First, CNC computer carving machine and numerical control mill, processing center contrast

1. Machine part

The general engine bed machinery generally all divides into two parts: Namely the migration are partial and the non- motion part, the work table, the main axle slide and so on for moves the part, the lathe bed, the foundation, the column and so on for the non- motion part.

(1) numerical control mill, CNC processing center

The numerical control mill, the CNC processing center non- motion part and the motion partial rigidity all request extremely high, therefore can carry on 重切�? But because moves partially similarly huge, has sacrificed the engine bed flexibility, and is quick regarding the tiny cutting 速进 for appears lacks the ability to do what one would like.

(2) the CNC computer carves the milling machine

Carves the milling machine the non- motion partial rigidity request also to have as far as possible good, but moves the partial rigidity to have take to be nimble as the premise, must design dexterous somewhat as far as possible, simultaneously maintains the certain rigidity. So designs the CNC computer carving machine to be allowed to carry on the quite tiny precision work, the processing precision higher, may carry on the high speed processing regarding the soft metal, but because moves the partial rigidity worse, therefore is impossible to carry on 重切�? How therefore solves the motion partial weights from the mechanism also to be light, the rigid good contradiction, the key lies in the mechanism the time. Below here may use the method:

1) designs uses the ultra width the column and the crossbeam, because Dragon Gate's -like structure has the extremely good symmetry and the extremely good rigidity, it is the high-speed cutting equipment first choice structure. Compares with the traditional C lathe bed structure, Dragon Gate form lathe bed rigidity higher, stress average, work piece only in a end motion, each 运动�?and relative inertia low, the design compact is precise, guarantees the high rigidity, the high accuracy and the high dynamic characteristic. The engine bed crossbeam may use inclines 30 structures, causes the host 轴鞍 place the center of gravity moves to the rear area, and causes the crossbeam the guide rail spacing to enlarge as far as possible, so greatly enhances the main axle the stability and the rigidity. Because the column quality is bigger than the main axle and so on to move the part by far the quality, therefore has provided the solid safeguard for the engine bed high speed movement and the main axle high-speed operation and the load cutting.

2) the foundation uses the cast iron overall casting to become, uses the netted box overhead construction which the height muscle coordinates, or directly uses the honey-comb the docking in hexagon network structure, the foundation must have the certain weight to increase the engine bed the stability, the so high rigid foundation design may guarantee to the fixed work table and the column as well as the saddle place, the main axle and so on moves the part the rigid support, causes the engine bed dynamic processing the stability best, 全行�?in the scope completely supports the column, causes the distortion quantity which the processing produces to be smallest.

3) partially had regarding the migration with the numerical control mill is remarkable similarity is widened between very many guide rails and the guide rail distance, overcame not the good moment of force the question.

4) because the engine bed rigidity mainly uses in overcomes the migration partially when the high speed migration to the non- motion partial formidable impacts, therefore the guide rail, the lead screw request thick somewhat, as well as strengthens the connection partial rigidity, finally, in order to adapt high speed and the load cutting dual request, the X/Y/Z three axle all uses the servo electrical machinery to raise precision flexible coupling connection high accuracy ball bearing guide screw, all guide rails and the guide screw use the high-grade low friction coefficient, the high hard level quality product, both has guaranteed under the heavy load the engine bed rigidity, and had guaranteed the high speed movement precision, guarantees the engine bed under for a long time continuously the high speed processing condition low attrition and the precision retentivity, Saves the user the maintenance maintenance costs.

5) regarding numerical control mill and CNC processing center, because the request outputs the low rotational speed great torque, therefore the certain need main axle gear box decelerated recently promotes the torsion, therefore the rotational speed was low was inevitable, general numerical control mill and CNC processing center highest rotational speed 6000r/min, therefore not greatly possibly used the very small radius the cutting tool. But said regarding the CNC carving machine that, the main axle usually only then may work in 2 ~ 30,000 r/min, rotation precision general 2 mu about, otherwise breaks the knife phenomenon to be able to be very serious, therefore certainly must use electricity the main axle or the air operated main axle, namely the electrical machinery and the main axle are a body, also the main axle dead plate generally all uses light quality material and so on alloy aluminum. Says regarding the high-speed cutting equipment, requests the Inner Tibet type electricity main axle, moreover when low rotational speed also must use the certain torque, must have the perquisite refrigerator to maintain the main axle operating temperature to be constant, the main axle power must above 7.5 ~ 8kW, the rotational speed have to surpass 25000r/min.

2. The numerical control are partial

The numerical control mill, the CNC processing center is ordinary to the numerical control system request speed, about main axle rotational speed 0 ~ 6000r/min. But carves the milling machine request high speed numerical control systematic as well as the extremely good servo electrical machinery characteristic, about main axle rotational speed 3,000 ~ 40000r/min. The present high speed numerical control system, operates the platform generally is Windows, its performance all has the very big enhancement, not only processes high speed, is steady, moreover may with the domestic and foreign each kind of carving machine, processing center compatible use programming software, directly support the G code which MasterCAM and so on many kinds of CAD/CAM software produces. The numerical control system simultaneously has the following function:

(1) automatically to knife function: Target homing center, corner, depth. The precision is extremely high, solves the difficult problem which the mold adjusts.

(2) automatic/manual processing: Supports ISO the standard the G instruction, also supports through the engine bed input device, like grasps the equipment and so on to operate the engine bed, simultaneously in inlays supports through the computer input equipment, like the keyboard, the mouse complete the manual operation.

(3) the increase enters for and enters for the percentage on-line adjustment function: The convenient user precisely establishes for the quantity, also the length of stride and enters for the percentage may nimbly adjust.

(4) user data feeds (MDI) function: The user may on-line lose A the G instruction and carries out immediately.

(5) on foot pattern: The user may the processing duty which must carry out establish as on foot the pattern, thus restored for the wrong diagnosis and the breakdown has provided the good support.

(6) high speed smooth speed connection characteristic: Auto-adapted decided the current instruction links up the speed with during the next instruction. Not only greatly enhanced the processing efficiency, moreover improved the workability, eliminated has kept the processing surface the speed to meet 刀��.

(7) three dimensional conformable display function: Through the simple operation may from each angle observation three dimensional processing result, thus may more accurate, be more direct-viewing to processes the result to have the understanding.

(8) simulation function: May carry on the fast simulation processing to the processing procedure, can complete in the extremely short time, simultaneously inspects the processing procedure whether makes a mistake, whether the processing result does satisfy, and can the accurate computation actual processing need time.

3. Programs software

(1) diverse two-dimensional design

Present carving software like Type4, provided the formidable graph to found, the edition, the typesetting function, precise cartography and artistic cartography function, formidable language processing function. Has the many kinds of free curves the artistic writing arrangement effect, the font and the size wilfully adjusts, the edition; The formidable pitch point 编修 function, may be fast repairs and maintains the outline at will the partial shape.

(2) nimble three dimensional design

Relief carving software and so on Type4 provided has been convenient, quickly has the three-dimensional model formidable function by the two-dimensional graph, by the two-dimensional curve structure intense art effect artistic relief, the complex curved surface, and the artistic relief and the surface modeling perfect union, caused it to produce the shape complex carving product. Also might the direct output two-dimensional, the three dimensional cutting tool way, in the cutting tool way provide rough machining, half precision work, precision work and cutting tool way function and so on simulation.

(3) formidable CAD modelling design

CAD/CAM mold design and manufacture software and so on MasterCAM are at present machine-finishing profession widely uses also quite successful software, not only has the precise plan two-dimensional and the three dimensional graph function, but also may from this have the curved surface, the full-scale mockup and so on the formidable function, moreover has to the graph, the curved surface, the full-scale mockup direct establishment cutting tool way, confirms the NC formula through the simulation cutting tool way, by the computer input CNC computer carving machine, the numerical control engine bed completes the work piece the processing formidable function.

(4) facilitates data exchange function

Between software may directly carry on two, the three dimensional data transformation. The CNC carving machine and the CNC processing center and the numerical control mill are same, its processing foundation is the computer-aided design data. This is carves the CAD function the key to be at. At present the domestic and foreign quite advanced computers carve software function each has its strong points. Says from the software angle, the numerical control mill, the CNC processing center, the CNC carving machine all may use the standard CAD/CAM software, like Pro/ENGINEER, MasterCam, Cimatron, UG and so on. In the production, usually using Pro/ENGINEER, MasterCAM and so on advanced CAD/CAM software first carries on the product the 3D graph design, then draws up the numerical control processing craft according to the product characteristic design, the input processing parameter, produces the cutting tool way, the production processing procedure and transports to the numerical control engine bed control system carries on the automated processing. In the actual production, we have fully used the CNC computer carving machine which my school independently designs, procedure transports MasterCAM the establishment CAM to the carving machine control system processes the mold the copper electrode and small 钢件, because the carving machine rotational speed reaches as high as 40000r/min, enters for rate very is also high, greatly enhanced the processing efficiency and the quality.

Chart 1 CNC four axes computers carving machine

4. knives storehouses from move the knife and entire automatically to the knife

The processing center is for complete the many kinds of working procedures to the automatic condition numerical control equipment, mainly is regarding some fixed mass production works. But surely do not have often to process the center regarding the mold profession and the small volume production unit in, very many factories buy the processing center when the numerical control mill uses. The use knife storehouse says to the numerical control system cost very simply, but the main axle and the knife storehouse, the air compressor as well as each kind of hilt and so on can increase the cost, moreover programs, the adjustable cutter storehouse also must spend the corresponding time. Therefore, as far as possible do not have to use the processing center regarding the productivity identical variety to 1,200 work pieces, the cost high, the efficiency is low. May use entire automatically to the knife system, a knife upward attire, a button, the engine bed automatically to the knife, the direct processing, the error in 0.001 ~ 0003mm in, with from moves the time to come compared to, slow were very many. If processes the center, but not automatically the engine bed which installs to the knife with does not bring the knife storehouse, but has automatically the engine bed which installs to the knife to compare, in practice efficiency latter far is higher than former. Regarding the domestic manufacturing industry, specially the mold production enterprise said that, generally all is the piecework, moreover the labor force resources is sufficient, therefore, regarding the small batch industry components processing, must fully consider the fund the use value, do not have frequently to use the processing center equipment. Much less the domestic factory knife storehouse basically also has very many problems.

Chart 2 DYNA processing center

Second, application strategy

Along with technical changing with each new day, the CNC high speed engine bed obtains the mold manufacturers favour day by day, the high-speed cutting essence is the length which walks the cutting tool walks in the short time, as a result of its own fine characteristic, may large scale enhance the processing efficiency, thus may reduce the production cost. The high speed CNC processing center rotational speed may reach 40000r/min, at present the domestic use are more, the natural price quite good has German DMG to produce high speed machine. But the high speed machine use at present has very many problems, first is programs, the very many programmers in is high speed machine front frequently felt feels helpless at a loss, did not know how uses the cutting specifications, at present the most molds factory CNC programmers all are grow in the factory with skilled worker from the apprentice, they often have the rich experience, but lacks the system the theory instruction, to the cutting specifications understanding, often relies on is the experience and the feeling, but these experiences and the feeling are accumulates in the low speed CNC engine bed. Therefore, could not find facing the high speed machine-hour feels. Next also must consider the processing work piece the material and degree of hardness, the material is harder, the cutting specifications correspondingly takes the small value. Uses the cutting tool the performance very to be also important, because you choose the cutting tool decided you can use the rotational speed, had decided the engine bed processing is the ordinary processing or high speed processes. Therefore, only had has selected the high speed knife, could produce corresponding high speed, carried on the high speed processing. But the different company's cutting tool parameter also is widely divergent, therefore the programmers needs to process the cutting tool the related technical data. Compares with the ordinary low speed CNC engine bed, because the engine bed power is certain, main axle rotational speed quicker, its will be able to withstand 切削�?slightly, therefore time high speed machining, will eat the knife quantity to be corresponding must be small. Only has the engine bed, the cutting tool, the processing material, the processing nature and so on unifies can try to find out the best cutting specifications, has the best production efficiency.

Below in view of this kind of situation, after measures may use the processing craft: Because the present country suits 重切�?the engine bed very many, adds the labor cost also cheaply, the cutting tool is also cheap. But the common work piece process load is big, the precision request is not high. In view of the fact that this kind of situation, may use the profiling mill or the numerical control 铣把 majority of cuttings quantity completes (重切�?, is left over 2 ~ 3mm processing remainder, fast completes the surplus cutting quantity in the high speed CNC carving machine. After changes over to the high-speed cutting, because the processing object approached the forming, therefore first knife cutting quantity very even, may use the import the cutting tool, the cutting tool although expensively, but process period short, the cutting quantity is not big, therefore the performance price ratio is very good. Regarding the small mold, the processing remainder is not big, then may the complete processing duty all complete in the CNC computer carving machine. We fully used the CNC computer carving machine which my school independently designed to carry on the attempt, because the carving machine main axle rotational speed reached as high as 40000r/min, but effectively carried on the high speed processing. Uses in high speed to process the complex mold the cavity or the raised mold, may use the diameter is 8 ~ 10mm double edge round nose knife (permission line speed 380m/min) uses in the rough machining, with 6 ~ 8mm double edge 球刀 precision work. For example, high speed processes a small handset the mold, this components have many pressed keys and the screen concave cavities, is complex multi- curved surface typical components, the mold material is the T10 tool steel, the cutting tool for German Walter company's belt coating R3 double edge ball knife, cutting tool line speed 200m/min, main axle rotational speed 1.1 ~ 201,000 r/min, the cutting tool eats knife depth 0.5 ~ 0.8mm, enters for speed 5m/min, cutting tool gap quantity rough machining 0.5 ~ 5mm, precision work 0.1 ~ 0.2mm, the process period altogether 1 hour 12 minutes. Very many slight place must the clear angle processing, is unable the direct precision work, may process the copper electrode, uses electricity the spark working to complete. Uses in high speed to process the copper electrode which the electrical discharge machine uses, including the graphite electrode and the red copper electrode and so on, uses the corresponding cutting tool, may reach 3 ~ 8m/min in processing quite complex 型面 time entering for the speed, meanwhile has the very high processing precision. The above processing craft greatly enhanced the processing effect and the quality.

Third, concluding remark

At present, the numerical control technology development changes with each new day, but the CAD/CAM software development speed 远胜 to the engine bed CNC development speed, applies advanced software and so on Pro/ENGINEER, MasterCAM carries on the CAD/CAM design processing, respectively takes manager, and the final CAM procedure transmission for the computer carving machine execution, organically will unify the CNC computer carving and the CNC numerical control processing. The numerical control mill and the CNC processing center mainly uses in to complete an greater 铣削 quantity the work piece processing; But the CNC computer carving machine mainly uses in to complete a smaller 铣削 quantity, the work piece has a higher 表面�?fineness or the soft metal processing. Causes the CNC computer to carve into the mold to process the essential assistance processing method, has the widespread prospect and applies the market.