Patent US4376042A successfully refreshed from Google Patents.
US4376042A
Expired / Lapsed
US
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Chip sizing process
Assignee: Weyerhaeuser Co
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Filing: 1981-05-11
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Granted: 1983-03-08
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Expires: 2001-05-11
Abstract
Abstract A chip screening system has a primary screening station for dividing an incoming flow of chips into a first acceptable fraction and a second fraction having acceptable chips and also both oversized and overthick chips. The second fraction is directed to a second screening station where the incoming flow will again be fractionated into an acceptable flow being screened primarily according to thickness and a second fraction being composed of oversized and overthick chips. The second fraction is then directed to a size reducing station.
Inventors
- 👤 Robert A. Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:20
CPC Classifications
B; B07; B07B; B07B9/00; D; D21; D21B; D21B1/00; D21B1/02; D21B1/023
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
167 words
A process for fractionating and sizing a flow of incoming wood chips from a known source into an output flow of chips falling in a predetermined size range with substantially all of the chips in the output flow having a thickness falling within a predetermined thickness range, comprising the steps of: directing the incoming flow to a primary screening station where at least two fractions are generated with a first fraction containing chips falling substantially within the predetermined acceptable size and thickness range and a second fraction comprising at least 30% by weight of the incoming flow having a substantial majority of the oversize and overthick chips together with a substantial amount of chips falling within the acceptable size and thickness range, and directing the second fraction to a second screening station where at least two fractions are generated with a fourth fraction containing chips falling substantially within the predetermined acceptable size and thickness range and a fifth fraction containing chips substantially all of which are overthick.
Claim 2
Dependent Claim
167 words
A process for fractionating and sizing a flow of incoming wood chips from a known source into an output flow of chips falling in a predetermined size range with substantially all of the chips in the output flow having a thickness falling within a predetermined thickness range, comprising the steps of: directing the incoming flow to a primary screening station where at least two fractions are generated with a first fraction containing chips falling substantially within the predetermined acceptable size and thickness range and a second fraction comprising at least 30% by weight of the incoming flow having a substantial majority of the oversize and overthick chips together with a substantial amount of chips falling within the acceptable size and thickness range, and directing the second fraction to a second screening station where at least two fractions are generated with a fourth fraction containing chips falling substantially within the predetermined acceptable size and thickness range and a fifth fraction containing chips substantially all of which are overthick.
Claim 3
Dependent Claim
20 words
The process as in claim 1 further including the step of directing the fifth fraction to a size reducing means.
Claim 4
Dependent Claim
25 words
The process as in claim 2 in which the size reducing means is a chip slicer generating chips falling substantially within the acceptable thickness range.
Claim 5
Dependent Claim
37 words
The process as in claim 2 further including the step of directing the fifth fraction past a metal removal means in order to remove metal elements prior to directing the fifth flow to the size reducing means.
Claim 6
Dependent Claim
34 words
The process as in claim 2 further including the step of directing the output flow from the size reducing means back to the primary screening station where it is merged into the incoming flow.
Claim 7
Dependent Claim
24 words
The process as in claim 2 including the step of collecting all fractions containing chips falling within the predetermined acceptable size and thickness range.
Claim 8
Dependent Claim
25 words
The process as in claim 1 in which a third fraction is generated containing chips falling substantially in a size range below the acceptable range.
Claim 9
Dependent Claim
16 words
The process as in claim 1 in which the primary screening station is a gyratory screen.
Claim 10
Dependent Claim
16 words
The process as in claim 1 in which the second screening station is a disc screen.
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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) | 1986-03-07 | 1986-09-06 | 1987-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-07 | 1990-09-06 | 1991-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-07 | 1994-09-06 | 1995-03-08 | $7700.00 | Window Closed / Lapsed |