Needle for needling flat textile fabrics
View Patent ↗A needle ( 1 ) according to the invention serves for the after-treatment, particularly after-needling of flat textile products, particularly for roughening of the product surface. The needle ( 1 ) is of fully symmetrical construction with respect to the central longitudinal axis ( 11 ); this applies particularly also to its barbs. The needle gauge is at least 46 and the barb depth is 0.02 mm at the most. The needle ensures a gentle, protective operation and the making of particularly fine textiles.
1. An after-treatment needle ( 1 ) for flat textile products, comprising
an axially elongated needle body ( 2 ) having at one end a clamping part ( 4 ) and at another end a working part ( 5 ) provided with n number of edges ( 6 , 7 , 8 , 10 ) extending in the axial direction of the needle body ( 2 ) and having a cross-sectional height of less than 0.35 mm, wherein n equals to or is greater than three, and
adjoining barbs ( 12 , 13 ) arranged at least at two edges ( 6 , 7 ); the adjoining barbs ( 12 , 13 ) have a depth which is less than 0.02 mm and are arranged pair-wise in the same axial position or on a helical line, whose pitch (G) is less than n times the length of the barb ( 12 ).
2. The after-treatment needle as defined in claim 1 , characterized in that the pitch (G) is less than twice the length of the barb ( 12 ).
3. The after-treatment needle as defined in claim 1 , characterized in that the working part ( 5 ) has a star-shaped cross section.
4. The after-treatment needle as defined in claim 1 , characterized in that the working part ( 5 ) has a three-edged or a four-edged cross section.
5. The after-treatment needle as defined in claim 1 , characterized in that the edges ( 6 , 7 , 8 , 10 ) are rounded.
6. The after-treatment needle as defined in claim 5 , characterized in that the radius of curvature (R) of the edges ( 6 , 7 , 8 ) is greater than one third of the radius (Ru) of a circumscribable circle about the cross section of the working part ( 5 ) of the needle ( 1 ).
7. The after-treatment needle as defined in claim 5 , characterized in that the radius of curvature (R) of the edges ( 6 , 7 , 8 ) is greater than one half of the radius (Ru) of a circumscribable circle about the cross section of the working part ( 5 ) of the needle ( 1 ).
8. The after-treatment needle as defined in claim 1 , characterized in that the needle body ( 2 ) has a substantially point-shaped tip ( 17 ) at the end remote from the clamping part ( 4 ).
9. The after-treatment needle as defined in claim 8 , characterized in that the tip ( 17 ) is edge-free.
10. The after-treatment needle as defined in claim 1 , characterized in that all the edges ( 6 , 7 , 8 ) are provided with barbs ( 12 , 13 , 14 ), and the barbs ( 12 , 13 , 14 ) are arranged in annular or crown-shaped regions.
11. The after-treatment needle as defined in claim 1 , characterized in that the barbs ( 12 , 13 , 14 ) are provided with a curvature about the central longitudinal axis ( 11 ) of the working part ( 5 ); the radius (Rs) of the curvature is less than the radius (Ru) of a circumscribable circle containing the cross section of the working part ( 5 ).
12. The after-treatment needle as defined in claim 1 , characterized in that the edges ( 6 , 7 , 8 , 10 ) are formed by planar, strip-shaped surface regions.