抄録
One of the methods to examine quality under production of the synthetic yarn and running condition of the equipment is to measure the winding up tension. However, the tension meter commercially available has the defect to dedect the yarn quality as its sensor comes in contact with the yarn.
In the previous report, we analyzed movement of the synthetic yarn caused by the motion of the traverse guide. We reported that the tension was able to be calculated by measuring the propagation speed of the bending wave of the yarn.
In the present paper, we report on the technique and device to achieve non-contact measurement of tension.
The results obtained are as follows :
(1) The measurement value of non-contact tension meter developed in this study is corresponding well by a conventional contact type tension meter in relative evaluation.
Therefore, non-contact tension meter has accuracy equal with the contact type tension meter.
(2) The indication revel of the contact type tension meter is smaller than that of the non-contact type by (Line density) x (Running velocity of yarn) 2, as the former detectrr has the characteristic structurally to take in count the centrifugal force exerted to the yarn bent at the detection guide as equivalent reduced tension though the centrifugal force doesn't affect to the yarn tension at all.
(3) The sensing system is developed to measure the propagation speed of the bending wave of the yarn eliminating the influence of the changes in passing point of the wave across the sensing beam, applying the sudden change property of the reflection angle of beam before and after the pass the sharp wave top generated by sudden reversing of the traverse guide. And so we put non-contact tension meter to practical use.
