US4026984A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method forming an oriented article having a bead attached by a tapered stem
Assignee: Phillips Petroleum Co
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Filing: 1975-09-26
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Granted: 1977-05-31
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Expires: 1995-09-26
Abstract
Abstract The strength of the seal of an open end parison preform fabricated at orientation temperature is increased by forming a dependent bead within a closely adjacent longitudinal recess. In an alternate embodiment the appearance of seals is improved, and pin holes reduced by forming a dependent bead in a manner such that the longitudinal stem (web) connecting the bead flares outward adjacent a bottom wall of the article being molded.
Inventors
- 👤 Charles L. Seefluth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:56
CPC Classifications
B; B65; B65D; B65D1/00; B65D1/02; B65D1/0223; B65D1/0261; B65D1/0276; B29; B29C; B29C49/00; B29C49/08; B29C49/10; B29C49/14; B29C49/42; B29C49/48; B29C49/4802; B29C49/4817; B29C66/00; B29C66/01; B29C66/32; B29C66/326
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
191 words
A method for closing an open end thermoplastic parison which has been heated in the solid state to orientation temperature comprising: stretching said parison longitudinally; thereafter applying pressure along a narrow line to opposing side walls of said parison to sever said parison while simultaneously applying lateral pressure to said parison adjacent said severing line to mold said parison adjacent said severing line into a bead along the thus-formed sealing seam while applying pressure along a narrow line between said bead and a bottom wall of the resulting article to form a stem connecting said bead and said bottom wall, said stem being tapered with the wider base portion being adjacent said bottom wall and with sides of said stem sloping at an angle of 10 to 20 degrees so that said stem has a thickness adjacent said bottom wall 1.5 to 4 times a thickness thereof adjacent said bead; and maintaining pressure on said bead to hold said walls of said parison together and form a seal as blow fluid is introduced into the interior of said parison to cause same to conform to the shape of a molding zone.
Claim 2
Independent Claim
191 words
A method for closing an open end thermoplastic parison which has been heated in the solid state to orientation temperature comprising: stretching said parison longitudinally; thereafter applying pressure along a narrow line to opposing side walls of said parison to sever said parison while simultaneously applying lateral pressure to said parison adjacent said severing line to mold said parison adjacent said severing line into a bead along the thus-formed sealing seam while applying pressure along a narrow line between said bead and a bottom wall of the resulting article to form a stem connecting said bead and said bottom wall, said stem being tapered with the wider base portion being adjacent said bottom wall and with sides of said stem sloping at an angle of 10 to 20 degrees so that said stem has a thickness adjacent said bottom wall 1.5 to 4 times a thickness thereof adjacent said bead; and maintaining pressure on said bead to hold said walls of said parison together and form a seal as blow fluid is introduced into the interior of said parison to cause same to conform to the shape of a molding zone.
Claim 3
Dependent Claim
11 words
A method according to claim 1 wherein said polymer is polypropylene.
Claim 4
Dependent Claim
33 words
A method according to claim 1 wherein said pressure is applied by mold halves closing at a rate sufficient that the total closing time is within the range of 0.5 to 1 second.
Claim 5
Dependent Claim
54 words
A method according to claim 1 wherein said pressure applied along said narrow line between said bead and said bottom wall to produce said stem is applied so as to form said stem with a greater distance between said bead and said bottom wall in a center of said bead than at ends thereof.
Claim 6
Dependent Claim
17 words
A method according to claim 1 wherein said stem is formed within a closely adjacent longitudinal recess.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-30 | 1980-11-29 | 1981-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-30 | 1984-11-29 | 1985-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-30 | 1988-11-29 | 1989-05-31 | $7700.00 | Window Closed / Lapsed |