Patent GB-1327273-A (GB)
Title: Process and apparatus for texturizing yarn
IPC: B65H54/54
Filed: 1970-11-06
Abstract: 1327273 Textured yarn; fluid jet false twister UNIROYAL INC 6 Nov 1970 [10 Nov 1969] 52911/70 Headings DID DIF and D1J Apparatus for texturizing synthetic yarn comprises means for supplying yarn at a controlled tension and speed 1, 2; a heating oven 20 including a yarn heating chamber through which the yarn passes from the supply means to an air jet false twisting means 40 having a nozzle assembly 42, which nozzle assembly has an upper yarn receiving element 400, a lower element 460 and a disc in between having slots therein to direct air to provide a whirling stream of air to induce twist in the yarn; an air diffuser 41 having a yarn inlet and outlet, coupled directly to the upper nozzle element 400, whereby the yarn is allowed to balloon in the diffuser 41; a second yarn tension and speed control means 3 to control the tension and speed of the yarn passing out of the lower nozzle element 460. The first yarn tension and speed control means comprises two sets of driven rolls 1a, 2a and separator rolls 1b, 2b, the rolls 2a being driven at a speed faster than the rolls 1a to effect a predrawing of the yarn. The last few turns of the yarn between the rolls 2a and 2b are separated by means of a stationary toothed twist-resisting bar 14. The oven 20 comprises a yarn heating chamber through which the yarn passes, the heating chamber being supplied with heated air directed into the chamber at an angle downwards from the horizontal via inclined ducts which communicate with air heating bores provided in the block forming the oven. The air heating bores are provided with bobbins which fit closely within the bore to provide a limited channel between the bore and the bobbin, this channel being provided with air. The block itself is heated by means of heating elements located in further bores in the block. The airjet false twist means comprises a nozzle assembly which is located in an assembly holder connected to a pressurised air supply. The upper nozzle element 400 comprises a generally cylindrical block with a central frusto-conical bore 412 providing a ballooning zone for the yarn. A sealing ring 423 is provided to seal the nozzle within the holder. The lower nozzle element 460 comprises a generally cylindrical block having a central constricted bore 480, 481. The wall of the lower element forms a skirt portion 462 surrounding a central raised platform 470 on which the disc is located. Air passages 44, 464, 471, 477 and 452 provide the supply of whirling air to twist the yarn in the bore 412. The lower nozzle element 460 is also provided with a sealing ring 468 to seal the element in the nozzle holder. The upper and lower blocks are cut away at 44 to provide communication with the air supply duct in the nozzle holder. The whirling air passes out of the nozzle assembly at 413 into the air diffuser. The tension regulating means comprises a bar pivoted adjacent one end thereof and provided with adjustable weights at the other end thereof whereby the desired tension in the yarn may be predetermined. A disc having two projecting pins at diametrically opposed locations is rotatably mounted on the bar between two further projecting pins, one of which projects through a collar on the bar. The collar is'provided with a slot which engages one of the pins on the rotatable disc. The yarn is passed successively over the pins and any variation in tension causes the bar to rotate to compensate therefor whereby yarn is either fed more freely to the drive roller 3 or less freely. If desired the yarn may be passed through a second oven 90 operating at a lower temperature than the oven 20, but of the same construction. The yarn then passes via rolls 4 to a wind-up mechanism. The wind-up mechanism is preferably provided with a doffing mechanism. The winding spools are supported on drive chucks which in turn are supported by a biassed clutching arrangement to frictionally engage a rotating drive member. Brake and release handles are provided which are manually operated. When the bobbin is supported for rotation, the chuck is expanded by movement of one chuck end relative to the other. A further guide is provided above the traversing yarn guide and a pneumatic circuit is provided for moving the said further guide to transfer yarn from a wound bobbin to the next adjacent empty bobbin. A delay mechanism may be incorporated in the circuit to wind a transfer tail on the bobbin. In a preferred embodiment the bobbin is held on the chuck by coiled circular springs which are expanded by sliding movement of the chuck ends whereby the springs frictionally contact the inner surface of the bobbin. The chuck ends are moved by means of a handle turning on a cam surface whereby springs within the chuck are either compressed or released. Yarn Winding Mechanism. The yarn is guided by traversing elements 120, 121, Fig. 11, that are reciprocated by grooved drums 124. Above the drums 124 is a pigtail 130 that can adopt any of four different settings P1, P2, P3, P4. While the package on spool 103 is being wound the pigtail is at P1. When this package is complete the pigtail moves to P2 to cause the yarn to commence to wind around spool 102. This permits the yarn to form a tail winding on the spool 102 without the yarn being picked up by element 120. After a short pause the pigtail is moved to P3 to cause the yarn to be picked up by element 120 and so cause the yarn to be traversed back and forth. When the package on spool 102 is complete the pigtail is moved to P4 to cause a tie-intail to be wound on a fresh spool 103. When the pigtail moves to P1 the yarn is picked up by guide 121 and a package build up on spool 103 begins. Braking and doffing spools. Fig. 14 shows spool 103 mounted on a spindle carrying coil springs 419a, 419b that are wedged between the spindle and the spool. The spool 103, or the yarn package thereon, is driven by frictional contact with a drive roll. The handle 404 can be moved to any of three settings to cause a cam surface 510 that is movable with the handle to co-operate with any of three cam surfaces 520, 521 and 522. In the first setting, see Fig. 14, the coil springs 419a, 419b grip the spool 103 and a brake surface 414 is non-operative. In the second setting of the handle 404 the stationary brake surface 414 engages rotary brake surface 555 to stop the spool 103. In the third setting of the handle 404 the sleeves 408, 420 move apart to permit the coil springs 419a, 419b to contract radially and so permit the package to be doffed by sliding it to the right off the spool 103. Pressing package against drive member. In Fig. 11a the spool 102 is mounted on a bar 112 slidable in bearing 117. A weight 114 tensions the system and presses the spool 102 against the drive drum 101.