Electronic analog division means

Claim 2

Means for dividing a first signal into a second signal including a balanced bridge circuit, said bridge circuit including at least two bridge legs each including a variable impedance element, first bridge input means to which the first signal is fed, said first bridge input means being connected in one of said bridge legs and including means to effect a change in the impedance of the one of said variable impedance elements in response to changes in the first signal to unbalance said bridge circuit, voltage divider means including the variable impedance elements in said two bridge legs, other means connected to said bridge circuit and to said variable impedance elements to respond to any unbalance in the bridge circuit due to changes in the first signal, said last-named means including means to rebalance the bridge by varying the impedance of the other of said variable impedance elements, and second bridge input means including means connected to apply a second signal across a portiOn of said voltage divider means including said variable impedance elements, an output signal being produced across a portion of said voltage divider means which varies in direct proportion to the second signal and inversely in proportion to the first signal.

Claim 3

The means defined in claim 1 wherein said first input means include control means and photoconductor means, said photoconductor means being connected in the said one leg of the bridge circuit, a portion of said first signal being applied across said photoconductor means, said control means including means to detect variations in the potential across said photoconductor means, and said control means including means to vary the conductance of the photoconductor means in response to detected potential variations in a direction to maintain the potential across the photoconductor means relatively constant.

Claim 4

The means defined in claim 1 wherein each of said variable impedance elements includes a photoconductor having a light source associated therewith, the intensity of the light from the light source associated with the said one variable impedance element varying with the magnitude of the first signal to control the conductance of said photoconductor, said means responsive to the unbalanced condition of the bridge circuit including a DC amplifier whose output is connected in a circuit with the light source associated with the photoconductor in the other variable impedance element to vary the potential applied thereto in a direction to maintain the bridge circuit in a balanced condition.

Claim 5

Means for dividing a first signal into a second signal including a multileg bridge circuit and first bridge input means to which the first signal is fed, first variable impedance means connected to said first input means in one leg of said bridge circuit, said first variable impedance means including means to vary the impedance thereof in inverse proportion to variations of said first signal, means included in the bridge circuit connected across said first variable impedance means for responding to variations in the impedance thereof to produce control outputs which vary in inverse relationship to said variations in the impedance of said first variable impedance means, second variable impedance means operatively connected to said impedance-responsive means and controlled by the control outputs thereof, the impedance of said second variable impedance means varying in direct proportion to the variations in impedance of said first variable impedance means, and second input means to which said second signal is fed connected to said second variable impedance means including means to apply a portion of said second signal across said second variable impedance means, the magnitude of the proportion of said second signal appearing across said second variable impedance means depending on the impedance thereof, the portion of the second signal appearing across said second variable impedance means being a function of the ratio of the first and second signals.

Claim 6

Means for dividing a first signal into a second signal including a multileg bridge circuit and first bridge input means to which the first signal is fed, first variable impedance means connected to said first input means in one leg of said bridge circuit, said first variable impedance means including means to vary the impedance thereof in inverse proportion to variations of said first signal, means included in the bridge circuit connected across said first variable impedance means for responding to variations in the impedance thereof to produce control outputs which vary in inverse relationship to said variations in the impedance of said first variable impedance means, second variable impedance means operatively connected to said impedance-responsive means and controlled by the control outputs thereof, the impedance of said second variable impedance means varying in direct proportion to the variations in impedance of said first variable impedance means, and second input means to which said second signal is fed connected to said second variable impedance means including means to apply a portion of said second signal across said second variable impedance means, the magnitude of the proportion of said second signal appearing across said second variable impedance means depending on the impedance thereof, the portion of the second signal appearing across said second variable impedance means being a function of the ratio of the first and second signals.

Claim 7

Electronic means for producing a division operation between two analog input signals represented as input signals Ea and Eb comprising a Wheatstone bridge circuit having two pairs of opposed bridge legs and two pairs of opposed bridge corners therebetween, means including a source of DC energy connected across one pair of opposed bridge corners and means including DC amplifier means connected across said other pair of opposed bridge corners, said DC amplifier means responding to imbalance in the condition of the bridge circuit, a first variable impedance device connected in one of the bridge legs, said variable impedance device including an impedance portion and an impedance control portion, a first bridge input circuit for applying to the bridge circuit the input signal Eb connected to the bridge circuit such that a portion of the input signal Eb is across the impedance portion of the first variable impedance device, means responsive to changes in the voltage across the first variable impedance device due to changes in the input signal Eb, said voltage responsive means being connected to the impedance control portion of the first variable impedance for varying the impedance of the impedance portion of the first variable impedance device in a direction to maintain the voltage thereacross relatively constant, changes in the impedance of said first variable impedance device producing an imbalance in the bridge circuit which is detected by the DC amplifier means, a second variable impedance device connected in another one of the legs of the bridge circuit, said second variable impedance device having an impedance portion and an impedance control portion, the impedance control portion of said second variable impedance device being operatively connected to the DC amplifier means whereby imbalance of the bridge sensed by the DC amplifier means operate to control the impedance of said second variable impedance device to change the impedance thereof in a direction to restore and maintain the bridge in a balanced condition, and second input means connected to the bridge circuit such that a portion of the input signal Ea is applied across the impedance portion of said second variable impedance device, the signal appearing across the impedance portion of said second variable impedance device being a function of the ratio of the input signals Ea and Eb.

Claim 8

Electronic means for producing a division operation between two analog input signals represented as input signals Ea and Eb comprising a Wheatstone bridge circuit having two pairs of opposed bridge legs and two pairs of opposed bridge corners therebetween, means including a source of DC energy connected across one pair of opposed bridge corners and means including DC amplifier means connected across said other pair of opposed bridge corners, said DC amplifier means responding to imbalance in the condition of the bridge circuit, a first variable impedance device connected in one of the bridge legs, said variable impedance device including an impedance portion and an impedance control portion, a first bridge input circuit for applying to the bridge circuit the input signal Eb connected to the bridge circuit such that a portion of the input signal Eb is across the impedance portion of the first variable impedance device, means responsive to changes in the voltage across the first variable impedance device due to changes in the input signal Eb, said voltage responsive means being connected to the impedance control portion of the first variable impedance for varying the impedance of the impedance portion of the first variable impedance device in a direction to maintain the voltage thereacross relatively constant, changes in the impedance of said first variable impedance device producing an imbalance in the bridge circuit which is detected by the DC amplifier means, a second variable impedance device connected in another one of the legs of the bridge circuit, said second variable impedance device having an impedance portion and an impedance control portion, the impedance control portion of said second variable impedance device being operatively connected to the DC amplifier means whereby imbalance of the bridge sensed by the DC amplifier means operate to control the impedance of said second variable impedance device to change the impedance thereof in a direction to restore and maintain the bridge in a balanced condition, and second input means connected to the bridge circuit such that a portion of the input signal Ea is applied across the impedance portion of said second variable impedance device, the signal appearing across the impedance portion of said second variable impedance device being a function of the ratio of the input signals Ea and Eb.

Claim 9

The electronic means defined in claim 5 including a plurality of similar bridge circuits all of which have one leg in common, said common leg including the impedance portion of said first variable impedance device, each of said bridge circuits having another leg that includes an impedance portion of a second variable impedance device, each of said second variable impedance devices being capable of being connected to a different input signal.

Claim 10

A circuit for generating an output signal which can be expressed as a function of Ea/Eb where Ea and Eb are analog input signals fed to the circuit, said circuit including power supply means, a balanced bridge circuit having first and second impedance legs connected in series across said power supply means, and third and fourth impedance legs connected in series across said power supply, said third leg including first variable impedance means, and said fourth leg including second variable impedance means, first input means connected to said first variable impedance means including means for applying a portion of the input signal Eb thereacross, said first input means including first control means responsive to variations in the input signal Eb and including means for varying the impedance of said first variable impedance means in an inverse relationship to the variations of the input signal Eb so as to maintain the level of the input signal Eb applied to the first variable impedance means relatively constant, said variations in the impedance of said first variable impedance means causing an unbalanced impedance condition of said bridge circuit, second control means operatively connected to said second variable impedance means to control the impedance thereof, said second control means including means responsive to unbalanced conditions that occur in said bridge circuit, said second control means including means for varying the impedance of said second variable impedance means due to imbalances in the bridge circuit in a direction to restore and maintain the bridge in a balanced condition, second bridge input means connected to the second variable impedance means including means for applying a portion of the input signal Ea thereacross, and output means connected across said second variable impedance means, an output signal being produced in the output means as a result of the bridge being maintained in a balanced condition, which output signal is a function of the ratio Ea/Eb of the input signals.

Claim 11

A circuit for generating an output signal which can be expressed as a function of Ea/Eb where Ea and Eb are analog input signals fed to the circuit, said circuit including power supply means, a balanced bridge circuit having first and second impedance legs connected in series across said power supply means, and third and fourth impedance legs connected in series across said power supply, said third leg including first variable impedance means, and said fourth leg including second variable impedance means, first input means connected to said first variable impedance means including means for applying a portion of the input signal Eb thereacross, said first input means including first control means responsive to variations in the input signal Eb and including means for varying the impedance of said first variable impedance means in an inverse relationship to the variations of the input signal Eb so as to maintain the level of the input signal Eb applied to the first variable impedance means relatively constant, said variations in the impedance of said first variable impedance means causing an unbalanced impedance condition of said bridge circuit, second control means operatively connected to said second variable impedance means to control the impedance thereof, said second control means including means responsive to unbalanced conditions that occur in said bridge circuit, said second control means including means for varying the impedance of said second variable impedance means due to imbalances in the bridge circuit in a direction to restore and maintain the bridge in a balanced condition, second bridge input means connected to the second variable impedance means including means for applying a portion of the input signal Ea thereacross, and output means connected across said second variable impedance means, an output signal being produced in the output means as a result of the bridge being maintained in a balanced condition, which output signal is a function of the ratio Ea/Eb of the input signals.

Claim 12

The circuit defined in claim 7 wherein said first and second variable impedance means are photoconductor devices each including an associated light source and light-responsive means, the impedance of said first and second variable impedance devices varying in an inverse relationship with the intensity of light produced by the associated light sources.

Claim 13

The circuit defined in claim 7 wherein said means responsive to unbalanced conditions that occur in said bridge circuit include direct-current amplifier means.

Claim 14

The circuit defined in claim 7 including means to prevent the input signals Ea and Eb from affecting said first and second bridge legs.

Claim 15

The circuit defined in claim 7 including means to prevent the input signals Ea and Eb from affecting the power supply.

Claim 16

The circuit defined in claim 7 wherein said first input means include an input terminal to which the input signal Eb is applied and an impedance member connected between said input terminal and said first variable impedance means.

Claim 17

The circuit defined in claim 7 wherein said first control means produces a direct-current output signal which varies with the variations in signal level detected across the first impedance means.

Claim 18

Means for generating signals which are functions of the ratios Ea/Eb and Ec/Eb of input signals Ea, Eb, and Ec including first and second balanced bridge circuits both of which have at least one bridge leg in common, divisor input means associated with the common bridge leg to which the input signal Eb is fed, said divisor input means including means in said common leg to unbalance said first and second bridge circuits in response to variations of the input signal Eb by producing changes in the impedance of the means in said common leg in an inverse relationship to changes of the input signal Eb, first variable impedance means connected in another leg of said first bridge circuit, second variable impedance means connected in another leg of said second bridge circuit, means connected to respond to unbalanced conditions produced in said first bridge circuit as a result of changes in the impedance of the common bridge leg, said last-named means including means to restore said first bridge circuit to a balanced condition by varying the impedance of said first variable impedance means, means connected to respond to unbalanced conditions produced in said second bridge circuit as a result of changes in the impedance of the common bridge leg, said last-named means including means to restore said second bridge circuit to a balanced condition by varying the impedance of said second variable impedance means, a first impedance member connected in series with said first variable impedance means, a second impedance member connected in series with said second variable impedance means, means for applying the input signal Ea across the series combination of said first impedance member and said first variable impedance means, means for applying said input signal Ec across the series combination of said second impedance member and said second variable impedance means, a first output signal which is a function of the ratio Ea/Eb of the input signals Ea and Eb being present across said first variable impedance means and a second output signal which is a function of the ratio Ec/Eb of the input signals Ec and Eb being present across said second variable impedance means.

Claim 19

Means for generating signals which are functions of the ratios Ea/Eb and Ec/Eb of input signals Ea, Eb, and Ec including first and second balanced bridge circuits both of which have at least one bridge leg in common, divisor input means associated with the common bridge leg to which the input signal Eb is fed, said divisor input means including means in said common leg to unbalance said first and second bridge circuits in response to variations of the input signal Eb by producing changes in the impedance of the means in said common leg in an inverse relationship to changes of the input signal Eb, first variable impedance means connected in another leg of said first bridge circuit, second variable impedance means connected in another leg of said second bridge circuit, means connected to respond to unbalanced conditions produced in said first bridge circuit as a result of changes in the impedance of the common bridge leg, said last-named means including means to restore said first bridge circuit to a balanced condition by varying the impedance of said first variable impedance means, means connected to respond to unbalanced conditions produced in said second bridge circuit as a result of changes in the impedance of the common bridge leg, said last-named means including means to restore said second bridge circuit to a balanced condition by varying the impedance of said second variable impedance means, a first impedance member connected in series with said first variable impedance means, a second impedance member connected in series with said second variable impedance means, means for applying the input signal Ea across the series combination of said first impedance member and said first variable impedance means, means for applying said input signal Ec across the series combination of said second impedance member and said second variable impedance means, a first output signal which is a function of the ratio Ea/Eb of the input signals Ea and Eb being present across said first variable impedance means and a second output signal which is a function of the ratio Ec/Eb of the input signals Ec and Eb being present across said second variable impedance means.

Claim 20

Means for dividing a plurality of dividend input signals by a divisor input signal to produce a plurality of quotient output signals representing the ratio of each dividend input signal by the divisor input signal including a plurality of balanced bridge circuits all of which have one bridge leg in common, divisor input means connected in saId common leg, means to vary the impedance of said common leg to unbalance the impedance characteristics of all of said plurality of bridge circuits simultaneously, said impedance varying means including means responsive to variations of the divisor input signal, a plurality of variable impedances each being connected respectively into another leg of each of said plurality of bridge circuits, means connected to each of said bridge circuits to respond to any unbalance of the associated bridge circuit, said last-named means including means for varying the impedances of said associated variable impedances to restore a balanced condition to each of said bridge circuits, a voltage divider circuit associated with each of said bridge circuits and formed in part by the associated variable impedance of said circuit dividend input means associated with each bridge circuit including means for applying an associated dividend input signal across each of the associated voltage divider circuits, a quotient output signal being produced across a portion of each respective voltage divider circuit, said quotient output signals in each of said bridge circuits being directly proportional to the associated dividend input signal and inversely proportional to the divisor input signal.

Claim 21

Means for dividing a plurality of dividend input signals by a divisor input signal to produce a plurality of quotient output signals representing the ratio of each dividend input signal by the divisor input signal including a plurality of balanced bridge circuits all of which have one bridge leg in common, divisor input means connected in saId common leg, means to vary the impedance of said common leg to unbalance the impedance characteristics of all of said plurality of bridge circuits simultaneously, said impedance varying means including means responsive to variations of the divisor input signal, a plurality of variable impedances each being connected respectively into another leg of each of said plurality of bridge circuits, means connected to each of said bridge circuits to respond to any unbalance of the associated bridge circuit, said last-named means including means for varying the impedances of said associated variable impedances to restore a balanced condition to each of said bridge circuits, a voltage divider circuit associated with each of said bridge circuits and formed in part by the associated variable impedance of said circuit dividend input means associated with each bridge circuit including means for applying an associated dividend input signal across each of the associated voltage divider circuits, a quotient output signal being produced across a portion of each respective voltage divider circuit, said quotient output signals in each of said bridge circuits being directly proportional to the associated dividend input signal and inversely proportional to the divisor input signal.

Claim 22

The means defined in claim 15 wherein said divisor input means include variable conductance means connected in said common bridge leg and control means associated with said variable conductance means, a portion of said divisor input signal being across said variable conductance means, said control means responding to variations in the portion of the divisor input signal across said variable conductance means and including means for varying the conductance of said variable conductance in a direction and in proportion to variations of the divisor input signal so as to maintain the potential across the variable conductance relatively constant.

Claim 23

Means for dividing a first signal into a second signal including a balanced bridge circuit, said bridge circuit including at least two bridge legs, first bridge input means to which the first signal is fed, said first bridge input means being connected in one of said bridge legs to unbalance said bridge circuit in response to changes in the first signal, voltage divider means including variable impedance means being connected in another of said legs of said bridge circuit, means connected to said bridge circuit and to said variable impedance means responsive to any unbalance in the bridge circuit due to changes in the first signal, said last-named means including means to rebalance the bridge by varying the impedance of said variable impedance means, said first input means including control means and photoconductor means, said photoconductor means being connected in said one leg of the bridge circuit, a portion of said first signal being applied across said photoconductor means, said control means including means to detect variations in the potential across said photoconductor means, said control means including means to vary the conductance of the photoconductor means in response to the detected variations in a direction to maintain the potential across the photoconductor means relatively constant, said first signal including an AC component, and said control means including means connected to said photoconductor means to detect AC signals appearing thereacross and to generate therefrom variable DC signals, and a light source associated with said photoconductor means to which the variable DC signals are applied, the intensity of the light produced by said light source controlling the conductance of the photoconductor means, and second bridge input means connected to apply the second signal across said voltage divider means including said variable impedance means, an output signal being produced across a portion of said voltage divider means which is directly proportional to the second signal and inversely proportional to the first signal.

Claim 24

Means for dividing a first signal into a second signal including a balanced bridge circuit, said bridge circuit including at least two bridge legs, first bridge input means to which the first signal is fed, said first bridge input means being connected in one of said bridge legs to unbalance said bridge circuit in response to changes in the first signal, voltage divider means including variable impedance means being connected in another of said legs of said bridge circuit, means connected to said bridge circuit and to said variable impedance means responsive to any unbalance in the bridge circuit due to changes in the first signal, said last-named means including means to rebalance the bridge by varying the impedance of said variable impedance means, said first input means including control means and photoconductor means, said photoconductor means being connected in said one leg of the bridge circuit, a portion of said first signal being applied across said photoconductor means, said control means including means to detect variations in the potential across said photoconductor means, said control means including means to vary the conductance of the photoconductor means in response to the detected variations in a direction to maintain the potential across the photoconductor means relatively constant, said first signal including an AC component, and said control means including means connected to said photoconductor means to detect AC signals appearing thereacross and to generate therefrom variable DC signals, and a light source associated with said photoconductor means to which the variable DC signals are applied, the intensity of the light produced by said light source controlling the conductance of the photoconductor means, and second bridge input means connected to apply the second signal across said voltage divider means including said variable impedance means, an output signal being produced across a portion of said voltage divider means which is directly proportional to the second signal and inversely proportional to the first signal.

Claim 25

A circuit for generating an output signal which can be expressed as a function of Ea/Eb where Ea and Eb are analog input signals fed to the circuit, said circuit including power supply means, a balanced bridge circuit having first and second impedance legs connected in series across said power supply means, and third and fourth impedance legs connected in series across said power supply, said third leg including first variable impedance means, and said fourth leg including second variable impedance means, first input means connected to said first variable impedance means including means for applying the input signal Eb thereto, said first input means including first control means responsive to variations in the input signal Eb and including means for varying the impedance of said first variable impedance means in inverse relationship to the variations of the input signal Eb so as to maintain the level of the input signal Eb applied to the first variable impedance means relatively constant, said variations in the impedance of said first variable impedance means causing an unbalanced condition of said bridge circuit, second control means operatively connected to said second variable impedance means to control the impedance thereof, said second control means including means responsive to unbalanced conditions that occur in said bridge circuit, said second control means including means for varying the impedance of said second variable impedance means in a direction to restore and maintain the bridge in a balanced condition, second bridge input means connected to the second variable impedance means including means for applying the input signal Ea thereto, and output means connected across said second variable impedance means, an output signal being produced in the output means as a result of the bridge being maintained in a balanced condition which is a function of the ratio Ea/Eb of the input signals, said first control means producing a direct current output signal which varies with the variations in signal level detected across the first impedance means, said first control means also including a charge storage device and an amplifier having relatively high input impedance characteristics

Claim 26

A circuit for generating an output signal which can be expressed as a function of Ea/Eb where Ea and Eb are analog input signals fed to the circuit, said circuit including power supply means, a balanced bridge circuit having first and second impedance legs connected in series across said power supply means, and third and fourth impedance legs connected in series across said power supply, said third leg including first variable impedance means, and said fourth leg including second variable impedance means, first input means connected to said first variable impedance means including means for applying the input signal Eb thereto, said first input means including first control means responsive to variations in the input signal Eb and including means for varying the impedance of said first variable impedance means in inverse relationship to the variations of the input signal Eb so as to maintain the level of the input signal Eb applied to the first variable impedance means relatively constant, said variations in the impedance of said first variable impedance means causing an unbalanced condition of said bridge circuit, second control means operatively connected to said second variable impedance means to control the impedance thereof, said second control means including means responsive to unbalanced conditions that occur in said bridge circuit, said second control means including means for varying the impedance of said second variable impedance means in a direction to restore and maintain the bridge in a balanced condition, second bridge input means connected to the second variable impedance means including means for applying the input signal Ea thereto, and output means connected across said second variable impedance means, an output signal being produced in the output means as a result of the bridge being maintained in a balanced condition which is a function of the ratio Ea/Eb of the input signals, said first control means producing a direct current output signal which varies with the variations in signal level detected across the first impedance means, said first control means also including a charge storage device and an amplifier having relatively high input impedance characteristics

Claim 27

The circuit defined in claim 18 wherein the same means that produce a direct current signal include means connected to said high input impedance amplifier to rectify and filter outputs therefrom, a direct current amplifier connected to amplify the rectified and filtered outputs, and a light source connected to the output of the direct current amplifier, the intensity of the light produced by said light source varying with the output of the direct current amplifier and controlling the impedance of said first variable impedance means.