文献翻译-陶瓷全自动液压压砖机的plc控制系统

陶瓷全自动液压压砖机的PLC控制系统摘要介绍了陶瓷全自动液压压砖机的电气控制要求,PLC控制系统的组成,程序设计及抗干扰措施,这是一个实用的控制系统。全自动液压压砖机是建筑陶瓷行业中至关重要的设备,陶瓷粉料经压砖机压制成形,再经烘干,施釉,烧成后即为我们日常用的瓷砖。旧式压砖机通常采用继电器式的自动控制柜,存在结构复杂,体积大,故障率高,通用性差且控制精度不高等问题,严重影响了瓷砖的生产效率和产品质量。由于可编程控制器具有控制功能强、可靠性好、控制程序可随工艺参数灵活改变等优点,因此,近年来,无论是进口压砖机还是国产压砖机均采用PLC控制。关键词PLC压砖机控制系统1工作流程及控制要求液压压砖机的工作流程主要包括3方面推坯装料加压回程。其动作程序框图根据工作流程图,PLC控制系统主要完成以下要求实现压砖机生产过程各工步的顺序控制,且自动控制系统必须具有单步、单周期和连续控制3种功能。对各工步的时间、温度、压力额定值进行设置,具体参数由压制曲线决定。对冲压过程进行在线温度/压力检测及控制,并显示实时温度/压力值。必要的安全措施,如互锁,紧急停机,故障报警等。2系统组成与控制程序设计21PLC控制系统在本系统中,PLC既要控制主机的运行,同时要在线检测和控制时间、温度、压力等参数。因此,其输入设备主要包括方式选择开关,按钮,凸轮接近开关,旋转编码器等输出设备主要包括电磁阀线圈卸压电磁阀ES1、ES2,起压电磁阀EP1,增压电磁阀EP2等,接触器以及报警与显示信号指示灯等。综合输入/输出设备的点数,本系统选用日本三菱公司FX264MT型PLC,因为压砖机一般情况下昼夜工作且每分种的工作频率较高,所以我们选择晶体管输出这种方式,同时,FX2系列PLC具有功能强,用户程序存贮器容量大,智能程度较高等优点。22控制程序设计压砖机生产过程各工步的控制程序属于典型的步进顺序控制程序,我们可以用步进梯形指令STL指令很方便的绘出梯形图,而控制程序中许多在线参数的检测如压制次数,温度等程序则相对棘手,本文以每分钟压制次数的计数及压制次数的累计为例来说明此程序的设计,当M8000为ON时,上升沿微分输出PLS脉冲使M70得电,计数C为减数计数方式当M8000为OFF时,PLF脉冲使M72得电,计数C为加计数方式,M8014为表示/分0的数据寄存器。将C200计数器的数乘以2再存入C221中,梯形图中X021表示/活动横梁停止0的输入信号,Y013表示/锁模0的输出信号,压砖机每锁一次模,C220计一个数,这样总的压制次数也就自然累计出来了,梯形图中M103是用来启动高速计数器C252的信号,图中未画出C252的具体控制过程。本系统如果再配上上位机如386PC机,则可实现每分钟产品数量以及累计产品产量的动态显示。3抗干扰性分析由于大多数陶瓷厂工作环境较恶劣,粉尘多,噪声大,且PLC是24H不间断地工作,每分钟压砖机压制次数在17次左右,这样高频率的工作,PLC稍受干扰,将会使全厂全部停产,造成非常大的损失。因此,在本控制系统的设计中,PLC的抗干扰措施是我们着重考虑的问题,由于PLC的驱动元件主要是电磁阀和交流接触器线圈,为了提高系统的可靠性,我们在PLC输出端与驱动元件之间增加了光电隔离的过零型固态继电器ACSSR,PLC输出的控制信号经晶闸管放大,驱动ACSSR,ACSSR的输出经驱动元件连接AC220V电压,图中MOV为金属氧化物压敏电阻,用于保护ACSSR,其中电压在标称值电压以下时,MOV阻值很大当超过标称值时,阻值很小,在电压断开的瞬间,正好可以吸收线圈存储的能量,实践证明,这种抗干扰措施是非常有效的。4结语对于本系统自动控制操作的调试,首先应保证单步程序调试成功后,再转入单周与连续控制,且调试应在低压下进行,待上述步骤均调好后,再连接整个系统升压运行。由于PLC开发柔性好,可以灵活方便地进行编程和改变参数,因此,通过调整时间、温度等参数可以得到不同压制曲线,满足多种瓷砖生产工艺的需要。本系统已运行了多年,经我们跟踪调查,系统自动化程度高,抗干扰能力强,不仅提高了劳动生产率,而且大大减轻了劳动强度,得到了用户的好评。近期内我国墙地砖生产企业的主要奋斗目标将是企业走上良性循环的市场经济发展轨道,增加企业产品的市场竞争力,使企业获得良好的经济效益,因此,企业就必须花大力气开发别的企业不能生产或市场比较紧缺的特色产品。从技术上讲就是增加产品装饰效果,使产品的档次提高,从而提高产品的价值从装备上讲是使用较独特的装备生产别人生产不了的产品,最关键的就是选用2500T甚至更大吨位的压砖机。总之,在国内墙地砖行业陷人低谷、装备市场比较疲软的状况下,压砖机作为墙地砖生产必不可少的关键设备仍有较大的市场。技术过关,工作情况良好,售后服务及时可靠,备件供应齐全,将在很大程度上影响压砖机的销售。PLCCONTROLSYSTEMOFAUTOMATICHYARAULICPRESSFORCERAMICTILESABSTRACTTHEREQUIREMENTOFTHEELECTRICALCONTROLSYSTEMOFPRESSISINTRODUCEDTHEFORMATIONOFITSPLCCONTROLSYSTEMANDINTERFERENCERESISTANCEMETHODFORDESIGNINGPROGRAMAREDEMONSTRATEDASWELLFACTSHOWSTHATITISAUSEFULCONTROLSYSTEMAUTOMATICHYDRAULICPRESSUREBRICKMACHINEISCRUCIALINBUILDINGCERAMICINDUSTRYEQUIPMENT,CERAMICPOWDERCOMPACTINGBRICKMOLDINGMACHINE,THENTHROUGHDRYING,GLAZING,FIRINGAFTERDAILYUSECERAMICTILEFORUSTHEOLDBRICKMOLDINGMACHINEADOPTSRELAYAUTOMATICCONTROLCABINET,USUALLYEXISTCOMPLICATEDSTRUCTURE,BIGVOLUMEANDHIGHFAILURERATE,POORUNIVERSALITYANDCONTROLPRECISIONISNOTHIGH,SERIOUSLYAFFECTEDTHEPRODUCTIONEFFICIENCYANDPRODUCTQUALITYOFCERAMICTILEBECAUSETHEPROGRAMMABLECONTROLLERHASSTRONGCONTROLFUNCTION,GOODRELIABILITY,FLEXIBLECONTROLPROCEDURESWITHTHEPARAMETERSCHANGE,ETCADVANTAGES,THEREFORE,INRECENTYEARS,BOTHBRICKMOLDINGMACHINEIMPORTEDANDDOMESTICBRICKMOLDINGMACHINEADOPTSPLCCONTROLKEYWORDSPLCPRESSCONTROLSYSTEM1WORKPROCESSANDCONTROLREQUIREMENTSTHEWORKINGPROCESSOFTHEHYDRAULICPRESSUREBRICKMACHINEMAINLYINCLUDESTHREEASPECTSTHEPUSHSLABCHARGINGPRESSURETHERETURNTRIPTHEPROGRAMBLOCKDIAGRAMACCORDINGTOTHEWORKFLOWDIAGRAM,PLCCONTROLSYSTEMISMAINLYTOCOMPLETETHEFOLLOWINGREQUIREMENTSPRODUCTIONPROCESSEACHBRICKMOLDINGMACHINEWORKINGSTEPSSEQUENCECONTROL,ANDAUTOMATICCONTROLSYSTEMMUSTHAVEASINGLESTEP,SINGLECYCLEANDCONTINUOUSCONTROLFUNCTIONFOREACHWORKSTEPOFSETTINGTIME,TEMPERATURE,PRESSURERATING,SPECIFICPARAMETERSDETERMINEDBYSUPPRESSINGCURVESTAMPINGPROCESSFORONLINETEMPERATURE/PRESSUREDETECTIONANDCONTROL,ANDDISPLAYTHEREALTIMETEMPERATURE/PRESSUREVALUENECESSARYSAFETYMEASURES,SUCHASINTERLOCK,EMERGENCYSHUTDOWN,FAULTALARM,ETC2SYSTEMCOMPOSITIONANDTHEDESIGNOFCONTROLPROGRAM21PLCCONTROLSYSTEMINTHISSYSTEM,PLCTOCONTROLTHEOPERATIONOFTHEHOST,ATTHESAMETIMETOTHEONLINEDETECTIONANDCONTROLPARAMETERSSUCHASTIME,TEMPERATUREANDPRESSURETHEREFORE,ITSINPUTDEVICESINCLUDEMODESELECTIONSWITCH,BUTTON,CLOSETOTHECAMSWITCH,ROTARYENCODER,ETCOUTPUTDEVICESINCLUDEELECTROMAGNETICVALVECOILUNLOADING,ELECTROMAGNETICVALVE,ES1ANDES2EP1PRESSUREELECTROMAGNETICVALVE,PRESSURESOLENOIDVALVEEP2,ETC,CONTACTORANDALARMANDDISPLAYSIGNALINDICATORLIGHTS,ETCPOINTSOFCOMPREHENSIVEINPUT/OUTPUTDEVICES,THESYSTEMSELECTSTHEJAPANESEMITSUBISHIFX264MTTYPEPLC,BECAUSEBRICKMOLDINGMACHINENORMALLYWORKNIGHTANDDAYANDEVERYMINUTEOFWORKINGFREQUENCYISHIGHER,SOWECHOOSETHETRANSISTOROUTPUTTHISWAY,ATTHESAMETIME,THEFX2SERIESPLCHASSTRONGFUNCTION,THEUSERPROGRAMMEMORYCAPACITYISBIG,THECHARACTERISTICOFHIGHDEGREEOFINTELLIGENCE22CONTROLPROGRAMDESIGNBRICKMOLDINGMACHINEEACHWORKSTEPOFTHEPRODUCTIONPROCESSCONTROLPROGRAMBELONGSTOTHETYPICALSTEPPINGSEQUENCECONTROLPROGRAM,WECANUSEASTEPLADDERINSTRUCTIONSTLEASILYDRAWLADDERDIAGRAM,MANYONLINEPARAMETERDETECTIONANDCONTROLPROGRAMSSUCHASCRUSHINGFREQUENCY,TEMPERATURE,ETCPROGRAMISRELATIVELYDIFFICULT,INTHISPAPER,INORDERTOSUPPRESSTHENUMBEROFTIMESPERMINUTECOUNTSANDSUPPRESSTHECUMULATIVENUMBEROFCASESTOILLUSTRATETHEDESIGNOFTHISPROGRAM,WHENM8000TOONTHERISINGEDGEOFDIFFERENTIALOUTPUTMAKEM70ELECTRICALPULSESPLS,COUNTINGCFORREDUCTIONAPPROACHWHENM8000TOOFF,PLFMAKEM72ELECTRICPULSE,COUNTINGCFORADD,M8014ISSAID/POINTS0DATAREGISTERWILLBEC200COUNTERNUMBERMULTIPLIEDBY2THENDEPOSITEDINTHEC221,LADDERDIAGRAMX021SAID/ACTIVITIESINBEAMSTOPINPUTSIGNAL,ZEROY013SAID/MODELOCKED0OUTPUTSIGNAL,BRICKMOLDINGMACHINEEVERYLOCKDIE,C220ANUMBER,SOTHESUPPRESSIONARENATURALCUMULATIVENUMBERALSO,M103INTHELADDERDIAGRAMISUSEDTOSTARTTHEHIGHSPEEDCOUNTERC252SIGNALS,THEFIGUREDIDNOTDRAWTHEC252SPECIFICCONTROLPROCESSTHISSYSTEMIFDESERVETOGOUPAGAINTHEPCSUCHAS386PCS,EVERYMINUTECANBEREALIZEDTHEDYNAMICDISPLAYOFTHEPRODUCTQUANTITYANDCUMULATIVEPRODUCTION3ANTIJAMMINGANALYSISSINCEMOSTCERAMICSFACTORYWORKENVIRONMENTISRELATIVELYBAD,DUST,NOISE,ANDTHEPLCISWORKING24HCONTINUOUSLY,BRICKMOLDINGMACHINEPRESSINGTIMESPERMINUTEATAROUND17TIMES,SUCHAHIGHWORKFREQUENCY,PLCSLIGHTLYDISTURBED,ITWILLMAKETHEFACTORYSHUTDOWN,CAUSEGREATLOSSESACCORDINGLY,INTHEDESIGNOFTHISCONTROLSYSTEM,PLCANTIJAMMINGMEASURESISOURFOCUSONCONSIDERPROBLEM,DUETOTHEPLCOFTHEDRIVINGELEMENTMAINLYELECTROMAGNETICVALVEANDACCONTACTORCOIL,INORDERTOIMPROVETHERELIABILITYOFTHESYSTEM,WEINTHEPLCOUTPUTANDINCREASETHEPHOTOELECTRICISOLATIONBETWEENDRIVINGELEMENTZEROTYPESOLIDSTATERELAYACSSR,PLCTOAMPLIFYTHEOUTPUTCONTROLSIGNALBYTHETHYRISTORDRIVEACSSR,ACSSRAC220VVOLTAGEOUTPUTBYTHEDRIVINGELEMENTOFCONNECTIONS,MOVFORMETALOXIDEVARISTORINTHISDIAGRAM,ISUSEDTOPROTECTACSSR,BELOWTHENOMINALVALUEOFTHEVOLTAGE,THEVOLTAGEMOVRESISTANCEVALUEISLARGEWHENMORETHANNOMINALVALUE,THEVALUEISVERYSMALL,ATTHEINSTANTOFTHEVOLTAGEDISCONNECT,CANABSORBTHECOILSTORAGEENERGY,PRACTICEHASPROVEDTHATTHEANTIJAMMINGMEASURESAREVERYEFFECTIVE4CONCLUSIONFORDEBUGGINGTHESYSTEMAUTOMATICCONTROLOPERATION,FIRSTOFALL,SHOULDGUARANTEETHESINGLESTEPAFTERTHESUCCESSOFTHEPROGRAMDEBUGGING,AGAININTOWEEKLYANDCONTINUOUSCONTROL,ANDCOMMISSIONINGSHALLBECARRIEDOUTUNDERLOWPRESSURE,AFTERTHEABOVESTEPSARESET,THENCONNECTTHESYSTEMBOOSTERDUETOTHEPLCDEVELOPMENTFLEXIBILITY,FLEXIBLEANDEASYPROGRAMMINGANDCHANGEPARAMETERS,THEREFORE,BYADJUSTINGTHEPARAMETERSSUCHASTIME,TEMPERATURECANGETDIFFERENTPRESSINGCURVE,MEETTHENEEDSOFAVARIETYOFCERAMICTILEPRODUCTIONTECHNOLOGYTHISSYSTEMHASBEENRUNNINGFORMANYYEARS,AFTERWETRACKINGSURVEY,SYSTEMAUTOMATIONDEGREEISHIGH,ANTIJAMMINGISSTRONG,NOTONLYRAISEDTHELABORPRODUCTIVITY,ANDGREATLYREDUCETHELABORINTENSITY,GETTHEUSERSHIGHPRAISETHEMAJORGOALSOFFLOORTILEOFWALLOFPRODUCTIONENTERPRISEINOURCOUNTRYINTHENEARFUTUREWILLBETHEENTERPRISEINTOAVIRTUOUSCYCLETRACKOFMARKETECONOMYDEVELOPMENT,INCREASETHEENTERPRISEMARKETCOMPETITIVENESSOFPRODUCTS,MAKETHEENTERPRISEOBTAINGOODECONOMICBENEFIT,THEREFORE,ENTERPRISESMUSTDEVELOPOTHERGREATEFFORTNOTTOPRODUCEORMARKETIS