The stage amounts to servo to process the application on the machine tool in silk of don't go yet
- source:NODIE CNC Machining
The follow error that 2rpm exceeds low speed to run process middleman and guarantor to maintain stability and big inertia servo are debugged give out to discuss mainly. Keyword: Line cut stage amounts to Electromechanical big inertial servo line cut machines 1 foreword electric spark (WirecutElectricalDischargeMachining, abbreviation WEDM) , call a line cut again sometimes. Its work basically the principle is the fine wire that uses successive shift (call electrode silk) make electrode, undertake to workpiece corrode of pulse scintilla discharge shapes except metal, cut. Line cut basically is used at processing all sorts of form complex with accurate and petty workpiece, develop the punch that reduces a standard, sunken model, punch-die, fixed head, discharge board to wait for example, the metal electrode that processing of figuration cutting tool, example, electric spark uses, all sorts of imperceptible aperture chamfer, narrow seam, aleatoric curve, have mental allowance precision of small, treatment tall, production is periodic short, production cost is low and outstanding advantage, already aborning wins wide application, at present machine tool of domestic and international cut of electric spark line already occupied report to machine the 60 ％ above of machine tool gross. Silk of 2 don't go yet machines a machine tool 2.
Classification of machine tool of 1 line cut differs according to the traversal speed of electrode silk, normally cent is machine tool of cut of electric spark line two kinds: One kind is high speed takes a machine tool of cut of electric spark line (WEDM-HS) , its electrode silk makes high speed reciprocate, average rate walking along silk is 8 ～ 10m/s, electrode silk can repeat use, treatment rate is higher, but walk along silk to cause electrode easily quickly silk shakes and retrorse when halt, make machine quality to drop, it is our country production and use main machine are planted, the cut of electric spark line that also is our country original creation machines mode; Another kind is low speed takes a machine tool of cut of electric spark line (WEDM-LS) , its electrode silk makes low speed one-way motion, average rate walking along silk under 0.
2m/s, after silk discharges, electrode is used no longer, the job is smooth, even, shake quality of small, treatment is better, but treatment speed is inferior, it is foreign production and use main machine are planted. Of article introduction is the applied case that the stage amounts to ASD-AB servo to machine a machine tool to go up in silk of don't go yet. If the graph is shown 1 times,silk of don't go yet machines a machine tool. If the graph is shown 2 times,the work that machine tool of silk of don't go yet processes pursues. Graph silk of 1 don't go yet machines a machine tool 2.
Silk of don't go yet of structure of machine tool of 2 lines cut and walk along silk quickly to include as the component with treatment main machine tool: (1) lead plane: Include workbench of lathe bed, coordinate, orgnaization walking along silk to wait; (2) pulse power source: Change alternating current into the one-way pulse electric current of certain frequency; (3) machine tool of control system control moves, it is the key of article discussion; (4) working fluid circulatory system: Offer cleanness, the working liquid that has constant pressure. Graph the work that machine tool of silk of 2 don't go yet processes pursues the 3 motion that are based on a stage to amount to servo technology are controlled 3.
1 hardware introduction controls a part to go up namely an engine system and servo: (1) go up a machine: It is the machine tool of silk of don't go yet that is based on PC framework special NC controller; (2) servo: Two stages amount to ASD-AB10212MA servo controller and stage to amount to electric machinery of servo of ECMA-G31309ES big inertia. (3) mechanical drive: Servo electric machinery is even pitch the filar lever of 6 Mm continuously. 3.
The main technique difficulty of the servo application on machine tool of silk of don't go yet of 2 technologies difficulty is in namely 0.
2rpm exceeds the follow error that low speed maintains firm in moving process, at the same time follow error must be less than 2 pulse again. Such exceeding requirement of low speed technology is with the treatment of machine tool of silk of don't go yet the characteristic has close connection actually. The electrode silk diameter of machine tool of silk of don't go yet normally 0.
35mm, and summation can amount to the area that line of the center when its process work has cut on workpiece to be Min of 350m ㎡ ／ about most, the work that machine tool of silk of don't go yet processes and walking along silk quickly to differ is normally have very big treatment ply very high to machining precision to ask again already. This has very high demand to the feed speed of machine tool of silk of don't go yet, speed must be inside certain limits, too rapid rate can cause treatment not complete, the coarse trace with differ depth stays to make exterior surface roughness becomes poor in workpiece surface, also can cause electrode silk vibration to increase at the same time, easy cause fracture of wire! Be less than the follow error of 2 pulse as to servo, because the treatment principle of line cut is discharging ceaselessly between negative electrode namely,be calcination workpiece surface, that is to say should maintain certain distance between two electrode, both neither can be contacted together cause short circuit, cannot be apart from again cause open circuit too far! Servo of 4 big inertia is debugged 4.
1 system is debugged can saying to debugging a process is difficulty heavily, because the client is mechanical integral load is exceedingly big, and machining water of the flood in groove in the process of treatment even, make laden inertia and laden quality greater, increased the control difficulty of servo. To assure 2 pulse track an error, so the gain of servo controller must be maintained in a higher level, but because allow to appear scarcely any oscillatory, so the gain of servo control system still cannot pass quite big, that is to say in stable response level and stable control are spent evenly between search a balance to nod, this balance nods choosing is the key that we debug. The traversal speed 200rpm that because the traversal speed of this equipment cannot exceed us to debug software appraise to measure laden inertia place,needs, can pass ceaseless test only so, undertake installing to parameter, in order to find first-rate gain parameter, dominate the 2-00(niche that concerns with gain in servo parameter gain) namely, 2-02 (gain of the make a present of before the position) , 2-03 (gain of the make a present of before the position is flowing constant) , 2-04 (speed controls gain) , 2-06 (speed integral is compensated) , and the 2-25 that concerns with resonance (resonance restrains the low wave that connect filter) , 2-23 (resonance restrains Notchfilter) , 2-24(resonance restrains Notchfilter attenuation to lead) undertake experimenting ceaselessly to install and run a test, 2-00 main effect maintains positional annulus control to answer a level, 2-04 main effect maintains speed annulus control to answer a level, these two values are the foundation that servo answers, and the main effect of 2-02 and 2-06 reduces the position to control speed of sum of errors to control an error namely, these two the value moves very high position to be able to reduce follow error apparently. 2-03 action is OK greatly the movement that reduces main transfer machinery is oscillatory. When just beginning to debug, very fast the top control level that with respect to the response servo the level adjusts not to make servo report accident has vibration all right, the moving effect of electric machinery of the servo on this gain level is it is servo in 0.
Next moving follow errors carry the rate of 5rpm basically inside 2 pulse limits, but in what move some a few are nodded when, can jump change 3~4 pulse. This is moving unallowed of equipment of silk of don't go yet, must improve such moving result through adjusting the gain of servo, because of such follow error jump because on a certain operating point the laden circumstance of servo produces a change,changing is, and the response as a result of servo not quite fast, just can appear so the circumstance that follow error greatens. Pass above analysis, in answering a level to cannot make servo electric machinery runs a course again, appear what raise servo namely what need implementation any oscillatory. Make electric machinery oscillatory for both neither, raise gain level again, increase 2-03 the vibration that reduces orgnaization drive only, the gain level position that just can improve 2-04 and 2-00 raise servo whole thereby is higher answer, in the meantime, still cannot adjust the value of 2-03 the ground is exorbitant, because it can affect the position,track an error. In add adjust already below very good case, begin to install workpiece to try cut. Trying cut a process to discover a very unusual appearance, be in namely X axis with 0.
When 3rpm speed feed, of Y axis track an error to be able to one jumps ceaselessly change, y axis does not have signal input at all at that time, should not have any shift. Appear such circumstance has two to plant only likelihood, it is to have signal interference, 2 was to produce mechanical vibration! Passing judgement is when moving with fixed rate in X axis, y axis can have resonance generation! Use us to debug software ASDA_A_SW to find resonance frequency, eliminate resonance, debug finish. If the graph is shown 3 times,resonance restrains the capture that frequency nods. Graph 3 resonance restrain frequency to nod 4.
2 workpiece test regards treatment as the machine tool, must try the applied circumstance that cuts the servo that proves us to whether can satisfy machine tool of silk of don't go yet through treatment. Graph 4 it is the workpiece effect graph that the stage amounts to ASD-AB servo to machine, graph 4 showing is to grinding layer of one part oxidation to detect later its surface is bright and clean degree, better and better from effect of treatment of date of a ~3, pure the face that sees 3 from treatment effect is bright and clean it is already OK to spend already with former servo the treatment effect of the electric machinery of high accuracy servo of 17 coder is close to. Graph 4 treatment try cut workpiece to check 5 last words the stage amounts to ASD-AB servo basically is respect of control of the feed in applying in control system, servo motion function how, immediate impact is worn the treatment precision of workpiece and exterior surface roughness. What the client uses so is the servo of foreign well-known trademark, its servo electric machinery is to use 17 tall lines to count coder, and the stage amounts to what ASD-AB servo uses is the ECMA electric machinery that form a complete set of ASD-B series servo uses, its coder is the servo coder that the small line of 2500 line counts merely. The silk of don't go yet of the servo that the treatment precision that applies a silk of don't go yet that amounts to ASD-AB servo to machine a machine tool and exterior surface roughness and client use 17 tall lines to count coder so the machine tool differs very few. Got below the premise that makes production cost of the client is not reduced in function thereby greatly compress, raised its product to machine the market competition ability of the machine tool in silk of don't go yet. CNC Milling