Design of a multiple station combined automatic drilling machine

LI Yi-dong1， YAN Si-jie1， LIAO Li-bo2， YANG Zi-jian3
（1. School of Mechanical Science & Engineering， Huazhong University of Science & Technology， Wuhan 430074， China；
2. School of Civil Engineering & Mechanics， Huazhong University of Science & Technology， Wuhan 430074， China；
3. Ningbo Saivs Machinery Co.， Ltd.， Ningbo 315135， China）

Abstract： Aiming at the processing errors and efficiency problems caused by multiple clamping positioning which exists in machining of a circular hole and threaded hole，a project for the design and research of multiple station combined automatic drilling machine was established. DVP-ES2 programmable logic controller（PLC）was used as the core controller of the control system in order to control the AC servo system and the frequency control system. RS485 communication network based on MODBUS-RTU protocol was designed to create a high-speed and stable communication network system. Human machine interface（HMI）was used to set parameters and monitor status. Four tools were designed for the combination of different manufacturing procedures. The operation results show that the maximum positioning error of tools has 0.1 mm，the repeated positioning error of tools has 0.02 mm，the threaded holes processed by this drilling machine are normal，this drilling machine runs stably and can meet the basic processing requirements.
Key words： multiple station combined automatic drilling machine； MODBUS-RTU； AC servo control； PLC