| 摘要 |
<p>PURPOSE:To make the tension of wire constant by obtaining the rotation and rotary position of bobbin through rotary position detecting means provided on the drive shaft, then controlling the brake force applied on the wire to predetermined level prior to the changing of rotation. CONSTITUTION:Pre-tension device 19 applies predetermined brake force to the wire 2 between said device 19 and bobbin 26, and the tension is controlled by the brake reel 21 of electromagnetic brake 20. In other word, counter 28 counts the output from rotary encoder 27 and every time when said level reaches predetermined level it produces three different brake voltages periodically and applies to electromagnetic brake 20 thus to maintain the tension of wire constant by means of tension reel 21.</p> |
