CNC龍門加工中心傳統機床雖然比立式加工中心便宜,但是(shi)立式加工中心的(de)價值(zhi)體(ti)(ti)現在生產效率上,好的(de)設(she)計工藝決定了立式加工中心比傳統機床有更多(duo)的(de)優勢(shi),下面我(wo)們來(lai)劃分一下具(ju)體(ti)(ti)的(de)優勢(shi).
1、立式(shi)加工(gong)中心(xin)具有(you)(you)更高(gao)(gao)的(de)(de)(de)靜態和動(dong)態風范。立式(shi)加工(gong)中心(xin)的(de)(de)(de)效(xiao)(xiao)率高(gao)(gao)于傳統(tong)機(ji)床,這(zhe)(zhe)就要求(qiu)必(bi)須采(cai)取措(cuo)(cuo)施(shi),大(da)幅度(du)減(jian)少單件(jian)(jian)加工(gong)時間。壓縮時間包(bao)括兩(liang)個(ge)方(fang)面(mian):一方(fang)面(mian),新刀具材料的(de)(de)(de)開發,如切削(xue)速度(du)成倍(bei)增加,大(da)大(da)恢復了(le)官方(fang)切削(xue)時間;另一方(fang)面(mian),采(cai)用自動(dong)換刀系統(tong)對操作進行(xing)改(gai)(gai)造(zao),大(da)大(da)減(jian)少了(le)輔(fu)助(zhu)時間。這(zhe)(zhe)些措(cuo)(cuo)施(shi)大(da)大(da)提高(gao)(gao)了(le)生產(chan)效(xiao)(xiao)率,取得了(le)良(liang)好的(de)(de)(de)經(jing)濟效(xiao)(xiao)益,但在(zai)設(she)計結(jie)(jie)構上也顯著(zhu)增加了(le)機(ji)床和加工(gong)中心(xin)的(de)(de)(de)負(fu)荷,考慮到這(zhe)(zhe)些,因此(ci)其基本大(da)件(jian)(jian)通常采(cai)用封閉箱式(shi)結(jie)(jie)構,合理布置加強板和加強件(jian)(jian)有(you)(you)效(xiao)(xiao)接(jie)觸(chu)恩、靜恩。此(ci)外,調整零部件(jian)(jian)的(de)(de)(de)質量可能會改(gai)(gai)變系統(tong)的(de)(de)(de)固有(you)(you)振(zhen)動(dong)頻率,增加阻尼可以改(gai)(gai)善機(ji)床的(de)(de)(de)阻尼特(te)性,是改(gai)(gai)善機(ji)床動(dong)態行(xing)為的(de)(de)(de)有(you)(you)效(xiao)(xiao)措(cuo)(cuo)施(shi)。
2、立式加工中心具有靜剛度。機床床身、導軌、工作臺、刀架和主軸箱的結構剛度會影響其自身的幾何精度,由于變形存在這些因素,要求數控機床具有較高的靜剛度。切削(xue)過程(cheng)中(zhong)的振動不僅(jin)直接(jie)影響零件的加(jia)工(gong)(gong)精(jing)度和(he)表面質(zhi)量,還(huan)會降低刀具壽命(ming),影響加(jia)工(gong)(gong)中(zhong)心(xin)連續運轉,不能在加(jia)工(gong)(gong)過程(cheng)中(zhong)人為調整(如更換切削(xue)用量或(huo)改變刀具幾何(he)角(jiao)度)來消除(chu)或(huo)減(jian)少振動,因(yin)此,還(huan)必須提(ti)高加(jia)工(gong)(gong)中(zhong)心(xin)的動態剛度。
3、立式加工(gong)(gong)中(zhong)心熱(re)(re)(re)(re)變形(xing)較(jiao)小。加工(gong)(gong)中(zhong)心在(zai)切削(xue)熱(re)(re)(re)(re)、摩(mo)擦熱(re)(re)(re)(re)等內外熱(re)(re)(re)(re)的過程中(zhong),零件會產生不(bu)同程度(du)(du)的熱(re)(re)(re)(re)變形(xing),從而影(ying)響工(gong)(gong)作的精(jing)度(du)(du)。由于加工(gong)(gong)中(zhong)心的主軸(zhou)轉速(su)、進(jin)給速(su)度(du)(du)和切削(xue)量均大于傳統機床,而且(qie)工(gong)(gong)藝自動(dong)化,往(wang)往(wang)是連續加工(gong)(gong),并(bing)通(tong)過液冷、冷購等方法產生的熱(re)(re)(re)(re)量來控制溫升;改進(jin)了機床結構,使零件的熱(re)(re)(re)(re)變形(xing)發(fa)生在(zai)非誤差敏(min)感方向。
4、立(li)式加(jia)(jia)工(gong)(gong)(gong)(gong)中(zhong)心(xin)(xin)運動(dong)(dong)部(bu)(bu)件(jian)摩(mo)擦小(xiao),消除傳(chuan)動(dong)(dong)系(xi)統(tong)間隙。加(jia)(jia)工(gong)(gong)(gong)(gong)中(zhong)心(xin)(xin)工(gong)(gong)(gong)(gong)作(zuo)(zuo)臺的(de)(de)(de)(de)位移以脈沖當量為最小(xiao)單位,在(zai)(zai)刀的(de)(de)(de)(de)情況下(xia)(xia),運動(dong)(dong)的(de)(de)(de)(de)速度。這就要求工(gong)(gong)(gong)(gong)作(zuo)(zuo)臺能(neng)準確(que)響應數控裝(zhuang)置(zhi)發(fa)出的(de)(de)(de)(de)指(zhi)令,它與運動(dong)(dong)部(bu)(bu)件(jian)的(de)(de)(de)(de)摩(mo)擦特性有關,加(jia)(jia)工(gong)(gong)(gong)(gong)中(zhong)心(xin)(xin)采用(yong)滾(gun)動(dong)(dong)導軌,滾(gun)動(dong)(dong)導軌的(de)(de)(de)(de)靜(jing)摩(mo)擦力小(xiao),并在(zai)(zai)潤(run)滑油的(de)(de)(de)(de)作(zuo)(zuo)用(yong)下(xia)(xia),摩(mo)擦力隨速度的(de)(de)(de)(de)增加(jia)(jia)而減小(xiao),有效避(bi)免了(le)低速爬行現象,從(cong)而提高(gao)了(le)加(jia)(jia)工(gong)(gong)(gong)(gong)中(zhong)心(xin)(xin)性和定位精度。在(zai)(zai)進給系(xi)統(tong)中(zhong)使(shi)用(yong)滾(gun)珠絲(si)杠代替滑動(dong)(dong)絲(si)杠是基于相同的(de)(de)(de)(de)原理。此外(wai),采用(yong)脈沖補償裝(zhuang)置(zhi)進行螺距補償、游(you)隙的(de)(de)(de)(de)傳(chuan)動(dong)(dong)系(xi)統(tong),以及一些無(wu)游(you)隙傳(chuan)動(dong)(dong)副(fu)的(de)(de)(de)(de)機床。
5、立式加(jia)工(gong)中心使(shi)用(yong)壽(shou)命高,精(jing)度(du)保持性好。良(liang)好的潤滑系(xi)統(tong)保證了立式加(jia)工(gong)中心的使(shi)用(yong)壽(shou)命,導軌(gui)、進給絲(si)杠和(he)主軸部件均采用(yong)新型耐磨(mo)中心,在長期使(shi)用(yong)過程(cheng)中能保持良(liang)好的精(jing)度(du)。