旋風(fēng)除塵器的設(shè)計(jì)
旋風(fēng)除塵器的設(shè)計(jì),旋風(fēng)除塵器的設(shè)計(jì),旋風(fēng),除塵器,設(shè)計(jì)
主要參考文獻(xiàn)：1唐敬麟,張祿虎.除塵裝置系統(tǒng)及設(shè)備選用手冊.北京:化學(xué)工業(yè)出版社,20032第七屆全國顆粒制備與處理學(xué)術(shù)暨應(yīng)用研討會(專輯),中國粉體技術(shù)雜志社,2004(10)3龐新新, 向曉東, 陳寶智. 二次揚(yáng)塵對旋風(fēng)器除塵效率影響分析與對策. 武漢科技大學(xué)學(xué)報(bào)(自然科學(xué)版), 2001, 24 (3) : 253256 4向曉東. 現(xiàn)代除塵理論與技術(shù). 北京: 冶金工業(yè)出版社, 2002 5金國淼. 除塵設(shè)備. 北京: 化學(xué)工業(yè)出版社, 2002 6向曉東, 幸福堂, 余戰(zhàn)橋等. 環(huán)縫氣墊高效耐磨旋風(fēng)除塵器的研究. 通風(fēng)除塵, 1998, (1) : 2529 7.吳建蓉、王一飛、于榮賢等. 工程力學(xué)與機(jī)械設(shè)計(jì)基礎(chǔ), 電子工業(yè)出版社, ISBN 7-5053-8734-0/TN 18008. 黃忠耀、李冬梅、王景先等. Pro/ENGINEER 2001 基礎(chǔ)訓(xùn)練教程, 清華大學(xué)出版社 ISBN 7-900643-73-79. 張學(xué)軍等. Pro/ENGINEER Wildfire 機(jī)械設(shè)計(jì)與應(yīng)用 國防工業(yè)出版社 ISBN 7-118-04363-X/TH 19310. 王大康、盧頌峰等. 機(jī)械設(shè)計(jì)課程設(shè)計(jì)Machine, 北京工業(yè)大學(xué)出版社ISBN 7-5639-0880-3/G 47811. 王加信, 旋轉(zhuǎn)葉輪供料器新產(chǎn)品,上海信禾機(jī)械制造有限公司,20001012. 阮竟蘭 徐蕓 (鄭州糧食學(xué)院 450052)、馬仁貴 (合肥糧食機(jī)械廠 230000), 閉風(fēng)器結(jié)構(gòu)設(shè)計(jì)中的技術(shù)特點(diǎn)13 趙云嶺,王偉民 計(jì)算機(jī)工程制圖, 河南大學(xué)出版社, ISBN 7-81091-117-1/T 5214Kim H T, Lee K W, Kuhlman M R. Exploratory design modifications for15RosinP,RammlerE,IntelmannW.Grundlagenundgrenzender zyklonentstaubungJ.ZVerDtsch Ing,1932,76(16) :433438. 16Lapple CE.Gravityandcentrifugal separationJ.Ind Hyg Q, 1950, (1) :40-45. 致謝： 我的這篇畢業(yè)設(shè)計(jì)的完成，首先應(yīng)當(dāng)歸功于指導(dǎo)老師李玉中老師。他無論是在室內(nèi)資料整理還是在論文的撰寫等各個(gè)方面都給予了大量的指導(dǎo)和幫助，令我不但完成了論文，也學(xué)到了許多書本上學(xué)不到的知識，受益匪淺，特致以深深的感謝。同時(shí)也要感謝其他同學(xué)的幫助，我們共同查找資料。另外還要感謝資料室及復(fù)印室的各位工作人員的幫助與合作。22論文題目畢業(yè)設(shè)計(jì)（論文）中圖分類號：旋風(fēng)除塵器的設(shè)計(jì)專業(yè)名稱：計(jì)算機(jī)輔助設(shè)計(jì)與制造學(xué)生姓名：李瑞鵬導(dǎo)師姓名：李玉中 焦作大學(xué)機(jī)電工程系 二00年5月焦作大學(xué)畢業(yè)設(shè)計(jì)（論文） 第1章（引言）隨著工業(yè)生產(chǎn)的迅速發(fā)展，工業(yè)垃圾的種類和排放量日益增多，防治環(huán)境污染的問題也日益引起人們的重視。工業(yè)垃圾的排放量可能是最先進(jìn)行控制的一個(gè)環(huán)境參數(shù)。據(jù)估算，目前全國的年排塵量約2700萬t，因此減少工業(yè)垃圾的排放受到相當(dāng)重視。 1995年8月修訂后的中華人民共和國環(huán)境污染防治法第三章規(guī)定：國家鼓勵(lì)企業(yè)采用先進(jìn)的除塵技術(shù)。除塵器是控制塵粒污染的有效措施，也是研究應(yīng)用較早的一項(xiàng)技術(shù)。但在塵粒初始量增加，排放量進(jìn)一步嚴(yán)格的情況下，企業(yè)必須重新計(jì)劃自己的操作條件和排放控制系統(tǒng)，開發(fā)或應(yīng)用更高效的除塵器，以滿足現(xiàn)行法規(guī)的要求。 作為控制大直徑顆粒物排放的最古老和常用裝置之一的旋風(fēng)除塵器，隨同，雖然其除塵效率教低，但如果和其他作用相聯(lián)合，如靜電作用和濕法作用等，可達(dá)到更高的除塵效率。 現(xiàn)在，很多人都在積極開發(fā)利用旋風(fēng)除塵器的潛能。利用靜電和離心力作用機(jī)理除塵的研究是近年來很活躍的領(lǐng)域，其目的就是研制出高效低耗的除塵設(shè)備，如湖南大學(xué)的龔光彩等人對靜電旋風(fēng)除塵器的研究，證明該類型除塵器有極低的阻力和較高的除塵效率。 雖然旋風(fēng)除塵器在我國應(yīng)用還不是很廣泛，但是隨著工業(yè)的發(fā)展以及人們生活水平和對環(huán)境質(zhì)量要求的提高，旋風(fēng)除塵器必將有越來越重要的應(yīng)用，而管式以其顯著的優(yōu)點(diǎn)將會在除塵器的未來發(fā)展中顯示越來越重要的作用，這可從發(fā)達(dá)國家除塵器發(fā)展的過程中得到證明；另一方面，開發(fā)新型除塵裝置也是大勢所趨?；谖覈奶厥鈬鴳c，這個(gè)過程可能還需要較長的一段時(shí)間，但無論如何，由中小型，低效除塵設(shè)備向大型高效除塵設(shè)備發(fā)展是 一個(gè)必然的趨勢。 旋風(fēng)除塵器是一種常見的氣固，氣液和液固分離設(shè)備。由于結(jié)構(gòu)簡單，造價(jià)低廉，操作簡便，運(yùn)行穩(wěn)定等特點(diǎn)，旋風(fēng)除塵器在機(jī)械，建材，輕工，冶金，化工，石油等行業(yè)得到廣泛應(yīng)用。理論與實(shí)驗(yàn)研究均以證明，旋風(fēng)除塵器的動力消耗中有相當(dāng)大一部分無益于分離，屬純消耗性能量損失。本設(shè)計(jì)闡述的是如何設(shè)計(jì)出新型高效除塵裝置。1中圖分類號： TQ172.6+88.2 旋風(fēng)收塵器 密級：UDC： 單位代碼：11522旋風(fēng)除塵器的設(shè)計(jì)Tornado in addition to the design of the dust machine姓 名李瑞鵬學(xué) 制三年專 業(yè)計(jì)算機(jī)輔助設(shè)計(jì)研究方向?qū)?師李玉中職 稱論文提交日期論文答辯日期 焦作大學(xué)機(jī)電工程系摘要：旋風(fēng)除塵器廣泛地應(yīng)用于各個(gè)行業(yè)除塵系統(tǒng)中，本文針對旋風(fēng)除塵器的結(jié)構(gòu)及工作原理，分析影響旋風(fēng)除塵器壓力損失的因素，介紹了旋風(fēng)除塵器內(nèi)部流場和除塵機(jī)理。針對旋風(fēng)除塵器除塵效率問題進(jìn)行了分析，總結(jié)了現(xiàn)有改進(jìn)方案，指出存在的不足，并結(jié)合前人的改進(jìn)思路提出了新的改進(jìn)方案，以提高旋風(fēng)除塵器的分離效率，為進(jìn)一步挖掘旋風(fēng)除塵器的潛在性能開辟新的思路。簡要地設(shè)計(jì)了一款旋風(fēng)除塵器，另外簡要的介紹了現(xiàn)有旋風(fēng)除塵器的幾種比較典型的改進(jìn)措施。關(guān)鍵詞： 旋風(fēng)除塵器 ；壓力損失； 分離效率； 改進(jìn)方案； ABSTRACT: cyclone deduster is broadly applied in each profession to separating dust. This article analyze the structure and working principles of cyclone de-duster , designed a type of cyclone de-duster .Keyword: cyclone de-duster; the pressure lose; Separating efficiency; Improve project; 焦作大學(xué)畢業(yè)設(shè)計(jì)（論文） 結(jié)論（最后一章）由以上設(shè)計(jì)可以看出，旋風(fēng)除塵器在提升、分離物料等得到廣泛的應(yīng)用，該裝置在提升物料1.5m3/h?；緷M足工業(yè)生產(chǎn)要求，本次設(shè)計(jì)的旋風(fēng)除塵器主要用于除去鋸末、灰塵或者用于提升、分離小麥、玉米、稻谷、沙粒等。焦作大學(xué)畢業(yè)設(shè)計(jì)（論文） 正文二.說明書2.1圖形設(shè)計(jì)： 旋風(fēng)除塵器圖（圖1）2.2設(shè)計(jì)數(shù)據(jù)： 表1 旋風(fēng)除塵器的幾何尺寸 名稱 數(shù)據(jù)旋風(fēng)除塵器半徑r0.4氣體出口管半徑r0.2粉塵出口管半徑r0.2出口管到底部高h(yuǎn)2.07園部高h(yuǎn)1.066氣體出口管長度l0.466入口管寬度b0.166入口管高度h0.466入口管面積A0.078錐角7.75總高度h2.54入口類型切線入口管型矩形 2.3旋風(fēng)除塵器的參數(shù)計(jì)算許多學(xué)者都致力于旋風(fēng)除塵器的研究，通過各種假設(shè)，他們提出了許多不同的計(jì)算方法。由于旋風(fēng)除塵器內(nèi)實(shí)際的氣、塵兩相流動非常復(fù)雜，因此根據(jù)某些假設(shè)條件得出的理論公式目前還不能進(jìn)行較精確的計(jì)算。 1.分割粒徑（dc50） 計(jì)算旋風(fēng)除塵器的分割粒徑（dc50）是確定除塵器效率的基礎(chǔ)。在計(jì)算時(shí)，因假設(shè)條件和選用系數(shù)不同，計(jì)算分割粒徑的公式也各不同。下面簡要介紹一種計(jì)算方法，以說明旋風(fēng)除塵器的除塵原理。處于外渦旋的塵粒在徑向會受到兩個(gè)力的作用：慣性離心力 （2-3-1）式中 vt塵粒的切線速度，可以近似認(rèn)為等于該點(diǎn)氣流的切線速度，m/s；r旋轉(zhuǎn)半徑，m。向心運(yùn)動的氣流給予塵粒的作用力 （2-3-2） 式中 w氣流與塵粒在徑向的相對運(yùn)動速度，m/s。 這兩個(gè)力方向相反，因此作用在塵粒上的合力 （2-3-3） 由于粒徑分布是連續(xù)的，必定存在某個(gè)臨界粒徑dk作用在該塵粒上的合力之和恰好為零，即F=FlP=0。這就是說，慣性離心力的向外推移作用與徑向氣流造成的向內(nèi)飄移作用恰好相等。對于粒徑dcdk的塵粒，因FlP，塵粒會在慣性離心力推動下移向外壁。對于dcdk的塵粒，因FlP，塵粒會在向心氣流推動下進(jìn)入內(nèi)渦旋。如果假想在旋風(fēng)除塵器內(nèi)有一張孔徑為dk的篩網(wǎng)在起篩分作用，粒徑dcdk的被截留在篩網(wǎng)一面，dcdk的則通過篩網(wǎng)排出。那么篩網(wǎng)置于什么位置呢?在內(nèi)、外渦旋交界面上切向速度最大，塵粒在該處所受到的慣性離心力也最大，因此可以設(shè)想篩網(wǎng)的位置應(yīng)位于內(nèi)、外渦旋交界面上。對于粒徑為dk的塵粒，因Fl=P，它將在交界面不停地旋轉(zhuǎn)。實(shí)際上由于氣流紊流等因素的影響，從概率統(tǒng)計(jì)的觀點(diǎn)看，處于這種狀態(tài)的塵粒有50的可能被捕集，有50的可能進(jìn)入內(nèi)渦旋，這種塵粒的分離效率為50。因此dk=dc50。根據(jù)公式（5-4-7），在內(nèi)外渦旋交界面上，當(dāng)Fl=P時(shí)， 旋風(fēng)除塵器的分割粒徑： （2-3-4） 式中 r0交界面的半徑，m；w0交界面上的氣流徑向速度，ms；v0t交界面上的氣流切向速度，ms。 應(yīng)當(dāng)指出，粉塵在旋風(fēng)除塵器內(nèi)的分離過程是很復(fù)雜的，上述計(jì)算方法具有某些不足之處。例如它只是分析單個(gè)塵粒在除塵器內(nèi)的運(yùn)動，沒有考慮塵粒相互間碰撞及局部渦流對塵粒分離的影響。由于塵粒之間的碰撞，粗大塵粒向外壁移動時(shí)，會帶著細(xì)小的塵粒一起運(yùn)動，結(jié)果有些理論上不能捕集的細(xì)小塵粒也會一起除下。相反，由于局部渦流和軸向氣流的影響，有些理論上應(yīng)被除下的粗大塵粒卻被卷入內(nèi)渦旋，排出除塵器。另外有些已分離的塵粒，在下落過程中也會重新波氣流帶走。外渦旋氣流在錐體底部旋轉(zhuǎn)向上時(shí)，會帶走部分已分離的塵粒，這種現(xiàn)象稱為返混。因此理論計(jì)算的結(jié)果和實(shí)際情況仍有一定差別。2.旋風(fēng)除塵器的阻力 由于氣流運(yùn)動的復(fù)雜性，旋風(fēng)除塵器阻力目前還難于用公式計(jì)算，一般要通過試驗(yàn)或現(xiàn)場實(shí)測確定。旋風(fēng)除塵器的阻力： （2-3-5） 式中 局部阻力系數(shù)，通過實(shí)測求得；u進(jìn)口速度，ms；氣體的密度，kgm3， 2.4 設(shè)計(jì)要求 .粉狀物料提升裝置中旋風(fēng)除塵器的研究現(xiàn)狀 .了解其工作場所要求及原理 .確定總體方案和各部分結(jié)構(gòu)方案 .畫圖 .部分設(shè)計(jì)計(jì)算 三.旋風(fēng)除塵器的原理及應(yīng)用3.1旋風(fēng)除塵器的原理旋風(fēng)除塵器是利用旋轉(zhuǎn)氣流所產(chǎn)生的離心力將塵粒從合塵氣流中分離出來的除塵裝置。它具有結(jié)構(gòu)簡單，體積較小，不需特殊的附屬設(shè)備，造價(jià)較低阻力中等，器內(nèi)無運(yùn)動部件，操作維修方便等優(yōu)點(diǎn)。旋風(fēng)除塵器一般用于捕集5-15微米以上的顆粒除塵效率可達(dá)80以上，近年來經(jīng)改進(jìn)后的特制旋風(fēng)除塵器其除塵效率可達(dá)5以上。旋風(fēng)除塵器的缺點(diǎn)是捕集微粒小于5微米的效率不高 旋風(fēng)除塵器內(nèi)氣流與塵粒的運(yùn)動概況： 旋轉(zhuǎn)氣流的絕大部分沿器壁自圓簡體，呈螺旋狀由上向下向圓錐體底部運(yùn)動，形成下降的外旋含塵氣流，在強(qiáng)烈旋轉(zhuǎn)過程中所產(chǎn)生的離心力將密度遠(yuǎn)遠(yuǎn)大于氣體的塵粒甩向器壁，塵粒一旦與器壁接觸，便失去慣性力而靠入口速度的動量和自身的重力沿壁面下落進(jìn)入集灰斗。旋轉(zhuǎn)下降的氣流在到達(dá)圓錐體底部后沿除塵器的軸心部位轉(zhuǎn)而向上形成上升的內(nèi)旋氣流，并由除塵器的排氣管排出。 自進(jìn)氣口流人的另一小部分氣流，則向旋風(fēng)除塵器頂蓋處流動，然后沿排氣管外側(cè)向下流動，當(dāng)達(dá)到排氣管下端時(shí)，即反轉(zhuǎn)向上隨上升的中心氣流一同從誹氣管排出，分散在其中的塵粒也隨同被帶走。3.2用途及適用范圍旋風(fēng)除塵器主要用于工業(yè)生產(chǎn)中清除工業(yè)廢料，如木料廠以及其他工廠。在我國大多數(shù)工廠都是使用旋風(fēng)除塵器。3.3產(chǎn)品描述旋風(fēng)除塵器是一種常見的氣固，氣液和液固分離設(shè)備。由于結(jié)構(gòu)簡單，造價(jià)低廉，操作簡便，運(yùn)行穩(wěn)定等特點(diǎn)，旋風(fēng)除塵器在機(jī)械，建材，輕工，冶金，化工，石油等行業(yè)得到廣泛應(yīng)用。理論與實(shí)驗(yàn)研究均以證明，旋風(fēng)除塵器的動力消耗中有相當(dāng)大一部分無益于分離，屬純消耗性能量損失。四.設(shè)計(jì)方案的擬定4.1旋風(fēng)除塵器的原理分析 旋風(fēng)除塵器的工作原理主要是靠慣性離心力的作用，使粉塵與含塵空氣分開。塵粒受到的離心力為： 式中：p塵粒的密度 d塵粒的直徑 v含塵空氣的進(jìn)口風(fēng)速 R旋風(fēng)除塵器的圓筒體半徑由上式可知：離心力的大小與進(jìn)口氣流速度，旋風(fēng)除塵器的直徑及塵粒的密度，直徑有關(guān)。所以我們說影響除塵效率的因素由以下幾方面決定。1. 進(jìn)口氣流速度一般來說，進(jìn)口氣流速度越大，塵粒受到的離心力越大，除塵效率越高。同時(shí)處理含塵空氣氣量也夜多。但實(shí)踐證明：進(jìn)口氣流速度越大時(shí)，不但除塵效率不高，反而會下降。這是因?yàn)椋寒?dāng)風(fēng)速過大時(shí)，會把原來已除下來的塵粒重新帶跑，形成返混現(xiàn)象。同時(shí)由于進(jìn)口氣流的增加會使阻力急劇增加，從而使電耗急劇增加。這是因?yàn)椋枇ο呐c風(fēng)速的二次方成正比例關(guān)系，所以進(jìn)口風(fēng)速一般控制在12-18米/秒之間。2. 旋風(fēng)除塵器筒體的直徑和排風(fēng)管的直徑在其它條件不變的情況下，減小筒體直徑，塵粒所受到的離心力也增大，所以應(yīng)采用小直徑的旋風(fēng)除塵器（排風(fēng)管直徑為筒體的直徑的0.5-0.6倍）。一般不超過800毫米。但直徑小了，處理風(fēng)量少，可以采用幾個(gè)餓旋風(fēng)除塵器并聯(lián)使用。處理風(fēng)量為各除塵器風(fēng)量之和，阻力為單個(gè)除塵器的阻力。3. 筒體高度和錐體高度筒體高度和錐體高度越高，含塵空氣分離的時(shí)間越長，除塵效果越好。但過高了下部也不起作用。由于錐體部分的直徑逐漸減少，其除塵效率高于通體部分建議采用短筒體長錐體。錐體部分的高度一般為筒體部分的2-3倍為宜。4. 底部的密封性由于旋風(fēng)除塵器工作時(shí)，底部和中心部位是負(fù)壓力不從心，所以底部是否漏風(fēng)是影響除塵效率的關(guān)鍵因素。實(shí)踐證明，當(dāng)?shù)撞柯╋L(fēng)率為5%時(shí)，除塵效率下降50%；當(dāng)?shù)撞柯╋L(fēng)率10%時(shí)，除塵效率幾乎為零。當(dāng)?shù)撞慷ㄆ谇寤視r(shí)，可將出灰口與密閉灰箱相連；當(dāng)連續(xù)清灰時(shí)，要安裝閉風(fēng)器，并且閉風(fēng)器的膠皮與殼體密封，轉(zhuǎn)速要慢。針對不少工廠，采用的旋風(fēng)除塵器直徑偏大，除塵效果不好的現(xiàn)狀。根據(jù)以上分析，結(jié)合各廠的實(shí)際情況，針對旋風(fēng)除塵器提出以下改進(jìn)意見，僅供參考。1.）旋風(fēng)除塵器的直徑改為300-400毫米，每四個(gè)一組，下部供用一個(gè)密閉的集塵箱。每一個(gè)除塵管網(wǎng)，根據(jù)所需處理的含塵空氣量的多少，確定需要多少組旋風(fēng)除塵器。各組除塵器均并聯(lián)使用。 2.旋風(fēng)除塵器采用下旋型，可以避免上渦旋的形成，提高除塵效率。 3.旋風(fēng)除塵器的筒體高度為0.5米左右，錐體部分的高度為1米左右。采用短筒體長錐體的設(shè)計(jì)。 4.旋風(fēng)除塵器進(jìn)口風(fēng)速一般控制在12-16米/秒左右，不宜過大，否則會使阻力增加，增加電耗。 5.設(shè)計(jì)制造旋風(fēng)除塵器時(shí)，要保證質(zhì)量，從排風(fēng)管中心到下部錐體中心，要成鉛垂線，以免影響分離粉粒及排風(fēng)曲線，影響除塵效率。 6.注意底部的密封性。定期清灰時(shí)，注意下部留有一定的灰封。連續(xù)清灰時(shí)，閉風(fēng)器的轉(zhuǎn)速要慢。膠皮不能脫落，并要與殼體相接觸。 4.2 旋風(fēng)除塵器進(jìn)氣量的計(jì)算： G=0.06 x V x n x Y x r x K (噸 /小時(shí) ) 式中： V一旋風(fēng)器容積（升/轉(zhuǎn)） n一旋風(fēng)器轉(zhuǎn)速（轉(zhuǎn)分） Y一旋風(fēng)器容積效率：顆粒狀物料0.7-0.8 粉狀物料0.5-0.6 r一物料容重（噸米3） K一修正系數(shù)，一般取0.7-0.8 說明書數(shù)據(jù)表2：物料容重 r(噸/立方米) 容積（升/轉(zhuǎn)）V 葉輪半徑（毫米）R葉輪長度（毫米）l轉(zhuǎn)速(轉(zhuǎn)/分) n動力(千瓦) w 2.4810150250350.75/1.1粉狀物料的容積效率Y=0.6修正系數(shù) K=0.8旋風(fēng)器進(jìn)氣量的計(jì)算： G=0.06xVxnxYxrxK =0.06100.00135600.62.480.8 =1.5(噸/時(shí))4.3 旋風(fēng)除塵器內(nèi)的流場分析 （1）流場組成外渦旋沿外壁由上向下旋轉(zhuǎn)運(yùn)動的氣流。內(nèi)渦旋沿軸心向上旋轉(zhuǎn)運(yùn)動的氣流。渦流由軸向速度與徑向速度相互作用形成的渦流。包括上渦流旋風(fēng)除塵器頂蓋，排氣管外面與筒體內(nèi)壁之間形成的局部渦流，它可降低除塵效率；下渦流在除塵器縱向，外層及底部形成的局部渦流。（2）旋風(fēng)除塵器內(nèi)氣流與塵粒的運(yùn)動含塵氣流由切線進(jìn)口進(jìn)入除塵器，沿外壁由上向下作螺旋形旋轉(zhuǎn)運(yùn)動，這股向下旋轉(zhuǎn)的氣流即為外渦旋。外渦旋到達(dá)錐體底部后，轉(zhuǎn)而向上，沿軸心向上旋轉(zhuǎn)，最后經(jīng)排出管排出。這股向上旋轉(zhuǎn)的氣流即為內(nèi)渦旋。向下的外渦旋和向上的內(nèi)渦旋，兩者的旋轉(zhuǎn)方向是相同的。氣流作旋轉(zhuǎn)運(yùn)動時(shí)，塵粒在慣性離心力的推動下，要向外壁移動。到達(dá)外壁的塵粒在氣流和重力的共同作用下，沿壁面落入灰斗。氣流從除塵器頂部向下高速旋轉(zhuǎn)時(shí)，頂部的壓力發(fā)生下降，一部分氣流會帶著細(xì)小的塵粒沿外壁旋轉(zhuǎn)向上，到達(dá)頂部后，再沿排出管外壁旋轉(zhuǎn)向下，從排出管排出。這股旋轉(zhuǎn)氣流即為上渦旋。如果除塵器進(jìn)口和頂蓋之間保持一定距離，沒有進(jìn)口氣流干擾，上渦旋表現(xiàn)比較明顯。對旋風(fēng)除塵器內(nèi)氣流運(yùn)動的測定發(fā)現(xiàn)，實(shí)際的氣流運(yùn)動是很復(fù)雜的。除切向和軸向運(yùn)動外還有徑向運(yùn)動。特林頓（T.Linden）在測定中發(fā)現(xiàn)，外渦旋的徑向速度是向心的，內(nèi)渦旋的徑向速度是向外的，速度分布呈對稱型。 （3）切向速度切向速度是決定氣流速度大小的主要速度分量，也是決定氣流中質(zhì)點(diǎn)離心力大小的主要因素。切向速度的變化規(guī)律為：外渦旋區(qū)：r，切向速度ut；內(nèi)渦旋區(qū)：r，切向速度ut。 圖 3 所示為實(shí)測的除塵器某一斷面上的速度分布和壓力分布。 從該圖可以看出，外渦旋的切向速度 是隨半徑r的減小而增加的，在內(nèi)、外渦旋交界面上， 達(dá)到最大?？梢越普J(rèn)為，內(nèi)外渦旋交界面的半徑r0（0.60.65）rp（rp為排出管半徑）。內(nèi)渦旋的切向速度是隨r的減小而減小的，類似于剛體的旋轉(zhuǎn)運(yùn)動。旋風(fēng)除塵器內(nèi)某一斷面上的切向速度分布規(guī)律可用下式表示：外渦旋 vr1/nr=c （4-3-1） 內(nèi)渦旋 vt/r=c （4-3-2） 式中 vt切向速度；圖3旋風(fēng)除塵器內(nèi)部的速度分布和壓力分布r距軸心的距離；c、c、n常數(shù)，通過實(shí)測確定。一般n=0.50.8，如果近似的取n=0.5，公式（4-3-1）可以改寫為 （4-3-3）（4）徑向速度實(shí)測表明，旋風(fēng)除塵器內(nèi)的氣流除了作切向運(yùn)動外，還要作徑向的運(yùn)動，外渦旋的徑向速度是向心的，而內(nèi)渦旋的徑向速度是向外的。氣流的切向分速度vt和徑向分速度w對塵粒的分離起著相反的影響，前者產(chǎn)生慣性離心力，使塵粒有向外的徑向運(yùn)動，后者則造成塵粒作向心的徑向運(yùn)動，把它推入內(nèi)渦旋。 如果近似認(rèn)為外渦旋氣流均勻地經(jīng)過內(nèi)、外渦旋交界面進(jìn)入內(nèi)渦旋，見圖5-4-3所示，那末在交界面上氣流的平均徑向速度 （4-3-5）式中 L旋風(fēng)除塵器處理風(fēng)量，m3/s；H假想圓柱面（交界面）面度，m；r0交界面的半徑，m。（5）軸向速度外渦旋的軸向速度向下，內(nèi)渦旋的軸向速度向上。在內(nèi)渦旋，隨氣流逐漸上升，軸向速度不斷增大，在排氣管底部達(dá)到最大值。（6）壓力分布壓力分布：軸向壓力變化較??；徑向壓力變化大，外側(cè)高，中心低，軸心處為負(fù)壓。旋風(fēng)除塵器內(nèi)軸向各斷面上的速度分布差別較小，因此軸向壓力的變化較小。從圖5-4-20可以看出，切向速度在徑向有很大變化，因此徑向的壓力變化很大（主要是靜壓），外側(cè)高中心低。這是因?yàn)闅饬髟谛L(fēng)除塵器內(nèi)作圓周運(yùn)動時(shí)，要有一個(gè) 圖4交界面上氣流的徑向速度 向心力與離心力相平衡，所以外側(cè)的壓力要比內(nèi)側(cè)高。在外壁附近靜壓最高，軸心處靜壓最低。試驗(yàn)研究表明，即使在正壓下運(yùn)行，旋風(fēng)除塵器軸心處也保持負(fù)壓，這種負(fù)壓能一直延伸到灰斗。據(jù)測定，有的旋風(fēng)除塵器當(dāng)進(jìn)口處靜壓為+900Pa時(shí)，除塵器下部靜壓為300Pa。因此，除塵器下部不保持嚴(yán)密，會有空氣滲入，把已分離的粉塵重新卷入內(nèi)渦旋。五.零部件的數(shù)據(jù)計(jì)算及選擇5.1 風(fēng)機(jī)的分析與選擇： 風(fēng)機(jī)產(chǎn)品分為兩大類，一類是重要裝置中的高精尖產(chǎn)品，主要指透平壓縮機(jī)。另一類是量大面廣的中，小通風(fēng)機(jī)。 風(fēng)機(jī)行業(yè)國內(nèi)外的發(fā)展趨勢是（1）大型風(fēng)機(jī)容量繼續(xù)增大。（2）發(fā)展高壓小流量壓縮機(jī)。（3）高效化。（4）高速小型化。（5）低噪聲化。（6）計(jì)算機(jī)集成制造系統(tǒng)在風(fēng)機(jī)中得以廣泛應(yīng)用。 本設(shè)計(jì)采用的風(fēng)機(jī)是離心式鼓風(fēng)機(jī)。 5.2 下料箱的選擇： 下料箱是粉狀物料提升輸送裝置中一個(gè)重要部件。工程上一般要求該部件在負(fù)壓差下工作 ,即將物料由壓力較低處送往壓力相對較高處。在工作過程中 ,要求對通過的物料量具有良好的調(diào)節(jié)性能 ,并且保證它所連接的兩器氣體互相不泄漏。從而保證輸送能正常與高效地工作。因此在下料箱結(jié)構(gòu)的設(shè)計(jì)中，能否有效地解決下料箱的防堵性與氣密性，是防止下料箱被物料堵塞以及順利排料的關(guān)鍵。 全新氣封式葉輪下料箱適用干將壓力狀態(tài)下的粉狀或顆粒狀物料連續(xù)地、順利地排入大氣，是氣力輸送和通風(fēng)除塵網(wǎng)路中的一種重要設(shè)備。其主要工作件是旋轉(zhuǎn)的葉輪，既起著輸送物料的作用，又擔(dān)負(fù)著密封作用。使用安全可靠，體積小、重量輕、 容量大、 功率消耗低等特點(diǎn)。廣泛用于糧食、食品、飼料、油脂、化工、儲運(yùn)及其它工業(yè)中的氣力輸送或通風(fēng)除塵網(wǎng)路卸料器之排料、排塵。 采用國內(nèi)外最先進(jìn)卸料器特點(diǎn)，又集中國內(nèi)外各種干燥機(jī)、除塵器聯(lián)接尺寸而設(shè)計(jì)制造的，它三機(jī)一體，結(jié)構(gòu)緊湊、密封性好、運(yùn)轉(zhuǎn)平穩(wěn)、造型美觀、噪音低、體積小、重量輕、使用方便等特點(diǎn)，是氣力輸送、自動計(jì)量排料重要設(shè)備之一。5.3殼體的設(shè)計(jì)： 這類零件的內(nèi)外結(jié)構(gòu)都很復(fù)雜,它是用來支撐、包容運(yùn)動零件或其它零件,因此其內(nèi)部常有空腔.箱體內(nèi)腔常用來安裝傳動軸、齒輪(或葉輪)及滾動軸承等,故兩端均有裝軸承蓋及套的孔.所以箱體的蓋、座上有許多安裝孔、定位銷孔、連接孔;由于箱體是空腔的,通常壁比較薄,由于形狀復(fù)雜,箱體多為鑄件旋風(fēng)器中的箱體材料可以選 HT150。 殼體的整體壁厚為10mm，殼體分為筒體和錐體兩部分。筒體的內(nèi)腔直徑與葉輪的大徑相等，螺栓連接的邊緣寬度為30mm，進(jìn)料口的最大長度為415mm，寬度為360mm，其小徑為3/2的葉輪扇形寬度。即：Q=190(mm)5.4 密封圈的設(shè)計(jì) 為了減小設(shè)計(jì)和制造裝配過程中的誤差引起的漏風(fēng)量，要在殼體端蓋和殼體之間設(shè)計(jì)一個(gè)密封圈，主要起到密封作用，不受其他外力，可以選用橡膠材料，密封圈的內(nèi)徑要少小于殼體的內(nèi)徑，可以確定為298mm,厚度和寬度也都不需設(shè)計(jì)很大，可以確定為6mm和10mm。一半嵌在殼體端蓋一半嵌在殼體端邊。5.5殼體端蓋的設(shè)計(jì) 殼體的端蓋起著多方面的作用，可以密封防漏氣支撐軸承.軸承工作過程中內(nèi)圓隨軸轉(zhuǎn)動，外圈保持不動，則軸承的外圓與殼體之間的配合為過盈配合，那么端蓋的內(nèi)徑就可以確定為61mm,考慮到與殼體的配合，可把外徑確定為360mm等于殼體的最外圓的直徑。在殼體的內(nèi)面設(shè)計(jì)一個(gè)小槽，用來配合密封圈，小槽的寬度與密封圈的厚度相等為6mm，深度是密封圈寬度的一半為5mm.。5.6 其他標(biāo)準(zhǔn)連接件的選擇任何機(jī)器都是由各種零件組成,其中標(biāo)準(zhǔn)件占有大量的比例,它們以一定的形式連接,保持相互之間的位置和按一定的規(guī)律相對運(yùn)動,標(biāo)準(zhǔn)件可以互換通用,從而提高經(jīng)濟(jì)效率.常用的標(biāo)準(zhǔn)件有緊固件(螺栓、螺母、螺釘)、鍵等. 5.6.1 螺栓的選擇 螺紋規(guī)格(6g)|d: M12螺紋規(guī)格(6g)|dP: M121.5b(參考)|l125: 30B(參考)|125l200: 36e min: 20.03s|max: 18s|min|: 17.73k 公稱: 7.5l長度范圍|: 45120 圖75.6.2 沉頭螺釘?shù)倪x擇： 由于軸承蓋是與殼體的端蓋連接在一起的，屬于內(nèi)部連接所以要選用沉頭螺釘。 螺釘螺紋規(guī)格: ST2.2螺距P=a(max): 0.8dk(max): 3.8k(max): 1.1十字槽|槽號: 0十字槽|H型插入深度|max: 1.2l長度范圍: 4.516表面處理: 鍍鋅鈍化 圖8機(jī)械設(shè)計(jì)手冊5.6.3 螺母的選擇： 其內(nèi)徑與螺栓的d相等為12mm，可以查機(jī)械設(shè)計(jì)手冊如下： 螺母螺紋規(guī)格(6H)|D: M12螺紋規(guī)格(6H)|DP: M121.5 (M121.25)e/min: 20.03s/max: 18s/min: 17.73m/max: 10.8圖95.6.4 鍵的選擇： 根據(jù)鍵連接的軸的軸徑，查閱機(jī)械設(shè)計(jì)手冊可以得到標(biāo)準(zhǔn)鍵為：軸徑 d: 3038鍵的公稱尺寸|b(h8): 10鍵的公稱尺寸|(h8)h(11): 8鍵的公稱尺寸|c或r: 0.40.6鍵的公稱尺寸|L（h14）: 22110鍵槽|軸槽深t|基本尺寸: 5.0鍵槽|軸槽深t|公差: (+0.2,0)鍵槽|轂槽深t1|基本尺寸: 3.3鍵槽|轂槽深t1|公差: (+0.2,0)鍵槽|圓角半徑r|min: 0.25鍵槽|圓角半徑r|max: 0.4 圖10六.旋風(fēng)除塵器的改進(jìn)和開發(fā)6.1 旋風(fēng)除塵器的工作原理主要是靠慣性離心力的作用，使粉塵與含塵空氣分開。塵粒受到的離心力為： 由上式可知：離心力的大小與進(jìn)口氣流速度，旋風(fēng)除塵器的直徑及塵粒的密度，直徑有關(guān)。所以我們說影響除塵效率的因素由以下幾方面決定。1. 進(jìn)口氣流速度一般來說，進(jìn)口氣流速度越大，塵粒受到的離心力越大，除塵效率越高。同時(shí)處理含塵空氣氣量也夜多。但實(shí)踐證明：進(jìn)口氣流速度越大時(shí)，不但除塵效率不高，反而會下降。這是因?yàn)椋寒?dāng)風(fēng)速過大時(shí)，會把原來已除下來的塵粒重新帶跑，形成返混現(xiàn)象。同時(shí)由于進(jìn)口氣流的增加會使阻力急劇增加，從而使電耗急劇增加。這是因?yàn)?，阻力消耗與風(fēng)速的二次方成正比例關(guān)系，所以進(jìn)口風(fēng)速一般控制在12-18米/秒之間。2. 旋風(fēng)除塵器筒體的直徑和排風(fēng)管的直徑在其它條件不變的情況下，減小筒體直徑，塵粒所受到的離心力也增大，所以應(yīng)采用小直徑的旋風(fēng)除塵器（排風(fēng)管直徑為筒體的直徑的0.5-0.6倍）。一般不超過800毫米。但直徑小了，處理風(fēng)量少，可以采用幾個(gè)餓旋風(fēng)除塵器并聯(lián)使用。處理風(fēng)量為各除塵器風(fēng)量之和，阻力為單個(gè)除塵器的阻力。3. 筒體高度和錐體高度筒體高度和錐體高度越高，含塵空氣分離的時(shí)間越長，除塵效果越好。但過高了下部也不起作用。由于錐體部分的直徑逐漸減少，其除塵效率高于通體部分建議采用短筒體長錐體。錐體部分的高度一般為筒體部分的2-3倍為宜。4. 底部的密封性由于旋風(fēng)除塵器工作時(shí)，底部和中心部位是負(fù)壓力不從心，所以底部是否漏風(fēng)是影響除塵效率的關(guān)鍵因素。實(shí)踐證明，當(dāng)?shù)撞柯╋L(fēng)率為5%時(shí)，除塵效率下降50%；當(dāng)?shù)撞柯╋L(fēng)率10%時(shí)，除塵效率幾乎為零。當(dāng)?shù)撞慷ㄆ谇寤視r(shí)，可將出灰口與密閉灰箱相連；當(dāng)連續(xù)清灰時(shí)，要安裝閉風(fēng)器，并且閉風(fēng)器的膠皮與殼體密封，轉(zhuǎn)速要慢。針對不少工廠，采用的旋風(fēng)除塵器直徑偏大，除塵效果不好的現(xiàn)狀。根據(jù)以上分析，結(jié)合各廠的實(shí)際情況，針對旋風(fēng)除塵器提出以下改進(jìn)意見，僅供參考。1.）旋風(fēng)除塵器的直徑改為300-400毫米，每四個(gè)一組，下部供用一個(gè)密閉的集塵箱。每一個(gè)除塵管網(wǎng)，根據(jù)所需處理的含塵空氣量的多少，確定需要多少組旋風(fēng)除塵器。各組除塵器均并聯(lián)使用。 2.旋風(fēng)除塵器采用下旋型，可以避免上渦旋的形成，提高除塵效率。 3.旋風(fēng)除塵器的筒體高度為0.5米左右，錐體部分的高度為1米左右。采用短筒體長錐體的設(shè)計(jì)。 4.旋風(fēng)除塵器進(jìn)口風(fēng)速一般控制在12-16米/秒左右，不宜過大，否則會使阻力增加，增加電耗。 5.設(shè)計(jì)制造旋風(fēng)除塵器時(shí)，要保證質(zhì)量，從排風(fēng)管中心到下部錐體中心，要成鉛垂線，以免影響分離粉粒及排風(fēng)曲線，影響除塵效率。 6.注意底部的密封性。定期清灰時(shí)，注意下部留有一定的灰封。連續(xù)清灰時(shí)，閉風(fēng)器的轉(zhuǎn)速要慢。膠皮不能脫落，并要與殼體相接觸。 以上改進(jìn)，經(jīng)幾個(gè)廠家使用，效果良好，整齊美觀，除塵效率基本能達(dá)到國家規(guī)定的標(biāo)準(zhǔn)。6.2旋風(fēng)除塵器的類型： 旋風(fēng)除塵器又名（Cyclone直譯）。它是利用旋轉(zhuǎn)的含塵氣體所產(chǎn)生的離心力，將粉塵從氣流中分離出來的一種干式氣-固二相留分離裝置。旋風(fēng)除塵器用于工業(yè)生產(chǎn)，已有百余年歷史。由于它結(jié)構(gòu)簡單，無運(yùn)動部件，制造安裝投資少，操作維護(hù)簡便，性能穩(wěn)定，受含塵氣體的濃度和溫度影響較少，壓損中等，動力消耗不大，所以廣泛用于各種工藝過程中。隨著旋風(fēng)除塵器的使用日益廣泛，人們對旋風(fēng)除塵器內(nèi)部的氣流狀態(tài)與固體顆粒的運(yùn)動規(guī)律做過大量的研究，結(jié)構(gòu)改進(jìn)取得不少進(jìn)步，研制出許多性能良好的旋風(fēng)除塵器。按氣流導(dǎo)入情況，旋風(fēng)除塵器可分為2類：1) 切流反轉(zhuǎn)式旋風(fēng)除塵器這是旋風(fēng)除塵器的形式。如圖11a b c含塵氣體由筒體的側(cè)面沿切線方向?qū)?。氣流在圓筒部旋轉(zhuǎn)向下，進(jìn)入錐體，到達(dá)錐體的端點(diǎn)反轉(zhuǎn)向上，清潔氣流經(jīng)排氣管排出口。這類旋風(fēng)除塵器根據(jù)不同的進(jìn)口形式，又可分為圖11.a蝸殼進(jìn)口，圖11.b蝸旋進(jìn)口，圖11.c長方形切線進(jìn)口。以上三種進(jìn)口是目前常見的形式，已由上世紀(jì)50年代應(yīng)用至今。為了提高除塵器的捕集效率，把排出氣體中含塵濃度高的氣體一二次風(fēng)形式引出后，經(jīng)風(fēng)機(jī)再導(dǎo)入旋風(fēng)分離器內(nèi)。這種旋風(fēng)除塵器，按二次風(fēng)因入方式可分為：圖12.d切流二次風(fēng)和圖12.e軸流二次風(fēng)。圖11圖122）錐體彎曲的水平旋風(fēng)除塵器 可節(jié)省占地面積，簡化管路系統(tǒng)。進(jìn)口速度較大時(shí)，除塵效率與立式的相差不大。主要用于中小型鍋爐的煙氣除塵。3）擴(kuò)散式旋風(fēng)除塵器 它是一種具有呈倒錐體形狀的錐體，并在錐體的底部裝有反射屏的旋風(fēng)除塵器。反射屏可防止上升氣流卷起粉塵，從而提高除塵效率。4） 旋風(fēng)慣性除塵器旋風(fēng)慣性除塵器是普通旋風(fēng)除塵器和百葉式慣性除塵器的組合,兼有慣性和旋風(fēng)除塵功能。旋風(fēng)慣性除塵器的結(jié)構(gòu)如圖15。含塵氣體從頂部螺旋線進(jìn)口切向進(jìn)入筒體,粉塵因離心力被甩向外筒內(nèi)壁,隨外螺線下降氣流落入錐斗。還有部分細(xì)小粉塵在靠近百葉窗碰撞反彈隨氣流下降至錐斗。此外,因?yàn)橥ㄟ^百葉窗間隙提前排除大部分凈化氣流,從而減少了錐體尾部返混二次氣流量,有利于除塵效率的提高,降低了壓力損失。旋風(fēng)慣性除塵器壓力損失小,處理風(fēng)量大,適用于凈化非纖維狀的粉塵,和在初始粉塵含量大的場合,作為二級除塵的一級凈化。 圖136.3 旋風(fēng)除塵器的進(jìn)口形式 目前常用的進(jìn)口形式有直入式、蝸殼式和軸流式三種，見圖14所示，直入式又分為平頂蓋和螺旋形頂蓋。平頂蓋直入式進(jìn)口結(jié)構(gòu)簡單，應(yīng)用最為廣泛。螺旋形直入式進(jìn)口避免了進(jìn)口氣流與旋轉(zhuǎn)氣流之的干擾，可減小阻力，但效率會下降。如果除塵器處理風(fēng)量大，需要大的進(jìn)口，采用蝸殼式進(jìn)口可以避免進(jìn)口氣流與排出管發(fā)生直接碰撞（見圖15），有利于除塵效率和阻力的改善。軸流式進(jìn)口主要用于多管旋風(fēng)除塵器的旋風(fēng)子。 圖14 旋風(fēng)除塵器的進(jìn)口形式 圖15 蝸殼式進(jìn)口形式 6.4 排灰裝置 旋風(fēng)除塵器下部出現(xiàn)漏風(fēng)時(shí)，效率會顯著下降。如何在不漏風(fēng)的情況下進(jìn)行正常排灰是旋風(fēng)除塵器運(yùn)行中必須重視的一個(gè)問題。收塵量不大的除塵器，可在下部設(shè)固定灰斗，定期排除。收塵量較大，要求連續(xù)排灰時(shí)，可設(shè)雙翻板式和回轉(zhuǎn)式鎖氣器。翻板式鎖氣器是利用翻板上的平衡錘和積灰質(zhì)量的平衡發(fā)生變化時(shí)，進(jìn)行自動卸灰的。它設(shè)有兩塊翻板輪流啟閉，可以避免漏風(fēng)?；剞D(zhuǎn)式鎖氣器采用外來動力使刮板緩慢旋轉(zhuǎn)，轉(zhuǎn)速一般在1520rmin之間，它適用于排灰量較大的除塵器。回轉(zhuǎn)式鎖氣器能否保持嚴(yán)密，關(guān)鍵在于刮板和外殼之間緊密貼合的程度。6.5 旋風(fēng)除塵器操作條件旋風(fēng)除塵器的性能好壞,除與以上結(jié)構(gòu)尺寸有關(guān)外,還取決于操作條件。第一,要正確的熟悉各種旋風(fēng)除塵器性能,選用合理的進(jìn)口風(fēng)速和處理量,進(jìn)口風(fēng)速一般范圍在1025m/s。第二,特殊場合還要考慮到氣體密度,大氣壓和溫度的變化,及時(shí)修正實(shí)際處理量,進(jìn)口風(fēng)速及壓力變化。第三,粉塵的物理性質(zhì),要考慮二相流中粉塵的密度、粒度分布,粉塵的濕度、粘性和是否有纖維狀或絨毛狀粉塵等,合理選用除塵器。影響旋風(fēng)除塵器的性能因素,除上述原因外,除塵器的內(nèi)壁是否光滑,焊縫是否磨光,聯(lián)接法蘭是否有內(nèi)突出物等等都會引起旋轉(zhuǎn)氣流擾動,影響除塵效率。因此應(yīng)當(dāng)重視除塵器的制造質(zhì)量。19第 1 頁 共 12 頁 Multi cyclone dust collector for a vacuum cleaner1.Background of the invention1. 1 Field of the InventionThe present invention relates to a vacuum cleaner. More particularly, the presentinvention relates to a multi-cyclone dust collector for a vacuum cleaner that separates andcollects contaminants from sucked air by centrifugal force.1.2 Description of the Related ArtA cyclone type vacuum cleaner, which separates contaminants from sucked air bycentrifugal force, employs a cyclone dust collector providing semi permanent use. Because a cyclone type vacuum cleaner is more sanitary and convenient than a vacuum cleaneremploying a dust bag or a dust filter, cyclone type vacuum cleaners have become widespread.An example of a conventional cyclone dust collector is shown in FIG. 1. Referring to FIG.1, the conventional cyclone dust collector 500 includes a cylindrical cyclone body 510 inwhich sucked air containing contaminants forms a whirling current therein, an air inlet 520through which the air containing contaminants enters, and an air outlet 530 through whichclean air is discharged. The air inlet 520 is disposed at a side of an upper portion of thecyclone body 510 in a tangential direction relative to the cyclone body 510 so that the airentering the cyclone body 510 whirls downward easily. The air outlet 530 is disposed at acenter of a top surface of the cyclone body 510 so that the air, which has contaminants removed as the air whirls downwardly, then rises up inside the cyclone body 510, and isdischarged out of the cyclone dust collector 500. Separated contaminants are discharged in thegravity direction through a contaminants outlet 540 that is formed at a lower portion of thecyclone body 510. 第 2 頁 共 12 頁 However, in the conventional cyclone dust collector 500, the air whirling downwardlycollides with the air rising up inside the cyclone body 510 because both the air inlet 520 andthe air outlet 530 are disposed at the upper portion of the cyclone body 510. Accordingly, theconventional cyclone dust collector 500 has a problem that a dust collecting efficiency thereofis decreased due to collision between the rising air and the descending air.Currently, a multi-cyclone dust collector has been developed and has become widespread.The multi-cyclone dust collector separates contaminants from air in two or more stages, andespecially provides a plurality of cyclones for separating fine contaminants. An example of aconventional multi-cyclone dust collector 600 is shown in FIG. 2. Referring to FIG. 2, the conventional multi-cyclone dust collector 600 includes a firstcyclone 610 that centrifugally separates contaminants from sucked air, and a plurality ofsecond cyclones 620 that sucks the air being discharged from the first cyclone 610, and then,separates fine contaminants remaining in the air. First and second air inlets 611 and 621through which air is sucked into the first and second cyclone 610 and 620, and first and secondair outlets 612 and 622 through which air having contaminants removed is discharged aredisposed at upper portions of the first and second cyclones 610 and 620. Accordingly, airhaving contaminants removed is discharged in a direction opposite to the gravity direction.Also, first and second dust receptacles 613 and 623 are formed under the first and secondcyclones 610 and 620. Therefore, contaminants that are separated in the first and second cyclones 610 and 620 are discharged in the gravity direction, and then are collected in the firstand second receptacles 613 and 623, respectively.Because the first and second receptacles 613 and 623 are not isolated from the first andsecond cyclones 610 and 620 in which air forms whirling currents, contaminants that arecollected in the first and second receptacles 613 and 623 are re-scattered and flow back due tothe whirling current. The backflow of contaminants decreases the dust collecting efficiency of 第 3 頁 共 12 頁 the cyclone dust collector 600 and shortens the filter maintenance cycle of the cyclone dustcollector 600.Furthermore, the multi-cyclone dust collector 600 still has the problem that air collisionoccurs so as to decrease the dust collecting efficiency as described above, because the airinlets 611 and 621 and the air outlets 612 and 622 are disposed at the upper portions of thefirst and second cyclones 610 and 620.Furthermore, the conventional multi-cyclone dust collector 600 has a drawback that theheight thereof is high, because the space in which the air whirls and the space in whichcontaminants are collected are arranged vertically. Accordingly, there is a need for an improved multi-cyclone dust collector the height ofwhich is lower and is more compact as compared of the conventional multi-cyclone dustcollector.2.Summary of the inventionThe present invention has been developed in order to overcome the above drawbacks andother problems associated with the conventional arrangement. An object of the presentinvention is to provide a multi-cyclone dust collector for a vacuum cleaner that has a high dustcollecting efficiency because air collision does not occur inside a cyclone.Another object of the present invention is to provide a multi-cyclone dust collector that has a high dust collecting efficiency and a long filter maintenance cycle because collectedcontaminants are not re-scattered.Still another object of the present invention is to provide a compact multi-cyclone dustcollector having a space in which contaminants are collected disposed at a side of a space inwhich air whirls. 第 4 頁 共 12 頁 Yet another object of the present invention is to provide a multi-cyclone dust collector fora vacuum cleaner having a configuration where a volume of a first dust collecting chamber islarger than a volume of a second dust collecting chamber.The above objects and/or other features of the present invention can substantially beachieved by providing a multi-cyclone dust collector for a vacuum cleaner, which includes atleast one first cyclone forcing outside air that is entered into a lower portion of the at least onefirst cyclone to whirl so as to centrifugally separate contaminants from the outside air; and atleast one second cyclone being disposed around the at least one first cyclone, the at least onesecond cyclone forcing air that is discharged from the at least one first cyclone to enter into alower portion of the at least one second cyclone to whirl so as to centrifugally separate contaminants from the air.The at least one second cyclone is smaller in size than the at least one first cyclone. Theat least one first cyclone and the at least one second cyclone discharge air in the gravitydirection. The gravity direction means the direction in which the earths gravity operates.Also, a place through which air is discharged from the at least one first cyclone and asecond place through which air enters the at least one second cyclone are on the same plane.And the at least one first cyclone discharges the contaminants in a direction opposite to thegravity direction.According to an embodiment of the present invention, multi-cyclone dust collector further includes a first dust collecting chamber being disposed around the at least one firstcyclone, and collecting the contaminants discharged from the at least one first cyclone. The atleast one second cyclone is disposed inside the first dust collecting chamber. A height of the atleast one first cyclone is lower than a height of the first dust collecting chamber.According to an embodiment of the present invention, in each of the at least one firstcyclone and the at least one second cyclone, a place through which contaminants are 第 5 頁 共 12 頁 discharged is higher than a place through which air enters. And, a place through whichcontaminants are discharged is higher than a place through which air is discharged.According to an embodiment of the present invention, the at least one second cyclonedischarges the contaminants in a direction opposite to the gravity direction.According to an embodiment of the present invention, the multi-cyclone dust collectorfurther includes a second dust collecting chamber being disposed at a side of the at least onesecond cyclone, and collecting the contaminants discharged from the at least one secondcyclone.According to an embodiment of the present invention, the multi-cyclone dust collector includes: a plurality of second cyclones; and a plurality of second dust collecting chamberswrapping around at least one of the second cyclones, and collecting contaminants dischargedfrom at least one of the second cyclones.According to an embodiment of the present invention, the second dust collecting chamberis formed to wrap around two nearby second cyclones so as to collect contaminants dischargedfrom the two nearby second cyclones.According to an embodiment of the present invention, the second dust collecting chamberwraps around all the plurality of second cyclones so as to collect contaminants dischargedfrom the plurality of second cyclones. According to an embodiment of the present invention, some part of the at least one firstcyclone forms some part of the at least one second cyclone.According to an embodiment of the present invention, the at least one second cyclone isin a substantially conical shape, and some part of the first cyclone forms a side surface of thelower portion of the at least one second cyclone. 第 6 頁 共 12 頁 According to another aspect of the present invention, a multi-cyclone dust collector for avacuum cleaner includes: a first cyclone sucking outside air into a lower portion of the firstcyclone, forcing the outside air to form a first upwardly whirling air current so as tocentrifugally separate contaminants from the outside air; a first dust collecting chamber beingdisposed to wrap around some of the first cyclone, collecting the contaminants dischargedfrom the first cyclone; and a plurality of second cyclones being disposed around the firstcyclone, sucking air that is discharged from the first cyclone into a lower portion of each ofthe second cyclones, forcing the air to form a second upwardly whirling air current so as tocentrifugally separate contaminants from the air.According to an embodiment of the present invention, the first cyclones includes a first cyclone body having a substantially hollow cylindrical shape, forcing the entered outside air towhirl inside the first cyclone body; an air communicating member being disposed inside thefirst cyclone body, discharging air having contaminants removed; and an air suction pipebeing disposed at a bottom surface of the first cyclone body, forcing the entered outside air toform the first upwardly whirling air current.According to an embodiment of the present invention, the air communicating member isformed in a substantially hollow cylindrical shape, the air communicating member having anopened top end and a bottom end that is in fluid communication with a plurality of airpassages corresponding to the plurality of second cyclones. According to an embodiment of the present invention, the multi-cyclone dust collectorfurther includes a guiding cone being disposed at a center of the bottom end of the aircommunicating member.According to an embodiment of the present invention, the multi-cyclone dust collectorfurther includes: a second dust collecting chamber being formed to wrap around all theplurality of second cyclones, and collecting the contaminants discharged from the plurality of 第 7 頁 共 12 頁 second cyclones. At this time, the plurality of second cyclones is in contact with the firstcyclone body.According to an embodiment of the present invention, the second dust collecting chamberis formed as a space between the first cyclone body and an inner wall that wraps around all theplurality of second cyclones outside. The first dust collecting chamber is formed as a spacebetween an outer wall wrapping entirely around the inner wall and the first cyclone body, theinner wall, and a part of the first cyclone body that is not wrapped around by the inner wall.According to an embodiment of the present invention, the multi-cyclone dust collectorfurther includes: each of a plurality of second dust collecting chambers being formed to wrap around at least one of the plurality of second cyclones. Gaps, through which contaminantsdischarged from the first cyclone can pass, are formed between the plurality of second dustcollecting chambers.According to an embodiment of the present invention, the plurality of second cyclones isspaced apart from the first cyclone body. The second dust collecting chamber is formed as aspace between the plurality of second cyclones and a dust wall that wraps around all theplurality of second cyclones. The dust wall is in contact with each of the plurality of secondcyclones.According to an embodiment of the present invention, the multi-cyclone dust collector further includes: an upper cover detachably covering the top ends of the first cyclone, the firstdust collecting chamber, and the second dust collecting chamber. The upper cover includes abackflow preventing dam being disposed on a bottom surface of the upper cover forpreventing contaminants collected in the first dust collecting chamber from flowing back intothe first cyclone body.According to still another aspect of the present invention, the multi-cyclone dust collectorfor a vacuum cleaner, includes: a first cyclone forcing outside air, which is entered into a 第 8 頁 共 12 頁 lower portion of the first cyclone, to form a first upwardly whirling air current so as tocentrifugally separate contaminants from the outside air; a plurality of second cyclones beingdisposed around some of the first cyclone, each of the second cyclones sucking air that isdischarged from the first cyclone into a lower portion of each of the second cyclones, each ofthe second cyclones forcing the air to form a second upwardly whirling air current so as tocentrifugally separate contaminants from the air; and a first dust collecting chamber beingdisposed to wrap around the first cyclone and the plurality of second cyclones, collectingcontaminants discharged from the first cyclone.According to an embodiment of the present invention, the first cyclone includes aplurality of cyclones. According to an embodiment of the present invention, each of the plurality of secondcyclones includes a second cyclone body, and a top end of the second cyclone body is inclinedtoward the first cyclone with respect to a bottom end of the second cyclone body.Furthermore, at least one of the second cyclones is formed such that some circumferentialsurface thereof is projected into the first dust collecting chamber.According to yet another aspect of the present invention, a multi-cyclone dust collectorfor a vacuum cleaner includes: at least one first cyclone sucking outside air so as tocentrifugally separate contaminants from the outside air; at least one second cyclone beingdisposed around the at least one first cyclone, the at least one second cyclone sucking air that is discharged from the at least one first cyclone so as to centrifugally separate contaminantsfrom the air; a second dust collecting chamber wrapping around the at least one secondcyclone, so as to collect contaminants discharged from the at least one second cyclone in adirection opposite to the gravity direction; and a first dust collecting chamber wrapping aroundthe at least one first cyclone and the second dust collecting chamber, so as to collectcontaminants discharged from the at least one first cyclone. 第 9 頁 共 12 頁 According to an embodiment of the present invention, the at least one first cyclone forcesthe outside air that is sucked into a bottom surface thereof to whirl upwardly, the at least onefirst cyclone discharges contaminants separated from the outside air into the first dustcollecting chamber through an opened top end of the at least one first cyclone, and the at leastone first cyclone discharges air that has contaminants removed in the gravity direction.According to an embodiment of the present invention, the at least one second cycloneforces air that is discharged from the at least one first cyclone and sucked into a lower portionof the at least one second cyclone to whirl upwardly, the at least one second cyclonedischarges contaminants separated from the air into the second dust collecting chamberthrough an opened top end of the at least one second cyclone, and the at least one second cyclone discharges air that has contaminants removed in the gravity direction.According to another aspect of the present invention, a multi-cyclone dust collector for avacuum cleaner includes: at least one first cyclone sucking outside air so as to separatecontaminants, a first dust collecting chamber collecting contaminants separated by the at leastone first cyclone, at least one second cyclone centrifugally re-separating air discharged fromthe at least one first cyclone, and a second dust collecting chamber collecting contaminantsseparated by the at least one second cyclone, wherein the second dust collecting chamberwraps around some of a circumferential surface of the at least one first cyclone, and the firstdust collecting chamber wraps around a circumferential surface of the second dust collectingchamber and some of the circumferential surface of the at least one first cyclone. According to an embodiment of the present invention, the at least one first cyclone is on acenter of the multi-cyclone dust collector. And, the at least one first and second cyclonesdischarge separated contaminants in a direction opposite to the gravity direction. Also, the atleast one first and second cyclones suck air into a lower portion thereof and then discharge airthrough the lower portion thereof. 第 10 頁 共 12 頁 According to another aspect of the present invention, a method of collectingcontaminants for a multi-cyclone dust collector, includes: sucking outside air into a lowerportion of a first cyclone so as to form the outside air into a first upwardly whirling air currentinside the first cyclone; separating contaminants from the outside air by centrifugal force so asto discharge the contaminants in a direction opposite to the gravity direction from the firstcyclone; discharging air that has contaminants removed in the gravity direction from the firstcyclone; sucking the air discharged from the first cyclone into a lower portion of a secondcyclone so as to form the air into a second upwardly whirling air current inside the secondcyclone; separating fine contaminants from the air by centrifugal force so as to discharge thefine contaminants in a direction opposite to the gravity direction from the second cyclone; and discharging air that has fine contaminants removed in the gravity direction from the secondcyclone.With the multi-cyclone dust collector for the vacuum cleaner according to embodimentsof the present invention, entering air and discharging air do not collide with each other in thefirst and second cyclones so that a dust collecting efficiency of the multi-cyclone dustcollector is increased.Furthermore, with the multi-cyclone dust collector according to embodiments of thepresent invention, as sucked dust-laden air passes through the first cyclone, relatively largecontaminants are separated, and then, as the air discharged from the first cyclone passes through the second cyclone, fine contaminants that remain in the air are separated. So themulti-cyclone dust collector according to the present invention has a high dust collectingefficiency for fine contaminants.Furthermore, with the multi-cyclone dust collector according to embodiments of thepresent invention, the first and second cyclones, where upwardly whirling air currents areformed, are isolated from the first and second dust collecting chamber where contaminants are 第 11 頁 共 12 頁 collected so that the multi-cyclone dust collector has a high dust collecting efficiency and aprolonged filter maintenance cycle.T
收藏