| 摘要 |
The process applies tension to a strip of film drawn from a roll, and intersects and deflects the film at a point between the roll, and a user post. Frictional resistance to sliding is generated at this point, causing resistance to drawing and thus causing film tension between the point and the post. The area of the surface generating the frictional resistance is varied to modify the tension. - The resistance is generated over the full width and over a length related to the tension required. The effect may be obtained by passing the film round return gullies on a wheel which is rotated to vary the contact surface. The film may pass round gullies with adjustable lateral offsets, or it may pass over a corrugated curved surface.
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