Research On Automatic Tool Changer And Fault Diagnosis Of Machining Center Based On PMC

CNC machining center with tool magazines and automatic tool changer is the key equipment of intelligent manufacturing and digital production line construction.When processing products with complex structure and high precision requirements,it can realize one-time clamping and multi-process continuous processing,which plays a vital role in the development of national manufacturing industry.The purpose of this paper is to use FANUC PMC(Programmable Machine Tool Controller)to design the hardware and software of the automatic tool changing device,and to study its fault diagnosis method,which greatly reduces the auxiliary time of product processing,improves the accuracy of fault location and greatly increases productivity.This paper takes gantry four-axis linkage CNC machining center as the research object,introduces the basic structure and working principle of CNC machine tool and PMC,investigates and chooses the types and driving modes of tool magazines and manipulator,determines the use of disc tool magazines,and adopts the random tool changing mode of manipulator,and analyses the tool changing mode and tool changing mode.The overall control scheme of automatic tool change is put forward in the exchange process.The algorithm of tool magazines selection and random tool change and the whole program flow of PMC for automatic tool change are designed.The macro variables and user macro programs are studied,and the user macro program for automatic tool change is designed.After that,the principle of external alarm based on PMC is elaborated,and the whole process of fault diagnosis and fault diagnosis management system related to automatic tool change are designed by combining with typical fault examples in the process of automatic tool change.Finally,on the basis of summarizing the field debugging experience,the debugging process of the automatic tool changer is designed,and the key points such as adjusting the orientation angle of the spindle in the debugging process are described in detail.The results show that after several tool changing tests,the tool magazines is positioned accurately and the random tool changing of the manipulator is realized.The average tool changing cycle is 1.7-2S.The machine can display alarm information in time when the tool changing fails,which is convenient for fault diagnosis.