公开(公告)号：US3607550A

公开(公告)日：1971-09-21

申请号：US3607550D

申请日：1968-11-22

Applicant: DU PONT

Inventor： BALLANGER THOMAS CASS ,  SCHOONDERWOERD JAKE ,  OLDHAM JOHN H

IPC: B31B19/10 ,  B32B31/04

CPC classification number: B31B70/00 ,  B31B70/10 ,  B31B2160/10

Abstract: Disclosed herein is an apparatus for effecting longitudinally spaced apart transverse seals with a high degree of linear accuracy in a continuous web of plastic material having a plurality of layers. The apparatus comprises two sets of dual sealer drive rollers for advancing the web past the sealer, and a means for accurately controlling the operation of the sealer and drive rolls. This control means comprises a digital converter operatively in contact with the drive rollers, adapted to convert the angle through which the roller has rotated into a train of electrical pulses. A counter is operatively connected to the converter and is responsive to the train of pulses so that when a predetermined number of these pulses are recorded, an electrical signal is emitted that activates a brake to stop the drive rolls and concomitantly activates a sealer.