Analysis of Tool Setting Skills in CNC Machine Tool Processing

The mastery of tool setting skills in CNC machine tool processing can improve the accuracy of tool setting operations and pave the way for high-quality finished parts processing. The tool setting skills of CNC machine tools are mainly the measurement and input of tool offset data and the determination of the starting point.

　　 (一) Measurement and input of tool offset data

　　 In order to explain the measurement and input of tool offset data relatively accurately, the author takes the CNC lathe HCNC-1 as an example. In fact, in the actual CNC machine tool processing, the selection requirements of the tool setting method are not very strict, because the product processing accuracy requirements are not very high, the tool setting method can be selected more arbitrarily. At present, the following methods are usually used to perform tool setting operations in HCNC-1 CNC machine tool processing with tool setting skills, and to measure and input tool offset data.

　　1 Direct observation method

　　 The method of direct observation is that the system is completed manually. The specific implementation steps are: First, according to the tool setting position given by the system, manually align the reference knife on the reference point. (As shown in Figure 1). Secondly, clear the XY coordinates in the system. Thirdly, the reference knife is retracted by an electric method. Fourth, select a suitable tool for component processing, and again move the tool to the reference point by inching forward. At this time, the computer screen will display the data of the tool position deviating from the reference point. Finally, input the deviation data displayed on the screen into the offset data parameters, and the tool will automatically adjust the position so that the tool is at the reference point position, so that CNC machining can be carried out in an orderly manner.

　　2 How to accurately position the reference knife

　　 The specific steps for measuring and inputting tool offset data by accurately positioning the reference tool are as follows: First, select the reference tool and exit it along the X axis. At this time, Z will be displayed on the computer screen. The coordinate value of the axis, record it. Then record the value displayed by the knife exiting along the Y axis at one end of the outer ring. Secondly, set the reference knife at the Z-axis coordinate value and the Y-axis coordinate value to clear the XY coordinate in the system. In this way, the reference knife is set at an accurate position.

　　3 The method of accurate positioning

　　 Use accurate positioning to measure tool offset data. Input, the first part is that the system uses the reference tool to cut the outer diameter of the workpiece in the electric mode. After that, the reference knife is withdrawn along the Z axis by jog, and at the same time, the outer diameter of the surface of the north car is measured, which is D1, and the X axis coordinate value displayed on the computer screen is recorded. Use the reference tool to cut the end face of the workpiece, and then make the reference tool exit along the X axis, and also record the outer diameter L1 and Z coordinate value Z1 of the north car surface. Replace the tool required for component processing and repeat the above operation, after which the deviation value of the tool and the reference tool, namely X, Z, will be displayed on the screen. Finally, the deviation of the two knives is calculated. What needs to be explained here is that if the system is set to diameter programming, the two tool deviation calculation methods are:

　　△X2u003dX2-X1-(D2-D1)

　　△Z2u003dZ2-Z1-(L2-L1)

　　 If the system is set to radius programming, the deviation calculation methods of the two tools are:

　　△Xu003dX2-X1-(D2-D1)/2

　　△Zu003dZ2-Z1-(L2-L1)/2

　　 Note: 1# tool is the reference tool, and 2# tool is the tool used for component processing.

　　 (2) Determination of the starting point

　　 For the determination of the starting point, the following three methods are usually used: (1) Set the center of the flat end surface as the reference point, and align the tip of the selected tool with the reference point to make the starting point accurate , Can carry out numerical control processing operation. (2) Taking the quarter point of the flat end surface as the reference point, first use the reference tool to perform cross-section one-cut operation exit and the outer circle one-cut operation exit. When selecting the tool used for component processing, place it at the flat end surface quarter point, so The starting point can be determined for CNC machining. (3) Taking the quarter point of the flat end surface as the reference point, the precise tool setting records the data displayed on the screen each time the reference tool exits, and the processing can be done directly to the corresponding coordinates.