Patent US4933869A successfully refreshed from Google Patents.
Patent US3887673A successfully refreshed from Google Patents.
US3887673A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method for manufacturing tubular film of thermoplastic resin
Assignee: Resonac Holdings Corp
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Filing: 1973-07-13
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Granted: 1975-06-03
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Expires: 1993-07-13
Abstract
Abstract The invention disclosed provides an apparatus and method for manufacturing tubular film by passing an extruded tubularly inflated thermoplastic resin film into a coaxial cooling hole of a water-cooling tank. The cooling hole is fitted with a pliable element over the cylindrical wall surfaces of a cooling zone, a sizing zone and a draining zone. In passing the cooling zone, the pliable element cools the film to a temperature just above the point of crystallization. In the sizing zone, the film is cooled to a temperature below the crystallization point and, at the same time, tubular form is conferred to the film by internal inflation pressure and by suction in the sizing zone. Water adhering to the surface of the film is removed at the draining zone.
Inventors
- 👤 Wasuke Sato
- 👤 Osamu Uemura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:51
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/88; B29C48/90; B29C48/901; B29C48/903; B29C48/03; B29C48/09; B29C48/10; B29C48/911; B29C48/9115; B29C48/912; B29C48/919; B29C48/001; B29C48/0018; B29C48/0019; B29C48/885; B29C48/904; B29C48/908
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
174 words
An apparatus for production of a tubular film of crystallized thermoplastic resin which comprises in combination, a thermoplastic resin extruding ring for extruding a tubular film of crystallizable thermoplastic film, an inflation means for inflating said tubular film, and a water-cooling tank, said water-cooling tank having an inner cylindrical wall defining a cooling zone, a sizing zone and a draining zone, a pliable cooling element having high water retention disposed over the inner cylindrical wall, a water supply chamber, one end of said pliable cooling element being immersed in water in said water supply chamber, suction orifices disposed through the cylindrical wall at the sizing zone and passing to a vacuum chamber, water draining orifices disposed through the cylindrical wall at the draining zone and passing to a water drain chamber, and means for passing tHe extruded film of thermoplastic film from the extruding ring into the water-cooling tank wherein the film is cooled to a temperature below the crystallization point at the sizing zone while under influence of internal pressure and external suction.
Claim 2
Independent Claim
174 words
An apparatus for production of a tubular film of crystallized thermoplastic resin which comprises in combination, a thermoplastic resin extruding ring for extruding a tubular film of crystallizable thermoplastic film, an inflation means for inflating said tubular film, and a water-cooling tank, said water-cooling tank having an inner cylindrical wall defining a cooling zone, a sizing zone and a draining zone, a pliable cooling element having high water retention disposed over the inner cylindrical wall, a water supply chamber, one end of said pliable cooling element being immersed in water in said water supply chamber, suction orifices disposed through the cylindrical wall at the sizing zone and passing to a vacuum chamber, water draining orifices disposed through the cylindrical wall at the draining zone and passing to a water drain chamber, and means for passing tHe extruded film of thermoplastic film from the extruding ring into the water-cooling tank wherein the film is cooled to a temperature below the crystallization point at the sizing zone while under influence of internal pressure and external suction.
Claim 3
Independent Claim
174 words
An apparatus for production of a tubular film of crystallized thermoplastic resin which comprises in combination, a thermoplastic resin extruding ring for extruding a tubular film of crystallizable thermoplastic film, an inflation means for inflating said tubular film, and a water-cooling tank, said water-cooling tank having an inner cylindrical wall defining a cooling zone, a sizing zone and a draining zone, a pliable cooling element having high water retention disposed over the inner cylindrical wall, a water supply chamber, one end of said pliable cooling element being immersed in water in said water supply chamber, suction orifices disposed through the cylindrical wall at the sizing zone and passing to a vacuum chamber, water draining orifices disposed through the cylindrical wall at the draining zone and passing to a water drain chamber, and means for passing tHe extruded film of thermoplastic film from the extruding ring into the water-cooling tank wherein the film is cooled to a temperature below the crystallization point at the sizing zone while under influence of internal pressure and external suction.
Claim 4
Independent Claim
174 words
An apparatus for production of a tubular film of crystallized thermoplastic resin which comprises in combination, a thermoplastic resin extruding ring for extruding a tubular film of crystallizable thermoplastic film, an inflation means for inflating said tubular film, and a water-cooling tank, said water-cooling tank having an inner cylindrical wall defining a cooling zone, a sizing zone and a draining zone, a pliable cooling element having high water retention disposed over the inner cylindrical wall, a water supply chamber, one end of said pliable cooling element being immersed in water in said water supply chamber, suction orifices disposed through the cylindrical wall at the sizing zone and passing to a vacuum chamber, water draining orifices disposed through the cylindrical wall at the draining zone and passing to a water drain chamber, and means for passing tHe extruded film of thermoplastic film from the extruding ring into the water-cooling tank wherein the film is cooled to a temperature below the crystallization point at the sizing zone while under influence of internal pressure and external suction.
Claim 5
Dependent Claim
18 words
The apparatus of claim 1 wherein the vacuum chamber and the water drain chamber define a common chamber.
Claim 6
Dependent Claim
23 words
The apparatus of claim 1 wherein the thickness of the extruded tubular film of crystallizable thermoplastic resin is in excess of 100 microns.
Claim 7
Dependent Claim
17 words
The apparatus of claim 1 wherein means are included for removing water from the water drain chamber.
Claim 8
Dependent Claim
28 words
The apparatus of claim 1 wherein the water supply chamber is disposed as an annular chamber about the inner cylindrical wall and includes a water make-up supply means.
Claim 9
Dependent Claim
19 words
The apparatus of claim 1 wherein air cooling means are provided between the extruding ring and the water-cooling tank.
Claim 10
Dependent Claim
20 words
The apparatus of claim 1 wherein the suction orifices are inclined downwardly in an inner direction from the suction chamber.
Claim 11
Dependent Claim
24 words
The apparatus of claim 1 wherein the water draining orifices are oblong and inclined upwardly in an inner direction from the water drain chamber.
Claim 12
Dependent Claim
21 words
The apparatus of claim 1 wherein a mandrel is disposed inside the tubularly inflated film along the cooling and sizing zones.
Claim 13
Dependent Claim
13 words
The apparatus of claim 9 wherein a coolant is circulated in the mandrel.
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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) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |