Disc removal end wall structure with safety features
US4848623A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1977 |
| Grant date | Jul 18, 1989 |
| Priority date | — |
| Expiry date | Jun 28, 1997 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65D2517/0079
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A full-open, disc-removal, end wall structure (25) with improved easy-open lever action and edge-protection features is disclosed along with methods of fabricating and opening. A back-scoreline (38, 52) is ruptured, by Class 2 lever action, upon lifting of a rigid (non-lanced) tap opener (28, 51, 63) as the working end (32) of the tab opener ruptures a portion of peripheral scoreline (33); continued movement of the tab opener in the direction (46) into contact with chime seam (47) provides for continued lever-action rupture of the peripheral scoreline by Class 1 lever action about the chime seam as a fulcrum. Multi-folds of sheet metal provide rounded edge metal (73, 78) shilding for residual scoreline metal; pre-folding of the metal is carried out while leaving access for scoring tooling (86, 88) to enable scoring on a single thickness of sheet metal; and so as to avoid premature damage to the residual scoreline metal upon final orientation. Rivet button (83) and riveting of the tab opener to the removable disc (30) are carried out in the metal folding sequence.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.