US3870451A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for extruding foamed thermoplastic material
Assignee: Beloit Corp
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Filing: 1973-04-30
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Granted: 1975-03-11
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Expires: 1993-04-30
Abstract
Abstract An apparatus for continuously forming a foamed thermoplastic profile including an extruder having a die attached to the outlet end thereof. A rotatable screw is disposed within the extruder and a mandrel is secured to the downstream end of the screw. The screw extends towards the outlet of the die. The mandrel and die cooperatively define an annular outlet orifice to produce a tubular shaped parison. Adjacent to the annular outlet is a sizing apparatus to properly size and shape the tubular parison.
Inventors
- 👤 Cem M Gokcen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:58
CPC Classifications
B; B29; B29C; B29C44/00; B29C44/34; B29C44/36; B29C44/46; B29C44/468; B29C44/50; B29C44/507; B29C48/00; B29C48/25; B29C48/36; B29C48/50; B29C48/505; B29C48/51; B29C48/515; B29C48/78; B29C48/80; B29C48/83; B29C48/832; B29C48/84; B29C48/845; B29C48/85; B29C48/875; B29C48/92; B29C2948/00; B29C2948/92; B29C2948/92009; B29C2948/92209; B29C2948/92323; B29C2948/92361; B29C2948/92409; B29C2948/92504; B29C2948/92704; B29C2948/92819; B29C2948/92857; B29C2948/92904; B29C48/001; B29C48/0012; B29C48/03; B29C48/09; B29C48/10; B29C48/12; B29K; B29K2105/00; B29K2105/04; B29L; B29L2023/00; Y; Y10; Y10S; Y10S264/00; Y10S264/14
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
112 words
A structure for producing a foamed thermoplastic product comprising an extruder, a die structure attached to the outlet end of said extruder and in fluid communication therewith, a plasticizing screw rotatably disposed within said extruder, the improvement comprising: a mandrel secured to the downstream end of said screw to rotate therewith, said mandrel extending into and to the outlet end of said die structure and cooperating therewith to form an outlet orifice, said screw and mandrel defining a generally toroidal shaped melt flow passageway of substantially uniform thickness from the downstream end of the screw to the outlet of the die structure and having at least a portion of decreasing cross-sectional area.
Claim 2
Dependent Claim
112 words
A structure for producing a foamed thermoplastic product comprising an extruder, a die structure attached to the outlet end of said extruder and in fluid communication therewith, a plasticizing screw rotatably disposed within said extruder, the improvement comprising: a mandrel secured to the downstream end of said screw to rotate therewith, said mandrel extending into and to the outlet end of said die structure and cooperating therewith to form an outlet orifice, said screw and mandrel defining a generally toroidal shaped melt flow passageway of substantially uniform thickness from the downstream end of the screw to the outlet of the die structure and having at least a portion of decreasing cross-sectional area.
Claim 3
Dependent Claim
112 words
A structure for producing a foamed thermoplastic product comprising an extruder, a die structure attached to the outlet end of said extruder and in fluid communication therewith, a plasticizing screw rotatably disposed within said extruder, the improvement comprising: a mandrel secured to the downstream end of said screw to rotate therewith, said mandrel extending into and to the outlet end of said die structure and cooperating therewith to form an outlet orifice, said screw and mandrel defining a generally toroidal shaped melt flow passageway of substantially uniform thickness from the downstream end of the screw to the outlet of the die structure and having at least a portion of decreasing cross-sectional area.
Claim 4
Dependent Claim
112 words
A structure for producing a foamed thermoplastic product comprising an extruder, a die structure attached to the outlet end of said extruder and in fluid communication therewith, a plasticizing screw rotatably disposed within said extruder, the improvement comprising: a mandrel secured to the downstream end of said screw to rotate therewith, said mandrel extending into and to the outlet end of said die structure and cooperating therewith to form an outlet orifice, said screw and mandrel defining a generally toroidal shaped melt flow passageway of substantially uniform thickness from the downstream end of the screw to the outlet of the die structure and having at least a portion of decreasing cross-sectional area.
Claim 5
Dependent Claim
13 words
The structure recited in claim 1 wherein the outlet orifice is annularly shaped.
Claim 6
Dependent Claim
24 words
The structure recited in claim 1 wherein the mandrel is detachably secured to the screw and is attached to the screw within the extruder.
Claim 7
Dependent Claim
23 words
The structure recited in claim 1 and further including a sizing member, said sizing member being closely spaced adjacent to the outlet orifice.
Claim 8
Dependent Claim
31 words
The structure recited in claim 4 wherein any foamed thermoplastic material leaving the outlet orifice is of tubular shape and is converted to a different polygonal shape within the sizing member.
Claim 9
Dependent Claim
49 words
The structure recited in claim 1 wherein said screw has an opening disposed therein and said mandrel has a corresponding opening disposed therein in fluid communication with said screw opening, and means to heat and cool said openings to regulate the temperature of the downstream portion of the mandrel.
Claim 10
Dependent Claim
50 words
The structure recited in claim 6 wherein the heating and cooling means comprise an outer conduit disposed in said openings, and an inner conduit disposed within said outer conduit, and means supplying heating and cooling fluid to one of said conduits and returning the fluid in the other said conduits.
References Cited (Backward Citations)
US2653348A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |