US3343818A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making gypsum board
Assignee: National Gypsum Co
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Filing: 1966-06-14
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Granted: 1967-09-26
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Expires: 1986-06-14
Abstract
No abstract record available.
Inventors
- 👤 Henry F Plemous
- 👤 Marvin D S Fields
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:57
CPC Classifications
C; C04; C04B; C04B38/00; C04B38/10; C04B38/106; B; B28; B28B; B28B19/00; B28B19/0092; B28C; B28C5/00; B28C5/08; B28C5/0881; B28C7/00; B28C7/04; B28C7/0404; B28C7/0418
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
131 words
THE METHOD OF MAKING PAPER-COVERED GYPSUM-CORE WALLBOARD COMPRISING THE STEPS OF FEEDING A SUBSTANTIALLY CONSTANT SUPPLY OF CALCINED GYPSUM, FINE TENACIOUS FOAM, WATER, AND OTHER ADDITIVES TO A MECHANICAL MIXER HAVING READILY CONTROLLABLE VARIABLE SPEED MECHANICAL MIXING MEANS, ADJUSTING THE SPEED OF SAID MECHANICAL MIXING MEANS TO ABOUT 1% TO 25% GREATER THAN THE SPEED AT WHICH SAID INGREDIENTS ARE THOROUGHLY MIXED WITH AN OPTIMUM RETENTION OF THE ENTRAINED AIR OF SAID FOAM, AND ADJUSTING THE RATE OF ADDITION OF SAID FOAM TO PROVIDE AN AMOUNT OF EXCESS ENTRAINED AIR TO EQUAL THE AMOUNT THAT WILL BE KNOCKED OUT BY SAID SPEED BEING GREATER THAN THE SPEED OF OPTIMUM FOAM RETENTION, WHEREBY THE VOLUME OF MIXED MATERIALS MAY BE VARIED BY AN INVERSE ADJUSTMENT OF SAID VARIABLE SPEED MECHANICAL MIXING MEANS.
Claim 2
Independent Claim
131 words
THE METHOD OF MAKING PAPER-COVERED GYPSUM-CORE WALLBOARD COMPRISING THE STEPS OF FEEDING A SUBSTANTIALLY CONSTANT SUPPLY OF CALCINED GYPSUM, FINE TENACIOUS FOAM, WATER, AND OTHER ADDITIVES TO A MECHANICAL MIXER HAVING READILY CONTROLLABLE VARIABLE SPEED MECHANICAL MIXING MEANS, ADJUSTING THE SPEED OF SAID MECHANICAL MIXING MEANS TO ABOUT 1% TO 25% GREATER THAN THE SPEED AT WHICH SAID INGREDIENTS ARE THOROUGHLY MIXED WITH AN OPTIMUM RETENTION OF THE ENTRAINED AIR OF SAID FOAM, AND ADJUSTING THE RATE OF ADDITION OF SAID FOAM TO PROVIDE AN AMOUNT OF EXCESS ENTRAINED AIR TO EQUAL THE AMOUNT THAT WILL BE KNOCKED OUT BY SAID SPEED BEING GREATER THAN THE SPEED OF OPTIMUM FOAM RETENTION, WHEREBY THE VOLUME OF MIXED MATERIALS MAY BE VARIED BY AN INVERSE ADJUSTMENT OF SAID VARIABLE SPEED MECHANICAL MIXING 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) | 1970-09-25 | 1971-03-27 | 1971-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-09-25 | 1975-03-27 | 1975-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-09-25 | 1979-03-27 | 1979-09-26 | $7700.00 | Window Closed / Lapsed |