Development Of A Reliability Testing System For CNC Lathe Power Servo Turret And Exeriment

The present domestic research and development of CNC machine tools inaccuracy, speed, large scale and multi-axis linkage and so on has made significantprogress, the gap with abroad mainly embodied in the reliability of CNC machinetools, especially the reliability of the essential functional component of CNC machinetools, and the essential functional component of the domestic due to the frequentbreakdowns, low level of reliability has become the focus and emphasis of the userand the machine tool enterprises, also is the current domestic CNC machine toolindustry leading level of the development of the bottleneck to the world. At presentdomestic enterprises and accessories for CNC lathe machine console power servo toolholder reliability test system, only stay in idle or lay particular stress on experimentwas carried out, due to the dynamic servo turret in actual working condition will beaffected by the effect of dynamic cutting force and torque, so a separate idling or layparticular stress on test to simulate the actual working condition.Taking AK33100D type power servo turret as the research object, in thelaboratory building power servo turret reliability test system, through the early datacollected in field reliability test, laboratory reliability test plan formulation, thedynamic cutting force and the torque load test in lab, in a short period of time tocollect the failure data of dynamic servo turret, and failure analysis and reliabilityassessment, provide experiment basis for product improvement.This article main research content is as follows:(1) Study the structure of power servo turret and the actual working condition,with reference to relevant national and industry standards, development ofelectro-hydraulic servo dynamic cutting force loading and electric eddy currentdynamometer torque load power servo turret reliability test system. In order to meet angles of the dynamic force, we will design the support device of electro-hydraulicservo dynamic loading, which has five degrees of freedom, and adopt the XY mobileplatform to quickly realize the connection between the power head and dynamometer.(2) Monitoring and control of reliability test system analysis and design,monitoring test object dynamic performance parameters of the power servo turret,monitoring of electro-hydraulic servo dynamic cutting force loading and electric eddycurrent dynamometer torque load state;Control system including PLC control therevolve of the servo motor and the power head of servo motor operation,measurement and control instrument control the electric eddy current dynamometertotorque load, etc.(3) Introduction to the classification of the reliability test and consider the threefactors from the reliability definition, before the experiment, clear terms definition,the principle of fault judgment, counting and sampling principle, according to theproposed field reliability test plan and method for the reliability test, and the field testdata processing, as to provide theoretical basis for carrying out reliability test of thelaboratory.(4) To introduce power servo turret for revolving test in the laboratory, dynamicloading test and torque load reliability test process and test requirement, based on theconclusion from laboratory reliability test failure. Bayesian method is adopted toestablish the modeling of Mean Time Between Failure(MTBF), according to a prioriinformation, evaluate the dynamic servo turret and put forward the improvement planfor an appear fault.