| 摘要 |
<p>The plastic film is provided from a bobbin. In the body of the device is provided, blow the return roller of the sheath, two other rollers placed at a certain distance one from the other and turning on their horizontal axis and parallel and between these two rollers a support with two pairs of pulleys or rollers which press against themselves at points situated above the horizontal plane containing the respective axis of the rollers; the open sheath is passed between these rollers and the pairs of pulleys.</p> |
