Analysis Of Reliability And Sensitivity Of Radial Tool Double Servo Toolholder

At present,CNC machine tools occupy an important position in the automotive,shipbuilding,bridge,aerospace and other industries with its processing capability for mechanical parts.As a key part of the CNC machine tool,the servo tool holder is the main guarantee for the CNC machine tool to complete a variety of machining modes and high-precision machining.When the servo tool holder is used to cut the workpiece at high speed,the tooth surface stress on the triple tooth gear indexing device and the vibration of the entire tool post may be caused resonance problems.The reliability and machining accuracy of the tool holder are both Have a significant effect.This paper studies the reliability and sensitivity of a typical tool holder structure radial knife-out double servo tool holder,and mainly carries out the following work:(1)The background and significance of the reliability and sensitivity analysis of the power servo toolholder are introduced.The development and research status of numerical control machine tools,power servo tool holders,artificial neural networks and reliability theory are summarized.(2)Firstly,the rigidity reliability and sensitivity analysis of the triple toothed plate is carried out.The triple toothed plate is a key component in the radial knife-out double servo blade holder and is also an important guarantee for the accuracy of the knife holder indexing.Before the reliability analysis of the triple toothed plate,it is necessary to establish a parametric model and perform static analysis.Therefore,a parametric finite element model of the triple toothed plate is established,and the tooth profile angle and the inner and outer diameter of each tooth plate are used as random parameters.For subsequent analysis.The finite element static analysis of the triple toothed plate was performed to find out the tooth surface stress of each tooth plate.At the same time,the influence of the change of the above parameter pairs on the tooth surface stress was studied.(3)Considering that the rigidity reliability analysis of the triple toothed plate requires a large amount of sample data as a basis,the Isight experimental design is used in combination with the finite element static analysis results to generate a large number of test sample data to fit the tooth profile angle,internal and external tooth plate The relationship between the diameter of the tooth plate and the tooth surface stress.Next,using BP neural network technology to obtain the mathematical expression of the above functional relationship,and then combine the stress-strength interference model to establish the reliability limit state equation.Then using the perturbation method to solve the triple tooth plate stiffness reliability and the sensitivity of each random variable value.(4)Consider the influence of the excitation frequency of the radial knife-out double servo toolholder on the reliability of the tool holder system in the cutting process,so the frequency and sensitivity of the tool holder are analyzed.In the same way,parametric modeling of the whole tool rest is first performed,and multiple dimensional parameters and material parameters in the model in the model are defined as random parameters.The modal analysis of the entire tool rest is performed to obtain the natural frequency of the entire tool rest.The corresponding mode shape.(5)Because of the excessive number of parameters in the complete tool model,the influence of changes in some parameters on the natural frequency of the complete machine is relatively small.Therefore,the parameters in the entire tool model are screened,and the filtered parameters are analyzed.The influence of 10 parameters on the natural frequency of the complete machine.Next,the neural network was used to fit the relationship between the 10 parameters selected in the model and the first order natural frequency of the tool rest,and the frequency reliability limit state equation of the tool rest was then established to complete the radial ejection.The Calculation of Frequency Reliability and Sensitivity of Double Servo Blade System.