the basis of an output of a magnetic bridge type concentration sensor responsive to the magnetic permeability of the developer. The sensor has a surface whose mean roughness along the center line is less than 0.4 .mu.m Ra.

Abstract: A method and apparatus is provided to prepare samples of viscous industrial fluids such as machine lubrication oil for analysis for the presence of magnetically responsive particles and other suspended solids. A test sample of the fluid is held in non-magnetic vessel. This sample holding vessel is positioned in the cooperative pocket of a portable, handheld vibrator and stimulated by 120 to 150 Hz, vibration for a designated period of time, usually 30 to 60 seconds. A strong permanent magnet below the vibrating vessel pocket is oriented to emit a magnetic field on or within the sample simultaneously with the vibrations to induce rapid settlement of any magnetic particles toward the vessel bottom. Such vibration also assists and accelerates pure gravity settlement of non-magnetic particles. Entrained gas bubbles tend to rise more rapidly to the sample surface due to the vibrational stimulation.

Abstract: In one aspect of the present invention, a sensor detects particles within a fluid. The sensor includes a housing that defines a cavity. A magnet is disposed adjacent the cavity bottom to attract particles into the cavity. A first coil is wound about the outer surface of the cavity. The induction of the first coil is responsive to the particle accumulation within the cavity. A second coil is wound about the magnet. The induction of the second coil is responsive to the temperature of the fluid and independent to the particle accumulation within the cavity.

Abstract: An apparatus for determining the paramagnetic characteristics of substances such as oxygen includes a cuvette rotating in a magnetic field. The cuvette includes measuring chambers and reference chambers and an alternating voltage is induced in the measuring field coils by the rotation of the cuvette along the magnetic field. A base signal disturbing the measuring signal is also generated. This base signal is caused primarily by changes in the thickness of the material in the reference chambers and the measuring chambers and/or by material thickness changes of the cuvette. To eliminate this base signal, the cuvette includes a magnetic compensating device. This device is mounted at such a position that it generates a compensating magnetic field during its rotation through the magnetic field. This compensating field generates a compensating voltage which has the same amplitude as the base signal but has a signal waveform which is opposite in phase to the base signal.

Abstract: A system for sensing metallic debris in fluid flow, including an inductive probe utilizing one or more capacitors with a single turn resonant coil disposed about the flow passageway wherein a second, co-linear, multiple turn coil is provided about the passageway and loosely coupled via mutual inductance to the resonant coil such that the two windings produce a step-up transformer with increased impedance to closely match the impedance of the electrical output cable. This impedance matching reduces output signal loss permitting the sensitive components of the system to be remotely located from the usually hostile environment of the probe. Additionally, a toroid element of low loss, low reluctance material is disposed between the probe and its conductive housing to provide a guiding path for the magnetic "lines of force" of the sensing field produced by the probe, to avoid losses in the housing.

Abstract: A device to detect the presence of particles, principally metallic particles, in fluid lines. The fluid to be sampled flows through a former on which is wound a coil assembly comprising a sensor coil flanked upstream and downstream by two field coils. The former is constructed with a double wall and air gap such that pressure fluctuations in the fluid are not transmitted to the coil assembly to adversely affect the positions and readings of the coils. The field coils are driven by a high frequency signal derived from a crystal oscillator and the upstream and downstream sections are wound in opposite directions such that the magnetic field from each section is cancelled out in the plane of the sense coil.

Abstract: Wear particle monitoring is carried out on samples of a lubricating oil extracted from lubricated equipment together with the naturally appearing burden of ferromagnetic particles. The extracted sample is collected in a bottle to a depth sufficient to exceed the flux field of a sensing coil to which the bottle is subsequently applied whereby the numerical value (PQ value) assigned to the particle burden is substantially insensitive of the volume of liquid in the bottle. From time dependent measurements information as to the size of the particles in the burden can be obtained.

Abstract: The invention is directed to an apparatus for determining the component of paramagnetic substances such as oxygen. This determination is made with a magnetic field source and an even number arrangement of magnetic field cores, with each field core being surrounded by a measuring field coil for detecting the magnetic changing field generated by a rotatable cuvette. The apparatus is improved in that the formation of the magnetic stray fields is reduced and the component of the magnetic flux which is effective for measurement and which passes through the cuvette is increased. For this purpose, the cuvette is mounted in the housing of the apparatus in such a manner that its rotational plane partitions the housing into two component regions. The magnetic field source is arranged in one component region and the magnetic field cores and the measuring field coils corresponding thereto are arranged in the other component region of the housing.

Abstract: An electrical magnetic detector disposed in the passage of a flow of fluid to detect the magnetic particles transported by that flow and to trigger an alarm after detection of a predetermined quantity of magnetic particles. It includes a magnet surrounded by two polar masses separated by an axial air gap. The external surface of the detector has, at least adjacent the air gap (4), peripheral surfaces (5, 6) converging toward the air gap. The detector is useful in the surveillance of wear members to detect the degree of wear thereof.

Abstract: A method and apparatus for determining the proportion of a paramagnetic gas in a mixture of gases is disclosed. There is provided an element which is able to oscillate in a magnetic field. A force acting on the element due to the presence of paramagnetic gas in the magnetic field changes according to the concentration of paramagnetic gas present. This change in force affects parameters of the oscillation such as damping and frequency, which may be monitored thereby to determine the concentration of paramagnetic gas present.

Abstract: An inductive debris monitor for detecting chip-particles in tubing of a fluid wetted system. The inductive debris monitor includes a multi-turn detector and an electronic circuit having a resistor bridge configuration. The multi-turn probe detector wraps around the tubing of a fluid wetted system a plurality of times to detect the presence of the chip-particles while the electronic circuit analyzes and deciphers the detected chip-particle information.

Abstract: In an improved electromagnetic induction-type conductivity meter utilizing primary and secondary transformer coils about a liquid sample passageway, a resistance circuit having a conductive lead line extending also through the coils and parallel with the sample passageway is provided. The resistance circuit can be selectively opened and closed, and has the capacity to contribute to the measurement voltage detected on the detector coil when the primary coil is excited. The value of this additional resistance voltage can be used for calibration and monitoring the condition of the conductivity meter.

Abstract: A magnetic sensor for the collection and measurement of ferrous particles through the use of an electronic tuned circuit is disclosed. The sensor contains an electrical inductance coil along with an integral magnet to attract ferrous particles suspended in the fluid. The ferrous particles collecting on the magnetic surface of the sensor causes a change in the inductance of the integral coil which is measured by an electronic circuit. The electronic circuit operating in conjunction with the sensor utilizes a series resonant circuit. A measurement of the voltage across the series resonant circuit is responsive to changes in temperature of the inductance coil. A microprocessor is used to determine the change in period of the resonant oscillation with change in inductance of the coil. The microprocessor uses the data on temperature variation to correct the observed change in oscillator period for the effects of temperature.

Abstract: A method for monitoring the environment of a vessel provides a liquid (18) which may contain particles (20) in a vessel having containment walls (12), where a hollow member (26) such as a thin tube is inserted into the liquid near the containment walls, and the hollow member contains in it a robotic device (34), which can travel within the hollow member and which can emit and receive ultrasonic waves and electromagnetic fields, where both of the ultrasonic waves and electric fields can pass through the hollow member (26) to the containment walls (12), where the device: emits and receives low frequency ultrasonic waves to and from the containment walls (12) and high frequency ultrasonic waves to and from any particles (20), and emits electromagnetic fields to the containment walls (12) or their combination, where absorptions and reflections from the hollow member walls and the containment walls, and any particles present are measured and any current generated in the hollow member walls and the containment wall

Abstract: A device to detect the presence of particles, principally metallic particles, in fluid lines. The fluid to be sampled flows through a sensor coil which is flanked upstream and downstream by two field coils. The field coils are driven by a high frequency signal derived from a crystal oscillator and the upstream and downstream sections are wound in opposite directions such that the magnetic field from each section is cancelled out in the plane of the sense coil. When a ferromagnetic or conductive particle passes through the winding structure, the coupling in the sense coil is disturbed as the particle first interacts with the field in the upstream section of the field coil and later with the field in the downstream section of the field coil as it passes through the Sensor Coil Assembly (SCA). A characteristic signature is generated in the sense coil which results from the vector summation of these transient imbalance signals with the steady-state signal from the opposed field coils.

Abstract: A powder capsule loading system and apparatus for preparing and loading a gelatin capsule with a powder product for testing of the product in a magnetometer. The system includes a gelatin capsule which is readily available, such as those used in the pharmaceutical industry, and a sample tool including a handle section and a cup section which includes an aperture sized to receive part of a capsule portion and holds the capsule portion therein by friction fit. Initially, a top portion of the capsule and a bottom portion of the capsule are each received and held on different sample tools. The capsule portions received within the sample tools are dipped into a sample container of powder product to fill the respective portions with the powder product, followed by assembly of the capsule. The assembled capsule containing a substantially predetermined amount of powder therein is then weighed.

Abstract: A zero compensation circuit particularly is used in an oxygen sensing apparatus and method employing a sensing cell including two pairs thermistors and a source of an inhomogenous magnetic field. One thermistor of each pair is electrically heated and is positioned inside the magnetic field, and the second thermistor of each pair is positioned adjacent to the respective first thermistor of each pair, substantially outside the magnetic field. When oxygen is present in the sensing cell, the thermistors inside the magnetic field generate a gas flow in the direction of the adjacent thermistors of each pair positioned outside the magnetic field, thus tending to reduce the temperature of the thermistors inside the field and increase the temperature of the thermistors outside the field.

Abstract: An apparatus and method for the in-situ measurement and prediction of the onset of hypoxic conditions in aquatic media is disclosed. The apparatus includes a magnet and sensor for concentrating and measuring biogenic magnetic fields produced by ambient populations of microaerophilic magnetotactic bacteria in aquatic sedimentary environments and means for correlating the measured data with oxygen content in the locations monitored.

Abstract: A simpler, multiple element chip detector having two parallel, electrical conductors shrouding a plurality of discrete magnets which are aligned along the longitudinal axis of the chip detector is provided. The poles of each magnet abut opposite conductors defining a chip gap. A plurality of electrical isolators are mounted about the conductors and positioned between each of the magnets to define a chip element therebetween. The number of chip elements can be varied by adding or subtracting a magnet and isolator. The conductors are mounted in a housing to receive an electrical potential. Thus, regardless of the number of chip elements no additional circuitry is required. In an alternative embodiment the discrete magnets are replaced with a single magnet. In this embodiment the number of chip elements can be increased or decreased by only adding or removing an isolator.

Abstract: An apparatus for detecting the degree of deterioration in lubricating oil including a grid-like capacitive sensor, that uses the lubricating oil as a dielectric medium, and a magnetic field imposed upon the oil to attract ferromagnetic wear particles into the vicinity of the sensor. Preferably, the magnetic field is generated by a permanent magnet and an electromagnetic aligned such that the magnetic field produced by each magnet acts upon the oil along the same axis.

Abstract: An improved detector assembly with an electromagnetic induction-type conductivity meter is provided with a pair of housing members forming a first liquid sample flow path at a central location, and a second liquid sample flow path on their outer circumference. An excitation coil and a detection coil extend about the first liquid sample path, while the second liquid sample flow path interconnects with the first liquid sample flow path both upstream and downstream of the respective coils. The second liquid sample flow path can substantially extend about the coils so that a relatively large induction current can be generated and measured as representative of the liquid sample.

Abstract: Nonintrusive sensors capable of measuring various storage cell parameters such as voltage, state-of-charge, electrolyte level, internal resistance, and temperature are attached to a monitoring module which gathers and processes signals representative of information concerning the condition of electrolytic storage cells and transmits the information to a central computer for further processing. In response to commands issued by the central computer, appropriate maintenance and/or repair operations can be initiated. Alternatively, the system described can be used to automatically perform such maintenance tasks as checking and adding electrolyte levels, reducing the voltage in cells whose output voltage is too high, and leveling the state-of-charge of each cell in an array of electrolytic storage cells. The system can monitor other functions of the electrolytic storage cells, including the evolution of hydrogen gas and the accumulation of sediments in individual electrolytic storage cells.

Abstract: A debris monitor apparatus and method and optical sensor apparatus and method that use the Faraday Effect to detect accumulation of debris on a magnetic probe. The probe contains a magnet and the optical sensor and is immersible in the fluid. As debris accumulates on the probe, the magnetic field changes. The optical sensor includes a magneto-optic material located within a portion of the changeable magnetic field, preferably near a node of the magnet. Means are provided to bi-directionally address the sensor magneto-optic material with linearly polarized light. Means are also provided to convert rotation of the light polarization angle into a modulation of the light's intensity. An electro-optic transducer converts the light intensity into electrical signals that indicate the quantity of debris accumulation on the probe, with a differentiated value of these signals with respect to time yielding rate of debris accumulation on the probe.

Abstract: An apparatus is adapted to detect particles within a fluid. The apparatus includes first and second electrodes within a housing. The first and second electrodes form a "V" shaped recess. A magnet is positioned within the housing to attract ferrous particles into the recess. The resistance between the first and second electrodes is measured as an indication of particles within the fluid.

Abstract: An electrodeless conductivity measuring cell having three toroids. In one arrangement, the three toroids are stacked together wherein the center toroid is used for sensing and the two outer toroids are the drive toroids. Alternatively, the center toroid may be used as the drive coil and the outer toroids used as sense coils. Washer-shaped, grounded discs are placed between the outer toroids and the center toroid to provide for improved noise rejection. A method of validating the fluid conductivity measurement of such a measuring cell. The fluid conductivity is measured with a three-cell configuration, and then it is measured with a two-cell configuration. If the conductivity is observed to be the same, the cells are likely functioning normally. If fluid leaks into the cell cavity, the measurement of conductivity will change.

Abstract: An inductive coil shaped screen traps debris in a fluid and senses the accumulation of the debris. The shaped screen coil comprises non-conductive wires parallel to one another and at least one conductive wire coil perpendicular and woven with the non-conductive wires. The conductive wire is a coil of an inductor. As debris accumulates within the coil, inductance immediately changes and indicates the accumulation of debris in the screen. Another coil connects with the first coil in a bridge circuit to compensate for changes in temperature of the fluid.

Abstract: An electromagnetic conductivity meter comprises a core; a primary coil wound around the core; an alternating power source for applying an alternating voltage having a given frequency to the primary coil to excite the core; a tube wound around the core through which a liquid to be measured flows; induction current detecting means disposed at the opposite ends of tube; and an operational means for determining the conductivity of the liquid to be measured from a value of the induction current detected by the induction current detection means.

Abstract: An inductive conductivity sensor is immersed in a liquid to measure its conductivity. The sensor comprises a transducer for generating a changing magnetic field and for inductively measuring an electric current induced in the liquid by the changing magnetic field. The transducer has an external surface facing the liquid. A elastic membrane separates the external surface from the liquid. The elastic membrane is periodically inflated and deflated to deform its outer shape and thereby remove deposits formed on the membrane.

Abstract: A diagnostic filter device for monitoring electrically conductive and semiconductive particles entrained by a fluid, composed of:a filter element (4) disposed to receive the fluid and to permit passage of the fluid while retaining particles entrained in the fluid;a component (8) disposed for producing an alternating electromagnetic field which extends across at least one region of the filter element (4); andan eddy current detecting instrument (12) connected to the electromagnetic field producing component (8) for detecting the influence on the field of particles in the filter element region.

Abstract: A method for contactless measuring the values of magnitudes which relate to an electrically conductive material in solid or liquid form, for instance such magnitudes as the distance of the conductive material from a given point, linear dimension(s) of a body that incorporates such material, the electrical conductivity value of the material, and the temperature of the material. In accordance with the method, an electromagnetic field, generated with the aid of a constant current which flows through at least one field generating coil, is caused to penetrate at least partially into the material. The supply of current to the at least one coil is discontinued subsequent to the magnetic field having penetrated the electrically conductive material to an extent sufficient for the intended magnitude to be measured.

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 particle sensor having a magnet for attracting and retaining metallic particles in a lubricating fluid is disclosed having a sensor to determine when the particles attracted and retained on the magnet have reached a predetermined level and to transmit this information to a machine operator. The sensor, which includes a plug removably attached to the machine casing, has a magnet which extends into the path of the lubricating fluid to attract and retain metallic particles. A pair of coils, one attached to the moveable plug and one attached to the casing adjacent to the plug are inductively coupled such that the accumulation of particles on the magnet changes the inductance of the coils. An electronic circuit converts the changes in inductance to voltage changes to activate an alarm or other signal to the operator when the threshold value has been reached.

Abstract: Apparatus for measuring concentration of a paramagnetic gas in a gas mixture includes first and second magnet pole pieces positioned adjacent each other with a selected gap therebetween, for generating an inhomogeneous magnetic field. The pole pieces have a selected sectional shape, and a gap-facing surface with a selected configuration, that provide an elongated region of maximum magnetic field intensity in the gap. Electrically heated magnetic wind generating thermistors are positioned in the gap. Electrically heated magnetic wind sensing thermistors are positioned adjacent to the magnetic wind generating thermistors, proximate to the elongated region of maximum magnetic field intensity, such that a heated region associated with the wind generating and wind sensing thermistors is substantially encompassed by the elongated region of maximum magnetic field intensity.

Abstract: An apparatus for detecting magnetic particles suspended in a liquid, such as particles suspended in lubricating oil flowing through an engine. The oil is caused to pass through the area coupling two or more coils while the mutual inductance of the coils is monitored. When a magnetic particle enters the area coupling the coils, the mutual inductance of the coils will increase, thereby indicating the presence of the particle.

Abstract: A gas testing apparatus comprising a body (13, 14) defining a chamber (7), means (2, 3) for creating a magnetic field within the chamber in a first direction, a test body (20), means (19) for mounting the test body (20) for rotation about an axis parallel to the direction of the magnetic field, and gas inlet (9) and outlet (10) means for allowing gas flow through the chamber (7), characterised in that the gas inlet means (9) are arranged and disposed to supply gas to the chamber from two positions at opposite sides of the chamber whereby gas flow from each of the two positions will be parallel to the direction of the magnetic field but in opposition in order to minimize errors resulting from gas flow upon the test body. The chamber is of small volume i.e. less than 0.6 ml which enables the apparatus to be used for preliminary monitoring.

Abstract: In a screened inductance sensor having a drive winding, a sense winding, and a conductive screen for varying the induced voltage in the sense winding by reason of the eddy currents generated in the conductive screen in the presence of the drive field, a physical barrier is interposed between the region of the sensor in the windings are located and the region in which the screen is located. These regions are fully environmentally isolated from each other by the physical barrier. The construction is especially suited to screened inductance level gauges, in particular for fuel tanks, where the conductive screen is part of a float assembly in contact with the fuel, but the electrical windings are kept dry in a separate portion of the gauge.

Abstract: A paramagnetic gas measuring device/instrument including an infrared radiator for irradiating diamagnetic members of the device and for creating a climate within a measuring chamber suitable to evaporate moisture from the members and a gas being analyzed.

Abstract: An imaging system wherein the subject or patient to be examined is placed in a uniform constant magnetic field which is movable over the patient. A secondary magnetic field is generated by paramagnetic substances within the subject when located within the constant magnetic field. In a human body, the primary paramagnetic substance is deoxygenated blood, whereupon the presence of deoxygenated blood in the constant magnetic field produces the above-mentioned secondary field. The secondary field is detected by a two-dimensional array of magnetic field detectors, in close proximity with the patient, mechanically moved simultaneously with the source of primary magnetic field through a region, whose resulting electrical signals are received and processed by an array processor which operates to provide a reconstructed three-dimensional image. In the preferred embodiment as a medical scanner, the present invention provides three-dimensional imaging of arterial and venous blood throughout the human body.

Abstract: The invention is directed to an apparatus for determining the proportion of substances having paramagnetic characteristics, such as oxygen, in a mixture of substances. The apparatus has a housing and the mixture of substances is passed along an arrangement of four magnetic field sources by a rotatable cuvette arrangement mounted in the housing. The apparatus is improved in that the effect of external disturbing influences on the penetration of the cuvette by the magnetic field is reduced and so that the measuring characteristics are independent of the position of the plurality of magnetic field generating units. For this purpose, the arrangement of the magnetic field sources is simply disposed at one side of the housing lying opposite to the rotating surface of the cuvette arrangement facing toward the drive shaft. The arrangement of magnetic field sources includes a carrier plate on which the magnetic field sources are accommodated and carry respective measuring field coils.