什么是裹背(bei)條，裹背(bei)條是通過皮殼機(ji)(ji)等機(ji)(ji)械用于精裝(zhuang)書(shu)(shu)本(ben)的書(shu)(shu)脊部分，使書(shu)(shu)貼連接得更加牢固。書(shu)(shu)脊制作弧長的計算，本(ben)器規格依(yi)書(shu)(shu)芯幅面大小進行調(diao)定(ding)，以能將(jiang)書(shu)(shu)芯平穩地(di)送(song)進夾書(shu)(shu)裝(zhuang)置(zhi)內為(wei)標準(zhun)。入本(ben)后(hou)的書(shu)(shu)冊(ce)不斜歪，四角垂(chui)直地(di)頂齊在夾書(shu)(shu)裝(zhuang)置(zhi)的靠板(ban)、側規內。裁(cai)切尺寸正確一致，其質量要(yao)求與規格誤差與一般切書(shu)(shu)相同。

夾書簽絲帶裝置安放(fang)在切書機(ji)與扒圓起脊機(ji)之間(jian)。即將切完(wan)的書芯(xin)(xin)，用分本器(qi)從(cong)中間(jian)分開，再由輸放(fang)絲帶器(qi)將絲帶夾入中心紙書芯(xin)(xin)的中間(jian)靠訂縫一邊(bian)。絲帶夾在書芯(xin)(xin)內兩端各(ge)留(liu)出粘邊(bian)和使(shi)用的余地，再經(jing)切刀（剪刀式）將其剪斷。

剪斷后的(de)絲帶(dai)，裹背(bei)(bei)(bei)條芯(xin)(xin)(xin)部(bu)分被下(xia)面(mian)膠(jiao)輥著膠(jiao)、壓實(shi)完成夾(jia)書(shu)(shu)(shu)(shu)(shu)簽絲帶(dai)過程。書(shu)(shu)(shu)(shu)(shu)簽絲帶(dai)的(de)長(chang)度與一般手工加(jia)工長(chang)度基本相(xiang)同，可依(yi)書(shu)(shu)(shu)(shu)(shu)冊幅面(mian)長(chang)度調定。扒圓(yuan)(yuan)(yuan)起(qi)脊(ji)操作及(ji)要求。書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)經裁切、夾(jia)粘(zhan)絲帶(dai)（或(huo)(huo)不(bu)(bu)夾(jia)粘(zhan)絲帶(dai)）后，繼續傳送(song)（或(huo)(huo)翻(fan)(fan)轉變位）并做90°翻(fan)(fan)轉，使平(ping)放(fang)書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)變為(wei)(wei)后背(bei)(bei)(bei)朝上（或(huo)(huo)朝下(xia)）而進入扒圓(yuan)(yuan)(yuan)起(qi)脊(ji)機(ji)。扒圓(yuan)(yuan)(yuan)起(qi)脊(ji)機(ji)的(de)加(jia)工，其操作分為(wei)(wei)兩步，但機(ji)器的(de)結構是(shi)連在一起(qi)的(de)，均是(shi)先扒圓(yuan)(yuan)(yuan)后起(qi)脊(ji)。扒圓(yuan)(yuan)(yuan)。扒圓(yuan)(yuan)(yuan)起(qi)脊(ji)機(ji)在扒圓(yuan)(yuan)(yuan)時，由一組(zu)（或(huo)(huo)一對(dui)）圓(yuan)(yuan)(yuan)輥，將書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)壓緊后作相(xiang)對(dui)旋轉動作），使書(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)扒成適當規格圓(yuan)(yuan)(yuan)勢，加(jia)工成圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)。書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)書(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)的(de)形狀分為(wei)(wei)圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)有脊(ji)、圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)無(wu)脊(ji)和(he)方背(bei)(bei)(bei)（或(huo)(huo)稱(cheng)平(ping)背(bei)(bei)(bei)）三種。平(ping)裝裹背(bei)(bei)(bei)條書(shu)(shu)(shu)(shu)(shu)刊(kan)的(de)書(shu)(shu)(shu)(shu)(shu)脊(ji)不(bu)(bu)高出書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)平(ping)面(mian)，而精裝書(shu)(shu)(shu)(shu)(shu)刊(kan)的(de)書(shu)(shu)(shu)(shu)(shu)脊(ji)一般要高出書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)的(de)平(ping)面(mian)。書(shu)(shu)(shu)(shu)(shu)脊(ji)分為(wei)(wei)真脊(ji)和(he)假脊(ji)。

真脊是(shi)利(li)用(yong)書(shu)(shu)背(bei)上下(xia)兩邊(bian)變形(xing)的弧度高出書(shu)(shu)芯平面(mian)；假脊則是(shi)利(li)用(yong)紙(zhi)板鑲在書(shu)(shu)背(bei)后(hou)形(xing)成的書(shu)(shu)脊，書(shu)(shu)脊的脊高等于封面(mian)紙(zhi)板的厚度。方(fang)背(bei)書(shu)(shu)芯。是(shi)指書(shu)(shu)芯的書(shu)(shu)背(bei)平直方(fang)正。書(shu)(shu)背(bei)不(bu)突(tu)出，與平裝書(shu)(shu)刊的書(shu)(shu)背(bei)基本(ben)相(xiang)似(si)。

背與書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)上(shang)(shang)下環襯互成(cheng)直角(jiao)，由于(yu)精(jing)裝(zhuang)(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)是用(yong)鎖線訂訂連(lian)，每一(yi)(yi)(yi)個書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖的(de)(de)訂口折縫里面都用(yong)線串過，因此，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)背脊(ji)比書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖其它部分要厚(hou)(hou)一(yi)(yi)(yi)些，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍的(de)(de)帖數越多，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊(ji)背與書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)其它部分厚(hou)(hou)度(du)(du)的(de)(de)差別也越大。所以方背書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)的(de)(de)形(xing)(xing)式一(yi)(yi)(yi)般只用(yong)于(yu)厚(hou)(hou)度(du)(du)約(yue)為20mm的(de)(de)精(jing)裝(zhuang)(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍。圓(yuan)背有(you)(you)脊(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)。圓(yuan)背有(you)(you)脊(ji)又(you)稱圓(yuan)背真脊(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)。書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)背部呈(cheng)圓(yuan)弧形(xing)(xing)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊(ji)高起有(you)(you)脊(ji)壟(long)，堅硬挺實，這種(zhong)(zhong)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背的(de)(de)形(xing)(xing)式適合于(yu)裝(zhuang)(zhuang)訂較厚(hou)(hou)的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍，裝(zhuang)(zhuang)上(shang)(shang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)后有(you)(you)明顯的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)槽，翻閱方便。目前我國的(de)(de)精(jing)裝(zhuang)(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍多采(cai)用(yong)這種(zhong)(zhong)圓(yuan)背有(you)(you)脊(ji)的(de)(de)加工形(xing)(xing)式。圓(yuan)背無脊(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)。圓(yuan)背無脊(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)又(you)稱圓(yuan)背假(jia)脊(ji)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)背部呈(cheng)圓(yuan)弧形(xing)(xing)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背與書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)的(de)(de)厚(hou)(hou)度(du)(du)相同，堅實挺括，但沒(mei)有(you)(you)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)裹背條脊(ji)。這種(zhong)(zhong)形(xing)(xing)式的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)，一(yi)(yi)(yi)般常與軟質書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)或(huo)塑料(liao)壓制而(er)成(cheng)的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)相配(pei)套。中心紙有(you)(you)些機器(qi)還沒(mei)有(you)(you)沖(chong)(chong)圓(yuan)裝(zhuang)(zhuang)置(zhi)，即將方背書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)先(xian)進行(xing)沖(chong)(chong)圓(yuan)加工，作初步定型。先(xian)根(gen)據(ju)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)厚(hou)(hou)度(du)(du)和中心紙幅面大小調定好夾(jia)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)器(qi)及扒圓(yuan)輥（或(huo)沖(chong)(chong)圓(yuan)裝(zhuang)(zhuang)置(zhi)）的(de)(de)規(gui)矩，再使書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)進入夾(jia)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)器(qi)內并送到扒圓(yuan)輥之間，將書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背扒擠成(cheng)一(yi)(yi)(yi)定圓(yuan)勢(shi)。