As an advanced processing method, Cnc Machining technology has been widely used in the manufacturing industry. Its unique high-speed, high-efficiency, high-precision and rich processing forms and many other good usability have been more and more popular. The recognition of the new telecommunications system has led to new structural forms, the production of modern radars requires new technological methods, and the application of CNC machining technology is particularly prominent.
2 Advantages of CNC machining technology Compared with ordinary machining technology, CNC machining technology has great advantages, and with the technological advancement of CNC machining technology and related disciplines, the superiority has become more prominent. From the point of view of motion control, CNC machining has made a qualitative leap in the following two aspects: (1) Trajectory control, CNC machining technology * The outstanding feature is that it can drive multi-axis linkage through digital control to form a designated tool path and realize ordinary machining. It is impossible to realize or even if it can be realized, it is more complicated and cumbersome profile processing. In addition, for the processing of different parts, the trajectory control only needs to modify the program software, without changing the tooling equipment or the production line, and the adaptability is greatly enhanced; (2) Positioning control, the unique closed-loop compensation function and programmability of cnc machine tools (ie Micro feed can be realized), which determines that the CNC machine tool can obtain accurate positioning, effectively reducing random errors and improving machining accuracy. From the point of view of process parameter control, CNC machining can obtain a wide range of stable process parameters. Digital control can accurately determine the tool feed and spindle speed, thereby improving the processing quality. The high speed of CNC machine tools provides the material basis for the future trend of high-speed machining. All these features make CNC machining technology with high precision, high efficiency, high flexibility and wide range of processing characteristics. 3 CNC machining technology in the feeder system Application and development trend 3.1 Application of CNC machining technology in feeder systems Feeder systems in the electronics industry have developed so far, and there have been a wealth of materials and structures. The advancement of CNC machining technology makes these new designs possible. The five aspects are closely related to CNC machining technology. 3.1.1 Power divider, sum-differencer, modern power divider, and sum-differencer design mostly adopt the design idea of system integration, especially airborne radar, power divider, The sum and difference devices all adopt a networked structure, which unifies the multiple single-function components used before into one device, reduces loss, reduces noise, and is conducive to the acquisition of accurate telecommunication parameters. Like a power divider in our XXX product, The structure diagram is as shown.
The shape and position accuracy requirements are relatively high (caliber 20. 05<5±0.05), and the wall is thin (1mm), easy to deform, complicated in structure, and difficult to process, which cannot be processed by ordinary milling machines. In the process design, we use the MH1000 series Cnc Milling Machine to carry out the cavity milling force, and the process parameters adopt the settings of high speed, small depth of cut, and micro feed. At the bottom of the blank, a craft rib of 0.05 is left, which reduces the positional distortion. Numerical control processing has played an irreplaceable important role in the process of forming process parameters of curve trajectory, controlling process rib processing and so on.
3.1.2 Feeder horns With the development of radar index parameters towards a wider range and more accurate data measurement tactical requirements, the structural design of the feeder horns has also become larger and more precise, which brings higher requirements for production and processing. , Among them, the requirements for numerical control technology are becoming more and more urgent for program control. The characteristics of the CNC wire cutting machine tool are fete (blish electroformed aluminum core Ji composition as shown in Figure rf3.
For example, a feed horn in our XXX product, the caliber was changed three times from ±0.15, and the cavity contains 78 pieces of coupled copper plates (thickness 1mm) on both sides of the cavity. The structure diagram of the electroformed aluminum core is shown in the figure. Among them, 1mm narrow slot * depth 42. 39001, the current milling method can not be processed, can only use the electric discharge wire cutting machine to process 78 narrow slots on both sides, and to accurately ensure the slot spacing and width, you can only use CNC wire cutting In fact, due to the inherent advantages of CNC wire-cutting machine tools, most of the current wire-cutting machine tools use numbers and do not need to manufacture specific-shaped electrodes, only need to enter the control program, and the fit gap of the matching parts can be easily adjusted through calculation; (2) The use of digital control of multi-axis compound motion can process complex-shaped straight-grained surfaces such as planes and cones; (3) The electrode wire is constantly updated or used reciprocatingly during processing, and the impact of electrode wire loss on accuracy can be ignored; (4) High degree of automation, convenient operation, short cycle and high efficiency.
3.1.3 Circle moment transformation The circle moment transformation is another typical functional part in the feeder system, which realizes the smooth transition of electromagnetic waves from a round diameter to a square diameter. Such parts generally use electroforming technology. The traditional route of cast aluminum core processing is generally preparation-turning-milling-clamp-grinding, in which the milling bevel must be accurately connected to the turning surface, which requires high personal technical requirements for the miller. After the CNC lathe with a milling power head is used for processing, all the processing of the square and the circle can be completed in one clamping, and the process route becomes preparation-turning-grinding, which not only reduces the number of procedures, improves efficiency, and reduces the personal impact on workers. The technical requirements are convenient for the realization of socialized production.
3.1.4 Phase shifter, duplexer aluminum-based composite material) Modern radar gradually uses a new type of microwave material-an aluminum-based PTFE copper clad laminate. It is a multi-layer composite material composed of three layers of materials (copper foil layer, dielectric The thickness of the copper foil is generally a few microns to a dozen microns. The thickness of the dielectric layer is generally a few millimeters to a few millimeters, which directly affects the dielectric constant. The material of the dielectric layer is mainly polytetrafluoroethylene (PTFE), which is mixed with a certain amount of ceramic powder. The thickness of the aluminum alloy plate depends on the needs of the component structure. Radar products using this material generally have the following requirements for machining: the edge of the copper foil must not be flanged, especially the hole on the line must be flat and not disconnected from the edge of the line; the surface of the workpiece must not have scratches and pits.
RT/Duroid6010 aluminum-based PTFE copper clad laminate was selected for the duplexer in a certain product of our institute. In view of the high-precision size requirements of this new material and the complex structure of the duplexer, we conducted process analysis from the following three points.
The processing effect diagram of the duplexer has not changed, and the drilling has been improved. According to the actual data of our institute, the zero point of each part must be carried out according to the actual data. From the composition and requirements of the material, we cannot use the usual processing aluminum The speed required for alloy should be the machine tool material with higher spindle speed. The recommended speed of Y3 milling cutter in the machining manual is /min. This speed is high-speed cutting. Ordinary machine tools cannot meet the requirements. Only CNC machine tools with new motors can be considered. In the test, when other cutting parameters are the same, start from the speed/min and gradually increase the speed. It is found that the Y 4 milling cutter is at a speed of 6000r/min, and the Y3 milling cutter and Y1.65 drill bit is at a speed of 8000r/min. Basically there is no flanging, and the burrs are also very small. It can basically meet the processing requirements and change the tools with smaller diameters (keyway milling cutter Y2Y 1, drill bit Y1Y0.7YQ6–These tools are necessary for processing duplexers), and the speed is still It is 8000r/min. We decided to perform milling processing on a machining center with a rotation speed of 10000r/min. The picture shown is the front milling step, cavity and upper and lower sides of the duplexer, the front milling step, the narrow groove and the left side. , On the right, the drawing of a part with a relatively complex structure requires the accuracy of the position between the machining profile and the line to be ±0.05. We use the pin hole 3-Y30002 for positioning, and the pin size Y is mainly 0 0i to ensure the above accuracy. Obviously, this requires that the line production accuracy is less than ±0.05. Considering the processing pin hole error, positioning, clamping error and actual processing error, the line production accuracy should be controlled at ±0.02. But currently our line production accuracy is +-003. Therefore, rely solely on Pin positioning cannot guarantee the accuracy requirements of ±Q05. It must be corrected. The measuring range of our existing three-coordinate measuring instrument is 200<100, and the whole board cannot be measured at a time. In order to ensure the accuracy and batch production efficiency at the same time, we have equipped the machine tool with an optical measuring instrument to directly measure on the machine tool by the inspector to provide the processor with actual measurement data. The advantage of this operation is that the measurement environment is basically the same as the processing environment, which ensures that the precision duplexer requires frequent tool replacement. It is also a mass production. In order to shorten the cycle and improve efficiency, a machining center should be selected. The machining center we chose is the HAAS20HP produced by the Swiss “Mikron” company. It has 20 tool positions (15 tools required for machining), repeat positioning accuracy Q002, drilling accuracy ±Q02 (meeting ±0.05 accuracy requirements), and stroke 500<1.5 Tooling and Die for Feeder Manufacturing Feeder manufacturing requires many tooling molds, such as: (1) positioning fixtures for machining (milling, wire cutting, etc.); (2) welding fixtures; (3) deformations such as cold drawing and hot extrusion Core molds; (4) Casting molds for precision casting; (5) Bending molds, etc. The manufacturing and processing of these tooling molds themselves also require the application of CNC machining technology (such as CNC wire cutting technology, etc.) 3.2 Application of CNC machining technology in feeder production As the terminal of modern manufacturing, CNC machining technology will inevitably develop simultaneously in both software and hardware with the development of modern manufacturing, and this development will also continue to meet the needs of modern radar feeder production. High-speed hardware must be vigorously promoted. The main advantages of high-speed machining are: (1) High efficiency, which can remove a large amount of excess material in a single process, but also achieve high machining accuracy and surface quality, and greatly reduce the processing time of parts; (2) For processing difficult-to-cut materials, nickel-based alloys, titanium alloys, fiber-strength plastics, etc. become easy to cut under high-speed cutting; (3) Dry cutting can be achieved. According to statistics, in developed countries, coolant and waste liquid treatment account for the total production cost 14% to 16%, and cutting tools account for ~ 4% of the total production cost. Dry cutting can greatly reduce production costs. At present, many research institutions in the industry are studying the implementation details of dry cutting. High-speed cutting can play an important role in achieving dry cutting. The CNC machine tool with the new motor can fully meet the needs of high speed, high power, high feed rate and high acceleration required for high-speed machining. I believe that CNC machining technology will play an important role in the future high-speed machining software. On the basis of consolidating and developing CNC technology and intelligent manufacturing technologies such as processing units and flexible manufacturing units, we will comprehensively use concurrent engineering technology and integrated technology. , Intelligent technology, network technology and other advanced technologies to realize efficient and flexible manufacturing system, and establish a flexible, streamlined and flexible manufacturing model ) And virtual manufacturing (VM) are developing very rapidly. As the execution terminal of these advanced technologies, CNC machining technology will have a broader development space. The technological progress of CNC machining will definitely make greater progress in the development of the modern radar industry. contribute
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