US4421465A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus providing uniform resin distribution in a coextruded product
Assignee: Mobil Oil AS
•
Filing: 1982-03-18
•
Granted: 1983-12-20
•
Expires: 2002-03-18
Abstract
Abstract Disclosed is a method and apparatus for ensuring uniform distribution of higher and lower viscosity or flow rate resins in a product produced by a coextrusion process. A flow restriction is provided in the flow path of the lower viscosity or flow rate resin to increase the pressure drop of this resin as it passes through a coextrusion die. The increased pressure drop introduced by the flow restriction causes the lower viscosity or flow rate resin to be more uniformly distributed in the extruded product. A specific die construction providing a uniform resin flow channel within the die is also described.
Inventors
- 👤 Fox J. Herrington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 18:18
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/36; B29C48/50; B29C48/695; B29C48/70; B29C48/03; B29C48/09; B29C48/10; B29C48/16; B29C48/18; B29C48/21; B29C48/30; B29C48/32; B29C48/335; B29C48/337; B29C48/338; B29C48/34; B29C48/92; B29C2948/00; B29C2948/92; B29C2948/92504; B29C2948/92514; B29C2948/9258; B29C2948/926; B29C2948/92695; B29C2948/9279
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
182 words
A die for coextruding first and second molten streams of resin comprising: a first flow channel for one of said resin streams, a second flow channel for the other of said resin streams, said first and second channels terminating in a molten resin junction region, and a flow channel coupling said junction region to an extrusion orifice, at least one of said first and second flow channels being defined by first and second opposing die surfaces, each respectively provided on first and second die members, said first and second die members engaging with one another at respective planar engaging faces, the planar engaging face of said first die member being offset from and in parallel with at least a portion of the opposing die surface of said first die member and the planar engaging face of second die member being in parallel with at least a portion of the opposing die surface of said second die member said offset defining the gap size of said at least one flow channel and said parallel arrangement insuring no significant gap error in said channel.
Claim 2
Dependent Claim
182 words
A die for coextruding first and second molten streams of resin comprising: a first flow channel for one of said resin streams, a second flow channel for the other of said resin streams, said first and second channels terminating in a molten resin junction region, and a flow channel coupling said junction region to an extrusion orifice, at least one of said first and second flow channels being defined by first and second opposing die surfaces, each respectively provided on first and second die members, said first and second die members engaging with one another at respective planar engaging faces, the planar engaging face of said first die member being offset from and in parallel with at least a portion of the opposing die surface of said first die member and the planar engaging face of second die member being in parallel with at least a portion of the opposing die surface of said second die member said offset defining the gap size of said at least one flow channel and said parallel arrangement insuring no significant gap error in said channel.
References Cited (Backward Citations)
US2141776A
Cited
US2859476A
Cited
US2978748A
Cited
US3308508A
Cited
US3365750A
Cited
US3669591A
Cited
DE1966876A1
Cited
US3611492A
Cited
US4091064A
Cited
US4061461A
Cited
US4125585A
Cited
US4208175A
Cited
US4249875A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-19 | 1987-06-20 | 1987-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-19 | 1991-06-20 | 1991-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-19 | 1995-06-20 | 1995-12-20 | $7700.00 | Window Closed / Lapsed |