Abstract: A method of spinning-in yarn on an operating unit of a rotor spinning machine includes steps of yarn preparation for spinning-in, steps of spinning rotor preparation for spinning-in, and final spinning-in steps. The final spinning-in steps include at least the beginning of the sliver supply to the singling-out device, leading of the fibers from the singling-out device away from the spinning rotor for a predetermined time interval, letting the spinning-in yarn end get into contact with the collecting groove of the spinning rotor, and starting of the yarn draw-off and winding. At least some final spinning-in steps are time synchronized in relation to the closing of the spinning unit thus obtaining optimum piecer quality repeatedly at all operating units of the machine.

Abstract: The invention relates to a rotor spinning machine comprising a plurality of operating units situated next to each other, each of which contains a spinning unit (1) with a singling-out device (5) having in its body a rotatably mounted combing roller (52) equipped on its circumferential surface with an operative coating (521) around which there is provided in the body (51) of the singling-out device a circumferential fibre channel (511) whose operative section extends in the sense of rotation of the combing roller (52) from the mouth of the sliver feeding device (4) to the supply channel (6) bringing the singled-out fibres into the rotor, said circumferential fibre channel (511) having provided therein the mouth of a closable auxiliary supply channel (514) for pressure air.

Abstract: The invention relates to a rotor spinning machine comprising a plurality of operating units situated next to each other, each of which contains a spinning unit (1) with a singling-out device (5) having in its body a rotatably mounted combing roller (52) equipped on its circumferential surface with an operative coating (521) around which there is provided in the body (51) of the singling-out device a circumferential fibre channel (511) whose operative section extends in the sense of rotation of the combing roller (52) from the mouth of the sliver feeding device (4) to the supply channel (6) bringing the singled-out fibres into the rotor, said circumferential fibre channel (511) having provided therein the mouth of a closable auxiliary supply channel (514) for pressure air.

Abstract: A method of spinning-in yarn on an operating unit of a rotor spinning machine which comprises steps of yarn preparation for spinning-in, steps of spinning rotor preparation for spinning-in, and final spinning-in steps, the steps of yarn preparation for spinning in comprising at least the detection of the yarn end on the bobbin or the preparation of auxiliary yarn when spinning-in on an empty tube, unwinding and metering a yarn length required for spinning-in, setting the yarn into its spinning-in path on the operating unit of the rotor spinning machine in which the yarn is outside the reach of the yarn distributor and not clamped between the rollers of the draw-off mechanism, creating a spinning-in yarn end and introducing it into the yarn delivery tube from the spinning rotor, the steps of the spinning rotor preparation for the spinning-in comprising at least the opening of the spinning unit to its cleaning position, cleaning of the stopped spinning rotor, closing of the spinning unit, and the final spinning