Abstract: A powdered toner mixture comprising a non-magnetic toner component and a ferromagnetic carrier component is caused to flow downwardly through a vertical conduit by gravity. An electromagnetic coil is wound around the conduit and energized with an alternating electric signal. An electrically conductive and magnetic mass is disposed inside the conduit. The permeability of the toner mixture decreases as the toner density, or the ratio of the toner component to the carrier component, increases. The lower the permeability of the toner mixture, the greater the proportion of magnetic flux passing through the mass. The flux passing through the mass induces eddy currents therein which, in combination with hysterisis and skin effect losses, dissipate a portion of the electric signal. The amount of power dissipation is a function of the relative proportion of flux through the mass and thereby the toner density and, when measured, provides a measure of the toner density.

Abstract: A furnace operation system, comprising, a plurality of hollow tubes arranged in place at a position lower than the raw material charging level in the furnace, and running through the body of the furnace, said hollow tubes being arranged in place into a multi-stage shape; a plurality of magnetic sensors arranged for each and every one of a designated number of measuring points selected in a manner of corresponding to the hollow tubes in the vertical direction, within the interior of the plurality of hollow tubes; and a means electrically connected with the plurality of magnetic sensors, which conducts processing of said signals from the said magnetic sensors which are obtained in correspondence to the downward movement of the charge fed into the furnace.

Abstract: A method for deriving the eddy current signature of a flaw in a tube proximate a contiguous member which is obscured in the composite signature of the flaw and contiguous member by subtracting from the composite signature a reference eddy current signature generated by a facsimile of the tube and contiguous member.

Abstract: An electromagnetic flaw detection system and method having automatic dynamic error balancing is disclosed.The system includes means for producing an alternating electromagnetic field and for passing a metallic workpiece to be tested along a path through the field. A differential detection coil is disposed in the field near the workpiece path. The coil responds to nonuniformities in the field caused by workpiece flaws, such as voids, to produce flaw indications. Detection circuitry actuates alarm apparatus in response to the flaw indications to further indicate need for corrective action.Automatic balancing circuitry compensates for an error signal, which the differential coil generates due to minute undesired assymmetries in the coil's mechanical structure. The balancing circuitry includes means for generating a reference signal. The reference signal is continually adjusted, in response to characteristics of the error signal, to exactly counterbalance the error signal in phase and amplitude.

Abstract: A tachometer circuit for an engine having an alternator driven capacitive discharge ignition system functions as a frequency-to-current converter converting each ignition capacitor discharge into a precisely controlled amount of electric charge, which is then passed thru an indicating microammeter movement graduated in RPM. The precisely controlled electric charge is developed in a charge transfer capacitor, with the peak voltage appearing across the capacitor being regulated by a programmable transistorized voltage regulator. The temperature coefficient of the charge transfer capacitance is neutralized by the temperature coefficient of the voltage regulator, such that the product of capacitance multiplied by voltage--which is equivalent to charge--remains constant. The precisely controlled charge is initially established by machine trimming of a voltage--determining resistor in the voltage regulator, thereby allowing practical large volume manufacture of the circuit from unmatched components.

Abstract: A capacitive gauging apparatus in which a single central processing unit is connected to a plurality of gauging heads each gauging head having a further plurality of gauging probes. The system then multiplexes the probes and heads to enable the central processing unit to receive serially the output from each of the heads and produce an analog or digital signal which indicates distance between each of the probes and the work piece. A central microprocessor transforms these signals into an output for visual display or calculates the difference between these signals and an ideal master work piece. Further, a highly temperature stable, low capacitance, high impedance amplifier is used in conjunction with each of the probes so that the output signal from each of the probes is stable and accurate over a wide range of conditions.

Abstract: DC magnetizing pulses produce unidirectional flux in the object under test, advantageously into the saturation region thereof. The DC pulses have, or are accompanied by, an AC component for producing eddy currents in the object, and variations in the eddy currents are sensed and used to produce corresponding signals. In a preferred embodiment composite DC pulses having a relatively broad initial value followed by shorter DC pulses are intermittently applied to a primary coil wound around the core of a probe adapted to be inserted into a tube in situ. Small null coils provide an output signal. Quadrature detection and gating means yield outputs corresponding to sufficient saturation of an object, and free from transients due to the intermittent bursts of pulses. Flaw detector and comparator type apparatus are described, including bridge configurations in which the AC component is applied to the bridge.

Abstract: A device for determining the blood sedimentation rate in a substantially vertical test tube, where the electrical or magnetic property of a given volume of liquid, which is changed by the settling of the erythrocytes in the test tube is measured as a function of time, by means of an oscillator with an output circuit which is completed via the column of liquid to be measured and by means of a measured-value pickup, having an output signal of which a pulse sequence of a definite frequency can be fed to a pulse counter with an indicating device.A coil-capacitor resonant circuit is coupled inductively with its coil or capacitively with its capacitor to liquid at a definite height in the test tube. An additional coil inductively coupled to the resonant-circuit coil serves as the measuring pickup. A retuning circuit is provided for the retuning of the resonance of the tuned L-C circuit which is detuned by the lowering of the boundary layer between the erythrocyte column and the plasma in the test tube.

Abstract: In detecting the presence or absence of a developing agent or determining the residual amount thereof, at least one coil is arranged outside a developing agent container, so that a change in magnetic permeability caused by the presence or absence of a developing agent within the container or a change in the amount thereof can be detected as a change in the inductance of the coil.

Abstract: What is disclosed is an apparatus for measuring the relative magnetic field strength of magnetic workpieces such as miniature permanent magnet rotors which, for example, are included in miniature watch motors. The apparatus includes a nonmagnetic shaft member, one end of which is attached to a motor and the other end being positioned in a bearing. The shaft has a reduced portion thereof extending beyond the bearing and located between the poles of an electromagnet which acts as a miniature alternator. Located in the end of the shaft opposite the motor, are inserts for receiving the magnetic workpiece which may be a basic rotor or a rotor/axle assembly. The shaft is rotated at a speed which produces an alternating magnetic field in the electromagnetic pole pieces thus generating an alternating current voltage. This voltage is measured on a digital volt meter or the like with maximum and minimal levels established by calibrating with good and average rotors.

Abstract: An optical null detector design achieves exceptional efficiency of light utilization with a minimum of components providing (1) extremely sharp null recognition, (2) superior long term stability, (3) extremely low power requirement, and (4) minimal size and weight as well as several other desirable properties.The device involves the use of an inherently directional light emitting pattern (DLEP) of optimized geometry, generating nearly all usable light and eliminating several components functionally necessary, though performance limiting in conventional devices. It is particularly suited, though not restricted, to measurement and control applications by means of feedback techniques when high resolution, large dynamic range, and space economy are required simultaneously with sustained effectiveness over long periods of time.

Abstract: Apparatus for locating the position of at least one magnetic member relative to a nonmagnetic member includes a probe assembly movably disposed within the nonmagnetic member and including a nonmagnetic head having a pair of spaced permanent magnets mounted thereon. Each magnet has a variable resistor connected thereto, the resistance of each resistor varying directly with the strength of the flux field emanating from each magnet. The resistors are connected to a source of electrical energy for providing an electrical control signal, the magnitude of which varies in response to the movement of the probe assembly including the magnets and resistors relative to the magnetic member.

Abstract: A pair of similar oscillators are coupled to each other such that when their natural resonant frequencies are close together they lock in and operate as synchronized oscillators over a predetermined range which can be selected by control of circuit parameters. Within the range where the oscillators are locked to be equal in frequency the phase angle between the frequency generated in each oscillator can be used as a measure of the influence on the resonant frequency of one oscillator relative to the other and where this influence is due to the parameters of an external test piece or the like influencing one oscillator, the measurement of phase angle is a measurement of a characteristic or parameter of the test piece.

Abstract: A digital hourmeter-tachometer for use with internal combustion engines or the like comprises a programmable timer for outputting system timing pulses when a d.c. power source is applied thereto. A pick-up pulse circuit generates pulses indicative of the angular speed of the device being monitored and outputs d.c. power to the remainder of the hourmeter-tachometer. A first multiple decade counter counts hour pulses outputted by the timer. A second multiple decade counter counts pulses indicative of angular speed. Display means sequentially display the output of the stored count in the first and second multiple decade counters in response to system timing pulses. A long-life battery applies a direct current to the first counter when the pulses are not received by the pick-up circuit for providing a d.c. source thereby holding the hour count. Preferably, an overspeed shut-down circuit is integrated with the above described circuit.

Abstract: A rotational position detecting apparatus for use in spark ignition control systems for internal combustion engines. A plurality of angular informations are provided circularly on a rotatable disk except at the predetermined reference angular position of said rotatable disk. Two of the angular informations provided beside the reference angular position are spaced twice as wide as a predetermined angular interval between other two of the angular informations. A first and second signal generators spaced integer times as wide as the predetermined angular interval from each other are associated with the rotatable disk for generating respective a.c. output signals in response to the passing of each of said angular informations. The a.c. output signals of the first and second signal generators are applied to an electric circuit which subtracts one of the a.c. output signals from the other of the a.c. output signals and shapes the subtraction resultant signal into a pulse signal.

Abstract: This specification discloses an apparatus and method for providing electrically distinguishable signals occurring as a function of the position of a moving element. It is possible to identify a sub group of electrical signals from the remaining electrical signals or from the entire group. The electrical signals can be used altogether to determine a variable such as revolutions per minute of the movable element or, particular ones of the electrically distinguishable signals can be used for initiating a function such as the firing of spark plugs.

Abstract: A sensor-recorder for recording a representation of the direction and peak amplitude of a transient current. A magnetic thin film is coated on a glass substrate under the influence of a magnetic field so that the finished film is magnetically uniaxial and anisotropic. The film is split into two oppositely magnetized contiguous domains with a central boundary by subjecting adjacent portions of the film simultaneously to magnetic fields that are opposed 180.degree.. With the split-domain sensor-recorder placed with the film plane and domain boundary either perpendicular or parallel to the expected conductive path of a transient current, the occurrence of the transient causes switching of a portion of one domain to the direction of the other domain. The amount of the switched domain portion is indicative of the amplitude of the peak current of the transient, while the particular domain that is switched is indicative of the direction of the current.

Abstract: A large scale integrated circuit with external integral access test circuitry having a semiconductor body with a surface. A large scale integrated circuit is formed in the semiconductor body through the surface and comprises a large number of interconnected circuit elements with a large number of input and output pads connected to the circuit elements and disposed near the outer perimeter of the semiconductor body. An integrated test circuit is formed in the semiconductor body and extends through the surface. The integrated test circuit has a plurality of probe pads carried by the semiconductor body and connected to the test circuit. The integrated test circuit is formed external of but in relatively close proximity to the large scale integrated circuit.

Abstract: A method of determining average speed of a cyclically loaded rotating shaft, and an electronic tachometer for practicing the method. The revolutions of the shaft are counted electronically, a highly time-regular pulse stream is provided, and simultaneously with the counting of the shaft revolutions, the number of pulses in the pulse stream is counted over a time span of between 2 and 120 seconds. Then, the number of revolutions counted is electronically divided by the number of time pulses counted during the time span of 2 to 120 seconds to determine average speed, the speed so determined is digitally displayed, and the revolution and time pulse counting cycles are restarted. The accuracy of the average speed displayed is .+-.0.05%.+-.1 count when the time span is 2 seconds, with a resolution of 0.1 rpm.

Abstract: A modular test tray is comprised of individual modules solidly detachably secured together and shorting straps for rapid and easy electrical connection between modules. Each module is comprised of two tuning fork shaped connector pins embedded in the module and capable of detachable mechanical and electrical engagement with the shorting straps. Two posts capable of receiving electrical components to be tested are also embedded in the module and electrically connected to the connector pins. The posts protrude from the top of the module while the connector pins are recessed in grooves on the bottom of the module. Shorting straps consisting of intermittent strips of electrical conducting material, the strips being of sufficient length to electrically connect only two connector pins of adjoining modules and spaced apart so as to electrically connect consecutive pairs of connector pins, allows a series electrical connection of the components to be tested.