US4324748A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and apparatus for extruding plastic foams through a fluorocarbon lined die shaping means having extended wear characteristics
Assignee: JAPAN STYRENE PAPER Corp A CORP OF JAPAN
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Filing: 1980-09-22
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Granted: 1982-04-13
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Expires: 2000-09-22
Abstract
Abstract In a method for producing a plastic foam of a desired expanded dimension which is constituted by extruding a melt of a thermoplastic synthetic resin containing a blowing agent through a die of an extruder and passing the extrudate through a shaping device located outwardly of the extruder and secured to the discharge end of the extruder while expanding and solidifying the molten mass so that it fills the shaping device; the improvement wherein at least a part of that area of the inside surface of the shaping device with which the expanded resin makes contact is formed of a plate of a fluorocarbon resin, said plate being secured to the inside surface of the shaping device by fitting portions, said fitting portions having a sufficient space for absorbing an increase in the volume of the fluorocarbon resin plate at the temperature of extrusion molding; and an apparatus for use in the above described process.
Inventors
- 👤 Hideo Hatakeyama
- 👤 Toru Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:30
CPC Classifications
B; B29; B29C; B29C44/00; B29C44/34; B29C44/60; B29C44/605; B29C44/36; B29C44/46; B29C44/50; B29C44/505; B29C48/00; B29C48/03; B29C48/07; B29C33/00; B29C33/38; B29C33/40; B29K; B29K2827/00; B29K2827/12; B29K2827/18; Y; Y10; Y10S; Y10S425/00; Y10S425/055; Y10S425/115
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
188 words
In a method for producing plastic foam by extruding a melt of a thermoplastic synthetic resin containing a blowing agent through an extrusion die on the end of an extruder, and forming and solidifying it by passing it through a shaping device having a metallic body secured to the discharge end of the extruder and extending away from said die in the direction of extrusion on the extruder opening into the inlet of the shaping device, the improvement comprising providing a plate of a fluorocarbon resin on at least a part of the inside surfaces of the metallic body, one of said body and said plate having recesses therein and the other of said body and said plate having projections thereon interfitted with said recesses, the inner surfaces of said recesses and the exterior surfaces of said projections being spaced from each other when the plate is unheated, said spaces being sufficiently large to just accommodate the resin plate at the temperature of extrusion from the heat of the resin for causing said projections to fit in said recesses for holding said plate securely on said shaping device.
Claim 2
Dependent Claim
188 words
In a method for producing plastic foam by extruding a melt of a thermoplastic synthetic resin containing a blowing agent through an extrusion die on the end of an extruder, and forming and solidifying it by passing it through a shaping device having a metallic body secured to the discharge end of the extruder and extending away from said die in the direction of extrusion on the extruder opening into the inlet of the shaping device, the improvement comprising providing a plate of a fluorocarbon resin on at least a part of the inside surfaces of the metallic body, one of said body and said plate having recesses therein and the other of said body and said plate having projections thereon interfitted with said recesses, the inner surfaces of said recesses and the exterior surfaces of said projections being spaced from each other when the plate is unheated, said spaces being sufficiently large to just accommodate the resin plate at the temperature of extrusion from the heat of the resin for causing said projections to fit in said recesses for holding said plate securely on said shaping device.
Claim 3
Independent Claim
190 words
An apparatus for producing a plastic foam by extruding a melt of a thermoplastic synthetic resin containing a blowing agent and foaming and solidifying it, said apparatus comprising an extruder having a discharge end with an extrusion die thereat, a shaping device secured to the discharge end of the extruder and extending away from said die in the direction of extrusion, said die on the extruder opening into the inlet of the shaping device, said shaping device having a metallic body and a plate of a fluorocarbon resin on at least a part of the inside surfaces of the metallic body, one of said body and said plate having recesses therein and the other of said body and said plate having projections thereon interfitted with said recesses, the inner surfaces of said recesses and the exterior surfaces of said projections being spaced from each other when the plate is unheated, said spaces being sufficiently large to just accommodate the resin plate at the temperature of extrusion molding, whereby when said plate is heated during extrusion said projections fit in said recesses for holding said plate securely on said shaping device.
Claim 4
Independent Claim
190 words
An apparatus for producing a plastic foam by extruding a melt of a thermoplastic synthetic resin containing a blowing agent and foaming and solidifying it, said apparatus comprising an extruder having a discharge end with an extrusion die thereat, a shaping device secured to the discharge end of the extruder and extending away from said die in the direction of extrusion, said die on the extruder opening into the inlet of the shaping device, said shaping device having a metallic body and a plate of a fluorocarbon resin on at least a part of the inside surfaces of the metallic body, one of said body and said plate having recesses therein and the other of said body and said plate having projections thereon interfitted with said recesses, the inner surfaces of said recesses and the exterior surfaces of said projections being spaced from each other when the plate is unheated, said spaces being sufficiently large to just accommodate the resin plate at the temperature of extrusion molding, whereby when said plate is heated during extrusion said projections fit in said recesses for holding said plate securely on said shaping device.
Claim 5
Dependent Claim
30 words
The apparatus as claimed in claim 2 wherein said projections are provided on the inside surfaces of the metallic body, and said recesses are provided on the fluorocarbon resin plate.
Claim 6
Dependent Claim
30 words
The apparatus as claimed in claim 2 wherein said recesses are provided on the inside surfaces of the metallic body, and said projections are provided on the fluorocarbon resin plate.
Claim 7
Dependent Claim
28 words
The apparatus as claimed in claim 3 or 4 wherein the projections are rail-like projections extending continuously at right angles to the lengthwise direction of the shaping device.
Claim 8
Dependent Claim
14 words
The apparatus as claimed in claim 3 or 4 wherein the projections are discontinuous.
Claim 9
Dependent Claim
15 words
The apparatus as claimed in claim 3 or 4 wherein the recesses are continuous grooves.
Claim 10
Dependent Claim
31 words
The apparatus as claimed in claim 3 or 4 wherein the recesses have a shape suitable for receiving the corresponding projections, and are individually provided at points opposed to the projections.
Claim 11
Dependent Claim
50 words
The apparatus as claimed in claim 3 wherein said recesses are grooves and said projections are stops, said other said body and said plate having grooves therein opposed to said firstmentioned grooves and in which said stops are positioned, said stops having the other ends interfitted in said firstmentioned grooves.
Claim 12
Dependent Claim
31 words
The apparatus as claimed in claim 3 wherein the spacing between the projections and the recesses when the plate is unheated gradually increases toward the discharge end of the shaping device.
Claim 13
Dependent Claim
35 words
The apparatus as claimed in claim 3 wherein the fluorocarbon resin plate extends beyond the discharge end of the shaping device for being located close to a pair of take-up rolls outside the shaping device.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-04-12 | 1985-10-12 | 1986-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-04-12 | 1989-10-12 | 1990-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-04-12 | 1993-10-12 | 1994-04-13 | $7700.00 | Window Closed / Lapsed |