To make matching of the timings of a sendout part and a takeup part by sensing their rotating motions from time to time, and applying brakes to either of them when their mutual timing goes in disorder.

A drive control device of a collecting machine is composed of encoders 1 and 2 to sense the rotating speeds on the sendout part and a takeup part, respectively, a first low-voltage priority circuit 3 to pick up that of the signals emitted by the encoders 1 and 2 which lies on the low voltage side and to emit it in priority, another encoder 6 to sense the rotating speed of a driving motor for a line shaft, a second low-voltage priority circuit 7 which picks up and emits in priority that of the signal emitted by the encoder 6 and the signal emitted from the first low-voltage priority circuit 3 which lies on the low voltage side when such two signals are fed, and a control part 5 which is fed with a signal on the low voltage side emitted by the second low-voltage priority circuit 7 and executes the control of the driving motor 4 for the line shaft.