2014年電大液壓氣動技術(shù)基礎(chǔ)期末復(fù)習(xí)題及答案參考小抄【電大考試必備】

電大液壓氣動技術(shù)基礎(chǔ)期末復(fù)習(xí)題及答案參考小抄一、填空1．液壓系統(tǒng)中的兩個重要參數(shù)是(流量)和(壓力)，液壓傳動是以液體的(壓力)能傳遞動力的。2．根據(jù)度量基準的不同，液體的壓力分為(相對壓力)和(絕對壓力)兩種，大多數(shù)表測得的壓力是(相對壓力)。3．調(diào)速閥是由(定差減壓)閥和節(jié)流閥(串聯(lián))連接而組成。4．容積調(diào)速基本回路有三種，它們是(變量泵-定量馬達)、(變量泵-變量馬達)及(復(fù)合調(diào)速)。5．差動回路可以實現(xiàn)油缸的(快速)運動，但差動連接時，油缸的推力卻明顯的(降低)。二、選擇題1．運動速度（B）時宜采用粘度較低的液壓油減少摩擦損失：工作壓力（）時宜采用粘度較高的液壓油以減少泄漏。A.高低B.高高C.低高D.低低2.在用一個泵驅(qū)動一個執(zhí)行元件的液壓系統(tǒng)中，采用三位四通換向閥使泵卸荷，應(yīng)選用（D）型中位機能A.“P”型B.“O”型C.“Y”型D.“H”型3．限制齒輪泵工作壓力提高的主要因素是(C)。(A)存在困油現(xiàn)象(B)流量脈動(C)泄漏(D)徑向力不平衡溢流閥的控制油壓來自閥的(A)(A)進口端(B)出口端(C)設(shè)有單獨的泄油油路(D)沒有單獨的泄油油路5調(diào)速閥是用（B）而成的A.節(jié)流閥和順序閥串聯(lián)B.節(jié)流閥和定差減壓閥串聯(lián)C.節(jié)流閥和順序閥并聯(lián)D.節(jié)流閥和定差減壓閥并聯(lián)三、簡答題1.液壓傳動系統(tǒng)由哪幾部分組成部分?各組成部分的作用是什么?（答：液壓傳動系統(tǒng)主要有以下五部分組成：動力元件：液壓泵，其功能是將原動機輸入的機械能轉(zhuǎn)換成液體的壓力能，為系統(tǒng)提供動力。執(zhí)行元件：液壓缸、液壓馬達，它們的功能是將流體的壓力能轉(zhuǎn)換成機械能，輸出力和速度（或轉(zhuǎn)矩和轉(zhuǎn)速），以帶動負載進行直線運動或旋轉(zhuǎn)運動?？刂圃簤毫?、流量和方向控制閥，它們的作用是控制和調(diào)節(jié)系統(tǒng)中液體的壓力、流量和流動方向，以保證執(zhí)行元件達到所要求的輸出力（或力矩）、運動速度和運動方向。輔助元件：保證系統(tǒng)正常工作所需要的輔助裝置，包括管道、管接頭、油箱、過濾器和壓力計等。工作介質(zhì)：用以傳遞動力并起潤滑作用。2．簡述液壓沖擊產(chǎn)生的原因。在液壓系統(tǒng)中，由于某種原因，液體壓力在一瞬間會突然升高，產(chǎn)生很高的壓力峰值，這種現(xiàn)象稱為液壓沖擊。液壓沖擊產(chǎn)生的原因：（1）液流通道迅速關(guān)閉或液流迅速換向使液流速度的大小或方向突然變化時，由于液流的慣力引起的液壓沖擊。（2）運動著的工作部件突然制動或換向時，因工作部件的慣性引起的液壓沖擊。（3）某些液壓元件動作失靈或不靈敏，使系統(tǒng)壓力升高而引起的液壓沖擊。3．何謂氣穴現(xiàn)象？它有哪些危害？通常采取哪些措施防止氣穴及氣蝕？在液壓系統(tǒng)中（或液壓元件中）因局部壓力降低而有氣泡形成的現(xiàn)象稱為氣穴現(xiàn)象。危害：引起氣蝕，產(chǎn)生振動噪聲；形成氣塞破壞系統(tǒng)正常工作。措施：盡力減少油液中空氣的含量，防止氣體混入系統(tǒng)；防止系統(tǒng)局部壓力過低；在易發(fā)生氣穴部位采用耐蝕材料及保護鍍層。4.說明下圖所示雙泵雙速回路的工作原理，并分析確定閥3、4的調(diào)定壓力關(guān)系？（1）快速時：低壓大流量泵2、高壓小流量泵1同時向系統(tǒng)供油；慢速時：高壓小流量1向系統(tǒng)供油，低壓大流量泵2卸荷（2）閥3的調(diào)定壓力大于閥4的調(diào)定壓力四、分析題1.若把先導(dǎo)式溢流閥的遠控制口當成泄漏口接油箱，試分析液壓系統(tǒng)會產(chǎn)生什么問題產(chǎn)生卸荷現(xiàn)象，系統(tǒng)壓力近乎零。2．夾緊回路如下圖所示，若溢流閥的調(diào)整壓力p1＝3Mpa、減壓閥的調(diào)整壓力p2＝2Mpa。（1）試分析活塞空載運動時A、B兩點的壓力各為多少？減壓閥的閥芯處于什么狀態(tài)？（2）工件夾緊，活塞停止運動后，A、B兩點的壓力又各為多少？此時，減壓閥芯又處于什么狀態(tài)？答：（1）活塞空載運動，由于沒有負載力作用，系統(tǒng)工作壓力為0，不考慮沿程阻力損失，A、B兩點壓力相等，都是0MPa，此時減壓閥處在非工作狀態(tài)，閥口常開（2）工件夾緊后，溢流閥工作，此時A點壓力為溢流閥調(diào)定壓力，3MPa，減壓閥也開始工作，B點壓力為2MPa，減壓閥閥芯處于半開狀態(tài)，保證出口壓力恒定在2MPa。五、計算題1．圖示的簡化回路中，溢流閥的調(diào)定壓力是2.5×106Pa,系統(tǒng)工作時溢流閥始終有油流回油箱，活塞有效工作面積為0.1m2,求當負載分別為：F=2×104N；F=0；F=-5×103N時，油缸出口壓力P2各為多工進+--快退-+-請您刪除一下內(nèi)容，O(∩_∩)O謝謝?。?！【China's10must-seeanimations】TheChineseanimationindustryhasseenconsiderablegrowthinthelastseveralyears.Itwentthroughagoldenageinthelate1970sand1980swhensuccessivelybrilliantanimationworkwasproduced.Hereare10must-seeclassicsfromChina'sanimationoutpouringthatarenottobemissed.Let'srecallthesecolorfulimagesthatbroughtthecountrygreatjoy.CalabashBrothersCalabashBrothers(Chinese:葫蘆娃)isaChineseanimationTVseriesproducedby

Shanghai

Animation

Film

Studio.Inthe1980stheserieswasoneofthemostpopularanimationsinChina.ItwasreleasedatapointwhentheChineseanimationindustrywasinarelativelydownedstatecomparedtotherestoftheinternationalcommunity.Still,theserieswastranslatedinto7differentlanguages.Theepisodeswereproducedwithavastamountofpaper-cutanimations.BlackCatDetectiveBlackCatDetective(Chinese:黑貓警長)isaChineseanimationtelevisionseriesproducedbytheShanghaiAnimationFilmStudio.ItissometimesknownasMr.Black.Theserieswasoriginallyairedfrom1984to1987.InJune2006,arebroadcastingoftheoriginalserieswasannounced.Criticsbemoantheseries'violence,andlackofsuitabilityforchildren'seducation.Proponentsoftheshowclaimthatitismerelyforentertainment.Effendi"Effendi",meaningsirand

teacherinTurkish,istherespectfulnameforpeoplewhoownwisdomandknowledge.Thehero'srealnamewasNasreddin.Hewaswiseandwittyand,moreimportantly,hehadthecouragetoresisttheexploitationofnoblemen.Hewasalsofullofcompassionandtriedhisbesttohelppoorpeople.AdventureofShukeandBeita【舒克與貝塔】AdventureofShukeandBeita(Chinese:舒克和貝塔)isaclassicanimationbyZhengYuanjie,whoisknownasKingofFairyTalesinChina.ShukeandBeitaaretwomicewhodon'twanttostealfoodlikeothermice.ShukebecameapilotandBeitabecameatankdriver,andthepairmetaccidentallyandbecamegoodfriends.ThentheybefriendedaboynamedPipilu.WiththehelpofPiPilu,theyco-foundedanairlinenamedShukeBeitaAirlinestohelpotheranimals.Althoughthereareonly13episodesinthisseries,thecontentisverycompactandattractive.Theanimationshowsthepreciousnessoffriendshipandhowpeopleshouldbebravewhenfacingdifficulties.Evenadultsrecallingthisanimationtodaycanstillfeeltouchedbysomescenes.SecretsoftheHeavenlyBookSecretsoftheHeavenlyBook,(Chinese:天書奇談)

alsoreferredtoas"LegendoftheSealedBook"or"TalesabouttheHeavenlyBook",wasreleasedin1983.Thefilmwasproducedwithrigorousdubbingandfluidcombinationofmusicandvividanimations.Thestoryisbasedontheclassicliterature"PingYaoZhuan",meaning"TheSuppressionoftheDemons"byFengMenglong.Yuangong,thedeacon,openedtheshrineandexposedtheholybooktothehumanworld.Hecarvedthebook'scontentsonthestonewallofawhitecloudcaveinthemountains.Hewasthenpunishedwithguardingthebookforlifebythejadeemperorforbreakingheaven'slaw.Inordertopassthisholybooktohumanbeings,hewouldhavetogetbytheantagonistfox.ThewholeanimationischaracterizedbycharmingChinese

painting,includingpavilions,ancientarchitecture,ripplingstreamsandcrowdedmarkets,whichfullydemonstratetheuniquebeautyofChina'snaturalscenery.PleasantGoatandBigBigWolf【喜洋洋與灰太狼】PleasantGoatandBigBigWolf(Chinese:喜羊羊與灰太狼)isaChineseanimatedtelevisionseries.TheshowisaboutagroupofgoatslivingontheGreenPasture,andthestoryrevolvesaroundaclumsywolfwhowantstoeatthem.Itisapopulardomesticanimationseriesandhasbeenadaptedinto

movies.NezhaConquerstheDragonKing（Chinese:哪吒鬧海）

isanoutstandinganimationissuedbytheMinistryofCulturein1979andisbasedonanepisodefromtheChinesemythologicalnovel"FengshenYanyi".Amothergavebirthtoaballoffleshshapedlikealotusbud.Thefather,LiJing,choppedopentheball,andbeautifulboy,Nezha,sprungout.Oneday,whenNezhawassevenyearsold,hewenttothenearbyseashoreforaswimandkilledthethirdsonoftheDragonKingwhowaspersecutinglocalresidents.ThestoryprimarilyrevolvesaroundtheDragonKing'sfeudwithNezhaoverhisson'sdeath.Throughbraveryandwit,Nezhafinallybrokeintotheunderwaterpalaceandsuccessfullydefeatedhim.ThefilmshowsvariouskindsofattractivesceneriesandthetraditionalcultureofChina,suchasspectacularmountains,elegantseawavesandexquisiteancientChineseclothes.Ithasreceivedavarietyofawards.HavocinHeavenThestoryofHavocinHeaven（Chinese:大鬧天宮）isbasedontheearliestchaptersoftheclassicstory

JourneytotheWest.ThemaincharacterisSunWukong,akatheMonkeyKing,whorebelsagainsttheJadeEmperorofheaven.Thestylizedanimationanddrumsandpercussionaccompanimentusedinthisfilmareheavilyinfluencedby

Beijing

Operatraditions.ThenameofthemoviebecameacolloquialismintheChineselanguagetodescribesomeonemakingamess.Regardlessthatitwasananimatedfilm,itstillbecameoneofthemostinfluentialfilmsinallofAsia.CountlesscartoonadaptationsthatfollowedhavereusedthesameclassicstoryJourneytotheWest,yetmanyconsiderthis1964iterationtobethemostoriginal,fittingandmemorable,TheGoldenMonkeyDefeatsaDemon【金猴降妖】TheGoldenMonkeyDefeatsaDemon(Chinese:金猴降妖),alsoreferredas"TheMonkeyKingConquerstheDemon",isadaptedfromchaptersoftheChineseclassics"JourneytotheWest,"or"Monkey"intheWesternworld.Thefive-episodeanimationseriestellsthestoryofMonkeyKingSunWukong,whofollowedMonkXuanZang'striptotheWesttotaketheBuddhisticsutra.Theymetawhiteboneevil,andtheeviltransformedhumanappearancesthreetimestoseducethemonk.TwiceMonkeyKingrecognizeditandbroughtitdown.ThemonkwasunabletorecognizethemonsterandexpelledSunWukong.XuanZangwasthencapturedbythemonster.FortunatelyBajie