Method of quickly identifying thermal state characteristics of machine tool main shaft

Abstract

The invention discloses a method of quickly identifying thermal state characteristics of a machine tool main shaft, which comprises the following steps: arranging n temperature measuring points on the machine tool main shaft, obtaining temperature values of the n thermometry points in each time under sampling interval Delta t, and obtaining temperature sampling matrix with sampling time m; setting delay time to determine thermal eigenvalue b r (r=1, 2, ..., p); choosing a point with highest temperature in temperature testing points as a key point, and calculating an expression of a temperature rise curve of the key point; calculating root-mean-square error Sigma of a temperature measured value and an estimated value; and obtaining root-mean-square errors Sigma with different sampling time m until the root-mean-square error exists a minimum root-mean-square value. Therefore, a temperature rise curve of a key point corresponding to the minimum root-mean-square value is the curve which can accurately reflect the thermal state characteristics of the machine tool main shaft. According to the method, only about 30 min is required to realize the purpose of quickly identifying the thermal state characteristics, acquire the temperature rise curve of the key value, and shorten the identification time; the result is accurate; the operation is simple.

Description

technical field [0001] The invention relates to the field of identification methods for machine tool thermal characteristics, in particular to a method for quickly identifying the thermal characteristics of machine tool spindles. Background technique [0002] With the continuous development of machine tools in the direction of high speed and high precision, thermal errors have an increasing impact on machining accuracy, and even machining errors caused by thermal errors account for about 75% of the total error. How to effectively reduce the thermal error has become the focus of research. At present, there are mainly three methods: one is to reduce the temperature change, which can be carried out by strengthening cooling, controlling the ambient temperature, and preheating before processing; the other is to reduce the sensitivity of the machine tool structure to temperature changes. It adopts symmetrical structure design, uses materials with low thermal expansion coefficient...

AI Technical Summary

Problems solved by technology

Although the thermal error experimental device of the machine tool under the load condition of the simulated working condition makes the thermal error of the spindle very close to the actual working condition, the test method for the thermal characteristics of the machine tool spindle has not been improved, and there are still problems of time-consuming and laborious

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