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Research on Design of CNC Fine-Boring Machine

The boring machine is used for fine boring on ram. The ram, the machining precision of which is about 5μm level, will be used to make another machine tool after processing. To meet the demand about fine boring, the paper studied the boring machine design. Firstly, make the multi-position process simultaneously by arranging three boring tool on the boring bar corresponding to three stations of ram. Secondly, three eddy current displacement sensors are arranged in the same axial position of the boring tool, which measure the change of the inner wall of three round holes. Errors of roundness, concentricity and parallelism will be calculated based on the measured data, also the feed amount of secondary processing is calculated in order to guide the feed of boring tools which are driven by linear motor in closed loop control. Finally, these steps are repeated until the measurement results meet the accuracy requirements.