Brush,high,temperature,oxide,film,generally,at,about,70,DEG,C,is,easy,to,form,,when,the,collector,ring,,brush,overheat,fault,,usually,temperature,over,150,DEG,C,,and,even,change,the,new,brush,,oxide,film,is,not,easy,to,form,,can,not,play,a,role,in,lubrication,,brush,wear,will,increase,,resulting,in,temperature,continue,to,rise,,become,a,vicious,spiral.,This,may,take,the,external,forced,cooling,methods,,such,as,smearing,Vaseline,,high-power,fan,ventilation,and,other,means,,so,that,the,collector,ring,temperature,dropped,to,the,normal,range,,over,a,period,of,time,,let,the,brush,surface,oxide,film,is,formed,gradually,,make,enter,benign,loop,state.详情见, ,换向器