16 bush 42 is only then pressed upwards counter to the spring tension of spiral spring 43 when bush 24 has reached its bottom end position thus when the start of the winding material 29 will be inserted in recess 28 the segments 17 19 are in the vertical position 20 and at that time side flange 13 is not yet in the position shown in fig4 then side flange 13 is pushed into the position shown in fig4 whereby clamping means 32 clamps the start of the winding material 29 only cylinder 11 fig1 holds flange 13 in this clamping position whereby the force of spring 43 pushes down the bush 24 of the side flange 5 against the force of spring 27 the drawings show an embodiment which can be modified in such a way that the bush 24 is operable in a completely independent manner from the removal of the second side flange 13 by means of a special drive this drive can be a pneumatic cylinder which axially displaces bush 24 this pneumatic drive can also act on shaft 26 which can be rigidly connected to bush 24 in this case the shaft 26 must be axially displaceably passed through the side flange 15 so that the drive for the winding process would act on the flange represented in hatched form in fig2 such a construction with a separate drive for bush 24 would have the advantages that the already wound winding material would still be firmly placed on the winding core when second side flange 13 was removed and could be tied there prior to ejection during.