US3853695A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Entraining a liquid into a fiber slurry to accelerate it prior to discharge from a flow path onto a forming wire
Assignee: Individual
•
Filing: 1974-01-28
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Granted: 1974-12-10
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Expires: 1994-01-28
Abstract
Abstract A slurry mixture of fibrous material and fluid is introduced into a predetermined flow path which leads to an exit aperture. A restricted opening preferably in the form of a slit is provided which communicates with the flow path at a predetermined location upstream from said exit aperture. An entraining fluid, such as clear or white water, is introduced through the slit and into the flow path whereupon the entraining fluid, due to a ''''Coanda effect,'''' attaches itself to a convexly-curved flow attachment surface positioned adjacent to said slit whereby said entraining fluid flows along said flow path in a direction toward said exit aperture at a velocity substantially greater than the flow velocity of the slurry upstream from the slit. The entraining fluid accelerates the slurry and causes same to exit from the exit aperture at a high rate of speed to the forming surface of a web-forming machine positioned adjacent to the exit aperture.
Inventors
- 👤 I Reba
- 👤 D Wilhoit
- 👤 S Back
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:58
CPC Classifications
D; D21; D21F; D21F1/00; D21F1/02; D21F1/022; D21F1/028; D21F1/06
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
152 words
Apparatus for delivering a fiber slurry to the forming surface of a sheet- or web-forming machine, including: means defining a flow path for said slurry and leading to an elongate exit aperture; means defining at least one elongate, narrow slit communicating with said flow path and extending substantially parallel to said exit aperture closely adjacent thereto; means for introducing an entraining fluid through said slit and into said flow path at a velocity substantially greater than the flow velocity of said slurry immediately upstream from said slit; and a convex, generally curved fluid-flow attachment surface leading from said slit toward said exit aperture to which the entraining fluid attaches iTself due to the Coanda effect and exerts a substantial pulling force on said slurry to entrain and accelerate said slurry toward said exit aperture while mixing with said slurry, and provide a high percentage of all energy required to accelerate said slurry.
Claim 2
Dependent Claim
152 words
Apparatus for delivering a fiber slurry to the forming surface of a sheet- or web-forming machine, including: means defining a flow path for said slurry and leading to an elongate exit aperture; means defining at least one elongate, narrow slit communicating with said flow path and extending substantially parallel to said exit aperture closely adjacent thereto; means for introducing an entraining fluid through said slit and into said flow path at a velocity substantially greater than the flow velocity of said slurry immediately upstream from said slit; and a convex, generally curved fluid-flow attachment surface leading from said slit toward said exit aperture to which the entraining fluid attaches iTself due to the Coanda effect and exerts a substantial pulling force on said slurry to entrain and accelerate said slurry toward said exit aperture while mixing with said slurry, and provide a high percentage of all energy required to accelerate said slurry.
Claim 3
Dependent Claim
18 words
The apparatus according to claim 1 wherein said slit is disposed substantially perpendicularly to said slurry flow path.
Claim 4
Dependent Claim
22 words
The apparatus according to claim 1 including means for selectively varying the location of said slit relative to said flow attachment surface.
Claim 5
Dependent Claim
23 words
The apparatus according to claim 1 including means for selectively varying the angular disposition of said slit relative to said slurry flow path.
Claim 6
Dependent Claim
30 words
The apparatus according to claim 1 wherein said flow-path defining means includes a pair of spaced-apart lips for directing said entraining fluid and the entrained slurry to said forming surface.
Claim 7
Dependent Claim
20 words
The apparatus according to claim 5 wherein said fluid-flow attachment surface is formed on at least one of said lips.
Claim 8
Dependent Claim
18 words
The apparatus according to claim 5 additionally including means for adjustably moving said lips relative to one another.
Claim 9
Dependent Claim
19 words
The apparatus according to claim 5 wherein at least one of said lips is constructed of a flexible material.
Claim 10
Dependent Claim
31 words
The apparatus according to claim 5 wherein one of said lips extends inwardly from said exit aperture a sufficient distance such that a portion thereof is juxtaposed relative to said slit.
Claim 11
Dependent Claim
44 words
The apparatus according to claim 1 wherein said entraining fluid introduction means is adapted to introduce said entraining fluid into said flow path at a flow velocity equal to at least ten times the flow velocity of the slurry immediately upstream from said slit.
Claim 12
Dependent Claim
48 words
The apparatus according to claim 1 wherein said entraining fluid introduction means is adapted to introduce said entraining fluid into said flow path at a kinetic energy level of at least fifty times the magnitude of the kinetic energy level of the slurry immediately upstream from said slit.
Claim 13
Dependent Claim
16 words
The apparatus according to claim 1 additionally including means for adjusting the size of said slit.
Claim 14
Dependent Claim
63 words
The apparatus according to claim 1 wherein a plurality of slits communicate with said flow path and said means for introducing said entraining fluid into said flow path includes means for forcing entraining fluid through each slit and a fluid-flow attachment surface leading from each slit, each said fluid-flow attachment surface being positioned to direct the fluid attached thereto in a downstream direction.
Claim 15
Dependent Claim
24 words
The apparatus according to claim 13 additionally including separator means disposed in said flow path between at least some of said fluid-flow attachment surfaces.
Claim 16
Dependent Claim
20 words
The apparatus according to claim 1 wherein said means defining a flow path for said slurry includes a headbox chamber.
Claim 17
Dependent Claim
29 words
The apparatus according to claim 15 wherein baffle means is disposed in said headbox chamber for the purpose of smoothing the flow of said slurry along said flow path.
Claim 18
Dependent Claim
34 words
The apparatus according to claim 1 wherein the ratio of the radius of curvature of said surface at the slit location to the width of said slit in the range from 2.5 to 150.
Claim 19
Independent Claim
162 words
A method for delivering a fiber slurry to the forming surface of a sheet- or web-forming machine, comprising the steps of: introducing a slurry mixture into a predetermined flow path; injecting a fluid under pressure through an elongated slit disposed substantially perpendicular to said flow path into said flow path at a predetermined location upstream of said forming surface and at a velocity substantially greater than the velocity of the slurry mixture immediately upstream from said location; attaching the injected fluid due to the Coanda effect to a convex, generally curved fluid-flow attachment surface leading in a downstream direction from said predetermined injection location whereby the injected fluid exerts a substantial pulling force on said slurry and entrains and accelerates tHe flow of the slurry along said predetermined flow path, and provides a high percentage of all energy required to accelerate said slurry; mixing the injected fluid and the slurry; and directing the mixed fluid and entrained slurry onto the forming surface.
Claim 20
Independent Claim
162 words
A method for delivering a fiber slurry to the forming surface of a sheet- or web-forming machine, comprising the steps of: introducing a slurry mixture into a predetermined flow path; injecting a fluid under pressure through an elongated slit disposed substantially perpendicular to said flow path into said flow path at a predetermined location upstream of said forming surface and at a velocity substantially greater than the velocity of the slurry mixture immediately upstream from said location; attaching the injected fluid due to the Coanda effect to a convex, generally curved fluid-flow attachment surface leading in a downstream direction from said predetermined injection location whereby the injected fluid exerts a substantial pulling force on said slurry and entrains and accelerates tHe flow of the slurry along said predetermined flow path, and provides a high percentage of all energy required to accelerate said slurry; mixing the injected fluid and the slurry; and directing the mixed fluid and entrained slurry onto the forming surface.
Claim 21
Dependent Claim
34 words
The method according to claim 18 wherein the step of entraining said slurry is accomplished by creating a zone of reduced pressure in said flow path in the vicinity of said fluid-flow attachment surface.
Claim 22
Dependent Claim
12 words
The method according to claim 18 wherein said injected fluid is water.
Claim 23
Dependent Claim
38 words
The method according to claim 18 wherein said fluid is injected into said predetermined flow path at a flow velocity equal to at least ten times the flow velocity of the slurry immediately upstream of said predetermined location.
Claim 24
Dependent Claim
41 words
The method according to claim 18 wherein said fluid is injected into said predetermined flow path at a kinetic energy level of at least fifty times the magnitude of the kinetic energy level of the slurry immediately upstream from said slit.
Claim 25
Dependent Claim
154 words
In combination: means defining a forming surface; and means for delivering a slurry to said forming surface comprising: a. means defining a predetermined flow path for said slurry leading to an elongate exit aperture through which said slurry is adapted to discharge into engagement with said forming surface; b. means defining at least one elongate restricted opening communicating with said flow path closely adjacent to said exit aperture and in substantially parallel relationship thereto; c. a convex, generally curved fluid-flow attachment surface leading from said restricted opening toward said exit aperture; and d. means for introducing an entraining fluid under pressure into said flow path through said restricted opening whereby said fluid attaches itself to said fluid-flow attachment surface due to the Coanda effect to exert a substantial pulling force on said slurry and direct said slurry toward said exit aperture and provide a high percentage of all energy required to accelerate said slurry.
Claim 26
Dependent Claim
154 words
In combination: means defining a forming surface; and means for delivering a slurry to said forming surface comprising: a. means defining a predetermined flow path for said slurry leading to an elongate exit aperture through which said slurry is adapted to discharge into engagement with said forming surface; b. means defining at least one elongate restricted opening communicating with said flow path closely adjacent to said exit aperture and in substantially parallel relationship thereto; c. a convex, generally curved fluid-flow attachment surface leading from said restricted opening toward said exit aperture; and d. means for introducing an entraining fluid under pressure into said flow path through said restricted opening whereby said fluid attaches itself to said fluid-flow attachment surface due to the Coanda effect to exert a substantial pulling force on said slurry and direct said slurry toward said exit aperture and provide a high percentage of all energy required to accelerate said slurry.
Claim 27
Independent Claim
133 words
A METHOD FOR DELIVERING A SLURRY TO THE FORMING SURFACE OF A SHEET- OR WEB-FORMING MACHINE, COMPRISING THE STEPS OF: INTRODUCTING A SLURRY MIXTURE INTO A PREDETERMINED FLOW PATH LEADING TOWARD EXIT APERTURE DISPOSED ADJACENT TO SAID FORMING SURFACE; INTRODUCING AN ENTRAINING FLUID INTO SAID FLOW PATH UNDER PRESSURE IN THE FORM OF A THIN, ELONGATED STREAM; AND DURECTING THE FLOW OF SAID FLUID TOWARD SAID EXIT APERTURE BY ATTACHING SAID THIN, ELONGATED STREAM OF FLUID DUE TO THE COANDA EFFECT TO A CONVEX, GENERALLY CURVED FLUID-FLOW ATTACHMENT SURFACE LEADING FROM THE LOCATION OF INTRODUCTION OF SAID SLURRY TOWARD SAID EXIT APERTURE WHEREBY SAID SLURRY IS PULLED TOWARD SAID EXIT APERTURE BY A SUBSTANTIAL PULLING FORCE EXERTED BY SAID FLUID TO RPOVIDE A HIGH PERCENTAGE OF ALL ENERGY REQUIRED TO ACCELERATE SAID SLURRY.
Claim 28
Independent Claim
133 words
A METHOD FOR DELIVERING A SLURRY TO THE FORMING SURFACE OF A SHEET- OR WEB-FORMING MACHINE, COMPRISING THE STEPS OF: INTRODUCTING A SLURRY MIXTURE INTO A PREDETERMINED FLOW PATH LEADING TOWARD EXIT APERTURE DISPOSED ADJACENT TO SAID FORMING SURFACE; INTRODUCING AN ENTRAINING FLUID INTO SAID FLOW PATH UNDER PRESSURE IN THE FORM OF A THIN, ELONGATED STREAM; AND DURECTING THE FLOW OF SAID FLUID TOWARD SAID EXIT APERTURE BY ATTACHING SAID THIN, ELONGATED STREAM OF FLUID DUE TO THE COANDA EFFECT TO A CONVEX, GENERALLY CURVED FLUID-FLOW ATTACHMENT SURFACE LEADING FROM THE LOCATION OF INTRODUCTION OF SAID SLURRY TOWARD SAID EXIT APERTURE WHEREBY SAID SLURRY IS PULLED TOWARD SAID EXIT APERTURE BY A SUBSTANTIAL PULLING FORCE EXERTED BY SAID FLUID TO RPOVIDE A HIGH PERCENTAGE OF ALL ENERGY REQUIRED TO ACCELERATE SAID SLURRY.
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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) | 1977-12-09 | 1978-06-10 | 1978-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-09 | 1982-06-10 | 1982-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-09 | 1986-06-10 | 1986-12-10 | $7700.00 | Window Closed / Lapsed |