CNC(數控(kong)(kong)機(ji)床(chuang))是(shi)計算機(ji)數字控(kong)(kong)制機(ji)床(chuang)(Computer numerical control)的(de)簡稱(cheng)﹐是(shi)一(yi)種由程序(xu)控(kong)(kong)制的(de)自動(dong)化機(ji)床(chuang)。該控(kong)(kong)制系統能夠邏輯(ji)地(di)處理真(zhen)有控(kong)(kong)制編碼(ma)或其(qi)他符號指令規定的(de)程序(xu)﹐通過計算機(ji)將其(qi)譯碼(ma)﹐從而使機(ji)床(chuang)執行(xing)規定好了的(de)動(dong)作﹐通過刀具(ju)切(qie)削(xue)將毛(mao)坯料(liao)加工成半(ban)成品或成品零件(jian)。
CNC數控的特點:(與普通機床相比)
1、加工精度(du)高﹐具有穩定的(de)加工質(zhi)量﹔
2、可進行(xing)多坐(zuo)標的聯動﹐能加工形狀復雜的零件﹔
3、加工零件改變時(shi)(shi)﹐一般只需要更(geng)改數控程(cheng)序﹐可(ke)節省(sheng)生產準備時(shi)(shi)間(jian)﹔
4、機(ji)床本(ben)身的精度高·剛(gang)性大﹐可選擇有利的加工用量(liang)﹐生產效率高(一般為普通(tong)機(ji)床的3~5倍(bei))﹔
5、機床自(zi)動(dong)化程度高﹐可(ke)以減輕勞動(dong)強度﹔
6、批量化生產(chan)﹐產(chan)品質量容易控制(zhi)﹔
7、對(dui)操作人(ren)員的素質要(yao)求較(jiao)低﹐對(dui)維護(hu)人(ren)員的技術要(yao)求較(jiao)高(gao)
CNC數控設備(bei)選用:
一、根據被(bei)加工(gong)產品選用
每一種加工(gong)機床(chuang)都有(you)其(qi)最(zui)佳加工(gong)的(de)典(dian)型(xing)零件,因此應根據加工(gong)零件的(de)不(bu)同(tong)選擇(ze)不(bu)同(tong)的(de)數控機床(chuang)。
二、根據機床的主(zhu)參數(shu)選用
1、在(zai)機床(chuang)所有參數(shu)中,坐(zuo)(zuo)標(biao)軸的(de)(de)行(xing)程是(shi)主要(yao)的(de)(de)參數(shu)。最基本(ben)的(de)(de)是(shi)X、Y、Z三個(ge)坐(zuo)(zuo)標(biao)軸,這三個(ge)坐(zuo)(zuo)標(biao)軸的(de)(de)行(xing)程反映機床(chuang)的(de)(de)加(jia)工能力
2、刀庫容量(liang)也是機床(chuang)的主要(yao)參數。選擇機床(chuang)時,要(yao)根(gen)據被加工零件的工藝分(fen)析結果(guo)確定(ding)所需刀具(ju)數量(liang)。(立(li)加一般24把左右;臥加可有30~125左右;標機選40左右較合適(shi))。
三、根據機(ji)床精度選用(yong)
要(yao)根據被加(jia)工零件關鍵(jian)部位(wei)(wei)加(jia)工精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)要(yao)求來確定(ding)(ding)(ding)機(ji)床(chuang)的精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)等級。直(zhi)線(xian)定(ding)(ding)(ding)位(wei)(wei)精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)、重(zhong)復(fu)定(ding)(ding)(ding)位(wei)(wei)精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)、銑圓精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)是評價數控機(ji)床(chuang)精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)的三(san)個指標。通常情況下,普通數控銑床(chuang)、加(jia)工中(zhong)心的直(zhi)線(xian)定(ding)(ding)(ding)位(wei)(wei)精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)為±0.01mm全程,重(zhong)復(fu)定(ding)(ding)(ding)位(wei)(wei)精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)為±0.006mm,銑床(chuang)圓精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)為0.03~0.04mm。精(jing)(jing)(jing)(jing)密型(xing)加(jia)工中(zhong)心直(zhi)線(xian)定(ding)(ding)(ding)位(wei)(wei)精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)為±0.005mm,重(zhong)復(fu)定(ding)(ding)(ding)位(wei)(wei)精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)為±0.002mm,銑圓精(jing)(jing)(jing)(jing)度(du)(du)(du)(du)為0.02mm。