A method for measuring the geometric error of the rotary axis of a five-axis machine tool with one-time clamping

Abstract

The invention proposes a one-time clamping measurement method for geometric errors of rotating shafts of a five-axis machine tool. Through the measurement of the deviations between the postures of two ideal kinematic chains and actual postures, the method calculates geometric error values of a to-be-calibrated kinematic pair on the two kinematic chains based on a spatial error model of a mechanism through inverse computation. The method can achieve the one-time clamping continuous measurement of twelve geometric error parameters of the two rotating shafts of a single-swinging-head - single-rotating-table five-axis machine tool, avoids the multiple clamping of a measurement instrument and a test piece under the condition of guaranteeing the measurement precision, improves the measurement efficiency, and fills a gap of the field. The method can be used for the measurement of the geometric errors of the two rotating shafts of the single-swinging-head - single-rotating-table five-axis machine tool.

Description

technical field [0001] The invention belongs to the calibration technology of machine tools, in particular to the technical field of geometric error measurement of five-axis linkage machine tools. Background technique [0002] Five-axis linkage CNC machine tools are currently the only means to solve the processing of complex parts such as impellers, blades, marine propellers, heavy-duty generator rotors, steam turbine rotors, and large diesel engine crankshafts. The geometric error of the machine tool is one of the main reasons for the machining error of the parts. [0003] Our country has made great progress in the key technology of five-axis linkage numerical control, and has been applied in a certain range in the industrial field. However, there is still a certain gap between domestic five-axis linkage CNC machine tools and foreign advanced levels in terms of high-speed, high-precision, and intelligent performance. In particular, the gap in machining accuracy is more ob...

AI Technical Summary

Problems solved by technology

The geometric error measurement and compensation method of the three-axis linkage CNC milling machine (linear axis) is mature, while the five-axis linkage machine tool has a more complex structure and more geometric error components due to the introduction of the rotating axis

However, for the situation that the geometric error is distributed on different kinematic pairs of two kinematic chains (double kinematic chain geometric error), if the layout of the measuring points and the measurement method in the published literature are still followed, it is impossible to measure the two kinematics at the same time under the premise of one clamping. A kinematic chain provides a sufficient number of measuring points

Therefore, the one-time clamping measurement method suitable for the geometric error of a single kinematic chain is not suitable for the measurement of the geometric error of a double kinematic chain

On the other hand, among the measurement methods for the double-turntable structure in the published literature, only Ibaraki and Mayer respectively proposed a one-time clamping measurement method, while other methods require multiple clamping measurement instruments, that is, temporary layout during the measurement process. In order to obtain a sufficient number of measuring point coordinates at different positions, it can be seen that even the measurement efficiency of single kinematic chain geometric error has not received widespread attention, and the measurement of double kinematic chain geometric error is even less. Related achievements

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