凹版印刷機張力控制系統的組成特性
系統由雙(shuang)工(gong)位(wei)放(fang)卷(juan)(juan)、放(fang)卷(juan)(juan)牽引、收卷(juan)(juan)牽引、雙(shuang)工(gong)位(wei)收卷(juan)(juan)張(zhang)力控(kong)(kong)(kong)制(zhi)(zhi)及主(zhu)電機控(kong)(kong)(kong)制(zhi)(zhi)等(deng)五(wu)部分組成。下面(mian)針對這五(wu)部分的各自特點分別(bie)進行(xing)闡述：放(fang)卷(juan)(juan)張(zhang)力控(kong)(kong)(kong)制(zhi)(zhi)包含張(zhang)力檢(jian)測單(dan)(dan)元、張(zhang)力運(yun)算單(dan)(dan)元、伺服執行(xing)機構、自動卷(juan)(juan)徑檢(jian)測單(dan)(dan)元、預驅(qu)動控(kong)(kong)(kong)制(zhi)(zhi)及自動裁切控(kong)(kong)(kong)制(zhi)(zhi)等(deng)。
張力(li)(li)(li)控(kong)制(zhi)(zhi)系統(tong)中(zhong)所用的(de)(de)張力(li)(li)(li)檢(jian)測(ce)(ce)單元為(wei)氣(qi)壓浮動(dong)輥(gun)式張力(li)(li)(li)檢(jian)測(ce)(ce)裝置，通過(guo)對連接(jie)在檢(jian)測(ce)(ce)輥(gun)浮動(dong)擺臂上的(de)(de)氣(qi)缸氣(qi)壓的(de)(de)調(diao)(diao)節來(lai)檢(jian)測(ce)(ce)料(liao)膜張力(li)(li)(li)。當氣(qi)缸氣(qi)壓設(she)定(ding)后，擺臂上的(de)(de)氣(qi)缸推力(li)(li)(li)即(ji)為(wei)定(ding)值(zhi)(zhi)，該控(kong)制(zhi)(zhi)模式的(de)(de)原(yuan)理(li)是通過(guo)材料(liao)線(xian)(xian)速度與(yu)實際卷徑計算(suan)一個匹配(pei)頻率(lv)設(she)定(ding)值(zhi)(zhi)f1，再通過(guo)張力(li)(li)(li)（位置）反(fan)饋信號進(jin)行PID運算(suan)產生一個頻率(lv)調(diao)(diao)整(zheng)值(zhi)(zhi)f2，最終(zhong)頻率(lv)輸出為(wei)f＝f1＋f2。f1可以基本(ben)使收(shou)（放(fang)）卷輥(gun)的(de)(de)線(xian)(xian)速度與(yu)材料(liao)線(xian)(xian)速度基本(ben)匹配(pei)，然后f2部(bu)分只需(xu)(xu)稍(shao)微調(diao)(diao)整(zheng)即(ji)可滿足(zu)控(kong)制(zhi)(zhi)需(xu)(xu)求，很好(hao)地(di)解決了閉環(huan)控(kong)制(zhi)(zhi)中(zhong)響(xiang)應(ying)快速性和控(kong)制(zhi)(zhi)穩定(ding)性地(di)矛盾。處于平(ping)衡態的(de)(de)該系統(tong)，當發生較強干擾時，如系統(tong)瞬(shun)間(jian)來(lai)不及(ji)反(fan)應(ying)，則料(liao)膜上的(de)(de)張力(li)(li)(li)波(bo)動(dong)可暫時由浮動(dong)輥(gun)吸收(shou)。因此浮動(dong)輥(gun)檢(jian)測(ce)(ce)是一種較為(wei)優越的(de)(de)檢(jian)測(ce)(ce)方式。