| 摘要 |
The inventions relate to production of piercing and cutting tapes, which are used as safety barriers. A method of making a piercing-cutting tape consists in that from a continuous metal strip several piercing-cutting tapes are simultaneously made by punching an even number of oval holes on width of a workpiece and cutting in a staggered-order of crosspieces between the adjacent edges along the length of oval holes for formation of opposite pairs of elements. Each element consists of a base and opposing teeth located on the outside of element, and the tops of each of teeth are the angles formed between the outer side and sides of element. According to the first invention, punching the oval-shaped openings and cutting the crosspieces between them is carried out in three stages, at the first of which punching the oval pair holes is carried out on the width of workpiece in two rows, at the second stage, after moving the workpiece for one step - cutting the part of pair crosspieces is carried out between the oval holes adjacent along the tape, at the third stage, after moving the workpiece for another half step - cutting the remaining pair crosspieces is carried out on the other line of location (staggered-order) in the workpiece. The stamp consists of a die and a punch, which comprises several pairs of punch elements, each of which consists of two successive finger punch elements of oval cross section, and punch elements of rectangular cross-section. According to the second invention, in the stamp the pairs of finger punching elements of oval cross-section are first located in two rows, behind which at a distance of one step of the workpiece movement the first row of part of punching elements of rectangular cross-section is located, behind which at a distance of a half step of the workpiece movement the second row of punching elements of rectangular cross-section is located in a staggered-order relative to the first row. Technical advantages: absence of deformation of piercing-cutting tapes under the stamp, there is no need for additional intermediate operation of alignment of the piercing-cutting tapes, continuous technology of manufacturing piercing and cutting tapes, simplification of the stamp design. |
