Communicate the servo application in numerical control

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20 centuries since machine tool of 50 time occurrence numerical control, regard numerical control machine tool as the servo of main component, wait for the development of relevant technology theoretically as electric power of new material, electron, control, experienced arrive again to dc servo into servo from the pace the today's process that communicates servo. Communicate the day of servo technology to be exhibited inereasingly, communication servo will replace dc servo in the round stage by stage. Numerical control (NumericalControl) the abbreviation that is numerical control technology. It is to use the information of digitlization to have pilot to process of machine tool and treatment a kind of method. Numerical control system is the substantial of numerical control machine tool, it develops as the development of computer technology. Present numerical control system is complete the work that place of hardware numerical control does before by the computer, to emphasize particularly, also call computer number to control a system sometimes. Computer number controls CNC (ComputerNumericalControl) the system is with microprocessor the technology is a feature, measure technical progress as electronic technology, computer technology, numerical control technology, communication technology and nicety and develop a perfect kind of advanced treatment to make a system ceaselessly. CNC system block diagram sees the graph is shown 1 times, it equips by face plate of equipment of output of numerical control program, input, operation, CNC, can make up Cheng controller (PLC) , main shaft servo, feed servo, detect equipment and the composition such as a few electric and auxiliary unit. Servo is with actuating device, electric machinery is control object, it is core with controller, it is actuator with device of power transformation of electric power electron, the system of electric drive automation that forms below the guidance of automata theory, it includes servo driver and servo electric machinery. The action of servo of numerical control machine tool depends on accepting the command signal that comes from numerical control device, part of shift of drive machine tool follows instruction pulse moves, what assure a movement is fast and accurate, this is about to beg the speed of high quality and positional servo. The technical index such as the precision of numerical control machine tool and speed basically often depends on servo. Should the servo development of numerical control machine tool and the servo that classify numerical control machine tool satisfy: of the following and main demand? Mow of provide for of Huan of arm of  of Tao of  of  sparrow Ling assist bone of Zhuang of  of brother's son of Meng of  of eggplant of material of  Chen  blows Kun  canister to hook ジ children's hair to treat Peng lofty of Mie of  of  of Song of farsighted  Ge knocks at mu of ㄎ tan1huan4  group  of tan1huan4 of ㄎ of Tuo thoroughfaring cook a meal takes M. It asks servo follows command signal follows not only the error is small, and answer should fast, stability is close friends. After the system gives an input, new balance can be achieved after brief adjustment or be to be disturbed action to issue can rapid extensive to recover from an illness by the outside the balance position that come. Timing scope asks to differ as a result of workpiece material, cutting tool and treatment greatly, want to make sure for love or money of numerical control machine tool can obtain first-rate cutting condition, servo must have enough timing range, can satisfy high speed to machine a requirement already, can satisfy requirement of low speed feed again. Timing scope is more than 1:1 commonly0000. And when low speed cutting, still ask the torsion that has bigger stability is outputted. Nextpage system dependability is close friends the utilization rate demand of numerical control machine tool is very high, often 24 hours of successive jobs cannot stop machine, ask the job is reliable consequently. The basic composition of servo of numerical control machine tool is shown 2 times like the graph. The servo of numerical control machine tool is pressed have control system and closed-loop control system for open loop without cent of feedback detecting element. Drive control unit is the signal that executes feed instruction translate into component place need, executive component turns this signal for mechanical displacement. System of open loop control is mixed without feedback detecting element control segment quite, these are closed-loop control systems must part. Graph the basic composition servo of 2 servo is feed drive system and system of main shaft drive by utility and functional cent. By have control system and closed-loop control system for open loop without cent of feedback detecting element. Those who press executive component is different, cent enters servo, dc servo and communication servo for the pace. The pace is in into servo 20 centuries before 60 time, the pace enters servo is the hydraulic pressure servo that takes electric machinery drive with the pace electromotor or it is into electric machinery with power pace direct drive is a feature, servo uses open loop control. The pace accepts pulse signal into servo, its rotate speed and the angle that had turned depend on the frequency of instruction pulse or several. Because do not have,feedback link, the pace depends on into the precision of electric machinery the precision of step pitch horn, positive drive clearance, its precision is so inferior. And the pace appears easily when low frequency into electric machinery oscillatory phenomenon, its output moment of force lifts along with rotate speed and drop. It is open loop control into servo as a result of the pace again, the pace is starting frequency into electric machinery when exorbitant or load is too big easy appear " lose a condition " or " locked-rotor " phenomenon, the rotate speed when stopping is exorbitant and easy the phenomenon that has appeared to rush. The time that additionally the pace stops to need to working rotate speed quickly into electric machinery Cong Jing is longer also, speed is answered slower. But because its structure is simple, adjust easily, the job is reliable, the characteristic with inferior value, in a lot of requirements not tall circumstance still can apply. Shed servo continuously after 70 time of 60 ～ , numerical control system uses dc servo mostly. Dc servo electric machinery has good wide timing performance. Output torsion is big, overload capability is strong, servo also controls development to be closed-loop control by open loop, obtained in industry and relevant domain consequently more extensive apply. But, as the rapid development of modern industry, its are corresponding if equipment is accurate servo offers pair of report such as robot of numerical control machine tool, industry higher and higher demand, especially the function such as precision, dependability. And what traditional dc motive uses is mechanical commutator, a lot of problems are faced in using a process, if brush and commutator are easy,wear away, safeguard workload big, cost can produce scintilla when inverting of tall; commutator, make the top rotate speed of electric machinery and applied environment are restricted structure of; dc electric machinery complex, cost generates interference high, easily to other equipment. The existence of these problems, restricted dc servo to be in the application of circumstance of drive of servo of high accuracy, high-powered requirement. Communication servo is aimed at the defect of dc motive, people seeks the means of the dc servo electromotor that has mechanical commutator and brush with communicating servo electromotor to replace in effort all the time, in order to satisfy all sorts of application domains, especially the need of domain of drive of high accuracy, high-powered servo. But because communicate electric machinery to have strong coupling, nonlinear character, control is very complex, so high-powered apply get all the time confine. Since 80 time, wait for the development of each technology as electronic electric power, especially the development with contemporary academic control, the breakthrough of algorithmic respect is controlled in vector, the problem that puzzling AC motor all the time so is able to solve, land of communication servo development is faster and faster. The characteristic communication servo that communicates servo besides have stability good, fast sex outside the characteristic with good, tall precision, does with system of dc servo electric machinery photograph comparing have a series of advantage: ? Melt  of analyse of Li of channel of instrument Miao of  of  of Beng of Li of closely question of Bi of the Huaihe River of arm of exhausted  of bend so as to breakstubborn of Bin of Liang of Nai of storehouse of Bian of Zha of Huang of joke of Bi of the Huaihe River of Jian black  enlighten cap of frequency of bail of fall from the sky of tip of bottle of bend so as to breakstubborn of Bin of wetting  of exhausted  of bend so as to breakstubborn identifies fact of sneer  β to be troubled by stretch tight Jian000, the gearshift of electric machinery compares high-powered servo to already amounted to 1:10000 above. Wide, static difference leads scope of timing of drive of machine tool of contented numerical control to ask smally. Quadrature frequency character is good, alternating current machine is constant moment of force to output, namely in its less than of rated rotate speed outputs rated torsion, constant power output is in above of rated rotate speed. And have torsion overload capacity, can overcome the inertial moment of force that inertial load is starting the instant. Torsion of output of servo of contented machine tool is dynamic and big, corresponding the demand with high precision of good, fixed position. The communication servo that the servo of communication of research current situation of servo of Nextpage home communication includes to be based on asynchronous electromotor and the communication servo that are based on synchronous electromotor. What at present the machine tool basically uses is servo of communication of permanent magnetism synchronism. The field researchs in communication servo, the research of Japan, United States and Europe walks along alive bound front row all the time. An Chuan company of Japan in 20 centuries 80 time metaphase develops drive of servo of the first communication. Subsequently FANUC, 3 water chestnut, soft coarse company rolls out respective communication servo early or late, these products of abroad are based on asynchronous electromotor mostly. Home compares evening in the research that is based on asynchronous electric machinery to communicate servo, still come out without the product so far. A lot of scholars of domestic put the emphasis of research on servo of electric machinery of permanent magnetism synchronism. The unit such as the factory begins electromotor of institute of automation of Shenyang of institute of institute of machine tool of the university of Hua Zhongke ability of our country, Beijing, Xi'an small electromotor, Chinese Academy of Sciences, Lanzhou to consider and roll out communication servo. Among them, the industry of drive of servo of high accuracy numerical control that the type of word of DA98 total number that produces by company of Guangzhou numerical control communicates servo actuating device to be in our country has opened a phase, broke the pattern of foreign company monopoly, started ethical brand epochal. The signal that communicates servo and interface of numerical control system have 3 kinds of pattern, also be 3 level that it experiences. With home for, the DA98 of Guangzhou numerical control belongs to generation also is driver of epoch-making a kind of servo, it is home type of word of the first total number communicates servo actuating device, it accepts direction to command pulse. The 2nd generation is the EDB series that is a representing with Aisidu, it can accept pulse to command signal not only, still can accept speed to control or be the input that torsion pilot imitate measures. The 3rd generation is network communication servo. Network servo is technology of industrial spot bus line and the organic union that digitlize communication servo completely, technology of servo of complete digitlization communication can make the user adjusts parameter according to laden state, also leave out the not stable element such as the drift that place of loop of a few imitate produces. Use the network that is based on spot bus line to control a technology, enter microprocessor and place of interface of spot bus line driver of servo of electric machinery of total number word communication, the servo of total number word that forms intelligence independence controls unit, its direct link arrives on industrial spot bus line, formed the new-style network that is based on spot bus line to control a system. Reduced hardware amount and even the line, each intelligence paddles his own canoe on unit structure, but with the outside and mutual implementation data is shared, and can add hang other spot to control device, expand easily. So far network communication servo implement still do not have mature product in home. The network communication servo that development of institute of robot of Beijing aerospace university designed a kind to be based on DSP ＋ FPGA+ASIPM controls a system, principle prototype already got abecedarian test and verify on three-dimensional engraving tool. Current servo implement driver interior uses processor of high speed DSP mostly, advanced all sorts of advanced motion to control the algorithm use on new-style driver. On hardware structure each big servo supplier uses DSP+CPLD mostly (FPGA) structure, as a result of DSP and CPLD (FPGA) can repeat process designing sex, what can realize communication servo is modular can reframe. The software that wants to differ accordingly for systematic configuration only (include to control algorithm) can be controlled and electric machinery of servo of synchronism of drive asynchronous electric machinery, permanent magnetism, without brush dc machine, and the new configuration that passes pair of FPGA is OK still drive dc electric machinery and pace of high pressure of three-phase induction type enter electric machinery. This upgrades with respect to what be numerical control machine tool and the innovation left a lot of spaces. The development trend that communicates servo the ceaseless development as productivity, communication servo is sided with compositive change, intelligence is changed and the way of network develops. Compositive change use onefold, muti_function control unit, the setting that passes software realizes positional control and speed to control a function. The feedback unit that can use itself to configure makes half closed circuit or be the system of full closed-loop control that makes high accuracy through exterior interface. Intelligence changes servo implement the intelligence that controls mode is changed, like interiorly beforehand process designing achieves orbit of some kind of motion, dominate the IO opening of this site periphery, principal and subordinate is taken to follow inside mode is adjusted, electronic cam. Network servo implement implementation network is distributed control. Servo implement implementation is modular can reframe, save cost. The last word shows machine tool of acting numerical control is forward nicety is changed and high speed changes direction to develop. Regard numerical control machine tool as the servo of main component, more and more choices stay in communication above servo, it is had other the dominant position with a few kinds of unparalleled servo. As the development that exchanges servo technology, communication servo will replace dc servo gradually in the round. CNC Milling CNC Machining