Feed roller is driven by an electronic frequency converter which permits stepless variation of its speed and is controled to be synchronized with doffer by the computer.

给棉罗拉采用调频电机传动，实现无级变速，通过计算机控制与道夫传动同步。

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The novel ramie MCC included wires for cylinder, doffer and worker roller, which reduced the combed ramie neps and string content by 20% and 25% respectively;

该新型苎麻针布包括锡林针布、道夫针布和工作辊针布。新针布使梳麻麻粒减少20%，并丝率减少25%；

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