Peak Voltmeters Patents (Class 324/103P)
  • Patent number: 6091236
    Abstract: The present invention provides a system and method for monitoring an electrical signal appearing on a rotating machine shaft. The system comprises a probe assembly for placement against the rotating machine shaft that is in electrically conductive contact with the shaft. The probe assembly includes at least one circuit for receiving the electrical signal from the rotating machine shaft and producing various electrical signals that are read by a data processing system, which is coupled to the circuit. The data processing system determines from the electrical signal obtained from the circuit, the RMS AC voltage, DC voltage, peak voltage, and the RMS AC and DC current through two different resisters that are all appearing on the rotating machine shaft. The data processing system also performs Fast Fourier Transforms on the RMS voltage and current signals and produces a frequency spectrum over time.
    Type: Grant
    Filed: April 28, 1997
    Date of Patent: July 18, 2000
    Assignee: CSI Technology, Inc.
    Inventors: Richard W. Piety, Stewart V. Bowers, III, David Q. Gaddis
  • Patent number: 5777465
    Abstract: A circuit for use with a magnetic sensing device having at least first and second sensors has a summing amplifier for providing a difference signal and a peak detector for detecting peaks in the difference signal. The peaks determine a spatial offset of a transition in a sensed body.
    Type: Grant
    Filed: February 16, 1996
    Date of Patent: July 7, 1998
    Assignee: Analog Devices, Inc.
    Inventor: William Walter
  • Patent number: 5721486
    Abstract: The device proposed comprises a Hall sensor (101) with an associated magnet (102), a pulse-generation wheel (104) rotating at an angular speed w and fitted with teeth having a rising and falling face, the wheel turning in front of the sensor to generate a curve which corresponds exactly to the tooth-face positions and which can be used to determine precisely the position of the rotating shaft. The Hall sensor 9101) registers the variation with time of the magnetic flux density through the pulse-generation wheel (104) as a Hall voltage signal. This signal is converted by a differentiator circuit (103.2) into a differentiated signal. The maxima and minima of the differentiated signal are determined and a digital output signal (AS) is generated form the differentiated signal, the low-level to high-level transitions in the output signal corresponding to the maxima of the differentiated signal and the high-level to low-level transitions corresponding to the minima.
    Type: Grant
    Filed: September 29, 1995
    Date of Patent: February 24, 1998
    Assignee: AB Elektronik GmbH
    Inventor: Peter Pape
  • Patent number: 5706222
    Abstract: A peak detector having several novel detection modes including detecting a pair of peaks with opposite polarity and selecting whether or not the peaks must cross programmed thresholds to be detected. The novel detection modes together with several known detection modes are provided in one unit and can be selected by the user. A power down feature is also provided.
    Type: Grant
    Filed: April 29, 1996
    Date of Patent: January 6, 1998
    Assignee: International Business Machines Corporation
    Inventors: Anthony Richard Bonaccio, Mark Andrew Bergquist, Kirk William Lang, Anthony John Perr
  • Patent number: 5608319
    Abstract: A method and apparatus for measuring magnetic fields with a magnetically sensitive probe which is introduced into a magnetic field and which transmits a measuring signal to a measuring device for evaluation. After activating the measuring device, a zero point is measured and automatically set and a correction value is calculated and stored. The probe is introduced into the magnetic field and the polarity of the magnetic field automatically determined. A peak value of a plurality of measured values is automatically stored and the measurement range of the device is automatically adjusted to the range of the magnetic field. Thereafter, the measured values are read out, the probe is removed from the magnetic field and the device is switched off.
    Type: Grant
    Filed: March 2, 1994
    Date of Patent: March 4, 1997
    Assignee: Maurer Magnetic AG
    Inventors: Albert Maurer, Urs Meyer
  • Patent number: 5574228
    Abstract: A system for measuring the frequency of oscillation of the fluid in a fluid oscillator comprising detector means, a peak detector comprising a threshold device receiving a first signal from the detector means, means for storing the signal at the output of the threshold device and comparator means providing an output signal in accordance with the relative values of the first signal and the signal from the memory means.
    Type: Grant
    Filed: June 10, 1994
    Date of Patent: November 12, 1996
    Assignee: Schlumberger Industries, S.A.
    Inventor: Alain G. Bazin
  • Patent number: 5572116
    Abstract: A surge detecting element which is connected to surge invading lines and is composed of a gap type discharge tube and a nonlinear resistor both connected in series with each other and one or more of surge absorbing elements each having an impulse discharge starting voltage higher than an impulse discharge starting voltage of the surge detecting element. A light receiving element is provided for the gap type discharge tube in light receiving relationship therewith for detecting a discharge light thereof, a counter circuit for counting a detected signal from the light receiving element is also provided.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: November 5, 1996
    Assignee: Mitsubishi Materials Corporation
    Inventors: Koichi Kurasawa, Yoshiyuki Tanaka, Takaaki Itoh
  • Patent number: 5555452
    Abstract: A peak and valley measuring circuit (40) featuring a single digital-to-analog converter (DAC) (100), a peak counter (110), a valley counter (120), and a comparator (130). The peak and valley measuring circuit (40) uses the peak counter (110) when detecting peaks of the recovered audio signal and the valley counter (120) when detecting valleys of the recovered audio signal. The DAC (100) is used in conjunction with one of the counters (110) or (120) depending on whether peaks or valleys are being detected, and is preferably a current-mode DAC.
    Type: Grant
    Filed: May 12, 1995
    Date of Patent: September 10, 1996
    Inventors: Edgar H. Callaway, Jr., Gary L. Pace, James D. Hughes
  • Patent number: 5541502
    Abstract: A level measuring set for low-frequency signals with superimposed direct voltage includes a low-pass filter, a measuring rectifier, and a subtractor. A low-frequency measurement signal is supplied to the low-pass filter, which outputs a reference potential (U.sub.B) which corresponds to the direct voltage. The reference potential (U.sub.B) is applied to a reference point of the measuring rectifier. The measuring rectifier forms a positive and a negative direct voltage component (+U.sub.M, -U.sub.M) superimposed on the reference potential (U.sub.B) for the positive and negative half-waves of the low-frequency signal, respectively. The subtractor receives at inputs thereof the positive and negative direct voltage components (+U.sub.M, -U.sub.M) superimposed by the reference potential (U.sub.B) and emits a level measurement value of the low-frequency measurement signal.
    Type: Grant
    Filed: February 13, 1995
    Date of Patent: July 30, 1996
    Assignee: Siemens Aktiengesellschaft
    Inventor: Klaus Hoffmann
  • Patent number: 5523676
    Abstract: An inductive load energized by a variable duty cycle pulse signal contains ripple at steady state conditions, and the average current is used as feedback to a controller. The average current is obtained without filtering by synchronously sampling the local maxima and minima of the current and averaging the last two samples. The maxima and minima are detected by sampling at the falling and rising edges of the pulse signal. The method is implemented by software in a microprocessor or by hardware comprising a pulse generator, sample and hold circuits, and an averager. The resulting average value is then asynchronously sampled by a microprocessor.
    Type: Grant
    Filed: March 31, 1994
    Date of Patent: June 4, 1996
    Assignee: Delco Electronics Corp.
    Inventors: James C. Bach, John L. Kastura
  • Patent number: 5498972
    Abstract: A device for monitoring supply voltage locally on integrated circuits after mounting on electronic component boards (11) includes at least one voltage monitor (31) as well as boundary scan means (36, 36', 37) for reading out the result of the monitoring. The monitor includes an extreme value detector (41), situated at the place on the circuit surface where voltage monitoring is desired and detecting the minimum absolute voltage between a local supply voltage lead and a local ground lead. The minimum value detector comprises one or two FET transistors at most.
    Type: Grant
    Filed: January 24, 1994
    Date of Patent: March 12, 1996
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventor: Tord Haulin
  • Patent number: 5471134
    Abstract: The invention relates to measuring apparatus for measuring the real load factor on an electricity source delivering an AC current to a consumer appliance, said apparatus comprising:a current sensor supplying a signal that is continuously proportional to the current delivered by the source;a rectifier circuit receiving said signal and supplying a rectified signal;a peak detector circuit receiving the rectified signal and extracting therefrom the peak value, which peak value can be read on an indicator; andcalibration means enabling the measuring apparatus to be set so that the peak value indicator displays 100% when the measured peak value of the AC current reaches the specified maximum level.
    Type: Grant
    Filed: November 24, 1992
    Date of Patent: November 28, 1995
    Assignee: Saft
    Inventors: Jean-Claude Oudille, Antonio Veiga
  • Patent number: 5406196
    Abstract: A maximum voltage detecting apparatus for measuring the output maximum voltage, such as of an optical sensor, a thermal sensor or a wind sensor, utilizing a ferroelectric substance. A d.c. power source of a reset circuit applies a d.c. voltage to a ferroelectric device to generate a maximum spontaneous polarization, the ferroelectric device including metal electrodes and a PZT ferroelectric substance held therebetween. The output voltage such as from the wind sensor is applied to the ferroelectric device so as to have an opposite polarity. A polarization measuring circuit measures a residual polarization in the ferroelectric device by this output voltage and measures a maximum output voltage value from the residual polarization value.
    Type: Grant
    Filed: September 30, 1992
    Date of Patent: April 11, 1995
    Assignee: Rohm Co., Ltd.
    Inventor: Katsumi Sameshima
  • Patent number: 5399964
    Abstract: A peak amplitude detector for use in a synchronized position demodulator associated with a linear variable differential transformer. The peak amplitude detector adjusts for phase shift in the transformer and maintains the full bandwidth of the transformer. The detector obtains the maximum positive or negative amplitude of the sinusoidal signal at one of the secondary windings of the transformer by first counting either a positive or negative half cycle of the signal and then while down counting one half of the counted half cycle sampling the amplitude of the sinusoidal signal. The sampling ends when the count reaches zero.
    Type: Grant
    Filed: August 23, 1993
    Date of Patent: March 21, 1995
    Assignee: Elsag International N.V.
    Inventor: Allan C. Zoller
  • Patent number: 5334930
    Abstract: A peak detection circuit accurately detects peaks even if a noise component is included in the input signal. The peak detection circuit includes: a differentiating circuit which produces a differentiated signal of an input signal, a peak hold circuit which produces a peak value envelope of an output of said differentiating circuit, and a first comparator which compares an output of said differentiating circuit and a reference signal formed on the basis of an output of said peak hold circuit, and which detects when said input signal falls below said reference signal A second comparator detects a portion which exceeds an output of said differentiating circuit A flip-flop produces a signal which rises in accordance with an output of said second comparator and falls in accordance with an output of said first comparator, thereby to form a signal representing a peak by the rise of an output of said flip-flop.
    Type: Grant
    Filed: May 13, 1992
    Date of Patent: August 2, 1994
    Assignee: Nippon Conlux Co., Ltd.
    Inventors: Akira Onodera, Koichi Yamazaki
  • Patent number: 5332962
    Abstract: A peak voltage detector to measure the peak output voltage of light sensors, heat sensors and the like without the need for a reference voltage. In a ferroelectric element, the ferroelectric body is positioned between PT electrodes. The ferroelectric body has a thickness that progressively varies from one end to the other. A D.C. voltage dependent upon the direct current power supply is applied to generate a maximum spontaneous polarization Pr. The output voltage from light sensors, heat sensors and the like is of a reverse polarity with respect to that of the power supply. The output voltage is applied to the ferroelectric element. Depending on this external voltage, reverse polarization will be generated in either one part, certain parts, or all of the ferroelectric element. By measuring this reverse polarization with the polarization measuring circuit, the peak value of the external voltage is measured.
    Type: Grant
    Filed: October 2, 1992
    Date of Patent: July 26, 1994
    Assignee: Rohm Co., Ltd.
    Inventor: Katsumi Sameshima
  • Patent number: 5325050
    Abstract: A maximum voltage detecting apparatus for detecting the maximum voltage output from a light sensor, a wind force sensor or the like by using ferroelectric capacitors, and a method of producing ferroelectric capacitors. A plurality of ferroelectric capacitor devices each of which is composed of one ferroelectric capacitor or a plurality of ferroelectric capacitors which have approximately the same thickness and which are connected in series and are arranged in an array are connected in parallel so as to provide a ferroelectric unit. A DC voltage is applied to the ferroelectric unit so as to produce spontaneous polarization. An output voltage of a wind force sensor or the like is applied to the ferroelectric unit at the opposite polarity, and whether or not the polarization of each ferroelectric capacitor device is reversed is detected, thereby detecting the maximum value of the external voltage.
    Type: Grant
    Filed: October 9, 1992
    Date of Patent: June 28, 1994
    Assignee: Rohm Co., Ltd.
    Inventor: Katsumi Sameshima
  • Patent number: 5220276
    Abstract: The crest value and RMS value of a signal are measured. The ratio of the two values, the crest factor, is calculated to provide a measure of the signal wave shape. The frequency range and accuracy of a commercially available RMS converter is improved by providing an improved rectifier ahead of the converter's internal rectifier. This improved rectifier is also used to form the absolute value of the input signal. A peak detector then provides the crest value (absolute peak value). The crest value and RMS value are multiplexed to a computer having an A/D converter. The RMS value, crest value and crest factor can be calculated and displayed and/or stored by the computer.
    Type: Grant
    Filed: August 26, 1991
    Date of Patent: June 15, 1993
    Assignee: Keithley Corporation
    Inventor: Meindert Kleefstra
  • Patent number: 5214319
    Abstract: A pulse detector keeps track of the peak value of an analog input signal and clocks output data pulses into a flipflop and shift register at peak values thereof while it monotonically increases in magnitude for each polarity. The data input to the flipflop becomes logic zero once the analog input signal changes direction toward the opposite polarity, whereby the last output data pulse in the shift register corresponds to the maximum peak of the analog input signal during the given polarity.
    Type: Grant
    Filed: September 11, 1992
    Date of Patent: May 25, 1993
    Assignee: Motorola, Inc.
    Inventor: Behrooz L. Abdi
  • Patent number: 5206600
    Abstract: A system and method for determining the complex impedance of a load, such as an antenna in an RF transmission system. The system samples both the voltage and current of the signal passing through a transmission line and directly derives digitally the impedance parameters independently of the amplitude or phase of the signal.
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: April 27, 1993
    Assignee: Harris Corporation
    Inventor: Richard H. Moehlmann
  • Patent number: 5185569
    Abstract: A peak value detecting circuit has a peak voltage holding circuit, a voltage comparing section, a holding voltage control circuit, and a signal output circuit. The peak voltage holding circuit holds a peak value of an input signal voltage. The voltage comparing section compares the peak voltage held by the peak voltage holding circuit with an externally input signal voltage. The holding voltage control circuit controls the level of the peak voltage in accordance with the output given by the voltage comparing section as a result of the compare operation in the latter. The signal output circuit acts as a buffer in sending to the outside the peak voltage held by the peak voltage holding circuit. The output voltage from the signal output circuit is fed back as a reference voltage to a compare input terminal of the voltage comparing section and prevents any offset that may develop in the signal output circuit from appearing in the output signal voltage of the peak value detecting circuit.
    Type: Grant
    Filed: August 13, 1991
    Date of Patent: February 9, 1993
    Assignee: Sony Corporation
    Inventors: Masayuki Katakura, Masaaki Ishihara
  • Patent number: 5119426
    Abstract: A linear display device provides a floating bar type of display for instantaneous peak values and instantaneous average values of an audio signal. Pairs of respective peak and average comparators are coupled to a source of fixed value bias voltages. The comparators produce outputs when the peak value and the average value of the audio signal exceeds the bias voltage. A logic circuit connected to outputs of each pair of comparators provides an output only when the bias voltage exceeds the instantaneous peak value.
    Type: Grant
    Filed: June 7, 1990
    Date of Patent: June 2, 1992
    Assignee: Peavey Electronics Corporation
    Inventor: John H. Roberts
  • Patent number: 5083282
    Abstract: A transition state detecting device of the invention is a device which is applied to the output stage of a detecting circuit such as a spectrum analyzer so as to display the waveform of an input signal in the form of a parameter and evaluate its characteristics. In order to perform real-time, quantitative measurement, the device includes a differentiating means (1) for differentiating an input signal and outputting a differential signal representing a transition state of the input signal, and a detecting means (2) for detecting the peak value of the differential signal output from the differentiating means and outputting a parameter corresponding to the transition state of the input signal.
    Type: Grant
    Filed: November 27, 1989
    Date of Patent: January 21, 1992
    Assignee: Anritsu Corporation
    Inventors: Aiichi Katayama, Kenji Nakatsugawa, Hitoshi Sekiya, Takafumi Nakamura
  • Patent number: 5055773
    Abstract: DC offset is measured by separating the positive and negative half cycles of the AC waveform, obtaining a measure of the energy content of each type of half cycle and subtracting one from the other and accumulating the result. The accumulated result is measured against a threshold which is selected to have a known relationship to the units used to measure the DC offset. Each time the threshold is exceeded, this increments a counter and at the same time resets the accumulator. The contents of the counter can then be multiplied by an appropriate scaling factor. The square root of this result gives a measure of DC offset.
    Type: Grant
    Filed: April 17, 1990
    Date of Patent: October 8, 1991
    Assignee: Alcatel N.V.
    Inventors: Lloyd S. Thomas, Evan J. Stanbury
  • Patent number: 5034680
    Abstract: A digital level display device wherein the digital input signal is converted into an absolute value and further converted into its logarithm. The peak of the logarithm is detected and latched. A CPU reads the latched peak and converts into it into a signal for display.
    Type: Grant
    Filed: August 19, 1987
    Date of Patent: July 23, 1991
    Assignee: Pioneer Electronic Corporation
    Inventors: Shizuo Kakiuchi, Hiroshi Iizuka
  • Patent number: 5027285
    Abstract: An AC waveform monitoring system includes detecting circuitry for providing a sensed analog signal. Oscillator circuitry is coupled to the detecting circuitry for providing a zero crossing signal. The oscillator circuitry is synchronized with a frequency of the sensed analog signal. Signal processing circuitry is coupled to both the detecting circuitry and the oscillator circuitry for identifying a peak voltage signal and an integral volt-seconds signal of the sensed analog signal responsive to the zero crossing signal. Digital processing circuitry is coupled to the signal processing circuitry and the oscillator circuitry. The digital processing circuitry includes memory for storing a plurality of predetermined signal voltage boundary values and a program utilizing the identified peak voltage signal, the integral volt-seconds signal and the stored predetermined signal values to identify an abnormal voltage event.
    Type: Grant
    Filed: February 28, 1989
    Date of Patent: June 25, 1991
    Assignee: Oneac Corporation
    Inventors: Andrew McCartney, Charles DeWitt, William Elliott
  • Patent number: 4970458
    Abstract: A voltage-sensing circuit producing a voltage-indicating signal representative of the voltages in a three-phase AC system produces several voltage-indicating signals which are representative of the phase voltages in a three-phase AC system. These voltage-indicating signals are squared, and the squared voltages are summed to produce an output signal having a DC voltage component with a magnitude proportional to the Mean Square value of the AC phase voltages. Unbalanced voltages in the three-phase system can be monitored by detecting the peak value of a ripple voltage imposed on the DC voltage component of the output of the circuit.
    Type: Grant
    Filed: May 8, 1989
    Date of Patent: November 13, 1990
    Assignee: Westinghouse Electric Corp.
    Inventor: David A. Fox
  • Patent number: 4965512
    Abstract: The current peak detector can be described as four separate sections. The first section is power distribution. The second is the analog section where the Idd current transient peak is first detected. There are two analog sections, one for Idd internal, and another for Idd external. The third section is the automatic multiplexer that controls which of the two analog sections will drive the digital section. The fourth and final section is the digital section where a voltage that is analogous to the peak current is converted to a DC voltage level with infinite memory. The digital section performs the logic function of replacing any prior digitized voltage peak with any higher voltage peak that may occur during the test period.
    Type: Grant
    Filed: October 18, 1989
    Date of Patent: October 23, 1990
    Assignee: International Business Machines Corporation
    Inventors: David E. DeBar, Indravadan J. Shah
  • Patent number: 4956600
    Abstract: A line isolated current detector for detecting low frequency peak to peak currents on a high frequency chopped line with a first series diode and resistor detecting positive waves and a second series diode and resistor detecting negative waves. First and second capacitors across the first and second resistors, respectively, temporarily store positive and negative detected waves. A third series diode and resistor connected in parallel across the first series diode and resistor and a fourth series diode and resistor connected in parallel across the second series diode and resistor allows faster charging and slower discharging of the capacitors. This allow the capacitors to charge waveforms quick enough to use a high frequency current transformer sensing a high frequency chopped line and discharge waveform slow enough to reconstruct the low frequency waveform before high frequency chopping to allow accurate current measurements of direct current or low frequency currents using a current transformer.
    Type: Grant
    Filed: July 1, 1988
    Date of Patent: September 11, 1990
    Assignee: Viteq Corporation
    Inventor: Alex J. Severinsky
  • Patent number: 4931724
    Abstract: A digital level indicating device for use in compact disk players digital audio tape recorders, etc., which includes a converter circuit for converting a digital signal applied thereto to an absolute value signal representative of an absolute value of the digital signal. A peak holding circuit detects and holds a peak of the absolute value signal. A first decoder log-converts the absolute value signal. A second decoder log-converts a signal held by the peak holding circuit. Indicator means display a level of the digital signal in accordance with outputs from both the first and second decoder. A selector switches the choices of resolution of the first decoder and the second decoder.
    Type: Grant
    Filed: July 21, 1989
    Date of Patent: June 5, 1990
    Assignee: Pioneer Electronic Corporation
    Inventors: Shizuo Kakiuchi, Hiroshi Iizuka
  • Patent number: 4922188
    Abstract: An electrical peak value measuring and evaluating apparatus including a transmitting circuit for transmitting peak values to an output, restoring circuit for restoring the level in the transmitting circuit to a known value after reaching a peak, and a retaining circuit for retaining the restored signal at the known value until the input signal again rises above a predetermined level.
    Type: Grant
    Filed: August 20, 1984
    Date of Patent: May 1, 1990
    Assignee: Kistler Instrumente AG
    Inventor: Giorgetta Mario
  • Patent number: 4920311
    Abstract: User selection of meter ballistics is accomplished by separating the meter display from the meter drive circuitry. An input signal is input in parallel into appropriate level determining circuits, with the outputs being selected for processing by a microprocessor. The microprocessor processes the selected outputs according to a ballistic standard selected by an operator to generate a display signal. For LED displays the display signal has a bar component that illuminates all the LEDs up to the maximum level of the displayed output and a dot signal that illuminates only one or a very few LEDs around the maximum level of the displayed output.
    Type: Grant
    Filed: October 27, 1988
    Date of Patent: April 24, 1990
    Inventors: Robert Bateman, Donald R. Christensen
  • Patent number: 4910455
    Abstract: A current measuring circuit for an integrated circuit comprises an operational amplifier (22), the non-inverting input terminal of which is grounded through a first resistor (23) having a value R.sub.B and a second resistor (21) having a value R.sub.2, the junction of those two resistors receiving the current (I.sub.NL) to be measured, and the output of which is connected by an inverter (26) to a MOS transistor (27). The biasing voltage of the operational amplifier and the characteristics of the inverter are chosen so that the MOS transistor is biased at its threshold in the absence of a current to be measured, whereby the output voltage V.sub.s is correlated with the current to be measured by a linear relation independent of the temperature.
    Type: Grant
    Filed: March 6, 1989
    Date of Patent: March 20, 1990
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventor: Bruno Nadd
  • Patent number: 4906864
    Abstract: A linear slope peak detector is disclosed in which the output of an integrator is compared to an input signal and a low impedance path is provided for quickly capturing peaks while at the same time minimizing droop between peak refreshes. The peak detector is well suited for determining DC offsets.
    Type: Grant
    Filed: June 19, 1989
    Date of Patent: March 6, 1990
    Assignee: United Technologies Corporation
    Inventor: Gary A. McCorkle
  • Patent number: 4902964
    Abstract: An electronic demand register includes a microprocessor including a program clock for performing timekeeping functions for the register. A power supply connected across the AC voltage source provides power to the microprocessor through a voltage regulator. The program clock is maintained by the line frequency of the AC source. Electronic circuits are provided for calibrating the program clock to be compatible with either a 50 Hz or a 60 Hz line frequency. A detection signal corresponding to the line frequency is generated by a line frequency detector circuit in the power supply. A reference signal is generated by a quartz crystal clock. A frequency comparator circuit includes a microprocessor program that measures the time period between detection signal pulses. This time period is compared to the known period of a 50 Hz or a 60 Hz signal and respective counters are incremented accordingly.
    Type: Grant
    Filed: September 21, 1987
    Date of Patent: February 20, 1990
    Assignee: Landis & GYR Metering, Inc.
    Inventors: William A. Szabela, Gordon R. Burns
  • Patent number: 4896104
    Abstract: A digital peak and valley detector including a peak value address register, a valley value address register, a peak value data register, a valley value data register, a peak comparator for comparing the value stored in the peak value data register with value data contained in the digital signal applied to the digital peak and valley detector and for causing the greater of the two to be stored in the peak value data register while simultaneously storing the address in the peak value address register and a valley comparator for comparing the valley value contained in the valley value data register with the value data contained in the digital signal applied to the digital peak and valley detector for determining which is less and for causing the value and the address of the smaller of the two to be stored respectively in the valley value data and the valley value address registers.
    Type: Grant
    Filed: February 15, 1989
    Date of Patent: January 23, 1990
    Assignee: Hitachi Micro Systems, Inc.
    Inventors: Chandravadan N. Patel, Richard Wm. Blasco, Atsushi Kiuchi, Hiromitsu Inada
  • Patent number: 4870349
    Abstract: A digital level indicating device for use in compact disk players digital audio tape recorders, etc., which includes a converter circuit for converting a digital signal applied thereto to an absolute value signal representative of an absolute value of the digital signal. A peak holding circuit detects and holds a peak of the absolute value signal. A first decoder log-converts the absolute value signal. A second decoder log-converts a signal held by the peak holding circuit. Indicator means display a level of the digital signal in accordance without puts from both the first and second decoder. A selector switches the choices of resolution of the first decoder and the second decoder.
    Type: Grant
    Filed: August 19, 1987
    Date of Patent: September 26, 1989
    Assignee: Pioneer Electronic Corporation
    Inventors: Shizuo Kakiuchi, Hiroshi Iizuka
  • Patent number: 4862287
    Abstract: A dot line printer is releasably connected by a control circuit to the output of a monitor which senses variations or faults in the AC line voltage for a computer or the like. Each time the monitor senses any one of the five different voltage disturbances, the information is transmitted as digital data to the printer, which then produces a continuous strip chart or graphical printout of the voltage variations. The printer advances paper continuously and in small increments, while printing thereon six parallel trace lines that extend in the longitudinal or feed direction of the paper. One trace line represents time, and the remaining lines the zero ordinates for five different voltage faults. Whenever a fault is detected, the associated trace line widens to print a horizontal bar. When a power failure occurs and is thereafter restored, a header (indica line) is printed on the paper before printing of the trace lines resumes. The monitor and printer, if desired, may be operated independently of each other.
    Type: Grant
    Filed: September 30, 1987
    Date of Patent: August 29, 1989
    Assignee: Mendon Electronics Corporation
    Inventor: Gerald R. Paul
  • Patent number: 4851763
    Abstract: Current-measuring device including a non-contacting current sensor and an evaluating device connected downstream to the sensor for producing an output signal proportional to a current being measured, comprising a circuit arrangement for determining a zero drift of at least one of the evaluating device and the current sensor from symmetrical components of the current being measured and for correcting the drift.
    Type: Grant
    Filed: March 21, 1988
    Date of Patent: July 25, 1989
    Assignee: Heidelberger Druckmaschinen AG
    Inventors: Bertold Grutzmacher, Helmut Meyer
  • Patent number: 4843307
    Abstract: A peak to peak or two-point voltage difference measuring equipment according to the present invention comprises: a control circuit; a D/A converter for converting the digital data given from the control circuit into the reference analog voltage; a comparator for comparing an input voltage signal with a reference analog voltage; means for gating the output of the comparator for a predetermined time segment interval; and means for holding the output of the gating means and applying to the control circuit.
    Type: Grant
    Filed: April 21, 1987
    Date of Patent: June 27, 1989
    Assignee: Kabushiki Kaisha Kenwood
    Inventor: Hiroshi Ichijyo
  • Patent number: 4839584
    Abstract: A signal recording/reproducing apparatus having both bar-type and numeric signal-level displaying units which can be easily read. The apparatus includes a sample-and-hold circuit for sampling and holding an input signal at a first predetermined rate, a first display unit for displaying in bar form the sample values sampled by the sample-and-hold circuit, a data holding circuit for sampling and holding the sample values periodically at a second predetermined rate, and a second display unit for numerically displaying the sample values selected by the data holding circuit. The bar code display can change at a rapid rate to dynamically follow the input signal, while the numeric display changes at a slower rate so as to allow the user sufficient time to comprehend the numerically displayed value.
    Type: Grant
    Filed: December 28, 1987
    Date of Patent: June 13, 1989
    Assignee: Pioneer Electronics Corporation
    Inventors: Nobutoshi Fukuda, Masashi Tanabe, Yoshiki Furuta, Tatsuro Nagao, Naoto Arifuku, Shinichi Yamamisaka
  • Patent number: 4804921
    Abstract: A microprocessor controlled digital engine analyzer receives analog input signals from an engine being analyzed, engine parameter data entered via a keyboard, and function data, selecting one of several operating modes for the analyzer and which information is to be displayed, entered via the keyboard, and displays on a CRT screen the selected information such as cylinder firing order, RPM, Dwell, KV and DC volts, alphanumerically, information such as primary and secondary ignition and voltage, alternator and fuel injector information through the use of continuous waveform patterns, and additional information pertaining to Dwell, KV and Cylinder Shorting through the use of bar graphs.
    Type: Grant
    Filed: October 9, 1987
    Date of Patent: February 14, 1989
    Assignee: Snap-on Tools Corporation
    Inventors: Michael C. Putrow, Leonard J. Wisneski, Jr., Craig F. Govekar, Gary D. Jonker, Gordon Lindhard, Dennis W. Weidenbenner, Robert O. Quinn
  • Patent number: 4779045
    Abstract: A method of measuring automatically the peak-to-peak amplitude of electrical input signal utilizes both trigger circuits of a dual trigger oscilloscope. The steps of the method include adjusting automatically the trigger level of the first trigger circuit until the first trigger level is equal to the maximum peak of the input signal while adjusting automatically the trigger level of the second trigger circuit until that level is equal to the minimum peak of the signal. The second level is then subtracted from the first level to calculate the amplitude. To minimize the time involved, the method distinguishes between signals faster than and slower than a preselected frequency and calculates more rapidly the amplitude for faster signals. Time is also minimized by adjusting hysteresis levels and voltage level settling times as the trigger levels are increased and decreased in search of the peak signal values.
    Type: Grant
    Filed: January 29, 1987
    Date of Patent: October 18, 1988
    Assignee: Tektronix, Inc.
    Inventor: Gordon W. Shank
  • Patent number: 4761640
    Abstract: A method for positioning cursors at a specific point on a displayed waveform uses a cursor to determine the maximum and minimum points on the waveform about a transition portion. For each position of the cursor between the maximum and minimum points an intersection between the cursor and the waveform is computed as a percentage of the difference between the maximum and minimum points. The cursor is then positioned at a point on the transition portion where the percentage is a desired value for the specific point.
    Type: Grant
    Filed: March 24, 1987
    Date of Patent: August 2, 1988
    Assignee: Tektronix, Inc.
    Inventor: Keith R. Slavin
  • Patent number: 4751504
    Abstract: A cursor interface for a waveform display provides for movement of a waveform relative to a first cursor. When the first cursor overlies a desired point on the waveform, the cursor is locked to the waveform by transforming the cursor coordinates from display coordinates to waveform coordinates. The waveform may then be moved together with the first cursor relative to a second cursor. When the second cursor overlies another desired point on the waveform, a measurement value is displayed indicating the difference in positions on the waveform of the cursors. The cursors may be centered independently, and when locked to the waveform the result is to correspondingly move the waveform.
    Type: Grant
    Filed: March 24, 1987
    Date of Patent: June 14, 1988
    Assignee: Tektronix, Inc.
    Inventor: Keith R. Slavin
  • Patent number: 4746816
    Abstract: Circuitry for detecting a pulse having a duration as short as 10 nanoseconds. The circuitry includes a storage device for storing the peak amplitude of the pulse. Signal resolution enhancement circuitry is responsive to the storage device for establishing a plurality of channels respectively corresponding to a plurality of signal amplitude ranges where the range of signal amplitudes for each successive range is larger than that of the range preceding it. Peak signal detecting circuitry is responsive to the signal resolution enhancement circuitry for (a) scanning the channels, (b) selecting one of the channels, the selected channel being such that the peak amplitude falls within the range for the channel, and (c) detecting the peak amplitude of the pulse.Probe 10 in FIG. 1, may be replaced by an electrostatic sensor, the high input impedance of amplifiers 16 and 18 of FIG. 1 is within range of standard electrostatic charge measurements, thus the invention becomes an electrostatic sensing device.
    Type: Grant
    Filed: December 2, 1986
    Date of Patent: May 24, 1988
    Assignee: Pace Incorporated
    Inventor: Ole V. Olesen
  • Patent number: 4727314
    Abstract: A transient detector apparatus utilizing peak and slope detectors to determine the presence of transient signal in a logic signal. Individual slope measurements of the input signal are compared with a logic criteria to establish the occurrence of a transient. The peak voltage and pulse width of a transient are digitized in order to time tag or isolate a transient to a particular signal.
    Type: Grant
    Filed: August 8, 1985
    Date of Patent: February 23, 1988
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Malcom L. Lapeyrolerie, Hugh J. Murphy
  • Patent number: 4706289
    Abstract: A method and apparatus for continuously measuring and indicating the variations of the intensity of an electric signal, such as a signal to be recorded on a tape recorder, which provides measuring to take place at successive measuring periods in such a manner that a measured result is yielded representing the maximum value of the signal intensity. The signal intensity is measured during consecutive measuring periods and registered. The indicator has the ability to maintain the read-out of a maximum value, read during a measuring period, during a following hold period, whereby the measuring periods provided have a duration being an order of size less than the time of reaction of the human eye. The system stores the maximum intensity values being detected during each of a series of consecutive measuring periods, and provides hold periods having substantially longer durations by being an order of size longer than the time of reaction of the human eye.
    Type: Grant
    Filed: August 28, 1985
    Date of Patent: November 10, 1987
    Assignee: Band & Olufsen A/S
    Inventor: Jorgen S. Jensen
  • Patent number: 4692692
    Abstract: An electronic apparatus is proposed for detecting variations of significance in an electrical voltage as a function of time. The apparatus includes a tracker (2) of these variations, a comparator (6) comparing the voltage with a reference voltage V.sub.2, and a counting circuit (10, 15, 20). The tracker (2) monitors variations in the voltage supplied to a filtering and rectification system (4), which eliminates the continuous component of the signal and within the high frequency range greatly diminishes the levels of the parasitic signals having an oscillatory character. The comparator (6) furnishes a calibrated pulse (25) each time the voltage exceeds the threshold V.sub.2, and the counting circuit (10, 15, 20) counts the number of these calibrated pulses within a given time period T and furnishes a logic signal (30) if this number exceeds a predetermined quantity.
    Type: Grant
    Filed: October 4, 1985
    Date of Patent: September 8, 1987
    Assignee: Commissariat a l'Energie Atomique
    Inventor: Jean-Paul Prulhiere
  • Patent number: 4686390
    Abstract: A digital peak-hold detector for determining the peak value of an input analog voltage to be displayed on a multiple-element display device detects when the value of the input analog voltage exceeds the value of a ramp-like waveform generated from a counter which repetitively counts down from a number equal to the total number of display elements to zero to generate a compare signal. A control circuit strobes the count corresponding to the peak value into a storage register when the value of the input analog voltage exceeds the current peak value in the storage register. A digital comparator compares the current peak value from the storage register with the repetitive count from the counter and outputs an update signal when the value of the count is greater than the current peak value. The update signal is combined with the compare signal by the control circuit to make the determination whether to update the current peak value.
    Type: Grant
    Filed: June 26, 1986
    Date of Patent: August 11, 1987
    Assignee: Tektronix, Inc.
    Inventors: Edward J. Cleary, Jr., Mike R. Coleman