Determination of tool setting point and tool change point The tool setting point is the starting point of the movement of the tool relative to the workpiece in CNC machining. When programming, whether the tool moves relative to the workpiece or the workpiece moves relative to the tool, the workpiece is regarded as stationary, and the machining center tool is moving. The tool setting point is usually called the program origin, which can be set on the part to be processed (such as a point between the center of the positioning hole of the part and the surface of the machine tool table or fixture), or it can be set at a fixed size relative to the positioning reference of the part. A certain position on the fixture in relation to the arm drilling machine (for example, a cylindrical pin or hole is specially designed on the fixture, etc.). Its selection principle is easy to align; programming is convenient; tool setting error is small; inspection is convenient and reliable during processing.
During tool setting, the tool setting point should be coincident with the tool position point. The so-called tool position point refers to the positioning reference point of the tool. For various end mills, the intersection of the tool axis and the bottom end face of the tool is generally taken, and the drill bit is taken as the drill tip.
The tool change point is set for the programming of multi-tool machining machines such as machining centers and CNC lathes, because these machine tools automatically change tools in the middle of the machining process. In order to prevent parts or fixtures from being damaged during tool change, the tool change point is often set outside the machined part, and there must be a certain amount of safety.
Determination of the processing route The feed route is the trajectory and direction of the movement of the tool relative to the workpiece to be processed during the exponential control processing. In the process of CNC machine tool processing, the determination of the processing route of each process is very important, because it is directly related to the machining accuracy and surface roughness of the workpiece. The feed route not only includes the content of the processing technology, but also reflects the sequence of each working step. The feed route is one of the basis for writing programs. Therefore, it is best for the machining center to draw a process diagram when determining the feed route, and draw the already drawn feed route (including the feed and retract routes), so that Can bring a lot of convenience.