一、火花機的主要組成部件

火花機也稱為電火花(hua)加工機(ji)床(chuang)或EDM機(ji)床(chuang)，主(zhu)要組成(cheng)部件(jian)包括以下幾個部分(fen)：

1、機床主體

機床主(zhu)體是火花機的(de)基(ji)礎結構，它承載著所(suo)有的(de)工作部件和控(kong)制系(xi)統。主(zhu)體通常由(you)鑄鐵或鋼材制成，以確保穩定(ding)性(xing)和剛性(xing)。

2、主軸和電極夾持裝置

主軸是安裝和移動電極的部分，用于將電極精確定位在工件上方。電極(ji)夾持裝置(zhi)用(yong)于(yu)固定電極(ji)，并(bing)確保電極(ji)在加工過程中(zhong)保持穩定的位置(zhi)和角度。

3、工作臺和工件夾持裝置

工作臺用于支撐和移動工件，以便在加工過程中精確定位工件。工(gong)件夾持(chi)裝置用于(yu)固定工(gong)件，防止(zhi)在(zai)加工(gong)過程中(zhong)發(fa)生移(yi)動或(huo)振動。

4、電源和控制系統

電源系統為火花機提供所需的電壓和電流，用于產生電火花。控制系統是火花(hua)機(ji)的核心部分，它控制電極(ji)和工作臺的運動，以(yi)及(ji)電源的通斷(duan)，確保(bao)加工過程(cheng)的精(jing)確性和穩(wen)定性。控制系統通常包括計算機(ji)數控（CNC）系統，用于編程(cheng)和自動化加工過程(cheng)。

5、工作液循環系統

工(gong)(gong)(gong)作液在(zai)火花(hua)加工(gong)(gong)(gong)過(guo)程中起到(dao)冷卻、潤滑和清除(chu)加工(gong)(gong)(gong)廢屑的作用。工(gong)(gong)(gong)作液循環(huan)系統(tong)負責(ze)將工(gong)(gong)(gong)作液輸送到(dao)加工(gong)(gong)(gong)區域，并回(hui)收和過(guo)濾使(shi)用過(guo)的工(gong)(gong)(gong)作液。

6、電氣系統和傳感器

電氣系統為火花機提供電力和信號傳輸，確保各個部件的正常運行。傳感器用于(yu)監測加(jia)工(gong)過程中(zhong)的各種參數，如電(dian)極和(he)工(gong)作臺(tai)的位(wei)置、電(dian)流和(he)電(dian)壓等，以便及(ji)時(shi)調整和(he)控(kong)制加(jia)工(gong)過程。

7、安全防護裝置

火花機在工(gong)作過程中可能(neng)會產(chan)生火花和飛(fei)濺物，因此(ci)需(xu)要配(pei)備安全防護裝置，如防護罩、防護門和緊急停機按鈕(niu)等(deng)，以保護操作人員(yuan)的安全。

二、火花機的工作原理

進行電火花機加(jia)工(gong)(gong)(gong)時，工(gong)(gong)(gong)具(ju)電(dian)極(ji)(ji)和工(gong)(gong)(gong)件分別(bie)接(jie)脈沖電(dian)源(yuan)的兩極(ji)(ji)，并浸入(ru)工(gong)(gong)(gong)作液(ye)(ye)中(zhong)，或(huo)將工(gong)(gong)(gong)作液(ye)(ye)充入(ru)放電(dian)間(jian)隙(xi)。通過(guo)間(jian)隙(xi)自動控(kong)制系統控(kong)制工(gong)(gong)(gong)具(ju)電(dian)極(ji)(ji)向工(gong)(gong)(gong)件進給，當兩電(dian)極(ji)(ji)間(jian)的間(jian)隙(xi)達(da)到(dao)一定距離(li)時，兩電(dian)極(ji)(ji)上施加(jia)的脈沖電(dian)壓將工(gong)(gong)(gong)作液(ye)(ye)擊穿，產生火花放電(dian)。

在(zai)放電的(de)(de)微細通道中(zhong)瞬時(shi)(shi)集(ji)中(zhong)大(da)量的(de)(de)熱能，溫度(du)可高達(da)一(yi)萬(wan)攝氏度(du)以(yi)上，壓(ya)力也(ye)有(you)急(ji)劇變化，從而使這一(yi)點工(gong)作(zuo)表(biao)面局(ju)部微量的(de)(de)金(jin)屬材料立刻熔化、氣化，并(bing)爆炸式(shi)地(di)飛濺到工(gong)作(zuo)液(ye)中(zhong)，迅速冷凝，形成固(gu)體的(de)(de)金(jin)屬微粒(li)，被工(gong)作(zuo)液(ye)帶走。這時(shi)(shi)在(zai)工(gong)件(jian)表(biao)面上便留下(xia)一(yi)個微小的(de)(de)凹坑(keng)痕跡，放電短暫停歇(xie)，兩電極間(jian)工(gong)作(zuo)液(ye)恢復(fu)絕(jue)緣狀態。

緊接著，下一(yi)個脈沖(chong)電(dian)壓又(you)在(zai)兩電(dian)極(ji)相對接近(jin)的(de)另(ling)一(yi)點處(chu)擊穿，產生(sheng)(sheng)火花放電(dian)，重復上述過(guo)程。這(zhe)樣，雖然每個脈沖(chong)放電(dian)蝕除的(de)金屬量極(ji)少，但因每秒有成(cheng)千上萬次脈沖(chong)放電(dian)作用，就能蝕除較多的(de)金屬，具有一(yi)定的(de)生(sheng)(sheng)產率。

在(zai)保(bao)持工(gong)(gong)(gong)(gong)(gong)具(ju)(ju)(ju)電(dian)(dian)極(ji)(ji)與工(gong)(gong)(gong)(gong)(gong)件之(zhi)間恒(heng)定放電(dian)(dian)間隙(xi)的(de)條件下，一(yi)邊蝕除(chu)工(gong)(gong)(gong)(gong)(gong)件金屬，一(yi)邊使(shi)工(gong)(gong)(gong)(gong)(gong)具(ju)(ju)(ju)電(dian)(dian)極(ji)(ji)不斷(duan)地向工(gong)(gong)(gong)(gong)(gong)件進給，最后便加(jia)(jia)工(gong)(gong)(gong)(gong)(gong)出與工(gong)(gong)(gong)(gong)(gong)具(ju)(ju)(ju)電(dian)(dian)極(ji)(ji)形狀(zhuang)相(xiang)對應的(de)形狀(zhuang)來。因此，只要改變工(gong)(gong)(gong)(gong)(gong)具(ju)(ju)(ju)電(dian)(dian)極(ji)(ji)的(de)形狀(zhuang)和(he)工(gong)(gong)(gong)(gong)(gong)具(ju)(ju)(ju)電(dian)(dian)極(ji)(ji)與工(gong)(gong)(gong)(gong)(gong)件之(zhi)間的(de)相(xiang)對運動方式，就能加(jia)(jia)工(gong)(gong)(gong)(gong)(gong)出各種復雜的(de)型面。工(gong)(gong)(gong)(gong)(gong)具(ju)(ju)(ju)電(dian)(dian)極(ji)(ji)常用(yong)導電(dian)(dian)性良好、熔點較高、易加(jia)(jia)工(gong)(gong)(gong)(gong)(gong)的(de)耐電(dian)(dian)蝕材料，如(ru)銅(tong)、石(shi)墨、銅(tong)鎢(wu)合金和(he)鉬等。在(zai)加(jia)(jia)工(gong)(gong)(gong)(gong)(gong)過程(cheng)中(zhong)，工(gong)(gong)(gong)(gong)(gong)具(ju)(ju)(ju)電(dian)(dian)極(ji)(ji)也有損耗，但小于工(gong)(gong)(gong)(gong)(gong)件金屬的(de)蝕除(chu)量，甚(shen)至接近于無(wu)損耗。

工(gong)作液(ye)作為(wei)放電(dian)(dian)介質，在加工(gong)過(guo)(guo)程中還起著冷卻、排屑等作用(yong)(yong)。常(chang)用(yong)(yong)的(de)(de)(de)(de)(de)(de)工(gong)作液(ye)是粘度(du)較低(di)、閃點較高、性(xing)(xing)能(neng)(neng)穩(wen)定(ding)的(de)(de)(de)(de)(de)(de)介質，如煤油(you)、去離子水(shui)和(he)乳化(hua)液(ye)等。電(dian)(dian)火(huo)花(hua)機是一(yi)種自激(ji)放電(dian)(dian)，其特(te)點如下(xia)：火(huo)花(hua)放電(dian)(dian)的(de)(de)(de)(de)(de)(de)兩個電(dian)(dian)極(ji)(ji)間在放電(dian)(dian)前具較高的(de)(de)(de)(de)(de)(de)電(dian)(dian)壓，當兩電(dian)(dian)極(ji)(ji)接近(jin)時(shi)，其間介質被擊(ji)穿后，隨即發生火(huo)花(hua)放電(dian)(dian)。伴隨擊(ji)穿過(guo)(guo)程，兩電(dian)(dian)極(ji)(ji)間的(de)(de)(de)(de)(de)(de)電(dian)(dian)阻急劇(ju)變小，兩極(ji)(ji)之間的(de)(de)(de)(de)(de)(de)電(dian)(dian)壓也隨之急劇(ju)變低(di)。火(huo)花(hua)通(tong)(tong)道必須在維持(chi)暫短的(de)(de)(de)(de)(de)(de)時(shi)間（通(tong)(tong)常(chang)為(wei)10-7-10-3s）后及(ji)時(shi)熄滅(mie)，才(cai)可(ke)保持(chi)火(huo)花(hua)放電(dian)(dian)的(de)(de)(de)(de)(de)(de)“冷極(ji)(ji)”特(te)性(xing)(xing)（即通(tong)(tong)道能(neng)(neng)量(liang)轉換的(de)(de)(de)(de)(de)(de)熱能(neng)(neng)來不及(ji)傳至電(dian)(dian)極(ji)(ji)縱深(shen)），使通(tong)(tong)道能(neng)(neng)量(liang)作用(yong)(yong)于極(ji)(ji)小范(fan)圍。通(tong)(tong)道能(neng)(neng)量(liang)的(de)(de)(de)(de)(de)(de)作用(yong)(yong)，可(ke)使電(dian)(dian)極(ji)(ji)局部被腐(fu)蝕。利用(yong)(yong)火(huo)花(hua)放電(dian)(dian)時(shi)產生的(de)(de)(de)(de)(de)(de)腐(fu)蝕現象(xiang)對材料進行(xing)尺寸加工(gong)的(de)(de)(de)(de)(de)(de)方法(fa)，叫電(dian)(dian)火(huo)花(hua)機加工(gong)。