Apparatus for molding a plastic article
US4266927A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 19, 1979 |
| Grant date | May 12, 1981 |
| Priority date | — |
| Expiry date | Jul 19, 1999 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2043/527
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Apparatus and method are disclosed for closing and sealing a molded plastic article formed by expanding a heated plastic parison within a chamber or cavity defined by a plurality of mold sections. The article is closed and sealed by at least one movable sealing member which has a protruding pinch surface to weaken or sever the parison and recess surface portions selectively above or below the protruding pinch surface which provide plastic-receiving reservoirs that aid in the formation of an unobtrusive seal adjacent the surface of the article. The sealing member may also include parison engaging seat or heel portions which further aid in the sealing operation. The temperature of the mold sections adjacent the sealing operation is controlled to selectively retard the cooling of the parison, which is in direct contact with the cavity surface, to maintain the parison at a sufficiently elevated temperature to permit closing and sealing by the sealing member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.