電(dian)風扇工作原理及檢修
風扇的分類:
散熱風扇通常分為(wei)以下三類:
軸(zhou)流式:氣流出口(kou)方向與(yu)軸(zhou)心方向相同。
離心式:利用(yong)離心力作用(yong)將(jiang)氣流沿著葉片(pian)向外甩(shuai)出。
混流式(shi):擁(yong)有(you)以上兩種氣流方式(shi)。
電風扇電路圖
以上是比較常見的(de)家(jia)用電風(feng)扇的(de)電路(lu)圖,從中(zhong)(zhong)我們也不難看出(chu)它(ta)的(de)一(yi)些原理,但是現在(zai)電風(feng)扇產品越(yue)來越(yue)多,其電路(lu)圖也越(yue)來越(yue)復雜,但是還是萬變不離(li)其中(zhong)(zhong)。
電風扇工作原理
電(dian)(dian)(dian)(dian)風(feng)扇(shan)中的(de)(de)電(dian)(dian)(dian)(dian)流是交流電(dian)(dian)(dian)(dian),主(zhu)要的(de)(de)工(gong)作原理就是通(tong)電(dian)(dian)(dian)(dian)線圈在(zai)磁場中受力而轉(zhuan)(zhuan)動。電(dian)(dian)(dian)(dian)能(neng)轉(zhuan)(zhuan)化為機械能(neng),轉(zhuan)(zhuan)動風(feng)葉,同時由于(yu)線圈電(dian)(dian)(dian)(dian)阻,會(hui)產生一些熱能(neng),所(suo)以一般(ban)電(dian)(dian)(dian)(dian)風(feng)扇(shan)使用過久(jiu)表(biao)面(mian)會(hui)熱。電(dian)(dian)(dian)(dian)風(feng)扇(shan)的(de)(de)原理比較簡單,一般(ban)在(zai)初(chu)中的(de)(de)物理課程上都會(hui)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)(dian)風扇(shan)本(ben)身的(de)原(yuan)因可能包括了風葉可能太久了,電(dian)(dian)機(ji)的(de)內阻變大(da),導(dao)致風葉無法正(zheng)常轉動;風扇(shan)過(guo)熱引起了電(dian)(dian)機(ji)帶負載能力(li)變差(cha),導(dao)致無法轉動;電(dian)(dian)機(ji)內部的(de)保護裝置過(guo)熱短路(lu);電(dian)(dian)風扇(shan)的(de)啟動電(dian)(dian)容(rong)容(rong)量變小;電(dian)(dian)風扇(shan)轉軸(zhou)軸(zhou)向間隙(xi)過(guo)大(da)也會引發電(dian)(dian)風扇(shan)問題。
電風扇轉不動的修理方法
先(xian)檢(jian)查(cha)一(yi)(yi)下電風扇以外的(de)問題(ti)是(shi)不(bu)(bu)是(shi)全部(bu)都弄(nong)妥當了;然后如果是(shi)風葉不(bu)(bu)轉(zhuan)的(de)話就(jiu)關閉電源,在風葉轉(zhuan)動的(de)軸上面加(jia)一(yi)(yi)些(xie)潤滑油;其他的(de)問題(ti)可能就(jiu)會涉及到更換軸套(tao)、拆換電容、調(diao)整墊片(pian)、電線損壞更換電線等問題(ti),一(yi)(yi)般(ban)不(bu)(bu)是(shi)專業的(de)人員就(jiu)要(yao)請維修師(shi)傅來看一(yi)(yi)下了,不(bu)(bu)過一(yi)(yi)般(ban)也(ye)(ye)不(bu)(bu)是(shi)好大的(de)問題(ti),也(ye)(ye)花不(bu)(bu)了多(duo)少錢。
散熱風扇的原理及性能
原理:風扇的工作原(yuan)(yuan)理是按能量轉化(hua)來實現的,即(ji):電(dian)能→電(dian)磁(ci)能→機械(xie)能→動能。其電(dian)路(lu)原(yuan)(yuan)理一般分為多種形式,采用的電(dian)路(lu)不同,風扇的性(xing)能就(jiu)會有(you)差異。
轉 速:轉(zhuan)速(su)(su)指風(feng)扇旋轉(zhuan)的(de)速(su)(su)度,通常以1分鐘內轉(zhuan)動的(de)圈數來衡量,即:rpm。轉(zhuan)速(su)(su)與機電(dian)繞線匝(za)數、線徑、扇葉(xie)葉(xie)輪外(wai)徑與底徑,葉(xie)片形狀及(ji)所(suo)用軸承(cheng)等因素有關,轉(zhuan)速(su)(su)增大,風(feng)量相應增大。
轉速值的大小,在(zai)(zai)一定程度(du)上代(dai)表了風(feng)(feng)(feng)量(liang)的大小,在(zai)(zai)條件一定時,轉速越大,則噪(zao)音及振動會相(xiang)應加大,因此,在(zai)(zai)風(feng)(feng)(feng)量(liang)滿(man)足(zu)散(san)熱(re)要求(qiu)的情況下,應盡量(liang)使用(yong)低轉速風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)。一般轉速大小(以DC軸流風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)為例):2510風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)7000~12000rpm;3010風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)5000~9000rpm;4010風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)5000~7000rpm;5010風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)3500~5000rpm;6025風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)2600~4500rpm;7025風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)2400~3600rpm;8025風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)2000~3500rpm;9225風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)1600~3100rpm;12025風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)1500~2500rpm;12038風(feng)(feng)(feng)扇(shan)(shan)(shan)(shan)(shan)(shan)2000~3200rpm。
風扇轉速(su)可在啟動電腦時通過(guo)(guo)BIOS測(ce)(ce)試,或通過(guo)(guo)其他主板自(zi)帶的(de)監控軟件(jian)測(ce)(ce)試;也可以通過(guo)(guo)轉速(su)測(ce)(ce)試儀測(ce)(ce)試。注(zhu)意:前兩種方式必須是支持測(ce)(ce)速(su)功能(neng)的(de)風扇才(cai)能(neng)測(ce)(ce)出。
風量與風壓:風量與(yu)風壓的測試方法有兩種,一(yi)是(shi)用風洞儀測試,另一(yi)種是(shi)用雙箱法測。但對于一(yi)般用戶而言,沒有這樣的設備。只能(neng)根據(ju)廠家提供(gong)的數據(ju)作為參考(kao),最(zui)終要看降溫效果。
風(feng)(feng)(feng)量(liang)(liang):風(feng)(feng)(feng)量(liang)(liang)是(shi)指風(feng)(feng)(feng)扇(shan)通(tong)(tong)風(feng)(feng)(feng)面(mian)積(ji)平(ping)面(mian)速(su)(su)(su)度(du)之積(ji)。通(tong)(tong)風(feng)(feng)(feng)面(mian)積(ji)是(shi)出(chu)口(kou)面(mian)積(ji)減(jian)去渦舌(she)處的投影面(mian)積(ji)。平(ping)面(mian)速(su)(su)(su)度(du)是(shi)氣流通(tong)(tong)過整個(ge)平(ping)面(mian)的氣體運動速(su)(su)(su)度(du),單位是(shi)m3/s 。平(ping)面(mian)速(su)(su)(su)度(du)一定(ding)時(shi),扇(shan)葉葉輪外徑越(yue)大(da),通(tong)(tong)風(feng)(feng)(feng)面(mian)積(ji)越(yue)大(da),風(feng)(feng)(feng)量(liang)(liang)則(ze)越(yue)大(da)。平(ping)面(mian)速(su)(su)(su)度(du)由(you)轉子的轉速(su)(su)(su)和風(feng)(feng)(feng)壓決(jue)定(ding)。通(tong)(tong)風(feng)(feng)(feng)面(mian)積(ji)一定(ding)時(shi),平(ping)面(mian)速(su)(su)(su)度(du)越(yue)大(da),風(feng)(feng)(feng)量(liang)(liang)越(yue)大(da)。風(feng)(feng)(feng)量(liang)(liang)越(yue)大(da),空(kong)氣吸(xi)熱量(liang)(liang)則(ze)越(yue)大(da),空(kong)氣流動轉移(yi)時(shi)能夠帶(dai)周能帶(dai)走(zou)更(geng)多(duo)的熱量(liang)(liang),扇(shan)熱效果越(yue)明(ming)顯。
風(feng)(feng)壓(ya):為進行正(zheng)常通(tong)風(feng)(feng),需(xu)要(yao)克(ke)(ke)服風(feng)(feng)扇通(tong)風(feng)(feng)行程內的(de)阻(zu)力(li)(li),風(feng)(feng)扇必須產(chan)生克(ke)(ke)服送風(feng)(feng)阻(zu)力(li)(li)的(de)壓(ya)力(li)(li),測量到的(de)壓(ya)力(li)(li)的(de)變化值稱為靜(jing)壓(ya),即最大靜(jing)壓(ya)與大氣(qi)壓(ya)的(de)差(cha)壓(ya)。它是(shi)氣(qi)體對平行于物體表面作用的(de)壓(ya)力(li)(li),靜(jing)壓(ya)是(shi)通(tong)過(guo)垂直(zhi)于其表面的(de)孔測量出來的(de)。把氣(qi)體流動(dong)(dong)中所需(xu)要(yao)動(dong)(dong)能轉化為壓(ya)力(li)(li)形式稱為動(dong)(dong)壓(ya)。
為(wei)實現送(song)風(feng)(feng)(feng)的(de)(de)目(mu)的(de)(de),需要(yao)有(you)靜(jing)(jing)壓(ya)(ya)(ya)(ya)(ya)和(he)動壓(ya)(ya)(ya)(ya)(ya)。全(quan)壓(ya)(ya)(ya)(ya)(ya)為(wei)靜(jing)(jing)壓(ya)(ya)(ya)(ya)(ya)與動壓(ya)(ya)(ya)(ya)(ya)的(de)(de)代數和(he),全(quan)壓(ya)(ya)(ya)(ya)(ya)是(shi)指由風(feng)(feng)(feng)扇所(suo)給定(ding)的(de)(de)的(de)(de)全(quan)壓(ya)(ya)(ya)(ya)(ya)增加量(liang)(liang),即(ji)風(feng)(feng)(feng)扇的(de)(de)出口和(he)進口之間的(de)(de)全(quan)壓(ya)(ya)(ya)(ya)(ya)之差。在實際(ji)應(ying)用中,標稱的(de)(de)最(zui)大風(feng)(feng)(feng)量(liang)(liang)值并(bing)(bing)不是(shi)實際(ji)扇熱(re)片得到的(de)(de)送(song)風(feng)(feng)(feng)量(liang)(liang),風(feng)(feng)(feng)量(liang)(liang)大,并(bing)(bing)不代表通風(feng)(feng)(feng)能(neng)力強。因(yin)(yin)空(kong)氣流(liu)(liu)動時(shi),氣流(liu)(liu)在其流(liu)(liu)動路徑(jing)會遇上扇熱(re)稽(ji)片或元件的(de)(de)阻擾,其阻抗會限制空(kong)氣自由流(liu)(liu)通。即(ji)風(feng)(feng)(feng)量(liang)(liang)增大時(shi),風(feng)(feng)(feng)壓(ya)(ya)(ya)(ya)(ya)會減小。因(yin)(yin)此必須(xu)有(you)一(yi)個(ge)最(zui)佳操作(zuo)工作(zuo)點(dian),即(ji)風(feng)(feng)(feng)扇性(xing)能(neng)曲(qu)線與風(feng)(feng)(feng)阻曲(qu)線的(de)(de)交點(dian)。在工作(zuo)點(dian),風(feng)(feng)(feng)扇特性(xing)曲(qu)線之斜率為(wei)最(zui)小,而系統(tong)特性(xing)曲(qu)線之變化(hua)率為(wei)最(zui)低。注意此時(shi)的(de)(de)風(feng)(feng)(feng)扇靜(jing)(jing)態效率(風(feng)(feng)(feng)量(liang)(liang)×風(feng)(feng)(feng)壓(ya)(ya)(ya)(ya)(ya)÷耗電)為(wei)最(zui)佳。 當然有(you)時(shi)為(wei)了能(neng)減少系統(tong)阻抗,甚(shen)至選用尺寸較小的(de)(de)風(feng)(feng)(feng)扇,也可以(yi)獲(huo)得相同的(de)(de)風(feng)(feng)(feng)量(liang)(liang)。
風扇的軸承系統:
風扇的(de)(de)(de)(de)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)系(xi)(xi)(xi)(xi)統一(yi)般建議(yi)最(zui)好(hao)選用滾(gun)(gun)珠(zhu)(zhu)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng),因(yin)為扇(shan)(shan)熱風(feng)(feng)(feng)扇(shan)(shan)的(de)(de)(de)(de)壽命通常取決(jue)于其軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)的(de)(de)(de)(de)可靠(kao)性(xing),滾(gun)(gun)珠(zhu)(zhu)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)系(xi)(xi)(xi)(xi)統已被證(zheng)實具(ju)有(you)高效率與低生熱的(de)(de)(de)(de)特(te)點(dian)。滾(gun)(gun)珠(zhu)(zhu)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)屬滾(gun)(gun)動(dong)摩擦(ca)(ca),由(you)金屬珠(zhu)(zhu)滾(gun)(gun)動(dong),接(jie)觸(chu)面小(xiao),摩擦(ca)(ca)系(xi)(xi)(xi)(xi)數(shu)小(xiao);而(er)(er)含(han)(han)油(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)為滑(hua)(hua)(hua)(hua)動(dong)摩擦(ca)(ca),接(jie)觸(chu)面大,長(chang)期使(shi)用后(hou),油(you)(you)會(hui)揮發(fa),軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)容易磨損,摩擦(ca)(ca)系(xi)(xi)(xi)(xi)數(shu)大,后(hou)期噪(zao)音較大,壽命短。品質好(hao)的(de)(de)(de)(de)風(feng)(feng)(feng)扇(shan)(shan)除了通風(feng)(feng)(feng)量大、風(feng)(feng)(feng)壓高以外,可靠(kao)性(xing)也是非(fei)常重(zhong)要(yao)(yao)的(de)(de)(de)(de),風(feng)(feng)(feng)扇(shan)(shan)使(shi)用的(de)(de)(de)(de)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)形式在此顯得(de)非(fei)常重(zhong)要(yao)(yao)。高速(su)風(feng)(feng)(feng)扇(shan)(shan)一(yi)律使(shi)用滾(gun)(gun)珠(zhu)(zhu)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(Ball bearing)而(er)(er)低速(su)風(feng)(feng)(feng)扇(shan)(shan)則(ze)使(shi)用成(cheng)本低廉的(de)(de)(de)(de)含(han)(han)油(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)(Sleeve bearing)。含(han)(han)油(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)風(feng)(feng)(feng)扇(shan)(shan)只(zhi)用一(yi)個軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng);而(er)(er)滾(gun)(gun)珠(zhu)(zhu)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)風(feng)(feng)(feng)扇(shan)(shan)都(dou)需要(yao)(yao)兩個軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng),單滾(gun)(gun)珠(zhu)(zhu)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng),是“1 Ball + 1 Sleeve”,依然(ran)帶有(you)含(han)(han)油(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)的(de)(de)(de)(de)成(cheng)分。比單滾(gun)(gun)珠(zhu)(zhu)更高級的(de)(de)(de)(de)是雙滾(gun)(gun)珠(zhu)(zhu)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng),即Two Balls。含(han)(han)油(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)壽命一(yi)般為10000小(xiao)時(shi),單滾(gun)(gun)珠(zhu)(zhu)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)為30000小(xiao)時(shi),雙滾(gun)(gun)珠(zhu)(zhu)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)為50000小(xiao)時(shi)以上(環(huan)境溫度均(jun)設定(ding)(ding)在25℃以下時(shi))。風(feng)(feng)(feng)扇(shan)(shan)使(shi)用的(de)(de)(de)(de)含(han)(han)油(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)由(you)銅基粉(fen)末燒結而(er)(er)成(cheng),使(shi)用含(han)(han)油(you)(you)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)需加(jia)潤滑(hua)(hua)(hua)(hua)油(you)(you)以減少滑(hua)(hua)(hua)(hua)動(dong)摩數(shu),潤滑(hua)(hua)(hua)(hua)油(you)(you)由(you)鋰基潤滑(hua)(hua)(hua)(hua)脂(zhi)加(jia)特(te)制機油(you)(you)調制而(er)(er)成(cheng)。隨著長(chang)時(shi)間的(de)(de)(de)(de)運(yun)轉(zhuan),軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)內的(de)(de)(de)(de)機油(you)(you)會(hui)揮發(fa)而(er)(er)變干,摩擦(ca)(ca)系(xi)(xi)(xi)(xi)數(shu)增大,風(feng)(feng)(feng)扇(shan)(shan)運(yun)轉(zhuan)受(shou)影響,可能出現(xian)異音,轉(zhuan)速(su)偏慢甚(shen)至不(bu)轉(zhuan)現(xian)象。而(er)(er)滾(gun)(gun)珠(zhu)(zhu)軸(zhou)(zhou)(zhou)承(cheng)(cheng)(cheng)由(you)滾(gun)(gun)動(dong)摩擦(ca)(ca)取代(dai)了滑(hua)(hua)(hua)(hua)動(dong)摩擦(ca)(ca),摩擦(ca)(ca)系(xi)(xi)(xi)(xi)數(shu)小(xiao)并克(ke)服了摩擦(ca)(ca)系(xi)(xi)(xi)(xi)數(shu)容易變的(de)(de)(de)(de)缺點(dian),因(yin)而(er)(er)運(yun)轉(zhuan)穩定(ding)(ding)性(xing)強,壽命相對要(yao)(yao)長(chang)得(de)多。