US4053274A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tube wall forming apparatus
Assignee: Individual
•
Filing: 1975-01-28
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Granted: 1977-10-11
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Expires: 1995-01-28
Abstract
Abstract An apparatus and method are provided for forming tubing of plastic which is forced through a die over a mandrel wherein the inside surface of the tubing is relatively smooth in configuration and the exterior surface thereof is formed with one or more helical ribs or teeth protruding outwardly therefrom which serve to enhance the rigidity of the tube wall and, when the plastic itself is relatively rigid, to render the tube wall more flexible so that it may be deformed or bent without collapsing. In one form, the extrusion die through which the extrusion material is forced to form the tube, is configured to provide the helical formations in the outer stratum of the tube wall and is power rotated as the extrudate is forced through the die to form the helical formation therein. In another form, a portion of the extrusion die is power rotated to form the helical formation. In a third form, control of the rotation of the die or a device located at the throat or exit of the die is affected to perform either or both of the functions of variably changing the shape of the helical formation and, providing portions of the tubing which are free of the helical formation to permit fittings to be attached thereto.
Inventors
- 👤 Jerome H. Lemelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:11
CPC Classifications
B; B29; B29C; B29C59/00; B29C59/02; B29C59/021; B29C48/00; B29C48/03; B29C48/09; B29C48/25; B29C48/30; B29C48/32; B29C48/33; B29C48/001; B29C48/0022; B29C48/13; B29L; B29L2023/00; B29L2023/003
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
255 words
An apparatus for continuously extruding tubing having a smooth interior wall surface which has a substantially constant internal diameter and having an exterior wall which varies in configuration along the length thereof wherein said configuration is in the form of corrugations having a depth equal to at least one-half of the wall thickness of the extruded tube to provide a flexible tube having a resistance free flow path comprising: an extruder including an extrusion die having a die opening, a mandrel supported within said die and extending beyond said die opening to define with said die opening an annular passageway, means connected to said die to define a chamber adapted to be filled with an extrudate, means associated with said chamber for forcing the extrudate about said mandrel and through said annular passageway, said mandrel having a smooth outer surface to form the tubular extrusion having a smooth regularly shaped internal surface having a substantially constant diameter, corrugating means operatively associated with said die and having a corrugating formation for engaging the exterior surface of the tubular extrusion formed in said die, said corrugating formation having a depth equal to at least one-half the thickness of tubular extrusion formed in said die, drive means connected to said corrugating means for effecting the rotation thereof as said tubular extrusion is being formed in said die to form a series of spiral protrusions in the outer stratum of the tubular extrusion only, wherein said corrugating means comprises a component part of said die defining said die opening.
Claim 2
Independent Claim
255 words
An apparatus for continuously extruding tubing having a smooth interior wall surface which has a substantially constant internal diameter and having an exterior wall which varies in configuration along the length thereof wherein said configuration is in the form of corrugations having a depth equal to at least one-half of the wall thickness of the extruded tube to provide a flexible tube having a resistance free flow path comprising: an extruder including an extrusion die having a die opening, a mandrel supported within said die and extending beyond said die opening to define with said die opening an annular passageway, means connected to said die to define a chamber adapted to be filled with an extrudate, means associated with said chamber for forcing the extrudate about said mandrel and through said annular passageway, said mandrel having a smooth outer surface to form the tubular extrusion having a smooth regularly shaped internal surface having a substantially constant diameter, corrugating means operatively associated with said die and having a corrugating formation for engaging the exterior surface of the tubular extrusion formed in said die, said corrugating formation having a depth equal to at least one-half the thickness of tubular extrusion formed in said die, drive means connected to said corrugating means for effecting the rotation thereof as said tubular extrusion is being formed in said die to form a series of spiral protrusions in the outer stratum of the tubular extrusion only, wherein said corrugating means comprises a component part of said die defining said die opening.
Claim 5
Dependent Claim
64 words
The invention as defined in claim 1 and including means operatively associated with said drive means for intermittently operating said drive means so as to effect intermittent operation of said corrugating means to provide a tubular extrusion having a helical rib-like formation extending along preselected portions of the outer stratum thereof and having other portions of said outer stratum void of said rib-like formations.
Claim 8
Dependent Claim
101 words
An apparatus in accordance with claim 1 wherein said corrugating means includes a forming tool disposed about said die opening and located to engage the outer stratum of the tubular extrusion expressed through said die opening wherein said forming tool includes a cylindrical die rotatably supported around and concentric with said extrusion die, said cylindrical die having a corrugated internal surface, and said drive means operatively associated with said die for rotating said cylindrical die around said tubular extrusion to cause the corrugated internal surface thereof to engage and form the outer stratum of said tubular extrusion with helically extending ribs.
Claim 11
Dependent Claim
110 words
An apparatus as defined in claim 1 wherein said corrugating means includes a forming tool disposed about said die opening and located to engage the outer stratum of the tubular extrusion expressed through said die opening, wherein said forming tool comprises a forming die with a circular corrugated opening therein, means operatively associated with said extrusion die for rotatably supporting said forming die exteriorly of said extrusion die in a position to receive the tubular extrusion, and said drive means rotating said forming die to form on the outer surface of said tubular extrusion a series of helical rib formations as said extrusion tube is expressed through said die opening.
Claim 12
Dependent Claim
20 words
An apparatus in accordance with claim 1, said mandrel being shaped to normally prevent rotation of the extrusion formed thereon.
Claim 13
Independent Claim
271 words
An apparatus for continuously extruding tubing having a smooth interior wall surface which has a substantially constant internal diameter and having an exterior wall which varies in configuration along the length thereof wherein said configuration is in the form of corrugations having a depth equal to at least one-half of the wall thickness of the extruded tube to provide a flexible tube having a resistance free flow path comprising: an extruder including an extrusion die having a die opening, a mandrel supported within said die and extending beyond said die opening to define with said die opening an annular passageway, means connected to said die to define a chamber adapted to be filled with an extrudate, means associated with said chamber for forcing the extrudate about said mandrel and through said annular passageway, said mandrel having a smooth outer surface to form the tubular extrusion having a smooth regularly shaped internal surface having a substantially constant diameter, corrugating means operatively associated with said die and having a corrugating formation for engaging the exterior surface of the tubular extrusion formed in said die, said corrugating formation having a depth equal to at least one-half the thickness of tubular extrusion formed in said die, drive means connected to said corrugating means for effecting the rotation thereof as said tubular extrusion is being formed in said die to form a series of spiral protrusions in the outer stratum of the tubular extrusion only, wherein said corrugating means includes a plurality of forming tools disposed about said die opening and located to engage the outer stratum of the tubular extrusion expressed through said die opening.
Claim 14
Independent Claim
271 words
An apparatus for continuously extruding tubing having a smooth interior wall surface which has a substantially constant internal diameter and having an exterior wall which varies in configuration along the length thereof wherein said configuration is in the form of corrugations having a depth equal to at least one-half of the wall thickness of the extruded tube to provide a flexible tube having a resistance free flow path comprising: an extruder including an extrusion die having a die opening, a mandrel supported within said die and extending beyond said die opening to define with said die opening an annular passageway, means connected to said die to define a chamber adapted to be filled with an extrudate, means associated with said chamber for forcing the extrudate about said mandrel and through said annular passageway, said mandrel having a smooth outer surface to form the tubular extrusion having a smooth regularly shaped internal surface having a substantially constant diameter, corrugating means operatively associated with said die and having a corrugating formation for engaging the exterior surface of the tubular extrusion formed in said die, said corrugating formation having a depth equal to at least one-half the thickness of tubular extrusion formed in said die, drive means connected to said corrugating means for effecting the rotation thereof as said tubular extrusion is being formed in said die to form a series of spiral protrusions in the outer stratum of the tubular extrusion only, wherein said corrugating means includes a plurality of forming tools disposed about said die opening and located to engage the outer stratum of the tubular extrusion expressed through said die opening.
Claim 17
Dependent Claim
62 words
The invention as defined in claim 6 wherein said forming tool includes a plurality of cylindrical members disposed about said die opening, each of said cylindrical members having external corrugation formations on the outer surface thereof, said surface being disposed in engagement with the outer stratum of the tubular extrusion to form complementary corrugations in the outer stratum of the tubular extrusion.
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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) | 1980-10-10 | 1981-04-11 | 1981-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-10 | 1985-04-11 | 1985-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-10 | 1989-04-11 | 1989-10-11 | $7700.00 | Window Closed / Lapsed |