Spindle having an underwind crown for ring spinning and ring twisting frames, especially for cord twisting frames

摘要

Spindle for ring spinning and ring twisting frames, especially for cord twisting frames, having an underwind crown arranged coaxially on the spindle below the bobbin and above the whorl, the crown having an extensive sleeve part for the winding-on of a thread during underwinding and an annular rim extending outwardly with recesses at the periphery and adjoining the sleeve part upwardly, from the base of which rim there may project cutting edges of at least one knife. With ring spinning or ring twisting frames equipped with such spindles the ring bank, after a predetermined measured length of thread has been wound on the bobbin, falls to a so-called underwind stop, by which the spindle drive is switched off. The traveller and twisting ring are located at a level at which during decrease of the spindle drive down to standstill of the spindles the thread is no longer wound on the bobbin but is wound on the cylindrical sleeve part of the underwind crown. When the full bobbin is taken off the spindle the thread leading from the bobbin to the windings on the sleeve part of the underwind crown is cut.