US3846531A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Finishing hollow blow molded articles
Assignee: Monsanto Co
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Filing: 1972-10-19
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Granted: 1974-11-05
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Expires: 1992-10-19
Abstract
Abstract A method for finishing a blow molded plastic article having flash attached to a neck portion thereof which includes gripping and relatively moving the flash and the article away from each other to sever the flash at a portion immediately adjacent the end of the neck which is at an elevated temperature with respect to the neck portion, and thereafter advancing a forming mandrel into the neck to roll an irregular edge left in the area of flash severance forwardly toward the body of the article and outwardly against the wall of the neck to form a smooth finish. The apparatus includes an inwardly directed step in the blow mold at the extremity of the neck defining portion of the mold whereat a thickened and therefore elevated temperature portion of the plastic is formed on expanding the parison, this thickened section being the area where severing occurs during finishing.
Inventors
- 👤 J Reilly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:44
CPC Classifications
B; B29; B29C; B29C49/00; B29C49/42; B29C49/76; B29C49/761; B29C49/48; B29C49/50; B29C49/72; B29C49/74
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
189 words
A method of finishing a blown hollow thermoplastic article having waste flash attached to a neck portion which comprises: a. establishing a difference in temperature in the forming cavity between the neck portion and a flash portion adjacent said neck portion which is thicker than that of said neck portion, the temperature of said neck portion being sufficiently low as to resist substantial deformation on application of a force thereto and the temperature of said thickened portion being 25* to 100*F. in excess of that of the neck portion but below that at which the plastic is incapable of sustaining its form; b. gripping the waste flash; c. relatively moving the gripped waste flash and the article away from each other to sever the flash from the neck in the area of the thickened portion leaving an irregular lip extending around the opening at the outer end of the neck; and then d. advancing a forming mandrel into said opening to roll said lip forwardly toward the body of the article and outwardly toward the wall of the blown neck to form a smooth neck finish on the article.
Claim 2
Independent Claim
189 words
A method of finishing a blown hollow thermoplastic article having waste flash attached to a neck portion which comprises: a. establishing a difference in temperature in the forming cavity between the neck portion and a flash portion adjacent said neck portion which is thicker than that of said neck portion, the temperature of said neck portion being sufficiently low as to resist substantial deformation on application of a force thereto and the temperature of said thickened portion being 25* to 100*F. in excess of that of the neck portion but below that at which the plastic is incapable of sustaining its form; b. gripping the waste flash; c. relatively moving the gripped waste flash and the article away from each other to sever the flash from the neck in the area of the thickened portion leaving an irregular lip extending around the opening at the outer end of the neck; and then d. advancing a forming mandrel into said opening to roll said lip forwardly toward the body of the article and outwardly toward the wall of the blown neck to form a smooth neck finish on the article.
Claim 3
Dependent Claim
11 words
The process of claim 1 wherein said article is a bottle.
Claim 4
Dependent Claim
24 words
The process of claim 2 which includes the step of removing the bottle from a mold prior to severing the flash from the neck.
Claim 5
Dependent Claim
12 words
The process of claim 1 wherein said article is a cylindrical preform.
Claim 6
Dependent Claim
27 words
The process of claim 1 wherein the flash is severed from the neck after the article is formed and while it is still in a forming mold.
Claim 7
Dependent Claim
26 words
The process of claim 1 wherein said article is fixed in position and severing is accomplished by pulling the flash away from the fixedly positioned article.
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) | 1977-11-04 | 1978-05-06 | 1978-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-04 | 1982-05-06 | 1982-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-04 | 1986-05-06 | 1986-11-05 | $7700.00 | Window Closed / Lapsed |