US3881670A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system with dual unmonitored condition sensors and fail operative characteristics
Assignee: Bendix Corp
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Filing: 1973-12-07
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Granted: 1975-05-06
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Expires: 1993-12-07
Abstract
Abstract A fail operative control system equipped with dual unmonitored condition sensors which would otherwise render the system fail passive or fail safe. The fail operative feature is achieved in response to signals from the unmonitored sensors and a signal from another sensor, and which signal is essentially the first derivative of the signals from the unmonitored sensors.
Inventors
- 👤 Jerry Doniger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:48
CPC Classifications
G; G05; G05D; G05D1/00; G05D1/0055; G05D1/0077
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
255 words
A fail operative control system, comprising: means for providing a first signal corresponding to a condition; means for providing a second redundant signal corresponding to the condition; means for providing a reference signal; means for combining the first signal and the reference signal and for providing a first error signal; means for combining the second signal and the reference signal and for providing a second error signal; means for providing a signal corresponding to the rate of change of the condition; averaging means connected to both of said combining means and to the condition rate signal means and responsive to the first and second error signals and the rate signal for providing an output signal corresponding to the average of the acceptable error and rate signals and for eliminating those of said signals which differ from the average by a predetermined amount; integrating means connected to the means for providing a signal corresponding to the rate of change of the condition for integrating the signal therefrom and for providing a signal as a pseudo-condition reference; averaging means connected to both of said combining means and to the integrating mEans and responsive to the first and second error signals and the pseudo-condition reference signal for providing the output signal corresponding to the average of the acceptable error and pseudo-condition reference signals and for eliminating those of said signals which differ from the average by a predetermined amount and means connected to the last mentioned means and responsive to the output signal therefrom for controlling the condition.
Claim 2
Dependent Claim
255 words
A fail operative control system, comprising: means for providing a first signal corresponding to a condition; means for providing a second redundant signal corresponding to the condition; means for providing a reference signal; means for combining the first signal and the reference signal and for providing a first error signal; means for combining the second signal and the reference signal and for providing a second error signal; means for providing a signal corresponding to the rate of change of the condition; averaging means connected to both of said combining means and to the condition rate signal means and responsive to the first and second error signals and the rate signal for providing an output signal corresponding to the average of the acceptable error and rate signals and for eliminating those of said signals which differ from the average by a predetermined amount; integrating means connected to the means for providing a signal corresponding to the rate of change of the condition for integrating the signal therefrom and for providing a signal as a pseudo-condition reference; averaging means connected to both of said combining means and to the integrating mEans and responsive to the first and second error signals and the pseudo-condition reference signal for providing the output signal corresponding to the average of the acceptable error and pseudo-condition reference signals and for eliminating those of said signals which differ from the average by a predetermined amount and means connected to the last mentioned means and responsive to the output signal therefrom for controlling the condition.
Claim 3
Dependent Claim
126 words
A system as described by claim 1, including: the averaging means having a first comparator for comparing the first error signal to the output signal and for providing a first output when said signals differ by a predetermined amount, a second comparator for comparing the second error signal to the output signal and for providing a second output when said signals differ by a predetermined amount, and a third comparator for comparing the pseudo-condition reference signal to the output signal and for providing a third output when said signals differ by a predetermined amount; and means connected to the averaging means and responsive to the first, second and third outputs from the first, second and third comparators, for displaying unacceptable error and pseudo-condition reference signal conditions.
Claim 4
Dependent Claim
143 words
A system as described by claim 1, including: the averaging means having a first comparator for comparing the first error signal to the output signal and for providing a first output when said signals differ by a predetermined amount, a second comparator for comparing the second error signal to the output signal and for providing a second output when said signals differ by a predetermined amount, and a third comparator for comparing the pseudo-condition reference signal to the output signal and for providing a third output when said signals differ by a predetermined amount; and means connected to the averaging means and to the condition controlling means and responsive to the first, second and third outputs from the first, second and third comparators for disengaging the controlling means when said outputs are commensurate with a predetermined unacceptable error and pseudo-condition reference signal condition.
Claim 5
Dependent Claim
55 words
A system as described by claim 1, including: feedback means connected to the integrating means; and the feedback means connected to the averaging means and applying the output signal therefrom to the integrating means for driving the integrating means so that the pseudo-condition reference signal from the integrating means follows the averaging means output signal.
Claim 6
Dependent Claim
70 words
A system as described by claim 4, wherein the feedback means includes: a difference amplifier connected to the integrating means and to the averaging means for providing a signal corresponding to the difference between the pseudo-condition reference and averaging means output signals; and a limiter connected to the difference amplifier and to the integrating means for limiting the difference signal and for applying said limited signal to the integrating means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |