什(shen)么是裹(guo)背(bei)條，裹(guo)背(bei)條是通(tong)過皮殼(ke)機(ji)等機(ji)械用于精裝(zhuang)書本(ben)的書脊部分，使書貼(tie)連(lian)接得更加(jia)牢固。書脊制作(zuo)弧長的計算，本(ben)器規格依書芯幅面(mian)大小進行調定，以能將書芯平穩地(di)送進夾(jia)(jia)書裝(zhuang)置內(nei)為(wei)標準。入(ru)本(ben)后的書冊不斜歪，四角垂直地(di)頂齊在夾(jia)(jia)書裝(zhuang)置的靠(kao)板、側規內(nei)。裁切(qie)尺(chi)寸正確一致，其質量要求與規格誤差與一般切(qie)書相同(tong)。

夾(jia)書簽絲帶(dai)裝置(zhi)安放在切書機與扒圓(yuan)起脊機之間。即將(jiang)(jiang)切完的(de)(de)書芯，用分本器(qi)從中(zhong)間分開，再由(you)輸放絲帶(dai)器(qi)將(jiang)(jiang)絲帶(dai)夾(jia)入中(zhong)心(xin)紙書芯的(de)(de)中(zhong)間靠訂縫一邊。絲帶(dai)夾(jia)在書芯內兩端各(ge)留出粘邊和(he)使(shi)用的(de)(de)余地，再經切刀（剪刀式）將(jiang)(jiang)其剪斷。

剪斷后(hou)(hou)(hou)的(de)(de)絲(si)帶(dai)(dai)，裹(guo)背(bei)(bei)條芯部分(fen)被下(xia)面膠輥(gun)(gun)著膠、壓實完(wan)成(cheng)夾(jia)(jia)書(shu)(shu)(shu)(shu)簽絲(si)帶(dai)(dai)過程。書(shu)(shu)(shu)(shu)簽絲(si)帶(dai)(dai)的(de)(de)長度與一(yi)般手工(gong)(gong)加(jia)工(gong)(gong)長度基本相(xiang)同(tong)，可依書(shu)(shu)(shu)(shu)冊(ce)幅(fu)面長度調定。扒(ba)圓(yuan)(yuan)(yuan)起(qi)(qi)脊(ji)操作(zuo)及(ji)要求(qiu)。書(shu)(shu)(shu)(shu)芯經裁(cai)切、夾(jia)(jia)粘(zhan)絲(si)帶(dai)(dai)（或(huo)不(bu)夾(jia)(jia)粘(zhan)絲(si)帶(dai)(dai)）后(hou)(hou)(hou)，繼續傳送（或(huo)翻轉變位）并做90°翻轉，使平(ping)(ping)放書(shu)(shu)(shu)(shu)芯變為后(hou)(hou)(hou)背(bei)(bei)朝上（或(huo)朝下(xia)）而進入扒(ba)圓(yuan)(yuan)(yuan)起(qi)(qi)脊(ji)機。扒(ba)圓(yuan)(yuan)(yuan)起(qi)(qi)脊(ji)機的(de)(de)加(jia)工(gong)(gong)，其操作(zuo)分(fen)為兩步，但機器的(de)(de)結構是連在(zai)一(yi)起(qi)(qi)的(de)(de)，均是先扒(ba)圓(yuan)(yuan)(yuan)后(hou)(hou)(hou)起(qi)(qi)脊(ji)。扒(ba)圓(yuan)(yuan)(yuan)。扒(ba)圓(yuan)(yuan)(yuan)起(qi)(qi)脊(ji)機在(zai)扒(ba)圓(yuan)(yuan)(yuan)時，由一(yi)組(zu)（或(huo)一(yi)對(dui)）圓(yuan)(yuan)(yuan)輥(gun)(gun)，將書(shu)(shu)(shu)(shu)芯壓緊后(hou)(hou)(hou)作(zuo)相(xiang)對(dui)旋轉動作(zuo)），使書(shu)(shu)(shu)(shu)背(bei)(bei)扒(ba)成(cheng)適當規格圓(yuan)(yuan)(yuan)勢，加(jia)工(gong)(gong)成(cheng)圓(yuan)(yuan)(yuan)背(bei)(bei)書(shu)(shu)(shu)(shu)芯。書(shu)(shu)(shu)(shu)芯書(shu)(shu)(shu)(shu)背(bei)(bei)的(de)(de)形狀(zhuang)分(fen)為圓(yuan)(yuan)(yuan)背(bei)(bei)有脊(ji)、圓(yuan)(yuan)(yuan)背(bei)(bei)無脊(ji)和方背(bei)(bei)（或(huo)稱平(ping)(ping)背(bei)(bei)）三種。平(ping)(ping)裝(zhuang)裹(guo)背(bei)(bei)條書(shu)(shu)(shu)(shu)刊的(de)(de)書(shu)(shu)(shu)(shu)脊(ji)不(bu)高出書(shu)(shu)(shu)(shu)芯平(ping)(ping)面，而精裝(zhuang)書(shu)(shu)(shu)(shu)刊的(de)(de)書(shu)(shu)(shu)(shu)脊(ji)一(yi)般要高出書(shu)(shu)(shu)(shu)芯的(de)(de)平(ping)(ping)面。書(shu)(shu)(shu)(shu)脊(ji)分(fen)為真脊(ji)和假脊(ji)。

真脊(ji)(ji)是利用(yong)書(shu)(shu)(shu)(shu)背(bei)上下(xia)兩(liang)邊變形(xing)的弧度高(gao)出(chu)書(shu)(shu)(shu)(shu)芯平(ping)面；假(jia)脊(ji)(ji)則是利用(yong)紙板鑲在書(shu)(shu)(shu)(shu)背(bei)后形(xing)成的書(shu)(shu)(shu)(shu)脊(ji)(ji)，書(shu)(shu)(shu)(shu)脊(ji)(ji)的脊(ji)(ji)高(gao)等于(yu)封(feng)面紙板的厚度。方背(bei)書(shu)(shu)(shu)(shu)芯。是指書(shu)(shu)(shu)(shu)芯的書(shu)(shu)(shu)(shu)背(bei)平(ping)直方正。書(shu)(shu)(shu)(shu)背(bei)不突出(chu)，與平(ping)裝書(shu)(shu)(shu)(shu)刊的書(shu)(shu)(shu)(shu)背(bei)基(ji)本相似。

背(bei)(bei)(bei)(bei)(bei)與(yu)(yu)(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)上(shang)下環襯(chen)互成(cheng)(cheng)直角，由(you)于精(jing)裝(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)是(shi)用(yong)鎖線(xian)訂(ding)訂(ding)連，每一(yi)個書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖(tie)的(de)(de)(de)訂(ding)口折縫里面(mian)都用(yong)線(xian)串過，因此，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)背(bei)(bei)(bei)(bei)(bei)脊比書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖(tie)其它部分要厚(hou)(hou)(hou)一(yi)些(xie)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍的(de)(de)(de)帖(tie)數(shu)越多，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊背(bei)(bei)(bei)(bei)(bei)與(yu)(yu)(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)其它部分厚(hou)(hou)(hou)度(du)的(de)(de)(de)差別也越大(da)。所(suo)以方背(bei)(bei)(bei)(bei)(bei)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)的(de)(de)(de)形(xing)式一(yi)般只(zhi)用(yong)于厚(hou)(hou)(hou)度(du)約為20mm的(de)(de)(de)精(jing)裝(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍。圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)有(you)(you)(you)(you)脊書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)。圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)有(you)(you)(you)(you)脊又(you)稱(cheng)圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)真脊書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)。書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)背(bei)(bei)(bei)(bei)(bei)部呈(cheng)圓(yuan)(yuan)(yuan)(yuan)(yuan)弧(hu)形(xing)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊高起有(you)(you)(you)(you)脊壟，堅(jian)硬(ying)挺實(shi)，這(zhe)種(zhong)(zhong)(zhong)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)(bei)(bei)的(de)(de)(de)形(xing)式適合于裝(zhuang)訂(ding)較厚(hou)(hou)(hou)的(de)(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍，裝(zhuang)上(shang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)后有(you)(you)(you)(you)明顯的(de)(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)槽，翻(fan)閱方便(bian)。目前我國的(de)(de)(de)精(jing)裝(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍多采用(yong)這(zhe)種(zhong)(zhong)(zhong)圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)有(you)(you)(you)(you)脊的(de)(de)(de)加(jia)工形(xing)式。圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)無脊書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)。圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)無脊書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)又(you)稱(cheng)圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)假脊，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)背(bei)(bei)(bei)(bei)(bei)部呈(cheng)圓(yuan)(yuan)(yuan)(yuan)(yuan)弧(hu)形(xing)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)(bei)(bei)與(yu)(yu)(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)的(de)(de)(de)厚(hou)(hou)(hou)度(du)相同(tong)，堅(jian)實(shi)挺括，但沒(mei)有(you)(you)(you)(you)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)裹背(bei)(bei)(bei)(bei)(bei)條脊。這(zhe)種(zhong)(zhong)(zhong)形(xing)式的(de)(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)，一(yi)般常與(yu)(yu)(yu)軟質(zhi)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)或(huo)塑(su)料壓制而成(cheng)(cheng)的(de)(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)相配套。中心(xin)紙(zhi)有(you)(you)(you)(you)些(xie)機器還沒(mei)有(you)(you)(you)(you)沖(chong)圓(yuan)(yuan)(yuan)(yuan)(yuan)裝(zhuang)置(zhi)，即將方背(bei)(bei)(bei)(bei)(bei)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)先進行沖(chong)圓(yuan)(yuan)(yuan)(yuan)(yuan)加(jia)工，作初步定(ding)型。先根據(ju)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)厚(hou)(hou)(hou)度(du)和中心(xin)紙(zhi)幅面(mian)大(da)小(xiao)調定(ding)好夾書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)器及扒圓(yuan)(yuan)(yuan)(yuan)(yuan)輥（或(huo)沖(chong)圓(yuan)(yuan)(yuan)(yuan)(yuan)裝(zhuang)置(zhi)）的(de)(de)(de)規矩(ju)，再(zai)使書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)(xin)進入夾書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)器內并送(song)到扒圓(yuan)(yuan)(yuan)(yuan)(yuan)輥之間(jian)，將書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)(bei)(bei)扒擠成(cheng)(cheng)一(yi)定(ding)圓(yuan)(yuan)(yuan)(yuan)(yuan)勢(shi)。