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1、<p>  畢業(yè)設計數(shù)控機床外文翻譯</p><p>  The Numerical Control Engine Bed Transforms</p><p>  Harvey B.M ackey</p><p>  First numerical control system development summary brief history and

2、 tendency </p><p>  In 1946 the first electronic accounting machine was born in the world, this indicated the humanity created has been possible to strengthen and partially to replace the mental labor the to

3、ol. It with the humanity these which in the agriculture, the industry society created only is strengthens the physical labor the tool to compare, got up the quantitive leap, entered the information society for the humani

4、ty to lay the foundation. </p><p>  After 6 years, in 1952, computer technology applied to the engine bed , the first numerical control engine bed were born in US. From this time on, the traditional engine b

5、ed has had the archery target change. Since nearly half century, the numerical control system has experienced two stages and six generation of development. </p><p>  1.1 Numerical control (NC) stage (1952 ~

6、1970) </p><p>  The early computer operating speed is low, was not big to then science computation and the data processing influence, but could not adapt the engine bed real-time control request. The people

7、can not but use numeral logic circuit "to build" to become an engine bed special purpose computer to take the numerical control system, is called the hardware connection numerical control (HARD-WIRED NC), Jian

8、Chengwei numerical control (NC). Along with the primary device development, this stage has had been</p><p>  1.2 Computer numerical control (CNC) stage (in 1970 ~ present) </p><p>  In 1970, the

9、 general minicomputer already appeared and the mass production. Thereupon transplants it takes the numerical control system the core part, from this time on entered the computer numerical control (CNC) the stage ("w

10、hich should have computer in front of the general" two characters to abbreviate). In 1971, American INTEL Corporation in the world first time the computer two most cores part -- logic units and the controller, used

11、the large scale integrated circuit technology integration </p><p>  The microprocessor is applied to 1974 in the numerical control system. This is because minicomputer function too strong, controlled an engi

12、ne 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 sm

13、all machine reliability was not ideal. The early microprocessor speed and the function although insufficiently are also high, but may solve t</p><p>  In 1990, PC machine (personal computer, domestic custom

14、had called microcomputer) 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 sta

15、ge. </p><p>  In brief, the computer numerical control stage has also experienced three generations. Namely 1970 fourth generation of -- minicomputer; 1974 five dynasties -- microprocessor and 1990 sixth gen

16、eration -- (overseas was called PC-BASED) based on PC. </p><p>  Also must point out, although overseas already renamed as the computer numerical control (namely CNC).</p><p>  Also must point o

17、ut, although overseas already renamed as the computer numerical control (namely CNC), but our country still the custom called the numerical control (NC). Therefore we daily say "numerical control", the material

18、ly already was refers to "computer numerical control". </p><p>  1.3 the numerical control future will develop tendency </p><p>  1.3.1 open style continues to, to develop based on the

19、 PC sixth generation of direction </p><p>  The software and hardware resources has which based on PC are rich and so on the characteristic, the more numerical controls serial production factory can step ont

20、o this path. Uses PC machine to take at least its front end machine, processes the man-machine contact surface, the programming, the association</p><p>  Question and so on net correspondence, undertakes the

21、 numerical control duty by the original system. PC machine has the friendly man-machine contact surface, will popularize to all numerical controls system. The long-distance communication, the long-distance diagnosis and

22、the service will be more common. </p><p>  1.3.2 approaches and the high accuracy development </p><p>  This is adapts the engine bed to be high speed and the high accuracy direction need to dev

23、elop. </p><p>  1.3.3 develops to the intellectualized direction </p><p>  Along with the artificial intelligence in the computer domain unceasing seepage and the development, the numerical cont

24、rol system intellectualized degree unceasingly will enhance. </p><p>  (1) applies the adaptive control technology </p><p>  The numerical control system can examine in the process some importan

25、t information, and the automatic control system related parameter, achieves the improvement system running status the goal. </p><p>  (2) introduces the expert system instruction processing </p><p

26、>  The skilled worker and expert's experience, the processing general rule and the special rule store in the system, take the craft parameter database as the strut, the establishment has the artificial intelligenc

27、e the expert system. </p><p>  (3) introduces the breakdown to diagnose the expert system </p><p>  (4) intellectualized numeral servo drive </p><p>  May through the automatic diag

28、nosis load, but the automatic control parameter, causes the actuation system to obtain the best movement.</p><p>  Second, engine bed numerical control transformation necessity </p><p>  2.1 mic

29、roscopic looks at the transformation the necessity </p><p>  From on microscopic looked below that, the numerical control engine bed has the prominent superiority compared to the traditional engine bed, more

30、over these superiority come from the computer might which the numerical control system contains. </p><p>  2.1.1 may process the traditional engine bed cannot process the curve, the curved surface and so on

31、the complex components.</p><p>  Because the computer has the excellent operation ability, may the instant accurately calculate each coordinate axis instant to be supposed the movement physiological load of

32、exercise, therefore may turn round the synthesis complex curve or the curved surface.</p><p>  2.1.2 may realize the processing automation, moreover is the flexible automation, thus the efficiency may enhanc

33、e 3 ~ 7 times compared to the traditional engine bed.</p><p>  Because the computer has the memory and the memory property, may the procedure which inputs remember and save, then the order which stipulated a

34、ccording to the procedure automatic carries out, thus realization automation. The numerical control engine bed so long as replaces a procedure, may realize another work piece processing automation, thus causes the single

35、 unit and the small batch of production can automate, therefore is called has realized "flexible automation". </p><p>  2.1.3 processings components precision high, size dispersion degree small, ma

36、kes the assembly to be easy, no longer needs "to make repairs".</p><p>  2.1.4 may realize the multi- working procedures centralism, reduces the components in engine bed between frequent transporti

37、ng. </p><p>  2.1.5 has auto-alarm, the automatic monitoring, automatic compensation and so on the many kinds of autonomy function, thus may realize long time nobody to safeguard the processing. </p>

38、<p>  2.1.6 advantage which derives by above five. </p><p>  For example: Reduced worker's labor intensity, saved the labor force (a person to be possible to safeguard the multi- Taiwan engine bed),

39、 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. </p><p>  Above these superiority are the pred

40、ecessor 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 (computer int

41、egration manufacture system) and so on the enterprise becoming an information based society transformation foundation. The numerical control technology already became the manufacturing industry automation the core techno

42、logy and the foundation </p><p>  2.2 great watches the transformation the necessity </p><p>  From on macroscopic looked that, the industry developed country armed forces, the airplane weapon i

43、ndustry, in the end of the 70's, at the beginning of the 80's started the large-scale application numerical control engine bed. Its essence is, uses the information technology to the traditional industry (includi

44、ng the armed forces, airplane weapon industry) carries on the technological transformations. Except that uses outside the numerical control engine bed, FMC, FMS in the manufacture process, </p><p>  Thord, t

45、he numerical control transformation content and superiorly lacks </p><p>  3.1 Transformation industry starting </p><p>  In US, Japan and Germany and so on the developed country, their engine b

46、ed transforms took the new economical growth profession, thrives abundantly, is occupying the golden age. As a result of the engine bed as well as the technical unceasing progress, the engine bed transformation is "

47、the eternal" topic. Our country's engine bed transformation industry, also enters from the old profession to by the numerical control technology primarily new profession. In US, Japan, Germany, have the broad ma

48、rk</p><p>  3.2 Numerical control transformation content </p><p>  The engine bed and the production line numerical control transformation main content has following several points: </p>

49、<p>  First is extensively recovers the function, to the engine bed, the production line has the breakdown partially to carry on the diagnosis and the restoration; </p><p>  Second is NC, the addend rev

50、eals the installment on the ordinary engine bed, or adds the numerical control system, transforms the NC engine bed, the CNC engine bed; </p><p>  Third is renovates, for increases the precision, the efficie

51、ncy and the automaticity, to the machinery, the electricity partially carries on renovates, reassembles the processing to the machine part, extensively recovers the precision; Does not satisfy the production request to i

52、t the CNC system to carry on the renewal by newest CNC; </p><p>  Fourth is the technology renews or the technical innovation, for enhances the performance or the scale, or in order to use the new craft, the

53、 new technology, carries on the big scale in the original foundation the technology to renew or the technical innovation, the great scope raises the level and the scale renewal transformation. The new electrical syste

54、m transforms after, how carries on the debugging as well as the determination reasonable approval standard, also is the technology preparat</p><p>  3.3 The numerical control transformation superiorly lacks

55、</p><p>  3.3.1 reduced investment costs, the date of delivery are short</p><p>  With purchases the new engine bed to compare, may save 60% ~ 80% expense generally, the transformation expense i

56、s low. Large-scale, the special engine bed especially is specially obvious. The common large-scale engine bed transforms, only spends the new engine bed purchase expense 1/3, the date of delivery is short. But some pecul

57、iar circumstances, like the high speed main axle, the tray automatic switching unit manufacture and the installment too requires a lot of work, costs a great deal of mo</p><p>  3.3.2 machine capability stab

58、le are reliable, the structure is limited </p><p>  Uses foundation and so on lathe bed, column all is heavy but the firm casting component, but is not that kind of welding component, after the transformatio

59、n engine bed performance high, the quality is good, may take the new equipment continues to use many years. But receives the original mechanism the limit, not suitably makes the unprecedented transformation. </p>

60、<p>  3.3.3 familiar understood the equipment, is advantageous for the operation service </p><p>  When purchases the new equipment, did not understand whether the new equipment can satisfy its processi

61、ng request. The transformation then otherwise, may precisely calculate the engine bed the processing ability; Moreover, because many years use, the operator already understood to the engine bed characteristic, uses and s

62、ervices the aspect to train the time in the operation short, effective is quick. The transformation engine bed as soon as installs, may realize the capacity load revolution. </p><p>  3.3.4 may fully use the

63、 existing condition </p><p>  May fully use the existing ground, does not need to like buys when the new equipment such to have reto construct the ground. </p><p>  3.3.5 may use the newest cont

64、rol technology </p><p>  enhances the production equipment the automated level and the efficiency, improves the equipment quality and the scale, alters to the old engine bed now the horizontal engine bed.<

65、;/p><p>  Fourth, numerical control system choice </p><p>  When the numerical control system mainly has three kind of types, the transformation, should act according to the special details to carr

66、y on the choice. </p><p>  4.1 Step-by-steps the open system which the electrical machinery drives </p><p>  This system servo drive mainly is step-by-steps the electrical machinery, the power s

67、tep-by-steps the electrical machinery, the battery solution pulse motor and so on. Entering sends out which by the numerical control system for instruction pulse, after the actuation electric circuit control and the powe

68、r enlargement, causes to step-by-step the electrical machinery rotation, through gear vice- and ball bearing guide screw vice- actuation executive component. So long as the control command pulse </p><p>  Th

69、is system structure simple, debugging service convenient, work reliable, cost low, is easy to reequip successfully. </p><p>  4.2 The asynchronous motor or the direct current machine drive, diffraction grati

70、ng survey feedback closed loop numerical control system </p><p>  This system and the open system difference is: Physical location feedback signal which by position detector set and so on the diffraction gra

71、ting, induction synchromesh obtains, carries on the comparison as necessary with the given value, two interpolations enlargements and the transformation, the actuation implementing agency, by the speed which assigns turn

72、s towards the elimination deviation the direction movement, until assigns the position and the feedback physical location interpolation is </p><p>  Enters for the system complex in the structure compared to

73、 the split-ring, 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 compared to the split-ring enters for

74、 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. </p><p>  4.3 The direct cur

75、rent servo electrical machinery drives, encoder feedback semi-closure link numerical control system </p><p>  Half closed-loop system examination part installs in among passes in the moving parts, indirectly

76、 surveys the executive component the position. It only can compensate a system ring circuit interior part of part the error, therefore, its precision compared to closed-loop system precision low, but its structure and th

77、e debugging all compares the closed-loop system to be simple. In makes the angular displacement examination part and the speed examination part and the servo electrical machinery time</p><p>  The current pr

78、oduction numerical control system company factory quite are many, overseas famous company like German SIEMENS Corporation, Japanese FANUC Corporation; Native corporation like China Mount Everest Corporation, Beijing astr

79、onautics engine bed numerical control system group company, Central China numerical control company and Shenyang upscale numerical control country engineering research center. </p><p>  When choice numerical

80、 control system mainly is each kind of precision which the engine bed must achieve after the numerical control transformation, actuates the electrical machinery the power and user's request.</p><p>  Fif

81、th in the numerical control transformation the main mechanical part reequips the discussion </p><p>  A new numerical control engine bed, must achieve in the design that, Has the high static dynamic rigidit

82、y; Movement vice- between friction coefficient small, the transmission is ceaseless; The power is big; Is advantageous for the operation and the service. When engine bed numerical control transformation should meet the a

83、bove 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 requiremen</p><p>  5.1 skids guide rail

84、</p><p>  Said to the numerical control lathe that, the guide rail besides should have the conventional lathe guidance precision and the technology capability, but also must have good bears the friction, the

85、 attrition characteristic, and the reduction but sends the dead area because of the friction drag. At the same time must have the enough rigidity, by reduces the guide rail to distort to processes the precision the influ

86、ence, must have the reasonable guide rail protection and the lubrication. </p><p><b>  5.2 gear </b></p><p>  The common engine bed gear mainly concentrates in the headstock and the

87、gear box. In order to guarantee the transmission precision, on the numerical control engine bed uses the gear precision class is all higher than the ordinary engine bed. Must be able to achieve the ceaseless transmission

88、 in the structure, thus transforms time, the engine bed main gear must satisfy the numerical control engine bed the request, by guarantees the engine bed processing precision. </p><p>  5.3 skids the guide s

89、crew and the ball bearing guide screw </p><p>  The guide screw transmission relates directly to the transmission chain precision. The guide screw selects mainly is decided requests and drives the torque req

90、uest in the job precision. Is not used by job precision request Gao Shike skids the guide screw, but should inspect the original guide screw attrition situation, like the pitch error and the pitch accumulative error as

91、well as matches the nut gap. The ordinary circumstances skid the guide screw to be supposed not to be lower than 6 levels</p><p>  The ball bearing guide screw rubs loses slightly, the efficiency is high, it

92、s transmission efficiency may above 90%; Precision high, the life is long; When start moment of force and movement the moment of force approaches, may reduce the electrical machinery to start the moment of force. Therefo

93、re may satisfiedly compare the high accuracy components processing request.</p><p>  5.4 safe protection </p><p>  The effect must take the security as a premise. Transforms in the engine bed mu

94、st take the corresponding measure according to the actual situation, cuts noticeable. The ball bearing guide screw vice- is the precision part, when the work must take strict precautions against the dust is specially the

95、 scrap and the hard sand grains enters the roller conveyer. On longitudinal guide screw also coca overall sheet iron safety mask. The big carriage with skids two end surfaces which the guide rail conta</p><p&g

96、t;  Sixth, After the engine bed electrical system transformation, to operates, the programmers inevitably brings the new request. Therefore ahead of time carries on new system knowledge training to the operator and the p

97、rogrammers to be extremely important, after otherwise will affect the transformation the engine bed rapid investment production. The training content should include the new operation kneading board disposition, the funct

98、ion, the instruction meaning generally; New system functional sc</p><p>  the numerical control transforms se Transforms the scope according to each equipment differently, must beforehand design the connecti

99、on partial transformations, if transforms completely, should design the electro-mechanical transformation connection, the operation kneading board control and the disposition, the interconnection partial contacts, the pa

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