Patent GB-1051732-A (GB)
IPC: D01D10/04
Abstract: 1,051,732. Thread-treatment and advancing rolls. NELVALE Ltd. Aug. 7, 1964 [Aug. 27, 1963], No. 33831/63. Headings D1D and D1L. A thread treating machine of the skew roll type having a plurality of thread storing, thread advancing units, is characterized in that the lower of the conventional main thread storing, thread advancing rolls in a unit is replaced by a group of three main rolls whose axes lie at the corners of a triangle symmetrically disposed about the median plane of the unit and a plurality of treatment rolls, each of which is coextensive with a respective treatment zone, are mounted on an axis substantially parallel to those of the group of so as to engage the thread on at least one flight between successive rolls of the group and transfer treatment liquor thereto. In one embodiment. Figs. 1 and 2, three skew roll units 1, 2, 3 are shown side-by-side. The unit 1 comprises a relatively large diameter driven upper roll 10 and three small diameter driven rolls 12, 13, 14. The axes of the rolls 12, 13, 14 being parallel. In the units 2, 3 the roll 10 is replaced by a single small diameter roll 11 or two such rolls, respectively. Over each liquor treatment zone A, . . ,H the flights 15a, 15b of the thread loops make contact with large diameter treatment rolls 16 parallel to the rolls 12, 13, 14. Each roll 16 dips into a liquor trough 17 and makes positive contact at all times with one or two adjacent thread sheets 15 so that each thread loop is treated twice in each zone. At the discharge end of the unit a drying zone K is provided. In the unit 1 the drying machanism may be incorporated in the roll 10 as described in Specification 814,477 and there is no treatment roll 16 in the zone K. Alternatively, if there is no drying mechanism in the top roll or rolls, a final treatment roll 16' is provided and may incorporate a heater as described in the abovementioned Specification. A jockey roll 18 is mounted below the roll 16' and slightly inclined thereto. Thread loops 15' embrace the rolls 16', 18. The roll 16' may be coaxial with the treatment roll set X in which case the leading end of the thread sheet 15 is taken from the roll 13 and wound round the rolls 16', 18 or with the treatment roll set Z in which case the leading end is drawn off the roll 14 and wound round the rolls 16', 18. In an alternative embodiment, Figs. 3 and 4 (both not shown), the roll 14 is situated above the rolls 12, 13 between which the rolls 16 are located. In the drying zone K the thread loops 15' pass over a roll 16' and the apex of the roll 14 and avoid the use of a roll 18, the axis of the roll 14 being slightly inclined to that of the rolls 16. Scraper or doctor blades 19 may be provided to act on the roll 10. The leading and trailing edges of the circumference of each roll 16 may be formed with several short shallow steps 16a, Fig. 5 (not shown), down to a radius just less than the perpendicular distance between the axis of the rolls 16 and the tangent between the roll 14 and either of the rolls 12, 13. Alternatively, the opposite edges of the circumference may be chamfered down to such radius or the entire roll may be "barelled". For treating viscose rayon thread the successive treatment zones may comprise acid setting, then two separate washings, then desulphurizing followed by two separate washings, and then bleaching followed by washing, soaping and drying.