Hole skewness is a key technical index of NC deep hole drilling quality. In the actual production, the machining requirements of parts are higher and higher, and the CNC deep hole drilling puts forward higher technical requirements for hole deflection. Especially deep holes. Controlling the amount of deflection is particularly important. The main factors that affect the straightness of the deep hole axis are the symmetry of the cutting edge and the guiding condition of the drill.
Therefore, improving the symmetry of the cutter and choosing a longer guide are the main means of improving the straight line of the deep hole axis. The surface of the machined parts is uneven and skew, which has great influence on the straightness of the deep hole axis. As the deviation occurs during drilling, the drilling will be intensified and the deviation will be larger. Therefore, it is necessary to check carefully at any time.
In the normal process of die machining, with the deepening of drilling, the drilling torque of the cutter is basically unchanged, and the power of the motor is also fundamentally unchanged. When the tool is damaged, the torque of the tool will increase, and then the motor current will increase. After the analog input module of PLC, the analog signal will be detected and converted into digital signal. The operation function of PLC is compared with the set value to determine whether the tool is damaged.
The analog output port of the speed regulating device is used to transform the detected current signal into 0 ~ 10V voltage signal, which is output to the analog input module of PLC for a / D analog-to-digital conversion, and then compared with the set value. This setting value is obtained by the technologist according to the parameters such as workpiece raw materials, cutting tools, machining volume, etc., and selected by the drawing section switch. When the detection value is greater than 20% of the set value, it is concluded that the torque is overloaded, that is, the tool is damaged, the PLC announces an alarm, stops processing, replaces the tool, and the workpiece deep hole processing.