US3786242A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process control simulator
Assignee: Individual
•
Filing: 1971-09-23
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Granted: 1974-01-15
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Expires: 1991-09-23
Abstract
Abstract A process control simulator contains electronic circuits for modifying set-point control signals by summing, integrating, differentiating and introducing step functions on continuous, single or periodic bases to determine off-line the behavior of a process control system. Provisions are made for several interacting control loops, for dead-time delays and for faster than actual response times to speed up simulation. The dead-time delays are provided by scanning a set of storage capacitors with a variable speed scanning motor through a scanning control cycle of operation. A three control loop controller section provides for setting the gain of the controller system and controlling integration and difference modes responsive to step disturbances introduced into an integration process after a selectable dead-time adjustment. The output signal is reproduced in the form of a process response waveform. Provisions are made for smoothing readout and responding to sluggish systems by a slow sampling technique. An automatic zero adjust circuit is provided to compensate for drift once each operation cycle and is controlled by a logic circuit.
Inventors
- 👤 H Brooks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:28
CPC Classifications
G; G06; G06G; G06G7/00; G06G7/48; G06G7/66; G05; G05B; G05B17/00; G05B17/02
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
125 words
A process control simulation instrument providing in combination, a multiple-process controller section adapted to convert an input voltage signal to a modified output signal voltage by operation of at least two interacting signal modification circuits providing a modified output signal, and processor equipment including a step disturbance source for introducing step functions of pre-determined amplitude into the modified output signal, a dead time source comprising storage means connected to said two interacting circuits for holding the modified signal at a plurality of discrete time intervals, sampling means for reading the stored signal after a specified periodic dead-time and means connected to modify the input signal voltage with the sampled stored signal thereby introducing the recalled stored signal into said signal modification circuits to interact therein.
Claim 2
Dependent Claim
125 words
A process control simulation instrument providing in combination, a multiple-process controller section adapted to convert an input voltage signal to a modified output signal voltage by operation of at least two interacting signal modification circuits providing a modified output signal, and processor equipment including a step disturbance source for introducing step functions of pre-determined amplitude into the modified output signal, a dead time source comprising storage means connected to said two interacting circuits for holding the modified signal at a plurality of discrete time intervals, sampling means for reading the stored signal after a specified periodic dead-time and means connected to modify the input signal voltage with the sampled stored signal thereby introducing the recalled stored signal into said signal modification circuits to interact therein.
Claim 3
Dependent Claim
42 words
An instrument as provided in claim 1 wherein the two interacting signal modification circuits of the controller section comprise an integrator device, a derivative device, and means to introduce the signal and to control simultaneously the input signal level to said devices.
Claim 4
Dependent Claim
20 words
An instrument as provided in claim 1 wherein the the processor equipment includes lag integration means processing said modified signal.
Claim 5
Dependent Claim
32 words
An instrument as defined in claim 3 wherein the integration means includes a selectable control and circuits selected thereby for operation of the integration means selectively in open and closed loop configurations.
Claim 6
Dependent Claim
54 words
An instrument as defined in claim 1 including readout circuit means adapted to take a succession of signals from said storage means at different ones of said discrete time intervals, and circuitry connected for processing the succession of signals for smoothing out the interpolation from one of said discrete time intervals to the next.
Claim 7
Dependent Claim
33 words
An instrument as defined in claim 1 wherein said sampling means for sampling selected ones of the signals stored by said storage means samples at less than all of said discrete time intervals.
Claim 8
Dependent Claim
75 words
An instrument as defined in claim 1 including at least one operational amplifier having input and output signal paths processing a signal within said instrument, and zero adjust means including a capacitor connected in series with the input signal path of the operational amplifier and periodically operable correction means transferring the capacitor temporarily across said amplifier input and output paths in opposed polarity to receive errors for reintroduction in series with the input signal path.
Claim 9
Dependent Claim
28 words
The instrument defined in claim 7, wherein the dead-time source provides a dead-time cycle of known duration and the zero adjust means operates cyclically once per dead-time cycle.
Claim 10
Dependent Claim
19 words
An instrument as defined in claim 7 wherein several operational amplifiers are employed each including said zero adjust means.
Claim 11
Dependent Claim
21 words
The instrument defined in claim 1 including control means for said recalling means permitting continuously variable choice of the dead-time interval.
Claim 12
Dependent Claim
18 words
The instrument defined in claim 10 wherein said control means comprises a motor and speed control means therefor.
Claim 13
Dependent Claim
43 words
The instrument defined in claim 11 wherein said storage means comprises at least one set of capacitors and a switch scanned by said motor to connect different capacitors one at a time into circuit positions to receive and read out the stored signals.
Claim 14
Dependent Claim
36 words
The instrument defined in claim 12 wherein said storage means includes two sets of capacitors, and two switches, and means synchronized with said motor to alternately connect capacitors from the two sets into said circuit positions.
Claim 15
Dependent Claim
33 words
The instrument defined in claim 12 including a high-impedance amplifier coupled to read out the signals stored by said capacitors having a field effect transistor input stage and a Darlington Pair output stage.
Claim 16
Dependent Claim
33 words
The instrument defined in claim 12 including at least one operational amplifier having input and output signal paths and means connected therein to compare input and output signals thereby to correct drift errors.
Claim 17
Dependent Claim
21 words
An instrument as defined in claim 15 including switch means connected to optionally reset the signal input level to said amplifier.
Claim 18
Dependent Claim
31 words
A process control instrument as defined in claim 1 with a two channel recorder, and means connecting said input and output signals to produce recordings on different recorder channels for comparison.
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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) | 1977-01-14 | 1977-07-16 | 1978-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-14 | 1981-07-16 | 1982-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-14 | 1985-07-16 | 1986-01-15 | $7700.00 | Window Closed / Lapsed |