Abstract: A method and apparatus for measuring sheet resistance and thickness of thin films and substrates. A four-point probe assembly engages the surface of a film on a substrate, and the thickness of the substrate is determined from the point of contact between the probes and film. A measuring apparatus then outputs a voltage waveform which applies a voltage to probes of the probe assembly. An inverter inverts the voltage and provides the inverted voltage on another probe of the probe assembly, thus inducing a current in these probes of the four point probe and through the surface of the film. Two other probes measure a voltage in the film created by the current. The voltages on the current probes provide a voltage close to zero at the other probes, thus allowing these other probes to measure voltages with greater precision. The current created by the voltage waveform and the voltage created across the inner probes are measured for each voltage level of the waveform.

Abstract: A fault detecting circuit for use with an electromagnetic acoustic transducer having an electrostatic shield and a wear surface for determining when the wear surface for contacting test surfaces has developed holes.

Abstract: A voltage follower is incorporated within a molded electrical connector interface of a position sensor in a way that does not detract from the dimensions or the performance of the finished sensor. The incorporation of the voltage follower into the housing of the variable resistor provides several advantages over the prior art, including: an immunity to sag; substantially reduced sensitivity to noisy contactors; and short lead length and low output impedance, both of which result in reduced interference from external source.

Abstract: An electric rotating machine comprises a rotor body of cylindrical structure and a stator body covering an outer peripheral portion of the rotor body in a non-contact fashion. The stator body includes a stator winding formed with an insulation layer and arranged radially outward of the rotor body with a clearance from the rotor body and a stator core which supports the stator winding.

Abstract: There is provided a system and method for locating faults in power distribution systems with complex topology, such as multi-phase urban networks (6), utilizing reliable time-delay techniques as well as a transponder (22) at a monitoring point to sense the arrival of the transient fault pulse and for transmitting a timing pulse a known time delay after sensing the arrival of the transient fault pulse and a calibration pulse a known time delay after transmitting the timing pulse. Installed along the power distribution system at key locations are receiver stations (4, 4a, 4b) capable of sensing the arrival of the transient fault pulse, timing pulse and calibration pulse and measuring the time intervals occurring between each. The location of the fault is then determined based on these timing intervals, known time delays and the known propagation velocity of the electric power cables in the power distribution system.

Abstract: A system for automatically detecting whether a power converter or inverter is correctly connected to a three-phase AC power source consisting of first, second, and third phases, the system comprising: a zero-crossing comparator (1) for determining whether the phase of the first-phase voltage (current) is in a positive half cycle or a negative half cycle and generating a first discrimination signal (C.sub.U); a zero-crossing comparator (2, 3) for determining whether the phase of the second- or third-phase voltages (current) is in a positive half cycle or a negative half cycle and generating a second discrimination signal (C.sub.V or C.sub.W); and a D-type flip-flop (5) which detects, in response to the first discrimination signal, that the second discrimination signal is in a predetermined half cycle.

Abstract: A fault indicator is described having a winding disposed on a magnetic pole assembly. The winding delivers energy from a monitored conductor to circuitry of the fault indicator. A series-connected threshold device, such as a four layer bilateral diode or a zener diode, precludes a capacitor from charging during normal current flow in the monitored conductor. The series-connected threshold device, however, breaks down when a fault current flows in the monitored conductor. After break down, the fault current charges the capacitor. A shunt-connected threshold device, such as a zener diode, limits the voltage developed across the capacitor. After its charging phase, the capacitor drives a multivibrator which actuates an LCD, displaying the occurrence of the fault current to an operator. A series-connected threshold device shuts the LCD off when the voltage across the capacitor drops to a sufficiently low level.

Abstract: A device for diagnosing the state of health of an ignition system is provided, where the system includes at least one spark producing channel comprising an exciter, output circuit and igniter plug. The device provides a diagnosis of the state of health for both the exciter and igniter plug by monitoring the high energy pulses at the output of the exciter. By monitoring the ignition system at an intermediate point in the system such as the output of the exciter, the sensor and electronics of the device may be completely contained within the electronic environment of the exciter, thereby avoiding any need for attaching sensors at the output of the system adjacent to the igniter plug in order to diagnose the plug's state of health. As an alternative to the device being built into the ignition system, it can be incorporated into automatic test equipment that produces high energy pulses for delivery to an igniter plug to be tested.

Abstract: In a wetness sensor for a window of a motor vehicle, a heating resistor arranged in the window and powered by DC current can be connected to a measuring device for measuring an AC impedance of the heating resistor, in particular the capacitive portion thereof. The impedance varies with the amount of wetness and, thereby, serves as a measure of the wetness. A capacitor is used to bring the sensor near resonance for improved sensitivity.

Abstract: The fast sampling method for taking a position measurement with an electronic measurement system incorporating a capacitive position transducer of this invention allows such capacitive position transducers to be used in contaminant filled environments, such as on a shop floor or in the outdoors. By sampling the output signals within 25 ns-35 ns from when the input signals were applied to the capacitive position transducer, the adverse effects of resistive contamination can be avoided.

Abstract: A semiconductor device has a first-conduction-type semiconductor substrate (19), an internal circuit including a vertical bipolar transistor (18) formed in a second-conduction-type semiconductor layer (20), and a protective element (14). The protective element comprises a first-conduction-type diffusion layer (22a) formed at an upper part of a second-conduction-type semiconductor layer (20a) disposed on the semiconductor substrate (19), and a second-conduction-type diffusion layer (27, 30) formed in the first-conduction-type diffusion layer (22a). The diffusion layer (27, 30) is at least partly deeper than an emitter diffusion layer (23) of the vertical bipolar transistor (18).

Abstract: Apparatus for measuring moisture content and bulk flow rate of cotton and other bulk materials, such as wool or wood chips, while they are being transported on a belt conveyor. The apparatus comprises resistance-sensing electrode fingers pendulously mounted over the conveyor, the movement of the resistance-sensing fingers being halted in their downward arcuate path by the sensed material. The weight of the electrode assembly presses the fingers against the material with uniform pressure. The angular displacement of the fingers about an axis of suspension is used as a measure of bulk flow rate.

Abstract: A relay test apparatus for testing a protective relay operation of a protective relay system comprises GPS receivers, respectively connected to the protective relays, each GPS receiver analyzing time data included in a signal transmitted from a satellite and outputting a time signal, simulation signal generators, respectively connected to the protective relays, each simulation signal generator generating a simulation signal and inputting the simulation signal to a corresponding protective relay, and synchronous starting units, respectively provided in the protective relays, each synchronous starting unit starting a corresponding simulation signal generator to generate the simulation signal, when time signals output from the GPS receivers coincide with a preset time at a same time.

Abstract: The measurement of moisture content in granular materials is ordinarily a difficult measurement to make. The invention of this application sets forth a new method and apparatus for measuring moisture content in a wide variety of materials by means of application of an apparatus that makes measurement of moisture content independent of density of the material measured, and thereby unaffected by ambient conditions. The apparatus also allows the practitioner of this invention to readily and accurately measure moisture content.

Abstract: An elongate, flexible sensor for sensing an electrically conductive liquid, such as water, has two flexible electrodes extending along the sensor and two flexible sleeves extending therealong and being attached adhesively to each other along the sensor. Each electrode is a ribbon made from a carbon-filled, silicone rubber material. Each sleeve extends around an associated one of the electrodes and is braided from a filamentary, polyester material so as to define multiple apertures enabling such a liquid reaching the sensor to pass through the sleeves so as to cause a short circuit between the electrodes.

Abstract: A capacitance detector comprises switches for charging and discharging a sensing part, an integrator constituted by a condenser and an operational amplifier for integrating a charging current or a discharging current which is generated according to the charging and discharging the sensing part, a switch for charging an output voltage of the operational amplifier and for feedbacking an electric charge to the integrator, and a condenser. The capacitance detector can be provided by the operational amplifier having a low response performance and a small output current and no hold sample circuit, thereby a circuit scale of the capacitance type sensor can be made small.

Abstract: A highly accurate electromagnetic-induction-type conductivity and dielectric constant meter is obtained by using a calibration box (instrument) and a structure as below. The conductivity and dielectric constant meter employs an electromagnetic inductive probe which includes a primary transformer composed of a toroidal core with a wound primary coil, a secondary transformer composed of a toroidal core with a wound secondary coil, an electrostatic shield shielding the transformers, and cables that connect the probe to a meter. To eliminate the electrostatic capacity produced by causes other than electromagnetic induction, the structure of the probe is symmetrical. In a first embodiment, the secondary transformer is placed between two parts of the primary transformer, which has two cores of the same shape that are placed symmetrically.

Abstract: A method for detecting gaps to be bridged in a power supply of an electric rail vehicle includes continuously sensing at least one conductor rail for gaps with at least one contact signal transmitter travelling ahead of a plurality of electrically interconnected real current collectors, as seen in the direction of travel of the rail vehicle, with signal information obtained being stored. An instantaneous contact situation between the real current collectors and the conductor rail is determined from the memory contents. Positions of a virtual current collector travelling in advance are formed for each real current collector from the memory contents, with the distances between the contact signal transmitter and the virtual current collectors being such that a necessity to change over the traction power converter into the regenerative braking mode is indicated as soon as all of the virtual current collectors meet a gap in the conductor rail.

Abstract: A circuit continuity test device is disclosed. The device utilizes a series circuit to provide a completed circuit for an external explosive or pyrotechnic circuit. The series circuit has a switch in the form of a light emitting diode and a power source. Upon coupling to a continuous external circuit, the diode is placed in an on state thereby illuminating and indicating a continuous external circuit.The device housing is a simple, compact and solid part. This allows the device to be used in a variety of environmental conditions and easily and inexpensively manufactured.

Abstract: A capacitive fluid level sensing pipette probe adapted to be used in an automated random access immunoassay analyzer is provided. The pipette probe comprises an elongated shaft having a conductive tip. An integrated circuit chip containing capacitive sensing circuitry is positioned on the pipette probe itself, or in very close proximity. With this arrangement, the sensing circuitry moves with the pipette probe as it is raised and lowered into and out of a vessel containing a liquid. Thus, errors associated with capacitance caused by flexing connector cables is eliminated. Flex tape wiring may be used to carry data from the capacitive sensing circuitry on the pipette probe to the processing board of the automated immunoassay analyzer.