一、火花機的主要組成部件

火花機也稱為電火花加工機床(chuang)或(huo)EDM機床(chuang)，主(zhu)要(yao)組(zu)成部件包括以下幾(ji)個(ge)部分(fen)：

1、機床主體

機床主體是火花機的基礎(chu)結構(gou)，它承載著所有的工(gong)作部(bu)件和控制(zhi)系(xi)統。主體通常由(you)鑄(zhu)鐵(tie)或(huo)鋼材制(zhi)成，以確保穩定性(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(dian)極夾持裝(zhuang)置用于固定(ding)(ding)電(dian)極，并確保電(dian)極在加工(gong)過(guo)程中保持穩定(ding)(ding)的位置和(he)角度(du)。

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(jian)夾(jia)持裝(zhuang)置用于固定工(gong)件(jian)，防止在(zai)加工(gong)過程中發生移(yi)動或振(zhen)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(zhi)系(xi)統(tong)是火花機(ji)的(de)(de)核心部(bu)分，它控制(zhi)電極和工(gong)作臺(tai)的(de)(de)運動，以及(ji)電源的(de)(de)通斷，確(que)(que)保加工(gong)過(guo)程的(de)(de)精(jing)確(que)(que)性和穩定性。控制(zhi)系(xi)統(tong)通常包括計算機(ji)數控（CNC）系(xi)統(tong)，用于編程和自(zi)動化加工(gong)過(guo)程。

5、工作液循環系統

工(gong)作液(ye)在火花加工(gong)過程(cheng)中起到(dao)冷卻、潤滑和清(qing)除加工(gong)廢屑的作用。工(gong)作液(ye)循環系統負責將工(gong)作液(ye)輸送到(dao)加工(gong)區域，并回收和過濾使(shi)用過的工(gong)作液(ye)。

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(gan)器用于監(jian)測加工過程中的(de)(de)各(ge)種參數，如電極和工作臺的(de)(de)位置(zhi)、電流和電壓等，以便及時調(diao)整和控(kong)制加工過程。

7、安全防護裝置

火(huo)花(hua)機在工作過程中可能會產生火(huo)花(hua)和飛濺物，因此需要配備安(an)全(quan)防護(hu)裝置，如(ru)防護(hu)罩、防護(hu)門(men)和緊急停機按鈕等(deng)，以(yi)保護(hu)操作人員的安(an)全(quan)。

二、火花機的工作原理

進行電火花機加(jia)工(gong)時，工(gong)具(ju)電(dian)(dian)極和工(gong)件分(fen)別接脈沖電(dian)(dian)源的兩極，并浸(jin)入(ru)工(gong)作(zuo)液(ye)中(zhong)，或將(jiang)工(gong)作(zuo)液(ye)充(chong)入(ru)放電(dian)(dian)間隙(xi)。通(tong)過間隙(xi)自動控(kong)制(zhi)(zhi)系統(tong)控(kong)制(zhi)(zhi)工(gong)具(ju)電(dian)(dian)極向工(gong)件進(jin)給，當兩電(dian)(dian)極間的間隙(xi)達到一定距離時，兩電(dian)(dian)極上施(shi)加(jia)的脈沖電(dian)(dian)壓將(jiang)工(gong)作(zuo)液(ye)擊穿，產生火花(hua)放電(dian)(dian)。

在(zai)放電(dian)的(de)微(wei)細通道中瞬時(shi)集中大量(liang)的(de)熱能，溫度可高達一(yi)萬攝氏度以上，壓力(li)也有急劇(ju)變化，從而使這一(yi)點工(gong)作(zuo)表(biao)面局部微(wei)量(liang)的(de)金屬材料立刻(ke)熔化、氣化，并爆炸式(shi)地(di)飛濺(jian)到工(gong)作(zuo)液中，迅速冷凝(ning)，形成固體的(de)金屬微(wei)粒(li)，被工(gong)作(zuo)液帶走。這時(shi)在(zai)工(gong)件表(biao)面上便留下一(yi)個微(wei)小的(de)凹坑(keng)痕跡，放電(dian)短暫停歇，兩(liang)電(dian)極間工(gong)作(zuo)液恢復絕緣狀態。

緊(jin)接著，下一(yi)個(ge)脈沖(chong)電(dian)(dian)壓又在兩(liang)電(dian)(dian)極相對接近的(de)另一(yi)點處擊穿，產生火花(hua)放電(dian)(dian)，重(zhong)復上(shang)述過程。這樣，雖然每個(ge)脈沖(chong)放電(dian)(dian)蝕(shi)除(chu)的(de)金(jin)屬(shu)量極少(shao)，但因每秒(miao)有成千上(shang)萬次脈沖(chong)放電(dian)(dian)作用，就能蝕(shi)除(chu)較(jiao)多的(de)金(jin)屬(shu)，具有一(yi)定(ding)的(de)生產率。

在(zai)(zai)保持工(gong)(gong)(gong)(gong)具(ju)電(dian)極與工(gong)(gong)(gong)(gong)件(jian)(jian)之間(jian)恒定(ding)放(fang)電(dian)間(jian)隙的條(tiao)件(jian)(jian)下，一(yi)邊蝕(shi)除工(gong)(gong)(gong)(gong)件(jian)(jian)金(jin)屬(shu)，一(yi)邊使工(gong)(gong)(gong)(gong)具(ju)電(dian)極不斷地(di)向工(gong)(gong)(gong)(gong)件(jian)(jian)進(jin)給，最(zui)后便加(jia)工(gong)(gong)(gong)(gong)出(chu)與工(gong)(gong)(gong)(gong)具(ju)電(dian)極形(xing)狀(zhuang)相對(dui)應的形(xing)狀(zhuang)來(lai)。因此，只(zhi)要改(gai)變(bian)工(gong)(gong)(gong)(gong)具(ju)電(dian)極的形(xing)狀(zhuang)和工(gong)(gong)(gong)(gong)具(ju)電(dian)極與工(gong)(gong)(gong)(gong)件(jian)(jian)之間(jian)的相對(dui)運動方式，就能加(jia)工(gong)(gong)(gong)(gong)出(chu)各種復雜的型面(mian)。工(gong)(gong)(gong)(gong)具(ju)電(dian)極常(chang)用導(dao)電(dian)性良(liang)好、熔點較高、易(yi)加(jia)工(gong)(gong)(gong)(gong)的耐電(dian)蝕(shi)材料，如銅、石墨、銅鎢(wu)合金(jin)和鉬等。在(zai)(zai)加(jia)工(gong)(gong)(gong)(gong)過程(cheng)中，工(gong)(gong)(gong)(gong)具(ju)電(dian)極也(ye)有損耗，但小于工(gong)(gong)(gong)(gong)件(jian)(jian)金(jin)屬(shu)的蝕(shi)除量，甚至接(jie)近于無損耗。

工(gong)作液作為(wei)放(fang)(fang)(fang)電(dian)(dian)(dian)(dian)介質(zhi)(zhi)，在加(jia)工(gong)過(guo)(guo)程中還起著冷(leng)(leng)卻、排屑等(deng)作用(yong)。常用(yong)的(de)工(gong)作液是(shi)粘度較低(di)、閃點較高、性能(neng)穩定的(de)介質(zhi)(zhi)，如煤油、去離子水和乳(ru)化液等(deng)。電(dian)(dian)(dian)(dian)火(huo)(huo)(huo)花(hua)(hua)(hua)機(ji)是(shi)一種自激(ji)放(fang)(fang)(fang)電(dian)(dian)(dian)(dian)，其特(te)點如下：火(huo)(huo)(huo)花(hua)(hua)(hua)放(fang)(fang)(fang)電(dian)(dian)(dian)(dian)的(de)兩個(ge)電(dian)(dian)(dian)(dian)極(ji)間在放(fang)(fang)(fang)電(dian)(dian)(dian)(dian)前(qian)具較高的(de)電(dian)(dian)(dian)(dian)壓，當兩電(dian)(dian)(dian)(dian)極(ji)接近時(shi)(shi)，其間介質(zhi)(zhi)被擊(ji)穿(chuan)(chuan)后(hou)，隨即(ji)發(fa)生火(huo)(huo)(huo)花(hua)(hua)(hua)放(fang)(fang)(fang)電(dian)(dian)(dian)(dian)。伴隨擊(ji)穿(chuan)(chuan)過(guo)(guo)程，兩電(dian)(dian)(dian)(dian)極(ji)間的(de)電(dian)(dian)(dian)(dian)阻急劇(ju)變小(xiao)，兩極(ji)之(zhi)(zhi)間的(de)電(dian)(dian)(dian)(dian)壓也隨之(zhi)(zhi)急劇(ju)變低(di)。火(huo)(huo)(huo)花(hua)(hua)(hua)通(tong)(tong)道(dao)(dao)必(bi)須在維持暫短(duan)的(de)時(shi)(shi)間（通(tong)(tong)常為(wei)10-7-10-3s）后(hou)及時(shi)(shi)熄滅(mie)，才可保(bao)持火(huo)(huo)(huo)花(hua)(hua)(hua)放(fang)(fang)(fang)電(dian)(dian)(dian)(dian)的(de)“冷(leng)(leng)極(ji)”特(te)性（即(ji)通(tong)(tong)道(dao)(dao)能(neng)量轉換的(de)熱能(neng)來不及傳至電(dian)(dian)(dian)(dian)極(ji)縱深），使(shi)(shi)通(tong)(tong)道(dao)(dao)能(neng)量作用(yong)于極(ji)小(xiao)范圍。通(tong)(tong)道(dao)(dao)能(neng)量的(de)作用(yong)，可使(shi)(shi)電(dian)(dian)(dian)(dian)極(ji)局(ju)部被腐(fu)蝕。利用(yong)火(huo)(huo)(huo)花(hua)(hua)(hua)放(fang)(fang)(fang)電(dian)(dian)(dian)(dian)時(shi)(shi)產生的(de)腐(fu)蝕現象對材料進行尺寸加(jia)工(gong)的(de)方(fang)法，叫電(dian)(dian)(dian)(dian)火(huo)(huo)(huo)花(hua)(hua)(hua)機(ji)加(jia)工(gong)。