本(ben)發明涉及一種電路板技術領域,具體是一種雙面板混裝貼裝工藝。
背景技術:
PCB板(ban)(ban)(ban)(ban)又稱(cheng)電(dian)路(lu)(lu)(lu)(lu)板(ban)(ban)(ban)(ban)、印(yin)刷電(dian)路(lu)(lu)(lu)(lu)板(ban)(ban)(ban)(ban)等。PCB板(ban)(ban)(ban)(ban)使電(dian)路(lu)(lu)(lu)(lu)迷你化(hua)、直(zhi)觀化(hua),對于固定電(dian)路(lu)(lu)(lu)(lu)的(de)(de)批(pi)量(liang)生產(chan)和優(you)化(hua)用(yong)(yong)電(dian)器布局(ju)起重要(yao)作用(yong)(yong)。線(xian)(xian)(xian)路(lu)(lu)(lu)(lu)板(ban)(ban)(ban)(ban)按層數來(lai)分(fen)(fen)的(de)(de)話分(fen)(fen)為單面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)板(ban)(ban)(ban)(ban),雙(shuang)面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)板(ban)(ban)(ban)(ban),和多層線(xian)(xian)(xian)路(lu)(lu)(lu)(lu)板(ban)(ban)(ban)(ban)三個(ge)大的(de)(de)分(fen)(fen)類。單面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)板(ban)(ban)(ban)(ban),在(zai)(zai)最基本的(de)(de)PCB上(shang)(shang)(shang),零件集(ji)(ji)中(zhong)在(zai)(zai)其中(zhong)一面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian),導(dao)線(xian)(xian)(xian)則集(ji)(ji)中(zhong)在(zai)(zai)另(ling)一面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)上(shang)(shang)(shang)。因(yin)為導(dao)線(xian)(xian)(xian)只出(chu)現在(zai)(zai)其中(zhong)一面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian),所(suo)(suo)以(yi)就稱(cheng)這種PCB叫作單面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)線(xian)(xian)(xian)路(lu)(lu)(lu)(lu)板(ban)(ban)(ban)(ban)。雙(shuang)面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)板(ban)(ban)(ban)(ban)是單面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)板(ban)(ban)(ban)(ban)的(de)(de)延伸,當單層布線(xian)(xian)(xian)不能滿足電(dian)子產(chan)品的(de)(de)需要(yao)時,就要(yao)使用(yong)(yong)雙(shuang)面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)板(ban)(ban)(ban)(ban)了。雙(shuang)面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)板(ban)(ban)(ban)(ban)雙(shuang)面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)都(dou)有(you)(you)覆銅有(you)(you)走線(xian)(xian)(xian),并(bing)且(qie)可以(yi)通(tong)過過孔(kong)來(lai)導(dao)通(tong)兩層之(zhi)間(jian)的(de)(de)線(xian)(xian)(xian)路(lu)(lu)(lu)(lu),使之(zhi)形成(cheng)所(suo)(suo)需要(yao)的(de)(de)網絡連(lian)接。這種電(dian)路(lu)(lu)(lu)(lu)板(ban)(ban)(ban)(ban)的(de)(de)兩面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)都(dou)有(you)(you)布線(xian)(xian)(xian)。不過要(yao)用(yong)(yong)上(shang)(shang)(shang)兩面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)的(de)(de)導(dao)線(xian)(xian)(xian),必須要(yao)在(zai)(zai)兩面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)間(jian)有(you)(you)適當的(de)(de)電(dian)路(lu)(lu)(lu)(lu)連(lian)接才行。這種電(dian)路(lu)(lu)(lu)(lu)間(jian)的(de)(de)橋梁叫做導(dao)孔(kong)。導(dao)孔(kong)是在(zai)(zai)PCB上(shang)(shang)(shang),充滿或涂上(shang)(shang)(shang)金(jin)屬的(de)(de)小(xiao)洞(dong),它(ta)可以(yi)與兩面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)的(de)(de)導(dao)線(xian)(xian)(xian)相連(lian)接。因(yin)為雙(shuang)面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)板(ban)(ban)(ban)(ban)的(de)(de)面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)積比(bi)(bi)單面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)板(ban)(ban)(ban)(ban)大了一倍,而且(qie)因(yin)為布線(xian)(xian)(xian)可以(yi)互(hu)相交錯,可以(yi)繞(rao)到另(ling)一面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian),它(ta)更適合用(yong)(yong)在(zai)(zai)比(bi)(bi)單面(mian)(mian)(mian)(mian)(mian)(mian)(mian)(mian)板(ban)(ban)(ban)(ban)更復(fu)雜的(de)(de)電(dian)路(lu)(lu)(lu)(lu)上(shang)(shang)(shang)。
一(yi)個(ge)(ge)完整(zheng)的(de)(de)(de)(de)(de)PCB制作(zuo)流(liu)程是:PCB設(she)計、裸板制作(zuo)、再經過實裝(zhuang)(zhuang)(zhuang)(zhuang)技術(shu)焊(han)(han)(han)接,PCB實裝(zhuang)(zhuang)(zhuang)(zhuang)流(liu)程又(you)分為(wei)表面(mian)(mian)(mian)(mian)貼裝(zhuang)(zhuang)(zhuang)(zhuang)和混(hun)裝(zhuang)(zhuang)(zhuang)(zhuang)兩大(da)類,表面(mian)(mian)(mian)(mian)貼裝(zhuang)(zhuang)(zhuang)(zhuang)技術(shu)也(ye)稱SMT,是目前電(dian)(dian)子(zi)組(zu)裝(zhuang)(zhuang)(zhuang)(zhuang)行(xing)業(ye)里最流(liu)行(xing)的(de)(de)(de)(de)(de)一(yi)種(zhong)技術(shu)和工藝。傳(chuan)統的(de)(de)(de)(de)(de)元(yuan)(yuan)(yuan)(yuan)件(jian)(jian)(jian)(jian)的(de)(de)(de)(de)(de)封裝(zhuang)(zhuang)(zhuang)(zhuang)形式(shi)主要是插腳(jiao)封裝(zhuang)(zhuang)(zhuang)(zhuang)和扁(bian)平(ping)封裝(zhuang)(zhuang)(zhuang)(zhuang),現在(zai)這些(xie)傳(chuan)統封裝(zhuang)(zhuang)(zhuang)(zhuang)的(de)(de)(de)(de)(de)元(yuan)(yuan)(yuan)(yuan)件(jian)(jian)(jian)(jian)具有一(yi)定的(de)(de)(de)(de)(de)弊端(duan),越(yue)(yue)來越(yue)(yue)不(bu)(bu)被人(ren)們重視。插腳(jiao)封裝(zhuang)(zhuang)(zhuang)(zhuang),要求(qiu)在(zai)印(yin)(yin)制板上(shang)打(da)孔(kong),把插腳(jiao)切短,上(shang)錫(xi),插入(ru)印(yin)(yin)制背(bei)面(mian)(mian)(mian)(mian)再進行(xing)焊(han)(han)(han)接,其中大(da)量的(de)(de)(de)(de)(de)都是手工操作(zuo);扁(bian)平(ping)封裝(zhuang)(zhuang)(zhuang)(zhuang)則不(bu)(bu)僅要求(qiu)在(zai)印(yin)(yin)制板上(shang)打(da)孔(kong),還要在(zai)板上(shang)按(an)照元(yuan)(yuan)(yuan)(yuan)件(jian)(jian)(jian)(jian)尺寸開一(yi)小(xiao)(xiao)窗(chuang)口(kou)(kou),將(jiang)(jiang)元(yuan)(yuan)(yuan)(yuan)件(jian)(jian)(jian)(jian)引線(xian)折(zhe)彎(wan)90°,將(jiang)(jiang)元(yuan)(yuan)(yuan)(yuan)件(jian)(jian)(jian)(jian)放(fang)入(ru)窗(chuang)口(kou)(kou)內(nei)。而折(zhe)彎(wan)引線(xian)很(hen)可能(neng)會(hui)損傷玻珠至金(jin)屬殼(ke)體間(jian)的(de)(de)(de)(de)(de)密封性(xing),從(cong)而將(jiang)(jiang)引線(xian)插入(ru)小(xiao)(xiao)孔(kong)并將(jiang)(jiang)元(yuan)(yuan)(yuan)(yuan)件(jian)(jian)(jian)(jian)放(fang)入(ru)窗(chuang)口(kou)(kou)內(nei)都是很(hen)繁雜的(de)(de)(de)(de)(de)加工。表面(mian)(mian)(mian)(mian)貼裝(zhuang)(zhuang)(zhuang)(zhuang)技術(shu)它是一(yi)種(zhong)將(jiang)(jiang)無引腳(jiao)或短引線(xian)表面(mian)(mian)(mian)(mian)組(zu)裝(zhuang)(zhuang)(zhuang)(zhuang)元(yuan)(yuan)(yuan)(yuan)器件(jian)(jian)(jian)(jian)安(an)裝(zhuang)(zhuang)(zhuang)(zhuang)在(zai)印(yin)(yin)制電(dian)(dian)路板的(de)(de)(de)(de)(de)表面(mian)(mian)(mian)(mian)或其它基(ji)板的(de)(de)(de)(de)(de)表面(mian)(mian)(mian)(mian)上(shang),通過回流(liu)焊(han)(han)(han)或浸(jin)焊(han)(han)(han)等方法(fa)加以焊(han)(han)(han)接組(zu)裝(zhuang)(zhuang)(zhuang)(zhuang)的(de)(de)(de)(de)(de)電(dian)(dian)路裝(zhuang)(zhuang)(zhuang)(zhuang)連技術(shu),是一(yi)種(zhong)無需(xu)對(dui)印(yin)(yin)制板鉆插裝(zhuang)(zhuang)(zhuang)(zhuang)孔(kong),直接將(jiang)(jiang)表面(mian)(mian)(mian)(mian)組(zu)裝(zhuang)(zhuang)(zhuang)(zhuang)元(yuan)(yuan)(yuan)(yuan)器件(jian)(jian)(jian)(jian)貼、焊(han)(han)(han)到印(yin)(yin)制板表面(mian)(mian)(mian)(mian)規(gui)定位置上(shang)的(de)(de)(de)(de)(de)裝(zhuang)(zhuang)(zhuang)(zhuang)聯技術(shu)。使(shi)用表面(mian)(mian)(mian)(mian)安(an)裝(zhuang)(zhuang)(zhuang)(zhuang),由(you)于(yu)引線(xian)的(de)(de)(de)(de)(de)縮短,相(xiang)對(dui)插腳(jiao)元(yuan)(yuan)(yuan)(yuan)件(jian)(jian)(jian)(jian)而言,可以大(da)大(da)降(jiang)低引線(xian)電(dian)(dian)感,寄生電(dian)(dian)容(rong)和電(dian)(dian)阻,因(yin)而各個(ge)(ge)元(yuan)(yuan)(yuan)(yuan)件(jian)(jian)(jian)(jian)的(de)(de)(de)(de)(de)延(yan)遲時間(jian)縮短,使(shi)電(dian)(dian)路有更(geng)快的(de)(de)(de)(de)(de)響應速度,使(shi)系統的(de)(de)(de)(de)(de)電(dian)(dian)性(xing)能(neng)獲得較(jiao)大(da)提高;
在(zai)PCB板(ban)制(zhi)作過程中,混裝(zhuang)(zhuang)(zhuang)(zhuang)是指即有(you)貼裝(zhuang)(zhuang)(zhuang)(zhuang)又有(you)插裝(zhuang)(zhuang)(zhuang)(zhuang)的組裝(zhuang)(zhuang)(zhuang)(zhuang)方式(shi),結合(he)(he)了(le)貼裝(zhuang)(zhuang)(zhuang)(zhuang)和(he)插裝(zhuang)(zhuang)(zhuang)(zhuang)的優勢越來(lai)越受(shou)到企業的灌注(zhu),現有(you)技(ji)術中的雙面板(ban)混裝(zhuang)(zhuang)(zhuang)(zhuang)貼片(pian)工(gong)藝(yi)存在(zai)工(gong)藝(yi)復雜,產品合(he)(he)格率(lv)低(di),效率(lv)低(di),貼片(pian)膠的粘結強度(du)低(di),固化(hua)速度(du)慢(man)等缺陷,尤其是對于(yu)一些采用的PCB板(ban)較大(da),元件眾多,集成度(du)高的產品,如不能保證貼片(pian)質量,則會影響到生(sheng)產效率(lv)和(he)產品合(he)(he)格率(lv),簡(jian)接提高生(sheng)產成本。
技術實現要素:
本發明的(de)目的(de)在于提供一種雙面板(ban)混裝貼(tie)裝工(gong)藝,以(yi)解決上述背景技術中提出(chu)的(de)問題。
為實現上述目的,本發(fa)明(ming)提供如下技術方(fang)案(an):
一(yi)種雙面板混裝(zhuang)(zhuang)貼裝(zhuang)(zhuang)工(gong)藝,其(qi)步驟如下:
S1:B面(mian)印(yin)刷錫(xi)膏;以鋼網作為印(yin)刷版,在刮(gua)刀推動下(xia)把錫(xi)膏印(yin)刷到(dao)PCB板上B面(mian)的焊盤上;
S2:B面(mian)(mian)貼裝元件(jian);將表(biao)面(mian)(mian)組(zu)裝元器件(jian)準確安裝到PCB板的B面(mian)(mian)固(gu)定位(wei)置上;
S3:B面(mian)回流焊(han);在待(dai)連接的表面(mian)施(shi)以焊(han)膏和溶劑,把元器件放在他們的位(wei)置上,然(ran)后增溫加熱使焊(han)膏融(rong)化,使表面(mian)組(zu)裝元器件與(yu)PCB板B面(mian)牢固粘接在一起(qi);
S4:翻轉(zhuan);翻轉(zhuan)電路(lu)板(ban),繼(ji)續進(jin)行A面的印刷;
S5:A面印刷(shua)錫(xi)膏;以鋼網作為(wei)印刷(shua)版,在刮刀推動下把錫(xi)膏印刷(shua)到PCB板(ban)上A面的焊(han)盤上;
S6:A面貼裝元件;是將(jiang)表(biao)面組裝元器(qi)件準(zhun)確安裝到PCB板的A面固定(ding)位(wei)置上;
S7:A面(mian)(mian)回(hui)流焊;在(zai)待連接的表面(mian)(mian)施以焊膏和溶劑,把元器(qi)件放在(zai)他們(men)的位(wei)置上,然(ran)后(hou)增溫(wen)加熱使焊膏融化(hua)(hua),加溫(wen)將焊膏融化(hua)(hua),使表面(mian)(mian)組裝元器(qi)件與PCB板A面(mian)(mian)牢固粘接在(zai)一起;
S8:波峰焊(han);將熔化(hua)的鉛錫合金,經電動泵或(huo)電磁(ci)泵噴流成設計要(yao)求的焊(han)料波峰,使預先(xian)裝有(you)元(yuan)器(qi)件的印制板通過焊(han)料波峰,實現元(yuan)器(qi)件焊(han)端或(huo)引腳(jiao)與印制板焊(han)盤之間焊(han)接;波峰焊(han)需要(yao)在波峰焊(han)機上(shang)完成,所述波峰焊(han)錫機主要(yao)由運輸帶,助焊(han)劑添加區(qu),預熱區(qu)和波峰錫爐組成。
作為(wei)本發明(ming)進一步(bu)的方案,步(bu)驟(zou)S1和(he)S5具體(ti)步(bu)驟(zou)均如下:
S101:安裝(zhuang)模(mo)板和刮(gua)(gua)刀(dao):應(ying)先(xian)安裝(zhuang)模(mo)板后安裝(zhuang)刮(gua)(gua)刀(dao);先(xian)裝(zhuang)后刮(gua)(gua)刀(dao),后裝(zhuang)前刮(gua)(gua)刀(dao);模(mo)板應(ying)
插入模板軌道上(shang)并推到最后位置卡緊;
S102:PCB板(ban)定(ding)位;使PCB板(ban)初(chu)步(bu)調整到與模板(ban)圖形相(xiang)對應的(de)位置上;
S103:圖形對準;通過(guo)對工作臺或對模(mo)(mo)板(ban)精細調整,使PCB的焊盤圖形與(yu)模(mo)(mo)板(ban)漏孔圖形
完全重合;
S104:將錫(xi)膏(gao)添(tian)加進入錫(xi)膏(gao)印(yin)刷機,然后(hou)開始印(yin)刷。
作為本發明再進(jin)一步(bu)(bu)(bu)的方案:步(bu)(bu)(bu)驟(zou)S3和(he)S7具體步(bu)(bu)(bu)驟(zou)均(jun)如下(xia):
S301:增溫至(zhi)90℃-110℃時溶劑(ji)蒸(zheng)發;
S302:增(zeng)溫至焊劑(ji)的熔化(hua)(hua)點,助熔劑(ji)分解(jie)金屬(shu)氧化(hua)(hua)物;
S303:繼續增溫(wen),使漿狀焊劑微粒熔化并在焊接面(mian)開始(shi)沾化和(he)吸附;
S304:增溫至峰(feng)值,表(biao)面張力形成充分熔融焊劑的輪廓。
作為(wei)本發明(ming)再(zai)進一步(bu)的方(fang)案(an):步(bu)驟S8具(ju)體步(bu)驟如下:
S801:將(jiang)元(yuan)件(jian)插(cha)入(ru)(ru)電路板(ban)上相應的(de)元(yuan)件(jian)孔中:并將(jiang)已插(cha)元(yuan)器(qi)件(jian)的(de)電路板(ban)嵌入(ru)(ru)治具,在傳送(song)帶作(zuo)用下將(jiang)已插(cha)好元(yuan)器(qi)件(jian)的(de)電路板(ban),由機(ji)器(qi)入(ru)(ru)口處的(de)接駁裝置送(song)入(ru)(ru)波峰焊(han)機(ji)內;
S802:預涂助焊劑(ji):進(jin)入助焊劑(ji)添加區(qu),助焊劑(ji)添加區(qu)由(you)紅(hong)外(wai)線感應器(qi)及噴嘴組成,經紅(hong)外(wai)線感應器(qi)感應,以判斷線路板(ban)是(shi)否進(jin)入,并測量出線路板(ban)的寬度(du),然后噴嘴沿著治具的起始位(wei)置(zhi)來回(hui)勻速噴霧,使電(dian)路板(ban)的裸露焊盤表面、焊盤過孔以及元器(qi)件引腳表面均勻地(di)涂敷一層(ceng)助焊劑(ji);
S803:PCB板(ban)預(yu)加熱(re):進入(ru)預(yu)熱(re)區(qu),PCB板(ban)焊接部位被加熱(re)到(dao)潤濕溫(wen)度,同時,由于元器件(jian)溫(wen)度的升(sheng)高(gao),避免(mian)了浸入(ru)熔融焊料時受(shou)到(dao)熱(re)沖(chong)擊;
S804:波峰(feng)(feng)焊(han):進入波峰(feng)(feng)焊(han)錫爐,共經歷兩個波峰(feng)(feng)第一波峰(feng)(feng)為擾流(liu)波,焊(han)料通(tong)過(guo)狹縫(feng)滲入,從而透(tou)入間隙,噴射方向與(yu)電路板進行(xing)方向相同;第二波峰(feng)(feng)為平流(liu)波,焊(han)錫流(liu)動速度(du)低于擾流(liu)波速度(du),并(bing)且能(neng)有效去除端子上的(de)過(guo)量(liang)焊(han)錫,使(shi)所有的(de)焊(han)接(jie)面潤濕良好,并(bing)能(neng)對第一波峰(feng)(feng)造(zao)成的(de)拉(la)尖和橋接(jie)進行(xing)充分的(de)修正;
S805:冷卻:制冷系統使PCB板的溫度下降;
S806:切(qie)除多余插件腳。
與(yu)現有(you)技術相(xiang)比(bi),本發明的(de)有(you)益效果是:
雙面板(ban)混裝貼裝工藝,工藝簡單,產(chan)品合(he)格(ge)率高(gao),效率高(gao),固化速(su)度(du)(du)快(kuai),尤其(qi)是對于(yu)一些采(cai)用(yong)的PCB板(ban)較大(da),元件(jian)眾多,集成度(du)(du)高(gao)的產(chan)品,其(qi)生產(chan)效率和(he)產(chan)品合(he)格(ge)率都大(da)幅度(du)(du)提(ti)高(gao),從而間(jian)接(jie)降低了生產(chan)成本。
附圖說明
圖1為一種雙面板混裝貼裝工藝的流(liu)程圖。
具體實施方式
下面(mian)結(jie)合具體實施方(fang)式(shi)對(dui)本發明(ming)的技術(shu)方(fang)案(an)作(zuo)進一步詳細地說明(ming)。
一種(zhong)雙面板混(hun)裝貼裝工(gong)藝,步驟如下:
S1:B面(mian)印(yin)刷(shua)(shua)錫(xi)膏(gao)(gao);以(yi)鋼網作為印(yin)刷(shua)(shua)版,在刮刀推(tui)動下把(ba)錫(xi)膏(gao)(gao)印(yin)刷(shua)(shua)到PCB板上B面(mian)的(de)焊盤上,所用(yong)設備為錫(xi)膏(gao)(gao)印(yin)刷(shua)(shua)機,錫(xi)膏(gao)(gao)印(yin)刷(shua)(shua)機位于SMT生產線的(de)最前端(duan);
S2:B面(mian)貼裝(zhuang)元件;是(shi)將表面(mian)組裝(zhuang)元器件準(zhun)確安裝(zhuang)到PCB板的B面(mian)固(gu)定位置上。所用(yong)設(she)備為貼片機(ji),貼片機(ji)安裝(zhuang)在(zai)SMT生(sheng)產線中印刷(shua)機(ji)的后面(mian)。
S3:B面回流焊;在(zai)待連接(jie)的(de)表(biao)(biao)面施以可控量的(de)焊膏和溶劑,然(ran)后把元器(qi)件放(fang)在(zai)他們的(de)位置上(shang),然(ran)后增溫(wen)加(jia)熱使焊膏融化,使表(biao)(biao)面組裝(zhuang)元器(qi)件與PCB板B面牢固粘接(jie)在(zai)一起。所用設備為回流焊爐(lu),回流焊爐(lu)位于SMT生產線中貼片機(ji)的(de)后面;
S4:翻轉;翻轉電路板(ban),繼續進行A面(mian)的印(yin)刷;
S5:A面(mian)印刷(shua)錫膏(gao);以鋼網作為(wei)印刷(shua)版(ban),在刮刀推動下(xia)把錫膏(gao)印刷(shua)到PCB板上(shang)A面(mian)的(de)焊盤上(shang);
S6:A面貼裝(zhuang)元件(jian);是(shi)將表面組裝(zhuang)元器件(jian)準確安裝(zhuang)到PCB板的A面固定位(wei)置上(shang)
S7:A面回流(liu)焊(han);在待連接(jie)的表面施以可控量的焊(han)膏和溶(rong)劑,然后把元(yuan)器(qi)件(jian)放在他們的位置上。然后增溫加(jia)熱(re)使焊(han)膏融化,加(jia)溫將(jiang)焊(han)膏融化,使表面組(zu)裝元(yuan)器(qi)件(jian)與(yu)PCB板A面牢(lao)固粘接(jie)在一(yi)起。
S8:波(bo)(bo)(bo)峰(feng)(feng)(feng)焊(han)(han)(han)(han);將熔(rong)化的(de)(de)軟釬焊(han)(han)(han)(han)料一(yi)般為鉛錫(xi)合(he)金,經電(dian)動泵(beng)或電(dian)磁(ci)泵(beng)噴流(liu)成設計要(yao)求的(de)(de)焊(han)(han)(han)(han)料波(bo)(bo)(bo)峰(feng)(feng)(feng),使預先裝(zhuang)有元(yuan)器件(jian)的(de)(de)印制板通過焊(han)(han)(han)(han)料波(bo)(bo)(bo)峰(feng)(feng)(feng),實(shi)現元(yuan)器件(jian)焊(han)(han)(han)(han)端(duan)或引腳與印制板焊(han)(han)(han)(han)盤之間焊(han)(han)(han)(han)接;波(bo)(bo)(bo)峰(feng)(feng)(feng)焊(han)(han)(han)(han)焊(han)(han)(han)(han)料溫度比在回流(liu)焊(han)(han)(han)(han)方法中使用的(de)(de)峰(feng)(feng)(feng)值(zhi)溫度高一(yi)些,典型(xing)值(zhi)是260℃;波(bo)(bo)(bo)峰(feng)(feng)(feng)焊(han)(han)(han)(han)需要(yao)在波(bo)(bo)(bo)峰(feng)(feng)(feng)焊(han)(han)(han)(han)機(ji)(ji)上完成,波(bo)(bo)(bo)峰(feng)(feng)(feng)焊(han)(han)(han)(han)錫(xi)機(ji)(ji)主要(yao)由運輸帶,助(zhu)焊(han)(han)(han)(han)劑添加區(qu),預熱(re)區(qu)和波(bo)(bo)(bo)峰(feng)(feng)(feng)錫(xi)爐組成。
印刷錫膏的具體(ti)(ti)流程即步(bu)驟(zou)S1和S5的具體(ti)(ti)步(bu)驟(zou)如下:
S101:安(an)裝模板(ban)和刮刀(dao)(dao),應先安(an)裝模板(ban)后(hou)安(an)裝刮刀(dao)(dao);先裝后(hou)刮刀(dao)(dao),后(hou)裝前(qian)刮刀(dao)(dao);模板(ban)應插入模板(ban)軌道上并(bing)推到(dao)最后(hou)位置卡緊;刮刀(dao)(dao)一(yi)般選用不銹(xiu)鋼(gang)刮刀(dao)(dao),特別是高密度印刷(shua)時,不銹(xiu)鋼(gang)刮刀(dao)(dao)有利于提(ti)高印刷(shua)精(jing)度;
S102:PCB板定位(wei)(wei);使PCB板初步調整到與模板圖(tu)形相對應的(de)位(wei)(wei)置上;
S103:圖形對(dui)準;通過對(dui)工作臺或對(dui)模板精細調整,使(shi)PCB的焊(han)盤圖形與(yu)模板漏孔圖形完全重(zhong)合;
S104:將錫膏添加進入錫膏印刷機,然后開始(shi)印刷,添加的(de)(de)原則是(shi)要(yao)高于(yu)刮刀的(de)(de)三分一的(de)(de)位置;
回流焊受熱作用過程的(de)溫度(du)變化過程即步驟S3和(he)S7的(de)具體(ti)步驟如下:
S301:溫度(du)達到(dao)大約(yue)90℃-110℃時溶劑(ji)蒸(zheng)發(fa)。
S302:隨著(zhu)溫(wen)度(du)升至焊劑(ji)的熔(rong)化點,典型值是183℃,助熔(rong)劑(ji)分解金屬氧化物。
S303:當溫度(du)繼續上升,漿狀焊(han)劑微粒熔化(hua)(hua)并在焊(han)接面(mian)開始(shi)沾化(hua)(hua)和吸附。
S304:溫度達到峰值,大約215℃時(shi)(shi),表面張力(li)形成充分(fen)熔融焊劑(ji)的輪廓。在該(gai)溫度,焊劑(ji)完全沾化只需(xu)幾(ji)秒鐘(zhong)的時(shi)(shi)間,工作在200℃以上的實際時(shi)(shi)間長(chang)度限制到1或2分(fen)鐘(zhong),以免損(sun)壞。
波峰焊的(de)具體(ti)流程即(ji)步(bu)驟S8的(de)具體(ti)步(bu)驟如(ru)下(xia):
S801:將(jiang)(jiang)元(yuan)(yuan)件插(cha)入(ru)電路(lu)(lu)板上相應的(de)(de)元(yuan)(yuan)件孔中:并將(jiang)(jiang)已(yi)插(cha)元(yuan)(yuan)器件的(de)(de)電路(lu)(lu)板嵌入(ru)治(zhi)具,在傳(chuan)送帶作用下將(jiang)(jiang)已(yi)插(cha)好元(yuan)(yuan)器件的(de)(de)電路(lu)(lu)板,由機器入(ru)口處(chu)的(de)(de)接(jie)駁裝置以一定的(de)(de)傾角和(he)傳(chuan)送速度(du)送入(ru)波峰焊機內;
S802:預涂(tu)助(zhu)(zhu)(zhu)焊劑(ji):進(jin)入助(zhu)(zhu)(zhu)焊劑(ji)添(tian)加區,助(zhu)(zhu)(zhu)焊劑(ji)添(tian)加區主(zhu)要是由紅外線(xian)(xian)感應(ying)器(qi)及噴(pen)嘴組(zu)成(cheng),經紅外線(xian)(xian)感應(ying)器(qi)感應(ying),以(yi)(yi)判斷線(xian)(xian)路板(ban)是否(fou)進(jin)入,并測量出(chu)線(xian)(xian)路板(ban)的(de)(de)(de)寬度,然后噴(pen)嘴沿著治具(ju)的(de)(de)(de)起始位置來回(hui)勻速噴(pen)霧,使(shi)電路板(ban)的(de)(de)(de)裸露焊盤表面(mian)、焊盤過(guo)孔以(yi)(yi)及元器(qi)件引腳表面(mian)均(jun)勻地涂(tu)敷一層薄薄的(de)(de)(de)助(zhu)(zhu)(zhu)焊劑(ji),助(zhu)(zhu)(zhu)焊劑(ji)的(de)(de)(de)作用是在線(xian)(xian)路板(ban)的(de)(de)(de)焊接(jie)面(mian)上形成(cheng)以(yi)(yi)保護膜;
S803:PCB板預(yu)加(jia)熱:進入預(yu)熱區,PCB板焊接部位被(bei)加(jia)熱到潤(run)濕溫(wen)度(du),同時,由于元器件溫(wen)度(du)的(de)升高,避(bi)免了浸入熔融焊料時受到大的(de)熱沖(chong)擊。預(yu)熱階(jie)段,PCB表面(mian)的(de)溫(wen)度(du)應在(zai)75~110℃之間(jian)為宜。
S804:波峰(feng)焊:進入波峰(feng)焊錫(xi)爐(lu),共(gong)經歷兩(liang)個波峰(feng)第(di)一波峰(feng)為擾(rao)流(liu)波,焊料以較高速通過狹縫滲入,從而(er)透入窄(zhai)小間隙(xi),噴射方向(xiang)與電路(lu)板進行方向(xiang)相同,擾(rao)流(liu)波能防(fang)止漏焊,它保證穿過電路(lu)板的(de)焊料分布適當;第(di)二波峰(feng)為平流(liu)波,焊錫(xi)流(liu)動速度慢一點(dian),能有效去除端(duan)子(zi)上(shang)的(de)過量焊錫(xi),使所(suo)有的(de)焊接面潤(run)濕良好,并能對第(di)一波峰(feng)造成的(de)拉尖和橋接進行充(chong)分的(de)修(xiu)正。
S805:冷卻(que):制冷系統使PCB板的溫度(du)急(ji)劇下(xia)降(jiang),目的是改善生產時產生的空泡(pao)及(ji)焊盤剝離(li)問題。
S806:切除多余(yu)插(cha)件(jian)腳。根據印刷版的(de)厚度(du)與所留元(yuan)件(jian)引線的(de)長度(du)調整刀(dao)片的(de)高(gao)低,然后(hou)將刀(dao)片架擰(ning)緊且平(ping)穩(wen),開機目測(ce)刀(dao)片的(de)旋轉情況,最后(hou)檢查保險裝置有(you)無失靈;
上面(mian)對本(ben)發明(ming)的(de)(de)較(jiao)佳實施方式(shi)作了詳細說明(ming),但是本(ben)發明(ming)并不限于上述實施方式(shi),在本(ben)領(ling)域的(de)(de)普通技(ji)術人員所(suo)具備的(de)(de)知識范圍內,還可以(yi)在不脫(tuo)離本(ben)發明(ming)宗旨(zhi)的(de)(de)前提下作出各種變化。