US3877857A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiple melt chamber extrusion die
Assignee: Beloit Corp
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Filing: 1972-12-20
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Granted: 1975-04-15
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Expires: 1992-12-20
Abstract
Abstract Extrusion die for the extrusion and coextrusion of the plastic materials in which the die body is split and engages opposite sides of a center divider forming a die in which the thermoplastic materials can combine inside and outside of the die in accordance with the characteristics of the plastic materials in a fluid state in the individual melt chambers. The die has interchangeable lips and dividers to effect a combination of the melt streams in the die before exiting, or as they exit from the die, or after they have passed from the die to the atmosphere.
Inventors
- 👤 James J Melead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:47
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/30; B29C48/305; B29C48/31; B29C48/313; B29C48/03; B29C48/07; B29C48/08; B29C48/16; B29C48/18; B29C48/21; B29C48/255; B29C48/2556; B29C48/307
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
161 words
In a multiple melt chamber film extrusion die, an elongated die body split along its longitudinal center, and having two die halves, a center divider extending between said die halves, at least two melt chambers in said die body extending on each side of said center divider and opening to said divider, gap control members slidably guided along opposite sides of said center divider and having lips defining the inner walls of the innermost of said melt chambers adjacent said center divider, means for adjusting said gap control members to define exit passageways leading from said melt chambers of preselected widths in accordance with the thickness of the film to be extruded from said melt chamber, and die lips adjustably secured to said die body and cooperating with said center divider to define melt flow passageways leading from said melt chambers along each side of said divider, and to provide exit slots for the extrusion of dual films of plastic material.
Claim 2
Dependent Claim
161 words
In a multiple melt chamber film extrusion die, an elongated die body split along its longitudinal center, and having two die halves, a center divider extending between said die halves, at least two melt chambers in said die body extending on each side of said center divider and opening to said divider, gap control members slidably guided along opposite sides of said center divider and having lips defining the inner walls of the innermost of said melt chambers adjacent said center divider, means for adjusting said gap control members to define exit passageways leading from said melt chambers of preselected widths in accordance with the thickness of the film to be extruded from said melt chamber, and die lips adjustably secured to said die body and cooperating with said center divider to define melt flow passageways leading from said melt chambers along each side of said divider, and to provide exit slots for the extrusion of dual films of plastic material.
Claim 3
Dependent Claim
26 words
The multiple melt chamber film extrusion die of claim 1, including individual plastic melt inlet passageways leading into said melt flow chambers through the ends thereof.
Claim 4
Dependent Claim
49 words
The multiple melt chamber film extrusion die of claim 2, wherein the inlets are in the form of die plugs mounted at one end of said die, each die plug having at least two inlets leading thereinto for the extrusion of different plastic melt materials along said melt chambers.
Claim 5
Dependent Claim
37 words
The multiple melt chamber film extrusion die of claim 3, wherein the die plugs have converging vanes cooperating with said inlets to effect the extrusion of at least three layers of plastic material along each melt chamber.
Claim 6
Dependent Claim
25 words
The multiple melt chamber film extrusion die of claim 2, including individual plastic melt inlet passageways leading into said melt chambers intermediate the ends thereof.
Claim 7
Dependent Claim
30 words
The multiple melt chamber film extrusion die of claim 1, wherein the gap control lips are inclined lips and terminate at said center divider at obtuse angles with respect thereto.
Claim 8
Dependent Claim
46 words
The multiple melt chamber film extrusion die of claim 1, wherein the means varying the width of the exit passageways leading from said melt chambers comprise push-pull screws spaced along said die body and having adjustable cooperation with said gap control members for the length thereof.
Claim 9
Dependent Claim
59 words
The multiple melt chamber film extrusion die of claim 1, in which the center divider has a tapered lower end portion and the die lips are interchangeable and include die lips having inclined walls formed to converge to a rectilinear exit slot for the joining of a dual film of plastic material immediately upon exiting from the center divider.
Claim 10
Dependent Claim
41 words
The multiple melt chamber die of claim 1, wherein the center divider has a tapered discharge end, and wherein the die lips are interchangeable and include die lips having tapered walls conforming to said tapered discharge end of said center divider.
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) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |