| 摘要 |
Directly below the upper roller carriage (18), a lower roller carriage (36) is provided which is firmly joined to the housing frame (6) and, during welding, forms a unit supported only on the material (3, 4) being welded. The rollers (20, 21; 44, 45) are driven by a central geared motor. The heated wedge (10) and the knurled welding rollers (20, 21; 44, 45) are in each case provided in the centre part of the roller carriages. They can be offset in order to produce a double welded seam with a test channel lying in between. The heated wedge is retracted into the housing (16) when it is not to contact the webs. During the lining of structures (for example tunnels) plastic webs (3, 4) supported on uneven surfaces must be welded. This is made possible by the supporting of the two roller carriages (18, 36) on the movable housing frame (6). For welding, the springs (13), via the rollers (14), press the webs (3, 4) against the heated wedge (10) and the springs (32), via the rollers (20, 21), press the webs against the rollers (44, 45). The rollers (20, 21) can be lifted by means of the handles (33, 34). <IMAGE> |
