机床线路常见故障的排故 学习指导用书

机床线路排故实习指导书杭州职业技术学院机电工程系电气教研室2006年10月编机床线路排故实习指导书2目录课题一：机床电气控制电路的故障分析方法··································································································3一、如何阅读机床电气原理图·······················································································3二、机床电气控制电路故障的一般分析方法·····································································3三、机床电气控制电路电阻法检查故障举例·····································································5附件一智能答题器的操作方法·················································································8课题二：X62W万能铣床故障的分析与排除·································································································10第一节X62W型卧式万能铣库电气控制线路分析······························································13一、铣床的主要工作情况···························································································13二、主电路·············································································································13三、控制电路··········································································································14YL-ZX型X62W万能铣床电路故障点原理图··································································19第二节X62W万能铣床故障的分析与排除·······································································20一、X62万能铣床面板······························································································20二、X62万能铣床故障分析························································································20四、X62W铣床电路问答题························································································27附件二YL-ZX型X62W万能铣床电路实训考核台故障现象············································32课题三：T68镗床故障的分析与排除············································································································33第一节T68型镗床电气控制线路分析·············································································36一、T68型卧式镗床的主要工作情况············································································36二、主电路·············································································································36三、控制线路··········································································································37五、辅助电路分析····································································································39YL-ZT型T68镗床电路故障点原理图···········································································40第二节T68镗床故障的分析与排除················································································41一、T68镗床的面板·································································································41二、T6T镗床故障分析······························································································41三、T68型镗床电路问答题························································································47附件三YL-ZT型T68镗床电路实训考核台故障现象····················································49课题四：Z3050摇臂钻床故障的分析与排除································································································50第一节Z3050摇臂钻床电气控制线路分析······································································53一、主要结构及运动形式···························································································53二、摇臂钻床的电力拖动特点及控制要求······································································53三．电气控制线路分析······························································································54YL-ZT型T68摇臂钻床电路故障点原理图·····································································57第二节电气线路常见故障分析······················································································58附件四YL-ZZ型Z3050摇臂钻床电路实训考核台故障现象···········································60机床线路排故实习指导书3课题一：机床电气控制电路的故障分析方法由于各类机床型号不止一种，即使同一种型号，制造商的不同，其控制电路也存在差别。只有通过典型的机床控制电路的学习，进行归纳推敲，才能抓住各类机床的特殊性与普遍性。重点学会阅读、分析机床电气控制电路的原理图；学会常见故障的分析方法以及维修技能，关键是能做到举一反三，触类旁通。检修机床电路是一项技能性很强而又细致的工作。当机床在运行时一旦发生故障，检修人员首先对其进行认真的检查，经过周密的思考，作出正确的判断，找出故障源，然后着手排除故障。一、如何阅读机床电气原理图掌握了阅读原理图的方法和技巧，对于分析电气电路，排除机床电路故障是十分有意义的。机床电气原理图一般由主电路、控制电路、照明电路、指示电路等几部分组成。阅读方法如下：1、主电路的分析：阅读主电路时，关键是先了解主电路中有哪些用电设备，主要所起的作用，由哪些电器来控制，采取哪些保护措施。2、控制电路的分析：阅读控制电路时，根据主电路中接触器的主触点编号，很快找到相应的线圈以及控制电路。依次分析出电路的控制功能。从简单到复杂，从局部到整体，最后综合起来分析，就可以全面读懂控制电路。3、照明电路的分析：阅读照明电路时，查看变压器的变比、灯泡的额定电压。4、指示电路的分析：阅读指示电路时，了解这部分的内容，很重要的一点是：当电路正常工作时，为机床正常工作状态的指示；当机床出现故障时，是机床故障信息反馈的依据。二、机床电气控制电路故障的一般分析方法1、修理前的调查研究A、问询问机床操作人员，故障发生前后的情况如何，有利于根据电气设备的工作原理来判断发生故障的部位，分析出故障的原因。B、看观察熔断器内的熔体是否熔断；其它电气元件有烧毁、发热、断线、导线连接螺钉是否松动；触机床线路排故实习指导书4点是否氧化、积尘等。要特别注意高电压、大电流的地方，活动机会多的部位，容易受潮的接插件等。C、听电动机、变压器、接触器等，正常运行的声音和发生故障时的声音是有区别的，听声音是否正常，可以帮助寻找故障的范围、部位。D、摸电动机、电磁线圈、变压器等发生故障时，温度会显著上升，可切断电源后用手去触摸判断元件是否正常。注：不论电路通电还是断电，要特别注意不能用手直接去触摸金属触点！必需借助仪表来测量。2、从机床电气原理图进行分析首先熟悉机床的电气控制电路，结合故障现象，对电路工作原理进行分析，便可以迅速判断出故障发生的可能范围。3、检查方法根据故障现象分析，先弄清属于主电路的故障还是控制电路的故障，属于电动机的故障还是控制设备的故障。当故障确认以后，应该进一步检查电动机或控制设备。必要时可采用替代法，即用好的电动机或用电设备来替代。属于控制电路的，应该先进行一般的外观检查，检查控制电路的相关电气元件。如接触器、继电器、熔断器等有无硬裂、烧痕、接线脱落、熔体是否熔断等，同时用万用表检查线圈有无断线、烧毁，触点是否熔焊。外观检查找不到故障时，将电动机从电路中卸下，对控制电路逐步检查，可以进行通电吸合试验，观察机床电气各电器元件是否按要求顺序动作，发现哪部分动作有问题，就在那部分找故障点，逐步缩小故障范围，直到全部