什么(me)是裹背條，裹背條是通過皮殼機(ji)等機(ji)械用于精裝(zhuang)書(shu)(shu)本(ben)的(de)書(shu)(shu)脊部分，使書(shu)(shu)貼連接得更(geng)加牢(lao)固。書(shu)(shu)脊制作弧長的(de)計算，本(ben)器規(gui)格依書(shu)(shu)芯幅(fu)面大(da)小進行調定，以(yi)能將(jiang)書(shu)(shu)芯平穩地送(song)進夾書(shu)(shu)裝(zhuang)置內(nei)(nei)為標準。入本(ben)后的(de)書(shu)(shu)冊不斜歪，四(si)角垂直地頂(ding)齊(qi)在夾書(shu)(shu)裝(zhuang)置的(de)靠板(ban)、側規(gui)內(nei)(nei)。裁(cai)切尺寸正(zheng)確(que)一致，其質(zhi)量要求(qiu)與(yu)規(gui)格誤差與(yu)一般(ban)切書(shu)(shu)相同(tong)。

夾(jia)(jia)書(shu)簽絲帶裝置安放在切書(shu)機(ji)與(yu)扒圓起脊機(ji)之間(jian)。即將切完的(de)書(shu)芯，用(yong)分(fen)本(ben)器(qi)從中間(jian)分(fen)開(kai)，再由輸放絲帶器(qi)將絲帶夾(jia)(jia)入中心紙(zhi)書(shu)芯的(de)中間(jian)靠(kao)訂(ding)縫一邊。絲帶夾(jia)(jia)在書(shu)芯內(nei)兩端各留(liu)出粘邊和(he)使用(yong)的(de)余地，再經切刀（剪刀式(shi)）將其(qi)剪斷。

剪斷后(hou)的(de)(de)絲帶，裹背(bei)(bei)(bei)條芯(xin)(xin)部分被下面(mian)(mian)膠(jiao)輥著膠(jiao)、壓(ya)實完成(cheng)夾書(shu)(shu)(shu)(shu)(shu)簽(qian)絲帶過程(cheng)。書(shu)(shu)(shu)(shu)(shu)簽(qian)絲帶的(de)(de)長度(du)與(yu)一(yi)般(ban)手工(gong)加工(gong)長度(du)基本相同，可依書(shu)(shu)(shu)(shu)(shu)冊幅(fu)面(mian)(mian)長度(du)調(diao)定。扒(ba)圓(yuan)(yuan)(yuan)起(qi)脊(ji)(ji)操(cao)(cao)作(zuo)及要求。書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)經裁切、夾粘絲帶（或不(bu)夾粘絲帶）后(hou)，繼續傳(chuan)送（或翻轉(zhuan)變(bian)(bian)位(wei)）并做90°翻轉(zhuan)，使平放(fang)書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)變(bian)(bian)為后(hou)背(bei)(bei)(bei)朝(chao)上(shang)（或朝(chao)下）而(er)進入扒(ba)圓(yuan)(yuan)(yuan)起(qi)脊(ji)(ji)機(ji)。扒(ba)圓(yuan)(yuan)(yuan)起(qi)脊(ji)(ji)機(ji)的(de)(de)加工(gong)，其操(cao)(cao)作(zuo)分為兩(liang)步(bu)，但機(ji)器的(de)(de)結(jie)構是連在(zai)一(yi)起(qi)的(de)(de)，均是先扒(ba)圓(yuan)(yuan)(yuan)后(hou)起(qi)脊(ji)(ji)。扒(ba)圓(yuan)(yuan)(yuan)。扒(ba)圓(yuan)(yuan)(yuan)起(qi)脊(ji)(ji)機(ji)在(zai)扒(ba)圓(yuan)(yuan)(yuan)時，由一(yi)組（或一(yi)對）圓(yuan)(yuan)(yuan)輥，將書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)壓(ya)緊后(hou)作(zuo)相對旋轉(zhuan)動作(zuo)），使書(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)扒(ba)成(cheng)適(shi)當規格圓(yuan)(yuan)(yuan)勢，加工(gong)成(cheng)圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)。書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)書(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)的(de)(de)形狀分為圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)有脊(ji)(ji)、圓(yuan)(yuan)(yuan)背(bei)(bei)(bei)無脊(ji)(ji)和方(fang)背(bei)(bei)(bei)（或稱平背(bei)(bei)(bei)）三(san)種(zhong)。平裝(zhuang)裹背(bei)(bei)(bei)條書(shu)(shu)(shu)(shu)(shu)刊的(de)(de)書(shu)(shu)(shu)(shu)(shu)脊(ji)(ji)不(bu)高(gao)(gao)出書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)平面(mian)(mian)，而(er)精裝(zhuang)書(shu)(shu)(shu)(shu)(shu)刊的(de)(de)書(shu)(shu)(shu)(shu)(shu)脊(ji)(ji)一(yi)般(ban)要高(gao)(gao)出書(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)的(de)(de)平面(mian)(mian)。書(shu)(shu)(shu)(shu)(shu)脊(ji)(ji)分為真脊(ji)(ji)和假脊(ji)(ji)。

真(zhen)脊(ji)是利用(yong)書背(bei)(bei)上下(xia)兩邊變形(xing)的(de)弧(hu)度高(gao)出書芯平(ping)(ping)面；假脊(ji)則是利用(yong)紙(zhi)板(ban)(ban)鑲(xiang)在(zai)書背(bei)(bei)后形(xing)成的(de)書脊(ji)，書脊(ji)的(de)脊(ji)高(gao)等于(yu)封面紙(zhi)板(ban)(ban)的(de)厚(hou)度。方背(bei)(bei)書芯。是指書芯的(de)書背(bei)(bei)平(ping)(ping)直(zhi)方正。書背(bei)(bei)不突(tu)出，與平(ping)(ping)裝書刊(kan)的(de)書背(bei)(bei)基本相(xiang)似(si)。

背(bei)與書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)上下環襯互成(cheng)直角，由于(yu)精(jing)裝(zhuang)(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)是用(yong)(yong)鎖線(xian)訂訂連，每一(yi)個書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖(tie)(tie)(tie)的(de)(de)訂口折縫里面都用(yong)(yong)線(xian)串過，因此，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)背(bei)脊(ji)(ji)比書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖(tie)(tie)(tie)其它部分要(yao)厚(hou)(hou)一(yi)些，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍(ji)的(de)(de)帖(tie)(tie)(tie)數越(yue)多(duo)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊(ji)(ji)背(bei)與書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)其它部分厚(hou)(hou)度的(de)(de)差別也越(yue)大。所(suo)以方(fang)背(bei)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)的(de)(de)形式一(yi)般只用(yong)(yong)于(yu)厚(hou)(hou)度約(yue)為20mm的(de)(de)精(jing)裝(zhuang)(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍(ji)。圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)有(you)(you)脊(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)。圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)有(you)(you)脊(ji)(ji)又(you)(you)稱圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)真脊(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)。書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)背(bei)部呈(cheng)圓(yuan)(yuan)(yuan)(yuan)(yuan)弧形，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊(ji)(ji)高起有(you)(you)脊(ji)(ji)壟，堅(jian)硬挺實，這種(zhong)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)的(de)(de)形式適合于(yu)裝(zhuang)(zhuang)訂較厚(hou)(hou)的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍(ji)，裝(zhuang)(zhuang)上書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)(ke)后有(you)(you)明顯的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)槽，翻閱方(fang)便。目前我國(guo)的(de)(de)精(jing)裝(zhuang)(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍(ji)多(duo)采用(yong)(yong)這種(zhong)圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)有(you)(you)脊(ji)(ji)的(de)(de)加工形式。圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)無脊(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)。圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)無脊(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)又(you)(you)稱圓(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)假脊(ji)(ji)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)背(bei)部呈(cheng)圓(yuan)(yuan)(yuan)(yuan)(yuan)弧形，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)與書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)的(de)(de)厚(hou)(hou)度相同(tong)，堅(jian)實挺括，但沒有(you)(you)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)裹(guo)背(bei)條脊(ji)(ji)。這種(zhong)形式的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)，一(yi)般常與軟質書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)(ke)或(huo)塑料壓(ya)制而成(cheng)的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼(ke)(ke)相配套。中(zhong)心紙有(you)(you)些機器(qi)還沒有(you)(you)沖圓(yuan)(yuan)(yuan)(yuan)(yuan)裝(zhuang)(zhuang)置(zhi)，即(ji)將方(fang)背(bei)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)先進行沖圓(yuan)(yuan)(yuan)(yuan)(yuan)加工，作初步定(ding)型。先根據書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)厚(hou)(hou)度和中(zhong)心紙幅面大小調定(ding)好夾書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)器(qi)及扒(ba)圓(yuan)(yuan)(yuan)(yuan)(yuan)輥（或(huo)沖圓(yuan)(yuan)(yuan)(yuan)(yuan)裝(zhuang)(zhuang)置(zhi)）的(de)(de)規(gui)矩，再使(shi)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)進入夾書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)器(qi)內并送到扒(ba)圓(yuan)(yuan)(yuan)(yuan)(yuan)輥之間，將書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)扒(ba)擠成(cheng)一(yi)定(ding)圓(yuan)(yuan)(yuan)(yuan)(yuan)勢。