MX155372A - Mejoras a sistema inductivo de acoplamiento para transmision bi-direccional de datos digitales - Google Patents

Mejoras a sistema inductivo de acoplamiento para transmision bi-direccional de datos digitales

Info

Publication number
MX155372A
MX155372A MX201714A MX20171484A MX155372A MX 155372 A MX155372 A MX 155372A MX 201714 A MX201714 A MX 201714A MX 20171484 A MX20171484 A MX 20171484A MX 155372 A MX155372 A MX 155372A
Authority
MX
Mexico
Prior art keywords
digital data
inductive coupling
coupling system
directional transmission
directional
Prior art date
Application number
MX201714A
Other languages
English (en)
Inventor
Felice M Sciulli
Original Assignee
Rockwell International Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Rockwell International Corp filed Critical Rockwell International Corp
Publication of MX155372A publication Critical patent/MX155372A/es

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B5/00Near-field transmission systems, e.g. inductive or capacitive transmission systems
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01DMEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D4/00Tariff metering apparatus
    • G01D4/002Remote reading of utility meters
    • G01D4/006Remote reading of utility meters to a non-fixed location, i.e. mobile location
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06MCOUNTING MECHANISMS; COUNTING OF OBJECTS NOT OTHERWISE PROVIDED FOR
    • G06M1/00Design features of general application
    • G06M1/27Design features of general application for representing the result of count in the form of electric signals, e.g. by sensing markings on the counter drum
    • GPHYSICS
    • G08SIGNALLING
    • G08CTRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS
    • G08C17/00Arrangements for transmitting signals characterised by the use of a wireless electrical link
    • G08C17/04Arrangements for transmitting signals characterised by the use of a wireless electrical link using magnetically coupled devices
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B5/00Near-field transmission systems, e.g. inductive or capacitive transmission systems
    • H04B5/20Near-field transmission systems, e.g. inductive or capacitive transmission systems characterised by the transmission technique; characterised by the transmission medium
    • H04B5/24Inductive coupling
    • H04B5/26Inductive coupling using coils
    • H04B5/266One coil at each side, e.g. with primary and secondary coils
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B5/00Near-field transmission systems, e.g. inductive or capacitive transmission systems
    • H04B5/40Near-field transmission systems, e.g. inductive or capacitive transmission systems characterised by components specially adapted for near-field transmission
    • H04B5/45Transponders
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B90/00Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02B90/20Smart grids as enabling technology in buildings sector
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y04INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04SSYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S20/00Management or operation of end-user stationary applications or the last stages of power distribution; Controlling, monitoring or operating thereof
    • Y04S20/30Smart metering, e.g. specially adapted for remote reading

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Theoretical Computer Science (AREA)
  • Arrangements For Transmission Of Measured Signals (AREA)
  • Near-Field Transmission Systems (AREA)
  • Bidirectional Digital Transmission (AREA)
MX201714A 1983-06-20 1984-06-19 Mejoras a sistema inductivo de acoplamiento para transmision bi-direccional de datos digitales MX155372A (es)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US06/505,032 US4758836A (en) 1983-06-20 1983-06-20 Inductive coupling system for the bi-directional transmission of digital data

Publications (1)

Publication Number Publication Date
MX155372A true MX155372A (es) 1988-02-23

Family

ID=24008725

Family Applications (1)

Application Number Title Priority Date Filing Date
MX201714A MX155372A (es) 1983-06-20 1984-06-19 Mejoras a sistema inductivo de acoplamiento para transmision bi-direccional de datos digitales

Country Status (7)

Country Link
US (1) US4758836A (es)
EP (1) EP0131732B1 (es)
JP (1) JPH0640631B2 (es)
AU (1) AU567743B2 (es)
CA (1) CA1246178A (es)
DE (1) DE3483123D1 (es)
MX (1) MX155372A (es)

Families Citing this family (65)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4782341A (en) * 1983-07-01 1988-11-01 Rockwell International Corporation Meter data gathering and transmission system
GB2167586A (en) * 1984-11-12 1986-05-29 Halpern John Wolfgang Card reader
DE3500816A1 (de) * 1985-01-11 1986-07-17 Gewerkschaft Eisenhütte Westfalia, 4670 Lünen Ausbausteuergeraet fuer elektrohydraulische ausbausteuerungen
JPH0681083B2 (ja) * 1985-08-15 1994-10-12 オムロン株式会社 非接触式デ−タ交信装置
JPH0815265B2 (ja) * 1985-08-16 1996-02-14 オムロン株式会社 非接触式応答ユニット
DE3787291T2 (de) * 1986-01-13 1994-04-21 Abbott Lab Verfahren und Vorrichtung zur Speicherung und zur Wiedergewinnung elektronischer Daten.
DE252184T1 (de) * 1986-06-05 1988-07-21 Rockwell International Corp., Pittsburgh, Pa., Us Zaehlerablesung durch einen grubendeckel.
NL8700861A (nl) * 1987-04-13 1988-11-01 Nedap Nv Lees-, schrijfsysteem met miniatuur informatiedrager.
FR2624329B1 (fr) * 1987-12-08 1990-03-09 Crouzet Sa Procede et dispositif de transmission magnetique de donnees numeriques
CH674287A5 (es) * 1988-01-21 1990-05-15 Koechler Erika Fa
DE3804592C1 (en) * 1988-02-13 1989-08-03 Spanner-Pollux Gmbh, 6700 Ludwigshafen, De Remote read-out system for consumption meter (electricity meter, supply meter)
GB8904644D0 (en) * 1989-03-01 1989-04-12 Raytel Group The Limited Electromagnetic communication interface
EP0518916B1 (en) * 1990-02-21 1997-07-30 Rosemount Inc. Multifunction isolation transformer
US5155481A (en) * 1990-05-25 1992-10-13 Schlumberger Industries, Inc. Two and three wire utility data communications system
US5252967A (en) * 1990-05-25 1993-10-12 Schlumberger Industries, Inc. Reader/programmer for two and three wire utility data communications system
US5243338A (en) * 1990-05-25 1993-09-07 Schlumberger Industries, Inc. Two and three wire utility data communications system
GB2247318B (en) * 1990-08-20 1994-08-10 Rosemount Ltd A transmitter
US5574441A (en) * 1990-12-19 1996-11-12 Cubic Automatic Revenue Collection Group Mass transit inductive data communication system
JPH05101293A (ja) * 1991-10-07 1993-04-23 Yamatake Honeywell Co Ltd 遠隔データ読み取り方法
US5325046A (en) * 1991-12-18 1994-06-28 Apple Computer, Inc. Inductive wireless data connection
US5229652A (en) * 1992-04-20 1993-07-20 Hough Wayne E Non-contact data and power connector for computer based modules
US5343906A (en) * 1992-05-15 1994-09-06 Biodigital Technologies, Inc. Emisson validation system
US5298894A (en) * 1992-06-17 1994-03-29 Badger Meter, Inc. Utility meter transponder/antenna assembly for underground installations
WO1994011851A1 (de) * 1992-11-10 1994-05-26 Micro-Sensys Gmbh Miniaturisierter telemetriebaustein
GB9305603D0 (en) * 1993-03-18 1993-05-05 Thames Water Utilities Data transmission
US5619192A (en) * 1994-06-14 1997-04-08 Logicon, Inc. Apparatus and method for reading utility meters
US6472975B1 (en) 1994-06-20 2002-10-29 Avid Marketing, Inc. Electronic identification system with improved sensitivity
US6181257B1 (en) 1994-09-29 2001-01-30 Kemp-Meek Manufacturing, Inc. Universal utility usage data gathering system
US5602744A (en) * 1994-09-29 1997-02-11 Meek; Jean L. Universal send/receive utility usage data gathering system
US5659300A (en) * 1995-01-30 1997-08-19 Innovatec Corporation Meter for measuring volumetric consumption of a commodity
US5856791A (en) * 1996-06-04 1999-01-05 M&Fc Holding Company, Inc. Port expander for utility meter reading
US5825302A (en) * 1996-11-20 1998-10-20 Texas Instruments Incorporated System and method for transmitting data using reflected electromagnetic radiation
AU8256398A (en) 1997-06-13 1998-12-30 Itron Inc. Telemetry antenna system
US20080129538A1 (en) * 1999-02-23 2008-06-05 Raj Vaswani Electronic electric meter for networked meter reading
US6538577B1 (en) * 1997-09-05 2003-03-25 Silver Springs Networks, Inc. Electronic electric meter for networked meter reading
WO1999022548A2 (en) 1997-10-24 1999-05-06 Itron, Inc. Passive radiator
GB9912559D0 (en) * 1999-05-28 1999-07-28 Fusion Meters Ltd Meter reader
US6222443B1 (en) 2000-04-24 2001-04-24 Robert D. Beeson Quick reliable power and/or data transfer system between tow vehicle and trailer via hitch and hitch receiver coupling
DE10054740A1 (de) * 2000-11-04 2002-05-16 Rheintacho Messtechnik Gmbh Schaltungsanordnung und Verfahren zum Betreiben eines Meßwertaufnehmers
GB0030661D0 (en) * 2000-12-15 2001-01-31 Flight Refueling Ltd Coupling signals to flowlines
FR2823339A1 (fr) * 2001-04-04 2002-10-11 St Microelectronics Sa Circuit integre sans contact comprenant un circuit anticollision a logique cablee
US6622097B2 (en) * 2001-06-28 2003-09-16 Robert R. Hunter Method and apparatus for reading and controlling electric power consumption
US7039532B2 (en) * 2001-06-28 2006-05-02 Hunter Robert R Method and apparatus for reading and controlling utility consumption
JP4125160B2 (ja) * 2003-03-06 2008-07-30 キヤノン株式会社 送信装置および受信装置
US7071838B2 (en) * 2003-05-02 2006-07-04 Potentia Semiconductor, Inc. Coupling signals via a coupling arrangement
US6917226B2 (en) * 2003-05-02 2005-07-12 Potentia Semiconductor, Inc. Transformer coupling arrangement and method using a plurality of drivers
US6911746B2 (en) * 2003-05-02 2005-06-28 Potentia Semiconductor, Inc. Signal and power transformer coupling arrangements
US20050087424A1 (en) * 2003-09-22 2005-04-28 Cubic Corporation Mass transit bus fare box
US7346483B2 (en) * 2003-10-10 2008-03-18 Synopsys, Inc. Dynamic FIFO for simulation
US20050224313A1 (en) * 2004-01-26 2005-10-13 Cubic Corporation Robust noncontact media processor
JP4836007B2 (ja) * 2004-04-01 2011-12-14 コンティ テミック マイクロエレクトロニック ゲゼルシャフト ミット ベシュレンクテル ハフツング 制御装置と車輪モジュールとの間の伝送方法及び装置
KR100833512B1 (ko) * 2006-12-08 2008-05-29 한국전자통신연구원 태그의 센싱 데이터 저장 장치 및 그 방법
US20090222338A1 (en) * 2008-03-03 2009-09-03 Hamilton Ii Rick A Monitoring and Rewards Methodologies for "Green" Use of Vehicles
US9151654B2 (en) * 2011-04-26 2015-10-06 Sensus Usa Inc. Method and apparatus for capturing energy from a meter reading device
US8640964B2 (en) 2011-06-01 2014-02-04 International Business Machines Corporation Cartridge for storing biosample plates and use in automated data storage systems
US9417237B2 (en) 2011-06-01 2016-08-16 International Business Machines Corporation Biosample plate with data storage and wireless communication means
US9286914B2 (en) 2011-06-01 2016-03-15 International Business Machines Corporation Cartridge for storing biosample capillary tubes and use in automated data storage systems
US9110108B2 (en) * 2012-05-04 2015-08-18 Landis+Gyr, Inc. Power management arrangement and method in a utility meter
US9250254B2 (en) 2012-09-30 2016-02-02 International Business Machines Corporation Biosample cartridge with radial slots for storing biosample carriers and using in automated data storage systems
US20140327553A1 (en) * 2013-05-03 2014-11-06 Cypress Semiconductor Corporation Zero power metering circuits, systems and methods
WO2015121113A1 (en) 2014-02-14 2015-08-20 Koninklijke Philips N.V. Transformer for providing feeding and data signals
EP3029431A1 (de) * 2014-12-04 2016-06-08 GWF MessSysteme AG Zähler und Verfahren zur Ermittlung von Zählerständen und Verfahren zur drahtlosen Übertragung von elektrischer Energie
US11536754B2 (en) 2019-08-15 2022-12-27 Landis+Gyr Innovations, Inc. Electricity meter with fault tolerant power supply
CN112903046A (zh) 2019-11-19 2021-06-04 卡姆鲁普股份有限公司 模块化超声耗量表
CN111384770B (zh) * 2020-04-28 2023-03-24 天津智模科技有限公司 隔离型双向缓冲电路及缓冲器

Family Cites Families (51)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1024735A (en) * 1963-07-05 1966-04-06 Gen Electric Co Ltd Improvements in or relating to identification systems
GB1097174A (en) * 1965-05-04 1967-12-29 Smidth & Co As F L Improvements relating to methods and apparatus for transferring data from rotary bodies
US3441923A (en) * 1966-01-10 1969-04-29 Anadasko Production Co Automated meter reading system
GB1253826A (en) * 1968-08-13 1971-11-17 Parkinson Cowan Appliances Ltd Improvements in or relating to remote reading means
US3569833A (en) * 1968-12-20 1971-03-09 Gen Electric Resonant ring coupling communications system
US3656112A (en) * 1969-03-14 1972-04-11 Constellation Science And Tech Utility meter remote automatic reading system
CA878140A (en) * 1969-05-12 1971-08-10 S. Mackelvie John Signal transmitting system for rotating apparatus
CH501898A (de) * 1969-06-06 1971-01-15 Patelhold Patentverwertung Einrichtung zur Präzisionsmessung der Schieberbewegung in relativ zu einem stationären Teil rotierenden Planscheiben, insbesondere für Werkzeugmaschinensteuerungen
US3662758A (en) * 1969-06-30 1972-05-16 Mentor Corp Stimulator apparatus for muscular organs with external transmitter and implantable receiver
US3689885A (en) * 1970-09-15 1972-09-05 Transitag Corp Inductively coupled passive responder and interrogator unit having multidimension electromagnetic field capabilities
US3872455A (en) * 1971-11-17 1975-03-18 Monitron Ind Physiological measurement display system
US3781792A (en) * 1972-01-03 1973-12-25 British Railways Board Error detection in communication system by repetition of data
US3748654A (en) * 1972-01-21 1973-07-24 Rockwell Mfg Co Remote meter read-out station with pull-off cover
US3806904A (en) * 1972-01-21 1974-04-23 Rockwell Mfg Co Remote meter read-out apparatus
US3840866A (en) * 1973-02-08 1974-10-08 Textron Inc Meter reading
US3852726A (en) * 1973-07-26 1974-12-03 Ram Domestic Prod Co Remote meter monitor
GB1488304A (en) * 1974-06-20 1977-10-12 Yukogawa Electric Works Ltd Signal transmission system
US4085287A (en) * 1975-12-19 1978-04-18 Neptune Water Meter Company Data transmitting apparatus
SE396249B (sv) * 1976-01-13 1977-09-12 Asea Ab Beroringsfri signaloverforing
US4077030A (en) * 1976-02-19 1978-02-28 The Bendix Corporation Sensor data input by means of analog to pulse width-to digital converter
US4119948A (en) * 1976-04-29 1978-10-10 Ernest Michael Ward Remote meter reading system
GB1589748A (en) * 1976-09-10 1981-05-20 Matsushita Electric Works Ltd Time division multiplex transmission system
US4132981A (en) * 1976-10-21 1979-01-02 Rockwell International Corporation Self-powered system for measuring and storing consumption of utility meter
DE2812896C2 (de) * 1977-03-28 1983-10-27 Ricoh Co., Ltd., Tokyo Datenerfassungseinrichtung
US4206449A (en) * 1977-07-27 1980-06-03 American District Telegraph Company Multiple sensor intrusion alarm system
US4187854A (en) * 1977-10-17 1980-02-12 Medtronic, Inc. Implantable demand pacemaker and monitor
JPS5951793B2 (ja) * 1978-06-08 1984-12-15 株式会社リコー デ−タ収集方式
US4361838A (en) * 1978-07-29 1982-11-30 Ricoh Co., Ltd. Remote meter reading arrangement
US4223830A (en) * 1978-08-18 1980-09-23 Walton Charles A Identification system
US4237900A (en) * 1979-02-14 1980-12-09 Pacesetter Systems, Inc. Implantable calibration means and calibration method for an implantable body transducer
US4223679A (en) * 1979-02-28 1980-09-23 Pacesetter Systems, Inc. Telemetry means for tissue stimulator system
US4236068A (en) * 1979-03-29 1980-11-25 Walton Charles A Personal identification and signaling system
US4338601A (en) * 1979-06-28 1982-07-06 Nance Kivell S Apparatus for the storage and transfer of information
US4333072A (en) * 1979-08-06 1982-06-01 International Identification Incorporated Identification device
DE2936439C2 (de) * 1979-09-08 1983-02-17 Wabco Westinghouse Fahrzeugbremsen GmbH, 3000 Hannover Anordnung zur asynchronen Übertragung von digitalen Radgeschwindigkeits-Meßwerten
US4349821A (en) * 1980-01-28 1982-09-14 Westinghouse Electric Corp. Data acquisition system and analog to digital converter therefor
US4355361A (en) * 1980-02-06 1982-10-19 Sangamo Weston, Inc. Data processor apparatus for multitariff meter
US4345146A (en) * 1980-03-25 1982-08-17 Story James R Apparatus and method for an electronic identification, actuation and recording system
US4354190A (en) * 1980-04-04 1982-10-12 General Electric Company Rotor measurement system using reflected load transmission
SU1068051A3 (ru) * 1980-05-19 1984-01-15 Таг Радионикс Лимитед (Фирма) Устройство дл передачи и приема сигналов
US4384228A (en) * 1980-12-18 1983-05-17 Hewlett-Packard Company Acousto-electric transducer
DE3107928A1 (de) * 1981-03-02 1982-09-16 Vdo Adolf Schindling Ag, 6000 Frankfurt Einrichtung zum beruehrungslosen uebertragen eines zahlenwertes
US4439764A (en) * 1981-04-09 1984-03-27 Westinghouse Electric Corp. Dual mode meter reading apparatus
IL63502A (en) * 1981-08-04 1984-10-31 Mahanaim Diuk Hydraulica Apparatus for identification of animals
US4388524A (en) * 1981-09-16 1983-06-14 Walton Charles A Electronic identification and recognition system with code changeable reactance
US4463354A (en) * 1981-12-09 1984-07-31 Sears Lawrence M Apparatus for communicating utility usage related information from a utility usage location to a portable utility usage registering device
FR2518335A1 (fr) * 1981-12-14 1983-06-17 Charbonnages De France Procede et dispositif de teletransmission de signaux et application a la detection et/ou la mesure de la teneur en gaz combustible d'une atmosphere
US4473825A (en) * 1982-03-05 1984-09-25 Walton Charles A Electronic identification system with power input-output interlock and increased capabilities
US4510495A (en) * 1982-08-09 1985-04-09 Cornell Research Foundation, Inc. Remote passive identification system
US4532416A (en) * 1983-01-03 1985-07-30 Patrick Berstein Transaction terminal with simplified data entry
GB2138609A (en) * 1983-04-19 1984-10-24 Emi Ltd Electronic counter for mechanical drive

Also Published As

Publication number Publication date
AU567743B2 (en) 1987-12-03
EP0131732A2 (en) 1985-01-23
DE3483123D1 (de) 1990-10-11
EP0131732A3 (en) 1987-04-29
AU2914284A (en) 1985-01-03
JPS60137141A (ja) 1985-07-20
EP0131732B1 (en) 1990-09-05
US4758836A (en) 1988-07-19
CA1246178A (en) 1988-12-06
JPH0640631B2 (ja) 1994-05-25

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