礦用絞車總體設(shè)計(jì)【JH-8型回柱絞車】
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河南理工大學(xué)萬方科技學(xué)院本科畢業(yè)設(shè)計(jì)(論文)中期檢查表指導(dǎo)教師: 職稱: 所在院(系): 教研室(研究室): 題 目礦用絞車總體設(shè)計(jì)學(xué)生姓名專業(yè)班級(jí)0 學(xué)號(hào)一、 選題質(zhì)量:1、 由于各種原因我們學(xué)校機(jī)械專業(yè)有很多科目都是與煤礦、礦山有關(guān)的。因此,我的畢業(yè)設(shè)計(jì)選擇礦用絞車的設(shè)計(jì)可以很好的檢驗(yàn)以前學(xué)過的知識(shí)。通過這次畢業(yè)設(shè)計(jì),從各方面查找的資料也讓我進(jìn)一步了解了礦山設(shè)備的各種情況。2、 這個(gè)設(shè)計(jì)是我和另一位同學(xué)合作完成的他負(fù)責(zé)傳動(dòng)系統(tǒng)的設(shè)計(jì)而我負(fù)責(zé)總體設(shè)計(jì)難度適中既很好地檢驗(yàn)了我們所學(xué)過的知識(shí)也給了我們開拓思維動(dòng)手實(shí)踐的機(jī)會(huì)。主要設(shè)計(jì)任務(wù)是減速器傳動(dòng)裝置和制動(dòng)器的選擇。3、 我們之前在認(rèn)識(shí)實(shí)習(xí)時(shí)在九里山礦看到過絞車但對(duì)它的內(nèi)部結(jié)構(gòu)并不十分了解,通過網(wǎng)上和從圖書館借來的各種資料的幫助下一點(diǎn)點(diǎn)的完善我們的方案達(dá)到設(shè)計(jì)要求。4、 煤炭在我國的能源消費(fèi)結(jié)構(gòu)中占有極大的比重,是工業(yè)發(fā)展的原材料及能源來源,而礦用絞車是煤炭開采的咽喉設(shè)備,它是實(shí)現(xiàn)地面與井下物料、人員交流的重要工具其重要性不言而喻。它的安全性能、工作效率對(duì)生產(chǎn)至關(guān)重要。因此,對(duì)礦用絞車的研究對(duì)生產(chǎn)、經(jīng)濟(jì)、社會(huì)發(fā)展都具有重大意義。二、 開題報(bào)告完成情況:已經(jīng)完成開題報(bào)告并經(jīng)過了老師的批閱三、 階段性成果:1、通過查閱資料掌握了礦用絞車基本的結(jié)構(gòu)、工作原理。2、完成了對(duì)滾筒、大齒輪架的設(shè)計(jì)、繪圖。3、編寫了部分說明書。四、 存在主要問題:1、對(duì)礦用絞車我們并沒有機(jī)會(huì)十分的詳細(xì)的觀察,各種內(nèi)部結(jié)構(gòu)、細(xì)節(jié)很難查找到詳盡的資料。2、很多非主要設(shè)計(jì)結(jié)構(gòu)的尺寸確定需要查找更多的資料。3、對(duì)制動(dòng)器的選擇應(yīng)用需要進(jìn)一步了解、查資料。五、指導(dǎo)教師對(duì)學(xué)生在畢業(yè)實(shí)習(xí)中,勞動(dòng)、學(xué)習(xí)紀(jì)律及畢業(yè)設(shè)計(jì)(論文)進(jìn)展等方面的評(píng)語指導(dǎo)教師: (簽名) 年 月 日3河南理工大學(xué)萬方科技學(xué)院本科畢業(yè)設(shè)計(jì)(論文)開題報(bào)告題目名稱礦用絞車總體設(shè)計(jì)學(xué)生姓名專業(yè)班級(jí)學(xué)號(hào)一、 選題的目的和意義:絞車是工業(yè)生產(chǎn)過程中一種常見的機(jī)械,在礦山采掘和運(yùn)輸場合,絞車作為重要輔助設(shè)備被大量而廣泛地應(yīng)用著是礦山生產(chǎn)中不可缺少的設(shè)備之一。我國絞車發(fā)展歷史大致可分為三個(gè)階段:50年代,仿制設(shè)計(jì)階段,從無到有初步發(fā)展;60年代,自行設(shè)計(jì)階段;70年代以后,標(biāo)準(zhǔn)化,系列化發(fā)展階段,產(chǎn)品初步形成標(biāo)準(zhǔn)化,但是到了現(xiàn)代,我國生產(chǎn)的絞車遠(yuǎn)遠(yuǎn)不能滿足生產(chǎn)能力不同的煤礦的需要。近十年來,國外制造廠家,為適應(yīng)國際市場需要,不斷加大輸送機(jī)的功率、采用新結(jié)構(gòu)、新工藝,開發(fā)高強(qiáng)度、高耐磨性能的新材料,使產(chǎn)品不斷更新,技術(shù)性能日趨完善,可靠性不斷提高,壽命大幅度增加。而我國生產(chǎn)的礦用絞車整機(jī)性能相對(duì)比較差,一些關(guān)鍵零部件的壽命、可靠性相對(duì)較低,監(jiān)測、控制方面相對(duì)比較弱。具體有以下方面。(1)回繩速度慢。絞車在傳動(dòng)系統(tǒng)中設(shè)置了齒輪離合器和錐形摩擦制動(dòng)器,除個(gè)加緊類型絞車可以自由回繩并可以防止鋼絲繩松散外,其余所有絞車回繩速度和工作牽引速度是相同的。因此絞車用于回柱放頂,還是用于搬運(yùn)設(shè)備,工作效率太低。隨著礦山機(jī)械化的發(fā)展,綜采設(shè)備的頻率搬遷,但由于用絞車搬運(yùn),工作時(shí)間長,占用人工多,因此該類絞車應(yīng)設(shè)置快速回繩或自由回繩。(2)牽引速度慢隨著支護(hù)的發(fā)展使用,金屬摩擦支柱、單體液壓支柱后,回柱前可以部分或全部缷載,回柱只是要把它們接到或拖進(jìn)工作面再復(fù)用。同時(shí)絞車也用于搬遷設(shè)備的需要,則其牽引速度應(yīng)從當(dāng)前的5-7m/min左右提高到8-10m/min或再高一點(diǎn)。(3)絞車實(shí)際運(yùn)行質(zhì)量較差,效率偏低。 測試中發(fā)現(xiàn)大多數(shù)絞車均采用手動(dòng)控制,加速、減速及低速爬行和停車休止時(shí)間相對(duì)偏長,使絞車提升能力下降,電機(jī)電耗增加。 近年來,我國各生產(chǎn)廠家對(duì)結(jié)構(gòu)、調(diào)速裝置等進(jìn)行了許多改進(jìn),并推出了許多更新?lián)Q代的產(chǎn)品,隨著計(jì)算機(jī)技術(shù)的飛速發(fā)展,計(jì)算機(jī)和PLC的運(yùn)算速度加快、存貯能力加大、功能加強(qiáng)、體積減小,使煤礦機(jī)械的功能更強(qiáng)、性能更優(yōu)、效率更高。所以這次設(shè)計(jì)有以下目的:1)了解礦用絞車的結(jié)構(gòu)、特點(diǎn)以及工作原理。2)利用學(xué)過的知識(shí)盡可能的實(shí)現(xiàn)設(shè)計(jì)要求3)培養(yǎng)自己的自主設(shè)計(jì)能力、動(dòng)手能力!二、 國內(nèi)外研究綜述:20世紀(jì)末期以來,美、澳、英、德等先進(jìn)采煤國家積極應(yīng)用機(jī)電一體化技術(shù),研制、開發(fā)新型自動(dòng)化運(yùn)輸設(shè)備,這些設(shè)備采用計(jì)算機(jī)工況監(jiān)測監(jiān)控,在增加傳動(dòng)功率,提高生產(chǎn)能力的同時(shí),使設(shè)備的功能內(nèi)涵發(fā)生了重大突破。經(jīng)過十多年的努力,已經(jīng)研制出限矩摩擦離合器作為輸送機(jī)啟動(dòng)或運(yùn)行時(shí)的過載保護(hù),利用調(diào)速偶合器實(shí)現(xiàn)輸送機(jī)的軟啟動(dòng)和過載保護(hù),通過鏈條張力自動(dòng)調(diào)節(jié)裝置來實(shí)現(xiàn)礦用絞車隨運(yùn)行工況的變化以調(diào)節(jié)鏈條的張緊力。通過工況監(jiān)測和故障診斷系統(tǒng),及時(shí)了解設(shè)備運(yùn)行的工況,保證設(shè)備的安全運(yùn)行。國內(nèi)的輕型、中型礦用絞車多采用液力偶合器或雙速電機(jī)來改善絞車的啟動(dòng)性能,重型礦用絞車采用限矩摩擦離合器保護(hù)電機(jī),雖然在個(gè)別輸送機(jī)上使用了調(diào)速偶合器和自動(dòng)伸縮機(jī)尾,可是由于不能準(zhǔn)確的對(duì)輸送機(jī)運(yùn)行過程中的數(shù)據(jù)進(jìn)行采集、分析,這些設(shè)備還不能達(dá)到自動(dòng)控制的要求。三、 畢業(yè)設(shè)計(jì)(論文)所用的主要技術(shù)與方法:此設(shè)計(jì)的傳動(dòng)裝置采用減速器傳動(dòng)雖然當(dāng)今減速器已經(jīng)成為通用的機(jī)械設(shè)備,并已經(jīng)標(biāo)準(zhǔn)化,但是卻沒有一種專門為礦用絞車而設(shè)計(jì)的減速器,所以該設(shè)計(jì)正好填補(bǔ)了這一空白。傳動(dòng)系統(tǒng)放置在滾筒內(nèi)部節(jié)省空間!四、 主要參考文獻(xiàn)與資料獲得情況:1.現(xiàn)代機(jī)械設(shè)備設(shè)計(jì)手冊(cè) . 辛一行主編 機(jī)械工業(yè)出版社 2.機(jī)械設(shè)計(jì)手冊(cè) . 徐 灝主編 機(jī)械工業(yè)出版社 3.減速器和變速器設(shè)計(jì)與選用手冊(cè) 程乃士主編 機(jī)械工業(yè)出版社 4.機(jī)械零件設(shè)計(jì)手冊(cè) 吳宗澤主編 機(jī)械工業(yè)出版社5. 機(jī)械原理 孫桓、陳作模等主編 西北工業(yè)大學(xué)出版社6. 機(jī)械設(shè)計(jì) 濮良貴、紀(jì)名剛主編 高等教育出版社(第八版)7、機(jī)械設(shè)計(jì)工程學(xué) 唐大放,馮小寧,楊現(xiàn)卿主編 中國礦業(yè)大學(xué)出版社8、機(jī)械設(shè)計(jì)基礎(chǔ)課程設(shè)計(jì) 任濟(jì)生等主編 中國礦業(yè)大學(xué)出版社畢業(yè)設(shè)計(jì)(論文)進(jìn)度安排(按周說明):第一周:確定題目第二周:收集相關(guān)資料第三周:確定設(shè)計(jì)方案第四到六周:進(jìn)行結(jié)構(gòu)設(shè)計(jì)第七到八周:進(jìn)行結(jié)構(gòu)設(shè)計(jì)審查第九到十周:繪制設(shè)計(jì)圖紙第十一周:編寫設(shè)計(jì)說明書第十二周:修改完善設(shè)計(jì)說明書第十四至十五周:準(zhǔn)備畢業(yè)答辯五、 指導(dǎo)教師審批意見: 指導(dǎo)教師: (簽名)年 月 日 1 2 前言 .7 1 概論 .8 1.1 絞車的發(fā)展 .8 1.1.1 我國絞車的發(fā)展 .8 1.1.2 國外絞車的發(fā)展 .8 1.1.3 國內(nèi)外水平對(duì)比 .9 1.1.4 總體發(fā)展趨勢 .9 1.1.5“礦用絞車總體設(shè)計(jì) ”設(shè)計(jì)思路 .10 2 絞車的主要技術(shù)參數(shù)的設(shè)計(jì)與計(jì)算 .12 2.1 設(shè)計(jì)的原始參數(shù) .12 2.1.1 電動(dòng)機(jī)的選用 .12 3 總體方案設(shè)計(jì) .14 3.1 設(shè)計(jì)條件 .14 3.2 總體方案的初步擬定 .14 3.3 主要組成部分 .15 4 機(jī)械傳動(dòng)系統(tǒng)方案設(shè)計(jì) .16 4.1 計(jì)算傳動(dòng)裝置總傳動(dòng)比和分級(jí)傳動(dòng)比 .18 4.1.1 傳動(dòng)裝置總傳動(dòng)比 .18 4.1.2 分配各級(jí)傳動(dòng)比 .18 4.2 傳動(dòng)裝置的運(yùn)動(dòng)和動(dòng)力參數(shù) .19 4.2.1 各軸轉(zhuǎn)速 .19 4.2.2 各軸輸入功率 .19 4.2.3 各軸轉(zhuǎn)矩 .19 4.3 高速級(jí)傳動(dòng)件設(shè)計(jì) .20 4.3.1 選擇蝸桿傳動(dòng)類型 .20 4.3.2 選擇材料 .20 4.3.3 蝸輪蝸桿設(shè)計(jì) .20 4.4 低速級(jí)傳動(dòng)件設(shè)計(jì) .24 4.4.1 選擇齒輪類型、精度等級(jí)、材料及齒數(shù) .24 4.4.2 按齒面接觸疲勞強(qiáng)度設(shè)計(jì) .25 4.4.3 計(jì)算 .26 4.4.4 安齒根彎曲強(qiáng)度設(shè)計(jì) .27 4.4.5 設(shè)計(jì)計(jì)算 .28 4.4.6 幾何尺寸計(jì)算 .29 4.7 高速軸設(shè)計(jì)(蝸桿軸) .30 4.7.1 軸的材料選擇 .30 4.7.2 求作用在蝸桿上的力 .30 4.7.3 初步確定軸的最小直徑 .30 4.7.4 軸的校核 .31 3 4.8 中間軸的設(shè)計(jì)(蝸輪齒輪軸) .34 4.8.1 軸的材料選擇 .34 4.8.2 求作用在蝸輪和齒輪上的力 .34 4.8.3 初步估算軸的最小直徑 .34 4.8.4 軸的校核 .35 4.9 低速軸的設(shè)計(jì) .36 4.9.1 軸的材料選擇 .36 4.9.2 求作用在大齒輪上的力 .36 4.9.3 初步確定軸的最小直徑 .36 4.9.4 軸的校核 .37 4.9.5 按彎曲合成應(yīng)力校核軸的強(qiáng)度 .38 4.9.6 按彎曲合成應(yīng)力校核軸的強(qiáng)度 .38 5 主要部件的選型與結(jié)構(gòu)設(shè)計(jì) .40 5.1 制動(dòng)器的選擇 .40 5.1.1 常用絞車制動(dòng)閘的形式 .40 5.1.2 絞車上應(yīng)有的安全裝置 .40 5.1.3 回柱絞車制動(dòng)器的作用 .41 5.1.4 制動(dòng)器的選用和設(shè)計(jì) .42 5.2 滾筒的設(shè)計(jì) .43 5.2.1 滾筒材料 .43 5.2.2 滾筒的功能 .43 5.2.3 滾筒結(jié)構(gòu) .43 5.3 軸承支架的設(shè)計(jì) .44 6 使用與維護(hù) .47 6.1 回柱絞車的操作要求 .47 6.2 開車前必須認(rèn)真檢查 .47 6.3 運(yùn)行中必須注意 .47 6.4 鋼絲繩斷絲原因分析 .48 6.4.1 鋼絲繩間斷斷絲 .48 6.4.2 鋼絲繩連續(xù)斷絲 .48 6.5 絞車的安裝操作 .48 6.6 后移 .49 6.7 維護(hù)與檢修 .50 小結(jié) .51 致 謝 .52 參考文獻(xiàn) .53 4 5 礦用絞車總體設(shè)計(jì) 摘要 回柱絞車又稱慢速絞車,它是能拆除和回收回踩工作面頂柱的一 種機(jī)械。牽引力大和牽引速度慢是回柱絞車的主要性能要求。隨著機(jī)械 化采煤程度的提高,他越來越多的被應(yīng)用于機(jī)械化采煤工作面,作為安 裝、回收牽引各種設(shè)備備件之用。隨著絞的發(fā)展趨勢向標(biāo)準(zhǔn)化系列方向 發(fā)展;向體積小、重量輕、結(jié)構(gòu)緊湊方向發(fā)展;向高效節(jié)能壽命長低噪 音一機(jī)多能通用化大功率外形簡單平滑美觀大方方向展回柱絞車也有了 相應(yīng)的改進(jìn),礦用絞車總體設(shè)計(jì)借鑒 JH-8 回柱絞車和 JT0.86 提升絞 車的參數(shù)結(jié)構(gòu)力求達(dá)到這一目標(biāo)。 關(guān)鍵詞回 回柱絞車 提升絞車 改進(jìn) Abstract Prop-pulling hoist and says slow winch, it is can dismantle and back to back working on a mechanical spots. Traction and slow speed is prop-pulling hoist traction main performance requirements. With the mining mechanization degree rise, more and more be used in mechanized coal face, as installation, recycling of all kinds of equipment and spare parts with traction. Along with the development trend of the ground to the standardized series development direction; To small volume, light weight, compact structure direction; To the high efficiency and energy saving life long low noise, high power universal machine appearance is beautiful and simple smooth direction exhibition prop-pulling hoist also had 6 the corresponding improvement, mine hoist overall design reference JH-8 prop-pulling hoist and JT0.8 x 6 of the parameters of the hoist structure strive to achieve the this goal. Keyword Prop-pulling hoist hoist improvement 7 前言 畢業(yè)設(shè)計(jì)是我們?cè)诖髮W(xué)里的最后一次綜合能力的訓(xùn)練,他讓我們對(duì) 大學(xué)里所學(xué)過的課程譬如機(jī)械零件、機(jī)械原理、材料力學(xué)、礦山機(jī)械機(jī) 械設(shè)計(jì)學(xué)等進(jìn)行離一次全面的了解和加深。四年的大學(xué)生活馬上就要結(jié) 束了,在離開學(xué)校走上工作崗位之前,畢業(yè)設(shè)計(jì)是對(duì)我們的一個(gè)考驗(yàn), 這既考察了我們大學(xué)四年里對(duì)知識(shí)的全面掌握程度,又考察了我們的實(shí) 際應(yīng)用能力以及解決種種困難時(shí)的心態(tài)問題! 在以前的學(xué)習(xí)過程中我們做過了許多次課程設(shè)計(jì),完成過幾份圖紙,但 這次完全使用電腦制圖、完成設(shè)計(jì)對(duì)我們還是第一次。因此,這也鍛煉 了我們對(duì)制圖查資料、電腦制圖的應(yīng)用和熟練程度。為我們?cè)谝院笤诠?作崗位上能夠更加駕輕就熟打下基礎(chǔ),做好鋪墊! 機(jī)械行業(yè)是一個(gè)由許多專業(yè)組成的,技術(shù)性很強(qiáng)的,需要緊密配合 的系統(tǒng)工程。是促進(jìn)我國發(fā)展的生命線。而目前,我國的機(jī)械行業(yè)在世 界之林中還尚處于落后的地位。因此,需要我們把握時(shí)代的的主流,為 國家為社會(huì)做出貢獻(xiàn)! 8 1 概論 1.1 絞車的發(fā)展 1.1.1 我國絞車的發(fā)展 我國的絞車主要經(jīng)歷了仿制、自行設(shè)計(jì)兩個(gè)階段。解放初期使用 的產(chǎn)品主要來自日本與蘇聯(lián),1958 年以后,這些產(chǎn)品相繼被淘汰,并 對(duì)蘇聯(lián)絞車進(jìn)行了改進(jìn),于 1964 年進(jìn)入自行設(shè)計(jì)階段。淮南煤機(jī)廠曾 設(shè)計(jì)了擺線齒輪絞車和少齒差傳動(dòng)絞車,徐州礦山設(shè)備制造廠也曾設(shè)計(jì) 制造了擺線和行星齒輪傳動(dòng)絞車,一些廠家還試制了 25kw 的調(diào)度絞車。 目前,礦用小絞車已經(jīng)在標(biāo)準(zhǔn)化方面得到了相應(yīng)的發(fā)展,于 1982 年, 對(duì)以前指定的標(biāo)準(zhǔn)進(jìn)行了修改。 1.1.2 國外絞車的發(fā)展 國外礦用小絞車使用很普遍,生產(chǎn)廠家也很多。美國、日本、瑞 典等國家都制造了礦用小絞車,而且國外礦用小絞車種類、規(guī)格較多, 比如調(diào)度絞車牽引力以 100kgf 到 3600kgf,動(dòng)力有電動(dòng)的、液力的、 風(fēng)動(dòng)的。工作機(jī)構(gòu)有單筒、雙筒、摩擦式。傳動(dòng)形式有皮帶傳動(dòng)、鏈?zhǔn)?傳動(dòng)、齒輪傳動(dòng)、渦輪傳動(dòng)、液壓傳動(dòng)、行星輪傳動(dòng)、擺線齒輪傳動(dòng)等。 其中采用行星輪傳動(dòng)的比較多。發(fā)展趨勢是向著標(biāo)準(zhǔn)化系列化,向著體 積小、重量輕、結(jié)構(gòu)緊湊方向發(fā)展,向著高效、節(jié)能、壽命長、低噪音、 一機(jī)多能通用化、大功率、外形簡單、平滑、美觀、大方方向發(fā)展的。 9 1.1.3 國內(nèi)外水平對(duì)比 (1)品種 國外礦用絞車的規(guī)格較多,適用于不同場合,我國的礦用絞車 規(guī)格較少品種型號(hào)多,也較繁瑣,標(biāo)準(zhǔn)化程度不夠高。 (2)形式 從工作機(jī)構(gòu)上分,國外有單筒、雙筒、摩擦式,而我國則較少。從 原動(dòng)力上分,國外有電動(dòng)的、風(fēng)動(dòng)的、液壓驅(qū)動(dòng)的。我國只有少量的電 動(dòng)和風(fēng)動(dòng)的。但近幾年有了較大程度的發(fā)展。 (3)結(jié)構(gòu) 我國及國外的調(diào)度絞車大多數(shù)采用行星齒輪傳動(dòng),其傳動(dòng)結(jié)構(gòu)簡 單,使用方便,但牽引力過小,特別是上山、下山很難實(shí)現(xiàn)較大的設(shè)備 搬運(yùn)工作。隨著采煤的機(jī)械化發(fā)展,綜采設(shè)備的頻繁搬遷,絞車也得到 了相應(yīng)的發(fā)展。使得絞車還需要具備快速回繩的功能。 (4)產(chǎn)品性能 主要壽命、噪音、可靠性、等綜合指標(biāo)與國外還有一定差距。 (5)三化水平 雖然我國的礦用絞車參數(shù)系列化方面水平優(yōu)于國外,但標(biāo)準(zhǔn)化和 通用化方面還遠(yuǎn)不如發(fā)達(dá)的機(jī)械制造國。 (6)技術(shù)經(jīng)濟(jì)指標(biāo) 我國的礦用絞車技術(shù)經(jīng)濟(jì)指標(biāo)與國外特別是與美國等機(jī)械發(fā)達(dá)的 國家還有一定差距。 1.1.4 總體發(fā)展趨勢 縱觀國內(nèi)外礦用絞車的發(fā)展情況,其發(fā)展趨勢有以下幾點(diǎn): (1)向著標(biāo)準(zhǔn)化系列化方向發(fā)展 10 使各制造公司都有自己的產(chǎn)品系列型譜,在這些型譜中,對(duì)絞車的 性能、參數(shù)作進(jìn)一步的明確規(guī)定,并強(qiáng)力推行實(shí)施,給設(shè)計(jì)、制造、使 用、維護(hù)帶來極大的方便。 (2)向體積小、重量輕結(jié)、構(gòu)緊湊方向發(fā)展 力求將絞車的運(yùn)動(dòng)及傳動(dòng)裝置、工作滾筒、制動(dòng)裝置部分底座等主 要部件綜合在一個(gè)系統(tǒng)中并加以統(tǒng)籌布局,充分利用空間,提高緊湊程 度,做好外形封閉。 (3)向高效節(jié)能的方向發(fā)展 選取最佳參數(shù),最大限度提高產(chǎn)品功能,采用合理的制造精度, 提高生產(chǎn)效率。向壽命長、低噪音的方向發(fā)展,使綜合性能指標(biāo)得到提 高。 (4)向一機(jī)多能化、通用化方向發(fā)展; (5)向大功率的方向發(fā)展; (6)向外形簡單、平滑、美觀、大方、方向發(fā)展。 1.1.5“礦用絞車總體設(shè)計(jì)”設(shè)計(jì)思路 我所做的畢業(yè)設(shè)計(jì)題目是“礦用絞車總體設(shè)計(jì)” ,根據(jù)實(shí)際情況結(jié) 合網(wǎng)上搜到的資料,借鑒礦用回柱絞車的結(jié)構(gòu)布局和 JT0.80.6 型提 升絞車的滾筒技術(shù)參數(shù)(滾筒直徑為 800mm 寬度為 600mm)進(jìn)行設(shè)計(jì)改 良。回柱絞車的結(jié)構(gòu)有如下特點(diǎn): (1)傳動(dòng)系統(tǒng)都有一級(jí)減速比很大的蝸輪蝸桿傳動(dòng),皆具備自鎖功 能,不會(huì)發(fā)生下故重物拉動(dòng)滾筒旋轉(zhuǎn)情況。 (2)具有整體結(jié)構(gòu),便于移動(dòng)和安裝,甚至可以用回柱絞車牽引力 來牽引絞車本身移動(dòng)。 (3)總傳動(dòng)比大(i150230),能在電動(dòng)機(jī)功率較小時(shí),獲得較大 11 的牽引力。 (4)因蝸輪蝸桿傳動(dòng)效率低,易造成發(fā)熱和溫升過高,所以必須重視 潤滑和維護(hù)。 (5)有的在電動(dòng)機(jī)聯(lián)軸器上裝有手動(dòng)制動(dòng)閘,有的在蝸輪減速器輸 出軸上裝有活動(dòng)齒輪和錐形摩擦制動(dòng)器,使回柱絞車可以按信號(hào)準(zhǔn)確停 位,并能從滾筒上自由放繩(不受蝸桿傳動(dòng)自鎖影響),且可控制放繩速 度,防止松繩和亂繩。 (6)電氣控制裝置較簡單,皆具備隔爆性能,可用于有瓦斯、煤塵 的環(huán)境場所。 12 2 絞車的主要技術(shù)參數(shù)的設(shè)計(jì)與計(jì)算 2.1 設(shè)計(jì)的原始參數(shù) 表 1-1 絞車的主要技術(shù)參數(shù) 滾筒直徑 mm 滾筒個(gè)數(shù) 繩速 m/s 電動(dòng)機(jī)功率 額定轉(zhuǎn)速 r/min 800 1 60 37 1500 2.1.1 電動(dòng)機(jī)的選用 (1)電動(dòng)機(jī)類型和結(jié)構(gòu)型式 回柱絞車主要用于井下回收支柱用,為防止瓦斯、粉塵等有害氣體 引起爆炸,故絞車的電動(dòng)機(jī)需要選用礦用防爆電機(jī).防爆電機(jī)的選型原則 是安全可靠、經(jīng)濟(jì)合理、維護(hù)方便,同其它的防爆電氣設(shè)備一樣應(yīng)根據(jù) 危險(xiǎn)場所的類別和區(qū)域等級(jí)以及在該場所存在的爆炸性混合物的級(jí)別、 組別來選用.在這里我們選用 YB 系列防爆型三相異步電動(dòng)機(jī).結(jié)構(gòu)為封 閉臥式結(jié)構(gòu). (2)傳動(dòng)裝置的總效率 4321A 式中為從電動(dòng)機(jī)到繩筒之間各傳動(dòng)機(jī)構(gòu)和軸承的效率,由表查的滾 13 動(dòng)軸承 0.99,蝸桿傳動(dòng) 0.8,圓柱齒輪傳動(dòng) 0.97,彈性 聯(lián)軸器 0.99,繩筒滑動(dòng)軸承 0.96 則 20.897.0.96.78 (3)電動(dòng)機(jī)額定功率 根據(jù)原始數(shù)據(jù)選取電動(dòng)機(jī)的額定功率 KWPed3 (4)電動(dòng)機(jī)的轉(zhuǎn)速 因?yàn)槭窃诰鹿ぷ?要考慮到其安全可靠性,所以選用防爆電機(jī),即 YB 系列防爆三相異步電機(jī),同步轉(zhuǎn)速為 1500m/min,滿載時(shí)轉(zhuǎn)速為 1480r/min. 14 3 總體方案設(shè)計(jì) 3.1 設(shè)計(jì)條件 (1)機(jī)器用途:煤礦井下回收支柱用的慢速絞車; (2)工作情況:工作穩(wěn)定、平穩(wěn),間歇工作(工作與停歇時(shí)間比為 1:2),繩筒轉(zhuǎn)向定期變換; (3)運(yùn)動(dòng)要求:絞車?yán)K筒轉(zhuǎn)速誤差不超過 8%; (4)工作能力:儲(chǔ)備余量 10%; 3.2 總體方案的初步擬定 根據(jù)設(shè)計(jì)要求,所給原始數(shù)據(jù),經(jīng)過對(duì)回柱絞車常用型號(hào)的傳動(dòng)方 式比較,最后選用一級(jí)為蝸桿傳動(dòng),一級(jí)齒輪傳動(dòng)的傳動(dòng)方式.其傳動(dòng)結(jié) 構(gòu)圖如圖 1-1 所示。該結(jié)構(gòu)簡單,而且占用的空間小,適合井下狹窄空間.第 一級(jí)采用蝸桿機(jī)構(gòu),也符合回柱絞車傳動(dòng)比大的要求,所以經(jīng)過比較,最 終我選擇此種傳動(dòng)方案. 15 圖 1-1 JH-8 回柱絞車的結(jié)構(gòu)簡圖 3.3 主要組成部分 JH-8 型回柱絞車由電動(dòng)機(jī),圓弧面蝸桿蝸輪減速器,卷筒,底盤 五大部分組成。其傳動(dòng)原理是:動(dòng)力由電動(dòng)機(jī)通過一對(duì)聯(lián)軸器傳動(dòng)圓弧 面蝸桿、蝸輪,由蝸輪軸上的小齒輪經(jīng)中間過橋齒輪傳動(dòng)大齒輪,大齒 輪帶動(dòng)卷筒,卷筒引鋼絲繩進(jìn)行工作。這個(gè)設(shè)計(jì)借鑒 JH-8 性回柱絞車 的結(jié)構(gòu)設(shè)計(jì):但取消了過橋齒輪,小齒輪通過與大齒輪嚙合將動(dòng)力傳到 大齒輪,大齒輪所在的軸通過一對(duì)聯(lián)軸器與滾筒相連將動(dòng)力傳到滾筒。 16 4 機(jī)械傳動(dòng)系統(tǒng)方案設(shè)計(jì) 根據(jù)機(jī)械器的工藝性能、結(jié)構(gòu)要求、空間位置和總傳動(dòng)比等條件選 擇機(jī)械傳動(dòng)系統(tǒng)所需的傳動(dòng)類型,并擬定從動(dòng)力機(jī)到工作機(jī)構(gòu)之間機(jī)械 傳動(dòng)系統(tǒng)的設(shè)計(jì)方案和總體布置。 一般情況下,盡管動(dòng)力機(jī)的輸出功率滿足工作機(jī)構(gòu)的要求,但輸出 的轉(zhuǎn)速、扭矩或運(yùn)動(dòng)形式很難符合工作機(jī)構(gòu)的需要,這時(shí)就需要采用某 種機(jī)械傳動(dòng)裝置。這是絕大多數(shù)機(jī)械設(shè)計(jì)的共同特點(diǎn)。 按照傳動(dòng)原理的不同,機(jī)械傳動(dòng)裝置可分為摩擦傳動(dòng)、嚙合傳動(dòng)和 推壓傳動(dòng)三種。根據(jù)傳動(dòng)比能否改變,機(jī)械傳動(dòng)裝置又可分為可調(diào)傳動(dòng) 比傳動(dòng)、固定傳動(dòng)比傳動(dòng)和變傳動(dòng)比傳動(dòng)三類?;刂g車一般采用固定 傳動(dòng)比傳動(dòng)。 減速器傳動(dòng):本回柱絞車由于總減速比較大,而采用動(dòng)力蝸桿減速 器。蝸桿傳動(dòng)的主要特點(diǎn)是:傳動(dòng)比大、結(jié)構(gòu)緊湊、工作平穩(wěn)、無噪聲、 自鎖性能好。對(duì)于回柱絞車,要求卷筒能夠自鎖。即卷筒的正反轉(zhuǎn)只能 由電動(dòng)機(jī)的正反轉(zhuǎn)來控制;當(dāng)電源切斷時(shí)絞車馬上停止工作;卷筒本身 不能自由轉(zhuǎn)動(dòng),以免發(fā)生事故。這就需要設(shè)計(jì)一個(gè)裝置來控制卷筒的自 轉(zhuǎn)。而蝸輪蝸桿傳動(dòng)就起到了這個(gè)作用。因?yàn)槿羧∥仐U的蝸旋線開角 小于齒輪間的當(dāng)量摩擦角 ,則當(dāng)蝸輪主動(dòng)時(shí),機(jī)構(gòu)自鎖,即只能v 蝸桿帶動(dòng)蝸輪,而不能蝸輪帶動(dòng)蝸桿。因此,采用蝸輪蝸桿減速器,就 能保證卷筒的自鎖性。這就是回柱絞車采用蝸桿減速器的一個(gè)重要原因。 但是,采用蝸桿減速器也有一缺點(diǎn),就是傳動(dòng)效率低,這點(diǎn)應(yīng)在具 17 體的蝸桿減速器設(shè)計(jì)中充分重視,并設(shè)法提高。 采用圓弧齒圓柱蝸桿,就是提高效率的一種措施,這是一種新型的 傳動(dòng)裝置。它與普通的蝸桿傳動(dòng)相比,其不同在于,具有良好的潤滑條 件使齒面之間建立連續(xù)的潤滑油膜形成液體摩擦,從而降低摩擦系數(shù), 減輕磨損,提高了承載能力和效率。因此,它具有承載能力大,使用壽 命長,效率高(高 10-15%)等優(yōu)點(diǎn)。 齒輪傳動(dòng):選擇齒輪傳動(dòng),是由于齒輪傳動(dòng)具有工作可靠,使用壽 命長,瞬時(shí)傳動(dòng)比為常數(shù);傳動(dòng)效率高、結(jié)構(gòu)緊湊、功率和速度適用范 圍廣等優(yōu)點(diǎn)。因斜齒輪傳動(dòng)時(shí)會(huì)產(chǎn)生軸向力,對(duì)傳動(dòng)不利。若采用人字 齒輪,雖可使齒輪軸向力自行抵消,但人字齒輪制造比較困難,所以選 擇直齒輪傳動(dòng)。 從結(jié)構(gòu)上看:如果讓蝸輪軸上的齒輪與主軸上的齒輪嚙合,由于傳 動(dòng)比大,會(huì)造成兩齒輪大小相差過甚,大齒輪太大以至于不好安裝和制 造,而且外形尺寸也太大。另外,渦輪軸上的小齒輪也不能太小,因?yàn)?根據(jù)強(qiáng)度要求限制了軸徑,從而控制小齒輪的尺寸只能小到某一程度。 否則,會(huì)給加工成本帶來諸多不便。況且卷筒和大齒輪以及蝸輪尺寸都 較大,讓蝸輪上的齒輪與卷筒上的齒輪直接嚙合,受尺寸限制,不容易 做到?;谝陨显?,決定增加一中間軸,軸上安裝一過橋齒輪。這樣, 既可以得到合適的傳動(dòng)比,又可以令整體布局合理。 現(xiàn)代生產(chǎn)的發(fā)展,無論在承載能力、工作可靠穩(wěn)定方面,還是在結(jié) 構(gòu)尺寸和重量方面,對(duì)齒輪的傳動(dòng)的要求愈來愈高。標(biāo)準(zhǔn)齒輪由于存在 一些缺點(diǎn)限制了它的應(yīng)用范圍。為了滿足設(shè)計(jì)要求,我們決定設(shè)計(jì)三個(gè) 變位齒輪,作為改善齒輪傳動(dòng)質(zhì)量的有效方法。 已知條件:鋼繩牽引力 F=37kN,最大速度 V=60m/min,繩筒直徑 D=800mm,鋼繩直徑 d=14mm ,則滾筒轉(zhuǎn)速為 18 min8.238014.36 6D106n rvw 1 初步擬定出二級(jí)傳動(dòng)的傳動(dòng)方案。因?yàn)槭蔷鹿ぷ鳎嵌喾蹓m,潮濕, 易燃易爆的場合,而且傳遞的功率大,傳動(dòng)要求嚴(yán)格,尺寸要求緊湊, 所以最后選定蝸桿-齒輪二級(jí)減速器。計(jì)算傳動(dòng)裝置總傳動(dòng)比和分級(jí)傳 動(dòng)比 4.1 計(jì)算傳動(dòng)裝置總傳動(dòng)比和分級(jí)傳動(dòng)比 根據(jù)機(jī)械傳動(dòng)系統(tǒng)的設(shè)計(jì)方案把總傳動(dòng)比分配到各級(jí)傳動(dòng)上,并要 求各級(jí)傳動(dòng)結(jié)構(gòu)緊湊,承載能力高,工作可靠,制造經(jīng)濟(jì)和效率高。 4.1.1 傳動(dòng)裝置總傳動(dòng)比 628.23 140i 2 4.1.2 分配各級(jí)傳動(dòng)比 取蝸桿傳動(dòng)比 ,圓柱齒輪傳動(dòng)比36.2i18.2i 19 4.2 傳動(dòng)裝置的運(yùn)動(dòng)和動(dòng)力參數(shù) 4.2.1 各軸轉(zhuǎn)速 高速軸為 1 軸,中間軸為 2 軸,低速軸為 3 軸,則 min4801 rnm 3ir2.63.12i 4 min238.623nri 5 4.2.2 各軸輸入功率 按電動(dòng)機(jī)的額定功率計(jì)算各軸輸入功率,即 kwped371 wk01.298.2212 6 5.7.0.923213 7 20 4.2.3 各軸轉(zhuǎn)矩 mNn75.23814095011pT 8 98.41.60922 9 4.3 高速級(jí)傳動(dòng)件設(shè)計(jì) 4.3.1 選擇蝸桿傳動(dòng)類型 根據(jù) GB/T100851988 的推薦,采用漸開線蝸桿(ZI) 4.3.2 選擇材料 根據(jù)設(shè)計(jì)要求,并考慮到蝸桿傳動(dòng)傳遞的功率不大適中,速度是慢速,故 蝸桿用 20Cr,因需要效率高些,耐磨性好些,故蝸桿螺旋齒面要求淬火, 硬度為 45-55HRC.蝸輪用鑄鋁鐵青銅 ZCuAl10Fe3,金屬模鑄造.為了節(jié)約 貴重的有色金屬,僅齒圈用青銅制造,二輪芯用灰鑄鐵 HT100 鑄造. 4.3.3 蝸輪蝸桿設(shè)計(jì) (1)按齒面接觸疲勞強(qiáng)度進(jìn)行設(shè)計(jì) 根據(jù)閉式蝸桿傳動(dòng)的設(shè)計(jì)準(zhǔn)則,先按齒面接觸疲勞強(qiáng)度設(shè)計(jì),再校核 齒根彎曲疲勞強(qiáng)度. 21 23()EHZaKT 9 (2)確定作用再蝸輪上的轉(zhuǎn)矩 由計(jì)算可知 10mN87.34912.601950T2 (3)確定載荷系數(shù) K 因工作較穩(wěn)定,故取載荷分布不均有系數(shù) ;由表選取使用系K 數(shù) ;由于轉(zhuǎn)速不高 ,沖擊不大,可取動(dòng)載系數(shù) ,1.5AK 1.05V 則 11.0.21 (4)確定彈性影響系數(shù) EZ 因選用得式鑄造鋁鐵青銅蝸輪和鋼蝸桿相配,故 1/260EZMPa (5)確定接觸系數(shù) 先假設(shè)蝸桿分度圓直徑 和傳動(dòng)中心距 a得比值 1/.35d,從中1d 查得 6.2Zp (6)確定許用接觸應(yīng)力 H 根據(jù)蝸輪材料為鑄鋁鐵青銅 ZCuAl10Fe3,金屬模鑄造,蝸桿螺旋齒面 硬度46HRC,可得蝸輪得基本許用應(yīng)力 MPaH260 應(yīng)力循環(huán)次數(shù) 1072 958.102.jNLnh 12 22 壽命系數(shù) 8.095.87HN1K 13 則 MPaHNH2086. 14 (7)計(jì)算中心距 m36.21.10765)28.16(489021.a33 15 取中心距 ,根據(jù)傳動(dòng)比,從手冊(cè)中取模數(shù) ,蝸桿分度5am 8 圓直徑 .這時(shí) ,可得接觸系數(shù) ,因?yàn)?80d1/0.35da51.2ZP ,因此以上計(jì)算結(jié)果可用.Z (8)蝸桿與蝸輪的主要參數(shù)與幾何尺寸 蝸桿 軸向齒距 ;直徑系數(shù) ;齒頂圓直徑 ;齒13.25Pa10qm196adm 根圓直徑 分度圓導(dǎo)程角 ;蝸桿軸向齒厚mf860d1 32.0 .2.5as 蝸輪 蝸輪齒數(shù) ;變位系數(shù) X=-0.5452Z 驗(yàn)算傳動(dòng)比 23 5.24i12z 16 這時(shí)傳動(dòng)比誤差為 這是允許的%63.0.36.2 蝸輪分度圓直徑 17mz04582d 蝸輪喉圓直徑 18mhaa 37682622 蝸輪齒根圓直徑 19dff .5.13722 蝸輪咽喉母圓半徑 20mag 376222r (9)校核齒根彎曲疲勞強(qiáng)度 21.53FFaFKTYd 21 當(dāng)量齒數(shù) 2272.493.054cosz332 v 根據(jù) , ,從中可查得齒形系數(shù)7.2v.x278.2Fa 螺旋角系數(shù) 239.014Y0 24 許用彎曲應(yīng)力 FFNKA 24 從中可得由 ZCuAl10Fe3 制造的蝸輪的基本許用彎曲應(yīng)力MPaF120 壽命系數(shù) 25635.0958.7 6FN1K 所以 , MPaF2.7635.012 26 27MPa8.692.078360.491.1F 彎曲強(qiáng)度是滿足的. (10)驗(yàn)算效率 )tan(96.05.)( 28 已知 , ; 與相對(duì)滑動(dòng)速度 有32.10fvarctnvvs 關(guān)。 25 smnd/32.6cos10648cos106v0s 29 從表中用插值法查得 28.fv.0v 帶人式中得 大于原估計(jì)值,因此不用重算。86.0 (11)精度等級(jí)公差 考慮到所設(shè)計(jì)和表面粗糙度的確定的蝸桿傳動(dòng)是動(dòng)力傳動(dòng),屬于通用 機(jī)械減速器,從 GB/T 10089-1988 圓柱蝸桿,蝸輪精度中選擇 8 級(jí)精度, 側(cè)隙種類為 f,標(biāo)注為 8f GB/T 10089-1988.然后由有關(guān)手冊(cè)查得要求的 公差項(xiàng)目及表面粗糙度,具體見圖紙。 4.4 低速級(jí)傳動(dòng)件設(shè)計(jì) 4.4.1 選擇齒輪類型、精度等級(jí)、材料及齒數(shù) (1)選用直齒圓柱齒輪 (2)絞車為一般工作機(jī)器,速度不高,故選用 7 級(jí)精度(GB10095-88) (3)材料選擇 選擇小齒輪材料為 40Cr(調(diào)質(zhì))硬度為 280HBS,大 齒輪材料為 45 鋼(調(diào)質(zhì))硬度為 240HBS,兩者材料硬度差為 40HBS (4)選小齒輪齒數(shù) ,26z1 則大齒輪齒數(shù) 758.4.2 26 4.4.2 按齒面接觸疲勞強(qiáng)度設(shè)計(jì) 3211.()tEtdHKTZud 1 確定公式內(nèi)的各計(jì)算數(shù)值 (1)試選載荷系數(shù) (初選)1.3tK (2)小齒輪傳遞的轉(zhuǎn)矩 mNNn 418902.60955.922p0T 2 (3)選齒寬系數(shù) 5.0d (4)由此可得的材料的彈性影響因數(shù) 1/289.EZMPa (5)按齒面硬度查得小齒輪接觸疲勞強(qiáng)度極限 ,大齒min60Hl 輪接觸疲勞強(qiáng)度極限 min250HlPa (6)計(jì)算應(yīng)力循環(huán)次數(shù) 181 6.2)538(1.60LNhj 3 08829. (7)可得接觸疲勞壽命系數(shù) , 493.01kHN5.02HN (8)計(jì)算接觸疲勞許用應(yīng)力 27 取失效概率為 1,安全系數(shù) S1 5MPasHNHk586093.lim12in52.lKaS 4.4.3 計(jì)算 (1)試計(jì)算小齒輪分度圓直徑 ,代入 中的較小的值d1t H 6mud ttTk45.275.819(.23148903.2E(.3 21 )Z) (2)計(jì)算圓周速度 7snt /78.0160.160v (3)計(jì)算齒寬 b 8mdt 3.45.27.1 (4)計(jì)算齒寬與齒高 b/h 模數(shù) 9mzdtt 7.82645.1 齒高 10t 6.19.5.h 28 8.56.1973bh 11 (5)計(jì)算載荷系數(shù) K 根據(jù) ,7 級(jí)精度,查圖得動(dòng)載荷系數(shù)s/m29.3v 06.1kv 直齒輪, ;1kFaH 由表 10-2 查得使用系數(shù) ;A 由表用插值法查得 7 級(jí)精度,小齒輪相對(duì)支承非對(duì)稱布置時(shí)38.1F 故動(dòng)載荷系數(shù) 518.432.106.k HvA 12 (6)按實(shí)際的載荷系數(shù)教正所算得的分度圓直徑得 1mkdtt 51.239.8145.27331 3 (7)計(jì)算模數(shù) m mzd2.9651.31 14 29 4.4.4 安齒根彎曲強(qiáng)度設(shè)計(jì) 彎曲強(qiáng)度的設(shè)計(jì)公式為 15321)(mFSadYzTk (1)確定公式內(nèi)的各計(jì)算數(shù)值 由圖查得小齒輪的彎曲疲勞強(qiáng)度極限 ;大齒輪的彎MPa501FE 曲強(qiáng)度極限 ;MPa380FE2 由圖取彎曲疲勞壽命系數(shù) ,86.0k1FN89.FN2 計(jì)算彎曲疲勞許用應(yīng)力 取彎曲疲勞安全系數(shù) S=1.4 則得 MPaaSFENF 14.3074.158601 k5.2.922 計(jì)算載荷系數(shù) K 463.1806.1FavA 查取齒形系數(shù) 由表查得 .2Y1Fa 2.Fa 查取應(yīng)力校正系數(shù) 由表查得 49.1Sa68.12Sa 計(jì)算大小齒輪的 并加以比較aF 30 0126.4.37962Y1SaF 5.82SaF 大齒輪的數(shù)值較大 4.4.5 設(shè)計(jì)計(jì)算 m5.601.48963.12m32 對(duì)此計(jì)算結(jié)果,由齒面接觸疲勞強(qiáng)度計(jì)算的模數(shù) M 大于由齒根彎 曲疲勞強(qiáng)度計(jì)算的模數(shù),由于齒數(shù)模數(shù) M 的大小主要取決于彎曲強(qiáng)度所 決定的承載能力,而齒面接觸疲勞強(qiáng)度所決定的承載能力,僅與齒輪直 徑(即模數(shù)與齒數(shù)的乘積)有關(guān),可取由彎曲強(qiáng)度算得的模數(shù) 6.555 并 就近圓整為標(biāo)準(zhǔn)值 M = 8 mm ,按接觸強(qiáng)度算得的分度圓直徑 ,m51.239d1 算出小齒輪齒數(shù) 304.8.1z 大齒輪的齒數(shù) 取 .6.23087z2 這樣設(shè)計(jì)出的齒輪傳動(dòng),既滿足了齒面接觸疲勞強(qiáng)度,又滿足了 齒根彎曲疲勞強(qiáng)度,并做到結(jié)構(gòu)緊湊,避免浪費(fèi)。 31 4.4.6 幾何尺寸計(jì)算 (1)計(jì)算分度圓直徑 m240831dz m69722 (2)計(jì)算中心距 48a1 (3)計(jì)算齒輪寬度 md1205.0b1 取 mB1202 結(jié)構(gòu)設(shè)計(jì)及繪制齒輪零件圖(見圖紙) 4.7 高速軸設(shè)計(jì)(蝸桿軸) 4.7.1 軸的材料選擇 選用 45 號(hào)鋼,調(diào)質(zhì)。 4.7.2 求作用在蝸桿上的力 已知: , , ,蝸桿分度圓kw37p1min/1480rmN238750T1 直徑 . 所以,80dm 圓周力 1NT75.9680231tF 軸向力 NdTa 89.234041921F 32 徑向力 NadT8463tan36041892tnF02r1 4.7.3 初步確定軸的最小直徑 取 ,于是得01A mnp16.3248071330mind 2 最小直徑處是安裝聯(lián)軸器得直徑 ,為使所選的軸直徑與聯(lián)軸器的1d 孔徑相適應(yīng),故需同時(shí)選聯(lián)軸器的型號(hào). 聯(lián)軸器的計(jì)算轉(zhuǎn)矩 ,查表 14-1,取 ,則0caATK1.3AK mNk 075238.1 3 按照計(jì)算轉(zhuǎn)矩應(yīng)小于聯(lián)軸器公稱轉(zhuǎn)矩的條件,查標(biāo)準(zhǔn) GB/T5014- 1985,選用 TL7 型彈性套柱銷聯(lián)軸器,公稱轉(zhuǎn)矩 ,許用轉(zhuǎn)速50 2800r/min.半聯(lián)軸器孔 徑為 48mLathesLathes are machine tools designed primarily to do turning, facing and boring, Very little turning is done on other types of machine tools, and none can do it with equal facility. Because lathes also can do drilling and reaming, their versatility permits several operations to be done with a single setup of the work piece. Consequently, more lathes of various types are used in manufacturing than any other machine tool.The essential components of a lathe are the bed, headstock assembly, tailstock assembly, and the leads crew and feed rod.The bed is the backbone of a lathe. It usually is made of well normalized or aged gray or nodular cast iron and provides s heavy, rigid frame on which all the other basic components are mounted. Two sets of parallel, longitudinal ways, inner and outer, are contained on the bed, usually on the upper side. Some makers use an inverted V-shape for all four ways, whereas others utilize one inverted V and one flat way in one or both sets, They are precision-machined to assure accuracy of alignment. On most modern lathes the way are surface-hardened to resist wear and abrasion, but precaution should be taken in operating a lathe to assure that the ways are not damaged. Any inaccuracy in them usually means that the accuracy of the entire lathe is destroyed.The headstock is mounted in a foxed position on the inner ways, usually at the left end of the bed. It provides a powered means of rotating the word at various speeds . Essentially, it consists of a hollow spindle, mounted in accurate bearings, and a set of transmission gears-similar to a truck transmissionthrough which the spindle can be rotated at a number of speeds. Most lathes provide from 8 to 18 speeds, usually in a geometric ratio, and on modern lathes all the speeds can be obtained merely by moving from two to four levers. An increasing trend is to provide a continuously variable speed range through electrical or mechanical drives.Because the accuracy of a lathe is greatly dependent on the spindle, it is of heavy construction and mounted in heavy bearings, usually preloaded tapered roller or ball types. The spindle has a hole extending through its length, through which long bar stock can be fed. The size of maximum size of bar stock that can be machined when the material must be fed through spindle.The tailsticd assembly consists, essentially, of three parts. A lower casting fits on the inner ways of the bed and can slide longitudinally thereon, with a means for clamping the entire assembly in any desired location, An upper casting fits on the lower one and can be moved transversely upon it, on some type of keyed ways, to permit aligning the assembly is the tailstock quill. This is a hollow steel cylinder, usually about 51 to 76mm(2to 3 inches) in diameter, that can be moved several inches longitudinally in and out of the upper casting by means of a hand wheel and screw.The size of a lathe is designated by two dimensions. The first is known as the swing. This is the maximum diameter of work that can be rotated on a lathe. It is approximately twice the distance between the line connecting the lathe centers and the nearest point on the ways, The second size dimension is the maximum distance between centers. The swing thus indicates the maximum work piece diameter that can be turned in the lathe, while the distance between centers indicates the maximum length of work piece that can be mounted between centers. Engine lathes are the type most frequently used in manufacturing. They are heavy-duty machine tools with all the components described previously and have power drive for all tool movements except on the compound rest. They commonly range in size from 305 to 610 mm(12 to 24 inches)swing and from 610 to 1219 mm(24 to 48 inches) center distances, but swings up to 1270 mm(50 inches) and center distances up to 3658mm(12 feet) are not uncommon. Most have chip pans and a built-in coolant circulating system. Smaller engine lathes-with swings usually not over 330 mm (13 inches ) also are available in bench type, designed for the bed to be mounted on a bench on a bench or cabinet.Although engine lathes are versatile and very useful, because of the time required for changing and setting tools and for making measurements on the work piece, thy are not suitable for quantity production. Often the actual chip-production tine is less than 30% of the total cycle time. In addition, a skilled machinist is required for all the operations, and such persons are costly and often in short supply. However, much of the operators time is consumed by simple, repetitious adjustments and in watching chips being made. Consequently, to reduce or eliminate the amount of skilled labor that is required, turret lathes, screw machines, and other types of semiautomatic and automatic lathes have been highly developed and are widely used in manufacturing. 2 Numerical ControlOne of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC). Prior to the advent of NC, all machine tools ere manually operated and controlled. Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator. Numerical control represents the first major step away from human control of machine tools. Numerical control means the control of machine tools and other manufacturing systems through the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool. For a machine tool to be numerically controlled, it must be interfaced with a device for accepting and decoding the programmed instructions, known as a reader.Numerical control was developed to overcome the limitation of human operators, and it has done so. Numerical control machines are more accurate than manually operated machines, they can produce parts more uniformly, they are faster, and the long-run tooling costs are lower. The development of NC led to the development of several other innovations in manufacturing technology: Electrical discharge machining,Laser cutting,Electron beam welding.Numerical control has also made machine tools more versatile than their manually operated predecessors. An NC machine tool can automatically produce a wide of parts, each involving an assortment of widely varied and complex machining processes. Numerical control has allowed manufacturers to undertake the production of products that would not have been feasible from an economic perspective using manually controlled machine tolls and processes.Like so many advanced technologies, NC was born in the laboratories of the Massachusetts Institute of Technology. The concept of NC was developed in the early 1950s with funding provided by the U.S. Air Force. In its earliest stages, NC machines were able to made straight cuts efficiently and effectively. 2 Numerical ControlOne of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC). Prior to the advent of NC, all machine tools ere manually operated and controlled. Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator. Numerical control represents the first major step away from human control of machine tools. Numerical control means the control of machine tools and other manufacturing systems through the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool. For a machine tool to be numerically controlled, it must be interfaced with a device for accepting and decoding the programmed instructions, known as a reader.Numerical control was developed to overcome the limitation of human operators, and it has done so. Numerical control machines are more accurate than manually operated machines, they can produce parts more uniformly, they are faster, and the long-run tooling costs are lower. The development of NC led to the development of several other innovations in manufacturing technology: Electrical discharge machining,Laser cutting,Electron beam welding.Numerical control has also made machine tools more versatile than their manually operated predecessors. An NC machine tool can automatically produce a wide of parts, each involving an assortment of widely varied and complex machining processes. Numerical control has allowed manufacturers to undertake the production of products that would not have been feasible from an economic perspective using manually controlled machine tolls and processes.Like so many advanced technologies, NC was born in the laboratories of the Massachusetts Institute of Technology. The concept of NC was developed in the early 1950s with funding provided by the U.S. Air Force. In its earliest stages, NC machines were able to made straight cuts efficiently and effectively. However, curved paths were a problem because the machine tool had to be programmed to undertake a series of horizontal and vertical steps to produce a curve. The shorter the straight lines making up the steps, the smoother is the curve, Each line segment in the steps had to be calculated. This problem led to the development in 1959 of the Automatically Programmed Tools (APT) language. This is a special programming language for NC that uses statements similar to English language to define the part geometry, describe the cutting tool configuration, and specify the necessary motions. The development of the APT language was a major step forward in the fur ther development from those used today. The machines had hardwired logic circuits. The instructional programs were written on punched paper, which was later to be replaced by magnetic plastic tape. A tape reader was used to interpret the instructions written on the tape for the machine. Together, all of this represented a giant step forward in the control of machine tools. However, there were a number of problems with NC at this point in its development.A major problem was the fragility of the punched paper tape medium. It was common for the paper tape containing the programmed instructions to break or tear during a machining process. This problem was exacerbated by the fact that each successive time a part was produced on a machine tool, the paper tape carrying the programmed instructions had to be rerun through the reader. If it was necessary to produce 100 copies of a given part, it was also necessary to run the paper tape through the reader 100 separate tines. Fragile paper tapes simply could not withstand the rigors of a shop floor environment and this kind of repeated use.This led to the development of a special magnetic plastic tape. Whereas the paper carried the programmed instructions as a series of holes punched in the tape, the plastic tape carried the instructions as a series of magnetic dots. The plastic tape was much stronger than the paper tape, which solved the problem of frequent tearing and breakage. However, it still left two other problems.The most important of these was that it was difficult or impossible to change the instructions entered on the tape. To made even the most minor adjustments in a program of instructions, it was necessary to interrupt machining operations and make a new tape. It was also still necessary to run the tape through the reader as many times as there were parts to be produced. Fortunately, computer technology became a reality and soon solved the problems of NC associated with punched paper and plastic tape.The development of a concept known as direct numerical control (DNC) solved the paper and plastic tape problems associated with numerical control by simply eliminating tape as the medium for carrying the programmed instructions. In direct numerical control, machine tools are tied, via a data transmission link, to a host computer. Programs for operating the machine tools are stored in the host computer and fed to the machine tool an needed via the data transmission linkage. Direct numerical control represented a major step forward over punched tape and plastic tape. However, it is subject to the same limitations as all technologies that depend on a host computer. When the host computer goes down, the machine tools also experience downtime. This problem led to the development of computer numerical control.3 TurningThe engine lathe, one of the oldest metal removal machines, has a number of useful and highly desirable attributes. Today these lathes are used primarily in small shops where smaller quantities rather than large production runs are encountered.The engine lathe has been replaced in todays production shops by a wide variety of automatic lathes such as automatic of single-point tooling for maximum metal removal, and the use of form tools for finish on a par with the fastest processing equipment on the scene today.Tolerances for the engine lathe depend primarily on the skill of the operator. The design engineer must be careful in using tolerances of an experimental part that has been produced on the engine lathe by a skilled operator. In redesigning an experimental part for production, economical tolerances should be used.Turret Lathes Production machining equipment must be evaluated now, more than ever before, this criterion for establishing the production qualification of a specific method, the turret lathe merits a high rating. In designing for low quantities such as 100 or 200 parts, it is most economical to use the turret lathe. In achieving the optimum tolerances possible on the turrets lathe, the designer should strive for a minimum of operations.Automatic Screw Machines Generally, automatic screw machines fall into several categories; single-spindle automatics, multiple-spindle automatics and automatic chucking machines. Originally designed for rapid, automatic production of screws and similar threaded parts, the automatic screw machine has long since exceeded the confines of this narrow field, and today plays a vital role in the mass production of a variety of precision parts. Quantities play an important part in the economy of the parts machined on the automatic screw machine. Quantities less than on the automatic screw machine. The cost of the parts machined can be reduced if the minimum economical lot size is calculated and the proper machine is selected for these quantities.Automatic Tracer Lathes Since surface roughness depends greatly on material turned, tooling , and feeds and speeds employed, minimum tolerances that can be held on automatic tracer lathes are not necessarily the most economical tolerances.In some cases, tolerances of 0.05mm are held in continuous production using but one cut . groove width can be held to 0.125mm on some parts. Bores and single-point finishes can be held to 0.0125mm. On high-production runs where maximum output is desirable, a minimum tolerance of 0.125mm is economical on both diameter and length of turn. 中文翻譯:1.車床車床主要是為了進(jìn)行車外圓、車端面和鏜孔等項(xiàng)工作而設(shè)計(jì)的機(jī)床。車削很少在其他種類的機(jī)床上進(jìn)行,而且任何一種其他機(jī)床都不能像車床那樣方便地進(jìn)行車削加工。由于車床還可以用來鉆孔和鉸孔,車床的多功能性可以使工件在一次安裝中完成幾種加工。因此,在生產(chǎn)中使用的各種車床比任何其他種類的機(jī)床都多。車床的基本部件有:床身、主軸箱組件、尾座組件、溜板組件、絲杠和光杠。床身是車床的基礎(chǔ)件。它能常是由經(jīng)過充分正火或時(shí)效處理的灰鑄鐵或者球墨鐵制成。它是一個(gè)堅(jiān)固的剛性框架,所有其他基本部件都安裝在床身上。通常在床身上有內(nèi)外兩組平行的導(dǎo)軌。有些制造廠對(duì)全部四條導(dǎo)軌都采用導(dǎo)軌尖朝上的三角形導(dǎo)軌(即山形導(dǎo)軌),而有的制造廠則在一組中或者兩組中都采用一個(gè)三角形導(dǎo)軌和一個(gè)矩形導(dǎo)軌。導(dǎo)軌要經(jīng)過精密加工以保證其直線度精度。為了抵抗磨損和擦傷,大多數(shù)現(xiàn)代機(jī)床的導(dǎo)軌是經(jīng)過表面淬硬的,但是在操作時(shí)還應(yīng)該小心,以避免損傷導(dǎo)軌。導(dǎo)軌上的任何誤差,常常意味著整個(gè)機(jī)床的精度遭到破壞。主軸箱安裝在內(nèi)側(cè)導(dǎo)軌的固定位置上,一般在床身的左端。它提供動(dòng)力,并可使工件在各種速度下回轉(zhuǎn)。它基本上由一個(gè)安裝在精密軸承中的空心主軸和一系列變速齒輪(類似于卡車變速箱)所組成。通過變速齒輪,主軸可以在許多種轉(zhuǎn)速下旋轉(zhuǎn)。大多數(shù)車床有812種轉(zhuǎn)速,一般按等比級(jí)數(shù)排列。而且在現(xiàn)代機(jī)床上只需扳動(dòng)24個(gè)手柄,就能得到全部轉(zhuǎn)速。一種正在不斷增長的趨勢是通過電氣的或者機(jī)械的裝置進(jìn)行無級(jí)變速。由于機(jī)床的精度在很大程度上取決于主軸,因此,主軸的結(jié)構(gòu)尺寸較大,通常安裝在預(yù)緊后的重型圓錐滾子軸承或球軸承中。主軸中有一個(gè)貫穿全長的通孔,長棒料可以通過該孔送料。主軸孔的大小是車床的一個(gè)重要尺寸,因此當(dāng)工件必須通過主軸孔供料時(shí),它確定了能夠加工的棒料毛坯的最大尺寸。尾座組件主要由三部分組成。底板與床身的內(nèi)側(cè)導(dǎo)軌配合,并可以在導(dǎo)軌上作縱向移動(dòng)。底板上有一個(gè)可以使整個(gè)尾座組件夾緊在任意位置上的裝置。尾座體安裝在底板上,可以沿某種類型的鍵槽在底板上橫向移動(dòng),使尾座能與主軸箱中的主軸對(duì)正。尾座的第三個(gè)組成部分是尾座套筒。它是一個(gè)直徑通常大約在5176mm(23英寸)之間的鋼制空心圓柱體。通過手輪和螺桿,尾座套筒可以在尾座體中縱向移入和移出幾個(gè)英寸。車床的規(guī)格用兩個(gè)尺寸表示。第一個(gè)稱為車床的床面上最大加工直徑。這是在車床上能夠旋轉(zhuǎn)的工件的最大直徑。它大約是兩頂尖連線與導(dǎo)軌上最近點(diǎn)之間距離的兩倍。第二個(gè)規(guī)格尺寸是兩頂尖之間的最大距離。車床床面上最大加工直徑表示在車床上能夠車削的最大工件直徑,而兩頂尖之間的最大距離則表示在兩個(gè)頂尖之間能夠安裝的工件的最大長度。普通車床是生產(chǎn)中最經(jīng)常使用的車床種類。它們是具有前面所敘的所有那些部件的重載機(jī)床,并且除了小刀架之外,全部刀具的運(yùn)動(dòng)都有機(jī)動(dòng)進(jìn)給。它們的規(guī)格通常是:車床床面上最大加工直徑為305610mm(1224英寸);但是,床面上最大加工直徑達(dá)到1270mm(50英寸)和兩頂尖之間距離達(dá)到3658mm的車床也并不少見。這些車床大部分都有切屑盤和一個(gè)安裝在內(nèi)部的冷卻液循環(huán)系統(tǒng)。小型的普通車床車床床面最大加工直徑一般不超過330mm(13英寸)-被設(shè)計(jì)成臺(tái)式車床,其床身安裝在工作臺(tái)或柜子上。雖然普通車床有很多用途,是很有用的機(jī)床,但是更換和調(diào)整刀具以及測量工件花費(fèi)很多時(shí)間,所以它們不適合在大量生產(chǎn)中應(yīng)用。通常,它們的實(shí)際加工時(shí)間少于其總加工時(shí)間的30%。此外,需要技術(shù)熟練的工人來操作普通車床,這種工人的工資高而且很難雇到。然而,操作工人的大部分時(shí)間卻花費(fèi)在簡單的重復(fù)調(diào)整和觀察切屑過程上。因此,為了減少或者完全不雇用這類熟練工人,六角車床、螺紋加工車床和其他類型的半自動(dòng)和自動(dòng)車床已經(jīng)很好地研制出來,并已經(jīng)在生產(chǎn)中得到廣泛應(yīng)用。2.數(shù)字控制先進(jìn)制造技術(shù)中的一個(gè)基本的概念是數(shù)字控制(NC)。在數(shù)控技術(shù)出現(xiàn)之前,所有的機(jī)床都是由人工操縱和控制的。在與人工控制的機(jī)床有關(guān)的很多局限性中,操作者的技能大概是最突出的問題。采用人工控制是,產(chǎn)品的質(zhì)量直接與操作者的技能有關(guān)。數(shù)字控制代表了從人工控制機(jī)床走出來的第一步。數(shù)字控制意味著采用預(yù)先錄制的、存儲(chǔ)的符號(hào)指令來控制機(jī)床和其他制造系統(tǒng)。一個(gè)數(shù)控技師的工作不是去操縱機(jī)床,而是編寫能夠發(fā)出機(jī)床操縱指令的程序。對(duì)于一臺(tái)數(shù)控機(jī)床,其上必須安有一個(gè)被稱為閱讀機(jī)的界面裝置,用來接受和解譯出編程指令。發(fā)展數(shù)控技術(shù)是為了克服人類操作者的局限性,而且它確實(shí)完成了這項(xiàng)工作。數(shù)字控制的機(jī)器比人工操縱的機(jī)器精度更高、生產(chǎn)出零件的一致性更好、生產(chǎn)速度更快、而且長期的工藝裝備成本更低。數(shù)控技術(shù)的發(fā)展導(dǎo)致了制造工藝中其他幾項(xiàng)新發(fā)明的產(chǎn)生: 電火花加工技術(shù)、激光切割、電子束焊接數(shù)字控制還使得機(jī)床比它們采用有人工操的前輩們的用途更為廣泛。一臺(tái)數(shù)控機(jī)床可以自動(dòng)生產(chǎn)很多類的零件,每一個(gè)零件都可以有不同的和復(fù)雜的加工過程。數(shù)控可以使生產(chǎn)廠家承擔(dān)那些對(duì)于采用人工控制的機(jī)床和工藝來說,在經(jīng)濟(jì)上是不劃算的產(chǎn)品生產(chǎn)任務(wù)。同許多先進(jìn)技術(shù)一樣,數(shù)控誕生于麻省理工學(xué)院的實(shí)驗(yàn)室中。數(shù)控這個(gè)概念是50年代初在美國空軍的資助下提出來的。在其最初的價(jià)段,數(shù)控機(jī)床可以經(jīng)濟(jì)和有效地進(jìn)行直線切割。然而,曲線軌跡成為機(jī)床加工的一個(gè)問題,在編程時(shí)應(yīng)該采用一系列的水平與豎直的臺(tái)階來生成曲線。構(gòu)成臺(tái)階的每一個(gè)線段越短,曲線就越光滑。臺(tái)階中的每一個(gè)線段都必須經(jīng)過計(jì)算。在這個(gè)問題促使下,于1959年誕生了自動(dòng)編程工具(APT)語言。這是一個(gè)專門適用于數(shù)控的編程語言,使用類似于英語的語句來定義零件的幾何形狀,描述切削刀具的形狀和規(guī)定必要的運(yùn)動(dòng)。APT語言的研究和發(fā)展是在數(shù)控技術(shù)進(jìn)一步發(fā)展過程中的一大進(jìn)步。最初的數(shù)控系統(tǒng)下今天應(yīng)用的數(shù)控系統(tǒng)是有很大差別的。在那時(shí)的機(jī)床中,只有硬線邏輯電路。指令程序?qū)懺诖┛准垘希ㄋ髞肀凰芰蠋〈?,采用帶閱讀機(jī)將寫在紙帶或磁帶上的指令給機(jī)器翻譯出來。所有這些共同構(gòu)成了機(jī)床數(shù)字控制方面的巨大進(jìn)步。然而,在數(shù)控發(fā)展的這個(gè)階段中還存在著許多問題。 一個(gè)主要問題是穿孔紙帶的易損壞性。在機(jī)械加工過程中,載有編程指令信息的紙帶斷裂和被撕壞是常見的事情。在機(jī)床上每加工一個(gè)零件,都需要將載有編程指令的紙帶放入閱讀機(jī)中重新運(yùn)行一次。因此,這個(gè)問題變得很嚴(yán)重。如果需要制造100個(gè)某種零件,則應(yīng)該將紙帶分別通過閱讀機(jī)100次。易損壞的紙帶顯然不能承受嚴(yán)配的車間環(huán)境和這種重復(fù)使用。這就導(dǎo)致了一種專門的塑料磁帶的研制。在紙帶上通過采用一系列的小孔來載有編程指令,而在塑料帶上通過采用一系列的磁點(diǎn)瞇載有編程指令。塑料帶的強(qiáng)度比紙帶的強(qiáng)度要高很多,這就可以解決常見的撕壞和斷裂問題。然而,它仍然存在著兩個(gè)問題。其中最重要的一個(gè)問題是,對(duì)輸入到帶中指令進(jìn)行修改是非常困難的,或者是根本不可能的。即使對(duì)指令程序進(jìn)行最微小的調(diào)整,也必須中斷加工,制作一條新帶。而且?guī)ㄟ^閱讀機(jī)的次數(shù)還必須與需要加工的零件的個(gè)數(shù)相同。幸運(yùn)的是,計(jì)算機(jī)技術(shù)的實(shí)際應(yīng)用很快解決了數(shù)控技術(shù)中與穿孔紙帶和塑料帶有關(guān)的問題。在形成了直接數(shù)字控制(DNC)這個(gè)概念之后,可以不再采用紙帶或塑料帶作為編程指令的載體,這樣就解決了與之有關(guān)的問題。在直接數(shù)字控制中,幾臺(tái)機(jī)床通過數(shù)據(jù)傳輸線路聯(lián)接到一臺(tái)主計(jì)算機(jī)上。操縱這些機(jī)床所需要的程序都存儲(chǔ)在這臺(tái)主計(jì)算機(jī)中。當(dāng)需要時(shí),通過數(shù)據(jù)傳輸線路提供給每臺(tái)機(jī)床。直接數(shù)字控制是在穿孔紙帶和塑料帶基礎(chǔ)上的一大進(jìn)步。然而,它敢有著同其他信賴于主計(jì)算機(jī)技術(shù)一樣的局限性。當(dāng)主計(jì)算機(jī)出現(xiàn)故障時(shí),由其控制的所有機(jī)床都將停止工作。這個(gè)問題促使了計(jì)算機(jī)數(shù)字控制技術(shù)的產(chǎn)生。微處理器的發(fā)展為可編程邏輯控制器和微型計(jì)算機(jī)的發(fā)展做好了準(zhǔn)備。這兩種技術(shù)為計(jì)算機(jī)數(shù)控(CNC)的發(fā)打下了基礎(chǔ)。采用CNC技術(shù)后,每臺(tái)機(jī)床上都有一個(gè)可編程邏輯控制器或者微機(jī)對(duì)其進(jìn)行數(shù)字控制。這可以使得程序被輸入和存儲(chǔ)在每臺(tái)機(jī)床內(nèi)部。它還可以在機(jī)床以外編制程序,并將其下載到每臺(tái)機(jī)床中。計(jì)算機(jī)數(shù)控解決了主計(jì)算機(jī)發(fā)生故障所帶來的問題,但是它產(chǎn)生了另一個(gè)被稱為數(shù)據(jù)管理的問題。同一個(gè)程序可能要分別裝入十個(gè)相互之間沒有通訊聯(lián)系的微機(jī)中。這個(gè)問題目前正在解決之中,它是通過采用局部區(qū)域網(wǎng)絡(luò)將各個(gè)微機(jī)聯(lián)接起來,以得于更好地進(jìn)行數(shù)據(jù)管理。3.車削加工普通車床作為最早的金屬切削機(jī)床的一種,目前仍然有許多有用的和為人要的特性和為人們所需的特性。現(xiàn)在,這些機(jī)床主要用在規(guī)模較小的工廠中,進(jìn)行小批量的生產(chǎn),而不是進(jìn)行大批量的和產(chǎn)。在現(xiàn)代的生產(chǎn)車間中,普通車床已經(jīng)被種類繁多的自動(dòng)車床所取代,諸如自動(dòng)仿形車床,六角車床和自動(dòng)螺絲車床?,F(xiàn)在,設(shè)計(jì)人員已經(jīng)熟知先利用單刃刀具去除大量的金屬余量,然后利用成型刀具獲得表面光潔度和精度這種加工方法的優(yōu)點(diǎn)。這種加工方法的生產(chǎn)速度與現(xiàn)在工廠中使用的最快的加工設(shè)備的速度相等。普通車床的加偏差主要信賴于操作者的技術(shù)熟練程度。設(shè)計(jì)工程師應(yīng)該認(rèn)真地確定由熟練工人在普通車床上加工的試驗(yàn)件的公差。在把試驗(yàn)伯重新設(shè)計(jì)為生產(chǎn)零件時(shí),應(yīng)該選用經(jīng)濟(jì)的公差。六角車床 對(duì)生產(chǎn)加工設(shè)備來說,目前比過去更注重評(píng)價(jià)其是否具有精確的和快速的重復(fù)加工能力。應(yīng)用這個(gè)標(biāo)準(zhǔn)來評(píng)價(jià)具體的加工方法,六角車床可以獲得較高的質(zhì)量評(píng)定。在為小批量的零件(100200件)設(shè)計(jì)加工方法時(shí),采用六角車床是最經(jīng)濟(jì)的。為了在六角車床上獲得盡可能小的公差值,設(shè)計(jì)人員應(yīng)該盡量將加工工序的數(shù)目減至最少。自動(dòng)螺絲車床 自動(dòng)螺絲車床通被分為以下幾種類型:單軸自動(dòng)、多軸自動(dòng)和自動(dòng)夾緊車床。自動(dòng)螺絲車床最初是被用來對(duì)螺釘和類似的帶有螺紋的零件進(jìn)行自動(dòng)化和快速加工的。但是,這種車床的用途早就超過了這個(gè)狹窄的范圍?,F(xiàn)在,它在許多種類的精密零件的大批量生產(chǎn)中起著重要的作用。工件的數(shù)量對(duì)采用自動(dòng)螺絲車床所加工的零件的經(jīng)濟(jì)性有較大的影響。如果工件的數(shù)量少于1000件,在六角車床上進(jìn)行加工比在自動(dòng)螺絲車床上加工要經(jīng)濟(jì)得多。如果計(jì)算出最小經(jīng)濟(jì)批量,并且針對(duì)工件批量正確地選擇機(jī)床,就會(huì)降低零件的加工成本。自動(dòng)仿形車床 因?yàn)榱慵谋砻娲植诙仍诤艽蟪潭壬先Q于工件材料、刀具、進(jìn)給量和切削速度,采用自動(dòng)仿形車床加工所得到的最小公差一定是最經(jīng)濟(jì)的公差。在某些情況下,在連續(xù)生產(chǎn)過程中,只進(jìn)行一次切削加工時(shí)的公差可以達(dá)到0.05mm。對(duì)于某些零件,槽寬的公差可以達(dá)到0.125mm。鏜孔和休用單刃刀具進(jìn)行精加工時(shí),公差可達(dá)到0.0125mm。在希望獲得最大主量的大批量生產(chǎn)中,進(jìn)行直徑和長度的車削時(shí)的最小公差值為0.125mm是經(jīng)濟(jì)的。
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