GB1244896A - Apparatus for storing and winding discontinuously and reversibly moving tape - Google Patents

Abstract

1,244,896. Automatic control of tape drives. J. P. ENGEL and M. WICHOUD. Sept.5, 1969 [Sept. 6, 1968], No.44141/69. Heading G3R. In apparatus for reversibly driving tape past a reader between driven spools, the speeds of the spools are electronically controlled by voltages dependent on the lengths of loop between the tape drive and the spools to correct changes in these lengths, and by voltages dependent on the radii of the outermost turns of tape on the spools to compensate for changes in the radii. In Fig.1, a tape carrying information for the control of a knitting machine may pass in either direction between spools 2 and 3. The information is read by a head 17 through which it is driven intermittently by a stepping motor, synchronized with the knitting machine, engaging sprocket holes in the tape. A further stepping motor, also synchronized with the knitting machine, drives a drum 5 engaging sprocket holes in the tape on either side of head 17. A flexible coupling between drum 5 and its drive makes movement of the drum continuous despite the stepping of the motor. Between drum 5 and each of the spools, which are separately driven, loops of tape formed by multiple pulley systems are extended by spring urged levers 12 and 13 which also operate potentiometers 22 and 23 having equipotential end portions. Further levers 8 and 9, spring urged into engagement with the outermost layers of tape on the spools, operate potentiometers 19 and 20. The speed of each spool driving motor is automatically controlled, through a transistorized follow-up speed control system, in dependence on the speed of the knitting machine and the positions of potentiometers 19, 22 or 20, 23. The arrangement is such that, as the tape builds up on a spool, potentiometer 19 or 20 decreases the speed of the spool, and if the speed of the knitting machine or the spools changes, or the loop lengths vary on reversal due to inertia, potentiometers 22 and 23 vary the speeds of the spools in such sense as to tend to restore the loop lengths to normal.