US3767346A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Film extrusion die
Assignee: FMC Corp
•
Filing: 1971-07-22
•
Granted: 1973-10-23
•
Expires: 1991-07-22
Abstract
Abstract An extrusion die including a pair of lips which together serve to shape a molten thermoplastic polymeric material into a film, with a comparatively short heat exchanger movably mounted on one of such lips for use in selectively varying the temperature at localized areas thereof.
Inventors
- 👤 J Mihalik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:00
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/88; B29C48/911; B29C48/9135; B29C48/914; B29C48/03; B29C48/07; B29C48/08; B29C48/30; B29C48/305; B29C48/31; B29C48/32; B29C48/78; B29C48/86; B29C48/865; B29C48/87; B29C48/09; B29C48/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
131 words
A film extrusion die which includes a pair of die lips positioned with opposing surfaces thereof in spaced apart relationship to together define an extrusion opening, means for delivering a molten thermoplastic polymeric material under pressure inbetween said die lips for extrusion as a film from said extrusion opening, and a heat exchanger slidably mounted on one of said die lips for selective adjustment relative to said one die lip along a path which is substantially parallel to but spaced from said extrusion opening, said heat exchanger being of such size as to contact with only a fractional portion of such one die lip in each of the positions to which it is adjusted to thereby facilitate variation in the temperature of said one die lip At only localized areas thereof.
Claim 2
Dependent Claim
131 words
A film extrusion die which includes a pair of die lips positioned with opposing surfaces thereof in spaced apart relationship to together define an extrusion opening, means for delivering a molten thermoplastic polymeric material under pressure inbetween said die lips for extrusion as a film from said extrusion opening, and a heat exchanger slidably mounted on one of said die lips for selective adjustment relative to said one die lip along a path which is substantially parallel to but spaced from said extrusion opening, said heat exchanger being of such size as to contact with only a fractional portion of such one die lip in each of the positions to which it is adjusted to thereby facilitate variation in the temperature of said one die lip At only localized areas thereof.
Claim 3
Dependent Claim
36 words
A film extrusion die as defined in claim 1 wherein a plurality of separate heat exchangers are slidably mounted on said one die lip for independent sliding adjustment into different positions relative to said extrusion opening.
Claim 4
Dependent Claim
42 words
A film extrusion die as defined in claim 1 wherein at least one heat exchanger is slidably mounted on the other of said die lips for selective adjustment along a path which is substantially parallel to but spaced from said extrusion opening.
Claim 5
Dependent Claim
28 words
A film extrusion die as defined in claim 1 wherein said heat exchanger includes a closed tube and means for circulating a heat exchange medium through such tube.
Claim 6
Dependent Claim
47 words
A film extrusion die as defined in claim 4 wherein said one die lip includes a continuous slot formed in a surface thereof remote from said opposing surfaces, said slot shaped to slidably receive said heat exchanger and having undercut portions to retain said heat exchanger therein.
Claim 7
Dependent Claim
21 words
A film extrusion die as defined in claim 5 wherein said die lips are annular for use in forming tubular films.
Claim 8
Dependent Claim
21 words
A film extrusion die as defined in claim 5 wherein said die lips are elongated for use in forming flat films.
References Cited (Backward Citations)
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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) | 1976-10-22 | 1977-04-23 | 1977-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-22 | 1981-04-23 | 1981-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-22 | 1985-04-23 | 1985-10-23 | $7700.00 | Window Closed / Lapsed |