什么(me)是裹(guo)背條，裹(guo)背條是通(tong)過皮殼機等機械用(yong)于精裝書(shu)(shu)本的(de)書(shu)(shu)脊(ji)部分，使書(shu)(shu)貼連接(jie)得(de)更(geng)加牢固(gu)。書(shu)(shu)脊(ji)制作弧長(chang)的(de)計算，本器規(gui)格依(yi)書(shu)(shu)芯幅面大小進行調定，以能(neng)將書(shu)(shu)芯平(ping)穩地送進夾書(shu)(shu)裝置內為(wei)標準。入(ru)本后的(de)書(shu)(shu)冊不斜歪，四(si)角垂直地頂齊在夾書(shu)(shu)裝置的(de)靠板、側規(gui)內。裁切尺寸(cun)正確一致，其質量要(yao)求與規(gui)格誤(wu)差與一般切書(shu)(shu)相同。

夾(jia)書(shu)簽絲(si)(si)帶裝置(zhi)安(an)放在(zai)切書(shu)機與扒圓起脊機之間(jian)。即將(jiang)切完(wan)的書(shu)芯，用(yong)分本(ben)器從中(zhong)間(jian)分開(kai)，再由輸(shu)放絲(si)(si)帶器將(jiang)絲(si)(si)帶夾(jia)入中(zhong)心紙書(shu)芯的中(zhong)間(jian)靠訂(ding)縫一邊(bian)。絲(si)(si)帶夾(jia)在(zai)書(shu)芯內兩端各留出粘邊(bian)和使用(yong)的余地，再經切刀（剪(jian)刀式(shi)）將(jiang)其剪(jian)斷(duan)。

剪斷(duan)后的(de)(de)(de)絲(si)帶，裹背(bei)(bei)(bei)(bei)條芯部(bu)分(fen)被下面(mian)膠(jiao)輥著膠(jiao)、壓實(shi)完成(cheng)(cheng)夾書(shu)(shu)簽(qian)絲(si)帶過程。書(shu)(shu)簽(qian)絲(si)帶的(de)(de)(de)長(chang)度(du)(du)(du)與一(yi)(yi)般手(shou)工(gong)加工(gong)長(chang)度(du)(du)(du)基本相同，可(ke)依書(shu)(shu)冊幅面(mian)長(chang)度(du)(du)(du)調(diao)定(ding)。扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)(yuan)起脊操作(zuo)及要求。書(shu)(shu)芯經(jing)裁切(qie)、夾粘(zhan)絲(si)帶（或(huo)不夾粘(zhan)絲(si)帶）后，繼(ji)續傳(chuan)送（或(huo)翻(fan)轉(zhuan)變位）并做90°翻(fan)轉(zhuan)，使平(ping)放書(shu)(shu)芯變為后背(bei)(bei)(bei)(bei)朝上（或(huo)朝下）而進入扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)(yuan)起脊機(ji)(ji)。扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)(yuan)起脊機(ji)(ji)的(de)(de)(de)加工(gong)，其操作(zuo)分(fen)為兩(liang)步，但機(ji)(ji)器的(de)(de)(de)結構是連在(zai)(zai)一(yi)(yi)起的(de)(de)(de)，均是先扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)(yuan)后起脊。扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)(yuan)。扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)(yuan)起脊機(ji)(ji)在(zai)(zai)扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)(yuan)時(shi)，由(you)一(yi)(yi)組(zu)（或(huo)一(yi)(yi)對）圓(yuan)(yuan)(yuan)(yuan)(yuan)輥，將書(shu)(shu)芯壓緊(jin)后作(zuo)相對旋轉(zhuan)動作(zuo)），使書(shu)(shu)背(bei)(bei)(bei)(bei)扒(ba)(ba)成(cheng)(cheng)適當規(gui)格圓(yuan)(yuan)(yuan)(yuan)(yuan)勢，加工(gong)成(cheng)(cheng)圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)書(shu)(shu)芯。書(shu)(shu)芯書(shu)(shu)背(bei)(bei)(bei)(bei)的(de)(de)(de)形狀(zhuang)分(fen)為圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)有脊、圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)無脊和方背(bei)(bei)(bei)(bei)（或(huo)稱平(ping)背(bei)(bei)(bei)(bei)）三種。平(ping)裝(zhuang)裹背(bei)(bei)(bei)(bei)條書(shu)(shu)刊的(de)(de)(de)書(shu)(shu)脊不高出書(shu)(shu)芯平(ping)面(mian)，而精裝(zhuang)書(shu)(shu)刊的(de)(de)(de)書(shu)(shu)脊一(yi)(yi)般要高出書(shu)(shu)芯的(de)(de)(de)平(ping)面(mian)。書(shu)(shu)脊分(fen)為真脊和假脊。

真(zhen)脊(ji)是(shi)利用(yong)書(shu)(shu)背(bei)上下兩邊變(bian)形的(de)弧度高出書(shu)(shu)芯平面；假脊(ji)則(ze)是(shi)利用(yong)紙板鑲在書(shu)(shu)背(bei)后形成的(de)書(shu)(shu)脊(ji)，書(shu)(shu)脊(ji)的(de)脊(ji)高等(deng)于(yu)封面紙板的(de)厚度。方背(bei)書(shu)(shu)芯。是(shi)指書(shu)(shu)芯的(de)書(shu)(shu)背(bei)平直方正。書(shu)(shu)背(bei)不突出，與平裝書(shu)(shu)刊的(de)書(shu)(shu)背(bei)基本相似。

背(bei)(bei)(bei)與(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)上下環襯互成直角，由(you)于(yu)精(jing)裝(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)是用(yong)鎖(suo)線(xian)訂(ding)訂(ding)連，每(mei)一(yi)個(ge)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖的(de)(de)(de)(de)訂(ding)口(kou)折縫里(li)面(mian)都用(yong)線(xian)串(chuan)過，因此，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)背(bei)(bei)(bei)脊(ji)(ji)(ji)比書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖其它部分(fen)要厚(hou)(hou)一(yi)些，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍的(de)(de)(de)(de)帖數(shu)越多(duo)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊(ji)(ji)(ji)背(bei)(bei)(bei)與(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)其它部分(fen)厚(hou)(hou)度(du)(du)的(de)(de)(de)(de)差別也(ye)越大。所以方(fang)背(bei)(bei)(bei)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)的(de)(de)(de)(de)形式(shi)一(yi)般只用(yong)于(yu)厚(hou)(hou)度(du)(du)約為20mm的(de)(de)(de)(de)精(jing)裝(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍。圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)有(you)(you)脊(ji)(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)。圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)有(you)(you)脊(ji)(ji)(ji)又稱圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)真脊(ji)(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)。書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)背(bei)(bei)(bei)部呈(cheng)圓(yuan)(yuan)(yuan)弧形，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊(ji)(ji)(ji)高起有(you)(you)脊(ji)(ji)(ji)壟，堅硬挺實，這種(zhong)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)的(de)(de)(de)(de)形式(shi)適合于(yu)裝(zhuang)訂(ding)較(jiao)厚(hou)(hou)的(de)(de)(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍，裝(zhuang)上書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)后有(you)(you)明顯的(de)(de)(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)槽，翻(fan)閱方(fang)便。目前(qian)我國的(de)(de)(de)(de)精(jing)裝(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍多(duo)采(cai)用(yong)這種(zhong)圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)有(you)(you)脊(ji)(ji)(ji)的(de)(de)(de)(de)加工(gong)形式(shi)。圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)無(wu)(wu)脊(ji)(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)。圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)無(wu)(wu)脊(ji)(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)又稱圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)假脊(ji)(ji)(ji)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)背(bei)(bei)(bei)部呈(cheng)圓(yuan)(yuan)(yuan)弧形，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)與(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)的(de)(de)(de)(de)厚(hou)(hou)度(du)(du)相同(tong)，堅實挺括(kuo)，但(dan)沒有(you)(you)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)裹(guo)背(bei)(bei)(bei)條脊(ji)(ji)(ji)。這種(zhong)形式(shi)的(de)(de)(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)，一(yi)般常與(yu)軟(ruan)質(zhi)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)或(huo)塑料壓制(zhi)而成的(de)(de)(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)相配套。中(zhong)心(xin)紙有(you)(you)些機器還沒有(you)(you)沖圓(yuan)(yuan)(yuan)裝(zhuang)置，即將(jiang)方(fang)背(bei)(bei)(bei)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)先(xian)進(jin)行沖圓(yuan)(yuan)(yuan)加工(gong)，作初步定型(xing)。先(xian)根據書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)厚(hou)(hou)度(du)(du)和中(zhong)心(xin)紙幅面(mian)大小調定好(hao)夾書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)器及扒圓(yuan)(yuan)(yuan)輥(gun)（或(huo)沖圓(yuan)(yuan)(yuan)裝(zhuang)置）的(de)(de)(de)(de)規矩(ju)，再(zai)使書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)進(jin)入夾書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)器內并送到扒圓(yuan)(yuan)(yuan)輥(gun)之(zhi)間，將(jiang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)扒擠成一(yi)定圓(yuan)(yuan)(yuan)勢。