already passed through the processing units 5 6 7 8 10 11 and 14 which are successively arranged in its path within the takeup device 20 the suction device 25 takes in the yarn 36 and removes it to a waste container for threading the yarn 36 same is first manually guided by means of a suction gun 35 once the yarn 36 is threaded in processing units 5 6 7 8 and 10 it is inserted by means of suction gun 35 into a guide groove of yarn guide 29 shown in phantom lines this concludes the threading procedure by an operator the subsequent threading of yarn 36 as far as the takeup device 20 occurs automatically to this end the actuator 30 moves the yarn guide 29 in the direction of the suction inlet 33 of heater 11 in this process the yarn 36 enters the range of suction of suction inlet 33 at the same time the cutting blade 31 of the cutting device cuts the yarn end advancing between suction inlet 33 and the held suction gun 35 the yarn 36 now advances in guide tube 12 to blow outlet 34 the yarn 36 that is ejected from guide tube 12.