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AssigneeW. Schlafhorst AG & Co.
InventorsRolf Haasen, Heribert Kargel, Hans-Gunter Wedershoven
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A method for removing both long and short yarn defects at the winding heads of a bobbin winding machine. Following the appearance of a yarn defect, the length of the defective yarn between the time of the appearance of the defect and the time of a subsequent yarn cut is determined. A suction tube is positioned in front of the winding bobbin to aspirate the defective yarn therefrom. The yarn is unwound, the entry of the yarn into the suction tube is determined by means of a sensor disposed therein, and the yarn length unwound from the winding bobbin and entering the suction tube is determined. The unwinding process is stopped at the time when, on the basis of the detected length of defective yarn, a sufficient yarn length has been aspirated into the suction tube so that, upon subsequent insertion of the yarn from the winding bobbin into the yarn end connecting device, the yarn length wound since the appearance of the yarn defect remains outside of the yarn end connecting device for the purpose of being cut and discarded.
A method for removing defects from a traveling yarn being wound from a delivery bobbin onto a winding bobbin at a winding head of a bobbin winding machine, comprising the steps of monitoring the traveling yarn for defects and, when a yarn defect has been detected, interrupting the winding process by cutting the yarn downstream of the detected defect thereby forming an upper yarn with the defect extending to the winding bobbin and a lower yarn extending from the delivery bobbin, stopping the winding bobbin, determining the length of the upper yarn wound onto the winding bobbin between the time of the detection of the defect and the time of making the yarn cut, rotating the winding bobbin in an unwinding direction for a predeterminable number of revolutions to unwind therefrom the defect of the upper yarn, aspirating the upper yarn unwound from the winding bobbin into a suction tube thereat, sensing the presence of the upper yarn within the suction tube, stopping the unwinding of the upper yarn when the determined yarn length has been aspirated into the suction tube, inserting the aspirated upper yarn from the winding bobbin into a yarn end connecting device with the yarn defect disposed outside of the yarn end connecting device to be cut and discarded, inserting the lower yarn from the delivery bobbin into the yarn end connecting device, splicing the upper and lower yarns while cutting and removing the defect of the upper yarn, and then restarting the winding process.
Dependencies are inferred from the claim text.