Method and device for picture disruption when winding a thread

摘要

The method involves changing frequency between a minimum and a maximum value continuously. The changing frequency is changed during approaching of a pre-determined critical winding ratio such that temporary average value of the changing frequency changes erratically. The changing frequency is changed additionally for the change of the temporal average value such that the distance of the minimum and the maximum value is reduced during approaching of the critical winding ratio and increased after leaving the critical winding ratio. An independent claim is also included for a device for interfering an image during winding a thread on a cross bound bobbin in random coils.