US4381612A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dryer fabric for papermaking machine and method
Assignee: Wangner Systems Corp
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Filing: 1981-06-03
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Granted: 1983-05-03
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Expires: 2001-06-03
Abstract
Abstract A dryer fabric and method for drying a web W of paper material is disclosed which includes passing the web through a dryer having a plurality of heated cylinders and holding the web in contact against the heated cylinders by means of a dryer fabric 24 arranged as an endless traveling dryer fabric. The dryer fabric includes a plurality of elongated helix means 30 extending in a cross-wise direction constructed from a polymeric material characterized by stress and heat resistance to which said fabric is subjected during endless travel about the rollers at elevated drying temperatures. Joint means 32 joins adjacent ones of helix means successively together in a machine direction to form an endless belt of desired dimension. Spaced upper and lower generally parallel loop runs 34a and 34b in the helix means 30 define a smooth generally flat paper contacting surface. An open mesh 36 is defined in the fabric between adjacent joint means and runs of loops 34 along the cross-wise and machine directions of the fabric through which heated vapor and the like flow and are transferred outwardly from the paper web. Polymeric filler strands are inserted across the helix means closing the mesh to reduce flow. The edges of the fabric are heat sealed retaining the filler strands and helix means as integral fabric structure. In one embodiment, the filler strand includes low-melt nylon strands 42 which are heated to expand and occupy the helix strips more completely and which interlock the upper and lower loop runs providing a more stable fabric structure.
Inventors
- 👤 Samuel E. Shank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:04
CPC Classifications
D; D21; D21F; D21F1/00; D21F1/0027; D21F1/0072
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
270 words
In apparatus for drying a web of paper material in a dryer section of a papermaking machine which includes a plurality of heated cylinders over which the web travels for drying, an endless traveling dryer belt carried about rollers and adjacent said cylinders contacting said web to hold said web against said heated cylinders for drying, air defined in a space between said cylinder and dryer fabric being forced through said web and dryer belt drying said paper web, said dryer belt being open to the passage of air therethrough, the combination of a non-woven fabric belt which includes a plurality of elongated helix means extending in a cross-wise direction constructed from a polymeric material having a degree of plasticity for accommodating stress during repeated travel over said rollers at elevated drying temperatures, said helix means including flattened loops having generally parallel upper and lower runs of said material presenting a smooth generally flat web contacting surface, joint means joining adjacent ones of said helix means successively together in a machine direction to provide an endless dryer belt of desired dimension; an open fabric mesh defined between said joint means and runs of said loops; polymeric filler means capable of withstanding said drying temperatures inserted between said runs in each said helix loop across the entire width of said fabric in said cross-wise direction to close said fabric mesh and control the flow of air through said dryer belt and reduce fluttering of said web of paper thereagainst during drying and a heated sealed seam along edges of said fabric sealing said filler means and fabric providing integral fabric structure.
Claim 2
Dependent Claim
270 words
In apparatus for drying a web of paper material in a dryer section of a papermaking machine which includes a plurality of heated cylinders over which the web travels for drying, an endless traveling dryer belt carried about rollers and adjacent said cylinders contacting said web to hold said web against said heated cylinders for drying, air defined in a space between said cylinder and dryer fabric being forced through said web and dryer belt drying said paper web, said dryer belt being open to the passage of air therethrough, the combination of a non-woven fabric belt which includes a plurality of elongated helix means extending in a cross-wise direction constructed from a polymeric material having a degree of plasticity for accommodating stress during repeated travel over said rollers at elevated drying temperatures, said helix means including flattened loops having generally parallel upper and lower runs of said material presenting a smooth generally flat web contacting surface, joint means joining adjacent ones of said helix means successively together in a machine direction to provide an endless dryer belt of desired dimension; an open fabric mesh defined between said joint means and runs of said loops; polymeric filler means capable of withstanding said drying temperatures inserted between said runs in each said helix loop across the entire width of said fabric in said cross-wise direction to close said fabric mesh and control the flow of air through said dryer belt and reduce fluttering of said web of paper thereagainst during drying and a heated sealed seam along edges of said fabric sealing said filler means and fabric providing integral fabric structure.
Claim 3
Dependent Claim
18 words
The apparatus of claim 1 wherein said filler includes elongated strands of polymeric material having an oblong cross-section.
Claim 4
Dependent Claim
19 words
The apparatus of claim 1 wherein said filler means includes elongated cross-wise strands having a generally flat rectangular cross-section.
Claim 5
Dependent Claim
51 words
The apparatus of claim 1 wherein said filler means includes an elongated strip of polymeric material heated after insertion to cause expansion of said filler means more completely closing said fabric to substantially reduce the permeability thereof and maintain said filler means and helix fabric tightly together as integral fabric structure.
Claim 6
Dependent Claim
15 words
The apparatus of claim 1 wherein said filler means includes strips of low-melt polymeric material.
Claim 7
Dependent Claim
27 words
The apparatus of claim 5 wherein said low-melt polymeric material has a melting point of approximately 350 degrees farenheit at which it begins to swell and expand.
Claim 8
Dependent Claim
27 words
The apparatus of claim 4 wherein said low-melt polymeric material has a melt point of approximately 350 degrees farenheit at which it begins to swell and expand.
Claim 9
Independent Claim
252 words
A method of drying a web of paper material which includes passing the web through a dryer having a plurality of heated cylinders, holding said web in contact against said heated cylinders by contacting said web with an endless travelling dryer fabric, said dryer fabric having controlled air passage which permits passage of air therethrough and through said web of paper without excessive sheet flutter due to air pumping through said fabric, said method including providing an endless travelling dryer fabric which comprises: a plurality of elongated helix means extending in a cross-wise direction constructed from a polymeric material characterized by stress and heat resistance to which said fabric is subjected during endless travel about rollers at elevated drying temperatures; joint means joining adjacent ones of said helix means successively together in a machine direction to form an endless belt of desired dimension; spaced upper and lower generally parallel loop runs included in said helix means defining a smooth generally flat contacting surface; an open mesh defined in said fabric between adjacent joint means and runs of said loops along the cross-wise and machine dimensions of said fabric through which heated vapor and the like flow and are transferred outwardly from said paper web; polymeric filler means inserted across said helix means closing said mesh to reduce said flow and control air pumping through said fabric and reduce fluttering of said web of paper thereagainst; means sealing edges of said fabric retaining said filler means and helix means as integral fabric structure.
Claim 10
Independent Claim
252 words
A method of drying a web of paper material which includes passing the web through a dryer having a plurality of heated cylinders, holding said web in contact against said heated cylinders by contacting said web with an endless travelling dryer fabric, said dryer fabric having controlled air passage which permits passage of air therethrough and through said web of paper without excessive sheet flutter due to air pumping through said fabric, said method including providing an endless travelling dryer fabric which comprises: a plurality of elongated helix means extending in a cross-wise direction constructed from a polymeric material characterized by stress and heat resistance to which said fabric is subjected during endless travel about rollers at elevated drying temperatures; joint means joining adjacent ones of said helix means successively together in a machine direction to form an endless belt of desired dimension; spaced upper and lower generally parallel loop runs included in said helix means defining a smooth generally flat contacting surface; an open mesh defined in said fabric between adjacent joint means and runs of said loops along the cross-wise and machine dimensions of said fabric through which heated vapor and the like flow and are transferred outwardly from said paper web; polymeric filler means inserted across said helix means closing said mesh to reduce said flow and control air pumping through said fabric and reduce fluttering of said web of paper thereagainst; means sealing edges of said fabric retaining said filler means and helix means as integral fabric structure.
Claim 11
Dependent Claim
19 words
The apparatus of claim 8 wherein said filler means inclues elongated cross-wise strands having a generally flat rectangular cross-section.
Claim 12
Dependent Claim
18 words
The apparatus of claim 8 wherein said filler includes elongated strands of polymeric material having an oblong cross-section.
Claim 13
Dependent Claim
26 words
The method of claim 8 wherein said fabric includes at least a pair of elongated strands of said filler material inserted between next adjacent joint means.
Claim 14
Dependent Claim
48 words
The method of claim 8 wherein said filler means is provided by a filler strip inserted in said helix means across the width of said fabric and heated to expand and more completely and tightly fill same substantially closing said mesh and providing a more integral fabric structure.
Claim 15
Independent Claim
169 words
A method of constructing a dryer fabric for a dryer section of a papermaking machine so as to have a desired permeability and control of air flow therethrough comprising: providing a series of elongated helix means oriented in a cross-wise direction in said fabric constructed from a polymeric material having open helix loops defined by upper and lower generally parallel loop runs of said material; joining said helix means successively to one another to form a basic endless dryer fabric of desired dimension in a machine direction having a paper contacting surface which includes an open mesh permeable to fluids; closing said mesh of said basic dryer fabric by inserting polymeric filler means inside said helix loops across the entire width of said fabric in said cross-wise direction to reduce the permeability of said fabric and control the flow of air through said fabric and reduce paper flutter during drying; and sealing lateral edges of said polymeric fabric to retain said fabric and filler means as integral fabric structure.
Claim 16
Independent Claim
169 words
A method of constructing a dryer fabric for a dryer section of a papermaking machine so as to have a desired permeability and control of air flow therethrough comprising: providing a series of elongated helix means oriented in a cross-wise direction in said fabric constructed from a polymeric material having open helix loops defined by upper and lower generally parallel loop runs of said material; joining said helix means successively to one another to form a basic endless dryer fabric of desired dimension in a machine direction having a paper contacting surface which includes an open mesh permeable to fluids; closing said mesh of said basic dryer fabric by inserting polymeric filler means inside said helix loops across the entire width of said fabric in said cross-wise direction to reduce the permeability of said fabric and control the flow of air through said fabric and reduce paper flutter during drying; and sealing lateral edges of said polymeric fabric to retain said fabric and filler means as integral fabric structure.
Claim 17
Dependent Claim
55 words
The method of claim 13 wherein the step of closing said open mesh includes inserting at least one strand of polymeric material inside each said helix loop and subjecting said fabric to heat-treatment causing said strand to flow and expand to thereby more completely occupy said loop and mesh area than in its untreated state.
Claim 18
Dependent Claim
22 words
The method of claim 13 wherein said filler means is provided by a strand of polymeric material having a generally flat configuration.
Claim 19
Dependent Claim
20 words
The method of claim 13 including heat treating said basic fabric to heat set said fabric making same thermally stable.
Claim 20
Dependent Claim
18 words
The apparatus of claim 13 wherein said filler includes elongated strands of polymeric material having an oblong cross-section.
Claim 21
Dependent Claim
26 words
The method of claim 13 wherein said fabric includes at least a pair of elongated strands of said filler material inserted between next adjacent joint means.
Claim 22
Dependent Claim
23 words
The method of claim 14 including heat treating said polymeric material at a temperature below the heat set temperature of said basic fabric.
Claim 23
Dependent Claim
19 words
The method of claim 19 wherein said fabric is heat set at a temperature of approximately 420 degrees farenheit.
Claim 24
Dependent Claim
17 words
The method of claim 19 including heat treating said fabric prior to heat treating said filler strip.
Claim 25
Dependent Claim
21 words
The method of claim 19 including heat treating said filler strip prior to and simultaneously with heat treating said basic fabric.
Claim 26
Dependent Claim
268 words
A dryer belt fabric for use with apparatus for drying a web of paper material in a dryer section of a papermaking machine which includes a plurality of heated cylinders over which the web travels for drying and said fabric is arranged as an endless traveling dryer belt carried about rollers and adjacent said cylinders contacting said web to hold said web against said heated cylinders forcing out air in an area between said web and cylinder for drying, wherein said dryer belt fabric comprises: a non-woven heat set fabric which includes a plurality of elongated helix means extending in a cross-wise direction constructed from a polymeric material having a degree of plasticity of accommodating stress during repeated travel over said rollers at elevated drying temperatures; said helix means including flattened loops having generally parallel upper and lower runs of said material presenting asmooth generally flat web contacting surface; joint means joining adjacent ones of said helix means successively together in a machine direction to provide an endless dryer belt of desired dimension; an open fabric mesh defined between said joint means and runs of said loops through which air flows; polymeric filler means capable of withstanding said drying temperatures inserted between said runs in each said helix loop across the entire width of said fabric in said cross-wise direction to close said fabric mesh and control the flow of air through said dryer belt and reduce fluttering of said web of paper against said fabric during drying; and a heat sealed seam along edges of said fabric sealing said filler means and fabric providing integral fabric structure.
Claim 27
Dependent Claim
268 words
A dryer belt fabric for use with apparatus for drying a web of paper material in a dryer section of a papermaking machine which includes a plurality of heated cylinders over which the web travels for drying and said fabric is arranged as an endless traveling dryer belt carried about rollers and adjacent said cylinders contacting said web to hold said web against said heated cylinders forcing out air in an area between said web and cylinder for drying, wherein said dryer belt fabric comprises: a non-woven heat set fabric which includes a plurality of elongated helix means extending in a cross-wise direction constructed from a polymeric material having a degree of plasticity of accommodating stress during repeated travel over said rollers at elevated drying temperatures; said helix means including flattened loops having generally parallel upper and lower runs of said material presenting asmooth generally flat web contacting surface; joint means joining adjacent ones of said helix means successively together in a machine direction to provide an endless dryer belt of desired dimension; an open fabric mesh defined between said joint means and runs of said loops through which air flows; polymeric filler means capable of withstanding said drying temperatures inserted between said runs in each said helix loop across the entire width of said fabric in said cross-wise direction to close said fabric mesh and control the flow of air through said dryer belt and reduce fluttering of said web of paper against said fabric during drying; and a heat sealed seam along edges of said fabric sealing said filler means and fabric providing integral fabric structure.
Claim 28
Dependent Claim
39 words
The apparatus of claim 1 wherein said filler means including an elongated strand of a low-melt polymeric material having a melt point below the heat set point of said fabric at which said material begins to swell and flow.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-05-02 | 1986-11-01 | 1987-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-02 | 1990-11-01 | 1991-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-02 | 1994-11-01 | 1995-05-03 | $7700.00 | Window Closed / Lapsed |