US3825816A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dc-to-ac and ac-to-dc converter systems
Assignee: Varco Inc
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Filing: 1973-07-16
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Granted: 1974-07-23
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Expires: 1993-07-16
Abstract
Abstract A signal conversion system wherein variable amplitude, direct current or voltage signals from instrument sensors, which represent the magnitude of measured physical variables by amplitude modulated direct current or voltage signals, are converted to variable amplitude alternating current voltage signals at a frequency determined by the reference signal frequency of the said signal conversion system (usually 60 cycles) (FIG. 1) and a second signal conversion system wherein variable amplitude alternating current signals from instrument sensors, which represent the magnitude of measured physical variables or control signals by amplitude modulated alternating current voltage signals, are converted to variable amplitude direct current or voltage signals (FIG. 2). In both types of conversion, the input signal is filtered for normal mode noise and filtered by a feedback portion of the system for common mode noise. The conversion process also includes mangitude scaling of the variable amplitude input signal, including but not limited to, square root extraction and linear amplitude adjustment.
Inventors
- 👤 M Togneri
- 👤 H Elliott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:43
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/18
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
362 words
A DC to AC converter system which includes a variable magnitude input DC signal that is to be converted to a variable magnitude output AC signal comprising the following interconnected electrical components: said variable magnitude input DC signal being introduced to input isolation and amplification means for electrically isolating the variable magnitude input DC signal from the rest of the system, said input isolation and amplification means being connected between said variable magnitude input DC signal and said output signal rectification, feedback, and function shaping means and said signal chopping means; signal Chopping means through the use of an AC reference signal means to impose a frequency spectrum on the DC signal with the predominant frequency that of the AC reference signal means, said signal chopping means being connected between said input isolation and amplification means and said band pass signal means; band pass filter means for allowing only the preselected frequency component of the chopped input signal from passing to the output amplifier means, said band pass filter means being connected between said signal chopping means and said output amplifier means; output amplifier means for changing the AC signal level to the predetermined AC voltage range, said output amplifier means being connected between said band pass filter means and said output isolator means; output isolator means for electrically isolating the AC signal output from the rest of the system and to provide any further amplification necessary, said output isolator means being connected between said output amplifier means and said variable magnitude output AC signal; output signal rectification, feedback, and function shaping means for rectification of the variable magnitude output AC signal to a variable magnitude DC signal to be used for noise rejection, function shaping by magnitude adjustment and range (span) adjustment, said output signal rectification, feedback, and function shaping means being connected between said variable magnitude output AC signal and said input isolation and amplification means; AC signal reference means for adjustment of the phase of a fixed frequency AC reference signal of the frequency of the AC signal output to the phase of the AC signal output said AC reference signal means being connected to the signal chopping means.
Claim 2
Dependent Claim
362 words
A DC to AC converter system which includes a variable magnitude input DC signal that is to be converted to a variable magnitude output AC signal comprising the following interconnected electrical components: said variable magnitude input DC signal being introduced to input isolation and amplification means for electrically isolating the variable magnitude input DC signal from the rest of the system, said input isolation and amplification means being connected between said variable magnitude input DC signal and said output signal rectification, feedback, and function shaping means and said signal chopping means; signal Chopping means through the use of an AC reference signal means to impose a frequency spectrum on the DC signal with the predominant frequency that of the AC reference signal means, said signal chopping means being connected between said input isolation and amplification means and said band pass signal means; band pass filter means for allowing only the preselected frequency component of the chopped input signal from passing to the output amplifier means, said band pass filter means being connected between said signal chopping means and said output amplifier means; output amplifier means for changing the AC signal level to the predetermined AC voltage range, said output amplifier means being connected between said band pass filter means and said output isolator means; output isolator means for electrically isolating the AC signal output from the rest of the system and to provide any further amplification necessary, said output isolator means being connected between said output amplifier means and said variable magnitude output AC signal; output signal rectification, feedback, and function shaping means for rectification of the variable magnitude output AC signal to a variable magnitude DC signal to be used for noise rejection, function shaping by magnitude adjustment and range (span) adjustment, said output signal rectification, feedback, and function shaping means being connected between said variable magnitude output AC signal and said input isolation and amplification means; AC signal reference means for adjustment of the phase of a fixed frequency AC reference signal of the frequency of the AC signal output to the phase of the AC signal output said AC reference signal means being connected to the signal chopping means.
Claim 3
Dependent Claim
26 words
The DC to AC converter system of claim 1 wherein the said function shaping of the output signal rectification, feedback and function shaping means is equality.
Claim 4
Dependent Claim
29 words
The DC to AC converter system of claim 1 wherein the said function shaping of the output signal rectification, feedback and function shaping means is a square root function.
Claim 5
Dependent Claim
20 words
The DC to AC converter system of claim 1 wherein the said AC reference signal is a sixty Hertz signal.
Claim 6
Dependent Claim
21 words
The DC to AC converter system of claim 4 wherein the said signal filter means filters all but sixty Hertz signals.
Claim 7
Dependent Claim
172 words
A unique AC to DC converter system which includes a variable magnitude AC signal input that is to be converted to a variable magnitude DC signal output comprising the following interconnected electrical components: input isolation means for electrically isolating the variable magnitude input signal from the rest of the system, said input isolation means being connected between said variable magnitude AC signal input and said AC rectification means; AC rectification means for establishing a DC component to the said variable magnitude AC signal input, said AC rectification means being connected between said input isolation means and said function means; function means for signal and magnitude adjustment determined by a predefined function in the system, said function means being connected between said AC rectification means and said output amplifier means; output amplifier means to smooth the said rectified and functionally shaped variable magnitude input AC signal and amplify the said signal to the appropriate output range, said output amplifier means being connected between said function means and said variable magnitude DC signal output.
Claim 8
Dependent Claim
172 words
A unique AC to DC converter system which includes a variable magnitude AC signal input that is to be converted to a variable magnitude DC signal output comprising the following interconnected electrical components: input isolation means for electrically isolating the variable magnitude input signal from the rest of the system, said input isolation means being connected between said variable magnitude AC signal input and said AC rectification means; AC rectification means for establishing a DC component to the said variable magnitude AC signal input, said AC rectification means being connected between said input isolation means and said function means; function means for signal and magnitude adjustment determined by a predefined function in the system, said function means being connected between said AC rectification means and said output amplifier means; output amplifier means to smooth the said rectified and functionally shaped variable magnitude input AC signal and amplify the said signal to the appropriate output range, said output amplifier means being connected between said function means and said variable magnitude DC signal output.
Claim 9
Dependent Claim
16 words
The AC to DC converter system of claim 6 wherein the said function means is equality.
Claim 10
Dependent Claim
19 words
The AC to DC converter system of claim 6 wherein the said function means is a square root function.
Claim 11
Independent Claim
285 words
The method of converting variable magnitude DC signals to corresponding variable magnitude AC signals comprising the steps of: a. feeding the variable magnitude DC signal to an input isolation circuit directly, and B. feeding the variable magnitude AC signal output to the same input isolation circuit through an output signal rectification, feedback, and function shaping circuit; c. producing a functionally shaped, isolated, and amplified signal; d. feeding the said signal of step ''''c'''' to a chopping circuit, and e. feeding an AC reference signal through a phase adjustment circuit to the said chopping circuit; f. producing a frequency spectrum on the said output signal of step ''''c'''' with the predominant frequency that of the said AC reference signal; g. feeding the said produced signal of step ''''f'''' to a band pass filter circuit which is tuned to allow only the frequency of the said AC reference signal to produce an AC signal of corresponding magnitude to the magnitude of the DC input signal at a frequency of the said AC reference signal; h. feeding the said produced signal of step ''''g'''' to an amplifier circuit to produce the necessary voltage to comply with the span specification of the variable magnitude output AC signal after the signal produced by this step is fed into the output isolation circuit; i. feeding the said produced signal of step i ''''h'''' to an output isolation circuit to isolate the produced variable magnitude AC signal from the rest of the circuit, the output of this circuit comprising said variable magnitude AC signal; and j. feeding the said variable magnitude AC signal to a feedback circuit to produce a rectified, functionally shaped, and span amplified signal for use in step ''''b.''''
Claim 12
Independent Claim
285 words
The method of converting variable magnitude DC signals to corresponding variable magnitude AC signals comprising the steps of: a. feeding the variable magnitude DC signal to an input isolation circuit directly, and B. feeding the variable magnitude AC signal output to the same input isolation circuit through an output signal rectification, feedback, and function shaping circuit; c. producing a functionally shaped, isolated, and amplified signal; d. feeding the said signal of step ''''c'''' to a chopping circuit, and e. feeding an AC reference signal through a phase adjustment circuit to the said chopping circuit; f. producing a frequency spectrum on the said output signal of step ''''c'''' with the predominant frequency that of the said AC reference signal; g. feeding the said produced signal of step ''''f'''' to a band pass filter circuit which is tuned to allow only the frequency of the said AC reference signal to produce an AC signal of corresponding magnitude to the magnitude of the DC input signal at a frequency of the said AC reference signal; h. feeding the said produced signal of step ''''g'''' to an amplifier circuit to produce the necessary voltage to comply with the span specification of the variable magnitude output AC signal after the signal produced by this step is fed into the output isolation circuit; i. feeding the said produced signal of step i ''''h'''' to an output isolation circuit to isolate the produced variable magnitude AC signal from the rest of the circuit, the output of this circuit comprising said variable magnitude AC signal; and j. feeding the said variable magnitude AC signal to a feedback circuit to produce a rectified, functionally shaped, and span amplified signal for use in step ''''b.''''
Claim 13
Dependent Claim
16 words
The method of claim 9 wherein the said function shaping circuit is a square root function.
Claim 14
Dependent Claim
13 words
The method of claim 9 wherein the said function shaping circuit is equality.
Claim 15
Independent Claim
139 words
The method of converting variable magnitude AC signal inputs to corresponding variable magnitude DC signal outputs comprising the steps of: a. feeding the variable magnitude AC signal input to an input isolation circuit; b. producing an isolated input signal; c. feeding said isolated input signal to an AC rectification circuit to produce a signal with a DC component; d. feeding the produced signal of step ''''c'''' to a function shaping circuit to produce a magnitude adjustment in the produced signal of step ''''c'''' determined by a predetermined function in the system; and e. feeding the produced signal of step ''''d'''' to an output amplification circuit to smooth the said produced signal of step ''''d'''' to eliminate all of the components except the DC component of said signal, the output of this circuit comprising said variable magnitude DC signal output.
Claim 16
Independent Claim
139 words
The method of converting variable magnitude AC signal inputs to corresponding variable magnitude DC signal outputs comprising the steps of: a. feeding the variable magnitude AC signal input to an input isolation circuit; b. producing an isolated input signal; c. feeding said isolated input signal to an AC rectification circuit to produce a signal with a DC component; d. feeding the produced signal of step ''''c'''' to a function shaping circuit to produce a magnitude adjustment in the produced signal of step ''''c'''' determined by a predetermined function in the system; and e. feeding the produced signal of step ''''d'''' to an output amplification circuit to smooth the said produced signal of step ''''d'''' to eliminate all of the components except the DC component of said signal, the output of this circuit comprising said variable magnitude DC signal output.
Claim 17
Dependent Claim
12 words
The method of claim 12 wherein the said function circuit is equality.
Claim 18
Dependent Claim
15 words
The method of claim 12 wherein the said function circuit is a square root circuit.
Claim 19
Dependent Claim
434 words
A DC to AC converter system which includes a variable magnitude input DC signal that is to be converted to a variable magnitude output AC signal comprisng the following interconnected electrical components: said variable magnitude input DC signal being introduced to input isolation and amplification means for electrically isolating the variable magnitude input DC signal from the rest of the system, said input isolation and amplification means being connected between said variable magnitude input DC signal and said output signal rectification, feedback, and function shaping means and said signal chopping means; signal chopping means through the use of an AC reference signal means to impose a frequency spectrum on the DC signal with the predominant frequency that of the AC reference signal means, said signal chopping means being connected between said input isolation and amplification means and said band pass signal means; band pass filter means for allowing only the preselected frequency component of the chopped input signal from passing to the output amplifier means, said band pass filter means beiNg connected between said signal chopping means and said output amplifier means; output amplifier means for changing the AC signal level to the predetermined AC voltage range, said output amplifier means being connected between said band pass filter means and said output isolator means; output isolator means for electrically isolating the AC signal output from the rest of the system and to provide any further amplification necessary, said output isolator means being connected between said output amplifier means and said variable magnitude output AC signal; output signal rectification, feedback, and function shaping means for rectification of the variable magnitude output AC signal to a variable magnitude DC signal to be used for noise rejection, function shaping by magnitude adjustment and range (span) adjustment, said output signal rectification, feedback, and function shaping means being connected between said variable magnitude output AC signal and said input isolation and amplification means; AC signal reference means for adjustment of the phase of a fixed frequency AC reference signal of the frequency of the AC signal output to the phase of the AC signal output said AC reference signal means being connected to the signal chopping means; feedback amplifier and integrator means for smoothing the output of the output signal rectification, feedback and function shaping means thereby reproducing the said variable magnitude input DC signal without noise but with function shaping, said feedback amplifier and integrator means being connected to said output signal rectification, feedback and function shaping means and producing a variable magnitude DC signal corresponding to the said variable magnitude input DC signal with function shaping imposed.
Claim 20
Dependent Claim
434 words
A DC to AC converter system which includes a variable magnitude input DC signal that is to be converted to a variable magnitude output AC signal comprisng the following interconnected electrical components: said variable magnitude input DC signal being introduced to input isolation and amplification means for electrically isolating the variable magnitude input DC signal from the rest of the system, said input isolation and amplification means being connected between said variable magnitude input DC signal and said output signal rectification, feedback, and function shaping means and said signal chopping means; signal chopping means through the use of an AC reference signal means to impose a frequency spectrum on the DC signal with the predominant frequency that of the AC reference signal means, said signal chopping means being connected between said input isolation and amplification means and said band pass signal means; band pass filter means for allowing only the preselected frequency component of the chopped input signal from passing to the output amplifier means, said band pass filter means beiNg connected between said signal chopping means and said output amplifier means; output amplifier means for changing the AC signal level to the predetermined AC voltage range, said output amplifier means being connected between said band pass filter means and said output isolator means; output isolator means for electrically isolating the AC signal output from the rest of the system and to provide any further amplification necessary, said output isolator means being connected between said output amplifier means and said variable magnitude output AC signal; output signal rectification, feedback, and function shaping means for rectification of the variable magnitude output AC signal to a variable magnitude DC signal to be used for noise rejection, function shaping by magnitude adjustment and range (span) adjustment, said output signal rectification, feedback, and function shaping means being connected between said variable magnitude output AC signal and said input isolation and amplification means; AC signal reference means for adjustment of the phase of a fixed frequency AC reference signal of the frequency of the AC signal output to the phase of the AC signal output said AC reference signal means being connected to the signal chopping means; feedback amplifier and integrator means for smoothing the output of the output signal rectification, feedback and function shaping means thereby reproducing the said variable magnitude input DC signal without noise but with function shaping, said feedback amplifier and integrator means being connected to said output signal rectification, feedback and function shaping means and producing a variable magnitude DC signal corresponding to the said variable magnitude input DC signal with function shaping imposed.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-22 | 1978-01-21 | 1978-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-22 | 1982-01-21 | 1982-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-22 | 1986-01-21 | 1986-07-23 | $7700.00 | Window Closed / Lapsed |