US4666649A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for extruding thermoplastic resin
Assignee: Idemitsu Kosan Co Ltd
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Filing: 1985-12-16
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Granted: 1987-05-19
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Expires: 2005-12-16
Abstract
Abstract A method of extruding thermoplastic resin by use of an extruder, wherein the thermoplastic resin is continuously passed through a compression moderating type resin feeding-melting section, a resin flow disturbing section and a resin stress relaxing section, and extruded through a die. In an apparatus for working this method, a helical screw of the extruder is provided with the resin feeding-melting section, the resin flow disturbing section and a transfer section for relaxing the resin stress.
Inventors
- 👤 Toyokazu Takubo
- 👤 Atsushi Fujii
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:27
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/36; B29C48/50; B29C48/505; B29C48/67; B29C48/395; B29C48/001; B29C48/0017; B29C48/03; B29C48/07; B29C48/08; B29K; B29K2023/00; B29K2025/00; B29K2069/00; B29L; B29L2007/00; B29L2007/008
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
80 words
A method of extruding thermoplastic resin in a transparent condition through an extruder including a screw and a cylinder, the steps of said method comprising: passing said thermoplastic resin through a feeding-melting section having a compression ratio of 0.5-2; passing said resin through a resin flow disturbing section selected by any one of a torpedo, a Dulmage and a ring valve; and thereafter passing said resin through a stress relaxing section including a helical screw having a compression ratio 0.5-2.
Claim 2
Independent Claim
80 words
A method of extruding thermoplastic resin in a transparent condition through an extruder including a screw and a cylinder, the steps of said method comprising: passing said thermoplastic resin through a feeding-melting section having a compression ratio of 0.5-2; passing said resin through a resin flow disturbing section selected by any one of a torpedo, a Dulmage and a ring valve; and thereafter passing said resin through a stress relaxing section including a helical screw having a compression ratio 0.5-2.
Claim 3
Dependent Claim
26 words
A method of extruding thermoplastic resin as set forth in claim 1, wherein said thermoplastic resin is one of polypropylene, linear low-density polyethylene, polycarbonate and polystyrene.
Claim 4
Dependent Claim
33 words
A method of extruding thermoplastic resin as set forth in claim 1, wherein said resin flow disturbing section is a combination of a mechanism on said screw with a cylinder inner wall construction.
Claim 5
Dependent Claim
30 words
A method of extruding thermoplastic resin as set forth in claim 1, wherein the sectional length of said resin stress relaxing section is 4-15 times the diameter of said cylinder.
Claim 6
Dependent Claim
29 words
A method for extruding thermoplastic resin as set forth in claim 1, wherein the length of said resin flow disturbing section is 0.1-3 times the diameter of said cylinder.
Claim 7
Independent Claim
92 words
An apparatus for extruding thermoplastic resin in a transparent condition, comprising: a screw and a cylinder therefor, said screw including: a resin feed-melting secton comprising a helical screw having a compression ratio of 0.5-2; a resin flow disturbing section axially following said feed-melting section, selected by any one of a torpedo, a Dulmage and a ring valve; a transfer section axially following said flow disturbing section, comprising a helical screw having a compression ratio of 0.5-2; and a die for extruding said resin transferred from said transfer section in a predetermined shape.
Claim 8
Independent Claim
92 words
An apparatus for extruding thermoplastic resin in a transparent condition, comprising: a screw and a cylinder therefor, said screw including: a resin feed-melting secton comprising a helical screw having a compression ratio of 0.5-2; a resin flow disturbing section axially following said feed-melting section, selected by any one of a torpedo, a Dulmage and a ring valve; a transfer section axially following said flow disturbing section, comprising a helical screw having a compression ratio of 0.5-2; and a die for extruding said resin transferred from said transfer section in a predetermined shape.
Claim 9
Dependent Claim
38 words
An apparatus for extruding thermoplastic resin as set forth in claim 6, wherein said resin flow disturbing section is a combination of said mechanism on the screw with a suitable recess construction formed on the cylinder inner wall.
Claim 10
Dependent Claim
40 words
An apparatus for extruding thermoplastic resin as set forth in claim 6, wherein the ratio between the mean space sectional areas across the screw and the cylinder of said resin flow disturbing section and said resin feeding section is 1:2-1:10.
Claim 11
Dependent Claim
36 words
An apparatus for extruding thermoplastic resin as set forth in claim 6, wherein said resin flow disturbing section comprises equipment including a ring valve mechanism and an axially movable screw, so that fluidic resistance is regulatable.
Claim 12
Dependent Claim
29 words
An apparatus for extruding thermoplastic resin as set forth in claim 6, wherein the length of said resin flow disturbing section is 0.1-3 times the diameter of said cylinder.
Claim 13
Dependent Claim
40 words
An apparatus for extruding thermoplastic resin as set forth in claim 6, wherein said resin transfer section for relaxing the stress comprises at least one of a helical screw, a rod without helixes, a non-screw section only with a cylinder.
Claim 14
Dependent Claim
28 words
An apparatus for extruding thermoplastic resin as set forth in claim 6, wherein the length of said resin transfer section is 4-15 times the diameter of said cylinder.
Claim 15
Dependent Claim
42 words
An apparatus for extruding thermoplastic resin as set forth in claim 6, wherein said resin transfer section for relaxing the stress is provided between a mechanism comprising a screw and a cylinder and said die with a pipe and/or a gear pump.
Claim 16
Dependent Claim
33 words
An apparatus for extruding thermoplastic resin as set forth in claim 6, wherein the ratio (L/D) between the total length (L) and the diameter (D) of said screw of the extruder is 15-35.
Claim 17
Dependent Claim
58 words
An apparatus for extruding thermoplastic resin as set forth in claim 6, wherein said screw of the extruder comprises: a resin feeding-melting section including a straight screw; a resin flow disturbing section including at least one of a torpedo mechanism and a ring valve mechanism; and a transfer section including a straight screw, for relaxing the resin stress.
Claim 18
Dependent Claim
50 words
An apparatus for extruding thermoplastic resin as set forth in claim 6, wherein the ratio (H/h) between the depth of screw channel (H) of said straight screw and a space (h) formed between at least one of a torpedo and a ring valve mechanism portion and said cylinder is 2-10.
Claim 19
Dependent Claim
34 words
An apparatus for extruding thermoplastic resin as set forth in claim 6, wherein said cylinder of the resin feeding section of the extruder is formed with a grooved liner in the axial direction thereof.
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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) | 1990-05-18 | 1990-11-17 | 1991-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-18 | 1994-11-17 | 1995-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-18 | 1998-11-17 | 1999-05-19 | $7700.00 | Window Closed / Lapsed |