With the acceleration of industrialization, the machinery manufacturing industry is also developing. CNC machine tool technology has made great progress under the influence of technological development. Tool setting plays an important role in CNC machining. As the tool setting process is a technical activity, strengthening the understanding of common operation problems in the tool setting process can provide guarantee for improving the tool setting quality, so as to improve the manufacturing quality of CNC machine tools.
When machining a tool, the position of the starting point of the tool position in the workpiece coordinate system needs to be determined by the tool setting. The specific position of the workpiece in the machine tool coordinate system is mainly determined by positioning and clamping. The basic principle of tool setting can be analyzed from the following points.
1. Machine tool and workpiece coordinate system the origin of workpiece coordinate system is generally set or the origin of workpiece itself. A point on the workpiece can be arbitrarily selected as the coordinate origin according to the actual situation. In order to ensure the close connection between the machine tool and the workpiece coordinate system, the actual positioning of the workpiece origin and the relationship between the part positioning dimensions can be determined. The coordinate origin of the machine tool coordinate system has been determined as early as the machine tool manufacturing and cannot be changed arbitrarily. In order to ensure that the tool holder and worktable can return to the mechanical origin every time in the process of simulation graphics and fault repair of NC machine tool, the operator must manually return to zero to ensure the normal operation of machine tool coordinate system.
2. Firstly, decompose the tool setting operation steps to determine the specific position where the tool setting point coincides with the position point. The starting point of the relative movement between the workpiece and the position point is also the tool set point for part machining, and the position point is mainly used as the reference point. Pay attention to the selection of tool set points: first, whether the programming sequence is simple, whether the mathematical processing is convenient, and the error should be minimized for inspection; Second, the reference point of the machine tool needs to have a certain relationship with the programming origin. Before starting the operation, manually reset the coordinate axis to zero to establish a new machine tool coordinate system; Finally, the command of the input NC code should reflect the workpiece coordinate system and the specific position of the position point. Only when the tool position point is clear, can the original position of the tool point be found.
1. Analysis of tool setting methods there are two main tool setting methods. One is the tool setting tool outside the machine tool. It is more often used in CNC milling machines, that is, the tool holder is installed on the lathe. Carry out rectification work outdoors and install it directly on the machine to work normally. The second is to set the tool on the machine tool, which is more commonly used in turning CNC machine tools. The tool can be directly fixed in a certain position.
2. Method analysis of trial cutting method the main feature of trial cutting method is that the tool setting efficiency is relatively low, but less equipment is required and the method is relatively simple, so the economical type is more commonly used. The trial cutting method also includes two forms. One is the absolute trial cutting method, which determines the deviation of tool position directly or indirectly according to the tool compensation value of other tools; The other is the relative trial cutting method, which only needs a measuring tool to measure the position of the tool. After aligning the working face of the positioning block with the tool position, move the tool until the tool is at the position of the set size. The workpiece size is measured effectively, and the tool setting size is calculated by using this formula.
1. Determination and analysis of tool setting point position when performing the tool setting process of CNC machine tool, the tool setting point position must be clear first. This is the basic content of tool setting operation. Generally, the tool set point is determined by the origin of the workpiece coordinate system, but in actual operation, it needs to be determined according to the actual situation. The position of the tool set point can be a point away from the origin of the workpiece coordinate system or a point on the coordinate system. We should strengthen positioning and make the follow-up work proceed smoothly.
2. When dealing with the problem of tool setting of ordinary NC machine tools, the judgment of tool setting accuracy should be strengthened. The processing of tool setting accuracy can improve the machining quality. Therefore, in the process of accurate problem processing, the debugging of tool setting instrument must be strengthened to improve the accuracy of tool setting operation. In order to improve the accuracy of tool setting, we should first strengthen the understanding of tool setting instruments, master the operation procedures and avoid errors in operation. Secondly, we should strengthen the understanding of the precautions in the operation of the lever dial indicator, clarify the operation procedures, and control the operation contents within a reasonable range. Finally, it is necessary to strengthen the maintenance of precision instruments. Pay attention to control the measurement environment and measurement intensity. At the same time, pay attention to avoid dust pollution of the instrument, improve the accuracy of the instrument and reduce the problem of tool setting.
In short, strengthening the understanding of common CNC machine tool setting problems can provide appropriate solutions for tool setting problems. Because the tool setting operation of CNC machine tools needs a certain degree of technology, the tool setting operators of CNC machine tools need to strengthen their understanding of relevant knowledge. Through correct operating procedures and appropriate tool setting methods, the tool setting process can be improved and the problem of CNC machine tool calibration can be solved.