Patent US2934279A successfully refreshed from Google Patents.
US2934279A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of groundwood pulp
Assignee: 3M Co
•
Filing: 1955-06-29
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Granted: 1960-04-26
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Expires: 1975-06-29
Abstract
No abstract record available.
Inventors
- 👤 Leonard R Nestor
- 👤 Page Robert A Le
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:10
CPC Classifications
B; B27; B27L; B27L11/00; B27L11/06; B02; B02C; B02C19/00; B02C19/0056
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
122 words
APPARATUS FOR THE PREPARATION OF FIBROUS PULP FROM WOOD BY CONTROLLED LONGITUDINAL GRINDING, COMPRISING IN COMBINATION: AN OPEN-FACED GRIT-COATED GRINDING-BELT, PULLEYS FOR SUPPORTING AND DRIVING SAID BELT, A FLAT BACK-UP PLATE CONTACTISNG THE GRIT-FREE SIDE OF A FLAT PORTION OF THE BELT, A HOPPER ADJACENT THE GRIT-COATED SIDE OF THE BELT OPPOSITE SAID BACK-UP PLATE, AND INCLUDING SIDES PARALLEL TO THE DIRECTION OF ADVANCE OF SAID BELT, A THRUST PLATE FOR PREVENTING LOSS OF SUBSTANTIAL SECTIONS OF UNGROUND WOOD FROM THE HOPPER DURING GRINDING, AND A PRESSURE PLATE FOR FORCING WOOD BILLETS IN SAID HOPPER AGAINST SAID GRINDING-BELT, SAID PRESSURE PLATE BEING ADJUSTABLE AS TO ANGLE OF ATTACK, SPRAY NOZZLES FOR DIRECTING WATER AT HIGH VELOCITY AGAINST SAID GRINDING-BELT TO REMOVE GROUND
Claim 2
Dependent Claim
122 words
APPARATUS FOR THE PREPARATION OF FIBROUS PULP FROM WOOD BY CONTROLLED LONGITUDINAL GRINDING, COMPRISING IN COMBINATION: AN OPEN-FACED GRIT-COATED GRINDING-BELT, PULLEYS FOR SUPPORTING AND DRIVING SAID BELT, A FLAT BACK-UP PLATE CONTACTISNG THE GRIT-FREE SIDE OF A FLAT PORTION OF THE BELT, A HOPPER ADJACENT THE GRIT-COATED SIDE OF THE BELT OPPOSITE SAID BACK-UP PLATE, AND INCLUDING SIDES PARALLEL TO THE DIRECTION OF ADVANCE OF SAID BELT, A THRUST PLATE FOR PREVENTING LOSS OF SUBSTANTIAL SECTIONS OF UNGROUND WOOD FROM THE HOPPER DURING GRINDING, AND A PRESSURE PLATE FOR FORCING WOOD BILLETS IN SAID HOPPER AGAINST SAID GRINDING-BELT, SAID PRESSURE PLATE BEING ADJUSTABLE AS TO ANGLE OF ATTACK, SPRAY NOZZLES FOR DIRECTING WATER AT HIGH VELOCITY AGAINST SAID GRINDING-BELT TO REMOVE GROUND
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-04-26 | 1963-10-26 | 1964-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-04-26 | 1967-10-26 | 1968-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-04-26 | 1971-10-26 | 1972-04-26 | $7700.00 | Window Closed / Lapsed |