Method of aerodynamic texturing, texturing nozzle, nozzle head and use thereof

摘要

PCT No. PCT/CH97/00045 Sec. 371 Date Feb. 25, 1998 Sec. 102(e) Date Feb. 25, 1998 PCT Filed Feb. 12, 1997 PCT Pub. No. WO97/30200 PCT Pub. Date Aug. 21, 1997A method of air jet texturing is described wherein the intensity of texturing is proposed to be increased in that an air flow exceeding Mach 2 is obtained by the design of the nozzle duct. The total opening angle of the nozzle duct (11) directly in front of the texturing zone is designed to be greater than the ideal Laval angle with an effective length which is preferably a multiple of the smallest diameter of the nozzle. This predominantly improves the quality of texturing, quite particularly at higher production rates. These can be increased into the range of 600 to 1000 m/min and higher. It has surprisingly been found that the novel nozzle core (10) can be designed so that it has all advantages of the novel invention and can be used as a substitute for prior art nozzle cores. The same applies to the complete texturing head as the novel invention can be used within the same geometric external dimensions, the same air pressure and the same quantity of air.