Rieter

General

Index

Package change on automated rotor spinning machines is actuated when the preset length of yarn or package diameter is reached. Electronic length measurement is so accurate that variations in yarn length from package to package are maintained in a very narrow tolerance range, usually of +/- 0.5%. Mechanical diameter cutout is less accurate, since package diameter and thus the yarn length wound up can vary due to differing winding conditions at the individual spinning positions (differences in thread tension, slippage, etc.).

Automatic package change has been solved by different conceptual approaches. Whereas in one system removal of the full package and spinning start-up on an empty tube are performed in a  single operation (integrated automation), in another case removal of the full package and subsequent spinning start-up are performed in  two separate operations by two robots working independently. Spinning is started on an empty tube, but using a starter package pre-wound at the end of the machine. Although all manufacturers of automated rotor spinning systems now offer the integrated automation system, a large number of machines, also newer ones, are in operation worldwide with operating robots working independently. Both systems will therefore be described in more detail.