US3815256A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Grooved dryer
Assignee: Beloit Corp
•
Filing: 1973-03-12
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Granted: 1974-06-11
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Expires: 1993-03-12
Abstract
Abstract The method and apparatus for drying moist traveling paper webs in a high speed papermaking machine wherein the dryer drums have peripheral surfaces provided with narrow venting grooves in particular configuration to facilitate air and steam ventilation carried over the dryer drum surface by the oncoming paper web.
Inventors
- 👤 D Ely
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:01
CPC Classifications
D; D21; D21F; D21F5/00; D21F5/02; D21F5/021
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
168 words
A high speed web drying apparatus for paper machines including: a plurality of heated dryer drums arranged in an upper and lower tier, a web traveling successively around dryer drums of the upper and lower tier, upper and lower felts of pervious material which allow gaseous fluids to pass therethrough, guide rolls positioned between the dryer drums of each tier for guiding the felts against the respective dryer drums in the upper and lower tiers with the web therebetween, said drums having peripheral surfaces provided with a web traction means to urge the traveling web toward said dryer surfaces thereof enhancing the web-to-dryer surface contact to prevent deviation of the web from its normal path around said dryer surfaces, said traction means comprising a plurality of alternating generally circumferentially aligned grooves and ridges wherein a portion of each groove has a vacuum zone by virtue of the velocity of the air flowing out of the groove being greater than the velocity of the air flowing into the groove.
Claim 2
Dependent Claim
168 words
A high speed web drying apparatus for paper machines including: a plurality of heated dryer drums arranged in an upper and lower tier, a web traveling successively around dryer drums of the upper and lower tier, upper and lower felts of pervious material which allow gaseous fluids to pass therethrough, guide rolls positioned between the dryer drums of each tier for guiding the felts against the respective dryer drums in the upper and lower tiers with the web therebetween, said drums having peripheral surfaces provided with a web traction means to urge the traveling web toward said dryer surfaces thereof enhancing the web-to-dryer surface contact to prevent deviation of the web from its normal path around said dryer surfaces, said traction means comprising a plurality of alternating generally circumferentially aligned grooves and ridges wherein a portion of each groove has a vacuum zone by virtue of the velocity of the air flowing out of the groove being greater than the velocity of the air flowing into the groove.
Claim 3
Dependent Claim
102 words
A high speed web drying apparatus for paper machines in accordance with claim 1, wherein: the grooves have an Axial dimension at the groove periphery substantially in the range of from 0.025 to 0.200 inches and extend generally radially inward for a distance substantially in the range of from 0.015 to 0.200 inches along generally parallel sidewalls, said sidewalls terminating in a bottom portion having a radius one-half of the groove width and the ridges each present a generally circumferentially outer peripheral land area having an axial dimension substantially in the range of from 0.1 to 2.0 inches at the roll periphery.
Claim 4
Dependent Claim
48 words
A high speed web drying apparatus for paper machines in accordance with claim 1, wherein: the web traction means on the peripheral surfaces of the dryer drums provide a relatively greater surface area on said surfaces for increased heat transfer from said dryer surface to the traveling web.
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) | 1977-06-10 | 1977-12-10 | 1978-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-10 | 1981-12-10 | 1982-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-10 | 1985-12-10 | 1986-06-11 | $7700.00 | Window Closed / Lapsed |