| 摘要 |
<p>The yarn is advanced by passage between a driven frusto-conical roller, and a parallel frusto-conical idler roll pressed against it. A yarn guide moves the yarn towards the small or large dia. ends of the rollers to adjust the yarn advance rate in dependence on yarn tension. Pref. the guide is carried on a vertical pendulum spring biassed towards the smaller dia. ends and the yarn is drawn from the guide such that the yarn tension moves the pendulum towards the large dia. end. Increase in yarn tension moves the guide towards the large dia. end to increase the advance rate, whilst decrease in yarn moves the guide under the action of the spring to the small dia. end to decrease the advance rate.</p> |
