| 摘要 |
PURPOSE:To detect the temp. abnormality of a bearing with good accuracy, by comparing the temp. rising ratio of the bearing and the evaluation temp. rising ratio thereof and judging the temp. abnormality of the bearing when the temp. rising ratio of the bearing became higher than the evaluation temp. rising ratio thereof. CONSTITUTION:In the embodiment of an upright type water wheel dynamo, the temp. of a thrust bearing and that of cooling water are measured by the resistance thermometer provided to an inlet side and the temp. rising ratio D of the bearing is shown by formula I as the function of bearing evaluation temp. thetax, wherein the correction of the temp. of cooling water was added to the temp. of the bearing, on the basis of the measured temp. Then, the temp. thetax is operated according to the formula I to operate the rising ratio D. Further, an actual temp. rising ratio dtheta/dt is operated. Next, the rising ratio D is compared with the rising ratio dtheta/dt and, when dtheta/dt becomes larger than D, an abnormal alarm is emitted. By this method, the detection of the temp. of the bearing can be performed with good accuracy. |
