US3179726A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vacuum corrugator
Assignee: Johns Manville Corp
•
Filing: 1964-01-02
•
Granted: 1965-04-20
•
Expires: 1984-01-02
Abstract
No abstract record available.
Inventors
- 👤 Walter M Perry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:31
CPC Classifications
B; B28; B28B; B28B1/00; B28B1/52; B28B1/528
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
172 words
A METHOD OF CORRUGATING A PLASTIC FIBROUS-CEMENT SHEET ON A PERFORATED DIE HAVING CRESTS AND VALLEYS, COMPRISING THE STEPS OF: (1) PLACING AN AIR PERVIOUS, SUBSTANTIALLY NONSTRETCHABLE, FLEXIBLE SHEET OVER THE DIE SURFACE, (2) APPLYING A TENSIONING FORCE TO THE SHEET IN A DIRECTION TRANSVERSELY OF THE DIRECTION OF THE CRESTS AND VALLEYS, THE TENSIONING FORCE HOLDING THE SHEET TAUT ACROSS THE DIE CRESTS BUT PERMITTING, IN RESPONSE TO SUFFICIENT FORCE EXERTED TRANSVERSELY OF THE SHEET AND ON A PORTION OF THE SHEET ADJACENT A DIE VALLEY, SIMULTANEOUS MOVEMENT OF THE TAUT SHEET OVER THE DIE CRESTS IN A DIRECTION OPPOSITE TO THE TENSIONING FORCE AND MOVEMENT OF SAID PORTION OF THE SHEET TOWARD THE DIE VALLEY, (3) PLACING A PLASTIC FIBROUS-CEMENT SHEET ON THE TAUT FLEXIBLE SHEET, AND (4) APPLYING SUCTION TO A PREDETERMINED VALLEY OF THE DIE, THE FORCE OF THE SUCTION OVERCOMING THE TENSIONING FORCE, WHEREBY A PORTION OF THE FLEXIBLE SHEET AND THE FIBROUS-CEMENT SHEET SUPPORTED THEREON ARE DRAWN INTO THE VALLEY TO CONFORM TO THE SHAPE THEREOF.
Claim 2
Independent Claim
172 words
A METHOD OF CORRUGATING A PLASTIC FIBROUS-CEMENT SHEET ON A PERFORATED DIE HAVING CRESTS AND VALLEYS, COMPRISING THE STEPS OF: (1) PLACING AN AIR PERVIOUS, SUBSTANTIALLY NONSTRETCHABLE, FLEXIBLE SHEET OVER THE DIE SURFACE, (2) APPLYING A TENSIONING FORCE TO THE SHEET IN A DIRECTION TRANSVERSELY OF THE DIRECTION OF THE CRESTS AND VALLEYS, THE TENSIONING FORCE HOLDING THE SHEET TAUT ACROSS THE DIE CRESTS BUT PERMITTING, IN RESPONSE TO SUFFICIENT FORCE EXERTED TRANSVERSELY OF THE SHEET AND ON A PORTION OF THE SHEET ADJACENT A DIE VALLEY, SIMULTANEOUS MOVEMENT OF THE TAUT SHEET OVER THE DIE CRESTS IN A DIRECTION OPPOSITE TO THE TENSIONING FORCE AND MOVEMENT OF SAID PORTION OF THE SHEET TOWARD THE DIE VALLEY, (3) PLACING A PLASTIC FIBROUS-CEMENT SHEET ON THE TAUT FLEXIBLE SHEET, AND (4) APPLYING SUCTION TO A PREDETERMINED VALLEY OF THE DIE, THE FORCE OF THE SUCTION OVERCOMING THE TENSIONING FORCE, WHEREBY A PORTION OF THE FLEXIBLE SHEET AND THE FIBROUS-CEMENT SHEET SUPPORTED THEREON ARE DRAWN INTO THE VALLEY TO CONFORM TO THE SHAPE THEREOF.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-04-19 | 1968-10-19 | 1969-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-04-19 | 1972-10-19 | 1973-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-04-19 | 1976-10-19 | 1977-04-20 | $7700.00 | Window Closed / Lapsed |