電風扇(shan)工(gong)作原(yuan)理及檢修
風扇的分類:
散熱風扇通常分為以下三(san)類:
軸(zhou)流(liu)式:氣(qi)流(liu)出口方向(xiang)與軸(zhou)心方向(xiang)相同(tong)。
離心式:利用(yong)離心力作用(yong)將氣流沿(yan)著葉片向外甩(shuai)出。
混流式:擁有(you)以上兩種氣(qi)流方式。
電風扇電路圖
以上(shang)是比較常見的(de)(de)家用電風扇(shan)的(de)(de)電路圖(tu),從中(zhong)我們也不難(nan)看出它的(de)(de)一些原(yuan)理,但(dan)(dan)是現在電風扇(shan)產品越來越多,其(qi)電路圖(tu)也越來越復雜,但(dan)(dan)是還是萬變不離其(qi)中(zhong)。
電風扇工作原理
電(dian)(dian)風扇(shan)中(zhong)的(de)電(dian)(dian)流是交流電(dian)(dian),主要的(de)工作原理就(jiu)是通電(dian)(dian)線圈在磁(ci)場中(zhong)受(shou)力(li)而轉動(dong)。電(dian)(dian)能(neng)轉化(hua)為機(ji)械能(neng),轉動(dong)風葉,同時由(you)于線圈電(dian)(dian)阻,會產生一些熱能(neng),所以一般電(dian)(dian)風扇(shan)使用過久表面會熱。電(dian)(dian)風扇(shan)的(de)原理比較簡(jian)單(dan),一般在初中(zhong)的(de)物(wu)理課(ke)程上(shang)都會學到(dao)。
電風扇轉不動的原因
首先還是要確定一下是不是一些外部原因。諸如插頭沒有插好,風扇開關沒有全部開啟,一般的風扇還應該注意是否定時的關掉了,如果這些都沒有問題的話,就可能是電風扇扇本身的原因。
電(dian)風(feng)扇(shan)(shan)本身(shen)的原因可能(neng)包括了(le)風(feng)葉(xie)可能(neng)太(tai)久了(le),電(dian)機(ji)的內(nei)阻變(bian)大(da),導致風(feng)葉(xie)無法(fa)正常轉(zhuan)動(dong)(dong);風(feng)扇(shan)(shan)過熱引起了(le)電(dian)機(ji)帶負載能(neng)力(li)變(bian)差(cha),導致無法(fa)轉(zhuan)動(dong)(dong);電(dian)機(ji)內(nei)部的保護裝置(zhi)過熱短路;電(dian)風(feng)扇(shan)(shan)的啟動(dong)(dong)電(dian)容容量變(bian)小;電(dian)風(feng)扇(shan)(shan)轉(zhuan)軸軸向間隙過大(da)也會引發電(dian)風(feng)扇(shan)(shan)問題。
電風扇轉不動的修理方法
先檢(jian)查一(yi)下(xia)電(dian)風(feng)扇(shan)以外的(de)(de)問(wen)(wen)題(ti)(ti)(ti)是(shi)不(bu)(bu)(bu)是(shi)全(quan)部都弄妥當(dang)了;然后如果(guo)是(shi)風(feng)葉不(bu)(bu)(bu)轉的(de)(de)話就關閉電(dian)源,在風(feng)葉轉動的(de)(de)軸上面(mian)加一(yi)些潤滑油(you);其(qi)他的(de)(de)問(wen)(wen)題(ti)(ti)(ti)可能就會涉及到更(geng)(geng)換(huan)(huan)軸套、拆換(huan)(huan)電(dian)容、調(diao)整墊片、電(dian)線損壞更(geng)(geng)換(huan)(huan)電(dian)線等(deng)問(wen)(wen)題(ti)(ti)(ti),一(yi)般不(bu)(bu)(bu)是(shi)專業的(de)(de)人員(yuan)就要請維修師傅來看一(yi)下(xia)了,不(bu)(bu)(bu)過一(yi)般也(ye)不(bu)(bu)(bu)是(shi)好大(da)的(de)(de)問(wen)(wen)題(ti)(ti)(ti),也(ye)花不(bu)(bu)(bu)了多少錢。
散熱風扇的原理及性能
原理:風(feng)扇的(de)工作原(yuan)理是按(an)能(neng)(neng)量轉化來(lai)實現(xian)的(de),即:電(dian)(dian)能(neng)(neng)→電(dian)(dian)磁(ci)能(neng)(neng)→機械(xie)能(neng)(neng)→動能(neng)(neng)。其電(dian)(dian)路(lu)原(yuan)理一般分為多種形(xing)式,采用的(de)電(dian)(dian)路(lu)不(bu)同(tong),風(feng)扇的(de)性能(neng)(neng)就會有差異。
轉 速:轉(zhuan)速(su)(su)指風扇旋(xuan)轉(zhuan)的速(su)(su)度(du),通常以1分鐘內轉(zhuan)動的圈數來衡量,即:rpm。轉(zhuan)速(su)(su)與(yu)(yu)機(ji)電繞(rao)線匝數、線徑(jing)、扇葉葉輪外徑(jing)與(yu)(yu)底(di)徑(jing),葉片形(xing)狀(zhuang)及所用軸承等(deng)因素有關,轉(zhuan)速(su)(su)增大(da),風量相應增大(da)。
轉速(su)(su)值的大(da)小,在一(yi)定程度(du)上(shang)代(dai)表(biao)了風(feng)量的大(da)小,在條件一(yi)定時,轉速(su)(su)越大(da),則噪音及(ji)振動會相(xiang)應加大(da),因此,在風(feng)量滿足散熱要求的情況下,應盡量使用低轉速(su)(su)風(feng)扇(shan)(shan)。一(yi)般轉速(su)(su)大(da)小(以DC軸(zhou)流風(feng)扇(shan)(shan)為例):2510風(feng)扇(shan)(shan)7000~12000rpm;3010風(feng)扇(shan)(shan)5000~9000rpm;4010風(feng)扇(shan)(shan)5000~7000rpm;5010風(feng)扇(shan)(shan)3500~5000rpm;6025風(feng)扇(shan)(shan)2600~4500rpm;7025風(feng)扇(shan)(shan)2400~3600rpm;8025風(feng)扇(shan)(shan)2000~3500rpm;9225風(feng)扇(shan)(shan)1600~3100rpm;12025風(feng)扇(shan)(shan)1500~2500rpm;12038風(feng)扇(shan)(shan)2000~3200rpm。
風(feng)扇轉速(su)可(ke)在啟動(dong)電腦時通過(guo)BIOS測(ce)試(shi)(shi)(shi),或通過(guo)其他(ta)主板自(zi)帶的(de)監控軟件測(ce)試(shi)(shi)(shi);也可(ke)以通過(guo)轉速(su)測(ce)試(shi)(shi)(shi)儀測(ce)試(shi)(shi)(shi)。注意(yi):前(qian)兩種方(fang)式必須是支持測(ce)速(su)功能(neng)的(de)風(feng)扇才(cai)能(neng)測(ce)出。
風量與風壓:風(feng)量與風(feng)壓(ya)的測(ce)試(shi)方法有(you)兩種,一(yi)(yi)(yi)是(shi)用(yong)(yong)風(feng)洞儀測(ce)試(shi),另一(yi)(yi)(yi)種是(shi)用(yong)(yong)雙(shuang)箱法測(ce)。但對于一(yi)(yi)(yi)般用(yong)(yong)戶而言,沒(mei)有(you)這樣的設備。只能根(gen)據(ju)廠家提供(gong)的數(shu)據(ju)作(zuo)為(wei)參(can)考,最(zui)終要看降溫效果。
風量(liang):風量(liang)是(shi)指風扇通(tong)(tong)風面(mian)(mian)積(ji)平(ping)面(mian)(mian)速(su)(su)度之(zhi)積(ji)。通(tong)(tong)風面(mian)(mian)積(ji)是(shi)出口面(mian)(mian)積(ji)減(jian)去渦舌處(chu)的投(tou)影面(mian)(mian)積(ji)。平(ping)面(mian)(mian)速(su)(su)度是(shi)氣流通(tong)(tong)過整個平(ping)面(mian)(mian)的氣體運動速(su)(su)度,單位是(shi)m3/s 。平(ping)面(mian)(mian)速(su)(su)度一定(ding)(ding)時,扇葉葉輪(lun)外徑越大(da)(da),通(tong)(tong)風面(mian)(mian)積(ji)越大(da)(da),風量(liang)則越大(da)(da)。平(ping)面(mian)(mian)速(su)(su)度由轉(zhuan)子的轉(zhuan)速(su)(su)和風壓決定(ding)(ding)。通(tong)(tong)風面(mian)(mian)積(ji)一定(ding)(ding)時,平(ping)面(mian)(mian)速(su)(su)度越大(da)(da),風量(liang)越大(da)(da)。風量(liang)越大(da)(da),空(kong)氣吸熱(re)(re)量(liang)則越大(da)(da),空(kong)氣流動轉(zhuan)移時能夠(gou)帶周能帶走更多的熱(re)(re)量(liang),扇熱(re)(re)效果(guo)越明(ming)顯。
風壓(ya)(ya)(ya):為(wei)進行正常通(tong)風,需要(yao)克(ke)服風扇(shan)通(tong)風行程內的(de)阻力(li)(li),風扇(shan)必(bi)須(xu)產生克(ke)服送(song)風阻力(li)(li)的(de)壓(ya)(ya)(ya)力(li)(li),測(ce)量到的(de)壓(ya)(ya)(ya)力(li)(li)的(de)變化值稱為(wei)靜壓(ya)(ya)(ya),即(ji)最大(da)靜壓(ya)(ya)(ya)與大(da)氣(qi)壓(ya)(ya)(ya)的(de)差(cha)壓(ya)(ya)(ya)。它是氣(qi)體對平行于(yu)物體表(biao)面(mian)作(zuo)用的(de)壓(ya)(ya)(ya)力(li)(li),靜壓(ya)(ya)(ya)是通(tong)過垂(chui)直于(yu)其(qi)表(biao)面(mian)的(de)孔測(ce)量出來的(de)。把氣(qi)體流動中所需要(yao)動能轉化為(wei)壓(ya)(ya)(ya)力(li)(li)形式稱為(wei)動壓(ya)(ya)(ya)。
為實(shi)現(xian)送風(feng)(feng)(feng)(feng)的(de)(de)(de)(de)(de)目的(de)(de)(de)(de)(de),需要(yao)有(you)靜壓(ya)(ya)和動壓(ya)(ya)。全(quan)壓(ya)(ya)為靜壓(ya)(ya)與動壓(ya)(ya)的(de)(de)(de)(de)(de)代數(shu)和,全(quan)壓(ya)(ya)是(shi)指由風(feng)(feng)(feng)(feng)扇(shan)(shan)(shan)所給(gei)定的(de)(de)(de)(de)(de)的(de)(de)(de)(de)(de)全(quan)壓(ya)(ya)增(zeng)加量(liang),即風(feng)(feng)(feng)(feng)扇(shan)(shan)(shan)的(de)(de)(de)(de)(de)出(chu)口和進口之(zhi)間的(de)(de)(de)(de)(de)全(quan)壓(ya)(ya)之(zhi)差。在實(shi)際應用(yong)中,標稱(cheng)的(de)(de)(de)(de)(de)最(zui)(zui)大(da)風(feng)(feng)(feng)(feng)量(liang)值并不(bu)是(shi)實(shi)際扇(shan)(shan)(shan)熱片(pian)得到的(de)(de)(de)(de)(de)送風(feng)(feng)(feng)(feng)量(liang),風(feng)(feng)(feng)(feng)量(liang)大(da),并不(bu)代表通(tong)風(feng)(feng)(feng)(feng)能(neng)力強。因空(kong)氣流(liu)動時,氣流(liu)在其流(liu)動路徑會(hui)遇上扇(shan)(shan)(shan)熱稽片(pian)或元件的(de)(de)(de)(de)(de)阻擾(rao),其阻抗(kang)會(hui)限制空(kong)氣自由流(liu)通(tong)。即風(feng)(feng)(feng)(feng)量(liang)增(zeng)大(da)時,風(feng)(feng)(feng)(feng)壓(ya)(ya)會(hui)減小。因此(ci)必(bi)須有(you)一個最(zui)(zui)佳操(cao)作(zuo)工作(zuo)點,即風(feng)(feng)(feng)(feng)扇(shan)(shan)(shan)性能(neng)曲線(xian)與風(feng)(feng)(feng)(feng)阻曲線(xian)的(de)(de)(de)(de)(de)交點。在工作(zuo)點,風(feng)(feng)(feng)(feng)扇(shan)(shan)(shan)特(te)(te)性曲線(xian)之(zhi)斜率(lv)(lv)為最(zui)(zui)小,而(er)系統特(te)(te)性曲線(xian)之(zhi)變化(hua)率(lv)(lv)為最(zui)(zui)低。注意此(ci)時的(de)(de)(de)(de)(de)風(feng)(feng)(feng)(feng)扇(shan)(shan)(shan)靜態效(xiao)率(lv)(lv)(風(feng)(feng)(feng)(feng)量(liang)×風(feng)(feng)(feng)(feng)壓(ya)(ya)÷耗電)為最(zui)(zui)佳。 當然有(you)時為了(le)能(neng)減少(shao)系統阻抗(kang),甚至(zhi)選用(yong)尺寸較小的(de)(de)(de)(de)(de)風(feng)(feng)(feng)(feng)扇(shan)(shan)(shan),也可(ke)以獲得相同的(de)(de)(de)(de)(de)風(feng)(feng)(feng)(feng)量(liang)。
風扇的軸承系統:
風扇的(de)(de)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)系(xi)(xi)(xi)統一般(ban)(ban)建議最(zui)好選用(yong)滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)珠軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng),因為(wei)(wei)扇(shan)熱風(feng)(feng)(feng)扇(shan)的(de)(de)壽(shou)(shou)命(ming)通常取決于(yu)其(qi)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)的(de)(de)可(ke)靠(kao)性,滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)珠軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)系(xi)(xi)(xi)統已被證實具有高效率與(yu)低生熱的(de)(de)特點。滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)珠軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)屬(shu)滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)動摩(mo)(mo)擦,由金屬(shu)珠滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)動,接觸(chu)面小(xiao),摩(mo)(mo)擦系(xi)(xi)(xi)數(shu)(shu)小(xiao);而(er)(er)含(han)油(you)(you)(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)為(wei)(wei)滑(hua)(hua)(hua)動摩(mo)(mo)擦,接觸(chu)面大(da),長期使(shi)用(yong)后,油(you)(you)(you)(you)會(hui)揮發,軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)容易磨損,摩(mo)(mo)擦系(xi)(xi)(xi)數(shu)(shu)大(da),后期噪音較大(da),壽(shou)(shou)命(ming)短。品(pin)質好的(de)(de)風(feng)(feng)(feng)扇(shan)除(chu)了通風(feng)(feng)(feng)量大(da)、風(feng)(feng)(feng)壓高以(yi)外,可(ke)靠(kao)性也是非常重(zhong)要的(de)(de),風(feng)(feng)(feng)扇(shan)使(shi)用(yong)的(de)(de)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)形式在此顯得非常重(zhong)要。高速(su)風(feng)(feng)(feng)扇(shan)一律使(shi)用(yong)滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)珠軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)(Ball bearing)而(er)(er)低速(su)風(feng)(feng)(feng)扇(shan)則(ze)使(shi)用(yong)成(cheng)(cheng)本低廉的(de)(de)含(han)油(you)(you)(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)(Sleeve bearing)。含(han)油(you)(you)(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)風(feng)(feng)(feng)扇(shan)只(zhi)用(yong)一個軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng);而(er)(er)滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)珠軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)風(feng)(feng)(feng)扇(shan)都需要兩(liang)個軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng),單滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)珠軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng),是“1 Ball + 1 Sleeve”,依然帶有含(han)油(you)(you)(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)的(de)(de)成(cheng)(cheng)分。比單滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)珠更高級的(de)(de)是雙滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)珠軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng),即Two Balls。含(han)油(you)(you)(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)壽(shou)(shou)命(ming)一般(ban)(ban)為(wei)(wei)10000小(xiao)時(shi),單滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)珠軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)為(wei)(wei)30000小(xiao)時(shi),雙滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)珠軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)為(wei)(wei)50000小(xiao)時(shi)以(yi)上(環(huan)境溫度均設定在25℃以(yi)下時(shi))。風(feng)(feng)(feng)扇(shan)使(shi)用(yong)的(de)(de)含(han)油(you)(you)(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)由銅基粉末燒結(jie)而(er)(er)成(cheng)(cheng),使(shi)用(yong)含(han)油(you)(you)(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)需加(jia)潤(run)滑(hua)(hua)(hua)油(you)(you)(you)(you)以(yi)減少滑(hua)(hua)(hua)動摩(mo)(mo)數(shu)(shu),潤(run)滑(hua)(hua)(hua)油(you)(you)(you)(you)由鋰基潤(run)滑(hua)(hua)(hua)脂加(jia)特制機(ji)油(you)(you)(you)(you)調制而(er)(er)成(cheng)(cheng)。隨著長時(shi)間的(de)(de)運轉,軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)內的(de)(de)機(ji)油(you)(you)(you)(you)會(hui)揮發而(er)(er)變(bian)干(gan),摩(mo)(mo)擦系(xi)(xi)(xi)數(shu)(shu)增大(da),風(feng)(feng)(feng)扇(shan)運轉受影(ying)響,可(ke)能出現(xian)異音,轉速(su)偏慢(man)甚(shen)至(zhi)不(bu)轉現(xian)象。而(er)(er)滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)珠軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)(cheng)由滾(gun)(gun)(gun)(gun)(gun)(gun)(gun)動摩(mo)(mo)擦取代了滑(hua)(hua)(hua)動摩(mo)(mo)擦,摩(mo)(mo)擦系(xi)(xi)(xi)數(shu)(shu)小(xiao)并克服了摩(mo)(mo)擦系(xi)(xi)(xi)數(shu)(shu)容易變(bian)的(de)(de)缺點,因而(er)(er)運轉穩定性強,壽(shou)(shou)命(ming)相對要長得多。