GB1312581A - Yarn texturizing method and apparatus - Google Patents

Abstract

1312581 Compression crimping NORTH AMERICAN ROCKWELL CORP 23 April 1971 [18 May 1970] 10976/71 Heading D1F A method of processing a thermoplastic multifilament yarn comprises withdrawing the yarn from a supply and delivering the yarn to a confined texturizing zone where it is formed into a series of coils, the coils being compressed into overlapping relationship and held thus while the yarn is withdrawn from said zone and while the yarn is heated and then cooled. Apparatus for carrying out the method while the yarn is travelling in a forward direction includes a yarn delivery tube 64, a tube 75 of enlarged diameter relative to the tube 64 surrounding the latter at the delivery end thereof and extending forwardly therefrom and terminating in an open end, means surrounding said open end defining a yarn texturizing zone, said means including opposed endless belts 14, 15 providing a nip therebetween, means for advancing the belts 14, 15 in said forward direction, and means for supplying a whirling and forwardly moving air stream in the tube 75 to advance the yarn Y to the texturizing zone and to form spiral convolutions of the yarn at the nip of the belts 14, 15. The whirling air stream is provided by means comprising a first air chamber 62 to which pressurised air is supplied, the chamber 62 communicating with a second air chamber 63 by means of inclined passages provided in a dividing wall 61. The yarn delivery tube 64 extends through the chambers 62 and 63 and the dividing wall 61 and also through a bore 65 in the end wall 56 of the chamber 63. The tube 75 may be integral with the housing 55 of the chambers 62, 63 or attached thereto. The bore 65 is of the same diameter as the bore of the tube 75 so that an annular passage is formed round the delivery end of the tube 64. The projecting end of the tube 75 is surrounded by top and bottom walls 76, 77 and side walls 81 which extend to and conform to the surface of the belts 14, 15 as they pass round drive rolls 16, 18. The yarn Y is deposited in spiral coils at the nip of the belts and compressed into overlapping relationship by the forwardly advancing belts. The belts are arranged to advance at a greatly reduced rate relative to the yarn feed from the supply. Heaters are positioned adjacent the opposed runs of the belts 14, 15 whereby the yarn is set in the coiled condition. Cooling means arranged to pass pressurised air through the coils is also arranged adjacent the runs of the belts. The belts are preferably made of mesh material. The yarn is withdrawn from between the belts at a rate which causes the yarn to be extended to separate the coils. The yarn is then further extended to separate the filaments of the yarn and finally wound at a reduced rate relative to preceding feeding means whereby the yarn is partially relaxed and thus bulked.