GB1361992A - Crimping apparatus and method for multifilament yarns - Google Patents

Abstract

1361992 Crimping yarns JOSEPH BANCROFT & SONS CO 11 June 1971 [11 June 1970] 27551/71 Headings D1F and DIW A stuffer crimper comprises a pair of feed rolls and a crimping and setting chamber including a saddle spanning the nip of the rolls and having planks extending over the end surfaces of the rolls, and a guide for traversing multifilament yarn along the nip, the minimum distance between the filaments at the ends of their traverse and the ends of the rolls being 0.05 inches. As shown, Fig. 3, a traverse roll 17 traverses yarn 16 along the nip between rollers 14 (not shown) and 15. A tube forming the crimping chamber connects with tubular saddle 30, Fig. 4, having flanges extending over the end faces of rolls 14, 15, and which may have an internal diameter of at least 0.27 inches. The angles 'A' between the roll radii to the nip and to the wiping edge of saddle 30 may be at least 29‹. The diameter of the rolls may lie in the range of 1.0 to 1.26 inches. A back weight may rest on the core of crimped yarn on the crimping chamber, and may be connected to a microswitch so that its positions controlls the rate of rotation of the feed rolls. The crimper, having a back weight and a crimping chamber whose length is at least twenty times its width, may be used to produce a crimped 40 to 200 denier nylon yarn being less than one turn of twist per inch and a bulk level of 18%-35%. The back weight may contribute 45% to 60% of the total bulk level. The same crimper may also be used to produce a crimped 40 to 200 denier polyester yarn having less than one turn of twist per inch and a bulk level of 10% to 28%. The back weight may contribute 33% to 50% of the total bulk level.