US3908522A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of bags and sacks
Assignee: Hoechst AG
•
Filing: 1973-06-27
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Granted: 1975-09-30
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Expires: 1993-06-27
Abstract
Abstract This invention relates to a process for the production of containers from thin-walled, stretched, seamless tubes of thermoplastic material which comprises introducing a collapsed tube into an open clamp in a manner such that the edge of the tube projects beyond the clamp, closing the clamp, and fusing said projecting edge into a seam adjacent the clamp, the extent of the projecting portion of the tube being sufficient to produce a seam of a thickness of 2 to 10 times the total thickness of the superposed layers of film, and the fusing operation being effected at a temperature such that no degradation of the thermoplastic material results. The invention also includes an apparatus for performing the process.
Inventors
- 👤 Hugo Bender
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:38
CPC Classifications
B; B31; B31B; B31B70/00; B29; B29C; B29C65/00; B29C65/02; B29C65/10; B29C65/106; B29C66/00; B29C66/01; B29C66/02; B29C66/022; B29C66/0222; B29C66/024; B29C66/0242; B29C66/05; B29C66/10; B29C66/11; B29C66/112; B29C66/1122; B29C66/13; B29C66/137; B29C66/40; B29C66/41; B29C66/43; B29C66/431; B29C66/4312; B29C66/70; B29C66/73; B29C66/737; B29C66/7371; B29C66/73711; B29C66/73713; B29C66/73715; B29C66/739; B29C66/7392; B29C66/73921; B29C66/80; B29C66/83; B29C66/832; B29C66/8322; B29C65/14; B29C65/1403; B29C65/1412; B29C65/16; B29C66/71; B29C66/82; B29C66/824; B29C66/8242; B29L; B29L2031/00; B29L2031/712; B29L2031/7128; B31B2155/00; B31B2155/003; B31B2160/00; B31B2160/10
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
111 words
A process for the production of containers from thin-walled, stretched, seamless tubes of thermoplastic material which comprises introducing a collapsed tube into an open clamp in a manner such that the edge of the tube projects beyond the clamp, closing the clamp, and fusing said projecting edge into a seam adjacent the clamp, the extent of the projecting portion of the tube being sufficient to produce a seam of a thickness of 2 to 10 times the total thickness of the superposed layers of film, and the fusing operation being effected at a temperature such that no degradation of the thermoplastic material results, and stretching the seam of the completed container.
Claim 2
Dependent Claim
111 words
A process for the production of containers from thin-walled, stretched, seamless tubes of thermoplastic material which comprises introducing a collapsed tube into an open clamp in a manner such that the edge of the tube projects beyond the clamp, closing the clamp, and fusing said projecting edge into a seam adjacent the clamp, the extent of the projecting portion of the tube being sufficient to produce a seam of a thickness of 2 to 10 times the total thickness of the superposed layers of film, and the fusing operation being effected at a temperature such that no degradation of the thermoplastic material results, and stretching the seam of the completed container.
Claim 3
Dependent Claim
12 words
A process according to claim 1 in which the stretching is multiaxial.
Claim 4
Dependent Claim
16 words
A process according to claim 1 in which the stretching is effected at an elevated temperature.
Claim 5
Independent Claim
87 words
An apparatus for the production of containers from thin-walled, stretched, seamless tubes of thermoplastic material comprising transport means for introducing a predetermined length of seamless tubing into a clamp means, said clamp means comprising an upper and lower portion, means for opening and closing said clamp means, cutting means for forming a projection in front of the edge of the clamp means, means for fusing said projection, stretching station means for stretching said fused material, and means for removing the welded container from the open clamp means.
Claim 6
Independent Claim
87 words
An apparatus for the production of containers from thin-walled, stretched, seamless tubes of thermoplastic material comprising transport means for introducing a predetermined length of seamless tubing into a clamp means, said clamp means comprising an upper and lower portion, means for opening and closing said clamp means, cutting means for forming a projection in front of the edge of the clamp means, means for fusing said projection, stretching station means for stretching said fused material, and means for removing the welded container from the open clamp means.
Claim 7
Dependent Claim
21 words
An apparatus according to claim 4 in which the stretching station includes a pair of rollers for calendering the welded seam.
Claim 8
Dependent Claim
29 words
An apparatus according to claim 4 including a heat source in the stretching station which heats the fused seam to a stretching temperature appropriate for the thermoplastic material employed.
Claim 9
Dependent Claim
17 words
An apparatus according to claim 6 in which the heat source includes means for regulating the temperature.
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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) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |