什么是裹背條，裹背條是通過皮殼機等機械用(yong)于精裝書本的(de)書脊部分，使書貼連接(jie)得(de)更加牢固。書脊制作弧長(chang)的(de)計算，本器規格依書芯幅面(mian)大(da)小進行(xing)調定(ding)，以(yi)能將書芯平穩地(di)送進夾書裝置(zhi)(zhi)內(nei)為標準(zhun)。入(ru)本后的(de)書冊(ce)不(bu)斜歪，四角(jiao)垂直地(di)頂齊在夾書裝置(zhi)(zhi)的(de)靠(kao)板(ban)、側規內(nei)。裁切尺寸(cun)正確一(yi)致，其質量要求(qiu)與(yu)規格誤差(cha)與(yu)一(yi)般切書相(xiang)同。

夾書(shu)(shu)(shu)簽絲(si)帶(dai)(dai)裝置安(an)放(fang)在切書(shu)(shu)(shu)機與(yu)扒圓起脊機之間。即將(jiang)切完的(de)書(shu)(shu)(shu)芯，用(yong)分本器從中間分開(kai)，再由輸放(fang)絲(si)帶(dai)(dai)器將(jiang)絲(si)帶(dai)(dai)夾入(ru)中心紙書(shu)(shu)(shu)芯的(de)中間靠(kao)訂縫一邊。絲(si)帶(dai)(dai)夾在書(shu)(shu)(shu)芯內(nei)兩端各留(liu)出(chu)粘邊和使用(yong)的(de)余地，再經(jing)切刀(dao)（剪刀(dao)式）將(jiang)其(qi)剪斷。

剪斷后(hou)(hou)的(de)(de)絲帶(dai)(dai)，裹背(bei)(bei)(bei)條(tiao)芯(xin)部分(fen)(fen)被下面膠輥著膠、壓實(shi)完成夾書(shu)(shu)(shu)(shu)(shu)簽絲帶(dai)(dai)過程。書(shu)(shu)(shu)(shu)(shu)簽絲帶(dai)(dai)的(de)(de)長(chang)度與一般(ban)手工加工長(chang)度基本相同，可依(yi)書(shu)(shu)(shu)(shu)(shu)冊幅面長(chang)度調定。扒(ba)(ba)圓(yuan)起脊(ji)操(cao)作(zuo)及要求(qiu)。書(shu)(shu)(shu)(shu)(shu)芯(xin)經(jing)裁切、夾粘絲帶(dai)(dai)（或不夾粘絲帶(dai)(dai)）后(hou)(hou)，繼續傳送(song)（或翻轉變位）并(bing)做(zuo)90°翻轉，使(shi)平(ping)放(fang)書(shu)(shu)(shu)(shu)(shu)芯(xin)變為(wei)(wei)后(hou)(hou)背(bei)(bei)(bei)朝(chao)上（或朝(chao)下）而進(jin)入扒(ba)(ba)圓(yuan)起脊(ji)機。扒(ba)(ba)圓(yuan)起脊(ji)機的(de)(de)加工，其操(cao)作(zuo)分(fen)(fen)為(wei)(wei)兩步(bu)，但(dan)機器的(de)(de)結構是連在一起的(de)(de)，均是先扒(ba)(ba)圓(yuan)后(hou)(hou)起脊(ji)。扒(ba)(ba)圓(yuan)。扒(ba)(ba)圓(yuan)起脊(ji)機在扒(ba)(ba)圓(yuan)時，由一組（或一對(dui)）圓(yuan)輥，將書(shu)(shu)(shu)(shu)(shu)芯(xin)壓緊(jin)后(hou)(hou)作(zuo)相對(dui)旋轉動作(zuo)），使(shi)書(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)扒(ba)(ba)成適當規格(ge)圓(yuan)勢，加工成圓(yuan)背(bei)(bei)(bei)書(shu)(shu)(shu)(shu)(shu)芯(xin)。書(shu)(shu)(shu)(shu)(shu)芯(xin)書(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)的(de)(de)形狀分(fen)(fen)為(wei)(wei)圓(yuan)背(bei)(bei)(bei)有脊(ji)、圓(yuan)背(bei)(bei)(bei)無脊(ji)和方(fang)背(bei)(bei)(bei)（或稱平(ping)背(bei)(bei)(bei)）三種。平(ping)裝裹背(bei)(bei)(bei)條(tiao)書(shu)(shu)(shu)(shu)(shu)刊的(de)(de)書(shu)(shu)(shu)(shu)(shu)脊(ji)不高(gao)出(chu)書(shu)(shu)(shu)(shu)(shu)芯(xin)平(ping)面，而精裝書(shu)(shu)(shu)(shu)(shu)刊的(de)(de)書(shu)(shu)(shu)(shu)(shu)脊(ji)一般(ban)要高(gao)出(chu)書(shu)(shu)(shu)(shu)(shu)芯(xin)的(de)(de)平(ping)面。書(shu)(shu)(shu)(shu)(shu)脊(ji)分(fen)(fen)為(wei)(wei)真脊(ji)和假(jia)脊(ji)。

真脊是利用書背(bei)(bei)上下兩邊變形(xing)的弧度高(gao)出書芯(xin)平面(mian)；假脊則是利用紙(zhi)板鑲在(zai)書背(bei)(bei)后形(xing)成的書脊，書脊的脊高(gao)等于封(feng)面(mian)紙(zhi)板的厚度。方(fang)背(bei)(bei)書芯(xin)。是指書芯(xin)的書背(bei)(bei)平直方(fang)正。書背(bei)(bei)不突出，與平裝書刊的書背(bei)(bei)基本相似。

背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)與(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)上下環襯互成直角，由于精裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)是用(yong)(yong)(yong)鎖線(xian)訂(ding)訂(ding)連，每一個書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖(tie)的(de)(de)訂(ding)口折縫里面(mian)都用(yong)(yong)(yong)線(xian)串過，因此，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)脊(ji)(ji)比書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)帖(tie)其它(ta)部(bu)分要厚一些(xie)(xie)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍的(de)(de)帖(tie)數越(yue)多(duo)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊(ji)(ji)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)與(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)其它(ta)部(bu)分厚度(du)的(de)(de)差別也越(yue)大。所以方背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)的(de)(de)形(xing)(xing)(xing)式一般只用(yong)(yong)(yong)于厚度(du)約(yue)為20mm的(de)(de)精裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍。圓(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)有(you)(you)脊(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)。圓(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)有(you)(you)脊(ji)(ji)又稱(cheng)圓(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)真脊(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)。書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)部(bu)呈圓(yuan)(yuan)弧形(xing)(xing)(xing)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)脊(ji)(ji)高起有(you)(you)脊(ji)(ji)壟，堅硬挺實(shi)，這種(zhong)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)的(de)(de)形(xing)(xing)(xing)式適(shi)合(he)于裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)訂(ding)較厚的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍，裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)上書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼后(hou)有(you)(you)明顯的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)槽，翻閱方便。目前我國(guo)的(de)(de)精裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)籍多(duo)采用(yong)(yong)(yong)這種(zhong)圓(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)有(you)(you)脊(ji)(ji)的(de)(de)加工(gong)形(xing)(xing)(xing)式。圓(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)無脊(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)。圓(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)無脊(ji)(ji)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)又稱(cheng)圓(yuan)(yuan)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)假脊(ji)(ji)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)部(bu)呈圓(yuan)(yuan)弧形(xing)(xing)(xing)，書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)與(yu)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)的(de)(de)厚度(du)相同，堅實(shi)挺括，但沒有(you)(you)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)裹背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)條脊(ji)(ji)。這種(zhong)形(xing)(xing)(xing)式的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)，一般常(chang)與(yu)軟質書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼或塑料壓(ya)制而成的(de)(de)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)殼相配套。中心紙(zhi)有(you)(you)些(xie)(xie)機器還沒有(you)(you)沖(chong)圓(yuan)(yuan)裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)置，即將(jiang)方背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)先(xian)進行沖(chong)圓(yuan)(yuan)加工(gong)，作初(chu)步(bu)定(ding)型。先(xian)根據書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)厚度(du)和中心紙(zhi)幅(fu)面(mian)大小調定(ding)好夾書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)器及(ji)扒(ba)圓(yuan)(yuan)輥（或沖(chong)圓(yuan)(yuan)裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)置）的(de)(de)規(gui)矩，再使書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)芯(xin)(xin)(xin)(xin)進入夾書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)器內并送(song)到扒(ba)圓(yuan)(yuan)輥之間(jian)，將(jiang)書(shu)(shu)(shu)(shu)(shu)(shu)(shu)(shu)背(bei)(bei)(bei)(bei)(bei)(bei)(bei)(bei)扒(ba)擠成一定(ding)圓(yuan)(yuan)勢(shi)。