Patent ID: 8096698

Claim:
A load monitoring method for a kneading apparatus including a screw shaft, the screw shaft having an input shaft portion to which is transmitted power from a motor and being adapted to knead a material to be kneaded, the load monitoring method comprising: detecting loads on the input shaft portion by a load detector provided in the input shaft portion of the screw shaft; averaging the detected loads over a predetermined time section to determine a load mean value and calculating a difference between a maximum value and a minimum value of the loads in the time section to determine a load amplitude value; determining that the load on the screw shaft is in a normal condition when the thus-determined load mean value and load amplitude value lie within a predetermined normal range, or determining that the load on the screw shaft is in an overload condition when the thus-determined load mean value and load amplitude value do not lie within the predetermined normal range; in case of the load on the screw shaft being in the overload condition, integrating the time of maintaining the overload condition as an overload duration time; in case of the load on the screw shaft being in the normal condition, resetting the overload duration time; and when the overload duration time exceeds a set time, performing at least one of issuance of an “abnormal” alarm and stop of rotation of the screw shaft.