US4701116A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extrusion die for a blow head for making blown plastic films
Assignee: Windmoeller and Hoelscher KG
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Filing: 1985-09-27
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Granted: 1987-10-20
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Expires: 2005-09-27
Abstract
Abstract An extrusion die for a blow head for making blown plastic films comprises inner and outer rings, which are made of a ferrous material, particularly steel, and define between them an annular orifice. Those surfaces of the inner and outer rings which define the die orifice are covered by a layer consisting of a metallic material having a higher thermal conductivity than steel.
Inventors
- 👤 Fritz Achelpohl
- 👤 Gerhard Winkler
- 👤 Hermann Tupker
- 👤 Jurgen Linkies
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:05
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/30; B29C48/32; B29C48/03; B29C48/09; B29C48/10; B29K; B29K2705/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
76 words
An extrusion die for a blow head for making blown plastic films comprising inner and outer rings, which are made of steel, and define between them an annular orifice, characterized in that the entire surfaces of the inner and outer rings which define the die orifice are covered by a layer consisting of a metallic material having a thermal conductivity of about 0.7 cal/(cm×s×degree) to obtain a uniform temperature profile in both axial and peripheral directions.
Claim 2
Dependent Claim
76 words
An extrusion die for a blow head for making blown plastic films comprising inner and outer rings, which are made of steel, and define between them an annular orifice, characterized in that the entire surfaces of the inner and outer rings which define the die orifice are covered by a layer consisting of a metallic material having a thermal conductivity of about 0.7 cal/(cm×s×degree) to obtain a uniform temperature profile in both axial and peripheral directions.
Claim 3
Dependent Claim
16 words
An extrusion die according to claim 1, characterized in that each layer consists of a bushing.
Claim 4
Dependent Claim
24 words
An extrusion die according to claim 2, characterized in that a heat-insulating layer is provided between the bushings and the inner and outer rings.
Claim 5
Dependent Claim
28 words
An extrusion die according to claim 1, characterized in that the layer consists of a sprayed or centrifugally applied coating having a thickness of at least 0.2 mm.
Claim 6
Dependent Claim
31 words
An extrusion die according to claim 1, whereby the inner and outer rings are formed with grooves, which define chambers, which are connected to lines for conducting cooling or heating fluids.
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) | 1990-10-19 | 1991-04-20 | 1991-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-19 | 1995-04-20 | 1995-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-19 | 1999-04-20 | 1999-10-20 | $7700.00 | Window Closed / Lapsed |