Anticipatory control of headbox slice opening in a paper machine
Abstract
Abstract A HEADBOX OF A MACHINE PRODUCING A FIBROUS SHEET HAS A SLICE OPENING CONTROLLED IN RESPONSE TO SIGNALS INDICATIVE OF TOTAL HEAD OF FLUID IN THE HEADBOX, THE RATE OF FLOW OF A FIBROUS SLURRY INTO THE HEADBOX AND THE SPEED OF A FOURDRINIER WIRE RECEIVING A JET OF SLURRY EMERGING FROM THE HEADBOX SLICE. THE SLICE OPENING IS CONTROLLED TO AFFECT FORMATION OF THE FIBROUS SHEET ON THE WIRE. CONSISTENCY OF THE SLURRY BEING FED INTO THE HEADBOX IS VARIED TO CONTROL THE POSITION OF A DRY LINE ON THE WIRE OF FORMATION OF FIBERS ON THE WIRE. THE LEVEL OF LIQUID IN THE HEADBOX IS MAINTAINED AT A PREDETERMINED LEVEL BY A CONTROLLER. THE SLICE OPENING IS CONTROLLED IN ANTICIPATORY MANNER TO COMPENSATE FOR THE SLOW RESPONSE OF THE TOTAL HEAD IN THE HEADBOX TO CHANGES OCCURING IN RESPONSE TO THE SLURRY MASS FLOW RATE INTO AND OUT OF THE HEADBOX. THE CONTROLLER FOR THE SLICE OPENING IS PROVIDED WITH DEADBAND.
Inventors
- 👤 James S Rice
Bibliographic Details
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1975-11-21 | 1976-05-22 | 1976-11-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-11-21 | 1980-05-22 | 1980-11-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-11-21 | 1984-05-22 | 1984-11-21 | $7700.00 | Window Closed / Lapsed |