US4700900A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two stage refiner
Assignee: Kvaerner Hymac Inc
•
Filing: 1985-12-17
•
Granted: 1987-10-20
•
Expires: 2005-12-17
Abstract
Abstract A paper pulp refiner for refining high consistency stock characterized by two virtually identical refining zones connected in series which have an interstage device to remove excess steam and whose axial loads can be varied independently thus producing two stage pump from a single refiner.
Inventors
- 👤 Stephen A. Rowland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:43
CPC Classifications
D; D21; D21D; D21D1/00; D21D1/20; D21D1/30; D21D1/303
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
247 words
A refiner for the two-stage production of pulp from unrefined material comprising wood chips comprises of: (a) a single housing having two refining zones; (b) a rotor fixedly mounted on a rotatable shaft for rotation therewith, said rotor positioned between opposing supported ends of said shaft and including opposing grinding surfaces; (c) a first stator in opposing relation to one grinding surface of said rotor in a first refining zone and a second stator in opposing relation to the opposing grinding surface of said rotor in a second refining zone; (d) means to measure the relative power consumption in each refining zone associated with the grinding of material which occurs by cooperation of said stators and said rotor in each refining zone; (e) means to independently advance or retract said first and second stators either toward or away from said opposing grinding surfaces to vary both the clearance between said stators and said rotor and the axial load in each refining zone to maintain a desired power consumption in each refining zone; (f) conveyor means to feed unrefined wood chips between said first stator and said rotor whereby gaseous by-products are produced and said wood chips are partially refined; (g) separation means to separate said gaseous by-products from said partially refined wood chips; and (h) conveyor means to feed said partially refined wood chips subsequent to separation of said gaseous by-products between said second stator and said rotor whereby said partially refined wood chips are further refined.
Claim 2
Dependent Claim
247 words
A refiner for the two-stage production of pulp from unrefined material comprising wood chips comprises of: (a) a single housing having two refining zones; (b) a rotor fixedly mounted on a rotatable shaft for rotation therewith, said rotor positioned between opposing supported ends of said shaft and including opposing grinding surfaces; (c) a first stator in opposing relation to one grinding surface of said rotor in a first refining zone and a second stator in opposing relation to the opposing grinding surface of said rotor in a second refining zone; (d) means to measure the relative power consumption in each refining zone associated with the grinding of material which occurs by cooperation of said stators and said rotor in each refining zone; (e) means to independently advance or retract said first and second stators either toward or away from said opposing grinding surfaces to vary both the clearance between said stators and said rotor and the axial load in each refining zone to maintain a desired power consumption in each refining zone; (f) conveyor means to feed unrefined wood chips between said first stator and said rotor whereby gaseous by-products are produced and said wood chips are partially refined; (g) separation means to separate said gaseous by-products from said partially refined wood chips; and (h) conveyor means to feed said partially refined wood chips subsequent to separation of said gaseous by-products between said second stator and said rotor whereby said partially refined wood chips are further refined.
Claim 3
Dependent Claim
13 words
The apparatus of claim 1 wherein said separation means comprises a cyclone separator.
Claim 4
Dependent Claim
16 words
The apparatus of claim 1 wherein said means to measure power consumption comprises torque measuring means.
Claim 5
Dependent Claim
13 words
The apparatus of claim 1 wherein said conveyor means comprises a screw conveyor.
Claim 6
Dependent Claim
264 words
A refiner for the two-stage production of pulp from unrefined material comprising wood chips comprised of: (a) a single housing having two refined zones; (b) first and second rotors fixedly mounted on a rotatable shaft for rotation therewith, said rotors being spaced axially from each other in first and second refining zones, respectively, with each rotor positioned between opposing supported ends of said shaft and including grinding surfaces on one surface thereof; (c) a first stator in opposing relation to said grinding surface of said first rotor in said first refining zone and a second stator in opposing relation to said grinding surface of said second rotor in said second refining zone; (d) means to measure the relative power consumption in each refining zone associated with the grinding of material which occurs by cooperation of said stators and said rotor in each refining zone; (e) means to independently advance or retract said first and second stators either toward or away from said opposing grinding surfaces of said rotors to vary both the clearance between said stators and said rotors and the axial load in each refining zone; (f) conveyor means to feed unrefined wook chips between said first stator and siad first rotor whereby gaseous by-products are produced and said wood chips are partially refined. (g) separation means to separate said gaseous by-products from said partially refined wood chips; and (h) conveyor means to feed said partially refined wood chips subsequent to separation of said gaseous by-products between said second stator and said second rotor whereby said partially refined wood chips are further refined.
Claim 7
Dependent Claim
264 words
A refiner for the two-stage production of pulp from unrefined material comprising wood chips comprised of: (a) a single housing having two refined zones; (b) first and second rotors fixedly mounted on a rotatable shaft for rotation therewith, said rotors being spaced axially from each other in first and second refining zones, respectively, with each rotor positioned between opposing supported ends of said shaft and including grinding surfaces on one surface thereof; (c) a first stator in opposing relation to said grinding surface of said first rotor in said first refining zone and a second stator in opposing relation to said grinding surface of said second rotor in said second refining zone; (d) means to measure the relative power consumption in each refining zone associated with the grinding of material which occurs by cooperation of said stators and said rotor in each refining zone; (e) means to independently advance or retract said first and second stators either toward or away from said opposing grinding surfaces of said rotors to vary both the clearance between said stators and said rotors and the axial load in each refining zone; (f) conveyor means to feed unrefined wook chips between said first stator and siad first rotor whereby gaseous by-products are produced and said wood chips are partially refined. (g) separation means to separate said gaseous by-products from said partially refined wood chips; and (h) conveyor means to feed said partially refined wood chips subsequent to separation of said gaseous by-products between said second stator and said second rotor whereby said partially refined wood chips are further refined.
Claim 8
Dependent Claim
13 words
The apparatus of claim 5 wherein said separation means comprises a cyclone separator.
Claim 9
Dependent Claim
16 words
The apparatus of claim 5 wherein said means to measure power consumption comprises torque measuring means.
Claim 10
Dependent Claim
13 words
The apparatus of claim 5 wherein said conveyor means comprises a screw conveyor.
References Cited (Backward Citations)
US608085A
Cited
CA317355A
Cited
CA394296A
Cited
CA783928A
Cited
FR1093443A
Cited
US2864562A
Cited
US3323731A
Cited
US3654075A
Cited
SU562426A1
Cited
SE433365B
Cited
US4457804A
Cited
SE413601B
Cited
US4235665A
Cited
SU644894A1
Cited
US4357208A
Cited
US4298425A
Cited
US4247362A
Cited
CA1125077A
Cited
US4455195A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-10-19 | 1991-04-20 | 1991-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-19 | 1995-04-20 | 1995-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-19 | 1999-04-20 | 1999-10-20 | $7700.00 | Window Closed / Lapsed |