第一篇:漢語(yǔ)翻譯第九講簡(jiǎn)單句變復(fù)合句[范文]
漢語(yǔ)翻譯第九講
漢語(yǔ)翻譯技巧簡(jiǎn)單句變復(fù)合句
一、練習(xí)討論和講評(píng)
本來(lái),生命只有一次,對(duì)于誰(shuí)都是寶貴的。但是,假使他的生命溶化在大眾的事業(yè)里面,假使他天天在為這世界干事業(yè)是不死的,他會(huì)領(lǐng)略到“永久的年輕”的感覺。而“浮生如夢(mèng)”的人,從這個(gè)世界拿去的很多,而給這世界的卻很少——他總有一天會(huì)覺得疲乏得快要死亡:他連拿都沒(méi)有力量了。衰老和無(wú)能的悲哀,像鉛一樣沉重,壓在他的心頭。青春是多么短啊。
One has but one life to live and, naturally, it is treasured by all.However, if one is dedicated to the cause of the people, if he does something every day for the world, he is living and, though eventually he will die, the cause he lives for—the cause of the people will never die.In other words, he will gain a sense of “eternal youth” As for the one who lives his life like a floating cloud;he takes a lot from the world but gives little in return.Sooner or later he will be approaching death with such tiredness that he will find himself deprived of the energy to “take”.Then the grief caused by age and impotence will make him feel as if a heavy load of lead was in the mind.How fast youth goes!他總有一天會(huì)覺得疲乏得快要死亡。Sooner or later he will be exhausted to death.他總有一天會(huì)覺得疲非常疲乏。然而“他總有一天會(huì)覺得疲乏得快要死亡。”的意義是:他總有一天會(huì)覺得疲乏,感到快要死亡了。Sooner or later he will be approaching death with such tiredness.Sooner or later he will be exhausted,having the sense that he will be approaching death.1.He was thirsty to death.He was extremely thirsty.2.He was stabbed to death.He died because he was stabbed.He was beaten to death.二、簡(jiǎn)單句變復(fù)合句
有時(shí)為了使英語(yǔ)句子的連貫性更強(qiáng), 表達(dá)也更為貼切、自然、優(yōu)美,我們將兩個(gè)或者多個(gè)簡(jiǎn)單漢語(yǔ)句翻譯成一個(gè)英語(yǔ)句子。英語(yǔ)句子之間加上and, but, or(或者, 否則), for(因?yàn)?, while(而, 卻), when(就在這個(gè)時(shí)候), not only...but also等并列連詞, 使其成為并列復(fù)合句。如:
(1)我們戶外活動(dòng)需要三個(gè)小時(shí),大概11點(diǎn)回來(lái),校門一帶關(guān)了。⑴ Our outdoor activity will last three hours.We’ll be back at about 11 o’clock.The school gate must be closed.→Our outdoor activity will last three hours and the school gate must be closedwhen we’ll be back at about 11 o’clock.⑵飛機(jī)七點(diǎn)起飛,趕快,要不趕不上飛機(jī)了。
⑵ The plane takes off at seven.You must hurry.You’ll miss the plane.→You must hurry or you’ll miss the plane which takes off at seven.⑶蜜糖甜蜜蜜,蜜蜂很刺人。
⑶Honey is sweet.The bee stings.→Honey is sweet but the bee stings.在兩個(gè)或者多個(gè)簡(jiǎn)單句之間加上when, after, as, because, where, which, who等從屬連詞, 可以使簡(jiǎn)單句變成復(fù)合句。如:
(4)英語(yǔ)俱樂(lè)部可以組織各種活動(dòng),我們?cè)诨顒?dòng)中不但可以練習(xí)英語(yǔ)還可以學(xué)習(xí)更多英語(yǔ)。
(4)We will organize all kinds of activities in our English club.We can not only practise but also learn more English in the activities.(改為含定語(yǔ)從句的復(fù)合句)→We will organize all kinds of activities in our English club in which we can not only practise but also learn more English.(5)沒(méi)有趕上頭班車,他上學(xué)遲到了。
(5)He missed the first bus.He came to school late.(改為含狀語(yǔ)從句的復(fù)合句)→Because he missed the first bus, he came to school late.→He missed the first bus, so he came to school late.即時(shí)練習(xí)將下列各組句子合并成并列復(fù)合句或主從復(fù)合句。(6),19世紀(jì)末,有一個(gè)聞名遐邇的偵探,名叫Sherlock Holmes,家住倫敦。
⑴ There was once a famous detective.⑵ He was named Sherlock Holmes.⑶ He lived in London.⑷ The time was at the end of the nineteenth century.---------There was once a famous detective named Sherlock who lived in London at the end of the nineteenth century.(7).根據(jù)調(diào)查,79.3%的居民反映說(shuō),他們的主要目的是幫助父母親生活得更好,67.7%說(shuō),他們努力工作是為了改變自己的命運(yùn)。(7)⑴ 79.3% of the surveyed citizens say that their main motivation is to help their parents to live a better life.⑵ 67.7% claim that they work hard in order to change their own fate.---------79.3% of the surveyed netizens say that their main motivation is to help their parents to live a better life while 67.7% claim that they work hard in order to change their own fate.(8)知識(shí)就是力量,我們是大學(xué)生,必須努力學(xué)習(xí)。Knowledge is power.We are college students.We must study hard.-------We, who are college student, must study hard because knowledge is power.(9.)寫作方法各種各樣,同學(xué)們可以用這一種方法提供寫作努力,增加自信力。
⑴There are ways and ways to improve writing ability
(2)Students can improve their writing ability in this way.(3)They can strengthen their self-confidence.--------.Though There are ways and ways to improve writing ability , students can improve their writing ability in this way to increase their self-confidence.(10)這是上海最雄偉的大樓,許多外國(guó)專家在此住居。
1.This is the most magnificent building in Shanghai.2Many foreign experts live in the building.------In Shanghai, this is the most magnificent building in which many foreign experts live.三、練習(xí)
婚姻關(guān)系中人們爭(zhēng)論最多的問(wèn)題——如錢怎樣花——通常并非真正的問(wèn)題。關(guān)鍵的問(wèn)題是:誰(shuí)掌握控制權(quán)?年輕的時(shí)候,我對(duì)控制權(quán)的需要是源于害怕、缺乏信任和沒(méi)有安全感。最后我終于意識(shí)到我不需要控制妻子——實(shí)際上也不應(yīng)該控制她,而且不可能控制她,如果我試圖控制她,就會(huì)毀了我們的婚姻。
人們經(jīng)常把放棄控制權(quán)與軟弱混為一談。但家庭爭(zhēng)論中的勝利者從來(lái)都不是真正的勝利者。在你贏得爭(zhēng)論而你的伴侶屈服時(shí),你已經(jīng)輸了。這聽起來(lái)似乎相矛盾,卻千真萬(wàn)確。
第二篇:復(fù)合句翻譯練習(xí)
1.Since western fast food was introduced into China ten years ago, great changes have taken place in our eating habits.自從十年前西式快餐進(jìn)入中國(guó)以來(lái),我們的飲食習(xí)慣發(fā)生了巨大的變化。
2.As long as everyone is fully aware of the risks of obesity and take effective measures, I am sure that we can have more health.只要每個(gè)人都充分意識(shí)到肥胖的危害性并且采取有效措施,我肯定我們一定能過(guò)得更健康。
3.All that the advocates say is ______________________________.支持者所說(shuō)的一切均是站不住腳的。
4.I am now complaining about the guy ______________________________________________.我要投訴剛搬到我家隔壁來(lái)的那個(gè)家伙。
5.It is imperative that____________________________________________________________.采取有效措施來(lái)結(jié)束日益惡化的空氣污染勢(shì)在必行。
6.It is commonly believed that _____________________________________________________人們普遍認(rèn)為太空探索能促進(jìn)科學(xué)事業(yè)的發(fā)展。
7.Some people hold that __________________________________________________________.有些人認(rèn)為旅游業(yè)的發(fā)展對(duì)傳統(tǒng)文化產(chǎn)生一些負(fù)面的影響。
8.I can hardly agree with / support the proposal_______________________________________.我很難認(rèn)同婦女應(yīng)該回家做全職太太的建議。
9.The most practical countermeasure is that __________________________________________.最實(shí)際的對(duì)策是制定更嚴(yán)厲的法律和法規(guī)來(lái)懲處違規(guī)者。
10.____________________________________________________________________________
______________________________________________________________________________.當(dāng)每個(gè)人都充分意識(shí)到環(huán)保的重要性,并采取可行的措施,我堅(jiān)信我們能享有更干凈的環(huán)境。
11.It is true that the
_______________________________________________________________________________
___________________________________________but this not to say that they are without disadvantages.奧運(yùn)會(huì)增進(jìn)各國(guó)友誼和促進(jìn)主辦國(guó)的經(jīng)濟(jì)發(fā)展,但這并非意味著奧運(yùn)會(huì)是完美無(wú)缺的。
12.____________________________________________________________________________ ______________________________________________________________________________.因?yàn)槁糜螛I(yè)有助于增進(jìn)人們之間的了解,它將最終消除對(duì)其他國(guó)家的偏見,從而使世界變得更加和平。
第三篇:英語(yǔ)句子結(jié)構(gòu)分析英語(yǔ)句子分為簡(jiǎn)單句和復(fù)合句
英語(yǔ)句子結(jié)構(gòu)分析英語(yǔ)句子分為簡(jiǎn)單句和復(fù)合句。所謂的簡(jiǎn)單句,就是一個(gè)句子中只包含一個(gè)主謂結(jié)構(gòu)的句子。復(fù)合句又分成并列句和復(fù)雜句,下面我們分別對(duì)這三種情況加以簡(jiǎn)要的分析。
1、簡(jiǎn)單句簡(jiǎn)單句,即只有一個(gè)主謂結(jié)構(gòu)的句子。除了特殊情況,英語(yǔ)句子中都有主語(yǔ)、謂語(yǔ)(或表語(yǔ)),有時(shí)候還有賓語(yǔ);而且除了倒裝句等特殊句型,一般情況下,主語(yǔ)、謂語(yǔ)、賓語(yǔ)的先后順序是固定的,不可能賓語(yǔ)跑到謂語(yǔ)前面,或者謂語(yǔ)跑到主語(yǔ)前面。目前很多語(yǔ)法書都把英語(yǔ)的簡(jiǎn)單句歸納為五種基本句型。實(shí)際上,英語(yǔ)簡(jiǎn)單句還可以簡(jiǎn)化為三種形式:主語(yǔ) + 謂語(yǔ)(及物動(dòng)詞)+ 賓語(yǔ);I hate grammar.主語(yǔ) + 謂語(yǔ)(不及物動(dòng)詞);Grammar sucks.主語(yǔ) + 系動(dòng)詞 + 表語(yǔ) Grammar is hell.所以,我們?cè)陂喿x句子的時(shí)候,不管句子有多長(zhǎng),不管是并列句還是復(fù)合句,都必須首先分清各句中的主語(yǔ)、謂語(yǔ)(或表語(yǔ)),有的句子中還包括賓語(yǔ)。因?yàn)橹髡Z(yǔ)、謂語(yǔ)、賓語(yǔ)中英語(yǔ)句子的主干,抓住了句子的主干,句子的基本意思就清楚了。
2、并列句并列句就是兩個(gè)或以上的簡(jiǎn)單句,由表示并列關(guān)系的連詞或標(biāo)點(diǎn)符號(hào)連接而成。常見的連詞:and, not only...but also, neither...nor...or, either...or...otherwise,but, yet, while, so, for等。閱讀中遇到并列關(guān)系的句子,一般情況下是以連詞為界限,將句子分成前、后幾個(gè)部分,并分別來(lái)分析,各句的意思一般可以單獨(dú)理解,最后將各句合并即可。I hate grammar, / while he loves it.(以while為界,可分為前后兩個(gè)小句子)
3、主從復(fù)合句主從復(fù)合句即是復(fù)雜句,它也是由兩個(gè)以上的句子構(gòu)成。與并列不同的是,各分句之間的意思是緊密相連的,所以我們不能簡(jiǎn)單地把各個(gè)句子拆開來(lái)看,而必須將各分句綜合起來(lái)進(jìn)行理解。有時(shí)候,分句里面有可能還包含分句。
第四篇:簡(jiǎn)單句翻譯練習(xí)一
句子翻譯練習(xí)
A 1,他因?yàn)樯〔荒艹鱿瘯?huì)議 He didn’t attend the meeting because of illness/he was ill.2,那幅有吸引力的畫吸引了我的注意 The/That attractive painting attracts my attention.3,他避免麻煩我 He avoid bothering me.4,他以為我不喜歡蘋果和橘子 He thinks I don’t like apples and oranges.5,我喜歡畫畫和讀書 I enjoy/like/love writing and reading.6,不幸地,他生病了 Unfortunately/ Unluckily, he was ill.7,因?yàn)榇笥晁蠈W(xué)遲到了 He was late for school because of heavy rain/ He went to school late because it rained heavily.8,他因生病缺席了會(huì)議 He was absent from the meeting because of illness/ because he was ill.9,他出席了會(huì)議 He was present at the meeting.10, 你在說(shuō)話的時(shí)候,其實(shí)他在聽 Actually, he was listening when you talked.11,他在聽由Mary唱的歌 He was listening to the songs sung by Mary.12,請(qǐng)認(rèn)真聽老師說(shuō) Please listen to the teacher carefully 13,.這場(chǎng)大雨持續(xù)了兩個(gè)小時(shí)。That heavy rain lasted two hours.1 / 10
14, 在世界上,事物總是變化的。Things are always changing in the world./Things always change in the world.15,他只能放棄他的妻子和孩子 He had to abandon his wife and children./He had no choice but to abandon his wife and children.16,他會(huì)寫詩(shī)/游泳 He can write/swim./ He is able to write./ He has the ability of writing.17,他正全神貫注地學(xué)習(xí)He is absorbed in studying./ He concentrates / focuses(himself)on studying.18,這幅畫很抽象 That painting is very abstract.19,食物非常豐富 The food is very abundant.20在我看來(lái),你是對(duì)的 According to me / From my point of view/In my opinion, you are right.21,長(zhǎng)大后我想要成為一名會(huì)計(jì) I want to become an accountant when I grow up.22,我們應(yīng)該為下次比賽積累經(jīng)驗(yàn) We should accumulate experience for the next competition.23,我已經(jīng)習(xí)慣了在這個(gè)學(xué)校學(xué)習(xí)I have been used /accustomed to studying in the school.24,他獲得了打獵的技巧 He acquire /gain/get the skill of hunting, 25,他積極參加比賽He take an active part in the competition./He takes part in the competition actively.2 / 10
26,這個(gè)男(女)演員擅長(zhǎng)表演/在表演方面很有技巧 That actor/actress is skilled /skillful at /is good at/does well in acting.27,事實(shí)上,他希望被那所大學(xué)錄取Actually, he hopes to be admitted by that university./The fact is that he hopes to be admitted by that university.28,他可以很好地適應(yīng)新環(huán)境He can adapt(himself)to the new environment quickly.29,他可以適應(yīng)每天早早起床 He can adapt(himself)to getting up early everyday/every morning.30,如果茶太濃了,再加多點(diǎn)水。If the tea is too heavy, please add more water.31,我不喜歡油膩 /清淡的食物 I don’t like heavy/ light food.32,暴雨即將來(lái)臨 Heavy rain is coming.33,惡劣的天氣整加了我們的困難 The terrible weather adds to our difficulty.34,他增加了我們的麻煩 He adds to our trouble.35,請(qǐng)將黃油添加到面包上 Please add some butter to the bread.36,三加三等于六 If you add three to three, you get six.37,你應(yīng)該根據(jù)天氣對(duì)你的安排做出調(diào)整 You should adjust your arrangement according to the weather.3 / 10
38,他根據(jù)高考的要求對(duì)自己的學(xué)習(xí)方法進(jìn)行了調(diào)整 He adjust his learning method according to the requirement of the college entrance examination.39,他吸煙/吸毒成癮 He is addicted to drugs/ smoking 40,他沉迷于看電視/看小說(shuō) He is addicted to watching TV/ reading novels.41,他非常欽佩他的偶像/他的偶像值得欽佩 He admires his idol very much./ His idol is admirable.42,我們?cè)谥星锕?jié)會(huì)賞月 We admire the moon in the Mid-autumn Festival.43,他承認(rèn)考試作弊/考試不及格He admits cheating on the exam.44,他承認(rèn)欺騙了她 He admits cheating her.45,這對(duì)年輕的夫婦收養(yǎng)了一個(gè)聰明的小男孩 The young couple adopted a clever young boy.46,他的發(fā)明推進(jìn)了社會(huì)的發(fā)展 His invention advances the development of the society.47,先進(jìn)的發(fā)明使得我們的生活非常方便 Advanced inventions make our lives very convenient, 48,這手機(jī)既有優(yōu)點(diǎn)也有缺點(diǎn) This phone has advantages and disadvantages.49,他利用你去達(dá)到他的目的 He takes the advantage of you to achieve his aims/goals.4 / 10
50,他為了通過(guò)考試冒險(xiǎn)作弊 He takes adventure to cheat on the exam in order to pass the exam.51,這家公司在電視上為新出版的書做廣告 The company advertises the new-published book on TV.52,請(qǐng)給我一些學(xué)習(xí)方面的建議Please give me some advise on study.53,我建議他勤奮學(xué)習(xí)We advises him to study hard.54,我建議她上課認(rèn)真聽講I advise her to listen carefully in class 55,我們提倡和平相處We advocate getting along with each other in peacefully./ We advocate living in peace.56,他的演講深深地影響了我 His speech affects me deeply.57,噪音影響了他的學(xué)習(xí)The noise affects his study.58,他家付不起學(xué)費(fèi)His family can not afford the school fees.59,他承擔(dān)不起失去工作的后果 He can’t afford to lose his job.60,士兵們勇敢地與洪水作斗爭(zhēng)The soldiers fight bravely against the blood.61,他同意放棄自己的學(xué)業(yè) He agree to give up his study.62,他還活著 He is still alive.63,他不允許我吸煙 He doesn’t allow me to smoke.64,他不允許我到外面去/他不允許我跟我的朋友們?cè)诮稚祥e逛 He doesn’t allow me to go outside/He doesn’t allow me to hanging 5 / 10
out with my friends.65,他一個(gè)人住,但他不覺得孤獨(dú)He lives alone ,but he doesn’t feel lonely.66,他們?cè)诤0?000米的地方野餐They have a picnic at an altitude of 1000 meters.67,他對(duì)她的態(tài)度非常糟糕 His attitude towards her is very bad 68 ,在古代,君王們雄心勃勃 In the ancient time ,the emperors are very ambitious.69,數(shù)額總計(jì)為200,000 The sum adds up to 200,000.70,他的笑話把我逗樂(lè)了 His joke amuses me.71,他宣布下課 He announce that the class is over.72,他誠(chéng)心向道歉 He expresses his apology to you sincerely./He apologizes to you sincerely./ He expresses sincere apology to you.73,顯然,他贏得了比賽Apparently, he won the game.74,觀眾熱烈地為他鼓掌 The audience applaud for him heatedly.75,我們應(yīng)該學(xué)會(huì)把理論運(yùn)用到實(shí)踐中去 We should learn to apply theory to practice.76,我非常感激你的幫忙I appreciate your help.77,他正在欣賞那幅名畫He is appreciating that famous painting.78,小偷慢慢靠近了那棟樓The thief approaches that building slowly.6 / 10
79,我不知道解決這個(gè)問(wèn)題的方法 I don’t know the approach of solving the problem/ I don’t know the approach to solve the problem.80,他們相互爭(zhēng)吵起來(lái) They argue with each other.81,我們應(yīng)該用知識(shí)武裝自己 We should arm ourselves with knowledge.82,他一到達(dá)機(jī)場(chǎng),警察就將他逮捕了 The police arrested him at his arrival at the airport 83,那護(hù)士協(xié)助醫(yī)生對(duì)那個(gè)病人做手術(shù) The nurse assists the doctor in operating on that patient.84,我將他與小偷/那場(chǎng)車禍聯(lián)系起來(lái) I associated him with thief/ the car accident.85,這里的氣氛非常奇怪 The atmosphere here is very strange.86,他嘗試把那支筆撿起來(lái) He attempt to pick up that pen.87,敵人襲擊了他們 The enemy attacked them.88,我們需要注意這些嚴(yán)肅的問(wèn)題 We should pay attention to these serious problem.B 1,那個(gè)年輕的單身男子有一個(gè)可愛的小嬰兒需要去照顧。That young bachelor has a lovely baby to take care of.2,如果你們知道我的家庭背景,請(qǐng)向后退 If you know my family background ,please step backward.7 / 10
3,那個(gè)面包師在他的面包店里烤面包That baker is baking bread in his bakery.4,我建議你們?nèi)ャy行開一個(gè)銀行賬戶I advise you to open a bank account in the bank.5,這本書是以我自己真實(shí)的經(jīng)歷為基礎(chǔ)的 This book is based on my own experience.6,他把自己的棒球球拍放在黑暗的地下室里。He put his baseball bat in the black basement.7,他的包里放著一條巧克力和一瓶啤酒There is a bar of chocolate and a bottle of beer in his bag.8,他無(wú)法忍受桌子上那發(fā)臭的牛肉,所以他把牛肉扔掉了。He couldn’t bear the smelly beef, so he threw it away.9,書店里的書架上有很多新出版的書 There are many newly-published
books
in
the
bookshelf
in
the bookshop/bookstore.10,這家分公司的生意非常繁榮 Business of this branch is booming.11,那個(gè)憂郁的盲人沒(méi)辦法填表格,所以他覺得很痛苦 That blue blind man couldn’t fill in the blank, so he feels very painful/bitter.12,他感覺到非常厭倦,因?yàn)檫@場(chǎng)籃球比賽實(shí)在太無(wú)聊了He felt very bored, because the basketball game is very boring.8 / 10
13,在會(huì)議的開始,你就應(yīng)該告訴我們你是代表你的老板到這里來(lái)的。At the beginning of the meeting, you should have told us that you came here on the behalf of your boss.14,在海灘上,那棟建筑后面有一張彎曲的長(zhǎng)凳 On the beach, there is a bent bench behind the building.15,那個(gè)帥氣的新郎和那個(gè)漂亮的新娘是在寬闊的海灘遇到對(duì)方的。That handsome bridegroom met with the beautiful bride on the broad beach.16,請(qǐng)?jiān)谖一丶抑鞍阉疅_ Please boil the water before I come back home.17,那個(gè)勇敢的小男孩通過(guò)石頭之間的間隙遞給我一塊面包和一瓶牛奶 The brave boy passed me a piece of bred and a bottle of milk through the break between rocks.18,鳥籠里面的那些鳥沒(méi)辦法在藍(lán)天里自由飛翔 The bird in the birdcage can’t fly freely in the blue sky.19,白色地毯上的血跡讓我們感到觸目驚心。The blood in the white blanket scared us.20,士兵在戰(zhàn)場(chǎng)上英勇地與敵人作斗爭(zhēng) The soldiers battled against the enemy bravely on the battleground.21,桌子底下那個(gè)籃球是件真正的便宜貨The basketball below the desk is a real bargain.22,自從他出生以來(lái),他的出生地就給他留下了深刻無(wú)比的印象,所 9 / 10
以每年生日他都會(huì)回到那里去 Since his birth, his birthplace impresses him deeply/leaves deep impression on him.So he goes back there every birthday.23,當(dāng)公共汽車駛過(guò)公交車站時(shí),他突然放聲大哭起來(lái)He burst into tears/crying when the bus passed the bus station.24,那女企業(yè)家如此忙碌以至于她衣服的扣子壞了也沒(méi)有注意到 That businesswomen is so busy that she doesn’t notice that the button of her clothes is broken.25,一只蜜蜂和一只蝴蝶繞著一束玫瑰花飛來(lái)飛去
There is a bee and a butterfly flying around a bunch of roeses.10 / 10
第五篇:翻譯漢語(yǔ)
液壓系統(tǒng)與氣壓系統(tǒng)
液壓傳動(dòng)和氣壓傳動(dòng)稱為流體傳動(dòng),是根據(jù)17世紀(jì)帕斯卡提出的液體靜壓力傳動(dòng)原理而發(fā)展起來(lái)的一門新興技術(shù),1795年英國(guó)約瑟夫?布拉曼(Joseph Braman,1749-1814),在倫敦用水作為工作介質(zhì),以水壓機(jī)的形式將其應(yīng)用于工業(yè)上,誕生了世界上第一臺(tái)水壓機(jī)。1905年將工作介質(zhì)水改為油,又進(jìn)一步得到改善。
第一次世界大戰(zhàn)(1914-1918)后液壓傳動(dòng)廣泛應(yīng)用,特別是1920年以后,發(fā)展更為迅速。液壓元件大約在 19 世紀(jì)末 20 世紀(jì)初的20年間,才開始進(jìn)入正規(guī)的工業(yè)生產(chǎn)階段。1925 年維克斯(F.Vikers)發(fā)明了壓力平衡式葉片泵,為近代液壓元件工業(yè)或液壓傳動(dòng)的逐步建立奠定了基礎(chǔ)。20 世紀(jì)初康斯坦丁?尼斯克(G?Constantimsco)對(duì)能量波動(dòng)傳遞所進(jìn)行的理論及實(shí)際研究;1910年對(duì)液力傳動(dòng)(液力聯(lián)軸節(jié)、液力變矩器等)方面的貢獻(xiàn),使這兩方面領(lǐng)域得到了發(fā)展。
第二次世界大戰(zhàn)(1941-1945)期間,在美國(guó)機(jī)床中有30%應(yīng)用了液壓傳動(dòng)。應(yīng)該指出,日本液壓傳動(dòng)的發(fā)展較歐美等國(guó)家晚了近20 多年。在 1955 年前后 , 日本迅速發(fā)展液壓傳動(dòng),1956 年成立了“液壓工業(yè)會(huì)”。近20~30 年間,日本液壓傳動(dòng)發(fā)展之快,居世界領(lǐng)先地位。
液壓傳動(dòng)有許多突出的優(yōu)點(diǎn),因此它的應(yīng)用非常廣泛,如一般工業(yè)用的塑料加工機(jī)械、壓力機(jī)械、機(jī)床等;行走機(jī)械中的工程機(jī)械、建筑機(jī)械、農(nóng)業(yè)機(jī)械、汽車等;鋼鐵工業(yè)用的冶金機(jī)械、提升裝置、軋輥調(diào)整裝置等;土木水利工程用的防洪閘門及堤壩裝置、河床升降裝置、橋梁操縱機(jī)構(gòu)等;發(fā)電廠渦輪機(jī)調(diào)速裝置、核發(fā)電廠等等;船舶用的甲板起重機(jī)械(絞車)、船頭門、艙壁閥、船尾推進(jìn)器等;特殊技術(shù)用的巨型天線控制裝置、測(cè)量浮標(biāo)、升降旋轉(zhuǎn)舞臺(tái)等;軍事工業(yè)用的火炮操縱裝置、船舶減搖裝置、飛行器仿真、飛機(jī)起落架的收放裝置和方向舵控制裝置等
傳遞動(dòng)力只有三種方法:電傳動(dòng)、機(jī)械傳動(dòng)、液壓傳動(dòng)。實(shí)際上,許多設(shè)備將這三種方式組合起來(lái)形成一個(gè)更有效的系統(tǒng)。知道三種方式的各自突出優(yōu)點(diǎn)是確定哪種方法是最好的傳遞方式的重要因素。例如:液壓比機(jī)械能夠更有效的進(jìn)行遠(yuǎn)距離傳遞。然而,液壓傳動(dòng)沒(méi)有電傳動(dòng)的距離遠(yuǎn)。
液壓動(dòng)力系統(tǒng)一般比較關(guān)注調(diào)節(jié)流量和控制壓力,這樣的系統(tǒng)一般包括:
1.泵是一種將原動(dòng)力轉(zhuǎn)化成液體壓力的機(jī)構(gòu)。
2.閥是用來(lái)控制泵的輸出流量的方向、產(chǎn)生壓力的大小和流量的大小。能量的大小是通過(guò)控制流量和壓力的大小所決定的。3.執(zhí)行機(jī)構(gòu)是在需要的地方將液壓能轉(zhuǎn)換成可用的機(jī)械能的機(jī)構(gòu)。
4.傳遞介質(zhì)是液體,其提供剛性傳動(dòng)和控制,被密封在閥處提供潤(rùn)滑作用以及起冷卻系統(tǒng)的作用。
5.連接件,是用來(lái)連接各種系統(tǒng)組件,傳遞壓力油液并使油液返回油箱。
6.油箱和冷卻器,是分別用來(lái)保證油液質(zhì)量和冷卻油液的。7.氣動(dòng)系統(tǒng)需要通過(guò)油霧器向從調(diào)壓閥出來(lái)的氣體中撒入潤(rùn)滑油。這是為了防止氣動(dòng)系統(tǒng)配合件間的磨損。
液壓系統(tǒng)是用于工業(yè)應(yīng)用,如沖壓機(jī)、鋼鐵廠、制造業(yè)、農(nóng)業(yè)機(jī)械、礦業(yè)、航空、空間技術(shù)、深??碧健⒔煌?、海洋技術(shù)、海上天然氣和石油勘探。簡(jiǎn)言之,每個(gè)人的生活都要受益于液壓技術(shù)。放電加工又叫做電鍍或者電火花加工,是基于火花放電侵蝕金屬的原理。我們知道當(dāng)兩根帶電的導(dǎo)線接觸時(shí)會(huì)產(chǎn)生電弧,如果我們仔細(xì)觀察連接兩根導(dǎo)線的金屬時(shí)會(huì)注意到一小部分金屬已經(jīng)被侵蝕掉留下了一個(gè)小坑。
基本的電火花加工系統(tǒng)是由一個(gè)連接到直流電源的形狀工具和工件及其兩者之間的電介質(zhì)組成,這是一種最廣泛使用的加工過(guò)程,尤其是刻鍛操作——當(dāng)工具與工件件的電位差足夠高時(shí)通過(guò)電流的瞬間放電,從工件表面移除非常少得金屬。
機(jī)械控制包括凸輪和調(diào)速。盡管他們已經(jīng)被用于比較復(fù)雜的機(jī)器,但為了更加經(jīng)濟(jì),今天它們被用于簡(jiǎn)單和固定周期控制。一些自動(dòng)化機(jī)器,如螺桿機(jī),仍然使用凸輪基礎(chǔ)控制。機(jī)械控制機(jī)構(gòu)很難制造但不容易磨損。
但氣動(dòng)控制在某些應(yīng)用上仍非常受歡迎,它是由壓縮空氣、氣動(dòng)閥和轉(zhuǎn)換開關(guān)組成的簡(jiǎn)單邏輯控制系統(tǒng)。雖然容易反應(yīng)遲緩,但由于是由標(biāo)準(zhǔn)件構(gòu)筑邏輯,因此比機(jī)械控制容易建立。氣動(dòng)控制系統(tǒng)容易受磨損。
像機(jī)械控制系統(tǒng)一樣,機(jī)電控制系統(tǒng)使用開關(guān)、繼電器、時(shí)間計(jì)數(shù)器等等來(lái)構(gòu)建邏輯,它更加快和靈活??刂破鞑捎脵C(jī)電控制被稱為中繼設(shè)備。
流體動(dòng)力是自動(dòng)化系統(tǒng)的肌肉,是因?yàn)橐幌滤膫€(gè)方面: 1.簡(jiǎn)單而精確的控制。通過(guò)簡(jiǎn)單的杠桿原理,流體動(dòng)力系統(tǒng)可以輕松的啟動(dòng)、停止、加速或者減速,并且定位動(dòng)力可以提供任何的動(dòng)力需要而使定位偏差精確到1/10000英寸。2.成倍的動(dòng)力。液壓系統(tǒng)可以簡(jiǎn)單而有效的將一盎司的力轉(zhuǎn)換成百噸的輸出力。3.恒定的力或轉(zhuǎn)矩。只有液壓系統(tǒng)可以不管速度怎么變化保持提供恒或力轉(zhuǎn)矩,這可以適應(yīng)不論是輸出的速度或轉(zhuǎn)速是幾英寸每小時(shí)、幾百英寸每秒還是幾轉(zhuǎn)每小時(shí)、幾千轉(zhuǎn)每秒。4.簡(jiǎn)單、安全、經(jīng)濟(jì),一般情況下液壓系統(tǒng)可以比機(jī)械或者電力系統(tǒng)用更少的零件實(shí)現(xiàn)同樣的功能。
因?yàn)樗鼈兊暮?jiǎn)單維護(hù)和操作而使安全度和可靠性實(shí)現(xiàn)最大化。例如,新的轉(zhuǎn)向機(jī)構(gòu)的產(chǎn)生使得其他車輛的電力系統(tǒng)顯得陳舊,轉(zhuǎn)向單元有在一個(gè)整體上得許多手動(dòng)操作的方向控制閥和進(jìn)油調(diào)壓閥組成。運(yùn)輸、海洋技術(shù)、海上天然氣和石油勘探等各個(gè)領(lǐng)域都離不開液壓。它提供了簡(jiǎn)單的系統(tǒng)。另外,很小的輸入扭矩去控制最難得應(yīng)用。在有限的空間里需要一個(gè)小得轉(zhuǎn)向機(jī)構(gòu)是非常必要的而且能夠減少操作者的疲勞。液壓系統(tǒng)的另外一個(gè)好處就是可以立即進(jìn)行可逆運(yùn)行。自動(dòng)的過(guò)載保護(hù)和無(wú)級(jí)變速控制。液壓系統(tǒng)可以有比任何一直電源都高的動(dòng)力。盡管液壓有這么多的優(yōu)勢(shì)但也不能代替所有的動(dòng)力傳遞。氣動(dòng)系統(tǒng)
氣動(dòng)系統(tǒng)是依靠壓縮氣體來(lái)進(jìn)行傳遞和控制的。氣壓系統(tǒng)通常用空氣(不用其他氣體)作為流體介質(zhì),因?yàn)榭諝馐前踩⒊杀镜投蛛S處可得的流體,在系統(tǒng)部件中產(chǎn)生電弧有可能點(diǎn)燃泄漏物的場(chǎng)合下(使用空氣作為介質(zhì))尤其安全。在氣動(dòng)系統(tǒng)中,壓縮機(jī)是用于壓縮和供應(yīng)充足的空氣,壓縮機(jī)通常有活塞式、葉片式或螺釘式。一般的壓縮機(jī)是靠壓縮體積來(lái)增加空氣壓力。氣動(dòng)系統(tǒng)通常使用一個(gè)大型集中的空氣壓縮機(jī),并認(rèn)為它是無(wú)限大的??諝庠搭愃朴陔娏ο到y(tǒng)只需將插頭插入就可以獲得電力。這樣壓縮空氣管道可以從一個(gè)氣源引出接到整個(gè)工廠的不同地方。壓縮空氣可以通過(guò)過(guò)濾器將空氣中的污染物去除,這些污染物將會(huì)損壞氣動(dòng)系統(tǒng)的配合部件,例如閥和氣缸。之后壓縮空氣經(jīng)過(guò)一個(gè)減壓閥將壓縮空氣的壓力降到特定應(yīng)用所需的值。由于空氣沒(méi)有好的潤(rùn)滑效果(包含20%的氧氣),氣動(dòng)系統(tǒng)需要一個(gè)油霧器將潤(rùn)滑油注射到從調(diào)壓器輸出來(lái)的壓縮氣體中。這樣可以防止有配合移動(dòng)的氣動(dòng)部件的損壞。大氣中的空氣含有不同程度的水分,這些水分會(huì)洗掉潤(rùn)滑劑從而導(dǎo)致過(guò)度磨損和腐蝕,因此,在某些應(yīng)用中需要空氣干燥劑來(lái)消除這些不良的水分。因?yàn)闅鈩?dòng)系統(tǒng)排氣直接進(jìn)入大氣,將會(huì)帶來(lái)噪音,因此消聲器安裝在排氣閥口和執(zhí)行件處以減少噪聲,并且使操縱人員避免噪聲和灰塵顆粒的污染。氣動(dòng)系統(tǒng)將代替液壓系統(tǒng)的可能性原因有以下幾個(gè)因素;
液體的慣性比氣體的大,因此在加速和減速、啟動(dòng)和制動(dòng)時(shí)存在潛在的問(wèn)題。
由于牛頓定律(F=m×a),將油液加速所需的力比將氣體加速到同樣值所需要的力要大很多倍,這導(dǎo)致更大的摩擦壓力和功率損失。而且液壓系統(tǒng)采用的油液介質(zhì)與氣體不同,它需要設(shè)置特制的儲(chǔ)存油箱和無(wú)泄漏回油系統(tǒng)。液壓系統(tǒng) 工程液壓回路 泵就是用來(lái)提供壓力油的也可以說(shuō)是提供動(dòng)力。閥是用來(lái)控制油的流量和控制提供需要的壓力。每一個(gè)液壓動(dòng)力系統(tǒng)用一個(gè)或者多個(gè)泵提供液壓油。從液壓動(dòng)力系統(tǒng)出來(lái)的液壓油完成工作。壓力油用來(lái)推動(dòng)活塞桿在氣缸中運(yùn)動(dòng)或者使液壓馬達(dá)的軸轉(zhuǎn)動(dòng)。泵的作用就是液壓動(dòng)力系統(tǒng)中將油液加壓以完成工作。一些動(dòng)力系統(tǒng)使用低壓100pi來(lái)完成工作。當(dāng)需要大功率輸出時(shí)可以達(dá)到10000pi或者更多,所以我們發(fā)現(xiàn)現(xiàn)在的一些液壓動(dòng)力系統(tǒng)是由至少一個(gè)泵來(lái)加壓油液的。泵的種類
三種類型的泵應(yīng)用在泵的動(dòng)力系統(tǒng)中。(1)回轉(zhuǎn)泵(2)往復(fù)泵(3)離心泵。在泵的特性匹配中,使泵的最好的特點(diǎn)完成特殊的工作是一種趨勢(shì),例如,一個(gè)離心泵可以和一根柱塞泵串聯(lián)一起提供壓力油??刂崎y
壓力控制閥用來(lái)保證不同回路所需的壓力值,壓力控制閥利用將高壓區(qū)的油轉(zhuǎn)移到低壓區(qū)從而保證高壓區(qū)的壓力。閥可以分為安全閥、減壓閥、平衡閥、順序閥和卸荷閥。