METHOD AND DEVICE FOR SETTING THE PRE-TENSION OF BLADES OF A GRANULATING DEVICE

摘要

The invention relates to a method for setting the pre-tension, under which blades (11) of a granulating head of a granulating device lie against the perforated plate (8), said head being carried by a shaft (12) that can be displaced in an axial direction and being driven by a motor (21). The method uses the torque of the motor (21) for this setting operation. According to the method, the shaft (12) is successively adjusted in both axial directions at a constant speed, whereby the course of the torque M of the motor (21) is recorded for both directions over the adjustment path x of the shaft (12). The differential /dx is formed from this course and the position x0 of the shaft is determined for /dx = 0. A position x = x0+xz of the shaft is set (12) with the starting point as said position x0, whereby xz represents the desired adjustment of the shaft (12) towards the perforated plate (8). The device for carrying out said method is provided with a sensing unit (66) for the temporal course of the torque M of the motor (21). The output signal of the sensing unit (66) influences an actuating drive (75) for the displacement the shaft (12). The device also comprises a unit (69) for forming the differential /dx, in addition to a unit (70) for determining the position x0 of the shaft (12) for /dx = 0. Said two units are connected to the actuating drive (75).