| 摘要 |
The apparatus applies a transverse zipper strip to a film ( 10 ) moving continuously in a direction ( 12 ). A continuous belt ( 18 ) is driven by sprocket wheels ( 16 a , 16 b) and carries upper seal bars ( 22 a , 22 b , 22 c) which receive pre-cut lengths of zipper at station ( 3 ). The pre-cut lengths are attached to the film ( 10 ) by a lower seal bar ( 24 ) which moves towards the film ( 12 ) at position A when an upper seal bar carrying a zipper strip is located directly above the film. Sealing takes place as the upper and lower seal bars move at the same speed as the film ( 12 ) from position A to position B where the zipper is released from the upper seal bar ( 22 c). The process then repeats for the next zipper strip length. |
