Mutual Inductance Patents (Class 340/870.32)
  • Patent number: 8912887
    Abstract: An RFID tag comprising a coil and an RFID chip having two inputs/outputs, each input/output being connected to the coil. The tag further comprises an electrical circuit connected to the inputs/outputs, the circuit being adapted to operate in one of two modes, one mode outputting substantially no signal whereby the RFID chip is allowed to operate and a second mode being a mode wherein a signal is output so that the operation of the RFID-chip is interrupted. Alternatively, the circuit may have a lower operating voltage than the RFID-chip and may thus starve the RFID-chip and prevent its operation when desired.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: December 16, 2014
    Assignee: Cardlab APS
    Inventor: Finn Nielsen
  • Patent number: 8354941
    Abstract: An apparatus for determining and/or monitoring at least one process variable. The apparatus includes at least one, first electronics unit, at least one, second electronics unit, and at least one transferring unit. The transferring unit is arranged between the first electronics unit and the second electronics unit, and the transferring unit is embodied in such a manner, that it transmits electrical energy and data between the first electronics unit and the second electronics unit.
    Type: Grant
    Filed: October 15, 2007
    Date of Patent: January 15, 2013
    Assignee: Endress + Hasuer GmbH + Co. KG
    Inventors: Armin Wernet, Dirk Wiedmann
  • Patent number: 8102266
    Abstract: A transmitting and receiving apparatus (2) that transmits a radio signal to a capsule endoscope includes: a transmitting level determining unit (25) disposed near a transmitting resonance circuit (22); a frequency controller (26) that controls an oscillation frequency based on a result of determination executed by the transmitting level determining unit (25); and a frequency variable oscillator (16) that changes the oscillation frequency, based on the control of the frequency controller (26). By changing the oscillation frequency so that a transmission level becomes large, the oscillation frequency can be changed so as to decrease a frequency difference between the oscillation frequency and the resonance frequency of the resonance circuit (22) that changes along a variation in a self inductance value of a coil (24).
    Type: Grant
    Filed: January 21, 2005
    Date of Patent: January 24, 2012
    Assignee: Olympus Corporation
    Inventors: Hatsuo Shimizu, Takemitsu Honda, Masayuki Hashimoto, Kazutaka Nakatsuchi
  • Patent number: 8044822
    Abstract: The invention relates to a rotary transmitter for example for use in machine tools with adjusting tools. The rotary transmitter comprises a stator part (18) and a rotor part (26), each having a respective stator core part (72) and a rotor core part (74), which are separated from one another at mutually facing ends via an air gap, and each having at least one respective power winding (76, 78), which is wound on the stator core part and the rotor core part, in order to transmit power using the transformer principle, and having respective stator and rotor coupling turns (80?, 80?, 82?, 82?), which are associated with one another in pairs, for inductive data transmission. One aim of the invention is to transmit data without interference. A further aim is a low maintenance requirement.
    Type: Grant
    Filed: February 22, 2006
    Date of Patent: October 25, 2011
    Assignee: Komet Group GmbH
    Inventors: Roland Hoerl, Heiko Graf
  • Patent number: 7005967
    Abstract: A terminal for generating an electromagnetic field adapted to communicating with at least one transponder, and a method for controlling such a terminal including: an oscillating circuit adapted to being excited by a remote supply signal of the transponder; an amplitude demodulator for detecting possible data transmitted by the transponder; circuitry for regulating the signal phase in the terminal's oscillating circuit on a reference value; circuitry for measuring variables linked to the current in the oscillating circuit and to the voltage thereacross; and circuitry for comparing current values of these variables to predetermined values, to determine the presence of a transponder.
    Type: Grant
    Filed: May 11, 2001
    Date of Patent: February 28, 2006
    Assignee: STMicroelectronics S.A.
    Inventor: Luc Wuidart
  • Patent number: 6982651
    Abstract: An automatic meter reader module is provided that is adapted to be retrofitted or installed in a new or existing utility meter. The module includes a printed circuit board (PCB) on which is mounted on-board circuitry and detection equipment configured to detect utility consumption metered by the utility meter. A transmission device operatively coupled to the PCB is configured to transmit data indicative of utility usage. The PCB is configured to mount within an inner cavity of the utility meter.
    Type: Grant
    Filed: May 2, 2002
    Date of Patent: January 3, 2006
    Assignee: M & FC Holding, LLC
    Inventor: Jeffrey L. Fischer
  • Patent number: 6885310
    Abstract: Two A.C. output signals amplitude-modulated in accordance with two function values (sine and cosine) differing from each other in correspondence to a position-to-be-detected are received from a position sensor such as a resolver. By performing an addition or subtraction between a signal derived by shifting the electric phase of one of the received A.C. output signals by a predetermined angle, and the other received signal, two electric A.C. signals (sin(?t±d+?), sin((?t±d??)) are electrically synthesized which have electric phase angles (?) corresponding to the position-to-be-detected and are phase-shifted in opposite directions. “±d” here represents phase variation error caused by factors, other than the position-to-be-detected, such as temperature change. In the synthesized two signals, the phase variation errors (±d) appear in the same direction, while the phase differences (?) corresponding to the position are shifted in opposite, positive and negative, directions.
    Type: Grant
    Filed: March 3, 2003
    Date of Patent: April 26, 2005
    Inventors: Atsutoshi Goto, Yasuhiro Yuasa, Shuichi Tanaka, Nobuyuki Akatsu, Kazuya Sakamoto, Hiroshi Sakamoto, Akio Yamamoto
  • Patent number: 6720760
    Abstract: A scale loop formed by a loop trace of electrically conductive material is usable in an induced current position transducer. The scale loop is continuous and has a particular shape depending on the configuration of the induced current position transducer. The scale loop is not in contact with other highly conductive materials. The dimensions of the cross-section of the conducting trace are chosen to increase the transfer of energy through the transducer.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: April 13, 2004
    Assignee: Mitutoyo Corporation
    Inventor: Michelle M. Milvich
  • Publication number: 20040036469
    Abstract: An encoder (10) for a nanopostioner (24) includes a strip of magnetic bits (18) for producing discrete magnetic fields and a giant magnetoresistor (GMR) (14) which changes in electrical resistance in response to changes in the magnetic fields. The GMR (14) is connected to a mass (12) which moves along a path proximate to the strip of magnetic bits (18). A voltage sensor (20) is connected to the GMR (14) to produce digital signals based on the changes in electrical resistance of the GMR (14). A processor (22) calculates the position of the nanopositioner (24) based on the digital signals.
    Type: Application
    Filed: August 28, 2003
    Publication date: February 26, 2004
    Inventor: David P. Fries
  • Patent number: 6636035
    Abstract: In an electronic caliper, a detecting circuit 112 detects displacement of a grid with respect to a scale, on the basis of a signal from a transducer 110. A CPU 114 displays the detected position on a display device 124. The CPU 114 performs error detection on the transducer, only when the relative speed of the grid with respect the scale is zero, or becomes equal to or smaller than a predetermined value. Since error detection is performed only at a predetermined timing, power consumption can be reduced.
    Type: Grant
    Filed: March 13, 2001
    Date of Patent: October 21, 2003
    Assignee: Mitutoyo Corporation
    Inventors: Tetsuro Kiriyama, Toshiharu Miyata, Nobuyuki Hayashi, Kouji Sasaki, Yoshiaki Shiraishi
  • Patent number: 6628115
    Abstract: A electromagnetic induction-type absolute position transducer according to the present invention has a plurality of scale loops functioning as coils. The scale loop has first and second loop portions and a connecting pattern portion which connects the corresponding first and second loop portions with each other. The first and second loop portions are arranged along the measuring axis at different wavelength intervals. At least part of the pattern widths constituting scale loops are gradually increased as the length of a connecting pattern portion becomes longer.
    Type: Grant
    Filed: January 22, 2002
    Date of Patent: September 30, 2003
    Assignee: Mitutoyo Corporation
    Inventors: Kouji Sasaki, Yoshiaki Shiraishi, Nobuyuki Hayashi
  • Publication number: 20030179103
    Abstract: A vibration transducer such as a geophone, comprising a central pole piece (110) with a magnet (112) and coil (118) concentrically arranged around it. The position of the magnet (112) is fixed relative to the pole piece (110) and the coil (118) is movable relative to the magnet (112). A method of manufacturing a vibration transducer is characterised in that a bobbin carrying the coils is formed from a substantially tubular body which is positioned on a mandrel and at least one coil is wound around its outer surface, the mandrel being removed from the bobbin when the coil is complete. Another method is characterised in that the coil is formed separately and the bobbin is formed from a substantially tubular body which is positioned inside the coil and expanded to contact the coil when in position.
    Type: Application
    Filed: February 12, 2003
    Publication date: September 25, 2003
    Inventor: Masahiro Kamata
  • Publication number: 20030146849
    Abstract: Two A.C. output signals amplitude-modulated in accordance with two function values (sine and cosine) differing from each other in correspondence to a position-to-be-detected are received from a position sensor such as a resolver. By performing an addition or subtraction between a signal derived by shifting the electric phase of one of the received A.C. output signals by a predetermined angle, and the other received signal, two electric A.C. signals (sin(&ohgr;t±d+&thgr;), sin((&ohgr;t±d−&thgr;)) are electrically synthesized which have electric phase angles (&thgr;) corresponding to the position-to-be-detected and are phase-shifted in opposite directions. “±d” here represents phase variation error caused by factors, other than the position-to-be-detected, such as temperature change.
    Type: Application
    Filed: March 3, 2003
    Publication date: August 7, 2003
    Applicant: Atsutoshi GOTO
    Inventors: Atsutoshi Goto, Yasuhiro Yuasa, Shuichi Tanaka, Nobuyuki Akatsu, Kazuya Sakamoto, Hiroshi Sakamoto, Akio Yamamoto
  • Patent number: 6593730
    Abstract: A position sensor for determining a set position thereof is disclosed. The sensor comprises a time-varying magnetic field generator. A movable electrically conductive element is positioned such that the time-varying magnetic field generates eddy currents therein. At least one pick-up is provided for generating a signal in response to the time-varying magnetic field. Movement of the conductive element relative to the pick-up alters the magnetic coupling between the magnetic field generator and the pick-up allowing the set position to be determined unambiguously.
    Type: Grant
    Filed: June 21, 2001
    Date of Patent: July 15, 2003
    Assignee: Cherry GmbH
    Inventor: Martin Zapf
  • Patent number: 6573707
    Abstract: A scale and a detecting head each include input/output connectors. Either of the input/output connectors is connected to receiving-side connector. By connecting the receiving-side connector to either of the scale and the detecting head, which is fixed in use, there is no change that a receiving-side cable will be disconnected by movement of the counterpart of the fixed member. This results in improvement of the reliability. Additionally, device is operable at high speed since the cable does not restrict motion of the movable member.
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: June 3, 2003
    Assignee: Mitutoyo Corporation
    Inventors: Tetsuro Kiriyama, Toshitaka Shimomura
  • Patent number: 6552666
    Abstract: Two A.C. output signals amplitude-modulated in accordance with two function values (sine and cosine) differing from each other in correspondence to a position-to-be-detected are received from a position sensor such as a resolver. By performing an addition or subtraction between a signal derived by shifting the electric phase of one of the received A.C. output signals by a predetermined angle, and the other received signal, two electric A.C. signals (sin(&ohgr;t±d+&thgr;), sin(&ohgr;t±d−&thgr;)) are electrically synthesized which have electric phase angles (&thgr;) corresponding to the position-to-be-detected and are phase-shifted in opposite directions. “±d” here represents phase variation error caused by factors, other than the position-to-be-detected, such as temperature change.
    Type: Grant
    Filed: January 6, 2000
    Date of Patent: April 22, 2003
    Inventors: Atsutoshi Goto, Yasuhiro Yuasa, Shuichi Tanaka, Nobuyuki Akatsu, Kazuya Sakamoto, Hiroshi Sakamoto, Akio Yamamoto
  • Patent number: 6545461
    Abstract: An electromagnetic induction position detector has a detection head and a scale which are placed so as to be opposed to each other with a predetermined gap in a relatively movable manner. The detection head has a driving coil which generates a primary varying magnetic flux, and a receiving coil which detects a magnetic pattern changed in a predetermined spatial period and in a direction of the relative movement. The scale 2 has a magnetic modulating section which modulates the primary varying magnetic flux to generate the magnetic pattern. The scale 2 has a plate-shaped resin substrate 30. Metal foil 61 of a predetermined pattern which prevents the resin substrate 30 from being expanded or contracted, and suppresses an eddy current formed on a face of the scale opposite to a face on which the magnetic modulating section is formed.
    Type: Grant
    Filed: March 12, 2001
    Date of Patent: April 8, 2003
    Assignee: Mitutoyo Corporation
    Inventor: Toshiharu Miyata
  • Patent number: 6531873
    Abstract: A supplementary device, such as a charging, cleaning and/or diagnosis device, for a small electric device, such as an electric hair cutting or hair removal apparatus or an electric toothbrush, but particularly for an electric shaving apparatus, includes an arrangement to detect whether it is connected electrically and/or magnetically to the small electric device, and an arrangement to discriminate between different types of small electric device. This arrangement monitors an electric and/or magnetic quantity prevailing at the connection of the supplementary device. A method for detecting the presence of an electric and/or magnetic connection between said devices includes monitoring an electric and/or magnetic quantity prevailing at the connection of the supplementary device.
    Type: Grant
    Filed: May 4, 2000
    Date of Patent: March 11, 2003
    Assignee: Braun GmbH
    Inventor: Frank Wohlrabe
  • Patent number: 6522128
    Abstract: A transducer is provided for use in a position sensor which senses the position of two relatively movable members. In one form, the transducer has a plurality of sensor windings having a number of loops arranged in succession and connected in series so that signals induced in adjacent loops by a common electromagnetic field oppose each other and an excitation winding having at least one loop super-imposed on but electrically isolated from the loops of the sensor windings.
    Type: Grant
    Filed: June 8, 2000
    Date of Patent: February 18, 2003
    Assignee: Synaptics (UK) Limited
    Inventors: David T. F. Ely, Andrew N. Dames
  • Patent number: 6486796
    Abstract: A detect ion unit 10, which is disposed in opposite relation to a scale 12, includes a transmission coil 10a and a detection coil 10b. A metal film 10g formed of two opposing metal films is provided between a silicon substrate and the transmission coil 10a, one of the two metal films is connected to a drive circuit 10c, and the other is connected to the transmission coil 10a. The metal film 10g provides the capacitance C of an LC resonance circuit, so that a chip capacitor is made unnecessary. The metal film 10g may be formed of a magnetic material.
    Type: Grant
    Filed: July 11, 2001
    Date of Patent: November 26, 2002
    Assignee: Mitutoyo Corporation
    Inventor: Toshiharu Miyata
  • Publication number: 20020135497
    Abstract: A non-contact type displacement sensor is provided with a housing, a rotational shaft being in an approximately cylindrical hollow shape, a magnetic circuit forming member disposed in an inner space of the rotational shaft, and a magnetic sensing element supported by a housing so as to be positioned on a central axis of the rotational shaft in a space enclosed by the magnetic circuit forming member, wherein the magnetic sensing element is not displaced.
    Type: Application
    Filed: March 22, 2002
    Publication date: September 26, 2002
    Inventors: Masahiro Kimura, Keiji Yasuda, Kiyohiro Fukaya
  • Patent number: 6400138
    Abstract: A reduced offset absolute position transducer has at least one magnetic field generator that generates a first changing magnetic flux in a first flux region. A plurality of coupling loops have a first plurality of coupling loop portions spaced at a first wavelength along a measuring axis and a second plurality of coupling loop portions spaced at a second wavelength along a measuring axis. One of the first plurality of coupling loop portions and the second plurality of coupling loop portions are inductively coupled to a first changing magnetic flux from a transmitter winding in a first flux region to generate a second changing magnetic flux outside the first flux region in the other of the first plurality of coupling loop portions and the second plurality of coupling loop portions. A magnetic flux sensor is positioned outside the first flux region and is responsive to the second changing magnetic flux to generate a position-dependent output signal.
    Type: Grant
    Filed: October 20, 1999
    Date of Patent: June 4, 2002
    Assignee: Mitutoyo Corporation
    Inventor: Nils Ingvar Andermo
  • Patent number: 6335618
    Abstract: A high-accuracy inductive absolute position transducer system has two members movable relative to each other and includes an amplitude modulating transducer including flux modulators of progressively varying properties. The amplitude modulating transducer includes a transmitter winding and at least one set of receiver windings. An amplitude modulating transducer has a plurality of flux modulator zones distributed along the measuring axis. Flux modulators are formed in at least some of the flux modulator zones. The properties of different flux modulators are varied so as to generate varied flux. A signal generating and processing circuit is connected to the transmitter winding. The flux modulators modulate the inductive coupling based on the relative position between the read head member and the scale member.
    Type: Grant
    Filed: October 5, 1999
    Date of Patent: January 1, 2002
    Assignee: Mitutoyo Corporation
    Inventor: Michael Nahum
  • Patent number: 6329813
    Abstract: An inductive absolute position sensor has at least one magnetic field generator that generates a first changing magnetic flux in a first flux region. A plurality of coupling loops have a first plurality of coupling loop portions spaced at an interval related to a first wavelength along a measuring axis and a second plurality of coupling loop portions spaced at an interval related to a second wavelength along a measuring axis. One of the first plurality of coupling loop portions and the second plurality of coupling loop portions are inductively coupled to a first changing magnetic flux from a transmitter winding in a first flux region to generate a second changing magnetic flux outside the first flux region in the other of the first plurality of coupling loop portions and the second plurality of coupling loop portions. A magnetic flux sensor is positioned outside the first flux region and is responsive to the second changing magnetic flux to generate a position-dependent output signal.
    Type: Grant
    Filed: December 17, 1998
    Date of Patent: December 11, 2001
    Assignee: Mitutoyo Corporation
    Inventor: Nils Ingvar Andermo
  • Patent number: 6313624
    Abstract: A position sensor, such as a rotary position sensor, includes the signal-conditioning electronics in the housing. The signal-conditioning electronics are disposed on a printed wiring board, which is assembled with another printed wiring board including the sensor windings to provide a sub-assembly. A mu-metal shield is interposed between the printed wiring boards to prevent magnetic interference. The sub-assembly is disposed in the sensor housing adjacent to an inductor board which turns on a shaft. The inductor board emanates an internally or externally generated excitation signal that induces a signal in the sensor windings. The induced signal represents the rotary position of the inductor board relative to the sensor winding board.
    Type: Grant
    Filed: November 27, 1998
    Date of Patent: November 6, 2001
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Dean C. Alhorn, David E. Howard, Dennis A. Smith
  • Patent number: 6304825
    Abstract: A rotary encoder error compensation system for use in a marking device with a rotary encoder includes an error correction logic circuit and an error correction table linked to the error correction logic circuit. The rotary encoder is configured to generate an encoder signal indicating a detected position of a rotating element and has a known rotary encoder error. The error correction logic circuit receives the encoder signal from the rotary encoder. The error correction table includes normalized error correction values. The error correction logic circuit accesses the error correction table based on the detected position of the rotating element and the known rotary encoder error and obtains one of the normalized error correction values corresponding to the detected position of the rotating element and the known rotary encoder error.
    Type: Grant
    Filed: January 19, 1999
    Date of Patent: October 16, 2001
    Assignee: Xerox Corporation
    Inventors: William J. Nowak, Kevin M. Carolan, Michael R. Furst, Orlando J. Lacayo
  • Patent number: 6271661
    Abstract: An absolute position transducer system has two members movable relative to each other and includes a code track transducer and at least one fine wavelength transducer. The code track is arranged to form a sequential pattern of base-N code words, where N is greater than two (i.e., non-binary). Each sequential non-binary code word identifies an absolute position of one member with respect to the other at a first resolution. Alternatively, the code track is arranged to form a pseudo-random non-binary code word pattern. In this case, the transducer system compares a non-binary code word with a look-up table to determine an absolute position of one member with respect to the other at a first resolution. In order to generate a non-binary code word pattern, code track transducer employs different-sized flux disrupters, different-sized flux enhancers, or a combination of flux disrupters and enhancers.
    Type: Grant
    Filed: March 16, 1999
    Date of Patent: August 7, 2001
    Assignee: Mitutoyo Corporation
    Inventors: Nils Ingvar Andermo, Karl G. Masreliez, Kurt E. Steinke
  • Patent number: 6259249
    Abstract: An inductive linear encoder (10) has a position sensor (1) and scale (2) which are movably disposed relative to each other. The sensor (1) is with a drive wire (3) to which an alternating current is supplied, and one set of detection wires (4a-4d) at right angles to the drive wire (3) in the same plane. The scale (2) is configured including an elongate substrate (7) having its surface on which a series combination of conductive closed loop patterns (8) are periodically arranged at equal intervals. These conductive closed loop (8) are linearly laid out on the substrate (7) in the relative movement direction. Each loop (8) consists essentially of a reception conductor segment (8a) and signal transmit conductor segments (8b, 8c) integral with the former (8a). The receive conductor segment (8a) is responsible for generation of an induced current due to a first variable magnetic field creatable from the drive coil (3).
    Type: Grant
    Filed: November 23, 1998
    Date of Patent: July 10, 2001
    Assignee: Mitutoyo Corporation
    Inventor: Toshiharu Miyata
  • Patent number: 6255810
    Abstract: A redundant inductive angle sensor has two LC oscillators of at least approximately identical design. By inductively coupling the oscillators, the oscillators synchronize themselves with respect to frequency and phase relationship so that undesirable mutual interference is prevented. This provides an inductive angle sensor, which is able to function even if one of the LC oscillators becomes inoperative.
    Type: Grant
    Filed: September 4, 1998
    Date of Patent: July 3, 2001
    Assignee: Hella KG Hueck & Co.
    Inventors: Henning Irle, Norbert Kost, Franz-Josef Schmidt
  • Patent number: 6236199
    Abstract: An inductive angle sensor includes: a stator element having an exciting coil with a periodic AC voltage applied thereto and several receiving coils; a rotor element that affects a strength of inductive coupling between the exciting coil and receiving coils as a function of its angular position relative to the stator element; and an evaluation circuit for determining an angular position of the rotor element relative to the stator element from voltage signals induced in the receiving coils. The rotor element forms at least one closed-loop lead that, at least over a partial area, forms a periodic repeating bend structure in a direction of a circumference of the rotor element. The inductive angle sensor provides a compact structure, a high resolution, and a particularly high degree of insensitivity to production and installation tolerances.
    Type: Grant
    Filed: September 4, 1998
    Date of Patent: May 22, 2001
    Assignee: Hella KG Hueck & Co.
    Inventors: Henning Irle, Norbert Kost, Franz-Josef Schmidt