US3705779A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for manufacturing a plastic tube with transverse grooves
Assignee: Wavin BV
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Filing: 1970-12-21
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Granted: 1972-12-12
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Expires: 1990-12-21
Abstract
Abstract A device for continuously manufacturing a plastic tube with helical grooves comprising an extruder with an annular nozzle situated between a casing and a core, and two rows of mould halves, each row being movable along endless guide paths extending parallel to each other in an operative track, opposite mould halves in this track completing one the other by their mould cavities so as to form a hollow mould, the core of the annular nozzle being provided with a continuous bore for introducing a gaseous pressure between the annular nozzle and closing means consisting of a number of discs of flexible material, whereby the discs have a diameter such that helical grooves are closed when a plastic tube is provided with grooves in the moulds.
Inventors
- 👤 Cornelis Van Zon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:32
CPC Classifications
B; B29; B29C; B29C49/00; B29C49/0015; B29C49/0021; B29C2791/00; B29C2791/004; B29C2791/006; B29C48/00; B29C48/001; B29C48/03; B29C48/09; B29C48/12; B29C48/13; B29L; B29L2023/00; B29L2023/003
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
237 words
In a device for manufacturing a plastic tube with transverse grooves, said device including an extruder having an annular nozzle situated between a casing and a core, mould halves directly adjoining each other, each mould half having a substantially semicylindrical mould cavity provided with a ribbed profile having wave valleys and wave tops, said mould halves being movable along endless guide paths having portions extending parallel to each other in an operative track, the opposite mould halves completing one the other by their partial mould cavities so as to form an elongated substantially cylindrical hollow mould cavity, and closing means retained within said cylindrical mould cavity in spaced relationship from the core, the core of the annular nozzle being provided with a bore for introducing a gaseous pressure medium between the annular nozzle and the closing means, comprising the improvement wherein the mould halves are provided with a helically extending rib profile to form a helical groove in said plastic tube, and the closing means including seal means having an outer diameter at least equal to the diameter of the cylinder formed by the bottoms of the valleys of the helical rib profile in the mould halves minus the wall thickness of the grooved tube formed within the cylindrical mould cavity, said seal means extending into and completely closing the helical groove within said tube to prevent the gaseous pressure medium from escaping past said closing means.
Claim 2
Dependent Claim
237 words
In a device for manufacturing a plastic tube with transverse grooves, said device including an extruder having an annular nozzle situated between a casing and a core, mould halves directly adjoining each other, each mould half having a substantially semicylindrical mould cavity provided with a ribbed profile having wave valleys and wave tops, said mould halves being movable along endless guide paths having portions extending parallel to each other in an operative track, the opposite mould halves completing one the other by their partial mould cavities so as to form an elongated substantially cylindrical hollow mould cavity, and closing means retained within said cylindrical mould cavity in spaced relationship from the core, the core of the annular nozzle being provided with a bore for introducing a gaseous pressure medium between the annular nozzle and the closing means, comprising the improvement wherein the mould halves are provided with a helically extending rib profile to form a helical groove in said plastic tube, and the closing means including seal means having an outer diameter at least equal to the diameter of the cylinder formed by the bottoms of the valleys of the helical rib profile in the mould halves minus the wall thickness of the grooved tube formed within the cylindrical mould cavity, said seal means extending into and completely closing the helical groove within said tube to prevent the gaseous pressure medium from escaping past said closing means.
Claim 3
Dependent Claim
17 words
A device according to claim 1, wherein said seal means is constructed of an elastically deformable material.
Claim 4
Dependent Claim
25 words
A device according to claim 2, wherein the deformable material has a helical profile corresponding to the helical rib profile formed in the mould halves.
Claim 5
Dependent Claim
16 words
A device according to claim 2, wherein said seal means is constructed of rubber or plastic.
Claim 6
Dependent Claim
44 words
A device according to claim 1, wherein said closing means comprises a plurality of metal plates having a diameter substantially equal to the diameter of the core, and said seal means including at least one disk of deformable material retained between said metal plates.
Claim 7
Dependent Claim
80 words
A device according to claim 1, wherein said closing means is disposed adjacent one end of the parallel portions of said guide path, and said nozzle is disposed adjacent the other end of said parallel portions of said guide path, said closing means being disposed outwardly of the track defined by said parallel portions of said guide path, and positioned for sealing engagement with the tube at a location wherein the tube is no longer contacted by the mould halves.
Claim 8
Dependent Claim
34 words
A device according to claim 1, further including cylindrical plug means positioned within the tube formed by said mould halves, said cylindrical plug means being disposed axially between said closing means and said nozzle.
Claim 9
Dependent Claim
37 words
A device according to claim 7, wherein at least one of said closing means and said plug means is axially displaceable along a hollow rod which extends axially of said tube and is interconnected to said core.
Claim 10
Dependent Claim
19 words
A device according to claim 7, wherein said cylindrical plug means is provided with a plurality of longitudinal bores.
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) | 1975-12-12 | 1976-06-12 | 1976-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-12 | 1980-06-12 | 1980-12-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-12 | 1984-06-12 | 1984-12-12 | $7700.00 | Window Closed / Lapsed |