US4420370A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulp agitating device and method having multiple protruding inserts
Assignee: Jwi Ltd
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Filing: 1982-07-19
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Granted: 1983-12-13
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Expires: 2002-07-19
Abstract
Abstract Relatively small easily exchangeable wear resistant inserts are mounted in a plurality of lengthwise grooves in a forming board or foil blade of a paper making machine so that a portion of each insert protrudes above the surface of the blade to form cross-machine direction channels on the blade. The channels promote agitation of the pulp stock on the forming fabric as it passes in contact with the blade.
Inventors
- 👤 Nabil R. Saad
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:21
CPC Classifications
D; D21; D21F; D21F1/00; D21F1/48; D21F1/483; D21F1/009; D21F1/18; D21F1/20
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
114 words
A pulp agitating device comprising a support member having a single upper surface, a plurality of slots in said upper surface, each said slot having retention means for holding a respective one of a plurality of inserts in sliding engagement therein, said inserts being closely spaced and disposed in parallel relationship to one another and extending in a cross-machine direction and protruding above said upper surface to form cross-machine channels therebetween, said support member being supported in contact with a moving endless forming fabric of a paper-making machine to induce micro-pressure pulses to said moving forming fabric whereby fibers are agitated in pulp suspension on said fabric to obtain better distribution of said fibers.
Claim 2
Dependent Claim
114 words
A pulp agitating device comprising a support member having a single upper surface, a plurality of slots in said upper surface, each said slot having retention means for holding a respective one of a plurality of inserts in sliding engagement therein, said inserts being closely spaced and disposed in parallel relationship to one another and extending in a cross-machine direction and protruding above said upper surface to form cross-machine channels therebetween, said support member being supported in contact with a moving endless forming fabric of a paper-making machine to induce micro-pressure pulses to said moving forming fabric whereby fibers are agitated in pulp suspension on said fabric to obtain better distribution of said fibers.
Claim 3
Dependent Claim
19 words
A pulp agitating device as claimed in claim 1 wherein said inserts are removably secured in said upper surface.
Claim 4
Dependent Claim
30 words
A pulp agitating device as claimed in claim 2 wherein said retention means is constituted by a dovetailed slot having opposed side walls to receive an insert of dovetail cross-section.
Claim 5
Dependent Claim
19 words
A pulp agitating device as claimed in claim 2 wherein said inserts have a flat upper fabric support surface.
Claim 6
Dependent Claim
35 words
A pulp agitating device as claimed in claim 4 wherein said flat upper fabric support surface has a downstream portion diverging downwardly backwards at an angle of from 0° to 10° from said support surface.
Claim 7
Dependent Claim
35 words
A pulp agitating device as claimed in claim 4 wherein said flat upper fabric support surface has an upstream portion diverging downwardly frontwards at an angle of from 0° to 10° from said support surface.
Claim 8
Dependent Claim
33 words
A pulp agitating device as claimed in claim 2 wherein said inserts have an upper fabric support surface that has a contoured shape at the protruding portion that is curved in any way.
Claim 9
Dependent Claim
50 words
A pulp agitating device as claimed in claim 2 wherein said inserts are positioned in selected ones of said slots, there being provided filler inserts positioned in remaining ones of said slots, said filler inserts having a top surface in flush alignment with said upper surface of said support member.
Claim 10
Dependent Claim
29 words
A pulp agitating device as claimed in claim 1 wherein said inserts are made of wear-resistant material such as aluminum oxide, tungsten carbide, stainless steel coated with tungsten carbide.
Claim 11
Dependent Claim
35 words
A pulp agitating device as claimed in claim 9 wherein said plurality of inserts are spaced a distance that provides reduced contact area with the said moving endless forming fabric whereby to reduce friction therewith.
Claim 12
Dependent Claim
17 words
A pulp agitating device as claimed in claim 2 wherein said support member is a foil blade.
Claim 13
Dependent Claim
18 words
A pulp agitating device as claimed in claim 2 wherein said support member is a forming board blade.
Claim 14
Dependent Claim
23 words
A pulp agitating device as claimed in claim 2 wherein said support member is a curved forming shoe of a twin wire machine.
Claim 15
Dependent Claim
141 words
In combination with a forming section of a paper-making machine having a moving endless forming fabric on a surface of which is flowed a layer of pulp fibers in pulp suspension from a headbox slice, the improvement comprising a support member having a single upper surface located in contact with the other surface of said fabric, a plurality of slots in said upper surface, each said slot having retention means for holding a respective one of a plurality of inserts in sliding engagement therein, said inserts being closely spaced and disposed in parallel relationship to one another and extending in a cross-machine direction and protruding above said upper surface to form cross-machine channels therebetween to induce micro-pressure pulses to said moving forming fabric whereby fibers are agitated in said pulp suspension on said fabric to obtain better distribution of said fibers.
Claim 16
Dependent Claim
141 words
In combination with a forming section of a paper-making machine having a moving endless forming fabric on a surface of which is flowed a layer of pulp fibers in pulp suspension from a headbox slice, the improvement comprising a support member having a single upper surface located in contact with the other surface of said fabric, a plurality of slots in said upper surface, each said slot having retention means for holding a respective one of a plurality of inserts in sliding engagement therein, said inserts being closely spaced and disposed in parallel relationship to one another and extending in a cross-machine direction and protruding above said upper surface to form cross-machine channels therebetween to induce micro-pressure pulses to said moving forming fabric whereby fibers are agitated in said pulp suspension on said fabric to obtain better distribution of said fibers.
Claim 17
Independent Claim
139 words
A method of agitating fibers in a pulp suspension in a moving endless forming fabric of a paper-making machine, said method comprising the steps of positioning a support element having a single upper surface having formed therein a plurality of slots provided with retention means for holding a respective one of a plurality of inserts in sliding engagement therein, positioning said inserts in said slots in closely spaced parallel relationship to one another and extending in a cross-machine direction and protruding above said upper surface to form cross-machine channels therebetween, displacing a surface of said forming fabric in contact with said inserts while supporting on an opposite surface said pulp suspension; inducing, by means of said channels, micro-pressure pulses to said moving forming fabric whereby fibers are agitated in said pulp suspension to obtain better distribution of said fibers.
Claim 18
Independent Claim
139 words
A method of agitating fibers in a pulp suspension in a moving endless forming fabric of a paper-making machine, said method comprising the steps of positioning a support element having a single upper surface having formed therein a plurality of slots provided with retention means for holding a respective one of a plurality of inserts in sliding engagement therein, positioning said inserts in said slots in closely spaced parallel relationship to one another and extending in a cross-machine direction and protruding above said upper surface to form cross-machine channels therebetween, displacing a surface of said forming fabric in contact with said inserts while supporting on an opposite surface said pulp suspension; inducing, by means of said channels, micro-pressure pulses to said moving forming fabric whereby fibers are agitated in said pulp suspension to obtain better distribution of said fibers.
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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) | 1986-12-12 | 1987-06-13 | 1987-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-12 | 1991-06-13 | 1991-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-12 | 1995-06-13 | 1995-12-13 | $7700.00 | Window Closed / Lapsed |