METHOD AND APPARATUS FOR DEFINING THE TEARING STRENGTH OF PAPER MATERIAL OR THE LIKE

摘要

The invention relates to a method for determining the internal bond strength of paper material or the like, in which two strips of one-sided tape (lla, llb) can continuously be taped to both sides of a sample (10), after which the tape and the sample are guided in between two separating cylinders (3a, 3b), set one against the other, in which the tape strips are separated from one another using re-directing cylinders (4a, 4b), which function as pulling elements, located some distance away from the separating cylinders, while at the same time, the force needed to separate the tape is measured and used to calculate the sample's internal bond strength. The invention also relates to an apparatus for applying a method, which is in accordance with Claim 1, which comprises a frame (12), to which is mounted at least two separating cylinders (3a, 3b), set one against the other, and re-directing cylinders (4a, 4b), placed some distance away from the separating cylinders, for guiding the tape strips (11 a, 11 b), which have been separated from the sample (10), apart from one another and for measuring the strain required in separating them. A characteristic of a method formed in accordance with the invention is that the tape strips (11 a, 11b) are guided to the re-directing cylinders (4a, 4b), such that the non­adhesive surfaces of the tape strips serve as the contact surface between the tape strips and the re-directing cylinders, and such that, after separated, the tape strips (lla, llb) and the sample (10) are guided in between cylinders (3a, 3b, 3c, 3d), which are set one against the other, and in between which the tape strips and the sample become taped together again. A characteristic of an apparatus constructed in accordance with the invention is that the re-directing cylinders (4a, 4b) are set at an angle in respect to the separating cylinders (3a, 3b), to move the tape strips primarily in a crosswise direction in relation to the separating cylinders (3a, 3b), in order to return them once again against one another.