微铣削中考虑刀具跳动的瞬时刀具挠度变形研究

Study on Instantaneous Tool Deflections Considering Tool Run-out in Micro Milling Process

基于对将刀具跳动(包括轴线偏移跳动及轴线倾斜跳动)的影响考虑在内的微铣削力的研究,提出一种新的微铣削加工过程中刀具挠度变形解析计算方法,在微铣削加工刀具挠度变形理论模型的建立过程中,以微立铣刀为例,将微立铣刀假设为连续的铁木辛柯梁(Timoshenkobeam)并采用刀具工件切削接触区域内沿刀具切削刃方向作用于切削刃离散微元上的分布微铣削力载荷取代作用于刀尖位置的总微铣削力。此外,为获取微铣削加工过程中的刀具挠度变形具体数值,设计并搭建包括x轴及y轴两方向电容式传感器的测量系统,并通过实验对所提出的微铣削加工过程中考虑刀具跳动的刀具挠度变形理论模型进行对比验证和分析,验证所提出模型的正确性,并为进一步研究微铣削加工过程工件表面质量及参数优化提供理论依据。

According to the micro milling forces considering the influence of tool run-out(axial offset and tilt),a new mathematic method of tool deflections is proposed in the micro milling process.In the theoretical model of tool deflections in micro milling operations,the micro flat end mill is assumed as a continuous Timoshenko beam,and the distributed cutting forces acting on the discrete elements along the cutting edge direction have displaced the total cutting forces acting on the tool tip.Moreover,in order to obtain the values of tool deflections in micro milling operations,the measuring system including the capacitance sensors in the x-axis and y-axis directions is designed and set up.Then,the measured and predicted tool deflections can be compared and analyzed to validate the accuracy of the proposed theoretical model.The proposed model of tool deflections provides the theoretical foundation for further study on surface quality and parameters optimization of micro milling process.