US4539075A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Perforated sheet for the head box of a paper machine
Assignee: Tampella Oy AB
•
Filing: 1983-12-19
•
Granted: 1985-09-03
•
Expires: 2003-12-19
Abstract
Abstract Perforated sheet for a head box of a paper machine, the perforated sheet being provided with a number of parallel flow passages starting from a common front face. The perforated sheet is provided with a set of feeding ducts which can be connected to a source of flushing liquid and which is connected, by means of flushing ducts, to the front face of the perforated sheet. The perforated sheet preferably consists of several rod elements, each of which is provided with a flow passage and which have been assembled as parallel to each other, side by side and one above the other, into an integrated package.
Inventors
- 👤 Pekka Majaniemi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:55
CPC Classifications
D; D21; D21F; D21F1/00; D21F1/02; D21F1/022; D21F1/026
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
126 words
A perforated sheet for a head box of a paper machine, comprising several rod elements each including a flow passage, said flow passages arranged in parallel into an integrated package and starting from a common front face of said perforated sheet and having inlet openings; said rod elements each being integrally formed with a feeding duct, said feeding ducts being substantially parallel to said front face of said perforated sheet and being connected to a source of flushing liquid to feed said flushing liquid through said feeding ducts; and said rod elements each being integrally formed with a flushing duct, said flushing ducts connecting said feeding ducts to said front face, and terminating in said front face at points between said inlet openings of said passages.
Claim 2
Dependent Claim
126 words
A perforated sheet for a head box of a paper machine, comprising several rod elements each including a flow passage, said flow passages arranged in parallel into an integrated package and starting from a common front face of said perforated sheet and having inlet openings; said rod elements each being integrally formed with a feeding duct, said feeding ducts being substantially parallel to said front face of said perforated sheet and being connected to a source of flushing liquid to feed said flushing liquid through said feeding ducts; and said rod elements each being integrally formed with a flushing duct, said flushing ducts connecting said feeding ducts to said front face, and terminating in said front face at points between said inlet openings of said passages.
Claim 3
Dependent Claim
25 words
Perforated sheet as claimed in claim 1, wherein said feeding duct in a rod element surrounds said flow passage annularly and is radially open outwards.
Claim 4
Dependent Claim
42 words
Perforated sheet as claimed in claim 2, wherein each rod element is provided with at least one flushing duct parallel to said flow passage and placed in the face of a portion of material between said feeding duct and said front face.
Claim 5
Dependent Claim
33 words
Perforated sheet as claimed in claim 1, wherein said rod elements have been assembled into a support frame and connected to said frame by means of fastening rods extending between said rod elements.
Claim 6
Dependent Claim
21 words
Perforated sheet as claimed in claim 4, wherein each rod element is provided with a locking groove for said fastening rods.
Claim 7
Dependent Claim
16 words
Perforated sheet as claimed in claim 1, wherein said rod elements have a rectangular cross-sectional shape.
References Cited (Backward Citations)
US2736247A
Cited
US3791918A
Cited
US3962031A
Cited
US3970513A
Cited
US4146427A
Cited
US4198270A
Cited
SE422091B
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-02 | 1989-03-04 | 1989-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-02 | 1993-03-04 | 1993-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-02 | 1997-03-04 | 1997-09-03 | $7700.00 | Window Closed / Lapsed |