Calculation method for bending deformation of complex structured tools based on subcomponent method

Abstract

Increasingly, new structures are being incorporated into the design of engine components to satisfy the aircraft pursuit of the high thrust-to-weight ratio. As machining requirements surpass the capabilities of traditional structured tools, there is the growing trend towards the design and application of tools with complex features, such as tapered or arcuate structures. In actual machining, issues such as decreased machining accuracy and deteriorated surface quality caused by the deformation of such tools still exist widely. Traditional computational methods fall short in providing accurate calculations for the deformation of such specialized tools, due to the complexity of their structure. Based on the generic multi-parameter model of the tool structure and the subcomponent method, this paper proposes the calculation method for bending deformation of milling tools, tailored to complex structured tools. The Generic Multi-Parameter Tool Model (GMPTM) that represents the overall structure of the tool is developed using the Automatically Programmed Tools model as the foundation. Guided by geometric features, the tool is subdivided into subcomponents according to the GMPTM. By combining the approximate differential equation of the cantilever beam deflection curve with the boundary constraints between subcomponents, the overall bending deformation equation of the tool is obtained by assembling the deformation equations of the subcomponents. The derivation processes for the bending deformation equations are provided respectively for the tool arbor subcomponents (cylindrical, tapered and arcuate) and the tool body subcomponent. To ensure the accuracy of deformation calculation, an equivalent diameter calibration method for the tool body subcomponent based on experimental deformation data is proposed. The analysis of experimental results for seven different tool shapes, combined with the comparison to existing computational methods, confirms the reliability and applicability of the bending deformation calculation method for complex-structured tools, offering the effective solution to address deformation challenges in such tools.