Detect the summary of commonly used method of malfunction of numerical control equipment

  • Time:
  • Click:648
  • source:EASCOR CNC Machining
Numerical control equipment is used now more and more extensive, subsequently and those who come is the effective utilization rate that how assures equipment, when equipment occurrence malfunction, should return to normal equipment as soon as possible use. To solve this problem, ask maintenance technician should have very high quality above all, not only the requirement has substantial professional knowledge, like technology of Electromechanical unifinication technology, computer principle, numerical control, PLC technology, accuse a technology oneself, procrastinate move technology of principle, hydraulic pressure to wait, master the simple process designing of machining common sense and numerical control device even, have certain English level even additionally, can read English technology material. Want to have enough data, include blueprint of machine, report, fluid, machine tool parameter backs up, the system uses maintenance manual, PLC echelon graph. Have the spare parts of certain amount even. Additionally need maintenance technician has certain experience, master regular maintenance method. The author pursues numerical control facility maintenance is old, accumulated certain experience, sum up a method that maintains numerical control facility, introduce as follows to consult in order to offer now. Should make clear breakdown phenomenon appears when numerical control equipment when breakdown, want to make clear breakdown phenomenon above all, to the operation personnel understands the situation when first time occurrence breakdown, the process of breakdown happening watchs below probable condition, watching trouble happen below what circumstance, how happen, cause what kind of consequence. Understand first-hand situation only, just be helpful for breakdown eliminate, made clear breakdown in process, the problem solves an in part. Made clear breakdown phenomenon, mix according to the machine tool next the working principle of numerical control system, OK immediately diagnose problem is in and trouble removal, make equipment returns to normal use. Be like, when a numerical control cylindrical grinder that uses system of Ⅲ of TEACHABLE of American BRYANT company is being machined automatically, nap of emery wheel general implement grind. Happen again to observe breakdown phenomenon prevents an accident, tear open emery wheel next moving machine tools, observe breakdown phenomenon again at this moment, discovery adds man-hour in automatic grinding, grinding does not have a problem normally, after workpiece grinding is over, when nap emery wheel, emery wheel is normal feed, and emery wheel nap implement rotate very fast, approach upper limit very quickly switch, if at this moment emery wheel was not torn open, affirmative emery wheel should bump into nap again implement on. According to the working principle of the machine tool, emery wheel nap implement drive by electric machinery of E axis servo, with rotate coder regards the position as feedback component. The nap below normal circumstance implement when nap emery wheel, z axis slip drives E axis nap implement shift arrives nap position, nap implement those who do ° of 30 ° ~120 swing come nap emery wheel. We observe breakdown phenomenon discovers for many times, e axis is in approach upper limit when switch, in the coordinate of axis of the E on screen the value has 60 ° left and right sides only, and real position is controlled in 180 ° probably, it is positional feedback occurrence problem apparently, but changed accuse board did not solve a problem with coder. We pass iteration observation and test again, discovery: E axis nap implement when the brim in Z axis, time reference point and rotate swing to do not have a problem, want those who use a system to call the police information diagnoses ability of numerical control system oneself now stronger and stronger, the system of major hitch numerical control of equipment can be diagnosed come out, take corresponding step, if stop machine, can arise commonly call the police show. When occurrence malfunction of numerical control equipment, show on monitor sometimes call the police information, go up in numerical control device sometimes, go up to still can have with actuating device on PLC device call the police directive. Should call the police to these according to manual at this moment information undertakes an analysis, some basises call the police information can confirm breakdown account directly, should make clear only call the police the content of information, with respect to the trouble that can remove numerical control equipment to appear. Be like, one uses the grinding machine of numerical control raceway groove of German SIEMENS810 system, 1 arises to call the police after switching on the mobile phone show " BATTERYALARMPOWERSUPPLY " , indicate numerical control system to cut off the power apparently protective batteries does not have report, change after new battery (attention: Must change below the circumstance with live system batteries) , breakdown restoration, the machine tool restores to use. Another uses the numerical control grinding machine of SIEMENS3 system, the screen after switching on the mobile phone did not show, inspect numerical control plant, discover diode of a glow twinkles, according to the manual, analyse its criticalflicker frequency, think to cut off the power truly protective batteries voltage is low, change after batteries, breakdown of the new system that start disappears. Be like, one uses the numerical control lathe of Japanese FANUC0TC system, appear 2043 call the police, show " HYD.

PRESSUREDOWN" , pressure of system of demonstrative hydraulic pressure is low. The basis calls the police information, undertake checking to hydraulic pressure system, discover hydraulic pressure pressure really very low, undertake adjustment making the machine tool restored to be used normally to hydraulic pressure pressure. Of another some of breakdown call the police the prime cause that information can not reflect trouble, reflect the perhaps poses from this as a result other problem of breakdown however, want to pass careful analysis and examination ability to determine breakdown cause at this moment, the method below reachs those who do not have a few breakdown that call the police to detect to this kind of breakdown is effective. The PLC position that should use numerical control system shows the function makes system of much numerical control PLC condition displays a function, be like the PCSTATUS that menu of 3 systems PC issues Xi Menzi, the PLCSTATUS function that menu of 810 systems DIAGNOSIS leaves Xi Menzi, and the PMC state that delivers function of DGNOSPARAM of system of that division 0T shows a function to wait, the instant position that uses these functions to be able to show the input of PLC, output, timer, tally to wait and content. The electric principle that offers according to the working principle of the machine tool and machine tool manufacturer pursues, carry surveillant and corresponding state, but diagnose a few breakdown. Be like, one uses the numerical control lathe of Japanese FANUC0TC, appear breakdown, switch on the mobile phone to appear 2041 call the police, indicate what X axis exceeds spacing to call the police, but observe X axis and did not exceed spacing, and the spacing switch of X axis also was not pressed fall, but the PMC position that uses NC system displays a function, the PMC that checks switch of X axis spacing inputs X0.

The condition of 0 is " 1 " , switch contact has put through really, demonstrative switch appeared problem, change after new switch, machine tool breakdown is eliminated. Be like, one uses the numerical control lathe of Japanese MITSUBINSHIMELDASL3 system, appear breakdown, knife tower does not rotate. According to the working principle of knife tower, when Dao Daxuan turns, rely on hydraulic pressure crock to have knife tower surplus above all, just can rotate next. Observe breakdown phenomenon, when the hand uses the button that presses Dao Daxuan turns, dao Dagen does not have reaction originally, that is to say, knife tower rises without float, according to electric principle graph, the output Y4 of PLC.

K44 comes to 4 control relay control electromagnetism a powerful person, electromagnetism a powerful person controls hydraulic pressure crock to make knife tower float rises, the PLC position that adopts NC system above all displays a function, observation Y4.

The condition of 4, should move Dao Daxuan to turn by the helper when pushbutton, its condition turns into " 1 " , without the problem, continue to check discovery, it is relay of its pilot dc the contact attaint of K44, change new relay, knife tower resumed normal work. The major hitch that the device of numerical control of PLC echelon graph that should use machine tool manufacturer to offer appears comes out through PLC device examination, PLC detects the PLC echelon that the mechanism of breakdown is specific machine tool to weave through running machine tool manufacturer namely pursues (namely program) , according to all sorts of inputs, output condition has logistic judgement, if discover a problem, generation calls the police and on monitor generation calls the police information. Produce the breakdown that call the police to a few PLC so, or a few breakdown that did not call the police, the echelon plan that can tell PLC of beyond the mark analyse undertakes diagnostic to breakdown, the ladder figure that uses NC system displays a function or the process designing outside machine implement online dog echelon pursues move, can raise the speed of diagnostic breakdown and accuracy. Be like, one uses the numerical control grinding machine of SIEMENS810 system, appear breakdown, the machine tool after switching on the mobile phone does not wind reference point and show without breakdown, the indicator light that examination Control Panel discovers to graduation device falls did not shine, this machine tool for safe for the purpose of, as long as graduation device is downfallen below, the feed axis of the machine tool cannot move. But examination graduation device, had fallen to do not have a problem. Offer PLC echelon plan according to machine tool manufacturer, the output A7 of PLC.

The graduation device on 3 Control Panel falls next indicator light. With process designing implement online observation echelon pursues move, discover F143.

4 did not close, cause A7.

The condition of 3 is " 0 " . F143.

Stage of graduation of 4 directives workpiece is falling next positions, continue to because input E13,check discovery.

2 did not close bring about F143.

The condition of 4 is " 0 " . According to electric principle graph, PLC inputs E13.

2 those who receive is to detect the immediateness that workpiece graduation device falls switch 36PS13, ravel graduation device, discover machine has a problem, the machine that cannot drive drive to be close to switch moves, so E13.

2 cannot close from beginning to end. After fostering cordial relations between states machine dimension, the machine tool restored to be used normally. One uses the CNC Milling of SIEMENS3TT system, in machining a process automatically circularly, workpiece already was machined end, workbench is rotating, main shaft has not been retreated reach the designated position, at this moment the 2nd labour main shaft stops turn, automatic loop is interrupted, generation calls the police F97 " SPINDLE1SPEEDNOTOKSTATION2 " with F98 " SPINDLE2SPEEDNOTOKSTATION2 " , represent the 2nd worker worker speed of two main shaft is abnormal. But undertake detecting to main shaft system and did not discover a problem. To determine breakdown cause, with the process designing outside machine implement trends monitors echelon of machine tool PLC pursues move, undertake checking according to logistic relation, final discovery is the 2nd labour work check tightens switch of hydraulic pressure pressure, e21.

Its condition produces the 1 moment in occurrence breakdown change, by " 1 " signal instant becomes " 0 " signal, back-to-back move becomes again " 1 " signal, e21.

1 those who receive is pressure switch P21.

1, its condition becomes " 0 " , signal directive workpiece is close without card, so main shaft stops turn, automatic loop stops. Be being tightened as a result of the card of workpiece is finished by hydraulic pressure, undertake checking to hydraulic pressure system, discover pressure is a little flabby, undertake adjustment to hydraulic pressure system, those who make is stable, the machine tool resumed normal work. Of this breakdown call the police because hydraulic pressure is flabby,what information mirrors is the main shaft that cause stops the phenomenon that turn, and flabby without reflective hydraulic pressure breakdown germ. Two kinds of methods are opposite above of breakdown of machine tool side detecting is very effective, because these breakdown no more than are to detect the damage of a powerful person of switch, relay, electromagnetism is mechanical perhaps executive construction occurrence issue, these problems are main OK according to PLC program, through detecting corresponding condition affirms breakdown is nodded. And when encountering trouble of a few systems, sometimes the case is more complex, the method that adopts in order to to fall and detect the principle can affirm breakdown is nodded quickly. Use commutative law to allow to locate breakdown is nodded truly to a few breakdown that involve control system, affirm which have a problem partly not easily sometimes, in ensure the circumstance that did not damage further falls, with reserve the control plate that control plate generation trades issue be havinged by suspicion, it is the efficient way that exact location breakdown chooses, the control plate crossing-over that goes up to control a system with the type with other machine tool sometimes will be faster diagnostic breakdown (want guarantee against to be able to damage good bat at this moment) . Be like, one uses grinding machine of the circle inside the numerical control of system of Ⅲ of TEACHABLE of American BRYANT company, appear breakdown, when E axis moves, appear call the police: "EAXISEXCESSFOLLOWINGERROR" , this meaning that call the police is E axis displacement follow the error exceeds set range. Because E axis produces this to call the police easily, e axis cannot wind reference point. The hand uses mobile E rod, observe breakdown phenomenon, when E axis moves, the change of E axis displacement shows on screen, when from 0 go 14 when, the numerical value on screen jumps suddenly change 471. Also be such when retrorse motion, should achieve - 14 when, also jump change 471. Appear at this moment afore-mentioned calling the police, feed stops. Classics analysis may be the problem of system of feedback of buy of E position of axle, this includes system of cable of E axis coder, join, numerical control accuse board and CPU of numerical control system board etc, to discover a problem as soon as possible, act on first simple hind complex principle, change above all accuse board, at this moment breakdown is eliminated. This machine tool another times X axis appears to call the police this, change above all accuse board, breakdown did not eliminate, because this suspects the attaint possibility of coder is larger, when the discovery when tearing open next coder, its shaft coupling already disconnected, change new shaft coupling, breakdown is eliminated. Should act on first the interior after periphery, first machinery hind is electric, first simple hind move after complex, Xian Jing, first public hind the special, fundamental that hardware examines after checking software first checks breakdown to appear to numerical control equipment more complex breakdown, when involving control system especially, apply these principles to be able to simplify the diagnostic process of breakdown, avoid crooked road. Sometimes these principles should be united in wedlock use, such ability make breakdown eliminates as soon as possible. Be like, one uses the numerical control grinding machine of SIEMENS3 system, when winding reference point, x axis cannot find reference point, axis of final occurrence X exceeds spacing to call the police, act on first the in-house principle after periphery, check X axis above all at 0 o'clock switch, do not have a problem normally, observe breakdown phenomenon, x axis approachs upper limit after switch, also can decelerate; Later basis first simple hind complex principle, examine NC system first accuse board, what use because of feedback hardware is grating feet, so v/arc be on the throne accuses board on, x axis, Y axis added an EXE to handle each board, above all the EXE X axis and Y axis board crossing-over, switch on the mobile phone at this moment test, it is normal that X axis winds reference point, breakdown move arrives on Y axis, y axis cannot find reference point, breakdown phenomenon is same, affirm EXE board has a problem thereby, change EXE board breakdown is eliminated. Be like, a numerical control that uses SIEMENS810 system quenchs machine tool, appear breakdown, switch on the mobile phone a reference point, when walking along X axis, appear call the police 1680 " SERVOENABLETRAV.

AXISX " , the hand moves X axis to also appear this calls the police, detect servo device, discovery has overload to call the police directive. The account that according to Xi Menzi the manual produces this breakdown is mechanical load occurrence breakdown of electric machinery of occurrence problem of power source of control of too big, servo, servo, act on first the electric principle after machinery, detect above all X axis slip, the hand is moved dish move X axis slip, discovery is very heavy, dish do not move, it is mechanical part for certain appeared problem. Tear open guide screw of X axis ball next detecting, discover ball guide screw is rustily already, it is slip so sealed and bad, quench fluid enters ball guide screw, those who cause ball guide screw is rustily, change trouble of new ball guide screw is eliminated. Be like, one uses the numerical control grinding machine of SIEMENS3 system, in machining a process automatically for some time, often midway stops to circulate automatically, and appear call the police 114 " SERVOLOOPHARDWARE " , demonstrative Y axis servo occurrence problem, explain according to manual, it is the issue that servo measures feedback system. To affirm breakdown further, act on the principle that uses after Xian Jing, the machine tool switchs on the mobile phone after winding reference point, the machine tool does not undertake any operations are in await condition, this opportunity bed does not appear call the police, when undertaking be machininged automatically, now and then appear this calls the police, and be every time appear when motion is controlled to 190mm call the police, what the positional feedback of the X axis because of this machine tool and Y axis uses is grating feet, its are derivative cable and slip move together, because this suspects this to cable often moves and make a few line break off, arrive in motion generation disconnects to call the police when proper place, confirmed this one judgement via the examination, change after new cable, breakdown is eliminated. This machine tool appears another times this breakdown, appear when dormant observation this calls the police, because this suspects control plate has a problem, will accuse board on the EXE of Y axis board the trade with X axis, switch on the mobile phone at this moment test, breakdown move arrives on X axis, the EXE that shows former Y axis board attaint, change new EXE board breakdown is eliminated. A few kinds introduced to detect above the commonly used method of malfunction of numerical control equipment, still can have a lot of other methods, but the problem that solves numerical control equipment to appear is the most crucial also is most the working principle that of core is the working principle that should master numerical control system and machine tool, when the problem that appears in equipment of processing numerical control so, ability handy, observation has to breakdown on this foundation, think, examination, analysis, diagnose, remove trouble finally. When nap implement when shift arrives among Z axis slip, the hand is moved rotate to appear breakdown. Conclude according to this phenomenon because the coder of E axis often follows nap,the likelihood is implement in Z axis shuttlecock, and the certain route that makes the cable of coder medium breaks off, bring about cable to follow nap implement the position is different, when Z axis brim, the contact is good, do not appear breakdown, and in Z axis among when, some line disconnect, lose feedback pulse. Be based on this kind of judgement, we begin school string, discover at this moment have a few line contact really undesirable, after finding line place, undertake solder and be adoptinged preventing folding measure to breaking a string, switch on the mobile phone afresh test, breakdown is eliminated, the machine tool restored to be used normally. CNC Milling CNC Machining