Accumulation roller is special arranged to meet the requirement of goods accumulation. The difference to driven roller is the connection type between driving head and roller itself. The ordinary driven roller is fixed connection, the accumulation roller is movable connection. Accumulation transportation is also called piled transportation. It has not only the function of common drive transportation, but also the feature that goods stop and pile up on the conveyor line in the condition of driving element still operating, while the operating resistance is not obviously increased. In normal conveying, the accumulation device transmit the moment of force. But when goods stopped and piled up, the operating moment of resistance exceeds the roller’s definitive working moment of force, the accumulation sleeve or friction slice slips, roller and driving element are in the condition of flexible connection. It appears that rollers under the goods stop running, only the driving element is steel running.