| 摘要 |
A film advance mechanism is used for advancing a tubular film along a film support with the film surrounding the support. The mechanism comprises two drive units each comprising a drive belt passing round two rollers mounted on a respective drive belt carrier and arranged so that a straight run of the belt can engage frictionally against the film to drive the film along the support. Each carrier is supported for movement towards and away from the film support and for angular movement with respect to the film support and is urged towards the film support such that it aligns itself with the film support due to engagement therewith.
|
