【正文】
KL — 考慮到長度不同時(shí)的影響系數(shù),簡稱長度系數(shù),查表 82; P0 — 單根 V帶的基本額定功率,查表 84a或 84b; △ P0 — 記入傳動(dòng)比時(shí)影響是,單根 V 帶額定功率的增量,其值見表 84b 或85d以上均查表的: Pca=,P0=,△ P0=, Kα =, KL= 取 Z=4 確定帶的預(yù)緊力 F0 由式( 87),并考慮離心力的不利影響時(shí),單根 V帶所需的預(yù)緊力為 (44) 將 代入上式并考慮包角對(duì)所需預(yù)緊力的影響,可將 F0的計(jì)算式寫為 將 Pca=, Z=4, V=3m/s, Kα =,q=得: 計(jì)算帶傳動(dòng)作用在軸上的力(簡稱壓力軸) Fp 為了設(shè)計(jì)安裝帶輪的軸和軸承,必須確定帶傳動(dòng)作用在軸上的力 Fp。根據(jù)表153,取 A0=120,于是得: 軸的最小直徑顯然是安裝 V帶以動(dòng)輪出的直徑 dⅠ Ⅱ =35mm 軸的結(jié)構(gòu)設(shè)計(jì) 11 擬定軸上零件的裝配方案 本軸的裝配方案采用如圖 3所示的裝配方案 圖 4 軸的結(jié)構(gòu)與裝配 Figure4 Structure and assembly of the axis 初步選擇軸承。由手冊(cè)上查得 7209AC型軸承的定位軸肩高度 h=17mm,因此 dⅣ Ⅶ =52mm。 軸環(huán)寬度 b=12mm,則 lⅤ Ⅵ =12mm。軸承與軸的周向定位是借過渡配合來保證的,此處選軸的直徑尺寸公差為 m6。在確定軸承的支點(diǎn)位置時(shí),應(yīng)從手冊(cè)中查取 a值。 現(xiàn)將計(jì)算出截面 C處的 MH、 Mv及 M的值 (列表 3) 13 圖 5 軸的載荷分析圖 Figure5 Axis load analysis diagram 表 3 截面 C 處的 MH、 Mv 及 M 的值 14 Table 3 Section C at the MH, Mv and the value of M 載荷 水平面 H 垂直面 V 支反力 F FNH1=2337N FNH2=1273N FNV1=1689N FNV2=15N 彎矩 M MH=36217Nmm 按彎矩合成重力校核軸的強(qiáng)度 進(jìn)行校核是,通常只校核對(duì)軸上承受最大彎矩和扭矩的截面(即能是截面 C)的強(qiáng)度,根據(jù)式( 155)及上表中的數(shù)值,并去α =,軸的計(jì)算重力 (45) 將 ,M1= 精確校核軸的疲勞強(qiáng)度 判斷危險(xiǎn)截面 截面 A,Ⅱ,Ⅲ, B 只受扭矩作用,雖然鍵槽、軸肩及過渡配合所引起的重力集中均將削弱軸的疲勞強(qiáng)度,但由于軸的最小直徑是按鈕強(qiáng)度較為寬裕的確定的,所以截面A,Ⅱ,Ⅲ, B均無需校核。截面Ⅵ和Ⅶ顯然更不必校核。由表 151查得 , , 。 32 得碳鋼的特性系數(shù) ,取 取 于是,計(jì)算安全系數(shù) Sca值,按式( 156)( 158)則得 故可知其安全 截面Ⅳ右側(cè) 抗彎截面系數(shù)的 W按表 154中的公式計(jì)算 抗扭截面系數(shù) WT 為 彎矩 M及彎曲應(yīng)力為 扭矩 T及扭轉(zhuǎn)應(yīng)力為 T=38000N 所以 求兩軸承當(dāng)量動(dòng)載荷 因?yàn)? 17 由表 135可查得徑向載荷系數(shù)和軸荷系數(shù)為 對(duì)軸承 1 X1=1 Y1=0 對(duì)軸承 2 X2=1 Y2=0 固軸承運(yùn)轉(zhuǎn)中有中等沖擊載荷,按表 136, ,則: 最后求 驗(yàn)算軸承的壽命 因?yàn)?,所以按軸承 1的受力大小驗(yàn)算; 預(yù)期壽命 8年 工作小時(shí)數(shù): 固有 ,可滿足壽命要求。 18 圖 6 箱蓋 Figure6 Cover 圖 7 箱體 Figure7 Box 入料斗的結(jié)構(gòu)設(shè)計(jì) 19 入料斗 (如圖 8)是保證進(jìn)料順利,起定料的作用,根據(jù)本機(jī)的整體特點(diǎn),入料斗設(shè)計(jì)成矩形和梯形相結(jié)合的形狀,且矩形的寬度為 40mm,能保證剛好一個(gè)核桃進(jìn)入齒盤進(jìn)行剝殼。 由于電機(jī)的轉(zhuǎn)速過高,而分離裝置轉(zhuǎn)速要求較小,故通過減速達(dá)到所需要求。取θ =30176。帶傳動(dòng)計(jì)算過程參照上面方法,滿足所需要求。 參考文獻(xiàn) [1]鐘海雁等 . 核桃生產(chǎn)加工利用研究的現(xiàn)狀與前景 [J]. 食品與機(jī)械 , 2022,(04) [2]吳子岳 . 綿核桃剝殼機(jī)的研究設(shè)計(jì) [J]. 食品與機(jī)械 , 2022,(03) [3]史建新, 辛動(dòng)軍 等 .國內(nèi)外核桃破殼取仁機(jī)械的現(xiàn)狀及問題探討 [J]. 新疆農(nóng)機(jī)化 , 2022,(06) [4]張林泉 .剝殼機(jī)具的現(xiàn)狀及效果改進(jìn)方法的探討 [J] .食品與機(jī)械 .2022( 4) [5]史建新等 . 6HP150型核桃破殼機(jī) [J].糧油加工與食品機(jī)械 , 2022,(01) [6]吳斌芳,張建鋼,周國柱,張業(yè)鵬 . 綿核桃剝殼取仁機(jī)的研制 [J].湖北工學(xué)院學(xué)報(bào) ,2022,(S1) [7]辛動(dòng)軍 ,史建新 . 核桃剝殼機(jī)導(dǎo)向裝置試驗(yàn)研究 [J]. 新疆農(nóng)業(yè)大學(xué)學(xué)報(bào) , 2022,(03) [8]吳斌芳等 . 綿核桃機(jī)械剝殼取仁參數(shù)選擇及實(shí)驗(yàn)分析 [J]. 湖北工學(xué)院學(xué)報(bào) , 2022,(04) [9]吳子岳 . 綿核桃剝殼取仁機(jī)械的研究 [J]. 農(nóng)業(yè)工程學(xué)報(bào) , 2022,(04) [10]王昆 .何小柏 .汪信遠(yuǎn) ..機(jī)械設(shè)計(jì)課程設(shè)計(jì) .[M].高等教育出版社, 2022,( 12) 22 [11]吳子岳 . 核桃剝殼的力學(xué)分析 [J]. 南京農(nóng)業(yè)大學(xué)學(xué)報(bào) , 2022,(03) [12]張仲欣 . 對(duì)輥窩眼式核桃開口機(jī)設(shè)計(jì) [J]. 洛陽工學(xué)院學(xué)報(bào) , 2022,(04) [13]邱宣懷 . 機(jī)械設(shè)計(jì) . 4 版 . 北京 : 高等教育出版社 , 2022(04) [14]王步瀛 . 機(jī)械零件強(qiáng)度計(jì)算的理論和方法 . 北京 : 高等教育出版社 , 2022(06) [15]濮良貴 .紀(jì)名剛 . 機(jī)械設(shè)計(jì) . 8版 北京 : 高等教育出版社 2022(05) 致 謝 經(jīng)過近半學(xué)期的忙碌和工作,本次畢業(yè)設(shè)計(jì)已經(jīng)接近尾聲, 作為一個(gè)本科生的畢業(yè)設(shè)計(jì),由于經(jīng)驗(yàn)的匱乏,難免有許多考慮不周全的地方,如果沒有導(dǎo)師的督促指導(dǎo),以及一起學(xué)習(xí)的同學(xué)們的支持,想要完成這個(gè)設(shè)計(jì)是難以想象的。除了敬佩 高 老師的專業(yè)水平外, 她 的治學(xué)嚴(yán)謹(jǐn)和科學(xué)研究的精神也是我永遠(yuǎn)學(xué)習(xí)的榜樣, 她 的循循善誘的教導(dǎo)和不拘一格的思 路也給予我無盡的啟迪。在此,我謝謝大家 ! 23 為你提供優(yōu)秀的畢業(yè)論文參考資料,請(qǐng)您刪除以下內(nèi)容, O(∩_∩)O 謝謝!??! 2 Many people have the same mixed feelings when planning a trip during Golden Week. With heaps of time, the sevenday Chinese 為你提供優(yōu)秀的畢業(yè)論文設(shè)計(jì)參考資料,請(qǐng)您刪除一下內(nèi)容, O(∩_∩)O 謝謝!??! National Day holiday could be the best occasion to enjoy a destination. However, it can also be the easiest way to ruin how you feel about a place and you may bee more fatigued after the holiday, due to battling the large crowds. During peak season, a dream about a place can turn to nightmare without careful planning, especially if you travel with children and older people. As most Chinese people will take the holiday to visit domestic tourist destinations, crowds and busy traffic are inevitable at most places. Also to be expected are increasing transport and acmodation prices, with the possibility that there will be no rooms available. It is also mon that you39。s misery, the cow told him to turn its hide into a pair of shoes after it died. The magic shoes whisked Niulang, who carried his two children in baskets strung from a shoulder pole, off on a chase after the empress. The pursuit enraged the empress, who took her hairpin and slashed it across the sky creating the Milky Way which separated husband from wife. But all was not lost as magpies, moved by their love and devotion, formed a bridge across the Milky Way to reunite the family. Even the Jade Emperor was touched, and allowed Niulang and Zhinu to meet once a year on the seventh night of the seventh month. This is how Qixi came to be. The festival can be traced back to the Han Dynasty (206 BCAD 220). Traditionally, people would look up at the sky and find a bright star in the constellation Aquila as well as the star Vega, which are identified as Niulang and Zhinu. The two stars shine on opposite sides of the Milky Way. Customs In bygone days, Qixi was not only a special day for lovers, but also for girls. It is also known as the Begging for Skills Festival or Daughters39。s Day! in shops, hotels and restaurants. But few young women will mark the festival with their boyfriends, or take part in traditional activities to pray for