17 driving the delivery device 11 alterations in sliver delivery after the roller pair 14 are recorded by the sensor 12 and communicated by means of a signal 18 to the control 13 so that by means of the signal 16 the motor 17 has its speed varied in accordance with the change in output a novel feature provided by the invention is that the control 13 has a computer attachment which is indicated in purely diagrammatic form by the reference 19 and which responds to the operation of a switch to be described hereinafter by decreasing card output in accordance with either fig2 or fig3 further operation of the same switch accelerating the card in the manner shown in fig2 and 3 the decrease in output and the acceleration cause a change in the position of loop 20 of the sliver 21 which the card 10 produces and which the device 11 delivers into a can 22 this change in the position of the loop 20 produces corresponding signals 18 so that the delivery device 11 i e motor 17 thereof either slows down or accelerates the device 11 correspondingly this feature provides the advantage that no additional synchronization between the card motors and the motor 17 driving the device 11 is required fig5 is a plan view of the card 10 and delivery device 11 and also shows the sliver loop sensor 12 like.