【正文】 ar displacement precision, transmission part and so on gear guide screw pitches the precision, therefore the system displacement precision is low. This system structure simple, debugging service convenient, work reliable, cost low, is easy to reequip successfully. The asynchronous motor or the direct current machine drive, diffraction grating survey feedback closed loop numerical control system This system and the open system difference is: Physical location feedback signal which by position detector set and so on the diffraction grating, induction synchromesh obtains, carries on the parison as necessary with the given value, two interpolations enlargements and the transformation, the actuation implementing agency, by the speed which assigns turns towards the elimination deviation the direction movement, 江漢大學(xué)機建 學(xué)院 2020 年畢業(yè)論文 外文翻譯 第 11 頁 until assigns the position and the feedback physical location interpolation is equal to the zero. The closed loop enters for the system Enters for the system plex in the structure pared to the splitring, the cost is also high, requests strictly to the environment room temperature. The design and the debugging is all more difficult than the open system. But may obtain pared to the splitring enters for a system higher precision, quicker speed, actuation power bigger characteristic target. May act according to the product specification, decided whether uses this kind of system. The direct current servo electrical machinery drives, encoder feedback semiclosure link numerical control system Half closedloop system examination part installs in among passes in the moving parts, indirectly surveys the executive ponent the position. It only can pensate a system ring circuit interior part of part the error, therefore, its precision pared to closedloop system precision low, but its structure and the debugging all pares the closedloop system to be simple. In makes the angular displacement examination part and the speed examination part and the servo electrical machinery time a whole then does not need to consider the position detector set installs the question. The current production numerical control system pany factory quite are many, overseas famous pany like German SIEMENS Corporation, Japanese FANUC Corporation。s labor intensity, saved the labor force (a person to be possible to safeguard the multi Taiwan engine bed), reduced the work clothes, reduced the new product trial manufacturing cycle and the production cycle, might to the market demand make rapid reaction and so on. Above these superiority are the predecessor cannot imagine, is an extremely significant breakthrough. In addition, the engine bed numerical control carries out FMC (flexible manufacture unit), FMS (flexible manufacture system) as well as CIMS (puter integration manufacture system) and so on the enterprise being an information based society transformation foundation. The numerical control technology already became the manufacturing industry automation the core technology and the 江漢大學(xué)機建 學(xué)院 2020 年畢業(yè)論文 外文翻譯 第 6 頁 foundation technology. great watches the transformation the necessity From on macroscopic looked that, the industry developed country armed forces, the airplane weapon industry, in the end of the 7039。 1965 third generation small scale integration electric circuit. Computer numerical control (CNC) stage (in 1970 ~ present) In 1970, the general miniputer already appeared and the mass production. Thereupon transplants it takes the numerical control system the core part, from this time on entered the puter numerical control (CNC) the stage (which should have puter in front of the general two characters to abbreviate). In 1971, American INTEL Corporation in the world first time the puter two most cores part logic units and the controller, used the large scale integrated circuit technology integration on together the chip, called it the microprocessor (MICROPROCESSOR), also might be called the central processing element (to be called CPU). The microprocessor is applied to 1974 in the numerical control system. This is because miniputer function too strong, controlled an engine bed ability to have wealthily (therefore once uses in controlling the multi Taiwan engine bed at that time, called it group control), was inferior to used the microprocessor economy to be reasonable. Moreover then small machine reliability was not ideal. The early microprocessor speed and the function although insufficiently are also high, but may solve through the multiprocessor structure. Because the microprocessor is the generalpurpose calculator core part, therefore still was called the puter numerical control. In 1990, PC machine (personal puter, domestic custom had called microputer) the performance has developed to the very high stage, may satisfiedly take the numerical control system core part the request. The numerical control system henceforth entered based on the PC stage. In brief, the puter numerical control stage has also experienced three 江漢大學(xué)機建 學(xué)院 2020 年畢業(yè)論文 外文翻譯 第 3 頁 generations. Namely 1970 fourth generation of miniputer。 Third is renovates, for increases the precision, the efficiency and the automaticity, to the machinery, the electricity partially carries on renovates, reassembles the processing to the machine part, extensively recovers the precision。 Is advantageous for the operation and the service. When engine bed numerical control transformation should meet the above requirements as far as possible. Cannot think the numerical control installment and the ordinary engine bed connects in has met the numerical control engine bed requirements together, but also should carry on the corresponding transform