| 摘要 |
The subject of the invention is a machine for wrapping vertical and top surface of loads (13) with stretchable film. The machine of the invention is provided with a swinging film tension setting unit (22) connected to the end of a shaft (6), which unit has pre-stretching rollers (7A) provided with a pre-stretching motor (20), a leading roller (7B) containing an arm provided with a roller (7C), a tension setting pneumatic cylinder (16) provided with an analogous displacement transducer (17) and equipped with a piston provided with a magnet (16A), furthermore a pressure regulator (18) and a frequency changer (15) all fastened to a frame of the film holding and pre-stretching unit (23), wherein the film winded off from the film reel (7) is led between the pre-stretching rollers (7A), one connected to another with a transmission (19) and one of them is driven by a pre-stretching motor (20) then the film is led around the leading roller (7B) having the arm rotating around a center of rotation and provided with the roller (7C), it is connected to the piston provided with the magnet (16A), which is mounted in the tension setting pneumatic cylinder (16), the latter is provided with the analogous displacement transducer (17) and the piston provided with the magnet (16A) is connected to the pressure regulator (18) and the. frequency changer (15), which frequency changer (15) is connected also to the pre-stretching motor (20). |
