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US2934279A Expired / Lapsed US ⏱️ 0.0 years remaining

Production of groundwood pulp

Assignee: 3M Co
•
Filing: 1955-06-29
•
Granted: 1960-04-26
•
Expires: 1975-06-29
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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 13:28
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

References Cited (Backward Citations)

DE49672C Cited
US253654A Cited
US349992A Cited
US860367A Cited
US947491A Cited
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US2575656A Cited

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

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