US3598680A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tandem air former
Assignee: International Paper Co
•
Filing: 1968-04-18
•
Granted: 1971-08-10
•
Expires: 1988-04-18
Abstract
Abstract A FIBROUS WEB OF NON-UNIFORM, CROSS-SECTIONAL THICKNESS IS FORMED IN A CONTINUOUS MANNER BY AIR LAYING FIBROUS MATERIAL AT A FIRST STATION AND THEN AIR LAYING ADDITIONAL FIBROUS MATERIAL AT A SECOND STATION DOWNSTREAM FROM THE FIRST TO OVERLAP AT LEAST PARTIALLY THE FIBROUS MATERIAL DEPOSITED AT THE FIRST STATION. TO PROVIDE AND MAINTAIN A PRECISE CONFIGURATION FOR THE THICKER PORTION OF THE WEB, A PRESSURE DIFFERENTIAL IS MAINTAINED ACROSS THE WEB BEING FORMED TO CAUSE THE AIR TO FLOW THROUGH THE THICKER PORTION OF THE WEB AS WELL AS THE THINNER PORTIONS OF THE WEB AT THE SUBSTANTIALLY SAME RATE AS IT APPROACHES THE WEB.
Inventors
- 👤 Charles A Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 02:22
CPC Classifications
D; D21; D21H; D21H5/00; D21H5/26; D21H5/2607; D21H5/2628; D21H5/2642; A; A61; A61F; A61F13/00; A61F13/15; A61F13/15577; A61F13/15617; A61F13/15642; D04; D04H; D04H1/00; D04H1/70; D04H1/72; D21H11/00; D21H27/00; D21H27/30
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-09 | 1975-02-08 | 1975-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-09 | 1979-02-08 | 1979-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-09 | 1983-02-08 | 1983-08-10 | $7700.00 | Window Closed / Lapsed |