GB1104389A - Apparatus for uniform web feed - Google Patents

Abstract

1,104,389. Automatic tension control. CONSOLIDATED CIGAR CORPORATION. July 19, 1966 [April 12, 1966], No.32425/66. Heading G3R. Uniform tension is maintained in a web by a tension detector engaging and disengaging a clutch coupling a high speed drive to the web so as to over-ride a low speed drive which is coupled through an over-running clutch. In Fig. 1, overlapping and laterally offset cigar binder and wrapper bands B of reconstituted tobacco are drawn from reels 17 and 18 and helically wound on a tobacco rod in a cigar making machine 11. The tension in each band is automatically controlled in a similar manner and, considering one band, reel 17 is braked by a roller 32 incorporating an adjustable frictional device resisting rotation. The band is withdrawn from reel 17 by a driven feedroller 49 geared to a pressure roller 57 which is eccentrically mounted and spring- loaded towards roller 49. Roller 49 is normally driven at a low speed from a shaft 82 through a first chain 78a and an over-running clutch, but, as machine 11 consumes the band, a lever 97, resting in a loop of the band, is raised until a switch S 2 is cam-operated to energize, through a relay system, an electromagnetic clutch incorporated in the drive to roller 49 so that the latter is driven faster through a second chain 79a. When lever 97 falls sufficiently, a second switch S 1 is cam-operated to restore the low speed drive. Thereafter the speed of roller 49 alternates between the two values to maintain loop length, and hence tension, between limits. Weighting of lever 97 and the position of the switch cams are adjustable to facilitate setting the tension limits.