摘要 |
In a winder (10) for winding webs from a bag-making machine into rolls, a winding turret (12) mounts four winding spindles (22,24,26,28), each having a web-winding portion and a pulley-mounting portion, which mounts a conjointly rotatable pulley and an independently rotatable pulley. A first timing belt (120) and a second timing (130) belt are arranged to be independently driven. The winding turret (12) is indexable so that, in any indexed position, a first timing belt (120) interengages the conjointly rotatable pulley mounted on the given winding spindle and interengages the independently rotatable pulley mounted on the next winding spindle and a second timing belt (130) interengages the independently rotatable pulley mounted on the given winding spindle and interengages the conjointly rotatable pulley mounted on the next winding spindle. The rotational speeds of a motor driving a given winding spindle, whichever is being used to complete winding of a roll, and the rotational speed of a motor driving a web conveyor are measured. The motor driving the same winding spindle is adjusted so as to maintain a generally constant winding tension on a web being wound. A pair of infeeding rollers (30,32) and a pair of separating rollers (40,42) are operated so as to apply a generally constant winding tension to a web (W), except during intervals during which the surface speed of the separating rollers (40,42) exceeds the surface speed of the infeeding rollers (30,32) so as to separate the web at cross perforations. |