US3853697A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Papermaking machine headbox with an upwardly inclined slice chamber portion, an arcuate portion, and a downwardly inclined portion and containing flexible trailing members
Assignee: Beloit Corp
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Filing: 1973-03-08
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Granted: 1974-12-10
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Expires: 1993-03-08
Abstract
Abstract A headbox construction for delivering stock to a forming surface with the headbox having a chamber leading to a slice chamber with a slice opening and the slice chamber being located and shaped so as to have a first upwardly inclined portion supplied from the headbox chamber through a plate with openings. The slice chamber further has a second arcuate portion and a third downwardly sloping tapered portion leading to the opening. The arcuate portion provides a transition from the upwardly inclined to the downwardly inclined portions, and the headbox decreases in crosssection throughout its length and is provided with rigid trailing elements in the first two portions having flexible selfsupporting trailing elements in the third portion.
Inventors
- 👤 J Parker
- 👤 D Parker
- 👤 R Hergert
- 👤 R Eggen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:02
CPC Classifications
D; D21; D21F; D21F1/00; D21F1/02; D21F1/026; D21F1/028
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
161 words
In a headbox for delivering stock to a forming surface, the headbox having a chamber leading to a slice chamber with a slice opening, the improvement comprising: top and bottom slice walls defining a slice chamber therebetween with the slice chamber having a first upwardly inclined portion, a second arcuate portion leading upwardly and then downwardly, and a third tapered portion leaDing to the opening; thin planar continuous cross-machine extending trailing elements having a rigid planar portion anchored at their upstream ends in said first portion of the slice chamber, a nonflexible portion curved in the direction of said second portion and located therein, and a third portion in the tapered chamber being flexible with the downstream ends unattached and constructed to be self-positionable as to be solely responsive to forces exerted thereon by the stock flowing toward the slice opening; and support means in said first portion of the headbox with the upstream ends of the trailing elements anchored thereto.
Claim 2
Dependent Claim
161 words
In a headbox for delivering stock to a forming surface, the headbox having a chamber leading to a slice chamber with a slice opening, the improvement comprising: top and bottom slice walls defining a slice chamber therebetween with the slice chamber having a first upwardly inclined portion, a second arcuate portion leading upwardly and then downwardly, and a third tapered portion leaDing to the opening; thin planar continuous cross-machine extending trailing elements having a rigid planar portion anchored at their upstream ends in said first portion of the slice chamber, a nonflexible portion curved in the direction of said second portion and located therein, and a third portion in the tapered chamber being flexible with the downstream ends unattached and constructed to be self-positionable as to be solely responsive to forces exerted thereon by the stock flowing toward the slice opening; and support means in said first portion of the headbox with the upstream ends of the trailing elements anchored thereto.
Claim 3
Dependent Claim
57 words
In a headbox for delivering stock to a forming surface, the headbox having a chamber leading to a slice chamber with a slice opening constructed in accordance with claim 1: wherein said support means on which the trailing elements are supported at their upstream ends is a perforate plate extending across the opening to the slice chamber.
Claim 4
Dependent Claim
45 words
In a headbox for delivering stock to a forming surface, the headbox having a headbox chamber leading to a slice chamber having a slice opening constructed in accordance with claim 1: wherein the headbox chamber extends vertically downwardly and opens laterally into the slice chamber.
Claim 5
Dependent Claim
45 words
In a headbox for delivering stock to a forming surface, the headbox having a headbox chamber leading to a slice chamber having a slice opening constructed in accordance with claim 1: wherein the slice chamber continually narrows from the first portion to the slice opening.
Claim 6
Dependent Claim
54 words
In a headbox for delivering stock to a forming surface, the headbox having a headbox chamber leading to a slice chamber having a slice opening constructed in accordance with claim 1: and including means forming a drain opening in the headbox chamber immediately in advance of the slice chamber and at the base thereof.
Claim 7
Dependent Claim
48 words
In a headbox for delivering stock to a forming surface, the headbox having a chamber leading to a slice chamber with a slice opening constructed in accordance with claim 1: wherein said rigid portion of the trailing element is anchored by a pivotal mount at its upstream end.
Claim 8
Dependent Claim
101 words
In a headbox for delivering stock to a forming surface, the headbox having a headbox chamber leading to a slice chamber having a slice opening, the improvement comprising: top and bottom slice walls dfining a slice chamber therebetween with the slice chamber extending upwardly and then downwardly toward the slice opening; a plurality of trailing elements positioned within the chamber supported at their upstream ends with their downstream ends unattached whereby the stock tends to avoid the accumulation of air in the slice chamber; and support means in the slice chamber with the upstream ends of the trailing elements attached thereto.
Claim 9
Dependent Claim
101 words
In a headbox for delivering stock to a forming surface, the headbox having a headbox chamber leading to a slice chamber having a slice opening, the improvement comprising: top and bottom slice walls dfining a slice chamber therebetween with the slice chamber extending upwardly and then downwardly toward the slice opening; a plurality of trailing elements positioned within the chamber supported at their upstream ends with their downstream ends unattached whereby the stock tends to avoid the accumulation of air in the slice chamber; and support means in the slice chamber with the upstream ends of the trailing elements attached thereto.
Claim 10
Dependent Claim
54 words
In a headbox for delivering stock to a forming surface, the headbox having a headbox chamber leading to a slice chamber having a slice opening constructed in accordance with claim 7. wherein the upwardly extending portion is of a greater size than the downwardly extending portion so that the speed of stock flow increases.
Claim 11
Dependent Claim
59 words
In a headbox for delivering stock to a forming surface, the headbox having a headbox chamber leading to a slice chamber having a slice opening constructed in accordance with claim 7: wherein the first portion curves upwardly and turns to join the downwardly curving second portion and the trailing elements are correspondingly curved with the curved portions being rigid.
Claim 12
Dependent Claim
74 words
In a headbox for delivering stock to a forming surface, the headbox having a headbox chamber leading to a slice chamber having a slice opening constructed in accordance with claim 7: wherein said trailing elements have a first rigid portion and a downstream flexible portion attached at their upstream ends only and the flexible portions constructed to be self-positionable and solely responsive to forces exerted thereon by the stock flowing toward the Slice opening.
Claim 13
Dependent Claim
65 words
In a headbox for delivering stock to a forming surface, the headbox having a headbox chamber leading to a slice chamber having a slice opening constructed in accordance with claim 7: including means for adjusting the position of the roof of the slice chamber so as to change the size of the slice opening and the trailing elements are removably positioned within the slice chamber.
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) | 1977-12-09 | 1978-06-10 | 1978-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-09 | 1982-06-10 | 1982-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-09 | 1986-06-10 | 1986-12-10 | $7700.00 | Window Closed / Lapsed |