Patent GB-831549-A (GB)
Title: An apparatus for the manufacture of curled thermoplastic threads according to the false-twisting method
IPC: D02G1/02
Filed: 1957-04-24
Abstract: 831,549. Finishing yarns; spinning and twisting machines &c. ONDERZOEKINGSINSTITUUT RESEARCH N. V. April 24, 1957 [May 14, 1956; March 18, 1957], No. 13103/57. Classes 120(2) and 120(3) [Also in Groups XI and XXXIV] In apparatus for making curled thermoplastic threads comprising a thread supply device, a twist stop, a heating device, a cooling zone, a false-twisting device comprising a rotatably mounted tubular spindle, and a thread discharge device, the spindle is pressed by means of one or more driving belts into two or more "throats" each formed by discs which are freely rotatable around different shafts and may be in similar or different planes and/or be staggered along, and/or overlap in the direction of the axis of, the spindle. A false-twisting device 2, shown in Fig. 1 as one of a series mounted on a frame 1, comprises a grooved tubular spindle 3 having a bracket 5 clamping a perforated sapphire 6 through which yarn 24 travels. The spindle is driven by a belt 8 which may be pressed thereagainst by rollers, as at 9, so that the grooves 4 are maintained in contact with wear-resistant e.g. rubber, rims 10 of discs 11 carried on shafts 12 rotatably mounted on a plate 15 swinging motion of which is limited by engagement of a lug 17 with fixed abutments 18 and 19. When the spindle is moved (by swing- ing plate 15) from the operative position shown, it is retained by hooks 22 carried on a column 21. A modified spindle, Fig. 3, comprises a portion which is engaged by belt 8, portions 27 co-operating with two pairs of discs, as at 11, and abutment rims 30, 31 which engage elastic rims 32 and/ or 33 to support, and/or maintain the position of, the spindle. Axial displacement of the spindle may also be prevented by means of permanent or electro-magnets (see Group XXXIV). The weight of the spindle may be such as to be balanced by the force exerted by the travelling yarn. Each disc 11 may be mounted freely rotatable on a fixed shaft or discs may be secured in pairs on a hub which is freely rotatable around such a shaft. The apparatus shown in Fig. 4 comprises a spindle assembly, inverted in relation to the device of Fig. 1 for false-twisting downwardly travelling yarn, which is sup-' ported by tenons 36 resting in jaws 37 of an arm 38 secured to the machine frame. The part 35 of plate 15, mounts a heating device comprising an insulated tube 54 of resistance material through which yarn passes in vibratory manner and which is electrically heated by passage of current therethrough, feed wires 55, 56, being connected to conductive cross-arms 52, 53: the tube 54 is maintained straight by a spring 51. The plate 15 is urged by a spring 47 into a position in which the spindle 2 is detached from the belt 8, when a tensioning hook 43 is lifted to allow a cam 40 to move thereunder, and may be retained in such position by placing a limiting pin 41 into a jaw 44: the spindle is returned to operative position by lifting hook 43 so that cam 40 may pass under a tensioning pin 42 whereupon plate 15 swings towards belt 8 until arrested by spring 47 and hook 43 is lowered (to a limit determined by pin 41) so that it coacts with cam 40 to press plate 15 ,against spring 47 into a final position maintained by the lower part of cam 40 being arcuate about a pivot shaft 45. A yarn-cooling tube may be mounted (on the plate 15) between the heater and the spindle.