| 摘要 |
In applying an unthreaded metal closure to the threaded neck of a bottle by the use of profiled thread rollers to shape the skirt of the closure shell into conformity with the bottle thread while the shell is pressed down on the mouth of the bottle, the part of the skirt in which the thread is formed is engaged during the thread-rolling operation by at least one plain roll angularly displaced with respect to the thread rollers. |
