← Back to Patent Explorer
US4099296A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for forming a material web

Assignee: Svenska Flaktfabriken AB
•
Filing: 1976-09-21
•
Granted: 1978-07-11
•
Expires: 1996-09-21
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A web is formed from particulate material, for example wood fibres, by depositing the fibres on a movable deposition surface in a chamber. The particulate material is carried to the surface in an air stream to form a composite material flow which is caused to oscillate across the surface by impulses from separate control means preferably disposed on opposite sides of the stream. The control means is preferably opposed control flows which are caused to vary alternatingly between a minimum and a maximum impulse by use of one or more fluidistors. The fluidistors may be controlled by self-oscillation or by measuring the evenness of the particulate material deposited on the deposition surface. The control may also be effected by adjusting the walls of the chamber to utilize the coanda-effect. The particulate material may be admixed with additives from the control flow and may be charged electrostatically.

Inventors

  • 👤 Lennart Gustavsson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 06:23
CPC Classifications
D; D04; D04H; D04H1/00; D04H1/70; D04H1/72; D04H1/732; D04H1/736

Claims Analysis

Total Claims: 43
Claim 1
Independent Claim 132 words
A method of forming a material web comprising the steps of causing a composite flow of particulate material in a gaseous transport medium flow into a distribution chamber, precipitating said material from said composite flow on a deposition surface in the distribution chamber, exposing the composite material flow to control flows of gaseous medium directed from opposite sides of the flow against the same, and alternatingly varying the size of the impulse of the control flows with a frequency in the range of 1 to 50 c.p.s., each control flow consisting of a plurality of jets, where the impulse of selected jets being varied separately from one another, the variations in said selected jets being out of phase, whereby the composite material flow is distributed across the width of the deposition surface.
Claim 2
Independent Claim 132 words
A method of forming a material web comprising the steps of causing a composite flow of particulate material in a gaseous transport medium flow into a distribution chamber, precipitating said material from said composite flow on a deposition surface in the distribution chamber, exposing the composite material flow to control flows of gaseous medium directed from opposite sides of the flow against the same, and alternatingly varying the size of the impulse of the control flows with a frequency in the range of 1 to 50 c.p.s., each control flow consisting of a plurality of jets, where the impulse of selected jets being varied separately from one another, the variations in said selected jets being out of phase, whereby the composite material flow is distributed across the width of the deposition surface.
Claim 3
Dependent Claim 28 words
A method according to claim 1, characterized in that one control flow assumes its maximum value when the opposed control flow assumes its minimum value, and vice versa.
Claim 4
Dependent Claim 23 words
A method according to claim 1, characterized in that the impulse of the control flow is varied between zero and a maximum value.
Claim 5
Dependent Claim 43 words
A method according to claim 1, characterized in that each control flow consists of jets having a constant basic flow and jets having a variable flow, so that the impulse is varied between the impulse of said basic flow and a maximum value.
Claim 6
Dependent Claim 15 words
A method according to claim 1 wherein the range is between 2 and 20 c.p.s.
Claim 7
Dependent Claim 15 words
A method according to claim 1 wherein the range is between 5 and 15 c.p.s.
Claim 8
Dependent Claim 19 words
A method according to claim 1 characterized in that said jets are opposed and are directed past each other.
Claim 9
Dependent Claim 33 words
A method according to claim 1, characterized in that the control flow is adjusted with respect to both its volume and its direction to control the precipitation of material on the deposition surface.
Claim 10
Dependent Claim 25 words
A method according to claim 1, characterized in that the impulse of the control flow is varied between maximum and minimum values by fluidistor means.
Claim 11
Dependent Claim 22 words
A method according to claim 9, characterized in that the variation is cyclic and is obtained by self-oscillation of the fluidistor means.
Claim 12
Dependent Claim 27 words
A method according to claim 1, including the step of supplying a controlled amount of additives to the control flow for admixing in the composite material flow.
Claim 13
Dependent Claim 44 words
A method according to claim 1 where the particulate material consists of longitudinal particles or fibres, including the step of orienting the direction of the particles during the spreading and precipitation process in the distribution chamber by exposing the material to an electrostatic field.
Claim 14
Dependent Claim 26 words
A method according to claim 1 including the step of moving said deposition surface longitudinally through said chamber as the material is distributed across its width.
Claim 15
Independent Claim 137 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of aperture means forming impulse jets directed against the composite material flow, a variable-pressure gas source for selected aperture means having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber, and a constant-pressure gas source for other aperture means.
Claim 16
Independent Claim 137 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of aperture means forming impulse jets directed against the composite material flow, a variable-pressure gas source for selected aperture means having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber, and a constant-pressure gas source for other aperture means.
Claim 17
Dependent Claim 18 words
An apparatus according to claim 14, characterized in that the aperture means consist of holes disposed in rows.
Claim 18
Dependent Claim 14 words
An apparatus according to claim 14, characterized in that the aperture means are slots.
Claim 19
Dependent Claim 27 words
An apparatus according to claim 14, characterized in that the aperture means of the blowing box are directed in a plane in parallel with the deposition surface.
Claim 20
Dependent Claim 26 words
An apparatus according to claim 14, characterized in that the aperture means of the blowing box are directed in a plane oblique to the deposition surface.
Claim 21
Dependent Claim 21 words
An apparatus according to claim 14, characterized in that the supply members are disposed at different heights above the deposition surface.
Claim 22
Dependent Claim 40 words
An apparatus according to claim 14, characterized in that the supply member comprises blowing boxes disposed opposite each other on different sides of the composite material flow path, the aperture means of said boxes being offset relative to each other.
Claim 23
Dependent Claim 24 words
An apparatus according to the claim 14, characterized in that the means effecting said variable impulse of the control flow consist of fluidistor means.
Claim 24
Dependent Claim 24 words
An apparatus according to the claim 14, characterized in that the means effecting said variable impulse of the control flow consist of valve means.
Claim 25
Dependent Claim 19 words
An apparatus according to the claim 14, characterized in that the deposition surface consists of a movable conveying means.
Claim 26
Dependent Claim 14 words
An apparatus according to claim 14 including suction box means beneath the deposition surface.
Claim 27
Independent Claim 136 words
A method of forming a material web comprising the steps of causing a composite flow of particulate material in a gaseous medium transport flow into a distribution chamber, precipitating said material from said composite flow on a deposition surface in the distribution chamber to form a web, exposing the composite material flow to control flows of gaseous medium directed from opposite sides of the flow against the same, alternately varying the size of the impulse of the control flows with a frequency in the range of 1 to 50 c.p.s., each control flow consisting of a plurality of jets, whereby the composite material flow is distributed across the width of the deposition surface, measuring the evenness of the formed web and using the measured values for influencing the variation of the impulse of the control flows.
Claim 28
Independent Claim 136 words
A method of forming a material web comprising the steps of causing a composite flow of particulate material in a gaseous medium transport flow into a distribution chamber, precipitating said material from said composite flow on a deposition surface in the distribution chamber to form a web, exposing the composite material flow to control flows of gaseous medium directed from opposite sides of the flow against the same, alternately varying the size of the impulse of the control flows with a frequency in the range of 1 to 50 c.p.s., each control flow consisting of a plurality of jets, whereby the composite material flow is distributed across the width of the deposition surface, measuring the evenness of the formed web and using the measured values for influencing the variation of the impulse of the control flows.
Claim 29
Independent Claim 128 words
A method of forming a material web comprising the steps of causing a composite flow of particulate material in a gaseous transport medium flow into a distribution chamber along the walls thereof whereby the coanda-effect is utilized for distributing the composite material flow across the chamber, precipitating said material from said composite flow on a deposition surface in the distribution chamber, exposing the composite material flow to control flows of gaseous medium directed from opposite sides of the flow against the same, and alternatingly varying the size of the impulse of the control flows with a frequency in the range of 1 to 50 c.p.s., each control flow consisting of a plurality of jets, whereby the composite material flow is distributed across the width of the deposition surface.
Claim 30
Independent Claim 128 words
A method of forming a material web comprising the steps of causing a composite flow of particulate material in a gaseous transport medium flow into a distribution chamber along the walls thereof whereby the coanda-effect is utilized for distributing the composite material flow across the chamber, precipitating said material from said composite flow on a deposition surface in the distribution chamber, exposing the composite material flow to control flows of gaseous medium directed from opposite sides of the flow against the same, and alternatingly varying the size of the impulse of the control flows with a frequency in the range of 1 to 50 c.p.s., each control flow consisting of a plurality of jets, whereby the composite material flow is distributed across the width of the deposition surface.
Claim 31
Independent Claim 139 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of nozzles forming impulse jets directed against the composite material flow, means mounting said nozzles for individual adjustments of their direction or outlet area, and a gas source for said member having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber.
Claim 32
Independent Claim 139 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of nozzles forming impulse jets directed against the composite material flow, means mounting said nozzles for individual adjustments of their direction or outlet area, and a gas source for said member having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber.
Claim 33
Independent Claim 148 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface disposed in a plane therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of aperture means forming impulse jets directed against the composite material flow, mounting means to adjust the directions of said aperture means relative to the plane of the deposition surface, and a gas source for said member having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber.
Claim 34
Independent Claim 148 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface disposed in a plane therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of aperture means forming impulse jets directed against the composite material flow, mounting means to adjust the directions of said aperture means relative to the plane of the deposition surface, and a gas source for said member having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber.
Claim 35
Independent Claim 164 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, each of said members comprising blowing box sections provided with a plurality of aperture means forming impulse jets directed against the composite material flow, alternating with blowing box sections without aperture means, the sections with aperture means on one side of the flow path being opposite the section without aperture means on the other side of the flow path, and a gas source for said members having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber.
Claim 36
Independent Claim 164 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, each of said members comprising blowing box sections provided with a plurality of aperture means forming impulse jets directed against the composite material flow, alternating with blowing box sections without aperture means, the sections with aperture means on one side of the flow path being opposite the section without aperture means on the other side of the flow path, and a gas source for said members having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber.
Claim 37
Independent Claim 132 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of aperture means forming impulse jets directed against the composite material flow, and a gas source for said member having at least one self-oscillating fluidistor means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber.
Claim 38
Independent Claim 132 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of aperture means forming impulse jets directed against the composite material flow, and a gas source for said member having at least one self-oscillating fluidistor means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber.
Claim 39
Independent Claim 136 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of aperture means forming impulse jets directed against the composite material flow, a gas source for said member having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber, and means for supplying additive material to the control flow.
Claim 40
Independent Claim 136 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of aperture means forming impulse jets directed against the composite material flow, a gas source for said member having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber, and means for supplying additive material to the control flow.
Claim 41
Independent Claim 157 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, side wall portions extending from the nozzle to the deposition surface, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of aperture means forming impulse jets directed against the composite material flow, and a gas source for said member having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber, said nozzle, said supply member, and said side wall portions being designed so as to act as a fluidistor.
Claim 42
Independent Claim 157 words
An apparatus for forming a web of particulate material, comprising a distribution chamber, a deposition surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a gaseous medium, side wall portions extending from the nozzle to the deposition surface, and means for distributing the inflowing material across the width of the deposition surface, comprising a supply member for a control gas flow provided on each side of the composite material flow path, said member comprising a blowing box provided with a plurality of aperture means forming impulse jets directed against the composite material flow, and a gas source for said member having means to impart a variable impulse to the control flows to cause said composite flow to be distributed across the full width of the distribution chamber, said nozzle, said supply member, and said side wall portions being designed so as to act as a fluidistor.
Claim 43
Dependent Claim 18 words
An apparatus according to claim 32, characterized in that the wall portions are adjustable with respect to inclination.

References Cited (Backward Citations)

SU247083A1 Cited
SU190555A1 Cited
US2315735A Cited
GB709612A Cited
US2863493A Cited
US2920679A Cited
US3485428A Cited
US3460731A Cited
US3599848A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-07-10 1982-01-09 1982-07-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-07-10 1986-01-09 1986-07-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-07-10 1990-01-09 1990-07-11 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag