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============================================喜歡這套資料就充值下載吧。。。資源目錄里展示的都可在線預(yù)覽哦。。。下載后都有,,請(qǐng)放心下載,,文件全都包含在內(nèi),,【有疑問(wèn)咨詢QQ:1304139763或 1064457796】
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凸輪軸支撐軸頸車床夾具
4.1 車床夾具設(shè)計(jì)要求說(shuō)明
車床夾具主要用于車削凸輪軸支撐軸頸夾具。因而車床夾具的主要特點(diǎn)是工件加工表面的中心線與機(jī)床主軸的回轉(zhuǎn)軸線同軸。
(1) 安裝在車床主軸上的夾具。這類夾具很多,有通用的三爪卡盤、四爪卡盤,花盤,頂尖等,還有自行設(shè)計(jì)的心軸;專用夾具通??煞譃樾妮S式、夾頭式、卡盤式、角鐵式和花盤式。這類夾具的特點(diǎn)是加工時(shí)隨機(jī)床主軸一起旋轉(zhuǎn),刀具做進(jìn)給運(yùn)動(dòng)
定心式車床夾具 在定心式車床夾具上,工件常以孔或外圓定位,夾具采用定心夾緊機(jī)構(gòu)。
角鐵式車床夾具 在車床上加工殼體、支座、杠桿、接頭等零件的回轉(zhuǎn)端面時(shí),由于零件形狀較復(fù)雜,難以裝夾在通用卡盤上,因而須設(shè)計(jì)專用夾具。這種夾具的夾具體呈角鐵狀,故稱其為角鐵式車床夾具。
花盤式車床夾具 這類夾具的夾具體稱花盤,上面開(kāi)有若干個(gè)T形槽,安裝定位元件、夾緊元件和分度元件等輔助元件,可加工形狀復(fù)雜工件的外圓和內(nèi)孔。這類夾具不對(duì)稱,要注意平衡。
(2) 安裝在托板上的夾具。某些重型、畸形工件,常常將夾具安裝在托板上。刀具則安裝在車床主軸上做旋轉(zhuǎn)運(yùn)動(dòng),夾具做進(jìn)給運(yùn)動(dòng)。
由于后一類夾具應(yīng)用很少,屬于機(jī)床改裝范疇。而生產(chǎn)中需自行設(shè)計(jì)的較多是安裝在車床主軸上的專用夾具,所以零件在車床上加工用專用夾具。
4.2車床夾具的設(shè)計(jì)要點(diǎn)
(1)定位裝置的設(shè)計(jì)特點(diǎn)和夾緊裝置的設(shè)計(jì)要求
當(dāng)加工回轉(zhuǎn)表面時(shí),要求工件加工面的軸線與機(jī)床主軸軸線重合,夾具上定位裝置的結(jié)構(gòu)和布置必須保證這一點(diǎn)。
當(dāng)加工的表面與工序基準(zhǔn)之間有尺寸聯(lián)系或相互位置精度要求時(shí),則應(yīng)以?shī)A具的回轉(zhuǎn)軸線為基準(zhǔn)來(lái)確定定位元件的位置。
工件的夾緊應(yīng)可靠。由于加工時(shí)工件和夾具一起隨主軸高速回轉(zhuǎn),故在加工過(guò)程中工件除受切削力矩的作用外,整個(gè)夾具還要受到重力和離心力的作用,轉(zhuǎn)速越高離心力越大,這些力不僅降低夾緊力,同時(shí)會(huì)使主軸振動(dòng)。因此,夾緊機(jī)構(gòu)必須具有足夠的夾緊力,自鎖性能好,以防止工件在加工過(guò)程中移動(dòng)或發(fā)生事故。對(duì)于角鐵式夾具,夾緊力的施力方式要注意防止引起夾具變形。
(2)夾具與機(jī)床主軸的連接
車床夾具與機(jī)床主軸的連接精度對(duì)夾具的加工精度有一定的影響。因此,要求夾具的回轉(zhuǎn)軸線與臥式車床主軸軸線應(yīng)具有盡可能小的同軸度誤差。
心軸類車床夾具以莫氏錐柄與機(jī)床主軸錐孔配合連接,用螺桿拉緊。有的心軸則以中心孔與車床前、后頂尖安裝使用。
根據(jù)徑向尺寸的大小,其它專用夾具在機(jī)床主軸上的安裝連接一般有兩種方式:
1)對(duì)于徑向尺寸D<140mm,或D<(2~3)d的小型夾具,一般用錐柄安裝在車床主軸的錐孔中,并用螺桿拉緊,如圖1-a所示。這種連接方式定心精度較高。
2)對(duì)于徑向尺寸較大的夾具,一般用過(guò)渡盤與車床主軸軸頸連接。過(guò)渡盤與主軸配合處的形狀取決于主軸前端的結(jié)構(gòu)。
圖1-b所示的過(guò)渡盤,其上有一個(gè)定位圓孔按H7/h6或H7/js6與主軸軸頸相配合,并用螺紋和主軸連接。為防止停車和倒車時(shí)因慣性作用使兩者松開(kāi),可用壓板將過(guò)渡盤壓在主軸上。專用夾具則以其定位止口按H7/h6或H7/js6裝配在過(guò)渡盤的凸緣上,用螺釘緊固。這種連接方式的定心精度受配合間隙的影響。為了提高定心精度,可按找正圓校正夾具與機(jī)床主軸的同軸度。
對(duì)于車床主軸前端為圓錐體并有凸緣的結(jié)構(gòu),如圖1-c所示,過(guò)渡盤在其長(zhǎng)錐面上配合定心,用活套在主軸上的螺母鎖緊,由鍵傳遞扭矩。這種安裝方式的定心精度較高,但端面要求緊貼,制造上較困難。
圖1-d所示是以主軸前端短錐面與過(guò)渡盤連接的方式。過(guò)渡盤推入主軸后,其端面與主軸端面只允許有0.05~0.1mm的間隙,用螺釘均勻擰緊后,即可保證端面與錐面全部接觸,以使定心準(zhǔn)確、剛度好。
圖1 車床夾具與機(jī)床主軸的連接
過(guò)渡盤常作為車床附件備用,設(shè)計(jì)夾具時(shí)應(yīng)按過(guò)渡盤凸緣確定專用夾具體的止口尺寸。過(guò)渡盤的材料通常為鑄鐵。各種車床主軸前端的結(jié)構(gòu)尺寸,可查閱有關(guān)手冊(cè)
4.3 定位機(jī)構(gòu)
1.采用兩中心孔定位裝夾
一般以重要的外圓面作為粗基準(zhǔn)定位,加工出中心孔,再以軸兩端的中心孔為定位精基準(zhǔn);盡可能做到基準(zhǔn)統(tǒng)一、基準(zhǔn)重合、互為基準(zhǔn),并實(shí)現(xiàn)一次安裝加工多個(gè)表面。中心孔是工件加工統(tǒng)一的定位基準(zhǔn)和檢驗(yàn)基準(zhǔn),它自身質(zhì)量非常重要,其準(zhǔn)備工作也相對(duì)復(fù)雜,常常以支承軸頸定位,車(鉆)中心錐孔;再以中心孔定位,精車外圓;以外圓定位,粗磨錐孔;以中心孔定位,精磨外圓;最后以支承軸頸外圓定位,精磨(刮研或研磨)錐孔,使錐孔的各項(xiàng)精度達(dá)到要求。
2.用外圓表面定位裝夾
對(duì)于空心軸或短小軸等不可能用中心孔定位的情況,可用軸的外圓面定位、夾緊并傳遞扭矩。一般采用三爪卡盤、四爪卡盤等通用夾具,或各種高精度的自動(dòng)定心專用夾具,如液性塑料薄壁定心夾具、膜片卡盤等。
3.用各種堵頭或拉桿心軸定位裝夾
加工空心軸的外圓表面時(shí),常用帶中心孔的各種堵頭或拉桿心軸來(lái)安裝工件。小錐孔時(shí)常用堵頭;大錐孔時(shí)常用帶堵頭的拉桿心軸。
4.4夾緊機(jī)構(gòu)
選擇工件的夾緊方案,夾緊方案的選擇原則是夾得穩(wěn),夾得勞,夾得快。選擇夾緊機(jī)構(gòu)時(shí),要合理確定夾緊力的三要素:大小、方向、作用點(diǎn)。夾緊裝置的基本要求如下:
1. 夾緊時(shí)不能破壞工件在夾具中占有的正確位置;
2. 夾緊力要適當(dāng),既要保證工件在加工過(guò)程中不移動(dòng)、不轉(zhuǎn)動(dòng)、不震動(dòng),又不因夾緊力過(guò)大而使工件表面損傷、變形。
3. 夾緊機(jī)構(gòu)的操作應(yīng)安全、方便、迅速、省力。
4. 機(jī)構(gòu)應(yīng)盡量簡(jiǎn)單,制造、維修要方便。
分析零件加工要素的性質(zhì),確定夾緊動(dòng)力源類型為手動(dòng)夾緊,夾緊裝置為壓板,壓緊力來(lái)源為螺旋力。夾具的具體結(jié)構(gòu)與參數(shù)見(jiàn)夾具裝配圖和零件圖。
根據(jù)工件受力切削力、夾緊力的作用情況,找出在加工過(guò)程中對(duì)夾緊最不利的瞬間狀態(tài),按靜力平衡原理計(jì)算出理論夾緊力。最后為保證夾緊可靠,再乘以安全系數(shù)作為實(shí)際所需夾緊力的數(shù)值。即:
安全系數(shù)K可按下式計(jì)算有::
式中:為各種因素的安全系數(shù),查參考文獻(xiàn)[5]表可得:
所以有:
螺旋夾緊時(shí)產(chǎn)生的夾緊力按以下公式計(jì)算有:
式中參數(shù)由參考文獻(xiàn)[5]可查得:
其中:
螺旋夾緊力:
由計(jì)算可知所需實(shí)際夾緊力不是很大,為了使其夾具結(jié)構(gòu)簡(jiǎn)單、操作方便,決定選用手動(dòng)螺旋夾緊機(jī)構(gòu)。
4.5零件的車床夾具的加工誤差分析
工件在車床夾具上加工時(shí),加工誤差的大小受工件在夾具上的定位誤差、夾具誤差、夾具在主軸上的安裝誤差和加工方法誤差的影響。
如夾具圖所示,在夾具上加工時(shí),尺寸的加工誤差的影響因素如下所述:
(1)定位誤差
由于C面既是工序基準(zhǔn),又是定位基準(zhǔn),基準(zhǔn)不重合誤差為零。工件在夾具上定位時(shí),定位基準(zhǔn)與限位基準(zhǔn)是重合的,基準(zhǔn)位移誤差為零。因此,尺寸的定位誤差等于零。
(2)夾具誤差
夾具誤差為限位基面與軸線間的距離誤差,以及限位基面相對(duì)安裝基面的平行度誤差是0.01.
(3)安裝誤差
因?yàn)閵A具和主軸是莫氏錐度配合,夾具的安裝誤差幾乎可以忽略不計(jì)。
(4)加工方法誤差
如車床主軸上安裝夾具基準(zhǔn)與主軸回轉(zhuǎn)軸線間的誤差、主軸的徑向跳動(dòng)、車床溜板進(jìn)給方向與主軸軸線的平行度或垂直度等。它的大小取決于機(jī)床的制造精度、夾具的懸伸長(zhǎng)度和離心力的大小等因素。一般取
因?yàn)楣ぜ亩ㄎ换鶞?zhǔn)和定位元件均有制造誤差,所以工件在夾具中定位后的實(shí)際位置將在一定范圍內(nèi)變動(dòng),即存在一定的定位誤差,設(shè)計(jì)定位裝置時(shí),就要控制這一誤差在加工中所允許的范圍內(nèi)。
產(chǎn)生定位誤差的原因有以下兩個(gè)方面:1)定位基準(zhǔn)和工序基準(zhǔn)不重合;2)定位基準(zhǔn)位移。定位誤差就是由基準(zhǔn)不重合誤差和基準(zhǔn)位移公差綜合引起的同批工件工序尺寸的那部分公差,也就是等于兩者的代數(shù)和。
(3-6)
本夾具的主要定位元件為固定塊,軸向定位時(shí)定位基準(zhǔn)——右?jiàn)A具體的左端面與止推面的接合面即為軸頸工序基準(zhǔn),即不存在基準(zhǔn)位移公差也不存在基準(zhǔn)不重合誤差,所以。
當(dāng)主軸頸直徑存在誤差時(shí),定位基準(zhǔn)A或B沿固定塊工作面的位移為
(3-7)
所以基準(zhǔn)不重合誤差為
(3-8)
基準(zhǔn)位移誤差為
(3-9)
則總的定位誤差為
(3-10)
已知本工序中,,故
(3-11)
4.6 確定夾具體結(jié)構(gòu)尺寸和總體結(jié)構(gòu)
夾具體設(shè)計(jì)的基本要求
(1)應(yīng)有適當(dāng)?shù)木群统叽绶€(wěn)定性
夾具體上的重要表面,如安裝定位元件的表面、安裝對(duì)刀塊或?qū)蛟谋砻嬉约皧A具體的安裝基面,應(yīng)有適當(dāng)?shù)某叽缇群托螤罹?,它們之間應(yīng)有適當(dāng)?shù)奈恢镁取?
為使夾具體的尺寸保持穩(wěn)定,鑄造夾具體要進(jìn)行時(shí)效處理,焊接和鍛造夾具體要進(jìn)行退火處理。
(2)應(yīng)有足夠的強(qiáng)度和剛度
為了保證在加工過(guò)程中不因夾緊力、切削力等外力的作用而產(chǎn)生不允許的變形和振動(dòng),夾具體應(yīng)有足夠的壁厚,剛性不足處可適當(dāng)增設(shè)加強(qiáng)筋。
(3)應(yīng)有良好的結(jié)構(gòu)工藝性和使用性
夾具體一般外形尺寸較大,結(jié)構(gòu)比較復(fù)雜,而且各表面間的相互位置精度要求高,因此應(yīng)特別注意其結(jié)構(gòu)工藝性,應(yīng)做到裝卸工件方便,夾具維修方便。在滿足剛度和強(qiáng)度的前提下,應(yīng)盡量能減輕重量,縮小體積,力求簡(jiǎn)單。
(4)應(yīng)便于排除切屑
在機(jī)械加工過(guò)程中,切屑會(huì)不斷地積聚在夾具體周圍,如不及時(shí)排除,切削熱量的積聚會(huì)破壞夾具的定位精度,切屑的拋甩可能纏繞定位元件,也會(huì)破壞定位精度,甚至發(fā)生安全事故。因此,對(duì)于加工過(guò)程中切屑產(chǎn)生不多的情況,可適當(dāng)加大定位元件工作表面與夾具體之間的距離以增大容屑空間:對(duì)于加工過(guò)程中切削產(chǎn)生較多的情況,一般應(yīng)在夾具體上設(shè)置排屑槽。
(5)在機(jī)床上的安裝應(yīng)穩(wěn)定可靠
夾具在機(jī)床上的安裝都是通過(guò)夾具體上的安裝基面與機(jī)床上的相應(yīng)表面的接觸或配合實(shí)現(xiàn)的。當(dāng)夾具在機(jī)床工作臺(tái)上安裝時(shí),夾具的重心應(yīng)盡量低,支承面積應(yīng)足夠大,安裝基面應(yīng)有較高的配合精度,保證安裝穩(wěn)定可靠。夾具底部一般應(yīng)中空,大型夾具還應(yīng)設(shè)置吊環(huán)或起重孔。
確定夾具體的結(jié)構(gòu)尺寸,然后繪制夾具總圖。詳見(jiàn)繪制的夾具裝配圖。
4.7 零件的車床專用夾具簡(jiǎn)單使用說(shuō)明
(1)夾具的總體結(jié)構(gòu)應(yīng)力力求緊湊、輕便,懸臂尺寸要短,重心盡可能靠近主軸。
(2)當(dāng)工件和夾具上個(gè)元件相對(duì)機(jī)床主軸的旋轉(zhuǎn)軸線不平衡時(shí),將產(chǎn)生較大的離心力和振動(dòng),影響工件的加工質(zhì)量、刀具的壽命、機(jī)床的精度和安全生產(chǎn),特別是在轉(zhuǎn)速較高的情況下影響更大。因此,對(duì)于重量不對(duì)稱的夾具,要有平衡要求。平衡的方法有兩種:設(shè)置平衡塊或加工減重孔。在工廠實(shí)際生產(chǎn)中,常用適配的方法進(jìn)行夾具的平衡工作。
(3)為了保證安全,夾具上各種元件一般不超過(guò)夾具的圓形輪廓之外。因此,還應(yīng)該注意防止切削和冷卻液的飛濺問(wèn)題,必要時(shí)應(yīng)該加防護(hù)罩。
將左右?jiàn)A具體固定在頭架和尾架中的主軸上,然后把定位銷(4個(gè))打入夾具體,再把左右兩固定塊固定到各自的夾具體上。用百分表調(diào)整第1或第6軸頸軸心線,使其處于車床主軸回轉(zhuǎn)中心位置,然后夾緊凸輪軸,再將套在凸輪軸皮帶輪軸頸上
畢業(yè)設(shè)計(jì)(論文)撰寫規(guī)范
畢業(yè)論文(設(shè)計(jì)說(shuō)明書(shū)、創(chuàng)作說(shuō)明書(shū))是學(xué)生在教師的指導(dǎo)下經(jīng)過(guò)調(diào)查研究、科學(xué)實(shí)驗(yàn)或工程設(shè)計(jì),對(duì)所取得成果的科學(xué)表述,是學(xué)生畢業(yè)及學(xué)位資格認(rèn)定的重要依據(jù)。其撰寫在參照國(guó)家、各專業(yè)部門制定的有關(guān)標(biāo)準(zhǔn)及語(yǔ)法規(guī)范的同時(shí),應(yīng)遵照如下規(guī)范:
1.?論文結(jié)構(gòu)及寫作要求
論文應(yīng)包括題目、中文摘要與關(guān)鍵詞、英文題目、英文摘要與關(guān)鍵詞、目錄、正文、致謝、參考文獻(xiàn)和附錄等部分。
1.1?題目
題目應(yīng)該簡(jiǎn)短、明確、有概括性。論文題目一般中文題目不超過(guò)25個(gè)字,外文題目不超過(guò)15個(gè)實(shí)詞,不使用標(biāo)點(diǎn)符號(hào),中外文題名應(yīng)一致。標(biāo)題中盡量不用英文縮寫詞,必須采用時(shí),應(yīng)使用本行業(yè)通用縮寫詞。
1.2?摘要與關(guān)鍵詞
1.2.1?摘要
摘要是對(duì)論文內(nèi)容不加注釋和評(píng)論的簡(jiǎn)短陳述,要求扼要說(shuō)明研究工作的目的、主要材料和方法、研究結(jié)果、結(jié)論、科學(xué)意義或應(yīng)用價(jià)值等,是一篇具有獨(dú)立性和完整性的短文。摘要中不宜使用公式、圖表以及非公知公用的符號(hào)和術(shù)語(yǔ),不標(biāo)注引用文獻(xiàn)編號(hào)。中文摘要一般為300字左右,外文摘要為250個(gè)實(shí)詞左右,外文摘要應(yīng)與中文摘要內(nèi)容一致。
1.2.2?關(guān)鍵詞
關(guān)鍵詞是供檢索用的主題詞條,應(yīng)采用能覆蓋論文主要內(nèi)容的通用技術(shù)詞條(參照相應(yīng)的技術(shù)術(shù)語(yǔ)標(biāo)準(zhǔn)),一般列3~5個(gè),按詞條的外延層次從大到小排列,應(yīng)在摘要中出現(xiàn)。
1.3?目錄
目錄獨(dú)立成頁(yè),包括論文中全部章、節(jié)的標(biāo)題及頁(yè)碼。目錄中的標(biāo)題應(yīng)與正文中的標(biāo)題一致,附錄也應(yīng)依次列入目錄。
1.4?論文正文
論文正文包括緒論、論文主體及結(jié)論等部分。
1.4.1?緒論
緒論應(yīng)綜合評(píng)述前人工作,說(shuō)明論文工作的選題目的、背景和意義、國(guó)內(nèi)外文獻(xiàn)綜述以及論文所要研究的主要內(nèi)容。對(duì)所研究問(wèn)題的認(rèn)識(shí),以及提出問(wèn)題。
1.4.2?論文主體
論文主體是論文的主要部分,應(yīng)該結(jié)構(gòu)合理,層次清楚,重點(diǎn)突出,文字簡(jiǎn)練、通順。
1.4.3?結(jié)論(結(jié)果與分析)
結(jié)論是對(duì)整個(gè)論文主要成果的歸納,應(yīng)突出論文(設(shè)計(jì))的創(chuàng)新點(diǎn),以簡(jiǎn)練的文字對(duì)論文的主要工作進(jìn)行評(píng)價(jià)。若不可能導(dǎo)出應(yīng)有的結(jié)論,則進(jìn)行必要的討論??梢栽诮Y(jié)論或討論中提出建議、研究設(shè)想及尚待解決的問(wèn)題等等。
1.5?致謝
向給予指導(dǎo)、合作、支持及協(xié)助完成研究工作的單位、組織或個(gè)人致謝,內(nèi)容應(yīng)簡(jiǎn)潔明了、實(shí)事求是,避免俗套。
1.6?參考文獻(xiàn)
參考文獻(xiàn)反映論文的取材來(lái)源、材料的廣博程度。論文中引用的文獻(xiàn)應(yīng)以近期發(fā)表的與論文工作直接有關(guān)的學(xué)術(shù)期刊類文獻(xiàn)為主。應(yīng)是作者親自閱讀或引用過(guò)的,不應(yīng)轉(zhuǎn)錄他人文后的文獻(xiàn)。
1.7?附錄
不宜放在正文中但有重要參考價(jià)值的內(nèi)容(如公式的推導(dǎo)、程序流程圖、圖紙、數(shù)據(jù)表格等)可編入論文的附錄中。
2.?書(shū)寫及打印要求
2.1?論文書(shū)寫
論文要求統(tǒng)一使用Microsoft?Word軟件進(jìn)行文字處理,統(tǒng)一采用A4頁(yè)面(210×297㎜)復(fù)印紙打印。其中上邊距25㎜、下邊距25㎜、左邊距25㎜、右邊距25㎜、頁(yè)眉15㎜、頁(yè)腳15㎜。論文各章(包括致謝、參考文獻(xiàn)和附錄等)應(yīng)另起一頁(yè),正文為宋體五號(hào),字間距為標(biāo)準(zhǔn),行間距為1.5倍行距。頁(yè)眉內(nèi)容統(tǒng)一為“成都學(xué)院(成都大學(xué))學(xué)士學(xué)位論文(設(shè)計(jì))”,采用宋體小五號(hào)斜體字居右排寫。
頁(yè)碼在下邊線下居中放置,Times?New?Roman小五號(hào)字體。摘要、關(guān)鍵詞、目錄等文前部分的頁(yè)碼用羅馬數(shù)字(Ⅰ、Ⅱ……)編排,正文以后的頁(yè)碼用阿拉伯?dāng)?shù)字(1、2……)編排。
2.2?標(biāo)題
題目使用小二號(hào)黑體,居中。
2.3?摘要與關(guān)鍵詞
中、外文摘要與關(guān)鍵詞單獨(dú)成頁(yè)置于目錄前,編排上中文在前,外文在后。摘要、關(guān)鍵詞題頭均用五號(hào)黑體字,內(nèi)容用五號(hào)宋體。關(guān)鍵詞各詞條間用分號(hào)“;”隔開(kāi)。
2.4?目錄
目錄應(yīng)包括論文中全部章節(jié)的標(biāo)題及頁(yè)碼,含正文章、節(jié)題目、致謝、參考文獻(xiàn)、附錄等。目錄編排最多使用三級(jí)目錄(即:1……、1.1……、1.1.1……),二、三級(jí)目錄相對(duì)前級(jí)目錄右縮進(jìn)一個(gè)漢字位置,要求標(biāo)題層次清晰。
目錄題頭用四號(hào)黑體字居中排寫,隔行書(shū)寫目錄內(nèi)容。
2.5?論文正文
2.5.1?章節(jié)及各章標(biāo)題
章節(jié)標(biāo)題應(yīng)突出重點(diǎn)、簡(jiǎn)明扼要,字?jǐn)?shù)一般在15字以內(nèi),不使用標(biāo)點(diǎn)符號(hào)。標(biāo)題中盡量不采用英文縮寫詞,對(duì)必須采用者,應(yīng)使用本行業(yè)的通用縮寫詞。
2.5.2?層次
層次根據(jù)實(shí)際需要選擇,以少為宜。各層次標(biāo)題不得置于頁(yè)面的最后一行(孤行)。層次代號(hào)格式要求參照表2-1和表2-2。
表2-1??理工科類論文層次代號(hào)及說(shuō)明
章
緒論(章標(biāo)題可省略)
居中,四號(hào)黑體
第1章□×××××
居中,四號(hào)黑體
節(jié)
□□1.1□×××××
空兩格,小四號(hào)黑體
條
□□1.1.1□×××××
空兩格,五號(hào)黑體
款
□□1.1.1.1□×××××
空兩格,五號(hào)黑體
□□×××××××××××××××××××××××××××××××
首行空兩格,五號(hào)宋體
項(xiàng)
□□(1)××××
首行空兩格,五號(hào)宋體
□□×××××××××××××××××××××××××××××××
首行空兩格,五號(hào)宋體
表2-2?文管經(jīng)法類論文層次代號(hào)及說(shuō)明
章
緒論(章標(biāo)題可省略)
居中,四號(hào)黑體
第一章□×××××
居中,四號(hào)黑體
節(jié)
□□(一)××××
空兩格,小四號(hào)黑體
條
□□1.×××××
空兩格,五號(hào)宋體
□□×××××××××××××××××××××××××××××××
空兩格,五號(hào)宋體(正文)
款
□□(1)××××
空兩格,五號(hào)宋體
□□×××××××××××××××××××××××××××××××
空兩格,五號(hào)宋體(正文)
項(xiàng)
□□①×××××
首行空兩格,五號(hào)宋體
□□×××××××××××××××××××××××××××××××
首行空兩格,五號(hào)宋體(正文)
2.6?參考文獻(xiàn)
2.6.1?文獻(xiàn)標(biāo)識(shí)
論文正文中須標(biāo)識(shí)參考文獻(xiàn)編號(hào),按出現(xiàn)順序用小五號(hào)字體標(biāo)識(shí),置于所引內(nèi)容最末句的右上角(上標(biāo))。文獻(xiàn)編號(hào)用阿拉伯?dāng)?shù)字置于方括號(hào)“[?]”中,如:×××××[1];×××××[4,5];×××××[6-8]。當(dāng)提及的參考文獻(xiàn)為文中直接說(shuō)明時(shí),其序號(hào)應(yīng)該與正文排齊,如“由文獻(xiàn)[8,10~14]可知……”。
論文中引用文獻(xiàn)原文應(yīng)加引號(hào);若引用原意,文前用冒號(hào)或逗號(hào),不用引號(hào)。較完整的長(zhǎng)段引文應(yīng)提行獨(dú)立成段,即在冒號(hào)后另起一段。為區(qū)別正文,書(shū)寫時(shí)整體縮進(jìn)兩格(首行相對(duì)正文縮進(jìn)四格),采用楷體小五號(hào)字書(shū)寫,引文頭尾處不必再加引號(hào)。
2.6.2?書(shū)寫格式
參考文獻(xiàn)題頭用黑體四號(hào)字居中排寫。其后空一行寫文獻(xiàn)條目。
參考文獻(xiàn)書(shū)寫格式應(yīng)按論文引用順序編排,文獻(xiàn)編號(hào)頂格書(shū)寫,加括號(hào)“[?]”,其后空一格寫作者名等內(nèi)容。文字換行時(shí)與作者名第一個(gè)字對(duì)齊。常用參考文獻(xiàn)編寫規(guī)定如下:
著作圖書(shū)類文獻(xiàn)——[序號(hào)]□作者.書(shū)名.版次.出版者,出版年:引用部分起止頁(yè)
翻譯圖書(shū)類文獻(xiàn)——[序號(hào)]□作者.書(shū)名.譯者.版次.出版者,出版年:引用部分起止頁(yè)
學(xué)術(shù)刊物類文獻(xiàn)——[序號(hào)]□作者.文章名.學(xué)術(shù)刊物名.年,卷(期):引用部分起止頁(yè)
學(xué)術(shù)會(huì)議類文獻(xiàn)——[序號(hào)]□作者.文章名.編者名.會(huì)議名稱,會(huì)議地址,年份.出版地,出版者,出版年:引用部分起止頁(yè)
學(xué)位論文類文獻(xiàn)——[序號(hào)]□學(xué)生姓名.學(xué)位論文題目.學(xué)校及學(xué)位論文級(jí)別.答辯年份:引用部分起止頁(yè)
其中:文獻(xiàn)作者為多人時(shí),一般只列出3名作者,不同作者姓名間用逗號(hào)相隔。外文姓名按國(guó)際慣例,將作者名的縮寫置前,作者姓置后;學(xué)術(shù)刊物文獻(xiàn)無(wú)卷號(hào)的可略去此項(xiàng),直接寫“年,(期)”。????
2.7?公式
原則上居中書(shū)寫。若公式前有文字(如“解”、“假定”等),文字頂格書(shū)寫,公式仍居中寫。公式末不加標(biāo)點(diǎn)。公式序號(hào)按章編排,并在公式后靠頁(yè)面右邊線標(biāo)注,如第1章第一個(gè)公式序號(hào)為“(1-1)”,附錄2中的第一個(gè)公式為“(②-1)”等。文中引用公式時(shí),一般用“見(jiàn)式(1-1)”或“由公式(1-1)”。
公式較長(zhǎng)時(shí)在等號(hào)“=”或運(yùn)算符號(hào)“+、-、×、÷”處轉(zhuǎn)行,轉(zhuǎn)行時(shí)運(yùn)算符號(hào)書(shū)寫于轉(zhuǎn)行式前,不重復(fù)書(shū)寫。公式中應(yīng)注意分?jǐn)?shù)線的長(zhǎng)短(主、副分線嚴(yán)格區(qū)分),長(zhǎng)分線與等號(hào)對(duì)齊。
公式中第一次出現(xiàn)的物理量應(yīng)給予注釋,注釋的轉(zhuǎn)行應(yīng)與破折號(hào)“——”后第一個(gè)字對(duì)齊,格式見(jiàn)下例:
式中??Mf——試樣斷裂前的最大扭矩(N·m);
Θf——試樣斷裂時(shí)的單位長(zhǎng)度上的相對(duì)扭轉(zhuǎn)角
2.8?插表
表格一般采取三線制,不加左、右邊線,上、下底為粗實(shí)線(1磅),中間為細(xì)實(shí)線(0.75磅)。比較復(fù)雜的表格,可適當(dāng)增加橫線和豎線。
表序按章編排,如第1章第一個(gè)插表序號(hào)為“表1-1”等。表序與表名之間空一格,表名不允許使用標(biāo)點(diǎn)符號(hào)。表序與表名置于表上,居中排寫,采用黑體小五號(hào)字。
表頭設(shè)計(jì)應(yīng)簡(jiǎn)單明了,盡量不用斜線。表頭中可采用化學(xué)符號(hào)或物理量符號(hào)。全表如用同一單位,將單位符號(hào)移到表頭右上角,加圓括號(hào)。表中數(shù)據(jù)應(yīng)正確無(wú)誤,書(shū)寫清楚。數(shù)字空缺的格內(nèi)加“—”字線(占2個(gè)數(shù)字寬度)。表內(nèi)文字和數(shù)字上、下或左、右相同時(shí),不允許用“″”、“同上”之類的寫法,可采用通欄處理方式。
文法經(jīng)管類論文,插表在表下一般根據(jù)需要可增列補(bǔ)充材料、注解、資料來(lái)源、某些指標(biāo)的計(jì)算方法等。補(bǔ)充材料中中文文字用楷體小五號(hào)字,外文及數(shù)字用Times?New?Roman體小五號(hào)字。
2.9?插圖
插圖應(yīng)符合國(guó)家標(biāo)準(zhǔn)及專業(yè)標(biāo)準(zhǔn),與文字緊密配合,文圖相符,技術(shù)內(nèi)容正確。
2.9.1?圖題及圖中說(shuō)明
圖題由圖號(hào)和圖名組成。圖號(hào)按章編排,如第1章第一圖圖號(hào)為“圖1-1”等。圖題置于圖下,圖注或其他說(shuō)明時(shí)應(yīng)置于圖與圖題之間。圖名在圖號(hào)之后空一格排寫,圖題用黑體小五號(hào)字。引用圖應(yīng)說(shuō)明出處,在圖題右上角加引用文獻(xiàn)編號(hào)。圖中若有分圖時(shí),分圖號(hào)用A)、B)標(biāo)識(shí)并置于分圖之下。圖中各部分說(shuō)明應(yīng)采用中文(引用的外文圖除外)或數(shù)字項(xiàng)號(hào),各項(xiàng)文字說(shuō)明置于圖題之上(有分圖題者,置于分圖題之上),采用揩體小五號(hào)字。
2.9.2?插圖編排
插圖與其圖題為一個(gè)整體,不得拆開(kāi)排寫于兩頁(yè)。插圖應(yīng)編排在正文提及之后,插圖處的該頁(yè)空白不夠時(shí),則可將其后文字部分提前排寫,將圖移到次頁(yè)最前面。
2.9.3?照片圖
論文中照片圖均應(yīng)是原版照片粘貼,不得采用復(fù)印方式。照片應(yīng)主題突出、層次分明、清晰整潔、反差適中。對(duì)顯微組織類照片必須注明放大倍數(shù)。
2.10?附錄
附錄序號(hào)采用“附錄1”、“附錄2”或“附錄一”、“附錄二”等,用四號(hào)黑體字居中排寫,其后不加標(biāo)點(diǎn)符號(hào),空一行書(shū)寫附錄內(nèi)容。附錄內(nèi)容文字字體字號(hào)參照正文要求。
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附錄1??摘要及關(guān)鍵詞示例
題目(小二號(hào)黑體)
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摘要(五號(hào)黑體):××××××。(內(nèi)容五號(hào)宋體,200-300字)
關(guān)鍵詞(五號(hào)黑體):×××;×××;×××(內(nèi)容五號(hào)宋體,3-5個(gè)實(shí)詞)
(空一行)
Title(小二號(hào)Time?New?Roman)
(空一行)
Abstract(五號(hào)黑體):××××××。(五號(hào)Times?New?Roman,200—300個(gè)實(shí)詞)
Key?Words(五號(hào)黑體):?×××;×××;××××(五號(hào)Times?New?Roman,3-5個(gè)實(shí)詞,)
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附錄2??目錄示例
目□錄
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緒論…………………………………………………………………………………………………1
第1章□…………………………………………………………………………………………3
1.1□…………………………………………………………………………………………3
1.2□…………………………………………………………………………………………3
1.2.1□…………………………………………………………………………………3
1.2.2□…………………………………………………………………………………4
第2章□…?………………………………………………………………………………………5
2.1□…………………………………………………………………………………………5
2.1.1□…………………………………………………………………………………5
2.1.2□…………………………………………………………………………………9
2.2□…………………………………………………………………………………………11
第3章□…………………………………………………………………………………………13
3.1□…………………………………………………………………………………………13
3.2□…………………………………………………………………………………………15
3.2.1□…………………………………………………………………………………15
3.2.2□…………………………………………………………………………………17
第4章□結(jié)論……………………………………………………………………………………18
致謝………………………………………………………………………………………………19
參考文獻(xiàn)…………………………………………………………………………………………20
附錄………………………………………………………………………………………………21
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附錄3??參考文獻(xiàn)示例
參考文獻(xiàn)
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[1]□J.?R.?McDonnell,?D.?Wagen.?Evolving?Recurrent?Perceptions?For?Time-Series?Modeling.?IEEE?Trans.?On?Neural?Networks.?1994,?5(1):?24—38
[2]□X.?Yao.?Evolutionary?Artifitial?Neural?Networks.?J.?Of??Neural?Systems.?1933,(4):?203-222
[3]□S.?Niwa,?M.?Suzuki?And?K.?Kimura.?Electrical?Shock?Absorber?For?Docking?System?In?Space.?IEEE?International?Workshop?On?Intelligent?Motion?Control,?Bogazici?University,?Istenbul.?1990:?825—830
[4]□林來(lái)興.空間控制技術(shù).宇航出版社,1992:25—42
[5]□吳葳,洪炳熔.自由浮游空間機(jī)器人捕捉目標(biāo)的運(yùn)動(dòng)規(guī)劃研究.中國(guó)第五屆機(jī)器人學(xué)術(shù)會(huì)議論文集.哈爾濱,1997:75—80
[6]□諶穎.空間最優(yōu)交會(huì)控制理論與方法研究.哈爾濱工業(yè)大學(xué)博士論文.?1992:8—13
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Mechanical Parts Processing Technology and Fixture Design Pick to : the machining parts of the structure and process analysis, identified the machine- finishing craft route, fixture in the mechanical processing of the status and importance, as well as the fixture design. With the increasingly development of scientific progress and the adjustment of national industry policy, project machinery industry already became no policy barriers of perfectly competitive industry Key words: technical background / development / process / positioning scheme 1 Mechanical Processing Historical Background and Its Significance Machinery manufacturing industry is an old and eternal industry full of vitality. With the development of modern industry, the mechanical product of the increasingly high demand, machinery manufacturing technology are developing rapidly. Since the founding of new China, our countrys manufacturing technology and manufacturing industry to obtain the considerable development, a considerable size and technical basis of mechanical industry system is formed basically. Years of reform and opening up, Chinas manufacturing industry to make full use of domestic and foreign two aspects of technological resources, there are plans to promote the technical transformation of enterprises, guide enterprises to take the road to rely on progress of science and technology, manufacturing technology, product quality and level and the economic benefit produced marked change, in order to promote the development of the national economy has made great contribution. Although our country manufacturing industry comprehensive technical level has been greatly improved, but compared with developed country, still have level sex difference. Enter the twenty-first Century, the economic development of our country s leading industry still is the manufacturing industry, especially after our country joins WTO, the worlds manufacturing center is developed from migration to Asia, China has cheap labor and the general consumer market, accordingly, industry of our country wants to develop, need to have appropriate technology and equipment support. Machinery industry is the equipment industry of national economy; it is content of science and technology of foundation; is new and high technology industrialization; is the basis of national defense building; is to achieve rapid economic growth of the important pillar; is to improve peoples living quality, provide consumer electrical products supply industry. It runs to national economy, the quality and efficiency of industrial structure adjustment and optimization is a very important role. 2 The Status of Machinery Industry and Development Trend With the development of society, all kinds of machinery and gradually applied to the various industry, whether in the agricultural, military, industrial, mechanical operation, leaving no efficiency, therefore, in some sense, the strength of a countrys economy, social status, and the development of machinery industry is close separable. The industrialized countries economic development course indicated that, without a strong equipment manufacturing industry, is impossible to achieve national economy industrialization, modernization and information 3 . At present, the equipment manufacturing industry development lag is restricting Chinas economic development and industrial upgrading of the important factors, increase structural adjustment strength, promote mechanical industry lasts, healthy, steady development, to change the mode of economic growth, improve quality of national economy whole, enhance the international competitiveness of the economy, security and national defense security has important and far-reaching meaning of. 3 Of Machining Process Planning 3.1 Machining Process Definition The machining process is the use of mechanical processing method of change in rough shape, size, the relative position and the nature, make its become finished or semi-finished products of the whole process. Machining process directly determines the parts and the quality and performance of products, product cost, production period has great influence, is an important part of the whole process. 3.2 Mechanical Processes The composition of mechanical machining process of the basic unit is a process. Process and is formed by mounting, station, working steps and take the knife. The process is a group of workers, in a work of the same or simultaneously on several workpieces are completed for that part of the process. Process is the formulation of labor quota, with workers and machine tool equipment, arranging operation plan and quality testing of the basic unit. The installation is a workpiece by a fixture after the completion of the procedures. The application of switch ( or displacement) when processing machine tool ( or fixture ) processing, in a fixture, the workpiece ( or cutter ) relative to the machine tool passes through several locations in order processing, in each position is done on that part of the process, called station. The multi-station processing can reduce the times of clamping, reduce the mounting error, improve productivity. The step is processing the surface in the cutting tool and the cutting parameters ( only refers to the spindle speed and feed rate ) are the same circumstances completed part of the process. 3.3 Machining Process Definition Products or components manufacturing process and operation methods of the process, called process, it is the enterprise in the production of technical guidance document. 3.4 Machining Process Planning Function and Content Machining process is ready for production work mainly on the basis of. According to its raw material and semifinished product supply, machine tool adjustment, special process equipment design and manufacturing, production scheduling, allocation of labor force, and the production cost accounting. The machining process planning and organization of production, planning and scheduling based on. It can make production schedule and the corresponding scheduling, and can be connected to the scientific process, production is balanced, smooth, to realize high quality, high yield and low consumption. Machining process card and machining process card, are the two main process documents. Machining process card, is illustrated parts machining process technology files. In a single, small batch production, to machining process card guiding production, process card various projects in the preparation of more detailed. Machining process card for each process detailed formulation, used to direct workers, used for mass production parts and mass production of the important parts in the. 3.5 Making The Machining Process Planning Principles and Steps Under certain production conditions, with minimal consumption of labor and the lowest cost, according to plans processing parts that meet requirements of the drawings, is to develop the basic principle of machining process. Formulation of machining process steps are as follows: The under parts of the production program decision production type; The analysis of parts processing technology; The choice of blank type and manufacturing method; The technological process; The process design; The process documentation. 4 Fixture Design 4.1 Fixture Design Sense In the machinery industry, how to guarantee the high precision of workpiece, the costs of processing and other substantive issues, has been engaged in the mechanical industry research questions, which in the design of fixture when we should consider the problems above, efficient fixture is the workpiece precision guarantee, how to make the fixture more efficient, more economical, the industry is the urgent need to resolve. With the development of society, the continuous improvement of technology, various high- tech technology gradually infiltrated into all sectors, how to use these high-tech to serve mankind, how to make full use of the technology in mechanical industry, it also requires machinery industry staff continued efforts, innovation. With the development of science and technology, and social needs of the market, the fixture design in progressive super to the flexible manufacturing system development. To date, the fixture is mechanical and electrical products manufacturing in the four indispensable tools, tool itself is already highly standardized, the user only needs to press varieties, specifications selection and procurement. While the mold and fixture and related products products, there is a need to make changes, usually belong to the special properties of the tool, mould has become an independent industry; fixture at home and abroad is also gradually form a dependent or independent small industry of machine tool industry. Combined clamp not only has the standardization, modularization, modular and other contemporary advanced design ideas, and in line with resource conservation principle, more suitable for green manufacturing environment protection principle. So the next fixture technology is an important direction of development unit. Machine tool fixture is usually refers to the use of clamping workpiece clamping device: for the device with various tools, also known as tool. The auxiliary tool is sometimes generalized to include in the range of machine tool fixture. According to the application range of machine tool fixture, generally can be divided into general jig, fixture and adjustable fixture. Universal jig is on general machine tools are generally accompanied by a common fixture, such as a lathe chuck, milling machine rotary table, dividing head, top seat. They have a standardized, with certain universality, can be used to install certain shape and size within the range of the workpiece without the need for special adjustment. However, in actual production, a universal fixture often can not meet the needs of various parts processing; or because of low productivity and must have the universal fixture for proper improvement; or because the shape of the workpiece, the processing requirements to be different specialized design and manufacture of a special jig, in order to solve the actual production needs. Jig is adapted to a workpiece in a processing requirements and the design and manufacturing expertise, its function mainly has the following several aspects: 1 ensure that the surface of the workpiece being processed mainly includes processing workpieces need maneuvering time of loading and unloading workpieces need the auxiliary time of two part. 2 using a dedicated fixture, workpiece installation and conversion work work can be greatly simplified, no longer need to draw the line and to find it, to shorten the working procedure non-cutting time and save line drawing this process, thereby improving the labor productivity. In production due to the adoption of multiple parallel processing workpiece fixture, enabling the simultaneous processing several parts of the motor will time and processing time of the same motor. The rotary multi-station continuous processing fixture, can be used for machining a workpiece at the same time, other workpiece loading and unloading, thereby enabling the auxiliary time and motor time coincides. In short, with the special fixture using and further improvement, can effectively shorten the process time, production to meet the evolving needs of. 3 using a dedicated fixture can expand the scope of machine tool technology. For example in lathe boring jig attached, can replace boring work; special fixture can be installed after turning the molding surface, so as to give full play to the role of general machine tools. 4, reduce the labor intensity, and ensuring safety production. According to the demand of production, using pneumatic, hydraulic or other mechanical changes, a higher degree of automation of the special fixture, to reduce the labor intensity of workers, protection of production safety and the stability of product quality and high yield of a great role. Processing large workpieces, such as the lathe bed, the lower surfaces of the screw holes on the bed, need to flip several times for processing workpieces, high labor intensity and safety. The use of electric rotary drill furniture, can improve production efficiency, reduce labor intensity, ensure safety in production. 4.2 Fixture of The Development Trend Industrial design is the development of human society and the progress of science and technology of the product, from Maurices the arts and Crafts Movement, to the German Bauhaus design revolution and the United States of America wide dissemination and promotion, industrial design after brewing, exploration, formation, development history of more than 100 years of vicissitudes. Today, industrial design has become an independent subject, and a complete set of research system. In 1980 the International Council of societies of industrial design ( ICSID ) to the industry as a clearly defined: production of industrial products, by training, technical knowledge, experience and visual experience, and indicates the material, structure, morphology, structure, color, surface processing, decoration to the new quality and specification, called industrial design. According to the specific circumstances of the time, industrial designer in the industry products are all side or a few aspects of the work, but also the need for industrial designers of packaging, publicity, display, market development and other issues to resolve pay their own technical knowledge and experience and ability of the visual evaluation, which also belongs to the scope of industrial design. Material, structure, technology is the product design material and technical basis, on one hand, technology restrict the design; on the other hand, technology is also promoting design. From the point of view of design aesthetics, technology is not only the material basis but also has its own function action, as long as good application properties of the materials, to the corresponding structure and suitable processing technology, can create a practical, aesthetic, economic products, namely in the product technology potential function. Any design are the product of the times, its different features, different features reflect the different historical periods of level of science and technology. Technology is the product of the morphological development of the pilot, new material, new technology products, is bound to bring new structure, new forms and new style. Materials, processing technology, structure, product image organic ground is contacted together, a part of the change, it will cause the whole body changes. Now, the machining process and fixture with the development of manufacturing technology also make a spurt of progress. Machining process to the various factories in different circumstances, its processing procedures are very different. Break through the past death mode. Make it with different cases has more reasonable technological process. So that product quality greatly improved. Develop processing technology can be rational, but also to meet the basic requirements: guarantee product quality under the premise, as far as possible to improve labor productivity and reduce the processing cost. And to make full use of the existing factory production conditions, as far as possible, using domestic and foreign advanced technology and experience. Should also ensure that the good working conditions. But our country present stage still rely mainly on technology personnel experience to prepare process, often does not require step and cutting amount, man-hour quota is to be determined by experience, very rough, the lack of scientific basis, difficult to carry out reasonable economic accounting International Journal of production Research Association statistics show that, at present, small batch production of many varieties of workpiece varieties accounted for about 85% of the total number of the kind of workpiece. Modern manufacturing requirements of enterprises manufacturing products constantly upgrading, to meet the needs of the market and competition. However, the general enterprises are still accustomed to the traditional special fixture, generally in the medium having a production capacity of the plant, some have thousands or even nearly 10000 sets of special fixture; on the other hand, in the production of many varieties of the company, every 3 to 4 years to update 50 80% special jig, fixture actual wear only 10 20% or so. Especially in recent years, CNC machine tools, machining center, group technology, flexible manufacturing system ( FMS ), a new processing technology of machine tool fixture, proposed the following new requirements: 1) can rapidly and conveniently and equipment of new products put into production, so as to shorten the production cycle, reduce the production cost; 2) capable of clamping a group with similar characteristics of the workpiece; 3) can be applied to precision machining of high precision machine tool fixture; 4) can be applied to all the modern manufacturing technology of new machine tool fixture; 5) adopts the hydraulic station for power efficient clamping device, in order to further reduce the labor intensity and improve labor productivity; 6) improve the standardization degree of machine tool fixture. The development trend of modern machine tool fixture mainly for standardization, efficiency, precision and flexibility in four aspects. Use better fixture, can improve labor productivity, improve processing accuracy, reduce waste, machine tool technology can expand the scope, improve the operation of labor conditions. Therefore, the fixture machinery manufacturing is an important process equipment. A good fixture is the processing of qualified products of the first condition, in order to allow the clamp has the better development, fixture industry should strengthen the production, learning and research, collaborative efforts, accelerate the use of high technology to transform and upgrade the level of technology to create the pace of jig, fixture professional technology website, make full use of modern information and network technology, and when in keeping with the innovation and development of fixture technology. Active and foreign fixture manufacturer, for joint venture and cooperation, the introduction of technology, it is the reform and development of our country industry is more effective ways of fixture.