Patent US3756406A successfully refreshed from Google Patents.
US3756406A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Grain cleaner
Assignee: United States Department of Agriculture
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Filing: 1971-07-14
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Granted: 1973-09-04
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Expires: 1991-07-14
Abstract
Abstract The grain cleaner comprises a pair of rotating concentric, coaxial screens. Grain is delivered to the inner screen which has a mesh large enough to pass the grain and light impurities, such as chaff, but too small to pass large, heavy impurities such as straw. Baffles move the retained straw toward an exit at one end of the inner cyclinder for collection and disposal. A current of air blowing in the space between the two cylinders separates the grain from the chaff and dust and carries the latter to an exit. Baffles in the outer cylinder move the cleaned grain in a direction opposite to the flow of air for discharge and collection.
Inventors
- 👤 A Khan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:37
CPC Classifications
B; B07; B07B; B07B1/00; B07B1/18; B07B1/22; B07B1/24
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
144 words
A grain cleaning machine comprising an inner cylinder adapted for rotation about a longitudinal axis, said inner cylinder having openings therethrough closely spaced from each other substantially throughout its area, said opening being of such size as to pass the kernels of grain, dirt and smaller-than-grain impurities and to retain straws and larger-than-grain impurities; an outer cylinder surrounding said inner cylinder; the outer periphery of said inner cylinder and the inner periphery of said outer cylinder defining an annular space; means providing grain inlet into said inner cylinder; means to provide air inlet into said annular space; means to tumble the grain in said annular space; means providing a grain outlet on said outer cylinder; guide means in said outer cylinder to advance grains toward said outlet and drive means to operate said cylinders and said means providing air inlet into said annular space.
Claim 2
Dependent Claim
144 words
A grain cleaning machine comprising an inner cylinder adapted for rotation about a longitudinal axis, said inner cylinder having openings therethrough closely spaced from each other substantially throughout its area, said opening being of such size as to pass the kernels of grain, dirt and smaller-than-grain impurities and to retain straws and larger-than-grain impurities; an outer cylinder surrounding said inner cylinder; the outer periphery of said inner cylinder and the inner periphery of said outer cylinder defining an annular space; means providing grain inlet into said inner cylinder; means to provide air inlet into said annular space; means to tumble the grain in said annular space; means providing a grain outlet on said outer cylinder; guide means in said outer cylinder to advance grains toward said outlet and drive means to operate said cylinders and said means providing air inlet into said annular space.
Claim 3
Dependent Claim
36 words
A grain cleaning machine as in claim 1 wherein the inner cylinder has a plurality of spiral baffles inside said inner cylinder to form an internal auger to advance straws and larger-than-grain impurities towards an outlet.
Claim 4
Dependent Claim
43 words
A grain cleaning machine as in claim 2 wherein the outer cylinder openings therethrough closely spaced from each other substantially throughout its area, said openings being of such size as to pass dirt, sand and smaller-than-grain impurities and to retain kernels of grains.
Claim 5
Dependent Claim
36 words
A grain cleaning machine as in claim 3 wherein the outer cylinder has a plurality of projections, said projections being constructed and arranged to provide turning and tumbling of grains upon rotation of said outer cylinder.
Claim 6
Dependent Claim
65 words
A grain cleaning machine as in claim 4 wherein the guide means in the outer cylinder comprise a plurality of slide fins disposed spirally inside the outer cylinder to move the grain towards the grain outlet in axial direction counter to the flow of air in said annular space as the grains come into engagement with said slide fins when said outer cylinder is rotated.
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) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |