1. Analyze the advantages of five-axis machining
In five-axis machining, flat-bottom end mills are used to maintain the straightness of the messy mold processing surface, which can greatly reduce the processing time. The principle of the five-axis machining center is also suitable for side-face milling with a viewpoint appearance, which can eliminate rib-like lines caused by the processing of the ball end mill, making the appearance of the mold more aspirational, and reducing the need for finishing the mold appearance Increase the workload of manual milling and manual operations.
After five-axis machining skills, the problem of repositioning the workpiece in the cluttered view point requiring multiple debugging and mounting can be solved, not only shortening the time, but also greatly reducing the error that occurs. The tooling fixture required when installing the workpiece The large amount of cost has also been saved, and the machine tool has also achieved the processing of messy parts, such as the drilling, taper processing, and cavity recesses required for messy appearance, which are not possible with traditional methods.
The tool used in five-axis machining is relatively short. At the same time, the processing of the entire part can be completed at one time. There is no need to reinstall the card or choose the longer tool required for the same five-axis machining. The production of the mold is completed internally, and the quality of the appearance of the parts is also better.
2. Analyze the application of five-axis machining center in car mold processing
At present, the design of car parts mainly uses the CAD system, and the design of the parts is completed through reverse engineering and various experiments. The CAM software is used to process the messy appearance of the mold. However, how to ensure the accuracy of design and processing depends on CNC machining, the author analyzes the relationship between the use of the five-axis machining center in mold processing and the quality of car molds.
Processing of deep cavity molds
The process of making car molds is side by side. If a five-axis machining center is used to process deep cavity molds, it is necessary to lengthen the tool holder and tools to complete it. However, when using a five-axis machining center to process relatively deep and steep cavities, you must The better process conditions of the mold processing invention can pass the additional rotation and swing of the workpiece or the spindle head, which can shorten the length of the tool appropriately, and then prevent the occurrence of collisions between the tool, the tool holder and the cavity wall, and reduce the processing time. The jitter and breakage of the tool, the service life of the tool has been extended, and the appearance quality and processing power of the mold have also been greatly improved.
Mold sidewall processing
For the machining of the side wall of the mold, the tool length of the five-axis machining center is greater than the depth of the side wall, and the tool length is determined by the depth of the side wall. If the length of the tool is increased, its strength will be significantly reduced. 3 times the diameter makes the knife phenomenon occur, and the quality of the workpiece will be difficult to ensure. For example, the five-axis machining center can be used to process the side wall of the mold. The spindle or the swing of the workpiece can be used to make the tool and the mold side wall appear straight. When milling the mold side wall, a plane milling cutter can be used to improve the quality of the workpiece. And extend the service life of the tool.
Mold flat surface processing
When processing the flat surface of the mold, the five-axis machining center needs to use a ball cutter to finish milling to obtain a good appearance quality. In this case, it is necessary to increase the tool path, but the center rotation speed of the ball cutter tool is almost zero. In the mold processing, the degree of tool damage is relatively large, the service life of the tool will be shortened, and the appearance quality of the mold will also deteriorate. The five-axis machining center is used to process relatively flat curved surfaces, and the tool can be placed on the workpiece to a certain point of view and then the workpiece can be processed. This can increase the relative linear velocity between the workpiece and the ball nose tool, and not only can the tool life be improved Improvement, the appearance quality of the workpiece will also greatly improve.
Machining irregular surface of mold
Regarding the machining of molds with irregular curved surfaces, it used to be completed by five-axis machining centers. The direction of the tool cutting mold is to move along the entire path of the cutting. The cutting process will not change. At this time, the cutting condition of the tool tip The perfect quality of each part of the mold cannot be ensured. For example, molds with frequent curvature changes and molds with deeper grooves can be processed by a five-axis machining center. The cutting tool has always been able to achieve the best cutting conditions, and the tool can maximize the direction of the entire processing path. , And the tool can also move in a straight line together, and every part of the surface of the mold will be more perfect.
Processing of different shapes of molds
When using a five-axis machining center to process a mold with a three-dimensional curved plane, the cutting of the mold is always protected in the best working condition. The point of view of the tool work can be changed in the arbitrary area of the machine tool, and then the geometry of the die is completed. Processing.
Machining of inclined holes on the inclined surface of the mold
When processing the inclined hole of the mold inclined surface, the five-axis machining center can be used to move the head of the swing-head machine tool to place the spindle on the vertical side of the inclined surface of the workpiece and position it at the accurate hole position. To accurately process the oblique hole on the mold, at least two linear axis interpolation motions are required, and the accuracy of the hole position is also significantly reduced in this process. For processing oblique holes, such as a five-axis machining center with a pendulum table, the action is to place the oblique surface of the mold in an orientation perpendicular to the spindle through the pendulum table. To improve the accuracy of the hole.
Milling of straight lines without direction change of mold
If you want to mill a straight line with no change in direction, you only need to draw a straight line on the tip of the tool. If the direction needs to be changed, the tip of the tool draws a curve, and the direction of the tip of the tool is changed. This curve is necessary to compensate, and it is extremely important to use a five-axis machining center. If the control system does not consider the length of the tool, the tool rotates around the center of the axis, and the tip of the tool cannot be fixed, and it is very likely to move out of the current working position. However, the system of the five-axis machining center has five-axis control. Function. In the operation of processing molds, even though the direction of the tool is changed using the five-axis control system, the orientation of the tool tip can be maintained. In this process, the necessary compensation movement of the xyz axis is also automatically calculated. , At this time, the processing accuracy is significantly improved.
In short, in mold processing, the use of a five-axis machining center can avoid tool interference, and can process messy parts that are difficult to process by ordinary three-axis machine tools. For processing ruled surface molds, you can choose side milling one-cut molding skills , The processing quality is good, and the power is also high. Regarding the three-dimensional profile, especially the large-scale flat surface processing, it can be processed by the large-diameter end mill end close to the large-scale surface. The number of passes will be reduced, the remaining height is small, and the processing power and surface quality can be effectively improved. . Multi-process and multi-face machining can be performed on multiple surfaces of the mold at one time, which improves the processing power and can also effectively improve the accuracy of the orientation of each surface. When using a five-axis machining center to process molds, the tool can always be in the most useful cutting condition for the workpiece. In some processing fields, large-scale tools can be used to avoid mutual interference. The rigidity of this tool Better, the processing accuracy and processing power can be improved. Therefore, the five-axis machining center has wide processing adaptability and is worthy of being widely implemented.