| 摘要 |
The device (1) has distinct opacity webs (10, 20) that are respectively integrated to mobile and fixed rollers (30, 40), where the rollers are placed parallely against each other. The rollers are connected to each other by a draw bar (50). The mobile roller is displaced directly opposite to a blocking zone by translation along a direction parallel to a deployment direction of the webs. The draw bar and the mobile roller are constituted of mobile units. |
