Apparatus and methods for measuring and detecting variations in the value of a capacitor

Claim 1

A method for measuring the value of a capacitor comprising: (a) providing a capacitor to be measured having a value of capacitance, C; (b) electrically connecting said capacitor to a detector circuit, said detector circuit including a known load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said time interval T; (c) applying said voltage input, V, to said detector circuit and measuring the sample voltage, v, across the circuit element after said time interval T; and (d) thereafter, computing the value of said capacitor from the value of a single sample v, from said elapsed time interval T, from said known load impedance R, and from said known wave form of the input voltage V.

Claim 2

A method for measuring the value of a capacitor comprising: (a) providing a capacitor to be measured having a value of capacitance, C; (b) electrically connecting said capacitor to a detector circuit, said detector circuit including a known load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said time interval T; (c) applying said voltage input, V, to said detector circuit and measuring the sample voltage, v, across the circuit element after said time interval T; and (d) thereafter, computing the value of said capacitor from the value of a single sample v, from said elapsed time interval T, from said known load impedance R, and from said known wave form of the input voltage V.

Claim 7

A method for measuring variations in the value of a capacitor comprising: (a) providing a capacitor to be measured having a generally predetermined value of capacitance, C; (b) electrically connecting said capacitor to a detector circuit, said detector circuit including a known load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said time interval T; (c) applying said voltage input, V, to said detector circuit and measuring the sample voltage, v, across the circuit element after said time interval T; (d) thereafter, computing the value of said capacitor from the value of a single sample v, from said elapsed time interval T, from said known load impedance R, and from said known wave form of the input voltage V; and (e) repeating steps (c)-(d) at various times to measure variations in value of the capacitor, if any, with respect to time.

Claim 8

A method for measuring variations in the value of a capacitor comprising: (a) providing a capacitor to be measured having a generally predetermined value of capacitance, C; (b) electrically connecting said capacitor to a detector circuit, said detector circuit including a known load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said time interval T; (c) applying said voltage input, V, to said detector circuit and measuring the sample voltage, v, across the circuit element after said time interval T; (d) thereafter, computing the value of said capacitor from the value of a single sample v, from said elapsed time interval T, from said known load impedance R, and from said known wave form of the input voltage V; and (e) repeating steps (c)-(d) at various times to measure variations in value of the capacitor, if any, with respect to time.

Claim 10

A method for detecting variations in the value of a capacitor comprising: (a) providing a capacitor to be measured having a generally predetermined value of capacitance, C; (b) electrically connecting said capacitor to a detector circuit, said detector circuit including a substantially constant load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said elapsed time interval T; (c) applying said voltage input, V, to said detector circuit and measuring the sample voltage, v, across the circuit element after said elapsed time interval T; and (d) detecting variations in the value of said capacitor, in excess of an assigned variation amount, from the sample v, from said elapsed time interval T, and from said known wave form of the input voltage V.

Claim 11

A method for detecting variations in the value of a capacitor comprising: (a) providing a capacitor to be measured having a generally predetermined value of capacitance, C; (b) electrically connecting said capacitor to a detector circuit, said detector circuit including a substantially constant load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said elapsed time interval T; (c) applying said voltage input, V, to said detector circuit and measuring the sample voltage, v, across the circuit element after said elapsed time interval T; and (d) detecting variations in the value of said capacitor, in excess of an assigned variation amount, from the sample v, from said elapsed time interval T, and from said known wave form of the input voltage V.

Claim 25

A method for detecting variations in value of a plurality of capacitors arranged in an array, said method comprising: (a) providing an array of capacitors to be evaluated, each capacitor in said array having a generally predetermined value of capacitance, C, and having an associated address in said array; (b) electrically connecting each said capacitor to at least one detector circuit, said detector circuit including a substantially constant load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said time interval T; (c) sequentially sampling the value of the capacitor at each address in said array by coupling the capacitor to a said detector circuit, applying the voltage input V in a predetermined sampling order to each capacitor in said array, and measuring the sample voltage, v, after said time interval T; (d) providing a processed numerical resultant for each sampled value of each capacitor in said array, said processed numerical resultant being representative of a measured variable per se or of a relational expression of a combination of variables, wherein said variables are selected from v, V, wave form,T and R; and (e) thereafter storing the processed numerical resultant for each address in said array.

Claim 26

A method for detecting variations in value of a plurality of capacitors arranged in an array, said method comprising: (a) providing an array of capacitors to be evaluated, each capacitor in said array having a generally predetermined value of capacitance, C, and having an associated address in said array; (b) electrically connecting each said capacitor to at least one detector circuit, said detector circuit including a substantially constant load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said time interval T; (c) sequentially sampling the value of the capacitor at each address in said array by coupling the capacitor to a said detector circuit, applying the voltage input V in a predetermined sampling order to each capacitor in said array, and measuring the sample voltage, v, after said time interval T; (d) providing a processed numerical resultant for each sampled value of each capacitor in said array, said processed numerical resultant being representative of a measured variable per se or of a relational expression of a combination of variables, wherein said variables are selected from v, V, wave form,T and R; and (e) thereafter storing the processed numerical resultant for each address in said array.

Claim 42

An apparatus for detecting and measuring small variations in the value of at least one capacitor having a generally predetermined value of capacitance, C, said apparatus comprising: a detector circuit including a substantially constant resistive load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, having substantially a step wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across said load after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said time interval T; means for electrically connecting said capacitor being measured to said detector circuit in series with said load, whereby, upon connecting the capacitor to said detector circuit, applying said step voltage input, V, and measuring the instantaneous voltage, v, after elapsed time interval T, the value of the capacitor, C, may be determined in accordance with the formula: ##EQU11##

Claim 43

An apparatus for detecting and measuring small variations in the value of at least one capacitor having a generally predetermined value of capacitance, C, said apparatus comprising: a detector circuit including a substantially constant resistive load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, having substantially a step wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across said load after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said time interval T; means for electrically connecting said capacitor being measured to said detector circuit in series with said load, whereby, upon connecting the capacitor to said detector circuit, applying said step voltage input, V, and measuring the instantaneous voltage, v, after elapsed time interval T, the value of the capacitor, C, may be determined in accordance with the formula: ##EQU11##

Claim 54

A method for detecting variations in the value of a capacitor in excess of an assigned variation amount and in the presence of electrical noise comprising: (a) providing a capacitor to be measured having a generally predetermined reference value of capacitance, C and assigning a first value for said assigned variation amount; (b) electrically connecting said capacitor to a detector circuit, said detector circuit including a substantially constant load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said elapsed time interval T; (c) applying said voltage input, V, to said detector circuit and measuring the sample voltage, v, across the circuit element after said elapsed time interval T; (d) detecting variations in the value of said capacitor, in excess of an assigned variation amount, from the sample v, from said elapsed time interval T, and from said known wave form of the input voltage V; (e) sampling the analog electrical input signal, v, and storing a processed numerical resultant representative of that sampled value of said analog input signal; (f) comparing the difference between the stored numerical resultant obtained in step (e) and said reference value provided in step (a) with said first assigned variation amount; (g) if the compared values from step (f) for two consecutive sampling steps exceeds the first assigned variation amount thereby identifying that the signal is varying in excess of the assigned variation amount; (h) thereafter, reducing the value of said first assigned variation amount to a smaller second assigned variation amount; (i) continuing said comparing steps until two consecutive comparisons for two consecutive sampling steps are greater than said second assigned variation amount and thereby identifying that said analog signal has returned to its normal reference value; and (j) thereafter, increasing the value of said second assigned variation amount to said first assigned variation amount.

Claim 55

A method for detecting variations in the value of a capacitor in excess of an assigned variation amount and in the presence of electrical noise comprising: (a) providing a capacitor to be measured having a generally predetermined reference value of capacitance, C and assigning a first value for said assigned variation amount; (b) electrically connecting said capacitor to a detector circuit, said detector circuit including a substantially constant load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said elapsed time interval T; (c) applying said voltage input, V, to said detector circuit and measuring the sample voltage, v, across the circuit element after said elapsed time interval T; (d) detecting variations in the value of said capacitor, in excess of an assigned variation amount, from the sample v, from said elapsed time interval T, and from said known wave form of the input voltage V; (e) sampling the analog electrical input signal, v, and storing a processed numerical resultant representative of that sampled value of said analog input signal; (f) comparing the difference between the stored numerical resultant obtained in step (e) and said reference value provided in step (a) with said first assigned variation amount; (g) if the compared values from step (f) for two consecutive sampling steps exceeds the first assigned variation amount thereby identifying that the signal is varying in excess of the assigned variation amount; (h) thereafter, reducing the value of said first assigned variation amount to a smaller second assigned variation amount; (i) continuing said comparing steps until two consecutive comparisons for two consecutive sampling steps are greater than said second assigned variation amount and thereby identifying that said analog signal has returned to its normal reference value; and (j) thereafter, increasing the value of said second assigned variation amount to said first assigned variation amount.

Claim 56

A method for detecting variations in value of a plurality of capacitors arranged in an array in excess of an assigned variation amount and in the presence of electrical noise, said method comprising: (a) providing an array of capacitors to be evaluated, each capacitor in said array having a generally predetermined reference value of capacitance, C, and having an associated address in said array and assigning a first value for said assigned variation amount; (b) electrically connecting each said capacitor to at least one detector circuit, said detector circuit including a substantially constant load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said time interval T; (c) sequentially sampling the value of the capacitor at each address in said array by coupling the capacitor to a said detector circuit, applying the voltage input V in a predetermined sampling order to each capacitor in said array, and measuring the sample voltage, v, after said time interval T; (d) providing a processed numerical resultant for each sampled value of each capacitor in said array, said processed numerical resultant being representative of a measured variable per se or of a relational expression of a combination of variables, wherein said variables are selected from v, V, wave form,T and R; and (e) thereafter storing the processed numerical resultant for each address in said array (f) comparing the difference between the stored numerical resultant obtained in step (e) and the said reference value provided in step (a) with said first assigned variation amount; (g) if the compared values from step (f) for two consecutive sampling steps exceeds the first assigned variation amount thereby identifying that the signal is varying in excess of the assigned variation amount; (h) thereafter, reducing the value of said first assigned variation amount to a smaller second assigned variation amount; (i) continuing said comparing steps until two consecutive comparisons for two consecutive sampling steps are greater than said second assigned variation amount and thereby identifying that said analog signal has returned to its normal reference value; and (j) thereafter, increasing the value of said second assigned variation amount to said first assigned variation amount.

Claim 57

A method for detecting variations in value of a plurality of capacitors arranged in an array in excess of an assigned variation amount and in the presence of electrical noise, said method comprising: (a) providing an array of capacitors to be evaluated, each capacitor in said array having a generally predetermined reference value of capacitance, C, and having an associated address in said array and assigning a first value for said assigned variation amount; (b) electrically connecting each said capacitor to at least one detector circuit, said detector circuit including a substantially constant load impedance, R, connected in series with said capacitor, means for providing a voltage input, V, of known wave form to said detector circuit, means for measuring an instantaneous sample voltage, v, across a circuit element selected from the load impedance or the capacitor being measured after a known time interval T has elapsed, said sampling moment being in a predetermined fixed phase relationship to the input voltage V and means for precisely controlling said time interval T; (c) sequentially sampling the value of the capacitor at each address in said array by coupling the capacitor to a said detector circuit, applying the voltage input V in a predetermined sampling order to each capacitor in said array, and measuring the sample voltage, v, after said time interval T; (d) providing a processed numerical resultant for each sampled value of each capacitor in said array, said processed numerical resultant being representative of a measured variable per se or of a relational expression of a combination of variables, wherein said variables are selected from v, V, wave form,T and R; and (e) thereafter storing the processed numerical resultant for each address in said array (f) comparing the difference between the stored numerical resultant obtained in step (e) and the said reference value provided in step (a) with said first assigned variation amount; (g) if the compared values from step (f) for two consecutive sampling steps exceeds the first assigned variation amount thereby identifying that the signal is varying in excess of the assigned variation amount; (h) thereafter, reducing the value of said first assigned variation amount to a smaller second assigned variation amount; (i) continuing said comparing steps until two consecutive comparisons for two consecutive sampling steps are greater than said second assigned variation amount and thereby identifying that said analog signal has returned to its normal reference value; and (j) thereafter, increasing the value of said second assigned variation amount to said first assigned variation amount.