Patent ID: 6094961
Filing Date: 2000-08-01
Classification: B21D

Abstract:
A method of necking an open end of a container sidewall to form a neck profile comprising the steps of:a) positioning a container relative to a first necking die and a first punch sleeve;b) producing relative longitudinal movement of the container toward the first necking die to engage the open end of the container sidewall with the first necking die to deform the sidewall radially inward;c) maintaining a fixed position of the first necking die relative to the first punch sleeve during step b);d) pressurizing an interior of the container after the container engages the first necking die;e) producing relative longitudinal movement of the container away from the first necking die to disengage the container from the first necking die such that the container disengages from the first necking die before the container disengages from the punch sleeve; andf) passing compressed air through a substantially annular gap formed between the first punch sleeve and the first necking die while the container is disengaged from the first necking die and engaged with the punch sleeve.