The conveyor has a drive mechanism, contained in a cage (15), having connections (24,25) for the channel under which it is fixed. The drive mechanism is attached by a guide block to the conveyor element. The drive mechanism is connected to the guide block by a vertical arm. The cage consists of a drive cylinder head and rectangular base plate (16,17) and screw connection (18,19) is the form of a coaxial tie bar in each corner of the plates. The plates have connections (21,22) for the cylinder`s propellent.