CONSTANT LENGTH THREAD CUTTING DEVICE FOR THREAD TYING UNIT OF OPEN END SPINNING MACHINE

摘要

PURPOSE:To effect tying of threads at an improved percentage of success through improvement of the cut end of the thread, by a method wherein the thread unwound from a package is brought into circular contact with the peripheral surface of a rotary cutter to cut the thread. CONSTITUTION:The middle part of a thread unwound from a package is grasped between the nip formed by grasping rollers 17 consisting of a driving roller 17a and a press roller 17b. The forward end of the thread grasped by the rollers 17 is sucked and grasped by a second suction nozzle 38. Further, said thread is brought into circular contact with the circular surface of a cylindrical rotary cutter 26, positioned between the rollers 17 and the nozzle 38, with the aid of a pivotal actuating arm 28 to cut the thread. This enables the cut end of the thread to be lengthened and tapered toward the end, and besides, fibers are properly untangled, resulting in the ability to effect reliable tying of threads in a spinning rotor and perform tying of the threads with an improved percentage of success.