US2832994A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Accessory apparatus for making blown polystyrene film
Assignee: Dow Chemical Co
•
Filing: 1956-08-16
•
Granted: 1958-05-06
•
Expires: 1976-08-16
Abstract
No abstract record available.
Inventors
- 👤 Harold G Ahlich
- 👤 Eugene F Habowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:19
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/88; B29C48/885; B29C48/03; B29C48/09; B29C48/10; B29C48/911; B29C48/9115; B29C48/912; B29C48/001; B29C48/0018; B29C48/0019
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
155 words
ACCESSORY APPARATUS FOR USE IN THE TRAPPED BUBBLE PROCESS FOR MAKING THERMOPLASTIC FILM COMPRISING, IN ASSOCIATION WITH A TUBE FORMING PLASTIC EXTRUDER AND A PAIR OF PINCH ROLLS DISPOSED WITH THEIR NIP CENTERED TRANSVERSELY ON THE EXTRUSION CENTERLINE, A HOLLOW METAL RING OF INTERNAL DIAMETER GREATER THAN THAT OF THE ORIFICE OF THE TUBE FORMING EXTRUDER BUT SMALLER THAN THAT OF AN INFLATED FILM TUBE TO BE PRODUCED IN THE APPARATUS, SAID RING HAVING AN INLET AND AN OUTLET FOR CIRCULATION THEREIN OF LIQUID COOLANT, SAID HAVING A SMOOTH METAL BEAD CIRCUMFERENTIALLY DISPOSED ALONG ONE EDGE OF THE INNER FACE OF SAID RING, TO PROVIDE A SINGLE CIRCUMFERENTIAL LINE OF CONTACT BETWEEN THE RING AND SUCH INFLATED FILM TUBE, THE RING BEING MOUNTED COAXIALLY WITH THE TUBE FORMING EXTRUSION DIE AND SPACED THEREFROM A SHORT DISTANCE TO SERVE AS A GUIDE FOR INFLATED PLASTIC FILM TUBE DURING OPERATION OF THE APPARATUS FOR IT INTENDED PURPOSE.
Claim 2
Dependent Claim
155 words
ACCESSORY APPARATUS FOR USE IN THE TRAPPED BUBBLE PROCESS FOR MAKING THERMOPLASTIC FILM COMPRISING, IN ASSOCIATION WITH A TUBE FORMING PLASTIC EXTRUDER AND A PAIR OF PINCH ROLLS DISPOSED WITH THEIR NIP CENTERED TRANSVERSELY ON THE EXTRUSION CENTERLINE, A HOLLOW METAL RING OF INTERNAL DIAMETER GREATER THAN THAT OF THE ORIFICE OF THE TUBE FORMING EXTRUDER BUT SMALLER THAN THAT OF AN INFLATED FILM TUBE TO BE PRODUCED IN THE APPARATUS, SAID RING HAVING AN INLET AND AN OUTLET FOR CIRCULATION THEREIN OF LIQUID COOLANT, SAID HAVING A SMOOTH METAL BEAD CIRCUMFERENTIALLY DISPOSED ALONG ONE EDGE OF THE INNER FACE OF SAID RING, TO PROVIDE A SINGLE CIRCUMFERENTIAL LINE OF CONTACT BETWEEN THE RING AND SUCH INFLATED FILM TUBE, THE RING BEING MOUNTED COAXIALLY WITH THE TUBE FORMING EXTRUSION DIE AND SPACED THEREFROM A SHORT DISTANCE TO SERVE AS A GUIDE FOR INFLATED PLASTIC FILM TUBE DURING OPERATION OF THE APPARATUS FOR IT INTENDED PURPOSE.
References Cited (Backward Citations)
US2641022A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-05-05 | 1961-11-04 | 1962-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-05-05 | 1965-11-04 | 1966-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-05-05 | 1969-11-04 | 1970-05-06 | $7700.00 | Window Closed / Lapsed |