US4196689A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for drying paper webs or the like
Assignee: JM Voith GmbH
•
Filing: 1978-08-15
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Granted: 1980-04-08
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Expires: 1998-08-15
Abstract
Abstract A Yankee clyinder whose internally heated shell consists of steel or cast iron and is provided with an external layer of pure or alloyed copper, molybdenum, tungsten or another metal whose thermal conductivity greatly exceeds (and preferably amounts to at least twice) the thermal conductivity of the material of the shell. The thickness of the layer is in the range of 0.4-2 millimeters, and the thermal expansion coefficient of its material is identical to or approximates that of the material of the shell. The layer can be applied to the periphery of the shell in molten state in the form of a finely atomized spray. The drying action of such cylinder upon a running paper web greatly exceeds the drying action of a cylinder whose shell consists exclusively of cast iron or steel.
Inventors
- 👤 Robert Wolf
- 👤 Georg Zurn
- 👤 Christian Schiel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:06
CPC Classifications
D; D21; D21F; D21F5/00; D21F5/02; D21F5/021; Y; Y10; Y10S; Y10S165/00; Y10S165/135; Y10S165/139; Y10S165/156
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
117 words
Apparatus for reducing the moisture content of running paper webs or the like, particularly, in a Yankee machine, comprising a rotary member including a hollow cylindrical shell which is internally heated by a fluid at elevated pressure and externally juxtaposed over a large area with the web during the operation of the apparatus, and which consists of a first metallic material selected from the group consisting of cast iron and steel, and means for increasing heat transfer within said area from said rotary member to the web, including a web-contacting layer applied to the periphery of said shell and consisting of a second metallic material whose thermal conductivity considerably exceeds the thermal conductivity of said first material.
Claim 2
Dependent Claim
117 words
Apparatus for reducing the moisture content of running paper webs or the like, particularly, in a Yankee machine, comprising a rotary member including a hollow cylindrical shell which is internally heated by a fluid at elevated pressure and externally juxtaposed over a large area with the web during the operation of the apparatus, and which consists of a first metallic material selected from the group consisting of cast iron and steel, and means for increasing heat transfer within said area from said rotary member to the web, including a web-contacting layer applied to the periphery of said shell and consisting of a second metallic material whose thermal conductivity considerably exceeds the thermal conductivity of said first material.
Claim 3
Dependent Claim
18 words
Apparatus as defined in claim 1, wherein the thickness of said layer is between 0.4 and 2 millimeters.
Claim 4
Dependent Claim
26 words
Apparatus as defined in claim 1, wherein the thermal expansion coefficient of said first material at least approximates the thermal expansion coefficient of said second material.
Claim 5
Dependent Claim
24 words
Apparatus as defined in claim 1, wherein said layer is a molten-state spray-deposited layer of said second material on the periphery of said shell.
Claim 6
Dependent Claim
23 words
Apparatus as defined in claim 1, wherein said second material is selected from the group consisting of copper, molybdenum, tungsten and their alloys.
Claim 7
Dependent Claim
61 words
Apparatus as defined in claim 1, further comprising means for pressing successive increments of the web against said layer in a first region, means for separating the web from said layer in a second region located downstream of said first region, as considered in the direction of rotation of said member, and a dryer hood overlying said layer intermediate said regions.
Claim 8
Dependent Claim
14 words
Apparatus as defined in claim 1, wherein said rotary member is a Yankee cylinder.
Claim 9
Dependent Claim
22 words
Apparatus as defined in claim 1, wherein the thickness of said layer is a minute fraction of the thickness of said shell.
References Cited (Backward Citations)
US1252319A
Cited
US2259024A
Cited
US2433121A
Cited
US2958742A
Cited
US2964297A
Cited
US4081913A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-04-08 | 1983-10-08 | 1984-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-08 | 1987-10-08 | 1988-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-08 | 1991-10-08 | 1992-04-08 | $7700.00 | Window Closed / Lapsed |