一、火花機的主要組成部件

火花機也稱(cheng)為電火花(hua)加工(gong)機床(chuang)或EDM機床(chuang)，主要組成部件包括(kuo)以下幾個部分：

1、機床主體

機床主體是火花機的(de)基礎(chu)結構，它承載著所(suo)有的(de)工作部件和(he)控制系統。主體通常(chang)由鑄鐵或(huo)鋼材制成，以確保穩定性和(he)剛性。

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)極夾持裝置(zhi)用(yong)于(yu)固(gu)定電(dian)極，并確(que)保電(dian)極在加工過程中保持穩定的(de)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)件夾持裝置用于固定工(gong)件，防止(zhi)在加工(gong)過程中(zhong)發生(sheng)移動(dong)或振(zhen)動(dong)。

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(tong)是火花機(ji)的(de)核心部分，它(ta)控制電極和工作臺的(de)運動(dong)，以(yi)及電源的(de)通斷(duan)，確(que)保加工過程的(de)精確(que)性和穩(wen)定性。控制系統(tong)通常包括(kuo)計(ji)算機(ji)數(shu)控（CNC）系統(tong)，用于編程和自動(dong)化加工過程。

5、工作液循環系統

工(gong)(gong)(gong)(gong)作液(ye)在(zai)火花加工(gong)(gong)(gong)(gong)過程中起到冷卻、潤滑和(he)清除加工(gong)(gong)(gong)(gong)廢屑(xie)的作用(yong)。工(gong)(gong)(gong)(gong)作液(ye)循環(huan)系(xi)統負責將(jiang)工(gong)(gong)(gong)(gong)作液(ye)輸(shu)送到加工(gong)(gong)(gong)(gong)區域，并回收和(he)過濾使用(yong)過的工(gong)(gong)(gong)(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。傳感器用于(yu)監(jian)測(ce)加(jia)工過程中(zhong)的各種參數，如(ru)電(dian)極(ji)和(he)工作臺(tai)的位置(zhi)、電(dian)流和(he)電(dian)壓等(deng)，以便及時調(diao)整和(he)控(kong)制(zhi)加(jia)工過程。

7、安全防護裝置

火花(hua)機在工作過程(cheng)中可(ke)能會產(chan)生火花(hua)和飛濺(jian)物，因此需要(yao)配備安全防護(hu)裝置，如防護(hu)罩、防護(hu)門(men)和緊急停機按鈕等，以保(bao)護(hu)操(cao)作人(ren)員的安全。

二、火花機的工作原理

進行電火花機加工(gong)(gong)時，工(gong)(gong)具電(dian)(dian)(dian)(dian)極(ji)和工(gong)(gong)件分別接脈沖(chong)電(dian)(dian)(dian)(dian)源的兩(liang)(liang)極(ji)，并(bing)浸入工(gong)(gong)作液(ye)中，或將(jiang)工(gong)(gong)作液(ye)充入放(fang)電(dian)(dian)(dian)(dian)間隙。通過間隙自(zi)動控(kong)制系統(tong)控(kong)制工(gong)(gong)具電(dian)(dian)(dian)(dian)極(ji)向工(gong)(gong)件進給，當兩(liang)(liang)電(dian)(dian)(dian)(dian)極(ji)間的間隙達到一定距離時，兩(liang)(liang)電(dian)(dian)(dian)(dian)極(ji)上(shang)施加的脈沖(chong)電(dian)(dian)(dian)(dian)壓將(jiang)工(gong)(gong)作液(ye)擊穿，產生火花放(fang)電(dian)(dian)(dian)(dian)。

在(zai)放電(dian)的(de)(de)微細通(tong)道中瞬時集中大(da)量(liang)(liang)的(de)(de)熱能，溫度(du)可高達一(yi)萬攝氏度(du)以上，壓力(li)也(ye)有急劇變化(hua)(hua)，從而使這一(yi)點工作(zuo)表面局部微量(liang)(liang)的(de)(de)金屬材料(liao)立(li)刻熔(rong)化(hua)(hua)、氣化(hua)(hua)，并爆炸(zha)式地飛(fei)濺到工作(zuo)液(ye)中，迅速冷凝，形成固體(ti)的(de)(de)金屬微粒，被(bei)工作(zuo)液(ye)帶走。這時在(zai)工件表面上便留下一(yi)個微小的(de)(de)凹坑痕跡，放電(dian)短暫停歇，兩(liang)電(dian)極間工作(zuo)液(ye)恢復絕(jue)緣狀態。

緊接(jie)著，下一個(ge)(ge)脈沖電(dian)(dian)(dian)壓又在(zai)兩電(dian)(dian)(dian)極(ji)相(xiang)對接(jie)近(jin)的(de)另一點處擊穿，產(chan)(chan)生火花(hua)放(fang)電(dian)(dian)(dian)，重復上(shang)述過(guo)程。這(zhe)樣，雖然每(mei)個(ge)(ge)脈沖放(fang)電(dian)(dian)(dian)蝕除的(de)金(jin)屬(shu)量極(ji)少(shao)，但(dan)因每(mei)秒有成千上(shang)萬次脈沖放(fang)電(dian)(dian)(dian)作(zuo)用(yong)，就能蝕除較多的(de)金(jin)屬(shu)，具有一定的(de)生產(chan)(chan)率。

在(zai)保持工(gong)(gong)(gong)具(ju)(ju)電(dian)(dian)(dian)極(ji)(ji)與(yu)工(gong)(gong)(gong)件(jian)(jian)之間恒定放電(dian)(dian)(dian)間隙(xi)的(de)(de)條件(jian)(jian)下，一(yi)邊(bian)蝕除工(gong)(gong)(gong)件(jian)(jian)金(jin)屬(shu)，一(yi)邊(bian)使工(gong)(gong)(gong)具(ju)(ju)電(dian)(dian)(dian)極(ji)(ji)不斷地向工(gong)(gong)(gong)件(jian)(jian)進給，最后便加(jia)工(gong)(gong)(gong)出(chu)與(yu)工(gong)(gong)(gong)具(ju)(ju)電(dian)(dian)(dian)極(ji)(ji)形(xing)狀相對(dui)(dui)應的(de)(de)形(xing)狀來。因此，只要改變工(gong)(gong)(gong)具(ju)(ju)電(dian)(dian)(dian)極(ji)(ji)的(de)(de)形(xing)狀和(he)工(gong)(gong)(gong)具(ju)(ju)電(dian)(dian)(dian)極(ji)(ji)與(yu)工(gong)(gong)(gong)件(jian)(jian)之間的(de)(de)相對(dui)(dui)運動方式，就(jiu)能加(jia)工(gong)(gong)(gong)出(chu)各種復雜的(de)(de)型面。工(gong)(gong)(gong)具(ju)(ju)電(dian)(dian)(dian)極(ji)(ji)常用導電(dian)(dian)(dian)性良好(hao)、熔點較(jiao)高、易加(jia)工(gong)(gong)(gong)的(de)(de)耐(nai)電(dian)(dian)(dian)蝕材料，如(ru)銅、石墨、銅鎢(wu)合金(jin)和(he)鉬等。在(zai)加(jia)工(gong)(gong)(gong)過(guo)程中，工(gong)(gong)(gong)具(ju)(ju)電(dian)(dian)(dian)極(ji)(ji)也有損(sun)耗，但小于工(gong)(gong)(gong)件(jian)(jian)金(jin)屬(shu)的(de)(de)蝕除量，甚至接近于無損(sun)耗。

工(gong)作液作為放(fang)(fang)(fang)電(dian)(dian)(dian)介(jie)質，在(zai)(zai)(zai)加工(gong)過程中還起著冷卻、排屑等作用(yong)(yong)(yong)。常用(yong)(yong)(yong)的(de)(de)工(gong)作液是粘度較(jiao)低、閃點(dian)較(jiao)高(gao)、性(xing)能穩定的(de)(de)介(jie)質，如煤油(you)、去(qu)離子水(shui)和乳化液等。電(dian)(dian)(dian)火(huo)花(hua)(hua)機是一種自激(ji)放(fang)(fang)(fang)電(dian)(dian)(dian)，其特點(dian)如下：火(huo)花(hua)(hua)放(fang)(fang)(fang)電(dian)(dian)(dian)的(de)(de)兩個電(dian)(dian)(dian)極(ji)(ji)間在(zai)(zai)(zai)放(fang)(fang)(fang)電(dian)(dian)(dian)前具(ju)較(jiao)高(gao)的(de)(de)電(dian)(dian)(dian)壓，當(dang)兩電(dian)(dian)(dian)極(ji)(ji)接近時(shi)，其間介(jie)質被(bei)擊(ji)穿后，隨(sui)即發(fa)生(sheng)(sheng)火(huo)花(hua)(hua)放(fang)(fang)(fang)電(dian)(dian)(dian)。伴隨(sui)擊(ji)穿過程，兩電(dian)(dian)(dian)極(ji)(ji)間的(de)(de)電(dian)(dian)(dian)阻急劇(ju)變小，兩極(ji)(ji)之間的(de)(de)電(dian)(dian)(dian)壓也隨(sui)之急劇(ju)變低。火(huo)花(hua)(hua)通(tong)(tong)道必須在(zai)(zai)(zai)維持暫短的(de)(de)時(shi)間（通(tong)(tong)常為10-7-10-3s）后及(ji)時(shi)熄滅(mie)，才可(ke)保持火(huo)花(hua)(hua)放(fang)(fang)(fang)電(dian)(dian)(dian)的(de)(de)“冷極(ji)(ji)”特性(xing)（即通(tong)(tong)道能量(liang)(liang)轉換的(de)(de)熱能來不(bu)及(ji)傳至電(dian)(dian)(dian)極(ji)(ji)縱深），使通(tong)(tong)道能量(liang)(liang)作用(yong)(yong)(yong)于極(ji)(ji)小范圍。通(tong)(tong)道能量(liang)(liang)的(de)(de)作用(yong)(yong)(yong)，可(ke)使電(dian)(dian)(dian)極(ji)(ji)局部被(bei)腐蝕。利用(yong)(yong)(yong)火(huo)花(hua)(hua)放(fang)(fang)(fang)電(dian)(dian)(dian)時(shi)產生(sheng)(sheng)的(de)(de)腐蝕現象對材料進行尺寸加工(gong)的(de)(de)方(fang)法，叫電(dian)(dian)(dian)火(huo)花(hua)(hua)機加工(gong)。