车辆制动装置Vehicle Braking Device

车辆制动装置VehicleBrakingDevice任务六120型控制阀TYPE120CONTROLVALVEZHENGZHOURAILWAYVOCATIONAL&TECHNICALCOLLEGE主讲人李西安SpeakerLiXi’an（四）紧急阀theemergencyvalve120型控制阀

TYPE120CONTROLVALVE六、紧急阀的作用是在紧急制动时加快制动管的排气（紧急局减作用），使紧急制动的作用可靠，提高紧急制动灵敏度，从而提高紧急制动波速。Thefunctionoftheemergencyvalveistoacceleratetheexhaustofthebrakepipeduringemergencybraking(emergencylocalreductionfunction),ensuringreliableemergencybraking,improvingthesensitivityofemergencybrakingandthusincreasingthespeedofemergencybraking.紧急阀由紧急活塞组成、安定弹簧28、放风阀部、先导阀部以及紧急阀上盖1、紧急阀下盖18和紧急阀体10等零部件组成。Theemergencyvalveconsistsoftheemergencypiston,stabilizingspring28,exhaustvalvesection,pilotvalvesection,aswellastheuppercover1,lowercover18andbody10oftheemergencyvalve.120型控制阀

TYPE120CONTROLVALVE六、组装后，紧急活塞膜板外边缘被紧急阀上盖压紧在紧急阀体上，紧急活塞的上腔经暗道及安装面上的通孔与中间体内的紧急室相通，紧急活塞的下腔通制动管。Afterassembly,theouteredgeoftheemergencypistondiaphragmplateispressedtightlyagainsttheuppercoveroftheemergencyvalvebody.Theupperchamberoftheemergencypistonisconnectedtotheemergencychamberintheintermediatebodythroughahiddenpassageandathrough-holeonthemountingsurface,whilethelowerchamber(stabilizingspringchamber)isconnectedtothebrakepipe.紧急阀就是利用紧急活塞上、下两侧的压力差，控制先导阀、放风阀动作，产生紧急局减作用。Theemergencyvalveusesthepressuredifferencebetweentheemergencychamberandthebrakepipeontheupperandlowersidesoftheemergencypistontocontroltheoperationofthepilotvalveandtheexhaustvalve,generatingtheemergencylocalreductionfunction.紧急活塞杆顶面的异形密封圈稍突出于顶面。平时，在安定弹簧力的作用下，紧急活塞处于上部极端位置，此密封圈与紧急阀盖密贴，紧急活塞杆的轴向孔与上腔被切断，防止紧急室过充气引起意外紧急制动。Thespecial-shapedsealringonthetopsurfaceoftheemergencypistonrodprotrudesslightly.Undernormalcircumstances,undertheactionofthestabilizingspringforce,theemergencypistonisintheupperextremeposition.Thesealringistightlyattachedtotheemergencyvalvecover,theaxialholeoftheemergencypistonrodisdisconnectedfromtheupperchamber,preventingover-inflationoftheemergencychamberfromcausingaccidentalemergencybraking.当列车管减压，紧急活塞两侧产生压力差，克服安定弹簧的弹力而下移时，紧急活塞杆顶面的轴向中心孔口开放。Whenthetrainpipeisdepressurized,thepressuredifferenceonbothsidesoftheemergencypistonovercomesthespringforceofthestabilizingspringandmovestheemergencypistondownward,openingthepilotvalveandtheexhaustvalve,generatingtheemergencylocalreductionfunction.120型控制阀

TYPE120CONTROLVALVE六、限孔三安定孔ThelimitingorificeⅢ(Diameter2.5mm)isstabilizingorifice.在紧急活塞杆的轴向中心孔内，控制紧急室压力空气向制动管逆流的速度，以保证紧急制动时在紧急活塞两侧形成足够压力差来推动紧急活塞下移，打开先导阀、放风阀，产生紧急局减作用；常用制动时，使紧急活塞两侧形成不了打开先导阀的压力差。Itcontrolsthereverseflowspeedofcompressedairfromtheemergencychambertothebrakepipeduringemergencybrakingtoensurethatasufficientpressuredifferenceisformedonbothsidesoftheemergencypistontopushtheemergencypistondownward,openingthepilotvalveandtheexhaustvalveandgeneratingtheemergencylocalreductionfunction.Duringnormalbraking,thepressuredifferencerequiredforopeningthepilotvalvecannotbeformed.因此，限孔Ⅲ的直径过大会降低紧急制动灵敏度，过小则会影响常用制动的安定性。Therefore,ifthediameterofthelimitingorificeⅢistoolarge,itwillreducethesensitivityofemergencybraking,whileifitistoosmall,itwillaffectthestabilityofnormalbraking.限孔四充气限孔LimitingorificeⅣ(Diameter0.5mm)isinflationlimitingorifice.控制制动管向紧急室的充气速度，防止紧急室充气过快而引起以外紧急制动。Itcontrolstheinflationspeedofthebrakepipetotheemergencychamber,preventingrapidinflationoftheemergencychamberandcausingunintendedemergencybraking.限孔五排气限孔LimitingorificeV(Diameter1.1mm)isexhaustlimitingorifice.在紧急活塞杆的下部，距下端13mm处的径向小孔，紧急制动后，控制紧急室压力空气排人大气的速度，使处于下部位置的紧急活塞在间隔一定的时间后才向上回移，保证施行紧急制动后的列车停车后，方可向制动管充气，使列车缓解。Itisaradialsmallholelocated13mmabovethelowerendoftheemergencypistonrod.Afteremergencybraking,itcontrolsthespeedatwhichthecompressedairintheemergencychamberisreleasedintotheatmosphere,ensuringthattheemergencypiston,whichisinthelowerposition,onlyreturnsupwardafteracertainintervaloftime,allowingthetraintocometoastop.Onlyafterthat,thebrakepipecanbepressurizedtoreleasethebrakeandeasethetrain.a120型控制阀

TYPE120CONTROLVALVE六、b120型控制阀

TYPE120CONTROLVALVE六、放风阀部由等零部件组成。放风阀放风阀座放风阀导向杆放风阀弹簧O形密封圈先导阀部由等零部件组成。先导阀顶杆先导阀先导阀弹簧先导阀弹簧座

先导阀顶杆嵌装在放风阀中心孔中。Thepilotvalvestemisfittedinthecentralholeoftheexhaustvalve.心轴下部球形外圆面与放风阀导向杆上腔的圆锥形内孔呈铰式连接，保证放风阀与放风阀座密贴。Thelowersphericaloutersurfaceofthevalvestemishingedwiththeconicalinnerholeoftheexhaustvalveguiderodupperchamber,ensuringthetightfitbetweentheexhaustvalveandtheexhaustvalveseat.放风阀导向杆是一个套筒，下部外圆柱面作为上下移动的导向杆；中空部分形成上、下两个空腔，两空腔之间是先导阀座，先导阀座上方有4个直径2毫米径向孔经紧急阀排气口通大气。Theexhaustvalveguiderodisasleevewithalowercylindricalsurfacethatservesasaguidingrodforverticalmovement.Thehollowportionformstwochambers,oneaboveandonebelow,thepilotvalveseatislocatedbetweenthetwochambers.TherearefourDiameter2mmradialholesabovethepilotvalveseatthatallowatmosphericairtopassthroughtheemergencyvalveexhaustport.下腔内装先导阀、先导阀弹簧，平时在先导阀弹簧作用下，先导阀与座密贴。Thelowerchambercontainsthepilotvalveandthepilotvalvespring,andundernormalconditions,thepilotvalveistightlyseatedontheseatduetotheactionofthepilotvalvespring.当先导阀被其顶杆顶开时，放风阀导向杆下腔内的制动管压力空气经这些小孔排向大气。Whenthepilotvalveisopenedbyitsstem,thebrakepipecompressedairinthelowerchamberoftheexhaustvalveguiderodisexhaustedtotheatmospherethroughthesesmallholes.Theexhaustvalvesectionconsistsoftheexhaustvalveassembly26,exhaustvalveseat27,exhaustvalveguiderod25,exhaustvalvespring19andO-ringseal21(D28×3.1).Thepilotvalvesectionconsistsofthepilotvalvestem,pilotvalve,pilotvalvespringandpilotvalvespringseat.120型控制阀

TYPE120CONTROLVALVE六、放风阀导向杆下腔（包括先导阀弹簧室和放风阀室）经紧急阀与制动管相连通的暗道中。装设直径1毫米的缩孔四，当放风阀杆下腔的列车管压力空气经4个径向孔排入大气消除放风阀的背压力后，限制制动管压力空气由于压力差而充人放风阀杆下腔的速度，使放风阀杆下腔不能形成新的背压，使紧急活塞比较容易地继续下移打开放风阀，实现紧急局减作用，提高紧急制动的灵敏度。TheDiameter1.0mmreducedholeplug16(reducedholeplugⅥ),whichisinstalledintheconcealedpassageconnectingthelowercavityofthereleasevalveguiderod(includingthepilotvalvespringchamberandthereleasevalvechamber)throughtheemergencyvalveandthebrakepipe,playsaroleinlimitingthespeedatwhichthebrakepipe’spressureairentersthelowercavityofthereleasevalveguiderodduetothepressuredifference,afterthecompressedairfromthetrainpipepressureairenterstheatmospherethroughfourradialholestoeliminatethebackpressureofthereleasevalve.Thiseffectivelypreventsthelowercavityofthereleasevalveguiderodfromformingnewbackpressure,allowingtheemergencypistontocontinuetomovedownwardandopenthereleasevalve,thusachievingthedesiredemergencybrakingeffectandimprovingthesensitivityoftheemergencybrakingsystem.装设直径1毫米的缩孔四，当放风阀杆下腔的列车管压力空气经4个径向孔排入大气消除放风阀的背压力后，限制制动管压力空气由于压力差而充人放风阀杆下腔的速度，使放风阀杆下腔不能形成新的背压，使紧急活塞比较容易地继续下移打开放风阀，实现紧急局减作用，提高紧急制动的灵敏度。Theemergencyvalvebodyismadeofcastiron,thesmallcircularholeonthemountingsurfaceisconnectedtotheemergencychamber,whilethelargecircularholeisconnectedtothebrakepipe.A30-meshdustscreen13isinstalledonthebrakepipepassagetoremovedustandotherimpuritiesfromthecompressedairenteringtheemer