US4470942A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and equipment to obtain a plate provided with holes directly by extruding plastic materials
Assignee: RDB Plastotecnica SpA
•
Filing: 1982-03-12
•
Granted: 1984-09-11
•
Expires: 2002-03-12
Abstract
Abstract The invention relates to a process and an equipment to obtain a plate provided with holes directly by extruding plastic materials. The process consists in submitting the material coming out of an extruder head to expansion stresses according to more than one direction and in executing a plurality of perforations in said material submitted to expansion by means of perforating means; the equipment consists of a plurality of perforating devices provided with a reciprocating motion so that they can reach an interference position with respect to the material coming out of the extruder head and of means which, acting at the same time as the perforating devices, are suitable to produce an expansion of the extruded material.
Inventors
- 👤 Mario Beretta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:43
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/30; B29C48/301; B29C48/03; B29C48/09; B29C48/13; B29L; B29L2028/00; Y; Y10; Y10S; Y10S264/00; Y10S264/81
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
109 words
A process of manufacturing a plastic plate provided with holes, comprising the steps of effecting extrusion from an orifice of a plastic containing a multiplicity of fibers, said plastic being in a semifluid condition, biaxially expanding said plastic after said extrusion in a zone of expansion downstream of said orifice, bringing a plurality of perforating devices into contact with said plastic as expanded in said expansion zone at locations each of which is sufficiently spaced apart from said orifice that said fibers are separated without being cut, thereby forming a plurality of perforations in said plastic, further expanding said perforated plastic, and immersing said expanded plastic in a coolant.
Claim 2
Dependent Claim
109 words
A process of manufacturing a plastic plate provided with holes, comprising the steps of effecting extrusion from an orifice of a plastic containing a multiplicity of fibers, said plastic being in a semifluid condition, biaxially expanding said plastic after said extrusion in a zone of expansion downstream of said orifice, bringing a plurality of perforating devices into contact with said plastic as expanded in said expansion zone at locations each of which is sufficiently spaced apart from said orifice that said fibers are separated without being cut, thereby forming a plurality of perforations in said plastic, further expanding said perforated plastic, and immersing said expanded plastic in a coolant.
Claim 3
Dependent Claim
133 words
Apparatus for manufacturing a plastic plate provided with holes, comprising an extruder head having an orifice for extruding plastic containing a multiplicity of fibers, said plastic being in a semifluid condition, mandrel means mounted in spaced-apart relation to said extruder head for biaxially expanding said extruded plastic in a zone of expansion downstream of said orifice, a plurality of perforating devices periodically movable into contact with said plastic as expanded at a plurality of locations between said extruder head and said mandrel means, each location being sufficiently spaced apart from said orifice that said fibers are separated without being cut, thereby forming a plurality of perforations in said plastic, said mandrel means facilitating further expansion of said plastic after the formation of said perforations, and means for cooling said perforated and expanded plastic.
Claim 4
Dependent Claim
133 words
Apparatus for manufacturing a plastic plate provided with holes, comprising an extruder head having an orifice for extruding plastic containing a multiplicity of fibers, said plastic being in a semifluid condition, mandrel means mounted in spaced-apart relation to said extruder head for biaxially expanding said extruded plastic in a zone of expansion downstream of said orifice, a plurality of perforating devices periodically movable into contact with said plastic as expanded at a plurality of locations between said extruder head and said mandrel means, each location being sufficiently spaced apart from said orifice that said fibers are separated without being cut, thereby forming a plurality of perforations in said plastic, said mandrel means facilitating further expansion of said plastic after the formation of said perforations, and means for cooling said perforated and expanded plastic.
Claim 5
Dependent Claim
61 words
Apparatus according to claim 2 wherein said extruder head is formed with an extrusion orifice that is circular in cross section, said mandrel means is circular in cross section, said extrusion orifice and said mandrel means are mounted coaxially with respect to each other, and the cross section of said mandrel means being larger than the cross section of said orifice.
Claim 6
Dependent Claim
29 words
Apparatus according to claim 2 wherein said perforating devices have a direction of movement within the range of (a) vertical to (b) perpendicular to the surface of said plastic.
Claim 7
Dependent Claim
19 words
Apparatus according to claim 2 or 3 wherein said perforating devices are disposed in a circle around said plastic.
Claim 8
Dependent Claim
35 words
Apparatus according to claim 5 wherein said perforating devices further have a circular direction of movement around said plastic, said movement around said plastic being within the range of (a) continuous movement to stepped movement.
References Cited (Backward Citations)
US3329998A
Cited
US3160687A
Cited
US3642967A
Cited
US3714310A
Cited
FR2131842A6
Cited
FR2138198A2
Cited
FR2160270A1
Cited
US3841815A
Cited
DE2349213A1
Cited
US3947174A
Cited
US4038008A
Cited
US4303609A
Cited
US4189292A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-09-11 | 1988-03-12 | 1988-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-11 | 1992-03-12 | 1992-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-11 | 1996-03-12 | 1996-09-11 | $7700.00 | Window Closed / Lapsed |