EP 0020926 A1 19810107 - Method for necking thin wall metallic containers and drawn container produced by this method.
Title (en)
Method for necking thin wall metallic containers and drawn container produced by this method.
Title (de)
Verfahren zum Einhalsen dünnwandiger Metalldosen und nach diesem Verfahren hergestellte Dose.
Title (fr)
Procédé pour rétreindre des boîtes métalliques à paroi mince et boîte fabriquée d'après le procédé.
Publication
Application
Priority
- US 5157379 A 19790625
- US 12041980 A 19800212
Abstract (en)
The present invention relates to methods for reducing the open end of drawn and ironed containers such as beverage cans (20). It is desirable to provide a maximum reduction in diameter of the open end (36) in order to reduce the quantity of material in the lid (24); but previous forming methods have resulted in localized buckling in the reduced diameter portion (32) and/or crumpling of the transition portion. The present invention has solved the localized buckling and crumpling problems by a step wherein both the reduced diameter portion (32) and the transition portion are reformed within controlled limits to provide a new reduced diameter portion and a new curvilinear transition portion. Principal uses include the manufacture of beverage cans.
IPC 1-7
IPC 8 full level
B21D 51/26 (2006.01)
CPC (source: EP)
B21D 51/2615 (2013.01); B21D 51/2638 (2013.01); B65D 7/48 (2013.01)
Citation (search report)
- GB 1356821 A 19740619 - CROWN CORK & SEAL CO
- US 3995572 A 19761207 - SAUNDERS WILLIAM T
- US 3786957 A 19740122 - HILGENBRINK J
- US 3964413 A 19760622 - SAUNDERS WILLIAM T
- DE 2218396 A1 19731025 - KRUPP GMBH
- US 3898828 A 19750812 - CASSAI EUGENE, et al
Designated contracting state (EPC)
AT BE CH DE FR GB IT LI LU NL SE
DOCDB simple family (publication)
EP 0020926 A1 19810107; ES 492329 A0 19810416; ES 8104020 A1 19810416
DOCDB simple family (application)
EP 80102224 A 19800425; ES 492329 A 19800611