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 一(yi)、按加工工藝方法分類     

1．金屬(shu)切削類數控機床 
     與傳統的車(che)、銑(xian)、鉆、磨、齒(chi)輪加工相對應的數控(kong)(kong)(kong)(kong)(kong)機床有(you)數控(kong)(kong)(kong)(kong)(kong)車(che)床、數控(kong)(kong)(kong)(kong)(kong)銑(xian)床、數控(kong)(kong)(kong)(kong)(kong)鉆床、數控(kong)(kong)(kong)(kong)(kong)磨床、數控(kong)(kong)(kong)(kong)(kong)齒(chi)輪加工機床等(deng)。盡管(guan)這些數控(kong)(kong)(kong)(kong)(kong)機床在加工工藝(yi)方(fang)法上(shang)存在很大差別，具體的控(kong)(kong)(kong)(kong)(kong)制方(fang)式也各(ge)不相同，但機床的動(dong)作和運動(dong)都是數字化控(kong)(kong)(kong)(kong)(kong)制的，具有(you)較高的生產率和自(zi)動(dong)化程度。 
    在普(pu)通(tong)數控(kong)機(ji)床(chuang)(chuang)(chuang)加(jia)(jia)裝一(yi)個刀(dao)(dao)(dao)庫和(he)(he)換(huan)刀(dao)(dao)(dao)裝置就成為數控(kong)加(jia)(jia)工(gong)(gong)(gong)(gong)中(zhong)心機(ji)床(chuang)(chuang)(chuang)。加(jia)(jia)工(gong)(gong)(gong)(gong)中(zhong)心機(ji)床(chuang)(chuang)(chuang)進(jin)一(yi)步進(jin)步了普(pu)通(tong)數控(kong)機(ji)床(chuang)(chuang)(chuang)的(de)自動(dong)(dong)化程度和(he)(he)生產效(xiao)率(lv)(lv)。例如(ru)銑(xian)(xian)、鏜、鉆加(jia)(jia)工(gong)(gong)(gong)(gong)中(zhong)心，它是(shi)在數控(kong)銑(xian)(xian)床(chuang)(chuang)(chuang)基礎上增加(jia)(jia)了一(yi)個容量(liang)較大(da)的(de)刀(dao)(dao)(dao)庫和(he)(he)自動(dong)(dong)換(huan)刀(dao)(dao)(dao)裝置形成的(de)，工(gong)(gong)(gong)(gong)件(jian)一(yi)次裝夾(jia)后，可以對箱(xiang)體零件(jian)的(de)四面(mian)甚至(zhi)五面(mian)大(da)部分加(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)序進(jin)行(xing)銑(xian)(xian)、鏜、鉆、擴、鉸以及攻螺紋(wen)等多工(gong)(gong)(gong)(gong)序加(jia)(jia)工(gong)(gong)(gong)(gong)，特別適合箱(xiang)體類零件(jian)的(de)加(jia)(jia)工(gong)(gong)(gong)(gong)。加(jia)(jia)工(gong)(gong)(gong)(gong)中(zhong)心機(ji)床(chuang)(chuang)(chuang)可以有效(xiao)地(di)避免由于工(gong)(gong)(gong)(gong)件(jian)多次安裝造(zao)成的(de)定位誤差，減(jian)少(shao)了機(ji)床(chuang)(chuang)(chuang)的(de)臺數和(he)(he)占地(di)面(mian)積(ji)，縮(suo)短了輔助時間，大(da)大(da)進(jin)步了生產效(xiao)率(lv)(lv)和(he)(he)加(jia)(jia)工(gong)(gong)(gong)(gong)質量(liang)。 
2．特(te)種(zhong)加工類數控(kong)機(ji)床 
     除了切削加(jia)工數(shu)控(kong)機(ji)床(chuang)以外，數(shu)控(kong)技術也大(da)量用于數(shu)控(kong)電火花(hua)(hua)線切割機(ji)床(chuang)、數(shu)控(kong)電火花(hua)(hua)成型機(ji)床(chuang)、數(shu)控(kong)等離子弧切割機(ji)床(chuang)、數(shu)控(kong)火焰切割機(ji)床(chuang)以及(ji)數(shu)控(kong)激光加(jia)工機(ji)床(chuang)等。 
3．板(ban)材加(jia)工類數控(kong)機床 
    常見的應用于金屬板材加(jia)工的數控機床有數控壓力機、數控剪板機和(he)數控折彎機等。 
    近年(nian)來，其它機(ji)(ji)械(xie)設(she)備中也大量采用了(le)數(shu)控技術，如(ru)數(shu)控多坐標丈量機(ji)(ji)、自動繪圖機(ji)(ji)及產業機(ji)(ji)器人等。 
二、按控(kong)制運動軌跡(ji)分類(lei) 
1． 點位控(kong)制數控(kong)機床 
      點位控(kong)制數控(kong)機床的特點是機床移動(dong)(dong)部件只能實現由一個位置到另一個位置的精確定位，在移動(dong)(dong)和定位過程中(zhong)不進行(xing)任(ren)何(he)加工(gong)。機床數控(kong)系(xi)統只控(kong)制行(xing)程終點的坐(zuo)標(biao)值，不控(kong)制點與點之(zhi)間的運(yun)(yun)動(dong)(dong)軌跡，因此幾個坐(zuo)標(biao)軸之(zhi)間的運(yun)(yun)動(dong)(dong)無任(ren)何(he)聯系(xi)。可以(yi)幾個坐(zuo)標(biao)同時向目標(biao)點運(yun)(yun)動(dong)(dong)，也可以(yi)各個坐(zuo)標(biao)單獨依(yi)次運(yun)(yun)動(dong)(dong)。 
      這類數(shu)(shu)(shu)控(kong)機(ji)床主要有數(shu)(shu)(shu)控(kong)坐標(biao)鏜床、數(shu)(shu)(shu)控(kong)鉆床、數(shu)(shu)(shu)控(kong)沖床、數(shu)(shu)(shu)控(kong)點焊機(ji)等。點位控(kong)制數(shu)(shu)(shu)控(kong)機(ji)床的數(shu)(shu)(shu)控(kong)裝置稱為(wei)點位數(shu)(shu)(shu)控(kong)裝置。 
 2．直線(xian)控(kong)制(zhi)數控(kong)機床 
      直(zhi)(zhi)線(xian)控制(zhi)(zhi)數控機(ji)床可控制(zhi)(zhi)刀具或(huo)工作臺(tai)以(yi)適當的進給速(su)度(du)，沿著(zhu)平行于(yu)坐(zuo)標軸的方向進行直(zhi)(zhi)線(xian)移動和切削加(jia)工，進給速(su)度(du)根據切削條件可在一定范圍(wei)內變化。 
      直(zhi)線控(kong)制(zhi)的(de)簡易(yi)數控(kong)車床(chuang)(chuang)，只有(you)兩個坐(zuo)標(biao)軸，可(ke)加(jia)工門路(lu)軸。直(zhi)線控(kong)制(zhi)的(de)數控(kong)銑床(chuang)(chuang)，有(you)三個坐(zuo)標(biao)軸，可(ke)用于(yu)平(ping)面(mian)的(de)銑削加(jia)工。現(xian)代組合機(ji)床(chuang)(chuang)采(cai)用數控(kong)進(jin)(jin)給伺服系統，驅動動力頭帶有(you)多軸箱的(de)軸向(xiang)進(jin)(jin)給進(jin)(jin)行鉆(zhan)鏜(tang)加(jia)工，它也(ye)可(ke)算是一(yi)種直(zhi)線控(kong)制(zhi)數控(kong)機(ji)床(chuang)(chuang)。 
       數(shu)控(kong)鏜(tang)銑(xian)床(chuang)、加工中心等(deng)機床(chuang)，它的(de)各個坐標(biao)方向的(de)進給運動的(de)速度能(neng)在一定范(fan)圍內(nei)進行調整，兼有點(dian)位(wei)和直線(xian)控(kong)制加工的(de)功(gong)能(neng)，這類機床(chuang)應該稱為點(dian)位(wei)/直線(xian)控(kong)制的(de)數(shu)控(kong)機床(chuang)。 
3． 輪(lun)廓控(kong)制數(shu)控(kong)機(ji)床(chuang) 
       輪(lun)廓(kuo)(kuo)控(kong)制數控(kong)機床能(neng)夠對兩個或兩個以上(shang)運(yun)動(dong)的(de)(de)位移(yi)及速度進(jin)行連續相關的(de)(de)控(kong)制，使合成的(de)(de)平(ping)面或空間的(de)(de)運(yun)動(dong)軌跡(ji)能(neng)滿足(zu)零(ling)件(jian)輪(lun)廓(kuo)(kuo)的(de)(de)要(yao)求。它不僅(jin)能(neng)控(kong)制機床移(yi)動(dong)部件(jian)的(de)(de)出發(fa)點(dian)與終點(dian)坐(zuo)標，而且能(neng)控(kong)制整個加工(gong)輪(lun)廓(kuo)(kuo)每一點(dian)的(de)(de)速度和位移(yi)，將(jiang)工(gong)件(jian)加工(gong)成要(yao)求的(de)(de)輪(lun)廓(kuo)(kuo)外形。 
       常用(yong)的(de)數控(kong)(kong)(kong)車(che)床(chuang)(chuang)、數控(kong)(kong)(kong)銑床(chuang)(chuang)、數控(kong)(kong)(kong)磨床(chuang)(chuang)就是典型的(de)輪廓控(kong)(kong)(kong)制(zhi)數控(kong)(kong)(kong)機床(chuang)(chuang)。數控(kong)(kong)(kong)火(huo)焰切割機、電火(huo)花加工機床(chuang)(chuang)以及數控(kong)(kong)(kong)繪(hui)圖機等也采用(yong)了輪廓控(kong)(kong)(kong)制(zhi)系統。輪廓控(kong)(kong)(kong)制(zhi)系統的(de)結構要比點位/直線控(kong)(kong)(kong)系統更為復雜，在加工過(guo)程中需(xu)要不(bu)斷進行(xing)插補運算(suan)，然(ran)后進行(xing)相(xiang)應的(de)速度與位移控(kong)(kong)(kong)制(zhi)。 
      現(xian)(xian)在(zai)計算(suan)機數(shu)控裝置的(de)控制(zhi)功(gong)能(neng)均由軟件實現(xian)(xian)，增加輪廓控制(zhi)功(gong)能(neng)不會帶來本錢的(de)增加。因此，除少數(shu)專用控制(zhi)系(xi)統外，現(xian)(xian)代計算(suan)機數(shu)控裝置都具有輪廓控制(zhi)功(gong)能(neng)。 
三、按驅動裝置的特點分類 
1． 開環控(kong)制數控(kong)機(ji)床 
       這類控(kong)(kong)制的(de)數控(kong)(kong)機(ji)(ji)(ji)床(chuang)是其控(kong)(kong)制系統沒(mei)有位(wei)置檢測元件(jian)，伺(si)服驅(qu)動(dong)(dong)(dong)(dong)部件(jian)通(tong)常為(wei)反(fan)應式(shi)步(bu)進電(dian)(dian)動(dong)(dong)(dong)(dong)機(ji)(ji)(ji)或混合式(shi)伺(si)服步(bu)進電(dian)(dian)動(dong)(dong)(dong)(dong)機(ji)(ji)(ji)。數控(kong)(kong)系統每發(fa)出(chu)一個進給(gei)(gei)指(zhi)令(ling)，經驅(qu)動(dong)(dong)(dong)(dong)電(dian)(dian)路(lu)功(gong)率放大后，驅(qu)動(dong)(dong)(dong)(dong)步(bu)進電(dian)(dian)機(ji)(ji)(ji)旋轉(zhuan)一個角度，再經過齒輪減速裝(zhuang)置帶動(dong)(dong)(dong)(dong)絲杠旋轉(zhuan)，通(tong)過絲杠螺母機(ji)(ji)(ji)構轉(zhuan)換為(wei)移動(dong)(dong)(dong)(dong)部件(jian)的(de)直線位(wei)移。移動(dong)(dong)(dong)(dong)部件(jian)的(de)移動(dong)(dong)(dong)(dong)速度與(yu)位(wei)移量是由輸(shu)進脈沖(chong)(chong)(chong)的(de)頻率與(yu)脈沖(chong)(chong)(chong)數所決定的(de)。此(ci)類數控(kong)(kong)機(ji)(ji)(ji)床(chuang)的(de)信(xin)息流是單向(xiang)的(de)，即進給(gei)(gei)脈沖(chong)(chong)(chong)發(fa)出(chu)往后，實際移動(dong)(dong)(dong)(dong)值不再反(fan)饋回來，所以稱為(wei)開環控(kong)(kong)制數控(kong)(kong)機(ji)(ji)(ji)床(chuang)。 
       開環(huan)控(kong)(kong)制系(xi)統的數(shu)控(kong)(kong)機(ji)床(chuang)結構(gou)簡單，本錢較低。但是(shi)，系(xi)統對移(yi)動部件(jian)的實(shi)際位移(yi)量(liang)不進(jin)行(xing)監測，也(ye)不能進(jin)行(xing)誤差校正(zheng)。因此，步進(jin)電動機(ji)的失(shi)步、步距角(jiao)誤差、齒(chi)輪與絲杠(gang)等傳(chuan)動誤差都將影響被加工零件(jian)的精度(du)(du)。開環(huan)控(kong)(kong)制系(xi)統僅適用(yong)于(yu)加工精度(du)(du)要求不很高的中小型數(shu)控(kong)(kong)機(ji)床(chuang)，特別是(shi)簡易經(jing)濟(ji)型數(shu)控(kong)(kong)機(ji)床(chuang)。 
2． 閉環控制(zhi)數控機床 
       閉(bi)(bi)環控(kong)(kong)(kong)制(zhi)(zhi)數控(kong)(kong)(kong)機(ji)床(chuang)(chuang)是在機(ji)床(chuang)(chuang)移(yi)(yi)(yi)動(dong)(dong)部(bu)件(jian)上直接安裝(zhuang)直線(xian)位(wei)(wei)移(yi)(yi)(yi)檢(jian)測(ce)裝(zhuang)置(zhi)，直接對(dui)工(gong)作(zuo)(zuo)臺的(de)(de)(de)(de)實(shi)(shi)(shi)際(ji)位(wei)(wei)移(yi)(yi)(yi)進(jin)(jin)行(xing)(xing)檢(jian)測(ce)，將(jiang)(jiang)丈(zhang)量(liang)的(de)(de)(de)(de)實(shi)(shi)(shi)際(ji)位(wei)(wei)移(yi)(yi)(yi)值(zhi)(zhi)(zhi)(zhi)反(fan)饋(kui)(kui)到數控(kong)(kong)(kong)裝(zhuang)置(zhi)中(zhong)(zhong)，與(yu)輸進(jin)(jin)的(de)(de)(de)(de)指令(ling)位(wei)(wei)移(yi)(yi)(yi)值(zhi)(zhi)(zhi)(zhi)進(jin)(jin)行(xing)(xing)比(bi)較，用差(cha)值(zhi)(zhi)(zhi)(zhi)對(dui)機(ji)床(chuang)(chuang)進(jin)(jin)行(xing)(xing)控(kong)(kong)(kong)制(zhi)(zhi)，使(shi)移(yi)(yi)(yi)動(dong)(dong)部(bu)件(jian)按(an)照實(shi)(shi)(shi)際(ji)需要(yao)的(de)(de)(de)(de)位(wei)(wei)移(yi)(yi)(yi)量(liang)運動(dong)(dong)，終極實(shi)(shi)(shi)現移(yi)(yi)(yi)動(dong)(dong)部(bu)件(jian)的(de)(de)(de)(de)精確運動(dong)(dong)和(he)定位(wei)(wei)。從理論(lun)上講，閉(bi)(bi)環系(xi)(xi)統的(de)(de)(de)(de)運動(dong)(dong)精度(du)(du)主要(yao)取決于檢(jian)測(ce)裝(zhuang)置(zhi)的(de)(de)(de)(de)檢(jian)測(ce)精度(du)(du)，也與(yu)傳動(dong)(dong)鏈(lian)的(de)(de)(de)(de)誤差(cha)無關(guan)，因此其控(kong)(kong)(kong)制(zhi)(zhi)精度(du)(du)高。圖1-3所示的(de)(de)(de)(de)為(wei)(wei)閉(bi)(bi)環控(kong)(kong)(kong)制(zhi)(zhi)數控(kong)(kong)(kong)機(ji)床(chuang)(chuang)的(de)(de)(de)(de)系(xi)(xi)統框圖。圖中(zhong)(zhong)A為(wei)(wei)速度(du)(du)傳感(gan)器(qi)、C為(wei)(wei)直線(xian)位(wei)(wei)移(yi)(yi)(yi)傳感(gan)器(qi)。當位(wei)(wei)移(yi)(yi)(yi)指令(ling)值(zhi)(zhi)(zhi)(zhi)發送(song)到位(wei)(wei)置(zhi)比(bi)較電(dian)路(lu)時，若工(gong)作(zuo)(zuo)臺沒(mei)有(you)移(yi)(yi)(yi)動(dong)(dong)，則沒(mei)有(you)反(fan)饋(kui)(kui)量(liang)，指令(ling)值(zhi)(zhi)(zhi)(zhi)使(shi)得(de)伺服電(dian)動(dong)(dong)機(ji)轉(zhuan)動(dong)(dong)，通(tong)過A將(jiang)(jiang)速度(du)(du)反(fan)饋(kui)(kui)信號送(song)到速度(du)(du)控(kong)(kong)(kong)制(zhi)(zhi)電(dian)路(lu)，通(tong)過C將(jiang)(jiang)工(gong)作(zuo)(zuo)臺實(shi)(shi)(shi)際(ji)位(wei)(wei)移(yi)(yi)(yi)量(liang)反(fan)饋(kui)(kui)回往，在位(wei)(wei)置(zhi)比(bi)較電(dian)路(lu)中(zhong)(zhong)與(yu)位(wei)(wei)移(yi)(yi)(yi)指令(ling)值(zhi)(zhi)(zhi)(zhi)相比(bi)較，用比(bi)較后得(de)到的(de)(de)(de)(de)差(cha)值(zhi)(zhi)(zhi)(zhi)進(jin)(jin)行(xing)(xing)位(wei)(wei)置(zhi)控(kong)(kong)(kong)制(zhi)(zhi)，直至(zhi)差(cha)值(zhi)(zhi)(zhi)(zhi)為(wei)(wei)零(ling)時為(wei)(wei)止。這類控(kong)(kong)(kong)制(zhi)(zhi)的(de)(de)(de)(de)數控(kong)(kong)(kong)機(ji)床(chuang)(chuang)，因把機(ji)床(chuang)(chuang)工(gong)作(zuo)(zuo)臺納進(jin)(jin)了控(kong)(kong)(kong)制(zhi)(zhi)環節，故稱為(wei)(wei)閉(bi)(bi)環控(kong)(kong)(kong)制(zhi)(zhi)數控(kong)(kong)(kong)機(ji)床(chuang)(chuang)。 
        閉(bi)環(huan)控制數控機床的定位精(jing)度(du)高(gao)，但調試和維(wei)修都較困難，系統復雜，本錢高(gao)。 
3． 半閉(bi)環(huan)控制數(shu)控機床 
       半閉(bi)(bi)環(huan)控(kong)(kong)(kong)(kong)制(zhi)數(shu)控(kong)(kong)(kong)(kong)機(ji)床(chuang)是在(zai)伺(si)服電(dian)動(dong)機(ji)的(de)(de)(de)(de)軸或數(shu)控(kong)(kong)(kong)(kong)機(ji)床(chuang)的(de)(de)(de)(de)傳(chuan)動(dong)絲杠上裝有角位(wei)移電(dian)流檢(jian)測(ce)裝置（如光電(dian)編碼器等），通(tong)過(guo)檢(jian)測(ce)絲杠的(de)(de)(de)(de)轉(zhuan)角間接(jie)地(di)檢(jian)測(ce)移動(dong)部(bu)件的(de)(de)(de)(de)實際位(wei)移，然后反饋到數(shu)控(kong)(kong)(kong)(kong)裝置中往，并對誤差進(jin)行修正。通(tong)過(guo)測(ce)速元件A和光電(dian)編碼盤B可間接(jie)檢(jian)測(ce)出(chu)伺(si)服電(dian)動(dong)機(ji)的(de)(de)(de)(de)轉(zhuan)速，從而(er)推(tui)算出(chu)工(gong)作臺(tai)(tai)的(de)(de)(de)(de)實際位(wei)移量，將此值與(yu)指令值進(jin)行比較(jiao)，用差值來實現(xian)控(kong)(kong)(kong)(kong)制(zhi)。由于工(gong)作臺(tai)(tai)沒有包括在(zai)控(kong)(kong)(kong)(kong)制(zhi)回路中，因(yin)而(er)稱(cheng)為半閉(bi)(bi)環(huan)控(kong)(kong)(kong)(kong)制(zhi)數(shu)控(kong)(kong)(kong)(kong)機(ji)床(chuang)。 
       半閉環控制(zhi)數控系統的調試(shi)比(bi)較方便，并且(qie)具有很好的穩定性。目(mu)前大(da)多將角(jiao)度檢(jian)測裝置和伺服電動機設(she)計成(cheng)一體(ti)，這樣，使結構更(geng)加緊(jin)湊。 
4．混合控制(zhi)數控機床 
       將(jiang)以上三類數(shu)(shu)控(kong)(kong)機(ji)(ji)床(chuang)的(de)特點結合起來，就形成了混(hun)合控(kong)(kong)制(zhi)數(shu)(shu)控(kong)(kong)機(ji)(ji)床(chuang)。混(hun)合控(kong)(kong)制(zhi)數(shu)(shu)控(kong)(kong)機(ji)(ji)床(chuang)特別(bie)適(shi)用于(yu)大型(xing)或(huo)重型(xing)數(shu)(shu)控(kong)(kong)機(ji)(ji)床(chuang)，由于(yu)大型(xing)或(huo)重型(xing)數(shu)(shu)控(kong)(kong)機(ji)(ji)床(chuang)需要較高(gao)的(de)進給速(su)度與相當高(gao)的(de)精(jing)度，其傳動鏈慣量與力矩大，假如(ru)只采用全閉環(huan)控(kong)(kong)制(zhi)，機(ji)(ji)床(chuang)傳動鏈和工作臺全部置于(yu)控(kong)(kong)制(zhi)閉環(huan)中(zhong)，閉環(huan)調試比較復雜。混(hun)合控(kong)(kong)制(zhi)系統又分為兩種形式： 
   （1）開環補償型。它(ta)的基(ji)本控制選用步進電(dian)動機的開環伺服機構，另外附(fu)加一(yi)個(ge)校正(zheng)電(dian)路。用裝在工(gong)作(zuo)臺的直線位(wei)移丈量(liang)元件的反饋信號校正(zheng)機械系統的誤差。 
   （2）半閉(bi)環補償型(xing)。它是用(yong)半閉(bi)環控(kong)(kong)制方式取得高精(jing)度(du)控(kong)(kong)制，再用(yong)裝在工作臺(tai)上的(de)直(zhi)(zhi)線(xian)位(wei)移(yi)丈量元(yuan)件(jian)實現全閉(bi)環修正，以獲得高速度(du)與高精(jing)度(du)的(de)同一。其中(zhong)A是速度(du)丈量元(yuan)件(jian)（如(ru)測速發電機），B是角度(du)丈量元(yuan)件(jian)，C是直(zhi)(zhi)線(xian)位(wei)移(yi)丈量元(yuan)件(jian)