Patents Examined by W. Edmonds
  • Patent number: 5227721
    Abstract: A superconductinve magneto-resistive device for use in a sensor system for sensing an external magnetic field which is formed so as to have a predetermined pattern for a current path through which a supplied current flows. The pattern includes portions formed close and parallel to each other so that magnetic fields induced by respective currents flowing through the portions can be cancelled with each other.
    Type: Grant
    Filed: October 5, 1990
    Date of Patent: July 13, 1993
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Shoei Kataoka, Hideo Nojima, Shuhei Tsuchimoto, Ryusuke Kita, Susumu Saitoh
  • Patent number: 5126667
    Abstract: A superconductive magneto-resistive device for use in a sensor system for sensing an external magnetic field which is formed so as to have a predetermined pattern for a current path through which a supplied current flows. The pattern includes portions formed close and parallel to each other so that magnetic fields induced by respective currents flowing through the portions can be cancelled with each other.
    Type: Grant
    Filed: December 23, 1988
    Date of Patent: June 30, 1992
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Shoei Kataoka, Hideo Nojima, Shuhei Tsuchimoto, Ryusuke Kita, Susumu Saitoh
  • Patent number: 5093622
    Abstract: An apparatus for determining the direction to and position of a buried conductor carrying an AC signal. The apparatus employs a unique antenna unit having upper and lower sensors, each sensor having two orthogonal solenoid coils. The signals from these coils, which are representative of the magnetic flux therethrough, are processed to yield corresponding digital values. The numbers are combined in a novel formula to yield a value which has been empirically found to be indicative of lateral postion. An appropriate display is controlled by the microprocessor according to the sign and magnitude of the positional value.
    Type: Grant
    Filed: March 17, 1989
    Date of Patent: March 3, 1992
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: William D. Balkman
  • Patent number: 5072181
    Abstract: In an angle position transmitter with a photoelectrically scannable transmitter disc and doubly supported transmitted shaft, the angle position transmitter determines the angle position of a rotary machine element so as to indicate absolute position with less than a full revolution. The measuring range is increased several times without adversely affecting the compact design of the angle position transmitter which is already limited by the need for a double support of the transmitter shaft. A magnet revolving with the transmitter shaft signals full revolutions of the transmitter shaft at a stationary magnetic field sensor. The full rotations are counted in a revolution counter. A sign is determined by the direction of motion. The magnet rotates in the dead space between two antifriction bearings of a transmitter shaft. The angle position transmitter is particularly well suited for use in machine tools, robots and motor vehicles.
    Type: Grant
    Filed: December 15, 1987
    Date of Patent: December 10, 1991
    Assignee: Siemens Aktiengesellschaft
    Inventor: Wilheim Burger
  • Patent number: 5053706
    Abstract: A SQUIDs magnetometer has three planar SQUID's which are fabricated on substrates mounted on three nonparallel surfaces of a member. Each SQUID is connected to a flux-locked loop drive circuit, and each SQUID has a main coil which is formed on the respective substrate and is threaded by the flux of an external magentic field which is being measured.
    Type: Grant
    Filed: June 29, 1988
    Date of Patent: October 1, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Norio Ohkawa
  • Patent number: 5015953
    Abstract: A magnetometer for detecting variations in a DC magnetic field. The magnetometer includes a magnetic field variation sensitive device that resonates at a characteristic resonant frequency by converting energy stored therein as a result of being excited by electromagnetic radiation at twice the resonant frequency when biased by a DC magnetic bias field within a predetermined field intensity range in which the amplitude of the resonance varies with variations of the field intensity.
    Type: Grant
    Filed: July 31, 1986
    Date of Patent: May 14, 1991
    Assignee: Security Tag Systems, Inc.
    Inventors: Lucian G. Ferguson, Lincoln H. Charlot, Jr.
  • Patent number: 4985681
    Abstract: For testing an interconnect network for shorts and interruptions, a point of the network to be tested is charged with a particle beam. Subsequently, a potential at least one further contact point is read with the same particle beam and an unaltered primary energy. An identification of potential occurs by documenting the secondary electrons triggered at the contact points. In order to avoid a disturbing change of potential during the measuring phase, the measuring time is only a fraction of the time for charging the network.
    Type: Grant
    Filed: December 27, 1985
    Date of Patent: January 15, 1991
    Assignee: Siemens Aktiengesellschaft
    Inventors: Matthias Brunner, Juergen Frosien, Reinhold Schmitt, Burkhard Lischke
  • Patent number: 4945307
    Abstract: A device for detecting irregularities in the surface of an object comprises at least one transducer which is movable relative to the surface of the object and an associated signal-processing unit which receives and processes output signals generated by the transducer. The signal-processing unit includes two electrical circuits, the first circuit providing a signal A which is derived from the output signal from the transducer and the second circuit including an analog shift register to provide a signal B which is derived from the output signal from the transducer and which is time delayed relative to signal A. The signal-processing unit also includes means for combining signals A and B to provide a measuring signal C.
    Type: Grant
    Filed: November 3, 1986
    Date of Patent: July 31, 1990
    Assignee: Tornbloms Kvalitetskontroll AB
    Inventor: Bengt Tornblom
  • Patent number: 4870360
    Abstract: When an electrically conducting material is subjected to an alternating magnetic field local changes in the magnetic field adjacent to the conducting material are detected by a detector comprising a magnetoresistor or Hall crystal which generate an electrical signal when subjected to the magnetic field.The process and apparatus can be used to identify, classify and locate electrically conductive material.The detectors can be of the order of a few millimeters in size and so can be used to detect local changes in the magnetic field over correspondingly small areas of the material.The invention is particularly useful in identifying coins used in coin operated machines.
    Type: Grant
    Filed: May 6, 1985
    Date of Patent: September 26, 1989
    Assignee: University College Cardiff Consulatants Limited
    Inventors: Alan J. Collins, Mazen R. Husni
  • Patent number: 4864239
    Abstract: An apparatus for the inspection of a stack of cylindrical objects such as roller bearings, uses an eddy current probe. The probe is positioned at an angle with respect to the surfaces of the objects in order to achieve an acceptable signal and then the objects are rotated while the probe is advanced along them to fully scan the surfaces.
    Type: Grant
    Filed: December 5, 1983
    Date of Patent: September 5, 1989
    Assignee: General Electric Company
    Inventors: Dominick A. Casarcia, Robert F. Feldman
  • Patent number: 4857851
    Abstract: In a pipeline through which a vehicle such as a pig is travelling, a magnetically activated detector detects the presence of the approaching pig and sends a signal to switch on a transmitter unit which supplies an alternating current to an AC coil. This generates a magnetic field for a preselected period, the flux signal being then sensed by a pair of crossed coil sensors on board the pig after which the signal is processed in a unit on-board the pig. A reference pulse is then output for recording on a tape recorder also on-board the pig. This technique enables a geographical reference of the vehicle to be fixed.
    Type: Grant
    Filed: January 29, 1985
    Date of Patent: August 15, 1989
    Assignee: British Gas Corporation
    Inventors: Donald W. Anderson, Charles W. Gregory
  • Patent number: 4725772
    Abstract: A self-contained unit intended primarily for tracing the circuit connection between electrical outlets and a circuit-breaking connection thereof to an AC power source. The unit includes a housing containing batteries, a buzzer or other sound-producing means, an AC relay and a switch for selective placement in either of two positions. An electrical cord extends from the housing and terminates in a male plug for insertion in a receptacle of the circuit to be traced. By placing the switch in its first position the buzzer will sound when the AC power is supplied to the receptacle; placing the switch in its second position will cause the buzzer to sound when AC power, initially present, is removed from the receptacle. A second embodiment adds to the foregoing the capability of testing unpowered circuits for continuity between two conductors by incorporating an additional selectively positioned switch.
    Type: Grant
    Filed: April 1, 1982
    Date of Patent: February 16, 1988
    Inventor: Rex W. Peak