| 摘要 |
PURPOSE:To measure winding diameter or circumferential speed of a new reel accurately by sticking a bar code for detecting circumferential speed which also serves as a both sides adhesive tape onto the surface of the new reel then detecting the bar code through an optical sensor. CONSTITUTION:A both sides adhesive tape 2 printed with a bar code is sticked in the central section of a new reel 1. The bar code is read out through an optical sensor 3 and ON/OFF signals are fed to a control circuit so as to calculate circumferential speed and winding diameter and detect real change timing. Since the length of a section to be detected through the bar code 2 is set constant and the circumferential speed and the rotary speed can be calculated based on the time required for passing through the section, radius of reel can be obtained. After paper is added, reel speed and radius can be detected based on the line speed and the rotation thus ending the roll of the bar code 2. Consequently, fluctuation of tension due to differential circumferential speed can be reduced during past time. |
