【正文】
Plastic deformation stages: punching power reached its peak. Features section features stage In the first stage of sheet metal punch under pressure. First of all produce flexible pression, tensile, such as deformation, then punch a little squeeze into the sheet metal, sheet metal on the other side has a slight edge squeeze into the die, the punch Below the Department of slightly bending the material, die on the edge of the above material began Shangqiao, the greater the gap, bending and Shangqiao more serious, in the convex sheet metal, die cutting edge angle formed the initial collapse, then the internal material Stress has not been more than elastic limit, when the external force can be removed after the material restitution. This phase known as the elastic deformation stage. Elastic deformation stages: punching power gradually increased. 3 fracture separation stages: to punch down, the pressure increased, microcrack growth. Coincidence, fracture, blanking of gradually declining. 2 plastic deformation stages: Punch increasing downward pressure on, until a change in plastic microcracks. 1 elastic deformation stages: Gang Jiechu sheet metal punch the initial stage, in elastic deformation. 5, pound die: punching in the shape of the mutual position of high accuracy, suitable for mass production.Punching the material properties of materials First, when punching materials separation process can be divided into three stages: 4, Die: of the material requirements of precise positioning, and shape each other in the hole location accuracy is assured. High productivity, has a punching accuracy, suitable for mass production. 3, I. Column: I. blanking spaceoriented guarantee uniform, blanking of the workpiece size highprecision molds long life, easy installation, suitable for mass production. 2, I. Plate: accuracy than the openhigh, suitable for simple beginning, not the size of the workpiece blanking pieces. Request not more than press tour guide plate thickness. 1, open mode: simple structure, small size, light weight, easy to manufacture, low cost, but low life expectancy, poor accuracy, suitable for precision Yaoqiubugao, the beginning of simple, lowvolume or blanking of the trial production. s how it works, directly or asked to die on the fixed on the position of the mold on the module, it handles through the mode of association with the press slider. Fixed on the next module is posed of the dieunder, and use clips fixed at the press table. Onandunder through I. I. oriented. Work, of the material sent to rely on positioning block material, when the module with the slider down, unloading first壓住sheet, and then convexconcave with access to the material above the workpiece. At this time the workpiece in the punch card and heard the top of the block, waste is also firmly behind the punch on. In the pickup mode, the workpiece by block through the roof top of the stretch from spring to die from the hole in the roof at the same time behind the punch on the waste discharge by the board on the elastic Xiediao spring, and then took part, this Blanking plete the whole process. Of the material sent to a further step, the next blanking blanking process, so a reciprocating. Second, the classification Die 再一次非常感謝的領(lǐng)導(dǎo),老師以及與我一起討論的各位同學(xué)對(duì)我的關(guān)心和幫助,我才能夠完成我的畢業(yè)設(shè)計(jì)。老師深邃的學(xué)科洞察力、淵博的學(xué)識(shí)、平易近人的作風(fēng)、嚴(yán)謹(jǐn)求實(shí)的態(tài)度、創(chuàng)造性的學(xué)術(shù)意識(shí)、崇高的道德修養(yǎng)、兢兢業(yè)業(yè)的敬業(yè)作風(fēng)、一絲不茍的科學(xué)精神和對(duì)學(xué)生啟發(fā)式和全面型的培養(yǎng)方式,都給我留下了終生難忘的印象,在潛移默化中培養(yǎng)了我不斷奮發(fā)向上、刻苦鉆研的精神和真誠(chéng)待人接物的優(yōu)良品質(zhì),并將最終使我受益終生。同時(shí),特別感謝導(dǎo)師老師。在這兩年里有老師的無(wú)私指導(dǎo)以及同學(xué)的熱心關(guān)懷,我學(xué)到了很多的東西。本設(shè)計(jì)在宋若峰老師的關(guān)心,指導(dǎo)下完成,在此,本人再次真誠(chéng)的對(duì)宋老師及其它一切關(guān)心支持我們?cè)O(shè)計(jì)工作的老師和同學(xué)們表示衷心地感謝!致 謝 在基礎(chǔ)課以及專(zhuān)業(yè)課的學(xué)習(xí)中,讓我感受到了學(xué)習(xí)是無(wú)止境的和知識(shí)的重要性。此次設(shè)計(jì)也是對(duì)我發(fā)現(xiàn),分析,解決問(wèn)題能力的一次極好的鍛練。通過(guò)本設(shè)計(jì),對(duì)模具的結(jié)構(gòu)和設(shè)計(jì)思路有了更深入的理解,熟悉了沖壓模具加工的優(yōu)點(diǎn),特點(diǎn),并且對(duì)大學(xué)四年所學(xué)過(guò)的課程進(jìn)行了一次總復(fù)習(xí),總運(yùn)用。繼續(xù)放入板料開(kāi)始下一個(gè)工作循環(huán)。 。同時(shí)凸模將凸凹模內(nèi)的輪輻成品件推下。如圖46所示圖4 6 模具總裝配圖1—長(zhǎng)螺釘,2—螺釘M1676,3—橡膠,4—導(dǎo)套,5—卸料板,6—凸模,7—凹模,8—導(dǎo)柱,9—模柄,10—上模座,11—上墊板,12—凹模固定板,13—下墊板,14—推料桿,15—工件,16—墊環(huán),17—凸模固定板,18—下模板第五章 模具的工作過(guò)程凹模在最高點(diǎn)時(shí)此時(shí)放入板料。在設(shè)計(jì)中螺釘固定的凹槽大小深度案螺釘直徑大小家1mm確定。將其安裝在凸凹模的沖孔凹模內(nèi),最上面與下壓板板接觸,兩個(gè)壓板之間安裝著橡膠,托板依靠橡膠向上的彈力將頂桿向下頂出,從而完成下料的過(guò)程。F=(50/2)3=2)確定橡膠壓縮量和工作行程橡膠允許最大壓縮量應(yīng)不超過(guò)自由高度h的45%,否則會(huì)過(guò)早失去彈性而損壞,一般總壓縮量?。篽=()h=()60=21~27 mm (49) 取h=23mm橡膠的預(yù)壓縮量h一般取自由高度h的10%15%,即:h=()h=()60 =6~9mm (410) 取h=7mm故橡膠工作行程: L = h h= () h =14~21 mm(411)取L=18mm查表的橡膠的個(gè)數(shù)選擇為6個(gè),在凹模上平均分布。由《冷沖模國(guó)家標(biāo)準(zhǔn)》中查得橡膠的直徑和高度為5060,聚氨脂橡膠的總壓縮量一般35%,對(duì)于沖裁模,其壓縮量一般取10%15%。冷沖模中的橡膠一般為聚氨脂橡膠(PUR)。圖45 模柄結(jié)構(gòu)圖1—模柄,2—凹模固定板,3—上壓板壓入式模柄。熱處理:硬度62~66HRC。導(dǎo)柱與導(dǎo)套的結(jié)構(gòu)配合如圖44所示圖44 導(dǎo)套導(dǎo)柱裝配結(jié)構(gòu)圖B型導(dǎo)套。導(dǎo)柱與導(dǎo)套之間的配合根據(jù)沖裁模的間隙大小選用,~4 mm時(shí),選用H7/h6配合的Ⅱ級(jí)精度模架。在選用時(shí)應(yīng)注意導(dǎo)柱的長(zhǎng)度應(yīng)沖模在最低工作位置時(shí),導(dǎo)柱上端面必須低于上模座平面(一般不小于10~15 mm),并保證有足夠的導(dǎo)向長(zhǎng)度。熱處理:~,硬度:52~68HRC。 導(dǎo)柱的結(jié)構(gòu)尺寸見(jiàn)圖43圖43 導(dǎo)柱B型導(dǎo)柱。在選用時(shí)應(yīng)注意導(dǎo)柱的長(zhǎng)度應(yīng)沖模在最低工作位置時(shí),導(dǎo)柱上端面必須低于上模座平面(一般不小于10~15 mm),并保證有足夠的導(dǎo)向長(zhǎng)度。導(dǎo)柱導(dǎo)套的間隙值應(yīng)小于沖模中凸模、凹模間隙,導(dǎo)柱裝置有以下幾種情況:導(dǎo)柱設(shè)計(jì)在底座上,為常用形式,裝配調(diào)整較為方便;導(dǎo)柱設(shè)計(jì)在上模板上,有利于彈性卸料板導(dǎo)向的安裝;臺(tái)階式導(dǎo)柱,大端直徑等于導(dǎo)套的外徑,這樣便于上、下模板一起加工,并能保證導(dǎo)向的同軸度;在一些要求彈性卸料板有良好導(dǎo)向的情況下,導(dǎo)柱有時(shí)也兼作卸料板的導(dǎo)向裝置。導(dǎo)向裝置設(shè)計(jì)的注意事項(xiàng):1)導(dǎo)柱與導(dǎo)套應(yīng)在凸模工作前或壓料板接觸到工件前充分閉合,且此時(shí)應(yīng)在保證導(dǎo)柱上端距上模座上平面留有間隙10~15mm的間隙;2)導(dǎo)柱、導(dǎo)套與上、下模板裝配后,應(yīng)保證導(dǎo)柱與下模座的下平面、導(dǎo)套上端與上模座的上平面均留有2~3mm的間隙;3)對(duì)于形狀對(duì)稱(chēng)的工件,為避免合模安裝時(shí)引起的方向錯(cuò)誤,兩側(cè)導(dǎo)柱直徑或位置應(yīng)有所不同;4)當(dāng)沖模有較大的側(cè)向壓力時(shí),模座上應(yīng)裝設(shè)止推墊,避免導(dǎo)套、導(dǎo)柱承受側(cè)向力;5)導(dǎo)套應(yīng)開(kāi)排氣孔以排除空氣。 導(dǎo)向裝置導(dǎo)向裝置可提高模具精度、壽命及工件的質(zhì)量,而且還能節(jié)省調(diào)試模具的時(shí)間。四角導(dǎo)柱式模架主要用與精度要求高的沖壓件和大型沖壓件。沖壓模具的閉合高度應(yīng)大于壓力機(jī)的最小裝模高度,小于壓力機(jī)的最大裝模高度等。模板的厚度一般應(yīng)該等于凹模厚度的1~。選擇模架結(jié)構(gòu)時(shí)要根據(jù)工件的受力特點(diǎn),坯件定位,出件方式,材料送進(jìn)方向,導(dǎo)柱受力狀態(tài),操作是否方便進(jìn)行綜合考慮。根據(jù)模架導(dǎo)向用的導(dǎo)柱和導(dǎo)套間的配合性質(zhì)分為滑動(dòng)導(dǎo)向模架和滾動(dòng)導(dǎo)向模架兩大類(lèi)。沖壓模具的全部零件都安裝在模架上。定位銷(xiāo)的直徑設(shè)為20mm,數(shù)量同樣為6個(gè),在以模具的對(duì)稱(chēng)中心為中心平均分布。定位精度要求較高時(shí),要考慮粗定位和精定位兩套裝置,分步進(jìn)行;坯件需要兩個(gè)以上工序的定位時(shí),它們的定位基準(zhǔn)應(yīng)該一致;設(shè)計(jì)定位裝置還應(yīng)考慮避免坯件正、反誤放置的措施。定位零件是確定條料或坯料在模具中的正確位置的零件。凹模刃口要鋒利,強(qiáng)度要大,表面粗糙度要?。ㄒ话銥镽a=~),外輪廓棱角要倒鈍。由于凹模受力復(fù)雜,很難按理論方法精確計(jì)算,對(duì)于非標(biāo)準(zhǔn)尺寸的凹模一般不作強(qiáng)度核算,可用公式或查表確定其尺寸。為了提高模具壽命與沖裁件精度,凹模的底面和型孔的孔壁應(yīng)光滑,表面粗糙度為Ra=~,底面與銷(xiāo)孔的Ra==~。3. 凹模的固定方法 凹模一般采用螺釘和銷(xiāo)釘固定在下模座上,由于本模具為倒裝式,所以凹模與凸模固定板及墊板用螺釘和銷(xiāo)釘連接在上模座上,銷(xiāo)釘用兩個(gè),以防轉(zhuǎn)動(dòng),用八個(gè)內(nèi)六角螺釘將這幾個(gè)板件固定在上模座上。 2卸料板卸料板的作用主要是在沖壓結(jié)束瞬間,卸料螺釘在橡皮的彈力下將卸料板向上彈起,從而將套在凸模上的剩余條料頂下,因次它的中間是空的,并且空的形狀與沖裁件的外形輪廓相同,安裝時(shí)套在凸凹模