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1、<p>  The Numerical Control Engine Bed Transforms</p><p>  Harvey B.M ackey</p><p>  First numerical control system development summary brief history and tendency </p><p>  In

2、 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 tool. It with the humanity these whic

3、h 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 humanity to lay the foundation. </p>

4、;<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 bed has had the archery target chang

5、e. 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 ~ 1970) </p><p>  The ea

6、rly 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 can not but use numeral logic circu

7、it "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 Chengwei numerical control (NC). Al

8、ong 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 general minicomputer already appea

9、red 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 ("which should have computer in front

10、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 the large scale integrated circuit

11、technology integration </p><p>  The microprocessor is applied to 1974 in the numerical control system. This is because minicomputer function too strong, controlled an engine bed ability to have wealthily (t

12、herefore 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 ide

13、al. 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 had called microcomputer) the perfo

14、rmance 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. </p><p>  In brief

15、, the computer numerical control stage has also experienced three generations. Namely 1970 fourth generation of -- minicomputer; 1974 five dynasties -- microprocessor and 1990 sixth generation -- (overseas was called PC-

16、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 out, although overseas already renam

17、ed 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 materially already was refers to "comp

18、uter 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 PC sixth generation of direction &

19、lt;/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 onto this path. Uses PC machine to tak

20、e 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 numerical control duty by the orig

21、inal 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 the service will be more common. &l

22、t;/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 develop. </p><p>  1.3.3

23、develops to the intellectualized direction </p><p>  Along with the artificial intelligence in the computer domain unceasing seepage and the development, the numerical control system intellectualized degree

24、unceasingly will enhance. </p><p>  (1) applies the adaptive control technology </p><p>  The numerical control system can examine in the process some important information, and the automatic co

25、ntrol system related parameter, achieves the improvement system running status the goal. </p><p>  (2) introduces the expert system instruction processing </p><p>  The skilled worker and expert

26、'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 intelligence the expert system. </p>&l

27、t;p>  (3) introduces the breakdown to diagnose the expert system </p><p>  (4) intellectualized numeral servo drive </p><p>  May through the automatic diagnosis load, but the automatic contr

28、ol parameter, causes the actuation system to obtain the best movement.</p><p>  Second, engine bed numerical control transformation necessity </p><p>  2.1 microscopic looks at the transformatio

29、n 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, moreover these superiority come from th

30、e 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 the complex components.</p>

31、<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 exercise, therefore may turn round

32、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 enhance 3 ~ 7 times compared to the tradi

33、tional 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 according to the procedure automatic

34、 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 unit and the small batch of produc

35、tion can automate, therefore is called has realized "flexible automation". </p><p>  2.1.3 processings components precision high, size dispersion degree small, makes the assembly to be easy, no lon

36、ger needs "to make repairs".</p><p>  2.1.4 may realize the multi- working procedures centralism, reduces the components in engine bed between frequent transporting. </p><p>  2.1.5 ha

37、s 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><p>  2.1.6 advantage which de

38、rives 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), reduced the work clothes, reduced

39、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 predecessor cannot imagine, is an extre

40、mely significant breakthrough. In addition, the engine bed numerical control carries out FMC (flexible manufacture unit), FMS (flexible manufacture system) as well as CIMS (computer integration manufacture system) and so

41、 on the enterprise becoming an information based society transformation foundation. The numerical control technology already became the manufacturing industry automation the core technology and the foundation </p>

42、<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 industry, in the end of the 70's

43、, 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 (including the armed forces, airplane weapo

44、n industry) carries on the technological transformations. Except that uses outside the numerical control engine bed, FMC, FMS in the manufacture process, </p><p>  Thord, the numerical control transformation

45、 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 bed transforms took the new economic

46、al 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 "the eternal" topic. Our countr

47、y'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 mark</p><p>  3.2 Numeri

48、cal control transformation content </p><p>  The engine bed and the production line numerical control transformation main content has following several points: </p><p>  First is extensively rec

49、overs 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 reveals the installment on the ordinar

50、y 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 efficiency and the automaticity, to the ma

51、chinery, the electricity partially carries on renovates, reassembles the processing to the machine part, extensively recovers the precision; Does not satisfy the production request to it the CNC system to carry on the re

52、newal 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 new technology, carries on the big

53、 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 system transforms after, how carries on

54、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 </p><p>  3.3.1 reduce

55、d 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 is low. Large-scale, the special eng

56、ine 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 peculiar circumstances, like the high sp

57、eed 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 stable are reliable, the structure is l

58、imited </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 transformation engine bed performance high, the

59、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><p>  3.3.3 familiar understoo

60、d 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 processing request. The transformation then

61、 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 services the aspect to train the tim

62、e 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 existing condition </p><

63、;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 control technology </p><p>

64、;  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.</p><p>  Fourth, numeric

65、al 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 carry on the choice. </p><p&

66、gt;  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 step-by-steps the electrical machine

67、ry, 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 power enlargement, causes to step-by-st

68、ep 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>  This system structure simple, debuggi

69、ng 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 grating survey feedback closed loop nume

70、rical 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 grating, induction synchromesh obtains

71、, 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 turns towards the elimination deviation

72、 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 the split-ring, the cost is also h

73、igh, 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 a system higher precision, quicker

74、 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 current servo electrical machinery dri

75、ves, 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 surveys the executive component th

76、e 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 the debugging all compares the closed

77、-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 production numerical control system c

78、ompany factory quite are many, overseas famous company like German SIEMENS Corporation, Japanese FANUC Corporation; Native corporation like China Mount Everest Corporation, Beijing astronautics engine bed numerical contr

79、ol system group company, Central China numerical control company and Shenyang upscale numerical control country engineering research center. </p><p>  When choice numerical control system mainly is each kind

80、 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>  Fifth in the numerical control transf

81、ormation 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 rigidity; Movement vice- between friction

82、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 above requirements as far as possibl

83、e. 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 </p><p>  Said to the

84、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 attrition characteristic, and the

85、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 influence, must have the reasonable guid

86、e 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 gear box. In order to guarantee the

87、 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 in the structure, thus transforms

88、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 screw and the ball bearing guide scr

89、ew </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 request in the job precision. Is not

90、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 well as matches the nut gap. The or

91、dinary 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, its transmission efficiency may above

92、 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. Therefore may satisfiedly compare the high

93、 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 must take the corresponding measure a

94、ccording 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 scrap and the hard sand grains ent

95、ers 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>  Sixth, After the engine bed ele

96、ctrical 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 programmers to be extremely importan

97、t, after otherwise will affect the transformation the engine bed rapid investment production. The training content should include the new operation kneading board disposition, the function, the instruction meaning genera

98、lly; New system functional sc</p><p>  the numerical control transforms se Transforms the scope according to each equipment differently, must beforehand design the connection partial transformations, if tran

99、sforms completely, should design the electro-mechanical transformation connection, the operation kneading board control and the disposition, the interconnection partial contacts, the parameter measuring point, services t

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