Supersonic cut system and stability study composite material

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Colophony radical composite material with its superior performance, can bear the weight of as structural material already bear, can produce effect as functional material again, the application that waits for a domain in aerospace and dimensional technique is wider and wider. Composite material component is producing colophony radical in the process, basically use legal system of fiber lay up to build, because the cut of this fiber fabric issues makings general,affect the quality of the product and manufacturing efficiency directly. The cut of fiber fabric basically has cut of cut of mechanical cutting tool, jet of Laser Cutting, water and ultrasonic cut. Among them, the application of supersonic cut technology already had time of nearly 20 years up to now, the research and development of each big airlines manufactory of Europe and United States and aviation composite material produces an enterprise to already used supersonic cut equipment to apply at production widely. Be in however home, this one technology still is in phase of initial stage application. Photograph of cut of the cut of mechanical cutting tool with the tradition, jet of Laser Cutting, water is compared, the ultrasonic cut method of fiber material has a few more the following advantage: (1) won't produce phenomenon of vulcanization of blade the crucial point in that way like CO2Laser Cutting composite material; (2) have very favorable craft effect; (3) cut process free from contamination, it is the cut that do not have dirt almost; (4) can the material with cut careful grain, because cut deepness is controlled accurately, can make sure spacer film is not destroyed when cut material so. Be based on above advantage, make ultrasonic cut technology is in develop a school of one's own of domain of composite material cut, accept favour fully. Supersonic cut system is different from traditional processing technique, the fundamental of supersonic cut technology is to use an electron the ultrasonic that supersonic generator produces certain limits frequency, pass park next inside supersonic cut head supersonic - mechanical converter, will originally the mechanism that the supersonic vibration with amplitude and very little energy changes Cheng Tongpin to lead is oscillatory, repass resonance magnifies, get enough big, the amplitude that workpiece of OK and contented cut asks and energy (power) , conduct this part energy the cutting tool that carries to supersonic cut the top of head finally aspirant travel beforehand the cut treatment that dip takes. According to shop belt craft is reached beforehand dip makings is supersonic the effective demand of cut, combine domestic and international ultrasonic to apply newest research positive result, the supersonic cut system that designs development by oneself basically includes system of vibration of supersonic cut generator, supersonic cut and supersonic cut machine 3 component, the plan of supersonic cut unit that if the graph is shown 1 times,devises. Among them, of supersonic amplitude offer finish by supersonic generator and supersonic cutting tool with control; The transverse movement that mechanical platform basically controls supersonic cutting tool, roll that circles oneself and through pneumatic control system provides cut pressure. Generator of 1 supersonic cut is supersonic cut generator namely ultrasonic power source, its action is the electric oscillation signal of the ultrasonic frequency of alternating current translate into 220V or 380V. Usually, the result when ultrasonic device is used alone is right, because when the design integral impedance is secured,basically be, power matchs easily. And when be being used actually, device installation is on integral equipment, suffer the effect of a lot of element such as laden, interference and temperature, often cause the systematic parameter such as syntonic frequency, equivalent impedance to produce drift change, make the frequency of the frequency of supersonic generator and transducer does not match, bring about output power loss is bigger, the amplitude of transducer drops, cannot assure cut quality and efficiency. The supersonic generator in this system has frequency to dog automatically function, through soft hardware implementation frequency dogs automatically, make impedance and frequency change according to the spot at any time, achieve real time to match, make supersonic and oscillatory system is in optimal job status thereby, changeover efficiency is the biggest. System of vibration of 2 supersonic cut is supersonic cut vibration system is main by razor blade of lever of supersonic transducer, supersonic luffing, cut. Among them, the action of supersonic transducer is changeover of will telegraphic date the signal that it is sound; Luffing lever is one of supersonic treatment facilities main component. It basically has two effect: (1) get together can action -- be about to mechanical and oscillatory displacement or speed amplitude enlarge, perhaps concentrate energy on lesser radiation face to undertake getting together can; (2) deliver sound energy effectively load -- the transformer that serves as mechanical impedance, undertake between transducer harmony load impedance matchs, make supersonic energy is transmitted effectively to load by transducer. The assorted form of the supersonic luffing rod that this system uses and cut razor blade, if the graph is shown 2 times, to obtain bigger amplitude enlarge multiple (Am) , use rod of luffing of form of a flight of stairs; For improvement or the stress concentration that abate and sectional mutation is in, circular arc is used to transfer in sectional and choppy place means. (1) the influence of dimension of cut razor blade. Differ through commutation the cut razor blade of length and width (ply is changeless) undertake matching with transducer, in finite yuan reach below the analysis the addition as bit length, the rule that integral natural frequency drops, and descendent rule shows linear change basically; And when bit width greatens, integral natural frequency also drops, and downtrend is a few bigger. Additional, as the addition of bit length, supersonic luffing lever and the enlarge multiple after cut razor blade is combined (Am) shows ascendant trend; As bit width reduce, enlarge multiple rises somewhat. Because this can choose appropriate length and width attune,rectify integral natural frequency and amplitude enlarge coefficient. (2) the influence of material of cut razor blade. The change of material of cut razor blade produces certain effect to the acoustics parameter of assembly necessarily. The influence for research data property and do not break practical, chosen bit material is hard alloy and aluminium respectively. Through finite yuan the method analysed bit data the influence of supersonic to whole property, by imitate the result can be reached, choice duralumin expects for material of cut razor blade the natural frequency impact to assembly is very little; When material is hard alloy, natural frequency span is very big. From amplitude enlarge multiple finite yuan in light of analytic result, the change of material property is affected to amplitude enlarge multiple not quite. The affiliation of cut razor blade makes integral natural frequency drops, for with supersonic brace up child frequency matchs, the natural frequency that increases supersonic luffing staff can be reduced and even offset the frequency that joins cut razor blade to cause drops. Through the experiment the analysis gives result and simulative result to be close to very. Machine of cut of ultrasonic of machine of 3 supersonic cut includes drive system, pneumatic to control option and mechanical platform, of pressure of the main cut that finish bring to bear on, of the control of speed of the exact location of cut deepness, cut and cut workpiece fixed wait for a few functions. Speed of cut of the limit in supersonic cut experiment is a very main index, be a paragraph of divide evenly is obtained in finite journey fast cut journey, must raise character of trends of machine speed pilot. The system uses a pace to regard drive as the component into electric machinery, slideway of guide screw of THK accurate ball deputy for transmission implement, cut speed can amount to 10m/min. To satisfy craft requirement, cut device installation is the first in the shop of machine tool of type of door of 5 axes dragon on (graph 3) , among them the main demand that 5 axes linkage brings with satisfying curved surface to spread, and cut system by cut transverse feed axis, cutting tool rotates axis and composition of axis of feed of cutting tool axial. Cut system can be followed according to cut mode use platform of fixed position of Yu Long door. System of numerical control of Nextpage this machine tool is accused by labour machine (IPC) , but process designing much axle control implement (Programmable Multi-Axis Controller, PMAC) , switch quantity control plate gets stuck (PCL-725, PCL-730) , actuating device of I/O interface, servo and composition of power source actuating device. Regard numerical control as systematic core, labour accuses machine is responsible and whole the information processing that controls a system and tiring-room operation, issue a machine to issue an order to each, harmonious carry momentum and the combination that switch movement measures are operated. Athletic controller is received go up the control instruction of a machine, with this control motion of each axis electric machinery realizes CNC Machining. The PMAC that this system uses company of American DELTA TAU to be developed technically controls unit as motion, the processor of DSP56001/56002 number signal that the CPU that it uses is Motorola company (40MHz) , can control synchronism of 8 movement rod to achieve linkage at the same time. Besides can implement moving program, still can program of monitoring PLC tiring-room, both because sequential is different not mutual conflict. Before executive exercise program, PMAC must dictate to motility and be not motility instruction to undertake be computationaled beforehand, coordinate the virtual campaign of actuator thereby. Supersonic cut experiment lets off Cheng in the shop in, carbon fiber beforehand dip belt and agglutinate of mount of a back are together, back mount has oriented effect. The requirement in cut process can be cut off only beforehand dip belt, cannot cut off the back mount of oriented action, and the carbon fiber in this experiment beforehand the thickness that dip takes is 0.

12mm, the ply that carries mount on the back also has 0 only.

1mm, this is brought about control cut deepness very hard from beginning to end with traditional method in 0.

1mm left and right sides, cannot come true already will beforehand dip belt is cut off and do not hurt the slip sheet that reach a back. This system uses ultrasonic to output the amplitude of end and accurate axis to have fixed position in luffing lever, make amplitude and cut deepness control are in the limits of the requirement, make sure back mount is not cut off. In the meantime, because frequent vibration makes the temperature of cut knife head rapid,rise in cut process, affect cut quality then, can let supersonic generator call the police even suspend output. For this, wind cold device is joined to cool on cut head cut knife head. To solve automatic shop to take a course apoplectic cold time is opposite the influence that system of special and supersonic cut stabilizes function, design physics to emulate experiment platform by oneself, automatic shop takes imitate machine is supersonic the working status of cut, if pursue,4 are shown. This are simple and easy platform has transverse and mobile axis 1, runner shaft coming back 1, transverse and mobile axis realizes the feed of cut movement way, runner shaft coming back is for imitate the shop is the first the cut effect below is spent in different corner coming back. On this physics platform, we designed 3 experiments to study stage by stage. Above all, maintain supersonic cutting tool successive intermittence moves, its process is as follows: Supersonic cutting tool drops, supersonic cutting tool is started, fast cut comes beforehand dip takes another side, cutting tool is raised after, shut supersonic cutting tool; Drop again immediately cutting tool, make supersonic cutting tool is started, return quickly to original a side, shut cutting tool, raise. Cut course is included twice in this process, cut of such move back and forth 10 hind stop. Wait for wind of classics of temperature of cut knife head cold 45 ° , 90 ° rotate to part again after falling cut. If successive cut frequency and cooling time express 1 to show. Below cut of different point of view, adopt accurate axis fixed position, make cutting tool amplitude and cut deepness control are in the limits of the requirement, control then beforehand the cut deepness that dip brings two end agrees and guarantee against cuts off back mount. In sheet second in successive cut process, be opposite to solve cutting tool temperature to rise the influence of supersonic cut system, the frequency that works to supersonic power source and power change undertook experimenting analytic, if metabolic trend pursues 5 with the graph 6 are shown. By can see in the graph, in successive cut frequency not much circumstance falls, power source frequency and power source power show drab change along with the addition of cut frequency; Although odd the frequency has successive cut 10 times only, but the cut knife head that measures after cut is average temperature already rose to 57.

5 ℃ . This shows, power source frequency rises along with the temperature of cut knife head drab drop, and power source power rises along with the temperature of cut knife head drab rise, and this temperature is returned in power source the job accepts limits inside, won't cause power source to call the police output. Next, on the foundation that experiments in front, be in artificially wind is installed between cut every time cold time-interval 10s, if trial record expresses 2 to show. Nextpage takes the experimental data observation when cut of 0 ° , every time the change of power source frequency after cut is shown 7 times like the graph. By the graph in knowable, in introduce after artificial and removed wind is cold, power source frequency increases to be reduced gradually along with cut frequency to constant frequency; In initiative phase, power source frequency rises to be reduced quickly along with cutting tool temperature, increase to when the frequency 40 hind, because the balance of knife head temperature makes grading of power source frequency sexual ground is slow reduce, till constant in 39.

71kHz. Because be in every time cut process beginning and end added 10s wind cold time to cut knife head, in cut 100 hind the temperature of cut knife head rises to 58.

9 ℃ , satisfy the regular job of power source, without call the police output. Finally, the kind that carries programme controll sets wind cold time, undertake cut experiments automatically. If trial record expresses 3 to show. In this groups of experiments, we pass what M code realizes cutting tool to raise with drop, use circular statement to implement automatic cut 200 times, partial program code is as follows: ... P55=0 M22 Dwell 500 F1000 While (p55<200) ; Cut frequency G91 G01 W - 1270... Dwell 8000; Time interval 8 seconds M22 Dwell 500 P55=P55+1... in experimenting here, change of power source frequency and in front the test is same, be reduced as the addition of cut frequency and tend gradually constant 39.

64kHz, advanced in 5 groups of experiments, picture of power source indication power appeared unusual, but power worth is invariant in moving process; After waiting for supersonic power source to restart, the job shows all normal, increasing as cut frequency it is thus clear that, below the circumstance that temperature of cut knife head rises, the stability of supersonic cut system still remains to check test and verify further. Combine this physics platform and plane of band of shop of dragon door type, choose appropriate craft parameter to undertake cut shop takes a test, the graph shows the cylinder that to be in condition of cut of 0 ° , 45 ° plays 8 times to spread put effect figure, beforehand dip takes cut smooth level off does not have burr, explain this supersonic cut system has certain actual project to use value, provided certain guidance for the following thorough research. Big airlines of last word our country is versed in Cheng has been started, the dosage of composite material will be increasing, final upper limit will be adjacent have Boeing more than even the composite material dosage of 787 level. And automatic shop belt sets composite material to become one of technical bottleneck that achieve this one goal likely fully, the country already included numerical control to weigh big special focal point to manufacture equipment this facility. Supersonic cut technology serves as one of crucial technologies in this equipment to be taken seriously increasingly also, domestic aviation industry already began to use this technology at production, after passing supersonic cut beforehand dip takes quality exceedingly good, have without burr, wear away without cutting tool, force of side direction cut speed of small, treatment precision of fast, treatment is advanced a series of advantages, but its stability still remains at further research. Believe those who adopt this technique to drive, the aviation composite material of our country makes a technology be sure to one rises newly. CNC Milling CNC Machining