| 摘要 |
<p>PROBLEM TO BE SOLVED: To automatically measure the thickness of a tape wound on a reel. SOLUTION: A tape transporting means comprising a capstan 20, a pin roller 22, a servo motor 24 and a transportation control means 26 transports a magnetic tape 12 at a constant speed V while drawing out the magnetic tape 12 from a supply reel 10. A cycle-measuring means 28 measures a rotation cycle of the supply reel 10. An operation means 30 calculates the thickness D of the magnetic tape 12 on the basis of the rotation cycle Ts of the supply reel 10 measured by the cycle-measuring means 28 at a first time point and the rotation cycle Te of the supply reel 10 measured by the cycle-measuring means 28 at a second time point later by a time Tw from the first time point according to an equation D=V(Ts<2> -Te<2> )/(4πTw).</p> |
