| 主权项 |
1. A separation unit for separating a web material along preformed lines of weakness, said separation unit having a width direction and comprising
at least a first roller a having a rotational axis extending in said width direction and a web width extending in said width direction, and at least a second roller having a rotational axis extending parallel with said rotational axis of said first roller and a web width extending in said width direction, said rotational axis of said second roller being positioned at a distance from said rotational axis of said first roller, said distance extending in a direction perpendicular to said width direction, wherein each of said first and said second rollers is provided with at least one protrusion element extending perpendicularly from said axes, wherein each of said protrusion elements has a maximum width in said width direction, a maximum radial extension from said rotational axes, an inner portion adjacent to said rotational axes and an outer portion from said rotational axes, wherein said outer portions of said protrusion elements on said first roller are arranged in a staggered relationship with said outer portions of said protrusion elements on said second roller, and wherein said outer portions of said protrusion elements on said first roller are partially overlapping with said outer portions of said protrusion elements on said second roller with a radial overlap length, thus forming an undulating passage for a web material between said rollers, wherein said distance between said rotational axes of said first and said second rollers is adjustable, enabling said radial overlap length in said undulating passage to be variable, and wherein a biasing means arranged with said rollers enables an automatic adjustment of said distance between said rotational axes of said first and said second rollers. |
