US3924841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extrusion moulding machine
Assignee: Individual
•
Filing: 1973-11-30
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Granted: 1975-12-09
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Expires: 1993-11-30
Abstract
Abstract An extrusion moulding machine comprising a cylindrical housing having input and output ports and a tapered feed screw mounted within the cylindrical housing and rotatably supported at each end. The feed screw tapers from the input port to the output port of the cylindrical housing. Furthermore, the feed screw comprises two counter-rotating helical threads meeting at the output port.
Inventors
- 👤 Jitsumi Shinmoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 02:05
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/36; B29C48/395; B29C48/455; B29C48/50; B29C48/03
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
209 words
An extruder having an input port and an output port for the mixing and extrusion of plastics, comprising: a housing defining a cylindrical cavity therein; a tapered feed screw having first and second ends, said feed screw further having a first helical threading on a portion thereof, said tapered feed screw being positioNed within said cylindrical cavity with each end being supported by bearings, said first end having a smaller root diameter and located adjacent said input port and said second end having a larger root diameter and located adjacent said output port; a mixing surface formed on said feed screw adjacent to said first helical threading and positioned adjacent to said output port; and a threaded sealing surface formed on said feed screw adjacent to said mixing surface near said outlet port such that said mixing surface is located on said feed screw between said first helical threading and said threaded sealing surface, said threaded sealing surface being a second helical threading opposite in inclination to said first helical threading, whereby said threaded sealing surface tends to prevent the further progress of said plastic along said housing as said tapered feed screw forces said plastic to be extruded out of said output port adjacent to said mixing surface.
Claim 2
Dependent Claim
209 words
An extruder having an input port and an output port for the mixing and extrusion of plastics, comprising: a housing defining a cylindrical cavity therein; a tapered feed screw having first and second ends, said feed screw further having a first helical threading on a portion thereof, said tapered feed screw being positioNed within said cylindrical cavity with each end being supported by bearings, said first end having a smaller root diameter and located adjacent said input port and said second end having a larger root diameter and located adjacent said output port; a mixing surface formed on said feed screw adjacent to said first helical threading and positioned adjacent to said output port; and a threaded sealing surface formed on said feed screw adjacent to said mixing surface near said outlet port such that said mixing surface is located on said feed screw between said first helical threading and said threaded sealing surface, said threaded sealing surface being a second helical threading opposite in inclination to said first helical threading, whereby said threaded sealing surface tends to prevent the further progress of said plastic along said housing as said tapered feed screw forces said plastic to be extruded out of said output port adjacent to said mixing surface.
Claim 3
Dependent Claim
49 words
The extruder of claim 1 wherein said feed screw has a single taper and is retained within said housing by a thrust bearing, whereby the stress on said feed screw is transmitted as a tensive rather than a compressive stress parallel to the longitudinal axis of said feed screw.
Claim 4
Dependent Claim
21 words
The extruder of claim 1 wherein: said tapered feed screw is rotatably driven at said end having said larger root diameter.
Claim 5
Dependent Claim
26 words
The extruder of claim 1 wherein: said feed screw defines a longitudinal cavity therein for the insertion of a means for injecting a heat exchanging fluid.
Claim 6
Dependent Claim
159 words
An extruder having an input port and an output port for the mixing and extrusion of plastics, comprising: a housing defining a cylindrical cavity therein; a tapered feed screw having two ends and a first helical threading on a portion thereof, said tapered feed screw being positioned within said cylindrical cavity, said feed screw having a longitudinal cavity therein for the insertion of a means for sensing temperature; a mixing surface formed on said feed screw adjacent to said first helical threading and positioned adjacent to said output port; and a threaded sealing surface formed on said feed screw adjacent to said mixing surface, said threaded sealing surface being a second helical threading opposite in inclination to said first helical threading, whereby said threaded sealing surface tends to prevent the further progress of said plastic along said housing as said tapered feed screw forces said plastic to be extruded out of said output port adjacent to said mixing surface.
Claim 7
Dependent Claim
159 words
An extruder having an input port and an output port for the mixing and extrusion of plastics, comprising: a housing defining a cylindrical cavity therein; a tapered feed screw having two ends and a first helical threading on a portion thereof, said tapered feed screw being positioned within said cylindrical cavity, said feed screw having a longitudinal cavity therein for the insertion of a means for sensing temperature; a mixing surface formed on said feed screw adjacent to said first helical threading and positioned adjacent to said output port; and a threaded sealing surface formed on said feed screw adjacent to said mixing surface, said threaded sealing surface being a second helical threading opposite in inclination to said first helical threading, whereby said threaded sealing surface tends to prevent the further progress of said plastic along said housing as said tapered feed screw forces said plastic to be extruded out of said output port adjacent to said mixing surface.
Claim 8
Dependent Claim
62 words
The extruder of claim 5 further comprising: a mixing surface formed on said feed screw between each of said sealing surfaces and said adjacent first helical threadings, said mixing surface being in the proximity of one of said output ports; and a driving means for rotating said feed screw, said driving means coupled to each of said ends of said feed screw.
Claim 9
Dependent Claim
186 words
An extruder having a central input port and two output ports for the extrusion of plastic, comprising: a housing defining a central cavity therein; a feed screw having first and second ends and being positioned within said cavity, said feed screw tapered toward its center and having two first helical threadings thereon of opposite inclination whereby said plastic introduced through said central input port is encouraged through said central input port toward each of said ends of said feed screw and is extruded out of said output ports, said first and second ends being supported by bearings whereby stress on each half of said feed screw is equally and oppositely directed so as to be substantially eliminated, said feed screw defining a longitudinal cavity therein for the insertion of a means for sensing temperature; and a threaded sealing surface at each of said ends of said feed screw, said sealing surface being a second helical threading oppositely inclined as compared to said adjacent first helical threading, said threaded sealing surface positioned between said bearings retaining said feed screw in said housing and an adjacent output port.
Claim 10
Dependent Claim
186 words
An extruder having a central input port and two output ports for the extrusion of plastic, comprising: a housing defining a central cavity therein; a feed screw having first and second ends and being positioned within said cavity, said feed screw tapered toward its center and having two first helical threadings thereon of opposite inclination whereby said plastic introduced through said central input port is encouraged through said central input port toward each of said ends of said feed screw and is extruded out of said output ports, said first and second ends being supported by bearings whereby stress on each half of said feed screw is equally and oppositely directed so as to be substantially eliminated, said feed screw defining a longitudinal cavity therein for the insertion of a means for sensing temperature; and a threaded sealing surface at each of said ends of said feed screw, said sealing surface being a second helical threading oppositely inclined as compared to said adjacent first helical threading, said threaded sealing surface positioned between said bearings retaining said feed screw in said housing and an adjacent output port.
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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) | 1978-12-08 | 1979-06-09 | 1979-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-08 | 1983-06-09 | 1983-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-08 | 1987-06-09 | 1987-12-09 | $7700.00 | Window Closed / Lapsed |