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In addition to the investment in the machine itself wood mold five-axis machining center, it is necessary to upgrade the CAD/CAM system software and post processor to adapt to the requirements of the five-axis machining; it is necessary to upgrade the calibration program, so that it can be simulated on the entire machine.
A-axis and C-axis such as XYZ three linear axes to achieve linkage,
Automotive tire mold five-axis machining center can be processed out of the complex spatial surface, of course, this requires high-grade numerical control system, servo system, and software support. Machine tool is a symbol of a country's manufacturing level.
In line with the new direction of the development of CNC machine tools
In recent years, international and domestic machine tool exhibitions show that the five-axis machining center software training, CNC machine tools are moving towards high-speed, high-precision, composite direction. But the general worktable can not be designed too large, load-bearing is also small, especially when the A-axis rotary greater than that is 90 degrees, the workpiece cutting will bring a lot of bearing force on the worktable
Moment. The center of the table is also equipped with a rotary table, rotating around the Z-axis, defined as the C-axis, C-axis are 360-degree rotation. In order to achieve the "Tenth Five-Year Plan" development goals, the parts of the urgent need to further develop CNC machining technology, the urgent need to configure a large number of various types of process equipment, especially CNC machine tool equipment.
Now, it is widely believed that the five-axis linkage CNC machine tool system is the solution to the impeller, blade, marine propellers, heavy-duty generator rotor, turbine rotor, large diesel crankshafts and other processing of the only means.
From 1999, in the CIMT, CCMT and other international and domestic machine tool expositions, first of all, the domestic five-axis CNC machine tool products have debuted, the domestic five-axis CNC machine tool market gradually opened, followed by international machine tool giants come in droves, five-axis CNC machine tool varieties and the number of rising year by year: CIM
T99, CCMT2000 were launched CIMT2001 International Machine Tool Fair, Beijing First Machine Tool Factory and Guilin Machine Tool Co., Ltd. respectively exhibited a spindle speed of 10,000r/min five-axis high-speed gantry machining center, Beijing Institute of Mechanical and Electrical spindle speed of 15
000r/min five-axis high-speed vertical machining center; Tsinghua University and Kunming Machine Tool Co. Ltd. jointly developed XNZ63,
five-axis machining center for casting molds adopts the structure of scale Stewart platform, which can realize six degrees of freedom linkage; Dalian Machine Tool Works self-developed tandem-parallel machine tool
DCB-510, whose numerical control system was developed by Tsinghua University, the machine tool realizes the linear motion of X, Y and Z axes through parallel mechanism, and the tandem mechanism realizes the linear motion of X, Y and Z axes. Linear motion by parallel mechanism to achieve X, Y, Z-axis, A, C-axis rotary motion by the tandem mechanism, thus realizing five-axis linkage, and its linear fast feed speed of up to 80m/min. even the developed industrialized countries, but also not a high degree of attention. Interested in military friends may know the famous "Toshiba incident": the end of the last century, □□□□ Toshiba sold to the Soviet Union a few five-axis linkage CNC milling machine, the results of the Soviet Union for the manufacture of submarine propellers, up a few notches, so that the U.S. between the butterfly ship's sonar can not listen to submarines, so the U.S. to the Toshiba company. violated the policy of embargo on strategic materials and wanted to punish Toshiba. Therefore, whenever people in the design and development of complex surfaces encountered can not be solved when the frustration, often turn to help five-axis CNC system.
The other is to rely on the vertical spindle head slewing. Why has five-axis CNC technology failed to become widely available for so long? Five-axis CNC machining because of interference and tool position control in the machining space, its CNC programming, CNC system and machine structure is far more complex than the three-axis machine tools. So that through the combination of A-axis and C-axis, fixed in the workpiece on the table in addition to the bottom surface, the remaining five surfaces can be processed by the vertical spindle. In recent years, following the rapid development of China's national economy and the needs of national defense construction, the high-grade CNC machine tools put forward an urgent massive demand. The development of China's machine tool industry, the use of their own research and development of high-precision, cutting-edge products to intervene in international competition, breaking the international technological monopoly, the international machine tool giants do not want to lose China's potential to dig the market, so flocked to the door, their products "to the door": foreign pavilions **** exhibition of five-axis machining center 8 units, Five-axis turning and milling machining center 1, 5-axis CNC tool grinder 5. Recently, the international machine tool industry has emerged as a new concept, that is, universal processing, CNC machine tools both turning and five-axis milling processing. At present, five-axis CNC technology in the world
The following topics are prevalent. Vertical five-axis machining centerThis type of machining center has two ways of rotary axis, one is the table rotary axis. The goal of composite is to use a single clamping on a machine tool to complete most or all of the cutting process to ensure the positional accuracy of the workpiece and improve processing efficiency. Users need to change the tool frequently or adjust the cutter size of the tool when performing CNC machining, according to the normal processing procedures, the tool trajectory should be sent back to the CAM system to recalculate. Musical instrument five-axis machining centers currently popular CNC systems are unable to complete the tool radius compensation, due to the ISO file does not provide sufficient data to recalculate the tool position. Nowadays, three-axis machine tools attached to a rotary axis is basically the price of an ordinary three-axis machine tool, this kind of machine can realize the function of multi-axis machine tools. However, in recent years, following the computer-aided design (CAD), computer-aided manufacturing (CAM) system has made a breakthrough in the development of a number of CNC companies in China, such as Sunstar, have launched a five-axis linkage of CNC machine tool systems to break the closure of the foreign technology to occupy the high point of this strategic industry, and greatly reduce the cost of its application, so that China's equipment manufacturing industry has ushered in a brand-new era! Information technology as the representative of the development of modern science on the equipment manufacturing industry has injected a strong impetus, but also put forward stronger requirements for it, and more highlighted the machinery and equipment manufacturing industry as a carrier of high-tech industrialization in promoting the whole society to improve technology and industrial upgrading of the irreplaceable role of the foundation. At present, the application of five-axis CNC machine tools is still limited to aviation, aerospace and related industries. These machine tools have reached the international advanced level, reflecting China's machine tool industry for the development of cutting-edge defense industry to provide equipment for the strength of the breakthrough progress. Cylindrical milling cutter for contact forming milling, the need for different diameters of the tool to prepare different programs. Expansion of five-axis linkage function in the machining center, can greatly improve the machining capacity of the machining center, to facilitate the further integration of the system. As the national economic growth and technological upgrading of the driving force to five-axis linkage as a symbol of the machinery and equipment manufacturing industry will be accompanied by high-tech and emerging industries and the development of the **** with the improvement. Five-axis CNC machine tools at home and abroad, the actual application shows that its processing efficiency is commensurate with the two three-axis machine tools, and can even completely eliminate the need to invest in certain large-scale automated production lines, greatly saving the space and workpiece in the different manufacturing units of the turnover between the transportation of time and expense.
Development of five-axis CNC technology in the sea and market analysis
Five-axis linkage CNC machine tools, electric power, shipbuilding, aerospace, high-precision instruments and other civil and military industries and other parts of the urgent need for pivotal processing equipment. And on behalf of the machine tool manufacturing industry is the highest level of five-axis linkage CNC machine tool system, in a sense, reflects the state of a country's industrial development level.
Decades, people generally thought that five-axis CNC machining technology is the only means of processing continuous, smooth, complex surfaces. The table set on the bed can rotate around the X-axis, defined as the A-axis, and the A-axis generally has a working range of +30 degrees to -120 degrees. China is not only to be the world's manufacturing power, but also to be the world's manufacturing power! It is expected that in the near future, following the popularization and promotion of five-axis linkage CNC machine tool systems, will certainly lay a solid foundation for China to become the world's most powerful country!
Machining center is generally divided into vertical machining center and horizontal machining center, vertical machining center (three-axis) the most effective machining surface only for the top surface of the workpiece, horizontal machining center with the help of rotary table, can only complete the workpiece of the four-sided processing. Three-axis machine tools only linear coordinate axes, and five-axis CNC machine tool structure in various forms; a unified section of the NC code can be obtained in different three-axis CNC machine tools on the same processing results, but a certain type of five-axis machine tool NC code can not be used for all types of five-axis machine tools. Western developed countries have long imposed an embargo on our country. The international five-axis NC technology as a national production equipment automation level of the logo. This design also has a major advantage: we use the spherical milling cutter processing surface, when the central line of the tool is perpendicular to the machining surface, because the apex of the spherical milling cutter line speed is zero, the apex of the workpiece cut surface quality will be very poor, the use of the spindle slewing design, glass fiber reinforced plastic trimming five-axis machining centers to make the spindle relative to the workpiece to turn an angle, so that spherical milling cutter to avoid the apex of the cut to ensure that a certain line speed, can be improved! Surface processing quality. CNC programming in addition to linear motion, but also to coordinate the rotary motion of the relevant calculations, such as rotary angle travel overhaul, non-linear error checking, tool rotary motion calculations, etc., dealing with a large amount of information, CNC programming is extremely abstract. But so far, the application of five-axis CNC technology is still limited to a few well-funded parts, and there are still unresolved setbacks. Because of its special status, especially for aviation, aerospace, military industry's important impact, as well as the complexity of the technology, the western industrial developed countries have
The five-axis CNC system as a strategic material for the implementation of the export license track system, the embargo imposed on our country. At present, high-grade machining center is moving towards the direction of five-axis control, five-axis linkage machining center has a high efficiency, high precision features, the workpiece once clamped to complete the processing of five faces.
China's CNC technology and its equipment in the various industrial parts of the application of the overall level is still low, compared with the industrial developed countries a big gap. This leads to the entire machining process is very inefficient. Because the five-axis linkage CNC machine tool system is very expensive, coupled with the NC program production is difficult to make the five-axis system is difficult to "cloth" application.
Development and promotion of the difficulties and resistance in the
Obviously, people have long been familiar with the five-axis CNC technology and the importance of the superiority. Once people in the design and manufacture of complex surfaces encounter unsolvable frustration, they will turn to five-axis machining technology. For the main technical requirements of CNC machine tool equipment is multi-axis, high-speed, good rigidity, power; the number of coordinates of the demand for three to five-axis linkage-based.
Acquisition of machine tools requires a large investment
Previously, the price difference between five-axis machine tools and three-axis machine tools was very large.
Tool radius compensation problem
In the five-axis NC program, the tool length compensation function is still effective, but the tool radius compensation is invalid. As early as the 1960s, foreign aviation industry production began to use five-axis CNC milling machine.
Equipment manufacturing industry is the cornerstone of a country's industry, which provides an important means for the development of new technologies, new products and modern industrial production, is an indispensable strategic industry. Five-axis machining training foreign CNC boring and milling machines, machining centers to adapt to polyhedral and curved surface parts processing, are using multi-axis machining technology, including five-axis linkage function. The advantage of this setup is that the spindle processing is very flexible, the table can also be designed to be very large, airliners huge fuselage, huge engine shell can be processed in this type of machining center. Thus, the study of five-axis CNC machining technology on the national scientific and technological strength and the progress of the comprehensive national power is of great significance.
The ultimate solution to this topic depends on the introduction of a new generation of CNC control systems that are capable of recognizing workpiece model files (such as STEP, etc.) or CAD system files in a common pattern. In particular, during the period of the Dark War, a closure embargo was imposed on China, the former Soviet Union and other socialist camps.
Five-axis linkage CNC is the most difficult and widely used technology in CNC technology, which integrates computer control, high-function servo drive and precision machining technology, and is applied to high-efficiency, precision, and automated machining of complex surfaces. For the pivotal part of the complex shape of the industry, such as aviation, electric power, shipbuilding, mold manufacturing, etc., its production part of the multi-axis machine tool requirements for a larger proportion of the new five-axis CNC machine tools accounted for about 70% to 80% of the total number of CNC machine tools. In order to achieve high accuracy of rotation, high-grade rotary axis is also configured with a round scale feedback, indexing accuracy are within a few seconds, of course, this type of spindle rotary structure is more complex, the manufacturing cost is also higher. For a long time, the United States as the leader of the Western industrial developed countries,
Car tire mold five-axis machining center has been five-axis linkage CNC machine tool system as an important strategic materials, the implementation of the export licensing system. Such as the configuration of the five-axis linkage of high-grade CNC systems, but also for complex spatial surfaces for high-precision machining, more suitable for like automotive parts, aircraft structural parts and other modern mold processing.
Five-axis CNC programming abstract, difficult to manipulate
This is every traditional CNC programming staff are y headaches. This structure is very popular by the mold high-precision surface processing, which is the table rotary machining center is difficult to do. At the same time, the price of five-axis machines is only 30% to 50% higher than the price of three-axis machines.
A-axis and C-axis minimum indexing value is generally 0.001 degrees, so that the workpiece can be subdivided into any angle, processing of inclined surfaces, inclined holes, etc.. It can be seen that the five-axis linkage CNC machine tool system on a country's aviation, aerospace, military, scientific research, precision instruments, high-precision medical equipment and other industries, has a significant impact
Five-axis machining center price. The front of the spindle is a rotary head, can surround the Z-axis 360 degrees by itself, to become the C-axis, the rotary head also has an A-axis with can rotate around the X-axis, generally up to ± 90 degrees or more, to achieve the same function mentioned above. The advantage of this setup is that the structure of the spindle is relatively simple, the spindle rigidity is very good, and the manufacturing cost is relatively low.