Patent US3849056A successfully refreshed from Google Patents.
US3849056A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Computer based plant protection system
Assignee: Combustion Engineering Inc
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Filing: 1972-11-02
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Granted: 1974-11-19
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Expires: 1992-11-02
Abstract
Abstract A plant protection system and technique utilizing a plurality of programmable controllers interconnected in a hierarchy arrangement is disclosed. A first plurality of ''''lower'''' level controllers receive signals commensurate with groups of sensed process parameters and employ these signals to generate safetycheck signals indicative of the state of that portion of the plant with which each individual controller is associated. These safety-check signals are delivered to each of a pair of ''''higher'''' level programmable controllers which redundantly compute the need to terminate the entire process; the ''''higher'''' level controllers also checking the operability of the lower level controllers and the lower level controllers ''''voting'''' in the process termination computation.
Inventors
- 👤 J Schuss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:20
CPC Classifications
G; G05; G05B; G05B9/00; G05B9/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
301 words
A protection system for a furnace, the furnace having a plurality of burners and associated ignitors situated at each of a plurality of vertically displaced elevations, condition responsive signal generators being associated with each furnace elevation for providing signals commensurate with the state of the burners and ignitors and the presence of flame, said protection system comprising: a plurality of first programmable controllers, each of said controllers of said first plurality being associated with one of said furnace burner elevations and receiving signals commensurate with the state of the burners and ignitors at that elevation and the presence or absence of flame, each of said controllers of said first plurality providing output signals for controlling the ignitors and burners at the associated elevation in accordance with the received signals and a stored program, each of said contrOllers of said first plurality further generating an arming signal commensurate with the condition of flame desired and a flame failure signal; a second programmable controller, said second controller being responsive to the arming and flame failure signals generated by each of said controllers of said first plurality for generating a control signal for terminating furnace operation when the arming and flame failure signals from all of said first controllers indicate unsafe operating conditions; a third programmable controller, said third programmable controller being responsive to the arming and flame failure signals generated by each of said controllers of said first plurality for generating a control signal for terminating furnace operation when the arming and flame failure signals from all of said first controllers indicate unsafe operating conditions; means for delivering the arming and flame failure signals provided by each of said controllers of said first plurality to said second and third controllers; and means connecting the outputs of said second and third controllers in parallel.
Claim 2
Dependent Claim
301 words
A protection system for a furnace, the furnace having a plurality of burners and associated ignitors situated at each of a plurality of vertically displaced elevations, condition responsive signal generators being associated with each furnace elevation for providing signals commensurate with the state of the burners and ignitors and the presence of flame, said protection system comprising: a plurality of first programmable controllers, each of said controllers of said first plurality being associated with one of said furnace burner elevations and receiving signals commensurate with the state of the burners and ignitors at that elevation and the presence or absence of flame, each of said controllers of said first plurality providing output signals for controlling the ignitors and burners at the associated elevation in accordance with the received signals and a stored program, each of said contrOllers of said first plurality further generating an arming signal commensurate with the condition of flame desired and a flame failure signal; a second programmable controller, said second controller being responsive to the arming and flame failure signals generated by each of said controllers of said first plurality for generating a control signal for terminating furnace operation when the arming and flame failure signals from all of said first controllers indicate unsafe operating conditions; a third programmable controller, said third programmable controller being responsive to the arming and flame failure signals generated by each of said controllers of said first plurality for generating a control signal for terminating furnace operation when the arming and flame failure signals from all of said first controllers indicate unsafe operating conditions; means for delivering the arming and flame failure signals provided by each of said controllers of said first plurality to said second and third controllers; and means connecting the outputs of said second and third controllers in parallel.
Claim 3
Dependent Claim
147 words
The apparatus of claim 1 wherein each of said controllers of said first plurality includes self-checking means for providing an output signal commensurate with a controller malfunction or power loss and wherein the signal commensurate with a preselected ratio of actual to rated plant operating capacity is generated and delivered to each of said second and third controllers, said apparatus further comprising: means for delivering said malfunction or power loss signals from each of said controllers of said first plurality to each of said second and third controllers; and wherein said second and third controllers each further comprise: means responsive to said malfunction or power loss signals and to said signal commensurate with the preselected ratio for generating a disabling signal for an elevation having a controller malfunction or power loss when the plant is operating at a capacity less than that commensurate with said preselected ratio.
Claim 4
Dependent Claim
48 words
The apparatus of claim 2 further comprising: means for generating signals commensurate with the availability of power for driving the actuators associated with each controller of said first plurality; and means for delivering said power availability signals as further inputs to each of said second and third controllers.
Claim 5
Dependent Claim
66 words
The apparatus of claim 3 wherein said second and third controllers each further comprise: means responsive to said power availability signals and said signal commensurate with the preselected operating capacity ratio for generating process termination signals when power is unavailable for operating the actuators associated with each of said first controllers and the plant is operating at a level below that commensurate with said preselected ratio.
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) | 1977-11-18 | 1978-05-20 | 1978-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-18 | 1982-05-20 | 1982-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-18 | 1986-05-20 | 1986-11-19 | $7700.00 | Window Closed / Lapsed |