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US3874997A Expired / Lapsed US ⏱️ 0.0 years remaining

Multiple cylinder drier in a paper machine

Assignee: Valmet Montreal Inc
•
Filing: 1973-03-21
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Granted: 1975-04-01
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Expires: 1993-03-21
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Abstract

Abstract An improvement in the multiple cylinder drier unit of a paper making machine, each drying group of which consists of a number of driers disposed in two rows, one above the other, and lapped by the paper web running through the group in zigzag fashion, supported by a drying wire. The suggested improvement is particularly characterized in that the driers in one row of the drying group are permeable to air and that the multiple cylinder drier also comprises additional driers for creating differential pressures on both sides of the paper web, whereby passage of air through the web is achieved, with the web pressed into contact with the drying wire. According to further, optional features of the invention, the drying means permeable to air are cylindrically shaped drying cylinders, or they consist of a suction chamber substantially confined by the drying wire moving on a support of guiding rolls. In addition, hot air blowing hoods may be arranged around the drying means permeable to air and, within them, suction chambers. The paper web arriving from the press section of the paper machine may be arranged to be attached to the drying wire by the aid of suction means exerting suction through this wire.

Inventors

  • 👤 Matti Kankaanpaa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 15:32
CPC Classifications
D; D21; D21F; D21F5/00; D21F5/02

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 338 words
In a paper machine, a dryer assembly for the drying of a paper web, comprising a row of drying cylinders rotatable about their horizontal axes; perfusion drying means disposed at a vertical distance from the row of drying cylinders and located between said drying cylinders in their interstices; a drying wire permeable to air, the paper web traveling in contact with and supported by said wire from the beginning to the end of the dryer assembly all the way zigzagging from the preceding drying cylinder to the next perfusion drying means, the paper web being disposed on that side of the drying wire where, when running upon a drying cylinder, the paper web is interposed between the drying wire and the mantle surface of the drying cylinder so that hereby, the drying of the paper web by contact drying takes place; said perfusion drying means further comprising, on the side facing the drying wire and adjacent to it, a hot air blowing hood, and on the other side of the drying wire and paper web opposite thereto, a suction chamber extending and limited to the entire joint run of web and wire from one drying cylinder to the next, so that perfusion drying of the paper web takes place substantially on the whole distance of travel of the paper web from the preceding to the next drying cylinder, and so that drying furthermore takes place by impingement drying in the region of the blowing hood; a suction roll at the beginning of the dryer assembly and at a vertical distance from the first drying cylinder so that, by means of said suction roll, the paper web is transferred to be supported by the drying wire; a joint run of the paper web and drying wire between said suction roll and first drying cylinder; a suction box on said joint run on the side facing the drying wire, the effect of the vacuum in this suction box being used to make the paper web adhere to the drying wire.
Claim 2
Dependent Claim 338 words
In a paper machine, a dryer assembly for the drying of a paper web, comprising a row of drying cylinders rotatable about their horizontal axes; perfusion drying means disposed at a vertical distance from the row of drying cylinders and located between said drying cylinders in their interstices; a drying wire permeable to air, the paper web traveling in contact with and supported by said wire from the beginning to the end of the dryer assembly all the way zigzagging from the preceding drying cylinder to the next perfusion drying means, the paper web being disposed on that side of the drying wire where, when running upon a drying cylinder, the paper web is interposed between the drying wire and the mantle surface of the drying cylinder so that hereby, the drying of the paper web by contact drying takes place; said perfusion drying means further comprising, on the side facing the drying wire and adjacent to it, a hot air blowing hood, and on the other side of the drying wire and paper web opposite thereto, a suction chamber extending and limited to the entire joint run of web and wire from one drying cylinder to the next, so that perfusion drying of the paper web takes place substantially on the whole distance of travel of the paper web from the preceding to the next drying cylinder, and so that drying furthermore takes place by impingement drying in the region of the blowing hood; a suction roll at the beginning of the dryer assembly and at a vertical distance from the first drying cylinder so that, by means of said suction roll, the paper web is transferred to be supported by the drying wire; a joint run of the paper web and drying wire between said suction roll and first drying cylinder; a suction box on said joint run on the side facing the drying wire, the effect of the vacuum in this suction box being used to make the paper web adhere to the drying wire.
Claim 3
Dependent Claim 84 words
Dryer assembly according to claim 1, wherein the perfusion drying means comprise a plurality of guiding rolls, the axes of which lie on a curved surface between mutually adjacent drying cylinders, and whereby, under guidance of said guiding rolls, the drying wire travels from one row of drying cylinders to the next row, the perfusion drying means further comprising, adjacent to the outermost guiding rolls, a wall which, together with the drying wire guided by the guiding rolls, confines and encloses said suction chamber.
Claim 4
Dependent Claim 31 words
Dryer assembly according to claim 2, wherein the outermost guiding rolls are suction rolls and are so placed to define a press nip together with the drying cylinders adjacent to them.
Claim 5
Dependent Claim 97 words
Dryer assembly according to claim 1, wherein the perfusion drying means comprises a row of cylinders permeable to air and rotatable about their horizontal axes, said Row being disposed at a vertical distance from the row of drying cylinders and said hot air blowing hood covering said permeable-to-air cylinders on a sector of substantially 180*, and a confining wall located adjacent to the plane defined by the row of drying cylinders and which, together with the runs of the drying wire between the drying cylinders and the cylinder permeable to air, confine and enclose said suction chamber.

References Cited (Backward Citations)

US3318017A Cited
US1615210A Cited
US1767889A Cited
US1844658A Cited
US2091805A Cited
US3320675A Cited
US3685167A Cited
US3671389A Cited
US3576078A Cited
US3733711A Cited
US3816941A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-03-31 1978-09-30 1979-04-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-03-31 1982-09-30 1983-04-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-03-31 1986-09-30 1987-04-01 $7700.00 Window Closed / Lapsed

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