Capacitive tank gaging apparatus being independent of liquid distribution

Claim 2

Tank gaging apparatus comprising A. a liquid-containing structure having 1. longitudinal and transverse directions 2. a longitudinally extending inner surface defining the transverse boundaries of said structure, and 3. a nonrectangular cross section, B. first and second groups of electrodes, 1. said electrodes extending longitudinally along said surface, 2. said electrodes being spaced apart around said surface, and 3. said groups being opposite each other for generating a uniform electric field. C. a source of time-varying voltage, D. means interconnecting said source and electrodes for applying electrical potentials to the respective electrodes, the electrical potential applied to each electrode being substantially equal to the potential at the location of that electrode in a first uniform field extending from said first group to said second group, and E. output means responsive to the current from said source to said electrode groups.

Claim 3

a longitudinally extending inner surface defining the transverse boundaries of said structure, and

Claim 4

a longitudinally extending inner surface defining the transverse boundaries of said structure, and

Claim 5

said electrodes being spaced apart around said surface, and

Claim 6

said electrodes being spaced apart around said surface, and

Claim 7

Apparatus according to claim 1 wherein A. further electrodes are arranged in third and fourth groups opposite each other for generating a uniform electric field along a second direction transverse to a first direction between said first and second groups, B. said interconnecting means additionally including means for applying electrical potentials to the respective electrodes in said third and fourth groups, the electrical potential applied to each electrode being substantially equal to the potential developed at the location of that electrode in a second uniform electric field extending between said third and fourth groups, and C. further comprising means for producing an output signal corresponding to the currents from said source for generating said first electric field and said second electric field.

Claim 8

a longitudinally extending inner surface defining the transverse boundaries of said structure B. first and second groups of electrodes

Claim 9

a longitudinally extending inner surface defining the transverse boundaries of said structure B. first and second groups of electrodes

Claim 10

said electrodes being spaced part around said surface

Claim 11

said electrodes being spaced part around said surface

Claim 12

said third and fourth groups.

Claim 13

said third and fourth groups.

Claim 14

a longitudinally extending inner surface defining the transverse boundaries of said structure, B. first and second groups of electrodes,

Claim 15

a longitudinally extending inner surface defining the transverse boundaries of said structure, B. first and second groups of electrodes,

Claim 16

said electrodes being spaced apart around said surface

Claim 17

said electrodes being spaced apart around said surface

Claim 18

connected to said primary means so that in said first condition it connects said transformer means to normally energize said electrodes to provide said potentials at said electrodes, and

Claim 19

connected to said primary means so that in said first condition it connects said transformer means to normally energize said electrodes to provide said potentials at said electrodes, and

Claim 20

spaced apart circumferentially around said surface and insulated from each other,

Claim 21

spaced apart circumferentially around said surface and insulated from each other,

Claim 22

distributed substantially throughout said surface, B. source means connected with said electrodes for applying time-varying voltages to each electrode, each voltage from said source means being measurable with reference to a ground potential,

Claim 23

distributed substantially throughout said surface, B. source means connected with said electrodes for applying time-varying voltages to each electrode, each voltage from said source means being measurable with reference to a ground potential,

Claim 24

in said second condition said transformer means energize both of said electrode groups with the same potential so that current to said electrodes corresponds to the stray capacitance of said electrodes, F. means sensing the current applied to said transformer means means in each condition of said switching means, G. a reference capacitor connected to said primary means to provide a reference current when said switching means is in said first condition corresponding in magnitude to, and having the opposite phase from, the current produced in said sensing means when said volume is empty of liquid, and H. means coupled to said transformer means and said switching means for producing a signal corresponding to the difference between the currents in said sensing means when said switching means is alternated between said first and second conditions.

Claim 25

in said second condition said transformer means energize both of said electrode groups with the same potential so that current to said electrodes corresponds to the stray capacitance of said electrodes, F. means sensing the current applied to said transformer means means in each condition of said switching means, G. a reference capacitor connected to said primary means to provide a reference current when said switching means is in said first condition corresponding in magnitude to, and having the opposite phase from, the current produced in said sensing means when said volume is empty of liquid, and H. means coupled to said transformer means and said switching means for producing a signal corresponding to the difference between the currents in said sensing means when said switching means is alternated between said first and second conditions.

Claim 26

said groups being opposite each other for generating a uniform electric field C. a source of time-varying voltage D. transformer means connected between said source and said electrodes, said transformer means having primary means and multiple-tapped secondary means for applying electrical potentials to the respective electrodes, the electrical potential applied to each electrode being substantially equal to the potential at the location of that electrode in a uniform field extending from said first group to said second group, E. switching means

Claim 27

said groups being opposite each other for generating a uniform electric field C. a source of time-varying voltage D. transformer means connected between said source and said electrodes, said transformer means having primary means and multiple-tapped secondary means for applying electrical potentials to the respective electrodes, the electrical potential applied to each electrode being substantially equal to the potential at the location of that electrode in a uniform field extending from said first group to said second group, E. switching means

Claim 28

said groups being opposite each other for generating a uniform electric field C. a source of time-varying voltage, D. means interconnecting said source and said electrodes for applying electrical potentials to the respective electrodes, the electrical potential applied to each electrode being substantially equal to the potential at the location of that electrode in a uniform field extending from said first group to said second group, E. further electrodes being arranged in third and fourth groups along a second direction transverse to said first direction for generating a second uniform electric field F. said interconnecting means further iNcluding means for applying electrical potentials to the respective electrodes in said third and fourth groups, the electrical potential applied to each electrode being substantially equal to the potential at the location of that electrode by a second uniform electric field transverse to said first field and extending between said third and fourth groups of electrodes, and G. means for producing a signal proportional to the average of the currents from said source to said

Claim 29

said groups being opposite each other for generating a uniform electric field C. a source of time-varying voltage, D. means interconnecting said source and said electrodes for applying electrical potentials to the respective electrodes, the electrical potential applied to each electrode being substantially equal to the potential at the location of that electrode in a uniform field extending from said first group to said second group, E. further electrodes being arranged in third and fourth groups along a second direction transverse to said first direction for generating a second uniform electric field F. said interconnecting means further iNcluding means for applying electrical potentials to the respective electrodes in said third and fourth groups, the electrical potential applied to each electrode being substantially equal to the potential at the location of that electrode by a second uniform electric field transverse to said first field and extending between said third and fourth groups of electrodes, and G. means for producing a signal proportional to the average of the currents from said source to said

Claim 30

Apparatus according to claim 1 wherein said output means additionally includes means for subtracting from said current a current substantially equal to the current to said electrodes when said tank is empty of liquid.

Claim 31

said groups being opposite each other for generating a uniform electric field. C. a source of time-varying voltage, D. means interconnecting said source and electrodes for applying electrical potentials to the respective electrodes, the electrical potential applied to each electrode being substantially equal to the potential at the location of that electrode in a first uniform field extending from said first group to said second group, and E. output means responsive to the current from said source to said electrode groups.

Claim 32

said groups being opposite each other for generating a uniform electric field. C. a source of time-varying voltage, D. means interconnecting said source and electrodes for applying electrical potentials to the respective electrodes, the electrical potential applied to each electrode being substantially equal to the potential at the location of that electrode in a first uniform field extending from said first group to said second group, and E. output means responsive to the current from said source to said electrode groups.

Claim 33

a nonrectangular cross section, B. first and second groups of electrodes,

Claim 34

a nonrectangular cross section, B. first and second groups of electrodes,

Claim 35

Tank gaging apparatus comprising A. a liquid-containing structure having

Claim 36

Tank gaging apparatus comprising A. a liquid-containing structure having

Claim 37

Tank gaging apparatus comprising A. a liquid-containing structure having

Claim 38

Tank gaging apparatus comprising A. a liquid-containing structure having

Claim 39

Apparatus according to claim 5 wherein said switching means includes means for generating a voltage changing in amplitude between first and second values in synchronism with the operation of said switching means between said first and second conditions and said difference signal producing means comprises A. a first phase detector coupled to said sensing means and said source for receiving a voltage corresponding to sensed currents and a voltage corresponding to the source voltage applied to said transformer means, and B. a second phase detector coupled to said first phase detector and said switching means for receiving a voltage corresponding to the voltage output from said first phase detector and the voltage from said switching means.

Claim 40

Apparatus for measuring the quantity of a liquid, said apparatus comprising A. a cylindrical tank having a cylindrical wall and closed on at least one end by an outwardly extending bulbous closure, B. longitudinally extending electrodes mounted along the inner surface of said cylindrical wall, C. electrodes mounted on the inner surface of said end closure, D. an electrical source, E. means interconnecting said source and said electrodes for applying electrical potentials to The respective electrodes, the electrical potential applied to each electrode being substantially equal to the potential at the location of that electrode in a uniform electric field passing through said tank from one side to the other, and F. output means responsive to the combined currents to said electrodes.

Claim 41

Apparatus for measuring the quantity of a liquid, said apparatus comprising A. a cylindrical tank having a cylindrical wall and closed on at least one end by an outwardly extending bulbous closure, B. longitudinally extending electrodes mounted along the inner surface of said cylindrical wall, C. electrodes mounted on the inner surface of said end closure, D. an electrical source, E. means interconnecting said source and said electrodes for applying electrical potentials to The respective electrodes, the electrical potential applied to each electrode being substantially equal to the potential at the location of that electrode in a uniform electric field passing through said tank from one side to the other, and F. output means responsive to the combined currents to said electrodes.

Claim 42

Apparatus as defined in claim 7 in which said interconnecting means A. applies electrical potentials of opposite polarities to the respective electrodes on opposite sides of a diameter of said tank, B. the magnitude magnitude of each of said potentials being substantially proportional to the cosine of the angle between a first radius perpendicular to said diameter and a second radius extending from the axis of said tank to said electrode.

Claim 43

Apparatus for measuring the mass of liquid in a container of known volume, said container being substantially cylindrical and having a first diameter, a second diameter perpendicular to said first diameter and having a height dimension on the axial direction of the container, said apparatus comprising A. a plurality of electrodes

Claim 44

Apparatus for measuring the mass of liquid in a container of known volume, said container being substantially cylindrical and having a first diameter, a second diameter perpendicular to said first diameter and having a height dimension on the axial direction of the container, said apparatus comprising A. a plurality of electrodes