US3916023A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing isotropic foamed stock
Assignee: Pharmacia and Upjohn Co
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Filing: 1972-10-03
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Granted: 1975-10-28
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Expires: 1992-10-03
Abstract
Abstract An improved one-shot system and process for producing polyurethane foam stock and the like, including measurement circuits for deriving digital measurements of parameters such as the mass transfer rates of the various constituents, and further including an automatic controller system responsive to such measurements for adjusting and controlling the parameters with respect to preselected values. A controller system is provided for continuously sampling the various incoming measurement signals sequentially, and for deriving error signals from a comparison of various functional relationships of the samples relative to pre-established optimums. Control circuits are also included for continually adjusting the operation of the system in response to the error signals.
Inventors
- 👤 Lawrence C Porter
- 👤 Kenneth E Graves
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 01:42
CPC Classifications
G; G05; G05D; G05D11/00; G05D11/02; G05D11/13; G05D11/131; G05D11/132; B; B29; B29C; B29C44/00; B29C44/34; B29C44/60; Y; Y10; Y10S; Y10S261/00; Y10S261/26; Y10S264/00; Y10S264/13; Y10S521/00; Y10S521/917
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
174 words
IN A ONE-SHOT PROCESS FOR COMMINGLING A MASTER REACTANT AND A PLURALITY OF OTHER LIQUID REACTANTS INCLUDING RESIN ISOCYANATE, CATALYST, AND A BLOWING AGENT ACCORDING TO A PRESELECTED FORMULATION, THE METHOD OF ESTABLISHING AND MAINTAINING THE PROPORTIONS OF SAID REACTANTS ACCORDING TO SAID FORMULATION COMPRISING THE STEPS OF ELECTRICALLY ESTABLISHING A PLURALITY OF PRESET VALUES EACH CORRESPONDING TO A PRESELECTED RATIO OF ONE OF SAID OTHER REACTANTS TO SAID MASTER REACTANT, GENERATING A PLURALITY OF DIFFERENT MEASUREMENTS SIGNALS EACH CORRESPONDING TO AND COMPOSED OF ELECTRICAL PULSE FUNCTIONALLY RELATED TO MASS TRANFER UNITS OF SAID MASTER AND SAID OTHER REACTANTS, DERIVING AN ELECTRICAL SIGNAL COMPOSED OF PULSES CORRESPONDING IN NUMBER TO THE ACTUAL RATIO OF EACH OF SAID OTHER REACTANTS TO SAID MASTER REACTANT IN SAID PROCESS AS A FUNCTION OF THE NUMBER OF PULSES IN SAID MEASUREMENT SIGNAALS, AND INCREMENTALLY ADJUSTING THE INPUT OF EACH OF SAID REACTANTS INTO SAID PROCESS AS A FUNCTION OF ANY DIFFERENCE BETWEEN THE ACTUAL RAITO OF SAID REACTANT TO SAID MASTER REACTANT AND THE PRESET VALUE CORRESPONDING THERETO.
Claim 2
Dependent Claim
174 words
IN A ONE-SHOT PROCESS FOR COMMINGLING A MASTER REACTANT AND A PLURALITY OF OTHER LIQUID REACTANTS INCLUDING RESIN ISOCYANATE, CATALYST, AND A BLOWING AGENT ACCORDING TO A PRESELECTED FORMULATION, THE METHOD OF ESTABLISHING AND MAINTAINING THE PROPORTIONS OF SAID REACTANTS ACCORDING TO SAID FORMULATION COMPRISING THE STEPS OF ELECTRICALLY ESTABLISHING A PLURALITY OF PRESET VALUES EACH CORRESPONDING TO A PRESELECTED RATIO OF ONE OF SAID OTHER REACTANTS TO SAID MASTER REACTANT, GENERATING A PLURALITY OF DIFFERENT MEASUREMENTS SIGNALS EACH CORRESPONDING TO AND COMPOSED OF ELECTRICAL PULSE FUNCTIONALLY RELATED TO MASS TRANFER UNITS OF SAID MASTER AND SAID OTHER REACTANTS, DERIVING AN ELECTRICAL SIGNAL COMPOSED OF PULSES CORRESPONDING IN NUMBER TO THE ACTUAL RATIO OF EACH OF SAID OTHER REACTANTS TO SAID MASTER REACTANT IN SAID PROCESS AS A FUNCTION OF THE NUMBER OF PULSES IN SAID MEASUREMENT SIGNAALS, AND INCREMENTALLY ADJUSTING THE INPUT OF EACH OF SAID REACTANTS INTO SAID PROCESS AS A FUNCTION OF ANY DIFFERENCE BETWEEN THE ACTUAL RAITO OF SAID REACTANT TO SAID MASTER REACTANT AND THE PRESET VALUE CORRESPONDING THERETO.
Claim 3
Dependent Claim
100 words
The method described in claim 1, further comprising establishing a ratio period as a function of a preselected number of pulses in said measurement signal corresponding to said master reactant, determining the total number of pulses generated in a portion of each of said measurement signals corresponding to said other reactants, comparing each of said totals with the corresponding preset value, deriving ratio error pulses corresponding in number to any difference between any of said totals with its corresponding preset value, and incrementally adjusting the input of the corresponding reactant into said process in response to said ratio error pulses.
Claim 4
Dependent Claim
57 words
The method described in claim 2, wherein said incrementally adjusting step comprises changing the input of reactant into said process by one mass transfer unit of the corresponding reactant for each ratio error pulse resulting from a comparison of the actual ratio of said reactant to said master reactant and the corresponding one of said preset values.
Claim 5
Dependent Claim
116 words
The method described in claim 3, further comprising monitoring and sorting the pulses in each of said signals during a predetermined sample interval, counting out a preselected total number of sorted pulses from the measurement signal corresponding to said master reactant to establish said ratio period subsisting with but independent of the length of said sample interval, counting the total number of pulses occurring in each of said other measurement signals during said ratio period, comparing the total counted from each of said other measurement signals with the preset value corresponding to said measurement signal, and deriving ratio error pulses independently of the length of said sample interval and as a function of said ratio period.
Claim 6
Dependent Claim
29 words
The method described in claim 4, wherein pulses in said other measurement signals are totalled and such totals are compared with said preset values according to a predetermined sequence.
Claim 7
Dependent Claim
124 words
The method described in claim 5, further comprising electrically establishing an additional totalize preset value representing the preselected total reactant sought to be passed through said process during said sample interval, electrically deriving a function of the total number of pulses generated in all of said measurement signals during said sample interval as an indication of the total reactant actually passed through said process during said sample interval, comparing said derived function of said total number of measurement pulses with said totalize preset value, deriving totalize error pulses in relationship to any difference between said derived function of said total number of pulses and said totalize preset value, and incrementally adjusting the input of said master reactant in response to said totalize error pulses.
Claim 8
Dependent Claim
48 words
The method described in claim 6, further comprising incrementally adjusting the input of said master reactant by one mass transfer unit thereof in response to each ratio error pulse derived from a comparison of the actual ratio of said reactant to the corresponding one of said preset values.
Claim 9
Dependent Claim
103 words
The method described in claim 7, further comprising generating the pulses in one of said measurement signals corresponding to one of said other reactants as a function of mass transfer units of a first preselected magnitude, generating the pulses in another of said measurement signals corresponding to another of said other reactants as a function of mass transfer units of a second different preselected magnitude, and deriving said function of the total of all of said pulses in said measurement signals generated during said sample interval as a weighted total corresponding to the total amount of material throughput occurring during said sample interval.
Claim 10
Dependent Claim
69 words
The method described in claim 8, further comprising providing said ratio Error pulses as a function of the magnitude of the mass transfer units represented by said pulses corresponding to said master reactant, and incrementally adjusting the input of each of said other reactants as a function of the magnitude of the mass transfer units represented by the pulses in the measurement signal corresponding to the reactant so adjusted.
Claim 11
Dependent Claim
72 words
The method described in claim 9, further comprising multiplying said ratio error pulses as a function of the magnitude of the mass transfer units represented by the counted measurement pulses related thereto and the magnitude of the mass transfer units represented by the pulses corresponding to said master reactant, and incrementally adjusting the input of the reactant corresponding to said counted measurement pulses by the product of said multiplied ratio error pulses.
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) | 1978-10-27 | 1979-04-28 | 1979-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-27 | 1983-04-28 | 1983-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-27 | 1987-04-28 | 1987-10-28 | $7700.00 | Window Closed / Lapsed |