US3719351A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extruder for thermoplastic or non-cross-linked elastomeric material, a mixing zone defined by a feed screw
Assignee: Windmoeller and Hoelscher KG
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Filing: 1971-05-04
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Granted: 1973-03-06
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Expires: 1991-05-04
Abstract
Abstract In an extruder for thermoplastic or non-cross-linked elastomeric material, a mixing zone defined by a feed screw for the material comprises at least one mixing ring on a cylindrical core portion of the screw, the mixing ring being apertured for the flow of material through the ring. The apertures are formed by a plurality of circumferentially distributed passages which are alternately oppositely inclined to the longitudinal axis of the screw.
Inventors
- 👤 H Upmeier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:10
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/36; B29C48/50; B29C48/695; B29C48/70; B29C48/705; B29C48/362; B29C48/03
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
96 words
An extruder for thermoplastic or non-cross-linked elastomeric material, comprising a feed screw rotatable in a cylinder, the feed screw having a core which defines an annular flow gap with the wall of the cylinder, wherein the feed screw is provided with a mixing zone containing a mixing ring which extends from the core of the screw to the cylinder wall and which is provided with a plurality of apertures for the flow of material therethrough, the apertures being formed by oblique passages extending alternately from near the core to near the cylinder wall, and vice versa.
Claim 2
Dependent Claim
96 words
An extruder for thermoplastic or non-cross-linked elastomeric material, comprising a feed screw rotatable in a cylinder, the feed screw having a core which defines an annular flow gap with the wall of the cylinder, wherein the feed screw is provided with a mixing zone containing a mixing ring which extends from the core of the screw to the cylinder wall and which is provided with a plurality of apertures for the flow of material therethrough, the apertures being formed by oblique passages extending alternately from near the core to near the cylinder wall, and vice versa.
Claim 3
Dependent Claim
96 words
An extruder for thermoplastic or non-cross-linked elastomeric material, comprising a feed screw rotatable in a cylinder, the feed screw having a core which defines an annular flow gap with the wall of the cylinder, wherein the feed screw is provided with a mixing zone containing a mixing ring which extends from the core of the screw to the cylinder wall and which is provided with a plurality of apertures for the flow of material therethrough, the apertures being formed by oblique passages extending alternately from near the core to near the cylinder wall, and vice versa.
Claim 4
Dependent Claim
96 words
An extruder for thermoplastic or non-cross-linked elastomeric material, comprising a feed screw rotatable in a cylinder, the feed screw having a core which defines an annular flow gap with the wall of the cylinder, wherein the feed screw is provided with a mixing zone containing a mixing ring which extends from the core of the screw to the cylinder wall and which is provided with a plurality of apertures for the flow of material therethrough, the apertures being formed by oblique passages extending alternately from near the core to near the cylinder wall, and vice versa.
Claim 5
Dependent Claim
19 words
An extruder according to claim 1 comprising two or more such mixing rings at a spacing from one another.
Claim 6
Dependent Claim
62 words
An extruder according to claim 1, wherein the mixing zone is preceded, as viewed in the direction of flow of the material, by a feeding and shearing zone, the length and width of said annular flow gap in the mixing zone giving a volume which is at least equal to the total volume of the gap in the feeding and shearing zone.
Claim 7
Dependent Claim
24 words
An extruder according to claim 1, wherein the or each mixing ring is in the form of a replaceable disc on the feed screw.
Claim 8
Dependent Claim
30 words
An extruder accordiNg to claim 1, wherein the inlet ends of the passages are provided with inlet cavities which extend unilaterally in the direction of rotation of the feed screw.
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) | 1976-03-05 | 1976-09-04 | 1977-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-05 | 1980-09-04 | 1981-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-05 | 1984-09-04 | 1985-03-06 | $7700.00 | Window Closed / Lapsed |