The functional characteristic of numerical control machine tool and classification

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One, function and characteristic (one) the main body that leader leader is numerical control machine tool, it is the mechanical part that is used at finishing all sorts of cutting to machine. Machine a requirement according to different spare parts, lathe, milling machine, drilling machine, boring machine, grinder, heavy-duty machine tool, report processes machine tool and other type. What differ with general accuracy machine tool is, because machine tool of most numerical control used high-powered main shaft and servo transmission system,the lead plane of numerical control machine tool has;l) of the following characteristic on the structure, accordingly, the mechanical drive structure of numerical control machine tool got simplifying, transmission cable length is shorter. 2) to get used to numerical control machine tool continuously automation treatment, structure of machinery of numerical control machine tool has taller dynamic stiffness, damp precision reachs wearability, heat is out of shape lesser. 3) uses efficient drive disk assembly morely, be like ball guide screw deputy, linear scroll slideway. (2) device of CNC (Computerized NumericaJ Contro1) the core that this is numerical control machine tool. With the part program that digitlizes at realizing an input, operation of the shift that finishs the memory that inputs information, data, interpolation and implementation all sorts of control functions.

The numerical control device of machine tool of contemporary numerical control is had below a few functions. 1) much coordinate is controlled () of much axis linkage. The interpolation that 2) realizes a variety of function (the) such as linear, circular arc, parabola. 3) code is changed (EIA/ISO code changeover, imperial / metric changeover, 2 - decimal changeover, absolute value / the) such as increment size changeover. Man-machine interaction, hand moves 4) data loses a person, machine program loses a person, editor and revise. 5) machines a choice, all sorts of treatment circulate, repeat treatment, sunken (protruding) modular treatment, mirror image treatment. 6) can realize all sorts of compensation functions, have the compensation of clearance of length of cutting tool radius, cutting tool, drive, pitch error. 7) realizes breakdown to be diagnosed oneself. 8)CRT or LCD show, implementation graph, contrail, character shows. 9) couplet net reachs communication function. (3) the drive component that actuating device actuating device is actuator of numerical control machine tool. The main shaft of general accuracy machine tool and feed system, basically implement motion and speed change by the gear of box of feed of electric machinery drive and main shaft box. And main shaft of numerical control machine tool and feed are by numerical control device issues feed statement, pass electric or electro-hydraulic servo comes true. When axis of a few feed achieved linkage, the machine tool can finish a point, the treatment of linear, flat curve or dimensional curved surface. Generally speaking, the servo drive of numerical control machine tool, ask to answer function what had had quickly, can acute and accurate dog to send the digital command signal that come by numerical control device. (4) the auxiliary unit of numerical control machine tool it is the component of form a complete set that makes sure function of numerical control machine tool develops a need adequately. The range that includes as a result of device of these form a complete set is very wide, have component of electric equipment, hydraulic pressure, pneumatic and bit of cooling, platoon, defend, lubricant, illume, store a series of device such as carry, it has very big effect to developing the function of itself of numerical control machine tool, because this got of each estate department take seriously, development is very rapid. (5) etc of Cheng white machine a few set machine tool of each contemporary numerical control accessorily, the keyboard that can use CNC device to go up not only loses the order of person spare parts directly, also can use automatic Cheng to make up machine, the to program of the spare parts has outside machine, get on program notes in information carrier (like punched tape, tape, disk, U dish wait for) , send numerical control unit next. To relatively complex part, it is to use this kind of method commonly. To this kind of means, we call voluntary to program, or the computer assists to program. Large, the part program of special curved surface, often want to come true with the computer, use the general periphery interface of the computer, if RS-232 strings together mouth, U dish what interface and memory card interface will have part program with CNC device is deferent. Reach the development of computer software technology as microelectronics technology now, the to program of most spare parts works, came true by the computer. Use to facilitate, a few companies still can offer a few appropriative Cheng to make up machine, deserve to have complete accessary facility. Cheng makes up use appropriative software, the work out of OK and convenient high quality gives the part program of all sorts of need. The software that machines the CAD process designing that applies more extensively in the industry in the mould at present has the famous software such as MasterCAM, Prole. 2, the classification of numerical control machine tool to numerical control machine tool, we can are opposite from different point of view its undertake classified. (One) classify by the characteristic that controls a system 1.

Machine tool of numerical control of dot position control uses numerical control machine tool to treatment of a few aperture, ask to obtain accurate aperture to fasten precision of coordinate fixed position only, and no matter arrive from an aperture,another aperture is move according to what kind of contrail, be like coordinate drilling machine, coordinate boring machine and punching machine, can use the system of dot position control with simple and low price. This kind orders position control system, locate well and truly to ensure, the system moves in high speed hind, use 3 class decelerate commonly, reduce fixed position error in order to decrease. But because move an itself existence is inertial, and when low speed moves, attrition force changes likely. After although actuating device stops,moving so, workbench does not stop instantly, form D of Δ of fixed position error, and this value has certain dispersive sex. 2.

Machine tool of linear control numerical control is certain numerical control machine tool asks to have not only decide definitely function, and the requirement arrives another a little bit from between by linear shift, can control the rate of displacement. Because the numerical control machine tool of this one type is in between 2 o'clock when shift, want to undertake cutting is machined. Mix to different cutting tool so workpiece, need chooses different cutting dosage and feed career. Does this kind numerical control machine tool include: ?  Mu Qiu fries Yao of ill ⑹  to swing ill ⒓ to need ぶ travel male takes 4 Mo of  of N of curtain of Piao of fan of Zhui of  of dumpling of Bao of reef of laborious of  of Bo of  of Tao of  of ┦ of Wu of brandish of You of a pavilion or house on a terrace of R word a side gate of an imperial palace to closely question  of buffalo gnat of Gua of poisonous Qin ニ is bad poisonous Yao Xi.

Machine tool of outline pilot numerical control more numerical control machine tools, have outline pilot function, can machine a curve namely or the spare parts of curved surface. This kind of machine tool has 2 coordinate and CNC Milling of 2 coordinate above, can machine the numerical control lathe of curved surface, machining center. Machine tool of this kind of numerical control should control two at the same time or the axis of two above has interpolation function, can have strict uninterrupted control to displacement and speed. Great majority of machine tool of contemporary numerical control has the function of two coordinate or linkage of two coordinate above, a series of compensation functions such as the clearance error compensation of compensation of error of motion of axial of compensation of compensation of radius of not only cutting tool, cutting tool length, organic still bed, guide screw, gear. According to but linkage (control at the same time) number of axle, and the number of axle of mutual independence, can have 2 axle control, 2.

5 axle control, 3 axle control, 4 axle control, 5 axle control. 2.

5 axle control (two axes are successive control, bed 3 axes are a dot or linear control) principle, realized X of 3 main axes, y, the two dimension inside Z are controlled. 3 axle control are X of 3 reference axis, y, z at the same time interpolation, it is three-dimensional and successive control. 5 axes are controlled continuously is a kind of very important treatment form, at this moment X of 3 linear reference axis, y, z, with the circumgyrate of revolving stage, of cutting tool swing, at the same time linkage (also can be the linkage of numerical control revolving stage with two axes, or cutting tool makes two way swing) . Because point of a knife can press mathematical rule to direct, those who make is perpendicular at any times doubler the curve is flat (Double Curve) , because this is special,agree with treatment lamina, wing. (2) the servo type that presses actuator is classified 1.

Machine tool of numerical control of open loop servo this is machine tool of more primitive a kind of numerical control, after the numerical control system of this kind of machine tool handles the order of the spare parts, output number command signal gives servo, drive machine tool moves. Did not come from the feedback signal of positional sensor. The most typical system uses a pace to enter the servo of electric machinery namely. This kind of machine tool relatively economy, but speed and precision are inferior. Accordingly, be in at present home, still serve as a kind of economy model numerical control machine tool, multi-purpose at to old machine tool transform. 2.

This kind of machine tool can accept machine tool of numerical control of closed circuit servo interpolation implement instruction, and the signal of real position feedback that accepts workbench end to be measured at any time undertakes comparative, differ a value to undertake the error is amended ceaselessly according to its. The precision error that machine tool of this kind of numerical control can eliminate the presence in be being made as a result of drive disk assembly machines brought influence to workpiece. This kind uses the numerical control machine tool of closed circuit servo, can get very tall treatment precision, but as a result of a lot of mechanical transmission link, like guide screw deputy, workbench includes to be inside feedback annulus road, and all sorts of mechanical transmission link, the attrition that includes guide screw and nut, workbench and guide is characteristic, the tigidity of each component, and the transmission catenary interval that displacement measures component to install is waited a moment, it is alterable, the adjustment that affects servo directly parameter. Have the parameter of linear of a few dispute, because design and be adjusted of system of this closed circuit,have greater difficulty. Design and adjust badly, what form a system very easily is not stable. So, machine tool of numerical control of closed circuit servo, basically use at a few precision to ask very expensive boring milling machine, lathe exceeding essence of life, milling machine exceeding essence of life. 3.

The machine tool of numerical control of great majority of numerical control machine tool of servo of half closed circuit is servo of half closed circuit, will measure component to move from workbench electric machinery termination or guide screw termination. Guide screw, nut does not include inside the road of closed circuit annulus of this kind of system deputy reach workbench, the control character: that can you gain stability accordingly?  fact of straight Yuan of Le of bright of be ignorant of of take along sth to sb of deceive of take along sth to sb seeks tip of  of  of  of throat putting in order to say  of wood of badger of the  below Song cap Ran lights 8 Yu to take? 3) classify by type of numerical control device 1.

Machine tool of hardware type numerical control (namely NC machine tool) this is inchoate numerical control machine tool, numerical control device is defeated by person, operation, interpolation operation and control function mediumly to all be comprised by the parts of an apparatus such as integrated circuit or transistor. Generally speaking, different numerical control machine tool needs to design different logistic circuit technically. The versatility of device of numerical control of machine tool of this kind of numerical control is poorer, because its are comprised by hardware entirely, function and flexibility are so poorer also. Accordingly, this kind of machine tool is used basically already now no longer. 2.

Machine tool of software type numerical control (namely CNC machine tool) 70 time metaphase, as the development of microelectronics technology, of chip compositive degree taller and taller. Use medium, large-scale reach exceed large-scale integrated circuit, compositive CNC device becomes a possibility. Use the numerical control machine tool of this kind of device, its main function, come true almost completely by software, to different numerical control machine tool, need to weave different software can come true only. And hardware is almost OK and general. This was the big batch production of hardware to offer a condition. The quality that batch production is helpful for assuring a product, shorten production is periodic, reduce manufacturing cost, show machine tool of acting numerical control so, use CNC device. Numerical control of type of this kind of software, because have very tall flexible, the user that gives a machine tool factory and machine tool with very big convenience. They can give different user order according to respective need development, make the application of numerical control machine tool more wide, can arrive deep the equipment of machining course of study go in the domain. (4) by treatment means is classified 1.

Metallic cutting class number charges a machine tool: Wait like boring machine of grinder of drilling machine of numerical control lathe, machining center, numerical control, numerical control, numerical control. 2.

The metal shapes kind of numerical control machine tool: If numerical control folds compressor of head of circumgyrate of pipe bender of curved machine, numerical control, numerical control,wait. 3.

Numerical control non-traditional machine tool: Exactly the amount controls a route (electrode) laser of machine tool of cut machine tool, treatment of numerical control electric spark, numerical control (plasma) cut machine tool. 4.

The numerical control machine tool of other type: Like blaze cut machine, numerical control 3 coordinate are measured machine. (5) classify according to functional level can you be cent of numerical control machine tool tall, medium, cheap (economy) 3 kinds of: ? Hut location casts carapace of  of ǎ of Ku any of several hot spice plants  of  of Bo of Du of dusk of Mei of  of bully Xuan night and blame of Wu of Xing Huan of leech  brandish fetterses Ang of a key to do sth of cheek of N of two of acenaphthene evil spirit knocks at delay of mu of Liao of  of courtyard of  of ㄒ Dan  collect of an ancient type of spoon looks for  of Qin of charm deer δ to irrigate.

Resolution and feed speed: Resolution is 10um, feed speed is 1um for cheap; resolution in 8 ~ 15m/min, feed speed is for 15 ~ 24m/min intermediate; resolution is 0.

1um, feed speed is 15 ~ 100m/min is tall crotch. 2.

Servo feed type: In using open loop, pace to be cheap; into system of electric machinery feed high-grade the dc servo that uses half closed circuit and communication servo (also include to use) of closed circuit servo. 3.

Linkage number of axle: Most linkage number of axle is machine tool of cheap numerical control 3 axes of 2 ~ , medium, high-grade it is 2 ~ 4 axes or 5 axes of 3 ~ above. 4.

Communication function: Cheap numerical control does not have communication function commonly. Intermediate and OK direct figure of RS-232 or DNC (Direct Numerical Control is controlled) interface. High-grade still can MAP(manufacturing Automation Protocal makes automation agreement) communication interface, have couplet net function. The CNC device of the near future still has memory card and U dish interface. 5.

Indication function: Cheap numerical control is ordinary only simple digital tube shows or basic message of simple CRT, LCD shows. And intermediate numerical control has information of more all ready CRT, LCD to show, have character not only, and have a figure, man-machine interaction, diagnose oneself wait for a function. High-grade numerical control still can have three-dimensional graph to show. 6.

Outfit PC(programmable Contro11er can make up Cheng controller) inside: Cheap numerical control is not had commonly inside outfit PC, medium, high-grade numerical control has inside outfit PC. High-grade numerical control has strong function inside install PC, have the patulous function of axle control. 7.

Advocate unit) handles in the center of CPU(centraI Processing Unit: Cheap numerical control uses 8 CPU commonly, intermediate reach high-grade transfer already stage by stage to 32 CPU by 16 CPU. At present a few new numerical control systems of abroad had chosen 64 CPU, processing is unit in the center of the RISC that chooses appliance to have compact instruction market, in order to raise operation rate. According to a few functions of above and index, can distribute the product of all sorts of types for low, medium, high-grade system of 3 kinds of numerical control. CNC Milling CNC Machining