This paper deals with a new method for an adaptive control of cylindrical plunge grindings. A workpiece with high accuracy can be obtained in a conventional grinding method since finish timings of each grinding stage (rough grinding, fine grinding and spark-out grinding) are determined by a high accuracy sizing gage. However, this method often results in low grinding efficiency and low integrity of workpieces. These problems are caused by the fixed finish timings of the fine grinding stage and the spark-out grinding stage. In this study, a method based on variable timings is introduced. The timings are determined depending on a size generation curve which is calculated on the basis of the measured data of the workpiece diameter in the fine grinding stage. These results are instantaneously fed into an NC computer on the grinding machine and the grinding process is adaptively controlled for various grinding conditions and various workpieces. As a result of some experiments, it has been cleared that the proposed method is valid to the variation of the depth of grinding in the rough grinding stage, the variation of the velocity ratio and the structural stiffness, while there is some room for further study to the grinding of a workpiece with soft property.
