Design And Implementation Of Intelligent Milling Tools With Cutting Temperature In-situ Sensing

Nowadays, an increasing number of novel parts with difficult-to-cut materials, thin-wall structures and complex surfaces are adopted in aerospace area. During high speed milling processing of these parts, the high local temperature in the tool-chip interface will lead to some negative effects which variate with time and space. Such as deformation of workpiece, wear of cutting tool and part deflection. The acquisition of cutting temperature is significant for improving the parts' processing quality, the prediction of tool wear, and the fining of cutting models. However, the geometric constraint and rotatory motion of milling cutting system induced great challenges to the accurate sensing of cutting temperature in-situ, as well as real-time communication. In this paper, an intelligent milling tool with cutting temperature in-situ sensing function is designed. It is capable of accurate, constant and real-time acquisition of the cutting temperature. The main research results of this thesis include:In order to solve the problem of incapability in acquiring the cutting temperature in-situ in high speed milling, an intelligent milling tool with cutting temperature in-situ sensing function is proposed. In this milling system, the thermocouple is employed to measure cutting temperature. The power is supplied wirelessly based on electromagnetic induction principle and the on-line temperature data transmission is realized by wireless communication.As for the interference on the wireless transmission system brought by the cutting tool's metal material, mutual equivalent model is used to analyze the influencing factors of the performance of inductively coupled power transfer system. The influence mechanism of eddy is also analyzed. Finite element numerical method was used for simulation. Based on the analysis above, a method of using ferrite shield to overcome the barriers brought by the eddy on shank surface is proposed, and the system parameters which is related to the communication performance is optimized.The hardware and software of the intelligent milling tool system is designed, among which, the performance of wireless power supply system is improved by phase-locked loop tuning technology and synchronous rectifier technology; the near-field coupling communication is realized by amplitude modulation, synchronous detector, and envelope detection technique. Meanwhile, the communication protocol of the system was determined.The experiment platform is built. The performance of wireless power supply system and wireless communication system are tested and analyzed on the platform. The results prove that the transfer rate of temperature data is up to 5kbps and the energy transfer efficiency is up to 62.2%. Finally, a practical experiment is conducted, which verifies the temperature monitor function of the intelligent milling tool.