| 摘要 |
Fibers displaced by needle penetration are pressed deeply between belt bristles. At this depth, sufficient static friction exists between bristles and fleece, that needle retraction does not raise the fleece fabric bodily. An Independent claim is included for the corresponding fabric structuring equipment. Vertical stroke and needle (21) adjustment at the needling beds (20a, 20b) are matched to achieve the required depth of insertion into fleece (5) and bristles of the brush pile belt (7). Preferred features: The fibrous fleece band is kept down in a zone around the first needle insertion, by a hold-down foot (22). The fleece is needled in successive zones, being pressed against the brush pile between them. During insertion, the needles are moved along with the fleece, by their own drives. The fleece is needled with differing densities in successive needling zones. Initially the needling density is low, with progression to higher needling density. First and second needling beds (20a, 20b) are adjusted for progressive depths of needling. The needle beds are coupled with a drive (16-19) promoting both vertical and horizontal motions to match belt movement. |
