US3116245A
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Assignee: Walker Manufacturing Co
•
Filing: 1958-07-23
•
Granted: 1963-12-31
•
Expires: 1978-07-23
Abstract
No abstract record available.
Inventors
- 👤 Robert W Mcnabb
- 👤 Howard L Dahlstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:53
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/1607; B01D39/1615; B01D29/00; B01D29/11; B01D29/111; B01D29/13; B01D29/15; B01D29/21
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
158 words
A FILTER MATERIAL COMPRISING MONOLITHIC SHEET OF PURIFIED ALPHA CELLULOSE PULP FORMED OF SECOND CUT COTTOM LINTERS FIBERS OF APPROXIMATELY 2 MM. OR LESS AVERAGE LENGTH AND HAVING A WIRE SIDE AS A RESULT OF PASSAGE THROUGH A FOURDRINIER MACHINE OR THE LIKE, THE WIRE SIDE OF SAID SHEET BEING THE DOWNSTREAM SIDE DURING FILTRATION AND A DOWNSTREAM LAYER OF APPROXIMATELY ONE-HALF THE THICKNESS OF THE SHEET IMPREGNATED WITH RESIN IN SUFFICIENT QUANTITY TO STIFFEN AND RIGIDIZE THE FIBERS BUT NOT SUBSTANTIALLY REDUCE THE POROSITY OF SAID LAYER AS COMPARED WITH UNIMPREGNATED FIBERS, THE REMAINDER OF THE THICKNESS OF THE SHEET FORMING THE THE UPSTREAM SIDE COMPRISING FIBERS THAT ARE ABSORBENT AND RETAIN ESSENTIALLY THE CHARACTERISTICS OF SID PULP, SAID SHEET HAVING A SUBSTANTIALLY UNIFORM POROSITY THROUGHOUT ITS THICKNESS, THE UPSTREAM LAYER COMPRISING AN ABSORBENT FILTER AND THE DOWNSTREAM LAYER FIXING THE FLOW PATH THROUGH THE SHEET, FURNISHING SUPPORT FOR THE UPSTREAM LAYER, AND PROVIDING A MECHANICAL STRAINER.
Claim 2
Dependent Claim
158 words
A FILTER MATERIAL COMPRISING MONOLITHIC SHEET OF PURIFIED ALPHA CELLULOSE PULP FORMED OF SECOND CUT COTTOM LINTERS FIBERS OF APPROXIMATELY 2 MM. OR LESS AVERAGE LENGTH AND HAVING A WIRE SIDE AS A RESULT OF PASSAGE THROUGH A FOURDRINIER MACHINE OR THE LIKE, THE WIRE SIDE OF SAID SHEET BEING THE DOWNSTREAM SIDE DURING FILTRATION AND A DOWNSTREAM LAYER OF APPROXIMATELY ONE-HALF THE THICKNESS OF THE SHEET IMPREGNATED WITH RESIN IN SUFFICIENT QUANTITY TO STIFFEN AND RIGIDIZE THE FIBERS BUT NOT SUBSTANTIALLY REDUCE THE POROSITY OF SAID LAYER AS COMPARED WITH UNIMPREGNATED FIBERS, THE REMAINDER OF THE THICKNESS OF THE SHEET FORMING THE THE UPSTREAM SIDE COMPRISING FIBERS THAT ARE ABSORBENT AND RETAIN ESSENTIALLY THE CHARACTERISTICS OF SID PULP, SAID SHEET HAVING A SUBSTANTIALLY UNIFORM POROSITY THROUGHOUT ITS THICKNESS, THE UPSTREAM LAYER COMPRISING AN ABSORBENT FILTER AND THE DOWNSTREAM LAYER FIXING THE FLOW PATH THROUGH THE SHEET, FURNISHING SUPPORT FOR THE UPSTREAM LAYER, AND PROVIDING A MECHANICAL STRAINER.
References Cited (Backward Citations)
US437435A
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US2122111A
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GB763782A
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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) | 1966-12-30 | 1967-07-01 | 1967-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-12-30 | 1971-07-01 | 1971-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-12-30 | 1975-07-01 | 1975-12-31 | $7700.00 | Window Closed / Lapsed |