Method of forming wide-mouth, heat-set, pinch-grip containers
US6277321A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 9, 1998 |
| Grant date | Aug 21, 2001 |
| Priority date | — |
| Expiry date | Apr 9, 2018 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/716
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A wide-mouth, hot-fill plastic container having pinch-grips and a high push-up base and method for forming the same. According to the method, a preform is positioned in a mold cavity defined in part by surfaces which deviate substantially inward to form pinch-grips in the resulting container. Initially, a mold base is located so that it defines an initial mold cavity whose length is greater than the final length of the container. The preform is axially stretched in the cavity to a length greater than the containers final length. After stretching the preform, the preform is generally expanded radially outward under low pressure. The mold bottom is then moved to a position where the length of the cavity is about the same as the final length of the container. The preform is further expanded under high pressure such that it contacts the molding halves thereby forming the finished container. As a result of the above method, the base and contact ring of the container is fully circumferentially formed below the pinch-grips. The container is also heat treated to allow for filling with a hot product.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.