US3336424A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermoplastic sheet formation
Assignee: Dow Chemical Co
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Filing: 1963-10-02
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Granted: 1967-08-15
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Expires: 1983-10-02
Abstract
No abstract record available.
Inventors
- 👤 Grant W Cheney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:41
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/10; B29C51/26; B29C51/30; B29C51/32
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
104 words
A METHOD FOR FORMING THERMOPLASTIC SHEET MATERIAL INTO A GIVEN SHAPE COMPRISING THE STEPS OF, ARRANGING A MOLDABLE SHEET OF THERMOPLASTIC MATERIAL ABOVE A MOLD CAVITY, PLACING AN AIR PERVIOUS MEANS ADJACENT AN UPPER SURFACE OF THE MATERIAL, APPLYING A FIRST PRESSURE DIFFERENTIAL TO THE MATERIAL TO FORCE IT INTO ENGAGEMENT WITH THE AIR PERVIOUS MEANS, AND APPLYING A SECOND PRESSURE DIFFERENTIAL, WHILE MAINTAINING SAID FIRST PRESSURE DIFFERENTIAL, TO THE SHEET MATERIAL TO PEEL IT AWAY FROM ENGAGEMENT WITH THE AIR PREVIOUS MEANS, IN A DIRECTION PROGRESSING RADIALLY INWARD, TO FORCE THE MATERIAL INTO FULL ENGAGEMENT WITH A RECESS FORMED IN THE MOLD CAVITY.
Claim 2
Independent Claim
104 words
A METHOD FOR FORMING THERMOPLASTIC SHEET MATERIAL INTO A GIVEN SHAPE COMPRISING THE STEPS OF, ARRANGING A MOLDABLE SHEET OF THERMOPLASTIC MATERIAL ABOVE A MOLD CAVITY, PLACING AN AIR PERVIOUS MEANS ADJACENT AN UPPER SURFACE OF THE MATERIAL, APPLYING A FIRST PRESSURE DIFFERENTIAL TO THE MATERIAL TO FORCE IT INTO ENGAGEMENT WITH THE AIR PERVIOUS MEANS, AND APPLYING A SECOND PRESSURE DIFFERENTIAL, WHILE MAINTAINING SAID FIRST PRESSURE DIFFERENTIAL, TO THE SHEET MATERIAL TO PEEL IT AWAY FROM ENGAGEMENT WITH THE AIR PREVIOUS MEANS, IN A DIRECTION PROGRESSING RADIALLY INWARD, TO FORCE THE MATERIAL INTO FULL ENGAGEMENT WITH A RECESS FORMED IN THE MOLD CAVITY.
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) | 1970-08-14 | 1971-02-13 | 1971-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-08-14 | 1975-02-13 | 1975-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-08-14 | 1979-02-13 | 1979-08-15 | $7700.00 | Window Closed / Lapsed |