什(shen)么(me)是裹背條，裹背條是通過皮殼機等機械(xie)用于(yu)精裝書本的書脊部分(fen)，使書貼(tie)連接得更(geng)加(jia)牢固。書脊制作弧長的計(ji)算，本器規格依書芯(xin)幅面大小進(jin)行(xing)調(diao)定，以能將書芯(xin)平穩地(di)送進(jin)夾書裝置內為標準。入本后的書冊不(bu)斜歪，四角垂直地(di)頂齊在夾書裝置的靠板(ban)、側規內。裁切(qie)尺寸正確一致，其質量要求(qiu)與(yu)規格誤差(cha)與(yu)一般切(qie)書相同。

夾(jia)書(shu)簽絲帶(dai)裝(zhuang)置安放在(zai)切書(shu)機(ji)與扒圓起脊(ji)機(ji)之間(jian)(jian)。即(ji)將(jiang)切完的(de)(de)書(shu)芯，用分本器(qi)從(cong)中(zhong)間(jian)(jian)分開，再由輸放絲帶(dai)器(qi)將(jiang)絲帶(dai)夾(jia)入中(zhong)心紙(zhi)書(shu)芯的(de)(de)中(zhong)間(jian)(jian)靠訂縫(feng)一邊(bian)(bian)。絲帶(dai)夾(jia)在(zai)書(shu)芯內兩端各留出粘邊(bian)(bian)和(he)使用的(de)(de)余地，再經(jing)切刀(dao)（剪刀(dao)式）將(jiang)其(qi)剪斷。

剪斷后的(de)(de)(de)(de)(de)絲帶(dai)(dai)，裹背(bei)(bei)(bei)(bei)條(tiao)芯(xin)部分(fen)被下面(mian)膠輥(gun)著膠、壓(ya)實完成夾書(shu)(shu)(shu)(shu)簽(qian)絲帶(dai)(dai)過程。書(shu)(shu)(shu)(shu)簽(qian)絲帶(dai)(dai)的(de)(de)(de)(de)(de)長(chang)(chang)度(du)與(yu)一般(ban)手工加(jia)(jia)工長(chang)(chang)度(du)基(ji)本相(xiang)同，可(ke)依書(shu)(shu)(shu)(shu)冊幅面(mian)長(chang)(chang)度(du)調定。扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)起(qi)脊(ji)(ji)操作(zuo)及(ji)要求(qiu)。書(shu)(shu)(shu)(shu)芯(xin)經裁切、夾粘(zhan)絲帶(dai)(dai)（或(huo)不(bu)夾粘(zhan)絲帶(dai)(dai)）后，繼續(xu)傳(chuan)送（或(huo)翻轉變(bian)位）并(bing)做90°翻轉，使平(ping)放書(shu)(shu)(shu)(shu)芯(xin)變(bian)為(wei)后背(bei)(bei)(bei)(bei)朝上(shang)（或(huo)朝下）而進入扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)起(qi)脊(ji)(ji)機。扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)起(qi)脊(ji)(ji)機的(de)(de)(de)(de)(de)加(jia)(jia)工，其(qi)操作(zuo)分(fen)為(wei)兩步，但(dan)機器的(de)(de)(de)(de)(de)結構是(shi)連在一起(qi)的(de)(de)(de)(de)(de)，均是(shi)先扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)后起(qi)脊(ji)(ji)。扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)。扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)起(qi)脊(ji)(ji)機在扒(ba)(ba)圓(yuan)(yuan)(yuan)(yuan)時，由一組（或(huo)一對）圓(yuan)(yuan)(yuan)(yuan)輥(gun)，將書(shu)(shu)(shu)(shu)芯(xin)壓(ya)緊后作(zuo)相(xiang)對旋轉動作(zuo)），使書(shu)(shu)(shu)(shu)背(bei)(bei)(bei)(bei)扒(ba)(ba)成適(shi)當規(gui)格(ge)圓(yuan)(yuan)(yuan)(yuan)勢，加(jia)(jia)工成圓(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)書(shu)(shu)(shu)(shu)芯(xin)。書(shu)(shu)(shu)(shu)芯(xin)書(shu)(shu)(shu)(shu)背(bei)(bei)(bei)(bei)的(de)(de)(de)(de)(de)形狀(zhuang)分(fen)為(wei)圓(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)有脊(ji)(ji)、圓(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)無脊(ji)(ji)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(tiao)書(shu)(shu)(shu)(shu)刊的(de)(de)(de)(de)(de)書(shu)(shu)(shu)(shu)脊(ji)(ji)不(bu)高出(chu)書(shu)(shu)(shu)(shu)芯(xin)平(ping)面(mian)，而精裝(zhuang)書(shu)(shu)(shu)(shu)刊的(de)(de)(de)(de)(de)書(shu)(shu)(shu)(shu)脊(ji)(ji)一般(ban)要高出(chu)書(shu)(shu)(shu)(shu)芯(xin)的(de)(de)(de)(de)(de)平(ping)面(mian)。書(shu)(shu)(shu)(shu)脊(ji)(ji)分(fen)為(wei)真脊(ji)(ji)和假脊(ji)(ji)。

真(zhen)脊(ji)是(shi)利用書(shu)(shu)(shu)(shu)(shu)背(bei)上下兩邊變形的(de)弧度高(gao)出書(shu)(shu)(shu)(shu)(shu)芯平面；假脊(ji)則是(shi)利用紙(zhi)板鑲在書(shu)(shu)(shu)(shu)(shu)背(bei)后形成的(de)書(shu)(shu)(shu)(shu)(shu)脊(ji)，書(shu)(shu)(shu)(shu)(shu)脊(ji)的(de)脊(ji)高(gao)等(deng)于封面紙(zhi)板的(de)厚度。方背(bei)書(shu)(shu)(shu)(shu)(shu)芯。是(shi)指書(shu)(shu)(shu)(shu)(shu)芯的(de)書(shu)(shu)(shu)(shu)(shu)背(bei)平直(zhi)方正。書(shu)(shu)(shu)(shu)(shu)背(bei)不突出，與平裝書(shu)(shu)(shu)(shu)(shu)刊的(de)書(shu)(shu)(shu)(shu)(shu)背(bei)基本相似(si)。

背(bei)(bei)(bei)(bei)(bei)與(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)上下環襯互成(cheng)直(zhi)角，由于(yu)精裝書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)是用鎖線訂(ding)訂(ding)連，每一(yi)個書(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖(tie)(tie)的訂(ding)口折縫里面都用線串過，因(yin)此(ci)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)背(bei)(bei)(bei)(bei)(bei)脊(ji)比書(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖(tie)(tie)其它部(bu)分(fen)要厚(hou)一(yi)些，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍的帖(tie)(tie)數越多，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊(ji)背(bei)(bei)(bei)(bei)(bei)與(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)其它部(bu)分(fen)厚(hou)度的差別(bie)也越大(da)。所以方(fang)背(bei)(bei)(bei)(bei)(bei)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)的形(xing)式一(yi)般(ban)只用于(yu)厚(hou)度約(yue)為20mm的精裝書(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍。圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)有(you)脊(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)。圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)有(you)脊(ji)又(you)稱圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)真(zhen)脊(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)。書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)背(bei)(bei)(bei)(bei)(bei)部(bu)呈(cheng)(cheng)圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)弧(hu)形(xing)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊(ji)高(gao)起有(you)脊(ji)壟，堅(jian)硬(ying)挺(ting)實，這種書(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)(bei)(bei)的形(xing)式適合于(yu)裝訂(ding)較厚(hou)的書(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍，裝上書(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼后(hou)有(you)明顯的書(shu)(shu)(shu)(shu)(shu)(shu)(shu)槽(cao)，翻閱方(fang)便。目(mu)前我國的精裝書(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍多采用這種圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)有(you)脊(ji)的加工形(xing)式。圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)無(wu)脊(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)。圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)無(wu)脊(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)又(you)稱圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)假脊(ji)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)背(bei)(bei)(bei)(bei)(bei)部(bu)呈(cheng)(cheng)圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)弧(hu)形(xing)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)(bei)(bei)與(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)的厚(hou)度相(xiang)同，堅(jian)實挺(ting)括，但沒有(you)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)裹背(bei)(bei)(bei)(bei)(bei)條(tiao)脊(ji)。這種形(xing)式的書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)，一(yi)般(ban)常與(yu)軟(ruan)質書(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼或(huo)塑料壓制而成(cheng)的書(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼相(xiang)配套。中(zhong)心(xin)紙有(you)些機器還沒有(you)沖(chong)圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)裝置(zhi)，即將方(fang)背(bei)(bei)(bei)(bei)(bei)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)先進(jin)行沖(chong)圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)加工，作初步定(ding)型。先根據(ju)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)厚(hou)度和中(zhong)心(xin)紙幅面大(da)小調定(ding)好(hao)夾(jia)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)器及扒圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)輥（或(huo)沖(chong)圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)裝置(zhi)）的規矩，再使書(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)進(jin)入夾(jia)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)器內并送(song)到(dao)扒圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)輥之間，將書(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)(bei)(bei)扒擠成(cheng)一(yi)定(ding)圓(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)勢。