US2734631A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Grading process and apparatus
Assignee: —
•
Filing: —
•
Granted: 1956-02-14
•
Expires: 1973-02-14
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:03
CPC Classifications
G; G01; G01N; G01N15/00; G01N15/02; G01N15/0272
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
190 words
A METHOD OF SCREEN TESTING FOR PARTICLE SIZE ANALYSIS WHEREBY THE PERCENTAGE OF PARTICLES IN A GIVEN SAMPLE OF LARGER THAN A SPECIFIED SIZE IS DETERMINED COMPRISING: WEIGHING A SAMPLE OF THE MATERIAL TO BE TESTED, PASTING SAID SAMPLE WITH A WETTING AGENT IN AN AQUEOUS PHASE TO FORM THEREBY A UNIFORM DISPERSION OF THE SAMPLE AS A SLURRY, CHANGING SAID WEIGHED SAMPLE TO A ROTATABLE CYLINDRICAL DRUM HAVING A HORIZONTAL SCREEN AT THE BOTTOM THEREOF AND CONTIGUOUS UPSTANDING SIDES FORMING A SIEVE, ROTATING SAID SIEVE AT A PREDETERMINED RATE, DIRECTING A SHEET OF LIQUID AT A PREDETERMINED RATE OF FLOW AND PRESSURE AND FOR A PREDETERMINED TIME AGAINST THE SCREEN AT AN ANGLE OF FROM 30* TO 90* FROM THE HORIZONTAL TO WASH THE SMALLER PARTICLES THROUGH THE SCREEN, WHEREBY THE SAMPLE PARTICLES ARE CLASSIFIED ACCORDING TO SIZE, THE VELOCITY OF THE SHEET OF LIQUID AND THE RATE OF ROTATION OF THE CYLINDER BEING INSUFFICIENT TO CAUSE ANY APPRECIABLE ATTRITION OF THE SAMPLE PARTICLES N THE SCREEN, DRYING THE RESIDUE ON THE SCREEN, WEIGHING SAID RESIDUE, AND CALCULATING THE PERCENTAGE OF SAID RESIDUE BASED ON THE ORIGINAL SAMPLE WEIGHT.
Claim 2
Independent Claim
190 words
A METHOD OF SCREEN TESTING FOR PARTICLE SIZE ANALYSIS WHEREBY THE PERCENTAGE OF PARTICLES IN A GIVEN SAMPLE OF LARGER THAN A SPECIFIED SIZE IS DETERMINED COMPRISING: WEIGHING A SAMPLE OF THE MATERIAL TO BE TESTED, PASTING SAID SAMPLE WITH A WETTING AGENT IN AN AQUEOUS PHASE TO FORM THEREBY A UNIFORM DISPERSION OF THE SAMPLE AS A SLURRY, CHANGING SAID WEIGHED SAMPLE TO A ROTATABLE CYLINDRICAL DRUM HAVING A HORIZONTAL SCREEN AT THE BOTTOM THEREOF AND CONTIGUOUS UPSTANDING SIDES FORMING A SIEVE, ROTATING SAID SIEVE AT A PREDETERMINED RATE, DIRECTING A SHEET OF LIQUID AT A PREDETERMINED RATE OF FLOW AND PRESSURE AND FOR A PREDETERMINED TIME AGAINST THE SCREEN AT AN ANGLE OF FROM 30* TO 90* FROM THE HORIZONTAL TO WASH THE SMALLER PARTICLES THROUGH THE SCREEN, WHEREBY THE SAMPLE PARTICLES ARE CLASSIFIED ACCORDING TO SIZE, THE VELOCITY OF THE SHEET OF LIQUID AND THE RATE OF ROTATION OF THE CYLINDER BEING INSUFFICIENT TO CAUSE ANY APPRECIABLE ATTRITION OF THE SAMPLE PARTICLES N THE SCREEN, DRYING THE RESIDUE ON THE SCREEN, WEIGHING SAID RESIDUE, AND CALCULATING THE PERCENTAGE OF SAID RESIDUE BASED ON THE ORIGINAL SAMPLE WEIGHT.
References Cited (Backward Citations)
US1041935A
Cited
US2164052A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-02-13 | 1959-08-15 | 1960-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-02-13 | 1963-08-15 | 1964-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-02-13 | 1967-08-15 | 1968-02-14 | $7700.00 | Window Closed / Lapsed |