形成的方法，以及用于监测和维持由在从供给到吸鼓或吸入盘纤维，形成纤维管（44），一个摩擦纺纱装置（37）的装置产生的纱线的预定的纱线质量的装置，从该纱 （37; 81），通过测量前进纱线的机械张力，其特征在于，所述纱线质量被检测到并且该测量的值与规定的电压值相比较，并且，低于或覆盖对应的电压的预定电压容差时增加或spannungsvermindernd上 纺纱设备采取行动。

A method and an apparatus for monitoring and maintaining a predetermined yarn quality of a produced by means of a friction spinning device yarn (37), in which from the supplied to a suction drum or suction fibers fiber tube (44) is formed, from which the yarn is made , distinguished by the fact that the yarn quality by measuring the mechanical tension of the yarn (37; 81) found and the value of this measurement is compared to a predetermined voltage value, and that for shorter stays or overwriting a predetermined voltage tolerance corresponding voltage increasing or spannungsvermindernd on the spinning device is acted.