基于plc的钻床电气控制系统设计

Abstract:This design is to study the design problem of the electriccontrol system of Z3040 drilling machine commonly used in machining.The aim is to realize the working process:press the start button,theworkpiece is clamped,the pressure relay is ON after clamping,and thetwo drill bits start working at the same time.When the depth is set by thetwo limit switches,the two drills go up at the same time,and stopascending when going up to the starting position set by the two limitswitches.After both positions are in place,the workpiece is rotated by acertain angle,the limit is ON,and the current value of the counter isincreased by 1.After the rotation is finished,the second hole is drilledagain.After all the holes are drilled,the current value of the counter isequal to the setting.Value,when the workpiece is released,when therelease is in place,the limit switch is ON and the system returns to theinitial position.The traditional relay-contactor electrical control systemhas the problems of complicated circuit,poor reliability,fault diagnosisand troubleshooting.Because PLC electrical control system is comparedwith relay-contactor electrical control system,it has a series ofadvantages such as simple structure,convenient programming,shortdebugging period,high reliability,strong anti-interference ability,lowfailure rate and low requirements on working environment.The design ofthe electrical control system of the Z3040 drilling machine for theprogrammable controller was developed,and the hardware and softwaredesign of the electrical control system was completed,including theselection of the PLC model,the allocation of the I/O port,and the I/Ohardware wiring diagram.Drawing,PLC SFC chart and ladder programdesign,because there is no real thing,also carried out the simulationcircuit design.The working process of PLC controlled drilling machine iselaborated.The method of replacing the traditional relay-contactorelectrical control system with PLC to improve the working performanceof the machine is discussed.The corresponding control schematic isgiven.Key words:programmable controller;drilling machine;electrical controlsystem;ladder diagram