| 摘要 |
To obtain semifinished products of a satisfactory quality from thermoplastic materials on extruders, the screw 2 must always be filled and operated with a constant torque. For this purpose, arranged in a slanting manner in the feeding container 8 is a slide 10, which can be adjusted in the sense of narrowing or widening the cross section of the charging container 8 by means of a servo motor 16 and drive elements 12, 14 and 15 connected to the latter. The actual torque of the screw 2 is determined via the power consumption of the drive motor for the screw 2 and is compared with a predetermined setpoint torque value which is characteristic of and necessary for the respective working process. The system deviation established controls the servo motor 16 and thereby opens or closes the cross section of the container 8 to a greater or lesser extent by means of the slide 10. As a result, the filling pressure is changed in a simple way, so that it is possible to operate with constant torque independently of the respective apparent density of the material. <IMAGE> |
