关键词: HSK刀柄, 临界转速, 可靠性, 接触应力, 高速切削

Abstract:

The connection performance of HSK toolholder and spindle has great influences on machining accuracy and security of CNC machine tools. In viewing this, given the crucial fact that the HSK toolholder/spindle connection may encounter failure at high rotational speed, a contract stress model on the HSK toolholder/spindle junction surface was built at any rotational speeds. And the results of finite element analysis
have good uniformity with this model. By using this stress model, considering the influence of clamping force and magnitude of interference, the computational model of critical rotational speed based on the HSK toolholder and spindle connection and the interface reliability were established. With the computational model of critical rotational speed, an accurate calculation of the critical rotational speed was attainable. And the influence of clamping force and magnitude of interference on critical rotational speed was also discussed. The interface reliability at any rotational speed can be accurately calculated and the relationship between rotational speed and interface reliability was found according to the interface reliability mode. The establishment of the two modes is meaningful to prevent the HSK toolholder/spindle interface failure and guarantee machining accuracy and security of CNC machine tools. Meanwhile, it also provides a theoretical foundation for the reasonable utilization, optimization of parameters and reliability design of the HSK tool-holder.

Key words: HSK tool-holder, critical rotational speed, reliability, contract stress, high speed cutting