車輛制動裝置VehicleBrakingDevice任務六120型控制閥TYPE120CONTROLVALVEZHENGZHOURAILWAYVOCATIONAL&TECHNICALCOLLEGE主講人李西安SpeakerLiXi’an（四）緊急閥theemergencyvalve120型控制閥

TYPE120CONTROLVALVE六、緊急閥的作用是在緊急制動時加快制動管的排氣（緊急局減作用），使緊急制動的作用可靠，提高緊急制動靈敏度，從而提高緊急制動波速。Thefunctionoftheemergencyvalveistoacceleratetheexhaustofthebrakepipeduringemergencybraking(emergencylocalreductionfunction),ensuringreliableemergencybraking,improvingthesensitivityofemergencybrakingandthusincreasingthespeedofemergencybraking.緊急閥由緊急活塞組成、安定彈簧28、放風閥部、先導閥部以及緊急閥上蓋1、緊急閥下蓋18和緊急閥體10等零部件組成。Theemergencyvalveconsistsoftheemergencypiston,stabilizingspring28,exhaustvalvesection,pilotvalvesection,aswellastheuppercover1,lowercover18andbody10oftheemergencyvalve.120型控制閥

TYPE120CONTROLVALVE六、組裝后，緊急活塞膜板外邊緣被緊急閥上蓋壓緊在緊急閥體上，緊急活塞的上腔經暗道及安裝面上的通孔與中間體內的緊急室相通，緊急活塞的下腔通制動管。Afterassembly,theouteredgeoftheemergencypistondiaphragmplateispressedtightlyagainsttheuppercoveroftheemergencyvalvebody.Theupperchamberoftheemergencypistonisconnectedtotheemergencychamberintheintermediatebodythroughahiddenpassageandathrough-holeonthemountingsurface,whilethelowerchamber(stabilizingspringchamber)isconnectedtothebrakepipe.緊急閥就是利用緊急活塞上、下兩側的壓力差，控制先導閥、放風閥動作，產生緊急局減作用。Theemergencyvalveusesthepressuredifferencebetweentheemergencychamberandthebrakepipeontheupperandlowersidesoftheemergencypistontocontroltheoperationofthepilotvalveandtheexhaustvalve,generatingtheemergencylocalreductionfunction.緊急活塞桿頂面的異形密封圈稍突出于頂面。平時，在安定彈簧力的作用下，緊急活塞處于上部極端位置，此密封圈與緊急閥蓋密貼，緊急活塞桿的軸向孔與上腔被切斷，防止緊急室過充氣引起意外緊急制動。Thespecial-shapedsealringonthetopsurfaceoftheemergencypistonrodprotrudesslightly.Undernormalcircumstances,undertheactionofthestabilizingspringforce,theemergencypistonisintheupperextremeposition.Thesealringistightlyattachedtotheemergencyvalvecover,theaxialholeoftheemergencypistonrodisdisconnectedfromtheupperchamber,preventingover-inflationoftheemergencychamberfromcausingaccidentalemergencybraking.當列車管減壓，緊急活塞兩側產生壓力差，克服安定彈簧的彈力而下移時，緊急活塞桿頂面的軸向中心孔口開放。Whenthetrainpipeisdepressurized,thepressuredifferenceonbothsidesoftheemergencypistonovercomesthespringforceofthestabilizingspringandmovestheemergencypistondownward,openingthepilotvalveandtheexhaustvalve,generatingtheemergencylocalreductionfunction.120型控制閥

TYPE120CONTROLVALVE六、限孔三安定孔ThelimitingorificeⅢ(Diameter2.5mm)isstabilizingorifice.在緊急活塞桿的軸向中心孔內，控制緊急室壓力空氣向制動管逆流的速度，以保證緊急制動時在緊急活塞兩側形成足夠壓力差來推動緊急活塞下移，打開先導閥、放風閥，產生緊急局減作用；常用制動時，使緊急活塞兩側形成不了打開先導閥的壓力差。Itcontrolsthereverseflowspeedofcompressedairfromtheemergencychambertothebrakepipeduringemergencybrakingtoensurethatasufficientpressuredifferenceisformedonbothsidesoftheemergencypistontopushtheemergencypistondownward,openingthepilotvalveandtheexhaustvalveandgeneratingtheemergencylocalreductionfunction.Duringnormalbraking,thepressuredifferencerequiredforopeningthepilotvalvecannotbeformed.因此，限孔Ⅲ的直徑過大會降低緊急制動靈敏度，過小則會影響常用制動的安定性。Therefore,ifthediameterofthelimitingorificeⅢistoolarge,itwillreducethesensitivityofemergencybraking,whileifitistoosmall,itwillaffectthestabilityofnormalbraking.限孔四充氣限孔LimitingorificeⅣ(Diameter0.5mm)isinflationlimitingorifice.控制制動管向緊急室的充氣速度，防止緊急室充氣過快而引起以外緊急制動。Itcontrolstheinflationspeedofthebrakepipetotheemergencychamber,preventingrapidinflationoftheemergencychamberandcausingunintendedemergencybraking.限孔五排氣限孔LimitingorificeV(Diameter1.1mm)isexhaustlimitingorifice.在緊急活塞桿的下部，距下端13mm處的徑向小孔，緊急制動后，控制緊急室壓力空氣排人大氣的速度，使處于下部位置的緊急活塞在間隔一定的時間后才向上回移，保證施行緊急制動后的列車停車后，方可向制動管充氣，使列車緩解。Itisaradialsmallholelocated13mmabovethelowerendoftheemergencypistonrod.Afteremergencybraking,itcontrolsthespeedatwhichthecompressedairintheemergencychamberisreleasedintotheatmosphere,ensuringthattheemergencypiston,whichisinthelowerposition,onlyreturnsupwardafteracertainintervaloftime,allowingthetraintocometoastop.Onlyafterthat,thebrakepipecanbepressurizedtoreleasethebrakeandeasethetrain.a120型控制閥

TYPE120CONTROLVALVE六、b120型控制閥

TYPE120CONTROLVALVE六、放風閥部由等零部件組成。放風閥放風閥座放風閥導向桿放風閥彈簧O形密封圈先導閥部由等零部件組成。先導閥頂桿先導閥先導閥彈簧先導閥彈簧座

先導閥頂桿嵌裝在放風閥中心孔中。Thepilotvalvestemisfittedinthecentralholeoftheexhaustvalve.心軸下部球形外圓面與放風閥導向桿上腔的圓錐形內孔呈鉸式連接，保證放風閥與放風閥座密貼。Thelowersphericaloutersurfaceofthevalvestemishingedwiththeconicalinnerholeoftheexhaustvalveguiderodupperchamber,ensuringthetightfitbetweentheexhaustvalveandtheexhaustvalveseat.放風閥導向桿是一個套筒，下部外圓柱面作為上下移動的導向桿；中空部分形成上、下兩個空腔，兩空腔之間是先導閥座，先導閥座上方有4個直徑2毫米徑向孔經緊急閥排氣口通大氣。Theexhaustvalveguiderodisasleevewithalowercylindricalsurfacethatservesasaguidingrodforverticalmovement.Thehollowportionformstwochambers,oneaboveandonebelow,thepilotvalveseatislocatedbetweenthetwochambers.TherearefourDiameter2mmradialholesabovethepilotvalveseatthatallowatmosphericairtopassthroughtheemergencyvalveexhaustport.下腔內裝先導閥、先導閥彈簧，平時在先導閥彈簧作用下，先導閥與座密貼。Thelowerchambercontainsthepilotvalveandthepilotvalvespring,andundernormalconditions,thepilotvalveistightlyseatedontheseatduetotheactionofthepilotvalvespring.當先導閥被其頂桿頂開時，放風閥導向桿下腔內的制動管壓力空氣經這些小孔排向大氣。Whenthepilotvalveisopenedbyitsstem,thebrakepipecompressedairinthelowerchamberoftheexhaustvalveguiderodisexhaustedtotheatmospherethroughthesesmallholes.Theexhaustvalvesectionconsistsoftheexhaustvalveassembly26,exhaustvalveseat27,exhaustvalveguiderod25,exhaustvalvespring19andO-ringseal21(D28×3.1).Thepilotvalvesectionconsistsofthepilotvalvestem,pilotvalve,pilotvalvespringandpilotvalvespringseat.120型控制閥

TYPE120CONTROLVALVE六、放風閥導向桿下腔（包括先導閥彈簧室和放風閥室）經緊急閥與制動管相連通的暗道中。裝設直徑1毫米的縮孔四，當放風閥桿下腔的列車管壓力空氣經4個徑向孔排入大氣消除放風閥的背壓力后，限制制動管壓力空氣由于壓力差而充人放風閥桿下腔的速度，使放風閥桿下腔不能形成新的背壓，使緊急活塞比較容易地繼續下移打開放風閥，實現緊急局減作用，提高緊急制動的靈敏度。TheDiameter1.0mmreducedholeplug16(reducedholeplugⅥ),whichisinstalledintheconcealedpassageconnectingthelowercavityofthereleasevalveguiderod(includingthepilotvalvespringchamberandthereleasevalvechamber)throughtheemergencyvalveandthebrakepipe,playsaroleinlimitingthespeedatwhichthebrakepipe’spressureairentersthelowercavityofthereleasevalveguiderodduetothepressuredifference,afterthecompressedairfromthetrainpipepressureairenterstheatmospherethroughfourradialholestoeliminatethebackpressureofthereleasevalve.Thiseffectivelypreventsthelowercavityofthereleasevalveguiderodfromformingnewbackpressure,allowingtheemergencypistontocontinuetomovedownwardandopenthereleasevalve,thusachievingthedesiredemergencybrakingeffectandimprovingthesensitivityoftheemergencybrakingsystem.裝設直徑1毫米的縮孔四，當放風閥桿下腔的列車管壓力空氣經4個徑向孔排入大氣消除放風閥的背壓力后，限制制動管壓力空氣由于壓力差而充人放風閥桿下腔的速度，使放風閥桿下腔不能形成新的背壓，使緊急活塞比較容易地繼續下移打開放風閥，實現緊急局減作用，提高緊急制動的靈敏度。Theemergencyvalvebodyismadeofcastiron,thesmallcircularholeonthemountingsurfaceisconnectedtotheemergencychamber,whilethelargecircularholeisconnectedtothebrakepipe.A30-meshdustscreen13isinstalledonthebrakepipepassagetoremovedustandotherimpuritiesfromthecompressedairenteringtheemer