Rotor spinner sliver insertion - is automatic with inner underpressure and mechanical sliver opening and external monitoring of fibre delivered from new sliver end

During the automatic feed of new sliver into a rotor spinning machine, simultaneously or in succession there is an underpressure applied to the end of the sliver from the interior of the spinning unit and a mechanical drawing-in and sliver opening action. The vol of fibres sepd from the sliver end and sucked into the spinner is controlled externally until it is registered that a sufficient fibre vol from the end of the sliver has been achieved. Pref within the suction tube (30) a transmitter to monitor the volume of fibres sucked through from the end (19) of the sliver is connected to the control unit (25) of the splicing appts through an evaluation unit (34). An air permeable sieve (27) is within the inner cross section of the suction tube (30) to trap loosened fibres. Outputs are at the suction tube (30) in front of and behind the sieve (27), linked to a measurement unit evaluation system (34) in the control function (25). The sieve (27) is fitted to a distorting section within the section tube (30), connected to the transmitter. The transmitter is also connected to an indicator at the evaluation unit (34). A delay is in the programe controlled system to delay the removal of the suction tube (30) from the entry opening (23) of the exhaust channel (22), after the underpressure action has been stopped, in order to extract the fibres from the transmitter in the collection channel of the suction exhaust (24). ADVANTAGE - The technique gives a sliver insertion action, even after a number of attempts, without requiring a spinner cleaning procedure and without applying force to the sliver.