Capacitive proximity sensor

Kronberg, James W

Title: Capacitive proximity sensor

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Abstract

A proximity sensor based on a closed field circuit. The circuit comprises a ring oscillator using a symmetrical array of plates that creates an oscillating displacement current. The displacement current varies as a function of the proximity of objects to the plate array. Preferably the plates are in the form of a group of three pair of symmetric plates having a common center, arranged in a hexagonal pattern with opposing plates linked as a pair. The sensor produces logic level pulses suitable for interfacing with a computer or process controller. The proximity sensor can be incorporated into a load cell, a differential pressure gauge, or a device for measuring the consistency of a characteristic of a material where a variation in the consistency causes the dielectric constant of the material to change.

Inventors:

Kronberg, James W ^[1]

Aiken, SC

Issue Date:: 1994-01-01

Research Org.:: Savannah River Site (SRS), Aiken, SC (United States)

OSTI Identifier:: 869327

Patent Number(s):: 5315884

Assignee:: United States of America as represented by United States (Washington, DC)

Patent Classifications (CPCs):: G - PHYSICS G01 - MEASURING G01L - MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE

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G - PHYSICS G01 - MEASURING G01L - MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
G01L3/106 - {involving electrostatic means}

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DOE Contract Number:: AC09-89SR18035

Resource Type:: Patent

Country of Publication:: United States

Language:: English

Subject:: capacitive; proximity; sensor; based; closed; field; circuit; comprises; oscillator; symmetrical; array; plates; creates; oscillating; displacement; current; varies; function; plate; preferably; form; pair; symmetric; common; center; arranged; hexagonal; pattern; opposing; linked; produces; logic; level; pulses; suitable; interfacing; computer; process; controller; incorporated; load; cell; differential; pressure; gauge; device; measuring; consistency; characteristic; material; variation; causes; dielectric; constant; change; proximity sensor; displacement current; load cell; dielectric constant; process control; differential pressure; pressure gauge; process controller; sensor based; symmetrical array; pulses suitable; circuit comprises; closed field; field circuit; common center; current varies; /73/324/

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                    Kronberg, James W. Capacitive proximity sensor.  United States: N. p., 1994. 
        Web.

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                    Kronberg, James W. Capacitive proximity sensor.  United States.

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                    Kronberg, James W. Sat .  
        "Capacitive proximity sensor".  United States.  https://www.osti.gov/servlets/purl/869327.

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@article{osti_869327,

  title        = {Capacitive proximity sensor},

  author       = {Kronberg, James W},

  abstractNote = {A proximity sensor based on a closed field circuit. The circuit comprises a ring oscillator using a symmetrical array of plates that creates an oscillating displacement current. The displacement current varies as a function of the proximity of objects to the plate array. Preferably the plates are in the form of a group of three pair of symmetric plates having a common center, arranged in a hexagonal pattern with opposing plates linked as a pair. The sensor produces logic level pulses suitable for interfacing with a computer or process controller. The proximity sensor can be incorporated into a load cell, a differential pressure gauge, or a device for measuring the consistency of a characteristic of a material where a variation in the consistency causes the dielectric constant of the material to change.},

  doi          = {},

  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {1994},

  month        = {1}

}

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