Abstract: A transport system for incrementally advancing cartons in a carton processing machine through a series of work stations spaced along a processing line, the transport system including an endless chain carried by at least two rotatable idler gears, the chain having at least one run parallel to the processing line, arm members spaced along and protruding laterally from the chain, with the arm members along the one run extending across the processing line to contact cartons located therealong, a piston-cylinder unit having a reciprocating piston rod longitudinally movable in opposite directions and a connecting device for selectively connecting the piston rod to the chain during movement of the piston rod in one direction causing the chain and the arm members spaced thereon to be incrementally advanced.