PURPOSE: To provide the captioned device capable of always obtaining a beautiful and uniform section by a method wherein a forced drive type belt conveyor device is arranged between an extruder and a cutting machine and synthetic rubber is prevented from laterally spreading by eliminating extruding force of friction.

CONSTITUTION: The forced drive type belt conveyor device 42 is provided between the extruder 40 and the cutting machine 41 and further, the extruder 40 and the conveyor 42 are provided on a common base 43 so that they can move in the direction of the extruding path 44. The base 43 is moved by a cylinder 45 and the destination is fixed by a displaceable stopper 46. The conveyor 42 is composed of a machine frame 48 fixed on th side of the base 43 through a bracket 47, a pair of front and rear wheel bodies 49, 50 supported by the machine frame 48 the belt 51 put between both wheel bodies 49, 50 and a geared motor 52 synchronizing with one wheel body shaft and mounted on the base 43. The synthetic rubber 53 extruded from the extruder 40 is received by the conveyor 42 moving in synchronization with the extruding speed and out.