| 摘要 |
PURPOSE:To make very-low tension load applicable without complicating the structure by installing a moving sheave mounted with multiplicate sheaves different in diameter on the concentric circle, and a shift sheave for changing an acting diameter of this moving sheave and varying the position of a fine wire, respectively. CONSTITUTION:A very fine wire W at the first pass goes past a finest diametral moving sheave 14a and, after once being wound by a fixed guide sheave 16, it is put back to a large diametral moving sheave 14b via a shift sheave 17 and wound with the second pass, and thus it goes by way of the large diametral moving sheave 14b from the smaller diametral sheave 14a, whereby tension to the very fine wire W becomes smaller in proportion to the sheave diameter. Since a tension setting load value for a moving sheave shaft 13 is able to give a larger load value than a target tension load value of the very fine wire W, the very low tension for the fine wire W is easily secured without making the structure of a tension adjusting mechanism 11 into precision and exquisiteness. |
