초록 ▼

The closure unit can be manufactured in a single deep-drawing operation. During the course of a predetermined stroke of the single deep-drawing operation, such as the downward stroke up to a lower dead-center position, a blank is punched out, a ring or marginal rim and a collar are formed, a central

The closure unit can be manufactured in a single deep-drawing operation. During the course of a predetermined stroke of the single deep-drawing operation, such as the downward stroke up to a lower dead-center position, a blank is punched out, a ring or marginal rim and a collar are formed, a central opening is punched out and a section extending peripherally to the cut edge is downwardly extended. During the upward stroke predetermined sections of the extended collar are rolled and subsequently squeezed together.

대표청구항 ▼

A closure unit formed of sheet metal for sterilizable containers, comprising: a holding ring having a ring area; said ring area having a sealing surface; said holding ring being flangeable to an associated sterilizable container; said ring area defining a closure opening having a cut edge; said cut

A closure unit formed of sheet metal for sterilizable containers, comprising: a holding ring having a ring area; said ring area having a sealing surface; said holding ring being flangeable to an associated sterilizable container; said ring area defining a closure opening having a cut edge; said cut edge of said closure opening being bent over into said ring area; a membrane having a tear-back tab; said membrane covering said closure opening and being sealed onto said sealing surface of said ring area; said ring area comprising three substantially parallel, superjacent and folded material sections; said three substantially parallel, superjacent and folded material sections defining a top material section forming said sealing surface of said ring area, an intermediate material section and a bottom material section; and said cut edge being located at said intermediate material section between said top material section and said bottom material section.