構 造
防爆(bao)交(jiao)(jiao)流(liu)伺(si)服(fu)(fu)電(dian)(dian)機(ji)通常(chang)都是(shi)單相(xiang)(xiang)異步電(dian)(dian)動(dong)機(ji)，有(you)(you)鼠(shu)籠形轉(zhuan)(zhuan)子(zi)(zi)(zi)和(he)(he)杯(bei)形轉(zhuan)(zhuan)子(zi)(zi)(zi)兩(liang)種(zhong)結(jie)(jie)構形式。與普通電(dian)(dian)機(ji)一樣，交(jiao)(jiao)流(liu)伺(si)服(fu)(fu)電(dian)(dian)機(ji)也由(you)定子(zi)(zi)(zi)和(he)(he)轉(zhuan)(zhuan)子(zi)(zi)(zi)構成。定子(zi)(zi)(zi)上(shang)有(you)(you)兩(liang)個繞組(zu)(zu)(zu)，即勵磁(ci)繞組(zu)(zu)(zu)和(he)(he)控(kong)制繞組(zu)(zu)(zu)，兩(liang)個繞組(zu)(zu)(zu)在(zai)空間(jian)相(xiang)(xiang)差(cha)90°電(dian)(dian)角度(du)。固(gu)定和(he)(he)保護(hu)定子(zi)(zi)(zi)的(de)(de)機(ji)座一般用(yong)硬鋁或不銹鋼制成。籠型轉(zhuan)(zhuan)子(zi)(zi)(zi)交(jiao)(jiao)流(liu)伺(si)服(fu)(fu)電(dian)(dian)機(ji)的(de)(de)轉(zhuan)(zhuan)子(zi)(zi)(zi)和(he)(he)普通三相(xiang)(xiang)籠式電(dian)(dian)機(ji)相(xiang)(xiang)同。杯(bei)形轉(zhuan)(zhuan)子(zi)(zi)(zi)交(jiao)(jiao)流(liu)伺(si)服(fu)(fu)電(dian)(dian)機(ji)的(de)(de)結(jie)(jie)構由(you)外定子(zi)(zi)(zi)，杯(bei)形轉(zhuan)(zhuan)子(zi)(zi)(zi)和(he)(he)內(nei)(nei)定子(zi)(zi)(zi)三部分組(zu)(zu)(zu)成。它的(de)(de)外定子(zi)(zi)(zi)和(he)(he)籠型轉(zhuan)(zhuan)子(zi)(zi)(zi)交(jiao)(jiao)流(liu)伺(si)服(fu)(fu)電(dian)(dian)機(ji)相(xiang)(xiang)同，轉(zhuan)(zhuan)子(zi)(zi)(zi)則由(you)非磁(ci)性導電(dian)(dian)材料（如銅或鋁）制成空心杯(bei)形狀(zhuang)，杯(bei)子(zi)(zi)(zi)底部固(gu)定在(zai)轉(zhuan)(zhuan)軸7上(shang)。空心杯(bei)的(de)(de)壁(bi)很(hen)(hen)薄（小于0.5mm），因此轉(zhuan)(zhuan)動(dong)慣量很(hen)(hen)小。內(nei)(nei)定子(zi)(zi)(zi)由(you)硅鋼片(pian)疊壓而成，固(gu)定在(zai)一個端蓋上(shang)，內(nei)(nei)定子(zi)(zi)(zi)上(shang)沒(mei)有(you)(you)繞組(zu)(zu)(zu)，僅(jin)作磁(ci)路(lu)用(yong)。電(dian)(dian)機(ji)工作時，內(nei)(nei)﹑外定子(zi)(zi)(zi)都不動(dong)，只(zhi)有(you)(you)杯(bei)形轉(zhuan)(zhuan)子(zi)(zi)(zi)在(zai)內(nei)(nei)、外定子(zi)(zi)(zi)之間(jian)的(de)(de)氣隙中轉(zhuan)(zhuan)動(dong)。對于輸(shu)出功率(lv)較(jiao)小的(de)(de)交(jiao)(jiao)流(liu)伺(si)服(fu)(fu)電(dian)(dian)機(ji)，常(chang)將勵磁(ci)繞組(zu)(zu)(zu)和(he)(he)控(kong)制繞組(zu)(zu)(zu)分別安(an)放在(zai)內(nei)(nei)、外定子(zi)(zi)(zi)鐵心的(de)(de)槽(cao)內(nei)(nei)。
電(dian)機主要部件包(bao)括：1、機座(zuo)；2、鐵心；3、繞組；4、端蓋(gai)；5、軸承；6、離心開關或起動繼(ji)電(dian)器和PTC起動器；7、銘牌。
1機座
機(ji)(ji)座結構(gou)隨(sui)電(dian)動(dong)機(ji)(ji)冷卻方式(shi)、防護型式(shi)、安裝方式(shi)和用(yong)(yong)途而異。按(an)其材料分類，有鑄(zhu)鐵(tie)、鑄(zhu)鋁和鋼(gang)板結構(gou)等幾種。鑄(zhu)鐵(tie)機(ji)(ji)座，帶有散熱筋。機(ji)(ji)座與端蓋聯接，用(yong)(yong)螺栓緊(jin)固。鑄(zhu)鋁機(ji)(ji)座一(yi)般不帶有散熱筋。鋼(gang)板結構(gou)機(ji)(ji)座，是由(you)厚為1.5-2.5毫(hao)米的(de)(de)(de)(de)薄鋼(gang)板卷制、焊接而成，再焊上鋼(gang)板沖壓(ya)件的(de)(de)(de)(de)底腳。有的(de)(de)(de)(de)專(zhuan)用(yong)(yong)電(dian)動(dong)機(ji)(ji)的(de)(de)(de)(de)機(ji)(ji)座相(xiang)當特殊，如電(dian)冰(bing)箱的(de)(de)(de)(de)電(dian)動(dong)機(ji)(ji)，它通常與壓(ya)縮(suo)機(ji)(ji)一(yi)起(qi)裝在一(yi)個密封(feng)的(de)(de)(de)(de)罐子(zi)里。而洗衣機(ji)(ji)的(de)(de)(de)(de)電(dian)動(dong)機(ji)(ji)，包括甩干機(ji)(ji)的(de)(de)(de)(de)電(dian)動(dong)機(ji)(ji)，均無機(ji)(ji)座，端蓋直接固定(ding)(ding)在定(ding)(ding)子(zi)鐵(tie)心上。
2鐵心
鐵(tie)心(xin)(xin)包(bao)括定(ding)子(zi)鐵(tie)心(xin)(xin)和轉子(zi)鐵(tie)心(xin)(xin)，作用(yong)與三相異步電(dian)動機(ji)一樣，是用(yong)來構成電(dian)動機(ji)的(de)磁路。
3繞組
單相異步電動機定子(zi)繞組(zu)(zu)常(chang)做成(cheng)兩相：主繞組(zu)(zu)（工作繞組(zu)(zu)）和副繞組(zu)(zu)（啟(qi)動繞組(zu)(zu)）。兩種繞組(zu)(zu)的(de)中軸線(xian)錯開(kai)一(yi)定的(de)電角度。目的(de)是為了改善(shan)啟(qi)動性能和運行性能。定子(zi)繞組(zu)(zu)多采用(yong)高(gao)強度聚(ju)脂漆包線(xian)繞制。
轉子繞組(zu)一(yi)般采用籠型繞組(zu)。常用鋁壓鑄而成(cheng)。
4端蓋
相(xiang)應于不同的機座材料、端(duan)蓋也有鑄鐵件、鑄鋁件和鋼板沖壓件。
5軸承
軸承有滾(gun)珠(zhu)軸承和(he)含油軸承。
6離心開關或起動繼電器和PTC起動器
（1）離心開關
在(zai)單相異(yi)步(bu)(bu)電(dian)動(dong)(dong)(dong)(dong)(dong)機中(zhong)，除了(le)電(dian)容運(yun)轉電(dian)動(dong)(dong)(dong)(dong)(dong)機外，在(zai)起(qi)(qi)(qi)動(dong)(dong)(dong)(dong)(dong)過程中(zhong)，當轉子轉速(su)達到(dao)同步(bu)(bu)轉速(su)的70%左右時(shi)，常借助于離(li)心開(kai)(kai)關，切(qie)除單相電(dian)阻起(qi)(qi)(qi)動(dong)(dong)(dong)(dong)(dong)異(yi)步(bu)(bu)電(dian)動(dong)(dong)(dong)(dong)(dong)機和電(dian)容起(qi)(qi)(qi)動(dong)(dong)(dong)(dong)(dong)異(yi)步(bu)(bu)電(dian)動(dong)(dong)(dong)(dong)(dong)機的起(qi)(qi)(qi)動(dong)(dong)(dong)(dong)(dong)繞組，或切(qie)除電(dian)容起(qi)(qi)(qi)動(dong)(dong)(dong)(dong)(dong)及運(yun)轉異(yi)步(bu)(bu)電(dian)動(dong)(dong)(dong)(dong)(dong)機的起(qi)(qi)(qi)動(dong)(dong)(dong)(dong)(dong)電(dian)容器。離(li)心開(kai)(kai)關一(yi)般安(an)裝在(zai)軸伸端(duan)蓋(gai)的內(nei)側。
（2）起動繼電器
有些電(dian)(dian)(dian)(dian)動(dong)(dong)機(ji)(ji)，如電(dian)(dian)(dian)(dian)冰箱電(dian)(dian)(dian)(dian)動(dong)(dong)機(ji)(ji)，由于(yu)(yu)它(ta)與(yu)壓縮(suo)機(ji)(ji)組裝在(zai)(zai)一起，并(bing)放(fang)在(zai)(zai)密(mi)封(feng)的(de)(de)(de)罐子(zi)里，不便(bian)于(yu)(yu)安裝離心開關，就用起動(dong)(dong)繼電(dian)(dian)(dian)(dian)器(qi)(qi)代替。繼電(dian)(dian)(dian)(dian)器(qi)(qi)的(de)(de)(de)吸鐵線(xian)圈串(chuan)聯在(zai)(zai)主(zhu)繞(rao)組回路中，起動(dong)(dong)時，主(zhu)繞(rao)組電(dian)(dian)(dian)(dian)流很大，銜鐵動(dong)(dong)作(zuo)，使串(chuan)聯在(zai)(zai)副(fu)繞(rao)組回路中的(de)(de)(de)動(dong)(dong)合觸(chu)點(dian)閉合。于(yu)(yu)是(shi)副(fu)繞(rao)組接通，電(dian)(dian)(dian)(dian)動(dong)(dong)機(ji)(ji)處(chu)于(yu)(yu)兩相(xiang)繞(rao)組運行狀態。隨著轉子(zi)轉速上(shang)升，主(zhu)繞(rao)組電(dian)(dian)(dian)(dian)流不斷下降，吸引線(xian)圈的(de)(de)(de)吸力(li)(li)(li)下降。當到(dao)達一定的(de)(de)(de)轉速，電(dian)(dian)(dian)(dian)磁鐵的(de)(de)(de)吸力(li)(li)(li)小于(yu)(yu)觸(chu)點(dian)的(de)(de)(de)反(fan)作(zuo)用彈簧的(de)(de)(de)拉力(li)(li)(li)，觸(chu)點(dian)被(bei)打開，副(fu)繞(rao)組就脫離電(dian)(dian)(dian)(dian)源。
（3）PTC起動器
最新(xin)式的(de)(de)(de)啟動(dong)元(yuan)(yuan)件(jian)是(shi)“PTC”，它是(shi)一(yi)種能(neng)“通”或“斷(duan)”的(de)(de)(de)熱敏(min)(min)電(dian)(dian)阻(zu)(zu)。PTC熱敏(min)(min)電(dian)(dian)阻(zu)(zu)是(shi)一(yi)種新(xin)型的(de)(de)(de)半導體元(yuan)(yuan)件(jian)，可(ke)用作延時型起(qi)動(dong)開關。使用時，將PTC元(yuan)(yuan)件(jian)與電(dian)(dian)容起(qi)動(dong)或電(dian)(dian)阻(zu)(zu)起(qi)動(dong)電(dian)(dian)機的(de)(de)(de)副(fu)(fu)繞(rao)組串聯。在(zai)起(qi)動(dong)初期(qi)，因PTC熱敏(min)(min)電(dian)(dian)阻(zu)(zu)尚未發(fa)熱，阻(zu)(zu)值(zhi)很低，副(fu)(fu)繞(rao)組處于通路狀態，電(dian)(dian)機開始起(qi)動(dong)。隨著時間(jian)的(de)(de)(de)推(tui)移，電(dian)(dian)機的(de)(de)(de)轉速不(bu)斷(duan)增(zeng)加，PTC元(yuan)(yuan)件(jian)的(de)(de)(de)溫(wen)(wen)度因本(ben)身的(de)(de)(de)焦耳熱而上升，當(dang)超過居里點Tc（即電(dian)(dian)阻(zu)(zu)急劇增(zeng)加的(de)(de)(de)溫(wen)(wen)度點），電(dian)(dian)阻(zu)(zu)劇增(zeng)，副(fu)(fu)繞(rao)組電(dian)(dian)路相(xiang)當(dang)于斷(duan)開，但還有(you)一(yi)個很小(xiao)的(de)(de)(de)維持電(dian)(dian)流(liu)，并有(you)2-3瓦的(de)(de)(de)損(sun)耗，使PTC元(yuan)(yuan)件(jian)的(de)(de)(de)溫(wen)(wen)度維持在(zai)居里點Tc值(zhi)以上。當(dang)電(dian)(dian)機停止運行(xing)后，PTC元(yuan)(yuan)件(jian)溫(wen)(wen)度不(bu)斷(duan)下降，約(yue)2-3分鐘其電(dian)(dian)阻(zu)(zu)值(zhi)降到Tc點以下，這時有(you)可(ke)以重新(xin)啟動(dong)，這一(yi)時間(jian)正好是(shi)電(dian)(dian)冰箱(xiang)和空調機所(suo)規定的(de)(de)(de)兩次開機間(jian)的(de)(de)(de)停機時間(jian)。
PTC起動器的優點(dian)：無(wu)觸(chu)點(dian)、運行可靠、無(wu)噪(zao)無(wu)電火(huo)花，防(fang)(fang)火(huo)、防(fang)(fang)爆性(xing)能好。且耐振動、耐沖擊、體(ti)積小、重量(liang)輕、價格低。
7銘牌
包括：電(dian)(dian)機名稱、型號(hao)、標準編號(hao)、制造廠名、出廠編號(hao)、額定電(dian)(dian)壓(ya)、額定功(gong)率、額定電(dian)(dian)流、額定轉速、繞組接(jie)法、絕(jue)緣(yuan)等級等。