Patent EA-002042-B1 (EA)
Title: Fiber distributor
IPC: D04H1/72
Filed: 1998-12-23
Abstract: 1. A forming box for use in dry forming of a fibrous tissue and comprising an inlet for introduction of an up-splitted fibre material, which is chosen among synthetic fibres and natural fibres, and which are mixed up in an air stream, the forming box being positioned above a forming wire opposite to a vacuum box, and the forming box containing several rotating rollers, which are provided with radially extending spikes, characterized in that the forming box is gridless and has an open bottom for delivery of the fibre material onto the forming wire, the spikes being adapted to partly retain the fibres against the influence from the suction of the vacuum box. 2. A forming box according to claim 1, characterized in that the spikes substantially cover an entire sectional area of the forming box as seen in a substantially horizontal plane. 3. A forming box according to the claim 1, characterized in that the rollers are oriented in a substantially horizontally plane. 4. A forming box according to the claims 1 or 2, characterized in that the rollers are oriented in a substantially vertically plane. 5. A forming box according to any of the claims 1-3, characterized in that the rollers are mounted displaceable in a substantially horizontal plane and can be placed with a mutual distance, which approximately corresponds up to, the diameter of a circle, defining the outer ends of the spikes. 6. A forming box according to any of the claims 1-3 or 5, characterized in that a layer of rollers is placed in a row with their longitudinal axes oriented in parallel and perpendicularly to the movement direction of the forming wire. 7. A forming box according to any of the claims 1-3 or 5, characterized in that more layers of rollers are placed above each other, where the rollers in each layer are established with longitudinal axes in the same or different orientation in relation to the rollers in one of the other layers. 8. A forming box according to any of the claims 1-3, characterized in that the rollers provided with spikes substantially form at least one hollow cylinder, the rollers being established in a cylinder expanse, and the inlet being established for introduction of fibres into the hollow cylinder. 9. A forming box according to claim 8, characterized in that within the cylinder at least one further roller is established, which is provided with spikes, and which is arranged adjacent to the cylinder, so that the diameter of the circle which is defined by the spikes on the rollers, substantially touch each other. 10. A forming box according to claim 8 or 9, characterized in that the cylinders are in pairs with the inlets established from opposite sides, and that the ends of the cylinders are connected to linking channels, which allow fibres to pass from the inner of a cylinder to the outer of an adjacent cylinder. 11. A forming box according to any of the claims 8-10, characterized in that the inlets of each cylinder are connected to separate supply sources for fibres for forming of a tissue with varying fibre properties over the thickness. 12. A forming box according to any of the claims 1, 2 or 4, characterized in that the spikes are established with substantially plate-formed wings in a plane perpendicular to the longitudinal axis of the rollers. 13. A forming box according to claim 12, characterized in that the plate-formed wings are angled in relation to a plane perpendicular to the longitudinal axis of the roller. 14. A forming box according to claim 12 or 13, characterized in that the wings are provided with holes in order to facilitate passage through the forming box. 15. A forming box according to any of the preceding claims, characterized in that the rollers are adapted for being rotated around their longitudinal axes with varying rates and in the varying direction. 16. A forming box according to any of the preceding claims, characterized in that the spikes, in the longitudinal direction of the roller, are spaced, which allow the passage in-between for corresponding spikes on an adjacent roller, and that the spikes are placed in a replacement rail being mounted in an axial direction in the roller. 17. A forming box according to any of the preceding claims, characterized in that the spikes on each roller are placed in a plane perpendicular to the longitudinal axis of the roller, and that a number of spike sets is established above the length of the roller, and that each set contains 2-12 spikes, preferably 4-8 spikes, and being evenly distributed along the circumference of the roller. 18. A forming box according to claim 1, characterized in that at least an end wall of the forming box, which extends across the forming wire, and which is positioned at an outlet side of the forming box, is adapted for being displaceable in the height direction perpendicular to the underlying forming wire for manufacturing of products with different heights. 19. A forming box according to any of the claims 1-11 and 15-18, characterized in that the axial distance between the spikes is between 5 and 20 mm and that the thickness of the spikes is between 0.5 and 10 mm and that the length of the spikes is between 5 and 200 mm, and that the rollers are adapted for variable positioning of the number of revolutions in an area between 200 and 5000 r.p.m. 20. A forming box according to claim 1, characterized in that the inlet can be placed in the side walls, the end walls, or the top of the forming box.