Motorized spindle accelerated life testing time design method

Abstract

The invention belongs to the technical field of numerical control machine tool and relates to a motorized spindle accelerated life testing time design method. The method includes the steps that firstly, product load data and fault information are collected; secondly, a load distribution model is established; thirdly, a program load spectrum is designed; fourthly, a product service life estimated formula is determined on the basis of the Miner fatigue accumulation damage theory, and an accelerated life testing accelerating factor model is built on the basis of the formula; fifthly, based on the fault information, a first fault time reliability mode is built through model hypothesis, parameter estimation and hypothesis testing; sixthly, testing time design is conducted on the basis of the first fault time, the first fault time corresponding to an acceptable reliability degree serves as a standard, and a relational model of motorized spindle testing time and the sample capacity is established; seventhly, an accelerating factor is considered for testing time design, and the creditability of the testing time design is verified. The relational model of the testing time and the sample capacity is considered, the accelerating factor model is established on the basis of the modification Miner theory, the modeling accuracy is improved, and the method better conforms to actual conditions.

Description

technical field [0001] The invention belongs to the technical field of numerical control machine tools, and relates to a design method for the accelerated life test time of an electric spindle, in particular to the establishment of a relationship model between the test time and sample size of an electric spindle, the Miner fatigue cumulative damage theory and its correction, the establishment of a program load spectrum, and the accelerated life The test acceleration factor model is constructed, and on this basis, the acceleration factor is considered to design and calculate the test time of the electric spindle of the machine tool, and its reliability is verified. Background technique [0002] The electric spindle is a key component of the machine tool system, and its performance and reliability level determine the machining accuracy and production efficiency of the entire machine tool to a large extent; the reliability test is to obtain fault information, fault data and cond...

AI Technical Summary

Problems solved by technology

For example, Liu Hanwen et al. used the designed electric spindle test bench to simulate the load spectrum of the real working condition through the loading system, and used the power as the accelerated stress to carry out the electric spindle loading test under constant stress. However, compared with the step stress accelerated life, the test The sample failure is slow, and the sample size required is large; Zhu Dexin, Chi Yulun, etc. assumed that the life of the machine tool spindle obeys the Weibull distribution and the characteristic life of the machine tool spindle and the test load satisfy the inverse power law equation, and establish a fixed number censored Constant stress accelerated life test model, but in the actual test, the product is subject to complex effects of various stresses, it is difficult to establish a realistic accelerated model to represent the relationship between life characteristics and stress levels; Siew-Leng Teng and Kwee-Poo Yeo hypothetical life - The stress curve obeys the logarithmic linear relationship, establishes the fixed-number truncated step stress accelerated life test model, and proposes the least square analysis method of the step stress accelerated life test, which obviously simplifies the derivation process of the test program design, but in the electric spindle In the life test of high-reliability products, there are often only very few failure data, and there is a lack of sufficient test data

Images