Patents Examined by Diep Do
  • Patent number: 5867031
    Abstract: A simplified method and apparatus for electronic pressure control with compensation for current operating temperature and pressures in which computer memory is employed for storing a plurality of firmware models which characterize the effects of temperature and pressure variations on (1) fluid flow through the flow restrictor, (2) the temperature sensor, and (3) the pressure sensor, so that control signals can be generated which compensate a plurality of thermally coupled sensors for changes in current operating temperatures and pressures.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: February 2, 1999
    Assignee: Hewlett-Packard Co.
    Inventor: Tak Kui Wang
  • Patent number: 5844412
    Abstract: A printed circuit board tester incorporating hardware for fast capacitive measurements. The circuit board tester includes a digital signal processor that can both source and measure test signals. It also includes an amplifier having an input and an output connected to probes that can contact points on the printed circuit board. In use, the board tester is configured to place a capacitor on the printed circuit board under test in the feedback path of the amplifier. The digital signal processor generates a stimulus signal to the capcitor and the output of the amplifier is passed to the digital signal processor. The digital signal processor uses an adaptive filtering approach to determine convergence of the measurement, thereby minimizing measurement time. The arrangement is flexible and can be reconfigured to measure both large and small values of capacitance.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: December 1, 1998
    Assignee: Teradyne, Inc.
    Inventor: Peter R. Norton
  • Patent number: 5831423
    Abstract: A phase meter and method of providing a voltage indicative of a phase difference between a reference signal and an input signal in which the amplitudes of the two signals are made approximately the same to cancel potential phase errors caused by different amplitudes, and the two signals are provided to two matched comparators, one receiving the input signal and the other receiving the reference signal. The two matched comparators are connected together so as to provide an output logic signal in accordance with a prescribed, unconventional, truth table. The output logic signal is a pulse whose duration is proportional to the phase difference. The output logic signal is converted to a voltage indicative of the phase difference between the reference signal and the input signal. The phase meter is relatively simple to make and a preferred embodiment measures phase shift directly with a 10 mV/degree output at up to 10 MHz.
    Type: Grant
    Filed: February 29, 1996
    Date of Patent: November 3, 1998
    Assignee: Harris Corporation
    Inventor: Ronald Alfred Mancini
  • Patent number: 5821755
    Abstract: An apparatus and method for testing a battery charger includes a converter having input terminals connectable to a battery charger for receiving a current, output terminals and a switching device for electrically connecting at least one of the input terminals to the output terminals. A load is connected to the output terminals. A controller controls the switching device to periodically connect the input terminals to the output terminals, and in a preferred embodiment, maintain a desired voltage across the input terminals.
    Type: Grant
    Filed: November 17, 1995
    Date of Patent: October 13, 1998
    Assignee: Schott Power Systems Incorporated
    Inventor: Christopher P. Henze
  • Patent number: 5818242
    Abstract: A machine having protruding elements 26 and an adjacent abradable seal 18, which move relative to each other, an air-path clearance G between the seal 18 and the elements 26 and an element distance D2 between the sensor 10 and the elements 26, is provided with a sensor 10 which is recessed within the seal 18 by a recess distance D. A clearance/thickness circuit 14 provides transmitted and reflected microwave signals 30,32 along a coaxial cable 12 having a characteristic impedance, to the sensor 10, which has an impedance substantially matched to the characteristic impedance of the cable 12. The sensor 10 provides the reflected signal 32 which is indicative of the recess distance D when the elements 26 are not in front of the sensor 10 and is indicative of the blade distance D2 between the sensor 10 and the elements 26 when the elements 26 are in front of the sensor 10.
    Type: Grant
    Filed: May 8, 1996
    Date of Patent: October 6, 1998
    Assignee: United Technologies Corporation
    Inventors: Richard R. Grzybowski, Gerald Meltz
  • Patent number: 5801534
    Abstract: An alternating current ignition system which can be used in one of two ways for ion current measurement. On the one hand, an oscillating circuit at the primary end of the ignition coil can be driven such that, after ignition has taken place, an alternating current signal is generated at the primary end; the amplitude of the alternating current signal must be sufficiently low so as not to cause any sparks at the secondary end, but lead to an alternating voltage signal which is modulated in relation to the ionisation degree of the ignition spark gap and thus represents an ion current measurement signal. On the other hand, however, if an auto transformer is used as an ignition coil, the intermediate circuit voltage applying at the primary end will be modulated in the medium-high voltage range of, e.g, 180 V in relation to the degree of ionisation, so that this supply voltage is used as a measurement signal.
    Type: Grant
    Filed: July 3, 1996
    Date of Patent: September 1, 1998
    Assignee: Temic Telefunken microelectronic GmbH
    Inventors: Peter Hohner, Jens Schirmer
  • Patent number: 5793212
    Abstract: A method for testing the reliability of a dielectric film on semiconductor substrate comprises of the steps of: establishing a current value corresponding to a first order, an order being defined as the selected current applied within a preselected set time-increment, in which the current is first applied for testing the reliability of the dielectric film deposited on the semiconductor substrate; applying the established current of the first order to the dielectric film; applying the next current corresponding to each of the subsequent orders until the dielectric film is broken down, wherein the current value corresponding to each of the subsequent orders is increased in steps over the subsequent orders; and measuring the charge value until the dielectric film is broken down, wherein the current value corresponding to each of the orders is divided by a predetermined denominator value and each of the divided values are applied cumulatively in sub-steps with the order to the dielectric film a number of times eq
    Type: Grant
    Filed: March 11, 1997
    Date of Patent: August 11, 1998
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventor: Kum-Yong Om
  • Patent number: 5793217
    Abstract: A capacitance sensor assembly for use with a label detection and registration system for detecting a lateral edge of a label on a web bearing a plurality of such labels and moving in a longitudinal direction through a capacitance gap in the sensor assembly. The capacitance sensor assembly includes a reference plate electrode, and a pair of sensor electrodes extending substantially parallel to and spaced apart from the reference plate electrode to form the capacitance gap. The pair of sensor electrodes has a differential capacitance, when the web bearing the plurality of labels thereon is in the capacitance gap, which is used to provide a signal indicative of the lateral edge of the label.
    Type: Grant
    Filed: March 28, 1997
    Date of Patent: August 11, 1998
    Assignee: Automated Quality Technologies, Inc.
    Inventor: Raymond W. Herbst, Jr.
  • Patent number: 5789926
    Abstract: A method and apparatus for detecting and indicating the number of times a CRT unit arcs. The apparatus is constructed of a ferrite split toroid core wound with wire which is coupled around the focus lead and/or ground lead of a CRT through which a current spike will occur during an arcing event. The wound wire is coupled to a current pulse detector which in turn is coupled to a monostable mode timer and counter for counting the number of arcing events. The counter is coupled to a display device for displaying the number of times the CRT has arced.
    Type: Grant
    Filed: October 16, 1996
    Date of Patent: August 4, 1998
    Assignees: Sony Corporation, Sony Electronics Inc.
    Inventor: Mahmoud Badenlou
  • Patent number: 5789928
    Abstract: A circuit to discriminate the source of harmonic distortion of the output voltage comprises voltage sensors coupled to the output terminals of a source of electric power and to a point of regulation remote from the source for sensing the output voltage waveform present at each of these locations. The circuit then utilizes these two sensed waveforms to discriminate the source of any harmonic distortion between the source of electric power and the utlization equipment. This circuit calculates the percentage total harmonic content of each of the sensed waveforms, and compares them to determine the source of distortion. If the percentage total harmonic content sensed at the point of regulation is greater than that sensed at the terminals of the source of electric power, the source of distortion is discriminated to be the utilization equipment; otherwise, the source of distortion is identified to be the source of electric power.
    Type: Grant
    Filed: November 1, 1995
    Date of Patent: August 4, 1998
    Assignee: Sundstrand Corporation
    Inventor: Roy S. Baker
  • Patent number: 5790037
    Abstract: A polarity indicator (10) for identifying the polarity of the terminals (104 and 106) of a vehicle battery (102). The indicator includes a housing (12) which is mounted by a fastener (14) on to the vehicle battery. The top wall (12A) of the housing has positive and negative indicia (16 and 18) for assisting the user in identifying the terminals of the vehicle battery. An electrical circuit is mounted within the housing of the indicator. The circuit includes a pair of light bulbs (30), a battery (32) and a time delay opening switch (34). The indicator is activated by pressing the button (34A) of the switch to complete the circuit which causes the light bulbs to illuminate the positive and negative indicia of the indicator.
    Type: Grant
    Filed: December 16, 1996
    Date of Patent: August 4, 1998
    Inventor: Allen D. Walblay
  • Patent number: 5760589
    Abstract: The present invention provides a sheet thickness measuring apparatus comprising electrostatic capacity measure means for measuring the electrostatic capacity of a sheet, resistance measure means for measuring a resistance value of the sheet, and calculation means for calculating a thickness of the sheet on the basis of the electrostatic capacity measured by the electrostatic capacity measure means and the resistance value measured by the resistance measure means.
    Type: Grant
    Filed: May 2, 1997
    Date of Patent: June 2, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventor: Ichiro Katsuie
  • Patent number: 5757196
    Abstract: A capacitive proximity or limit switch comprises a capacitive probe having a sensor electrode and a guard electrode. The sensor electrode is connected to an oscillator formed by a feedback system of two operational amplifiers, of which one operational amplifier is configured as a differential amplifier, the other operational amplifier as a voltage follower. The probe electrode is connected to the inverting input of the differential amplifier, in the feedback circuit of which a capacitor is provided, as a result of which the AC gain is determined. An adjustable portion of the output voltage of the differential amplifier is applied to the non-inverting input of the voltage follower, the output of which is connected to the non-inverting input of the differential amplifier to which the guard electrode is connected.
    Type: Grant
    Filed: September 26, 1996
    Date of Patent: May 26, 1998
    Assignee: Endress + Hauser GmbH + Co.
    Inventor: Gustav Wetzel
  • Patent number: 5751147
    Abstract: A preignition detecting method which prevents preignition (PI) from being misjudged as having occurred when an ignition plug is fouling. It is determined whether or not the ignition plug fouls in accordance with a voltage, developed across a detecting resistor which is fetched into a microcomputer 18 at a relatively early timing after an ignition command signal is outputted from an ignition device. Further it is determined whether or not preignition occurs in accordance with another voltage fetched at a relatively late timing after the ignition command signal is outputted. When it is determined that the ignition plug is fouling, it is inhibited to fetch the another voltage at a relatively late timing to prevent a misjudgment that preignition occurs due to a leakage current from being caused though preignition does not actually occur.
    Type: Grant
    Filed: May 28, 1997
    Date of Patent: May 12, 1998
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Koichi Nakata, Kazuhisa Mogi, Youichi Kurebayashi
  • Patent number: 5744972
    Abstract: The device has a single strip having a first end, a second end, a length and a width. The first end of the strip is curved toward the second end of the strip to form a loop having a height. The length is approximately 10 mm, the width is approximately 5-8 mm, and the height is approximately 0.8-1.2 mm. The loop is preferably fabricated from copper. The loop is mounted directly to a test instrument such as a computer controlled impedance analyzer or network analyzer. The test instrument measures the inductance and resistance of the loop with no thin film sample placed therein, and then measures the inductance and resistance of the loop containing the sample under test. From these measurements, the device ultimately derives the permeability of the sample under test.
    Type: Grant
    Filed: April 5, 1996
    Date of Patent: April 28, 1998
    Assignee: Lucent Technologies Inc.
    Inventors: Vladislav Korenivski, Zhengxiang Ma, Paul Matthew Mankiewich, Paul Anthony Polakos, Robert Bruce van Dover
  • Patent number: 5744961
    Abstract: A lamp disconnection detecting device includes a magnetic core with a gap; a plurality of detecting coils the number of turns of which are different from one another and are proportional to 2.sup.n (where n=0, or positive integers), and a magnetic response section provided in the gap of the magnetic core.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: April 28, 1998
    Assignee: Yazaki Corporation
    Inventor: Michihiro Otaka
  • Patent number: 5744963
    Abstract: While a power source is being supplied from a sub-battery by a voltage-current change trend calculating section, the voltage-current change trend calculating section collects currents from a battery and terminal voltages. A voltage-current approximate straight line calculating section obtains an approximately linear function, and a battery residual capacity calculating section obtains a residual capacity voltage based upon the approximately linear function and open-circuit voltages. A current storage stop discriminating section integrates the currents while the residual capacity voltage is lower than a previous residual capacity voltage, and when supplying from the sub-battery is stopped, obtains total capacity according to the open-circuit voltages at the stop and supplying and according to the integrated currents.
    Type: Grant
    Filed: February 29, 1996
    Date of Patent: April 28, 1998
    Assignee: Yazaki Corporation
    Inventors: Youichi Arai, Kenichi Shimoyama, Tsutomu Saigo, Yoshihide Takada
  • Patent number: 5744965
    Abstract: A system for monitoring the integrity of electrical connections includes a transformer with its primary coupled across a dual split contact arrangement and the secondary coupled to both an energy source and a monitoring circuit. When the contact condition is made the secondary impedance reaches a given value which results in a low output indicated by the monitoring circuit. The energy source is preferably a radio frequency oscillator driving the transformer secondary, which is also connected to a monitoring circuit. Preferably, the output from a current reference circuit, coupled to the secondary of the transformer, is coupled to the energy source circuit and the monitoring circuit so as to produce a given output in the monitoring circuit when the contact condition is made.
    Type: Grant
    Filed: September 17, 1996
    Date of Patent: April 28, 1998
    Assignee: Lucent Technologies Inc.
    Inventors: Gabriel Lorimer Miller, Eric Richard Wagner
  • Patent number: 5744964
    Abstract: For a print-circuit board 10 of a good product, probes 31 and 32 are made to be electrically continuous with a ground plate 13 and a wiring pattern i respectively to measure a capacitance Cgi, which is then stored in a storage device 44. A capacitance Ci of a print-circuit board 10, the object of testing, is measured in a similar manner and a ratio .mu.=(average value Ca of a several measured capacitance value of the object of testing/(average value Cga of the corresponding measured capacitance values of the good product) is calculated. If Ci<Cgj(1-.DELTA.e0) or Ci>Cgj(1+.DELTA.e0), the measured capacitance values Ci and Cgjare excluded from the objects of calculation of the average values. If Cj<.mu..Cgj(1-.DELTA.e) or Cj>.mu..Cgj(1+.DELTA.e), a wiring j is judged to be defective and the resistance measuring method is employed to judge the details of the defect. The tolerance rate .DELTA.e0 and .DELTA.e are 0.15 and 0.02 respectively.
    Type: Grant
    Filed: July 25, 1996
    Date of Patent: April 28, 1998
    Assignee: Fujitsu Automation Limited
    Inventors: Morishiro Sudo, Masaru Ishijima, Kazuo Yamazaki
  • Patent number: 5739692
    Abstract: A device for monitoring voltage and amperage on an article being electrocoated with a primer composition in an aqueous electrocoating bath which contains the following components: a sealed container for holding electrical components; a recording device positioned in the container for recording voltage and amperage; a voltage measuring circuit board positioned in the container and electrically connected to the recording device containing an electrical circuit for measuring; a first electrical probe positioned on the article being electrocoated and electrically connected to the circuit of the circuit board for measuring voltage and a second electrical probe for measuring amperage positioned on the article being electrocoated and electrically connected to the recording device; whereby as the article being electrocoated with a primer composition is passed through an aqueous electrocoating bath, measurements of voltage and amperage are being taken at set time intervals as the article is passing through electrocoat
    Type: Grant
    Filed: November 8, 1995
    Date of Patent: April 14, 1998
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Joseph John Subda, Jr.