葵花脫粒機(jī)的設(shè)計(jì)【葵瓜子脫粒機(jī)設(shè)計(jì)】
葵花脫粒機(jī)的設(shè)計(jì)【葵瓜子脫粒機(jī)設(shè)計(jì)】,葵瓜子脫粒機(jī)設(shè)計(jì),葵花脫粒機(jī)的設(shè)計(jì)【葵瓜子脫粒機(jī)設(shè)計(jì)】,葵花,脫粒機(jī),設(shè)計(jì),瓜子
12 屆畢業(yè)論文
葵花脫粒機(jī)的設(shè)計(jì)
設(shè)計(jì)說(shuō)明書(shū)
學(xué)生姓名 王冬梅
學(xué) 號(hào) 8031208138
所屬學(xué)院 機(jī)械電氣化工程學(xué)院
專 業(yè) 農(nóng)業(yè)機(jī)械化及其自動(dòng)化專業(yè)
班 級(jí) 農(nóng)機(jī)12-1
指導(dǎo)教師 萬(wàn)暢
日 期
目錄
前言 1
1緒論 3
1.1葵花的價(jià)值 3
1.2我國(guó)葵花種植區(qū)域及面積 3
1.3研究目的及意義 3
1.4國(guó)內(nèi)研究現(xiàn)狀及分析 4
1.5任務(wù)要求及實(shí)現(xiàn)預(yù)期目標(biāo)的可行性分析 5
1.6完成本課題所必需的工作條件及主要任務(wù) 5
2 葵花脫粒機(jī)的總體結(jié)構(gòu)設(shè)計(jì) 6
2.1入料部分 6
2.2 脫粒部分 6
2.3 篩選部分 7
2.4 機(jī)體部分 7
2.5 葵花脫粒機(jī)的總體設(shè)計(jì) 7
3 葵花脫粒機(jī)的設(shè)計(jì) 8
3.1 配套動(dòng)力的選擇 8
3.2軸的設(shè)計(jì) 8
3.3軸的校核 8
3.4 帶輪的設(shè)計(jì) 9
3.5軸承的選擇 9
4葵花脫粒機(jī)上的標(biāo)準(zhǔn)件的選擇 9
4.1 葵花脫粒機(jī)上的螺栓的選擇 9
4.2鍵的選擇 9
5葵花脫粒機(jī)安全操作規(guī)程注意事項(xiàng) 9
5.1 超速運(yùn)轉(zhuǎn),機(jī)械“爆炸” 9
5.2 禁止過(guò)疲勞或酒后操作 9
5.3 注意事項(xiàng) 9
6 葵花脫粒機(jī)的安裝、調(diào)整和使用 9
6.1 葵花脫粒機(jī)與拖拉機(jī)的連接 9
6.2 調(diào)整 9
6.3試運(yùn)轉(zhuǎn) 9
6.4田間工作 9
7 葵花脫粒機(jī)的保養(yǎng)與維修 9
7.1使用中的保養(yǎng) 9
7.2入庫(kù)停放前的保養(yǎng) 9
總結(jié) 9
致 謝 9
參考文獻(xiàn) 9
前言
畢業(yè)設(shè)計(jì)是大學(xué)本科教育培養(yǎng)目標(biāo)實(shí)現(xiàn)的重要階段，是畢業(yè)前的綜合學(xué)習(xí)階段，是深化、拓寬、綜合教與學(xué)的重要過(guò)程，是對(duì)大學(xué)期間所學(xué)專業(yè)知識(shí)的全面綜合和總結(jié)。
在畢業(yè)設(shè)計(jì)過(guò)程中，經(jīng)過(guò)資料查閱、設(shè)計(jì)計(jì)算、說(shuō)明書(shū)的編寫(xiě)，加深了對(duì)新規(guī)范、規(guī)程、手冊(cè)等專業(yè)技術(shù)相關(guān)內(nèi)容的新認(rèn)識(shí)和理解，畢業(yè)設(shè)計(jì)順利的完成與導(dǎo)師的認(rèn)真詳細(xì)指導(dǎo)分不開(kāi)。本次設(shè)計(jì)鞏固了我的專業(yè)知識(shí)、提高了綜合分析、解決問(wèn)題的能力。在進(jìn)行制圖時(shí)，主要應(yīng)用了CAD設(shè)計(jì)軟件，對(duì)其有了更深一步的了解。從不同方面達(dá)到了畢業(yè)設(shè)計(jì)的目的及要求。
本設(shè)計(jì)說(shuō)明書(shū)要闡述葵花脫粒機(jī)的結(jié)構(gòu)與工作原理，著重對(duì)葵花脫粒機(jī)的核心脫粒部件進(jìn)行了大量工作與分析。通過(guò)對(duì)大量參考文獻(xiàn)的閱讀與分析，對(duì)葵花脫粒機(jī)的國(guó)內(nèi)發(fā)展現(xiàn)狀有了一定了解，對(duì)結(jié)構(gòu)和參數(shù)進(jìn)行了優(yōu)化，盡可能使葵花脫粒機(jī)的結(jié)構(gòu)更合理、參數(shù)更準(zhǔn)確、工作更快捷，經(jīng)濟(jì)使用性更好。
機(jī)械，在我國(guó)廣大農(nóng)村使用十分廣泛。脫粒機(jī)在我國(guó)生產(chǎn)使用已有數(shù)十年的歷史，將葵花籽（谷物）從作物的穗頭上分離下來(lái)所使用的機(jī)具，稱為脫粒機(jī)具。質(zhì)量合格的脫粒機(jī)，應(yīng)該是堅(jiān)固耐用的、故障少、使用保養(yǎng)方便、結(jié)構(gòu)簡(jiǎn)單可靠。同時(shí)，還應(yīng)滿足以下的農(nóng)業(yè)技術(shù)要求：葵花籽應(yīng)當(dāng)從葵花盤上脫下來(lái)，脫粒要干凈。脫下的葵花籽不要破碎、情潔、不混其它葵花盤、雜物等脫粒時(shí)應(yīng)盡量減少葵花盤的損壞，以保證葵花籽的完整。脫粒機(jī)在一定程度上應(yīng)有一定的通用性，盡可能適用于托多種農(nóng)作物，從而以提高機(jī)具的利用率。所設(shè)計(jì)的脫粒機(jī)應(yīng)有較高的生產(chǎn)率，功率消耗少，即其造價(jià)低。脫粒系統(tǒng)是聯(lián)合收割機(jī)的核心，它決定著其他各部分的工作性能。研究脫?？臻g內(nèi)谷物的運(yùn)動(dòng)規(guī)律是聯(lián)合收割機(jī)脫粒機(jī)理研究的關(guān)鍵內(nèi)容之一。
脫粒機(jī)生產(chǎn)在我國(guó)雖已有數(shù)十年歷史，但不少企業(yè)仍延襲十幾年以前的生產(chǎn)方式進(jìn)行生產(chǎn)和管理，企業(yè)管理水平相對(duì)落后。全國(guó)200多家企業(yè)中，至今只有１家企業(yè)進(jìn)行了質(zhì)量保證體系認(rèn)證就足以說(shuō)明這一問(wèn)題。此外，產(chǎn)品品種單一，產(chǎn)品更新?lián)Q代適應(yīng)不了市場(chǎng)的需求，一些產(chǎn)品多年存在的性能問(wèn)題，如風(fēng)扇型脫粒機(jī)存在的對(duì)作物干濕度適應(yīng)性差的問(wèn)題一直得不到解決，原因就是多數(shù)企業(yè)經(jīng)濟(jì)效益欠佳，拿不出更多的資金和技術(shù)力量用于科研和開(kāi)發(fā)新產(chǎn)品；也有的是由于企業(yè)領(lǐng)導(dǎo)急功近利，對(duì)開(kāi)發(fā)新產(chǎn)品的重要性認(rèn)識(shí)不足。然而產(chǎn)品更新?lián)Q代的越慢，越難占領(lǐng)市場(chǎng)，企業(yè)效益越差，從而使不少企業(yè)的生產(chǎn)陷入了惡性循壞。
目前脫粒機(jī)生產(chǎn)企業(yè)產(chǎn)量最大的為３萬(wàn)多臺(tái)，最少的僅幾十臺(tái)，不少企業(yè)的生產(chǎn)未能形成適度的規(guī)模。這主要是因?yàn)槊摿C(jī)是季節(jié)性很強(qiáng)的產(chǎn)品，產(chǎn)品銷售往往僅在１個(gè)月或者十幾天的時(shí)間，資金周轉(zhuǎn)時(shí)間長(zhǎng)，不少企業(yè)明知進(jìn)行技術(shù)改造形成適度規(guī)模生產(chǎn)能降低成本，提高經(jīng)濟(jì)效益，但苦于流動(dòng)資金不足或貸款困難，無(wú)力進(jìn)行適度規(guī)模生產(chǎn)，再加上近幾年脫粒機(jī)行業(yè)活動(dòng)和信息交流不暢，不能根據(jù)市場(chǎng)變化及時(shí)調(diào)整生產(chǎn)結(jié)構(gòu)、產(chǎn)品品種及生產(chǎn)數(shù)量，從而導(dǎo)致經(jīng)濟(jì)效益不理想。因此，我們可以看出脫粒機(jī)目前仍有較大的存在空間,對(duì)脫粒機(jī)的改進(jìn)設(shè)計(jì),使其價(jià)格低廉、工作可靠、性能優(yōu)良、盡可能同時(shí)完成多項(xiàng)作業(yè)是時(shí)代的需要。
隨著社會(huì)的進(jìn)步，生活中的每一個(gè)角落都有機(jī)器的參與。農(nóng)業(yè)是我國(guó)的基礎(chǔ)經(jīng)濟(jì)、是國(guó)家發(fā)展的根本，機(jī)械化的普及，不僅使農(nóng)業(yè)加強(qiáng)了農(nóng)業(yè)化生產(chǎn)，同時(shí)也減輕了農(nóng)民的勞動(dòng)強(qiáng)度。據(jù)不完全統(tǒng)計(jì)，我國(guó)北方地區(qū)種植小麥、玉米等農(nóng)作物約占我國(guó)農(nóng)業(yè)經(jīng)濟(jì)的45%以上，同年出口量北方地區(qū)占全國(guó)達(dá)20%左右。因此我國(guó)北方地區(qū)更需要實(shí)現(xiàn)農(nóng)業(yè)機(jī)械化生產(chǎn)，從而提高農(nóng)業(yè)的勞動(dòng)生產(chǎn)率。如今我國(guó)北方大部分地區(qū)基本上從種到收到入倉(cāng)，實(shí)現(xiàn)了機(jī)械化作業(yè)，更值得慶幸的是每種機(jī)械的開(kāi)發(fā)和利用都有相當(dāng)可觀的市場(chǎng)，科技的創(chuàng)新更很好的開(kāi)闊了市場(chǎng)。這里僅對(duì)一種葵花脫粒機(jī)視為課題討論研究，葵花脫粒機(jī)是葵花砍下后，經(jīng)過(guò)一 段時(shí)間的風(fēng)干，然后將葵花利用脫粒機(jī)使葵花籽和葵花盤分開(kāi)，這種機(jī)械就是葵花脫粒機(jī)。
葵花脫粒機(jī)工作原理是：葵花脫粒機(jī)在進(jìn)行葵花脫粒時(shí)，利用脫粒軸體回轉(zhuǎn)運(yùn)動(dòng)的齒條與底篩之間的間隙相配合，使葵花粒拖下（脫粒軸體上的齒條和底篩之間的揉搓作用，將葵花籽脫離葵花盤，并借助其他的機(jī)械機(jī)構(gòu)將葵花籽和葵花盤分別從兩個(gè)不同的出口排出機(jī)體之外，循環(huán)脫粒，不斷的進(jìn)行填入---脫粒---排出機(jī)體。
1緒論
1.1 葵花的價(jià)值
瓜子在人們生活中是不可缺少的零食，葵花子更是瓜子中的佼佼者?？ㄗ硬坏梢宰鳛榱闶常疫€可以作為制作糕點(diǎn)的原料。同時(shí)，由于葵花子是植物的種子，含有大量的油脂，而葵花子油又是近幾年來(lái)深受營(yíng)養(yǎng)學(xué)界推崇的高檔健康油脂，故其還是重要的榨油原料。
對(duì)于葵花子所具有的營(yíng)養(yǎng)價(jià)值以及其食用的普遍性，有如下闡述。
???????一、營(yíng)養(yǎng)分析
?????? 1. 葵花子含豐富的不飽和脂肪酸、優(yōu)質(zhì)蛋白、鉀、磷、鈣、鎂、硒元素及維生素E、維生素B1等營(yíng)養(yǎng)元素；
???????2. 其所含豐富的鉀元素對(duì)保護(hù)心臟功能，預(yù)防高血壓頗多裨益；
????? 3. 葵花子含有豐富的維生素E，有防止衰老、提高免疫力、預(yù)防心血管疾病的作用；
????? 4. 葵花子中所含植物固醇和磷脂，能夠抑制人體內(nèi)膽固醇的合成，防止血漿膽固醇過(guò)多，可防止動(dòng)脈硬化；
???????5. 葵花子還有調(diào)節(jié)腦細(xì)胞代謝，改善其抑制機(jī)能的作用，故可用于催眠。
??????二、相關(guān)人群
??????一般人群均可食用
???????1. 適宜癌癥患者食用；適宜高脂血癥，動(dòng)脈硬化和高血壓之人食用；適宜神經(jīng)衰弱的失眠者食用；適宜蟯蟲(chóng)病人食用；
???????2. 炒后性溫燥，多食易引起口干、口瘡、牙痛等“上火”癥狀。
???? 三、食療作用
葵花籽性平，味甘；有補(bǔ)虛損，降血脂，抗癌之功效。
1.2 我國(guó)葵花種植區(qū)域及面積
改革開(kāi)放以來(lái)，我國(guó)的農(nóng)業(yè)生產(chǎn)和農(nóng)村經(jīng)濟(jì)發(fā)生了翻天覆地的變化。種植業(yè)內(nèi)部也形成了以糧食作物為主，經(jīng)濟(jì)作物和飼料作物為輔的三元結(jié)構(gòu)。作為經(jīng)濟(jì)作物之一的葵花產(chǎn)業(yè)也得到了長(zhǎng)足的發(fā)展，油用葵花已成為四大油料作物之一，食用葵花的發(fā)展更快，在全國(guó)葵花種植面積中占70%以上[1]。我國(guó)的葵花多種植在北方冷涼地區(qū)，從黑龍江一直到，且多分布在干旱瘠薄土地和鹽堿地上，是農(nóng)民增收的一個(gè)非常好的經(jīng)濟(jì)作物。
我國(guó)葵花種植面積約112.53 ，產(chǎn)量約1369kg/,我國(guó)葵花總產(chǎn)在亞洲是大國(guó)與印度處于同一水平，我國(guó)葵花的單產(chǎn)水平略高于世界的平均水平[2]。由于我國(guó)對(duì)葵花的需求量很大，從油料生產(chǎn)情況來(lái)看，我國(guó)葵花生產(chǎn)呈上升趨勢(shì)，葵花籽總產(chǎn)達(dá)170～190萬(wàn)t,在所有油料生產(chǎn)中排位第五位。另外，隨著人民生活水平的日益提高對(duì)食葵的需求量也更大?？ㄊ斋@后，首先需要將葵花脫粒，過(guò)去葵花脫粒基本上是采用手工脫粒，勞工強(qiáng)度大，勞動(dòng)效率低，剛收獲的葵花如果不及時(shí)進(jìn)行脫粒，葵花盤就會(huì)腐爛，這樣就會(huì)給農(nóng)民造成很大的損失。為了降低勞動(dòng)強(qiáng)度，提高勞動(dòng)效率，我們應(yīng)開(kāi)發(fā)采用機(jī)械脫粒。
1.3 研究目的及意義
當(dāng)前，北疆葵花種植區(qū)域主要生產(chǎn)體制實(shí)行的是以戶為單位的聯(lián)產(chǎn)承包制，經(jīng)營(yíng)規(guī)模相對(duì)內(nèi)地大且集中?？摿C(jī)是許多葵花種植農(nóng)戶收獲的首選，因此也推動(dòng)了我們對(duì)葵花脫粒機(jī)的研究。而且隨著人們生活水平的日益提高，瓜子也成了成活中必不可少的零食，葵花的種植面積也不會(huì)有所降低，在今后相當(dāng)長(zhǎng)的時(shí)期內(nèi)葵花脫粒機(jī)有很大的市場(chǎng)需求。
現(xiàn)階段我國(guó)農(nóng)村經(jīng)濟(jì)收入從整體來(lái)說(shuō)還比較低，購(gòu)買力有限，盡管國(guó)家對(duì)購(gòu)買部分大型農(nóng)機(jī)實(shí)行補(bǔ)貼政策，但一次購(gòu)買十萬(wàn)甚至幾十萬(wàn)的高性能脫粒機(jī)還是有困難的，同時(shí)，高性能脫粒機(jī)技術(shù)復(fù)雜，對(duì)經(jīng)營(yíng)者的經(jīng)營(yíng)和管理水平有較高的要求，而小型脫粒機(jī)無(wú)論從購(gòu)買和經(jīng)營(yíng)使用方面對(duì)于一般農(nóng)民來(lái)說(shuō)就容易的多了。
相對(duì)于其他脫粒機(jī)而言，設(shè)計(jì)的該葵花脫粒機(jī)機(jī)體體積小，質(zhì)量輕，生產(chǎn)成本低，省錢省料，而且生產(chǎn)率較高，脫粒效果好，較好的實(shí)現(xiàn)了“又好（生產(chǎn)效率高，脫粒效果好）”、“又省（省錢、省料）”的設(shè)計(jì)理念，符合當(dāng)今建設(shè)資源節(jié)約型社會(huì)的要求。
1.4 國(guó)內(nèi)研究現(xiàn)狀及分析
脫粒機(jī)是用于對(duì)小麥、水稻、玉米、高粱、大豆及其它雜糧等作物進(jìn)行脫粒作業(yè)的重要收獲機(jī)械， 在我國(guó)廣大農(nóng)村使用十分廣泛。脫粒機(jī)在我國(guó)生產(chǎn)使用已有數(shù)十年的歷史， 目前據(jù)不完全統(tǒng)計(jì)， 我國(guó)生產(chǎn)各類脫粒機(jī)的企業(yè)約有200 余家， 年產(chǎn)量在30 萬(wàn)臺(tái)左右。脫粒機(jī)是實(shí)施生產(chǎn)許可證的農(nóng)機(jī)產(chǎn)品之一， 截止1997 年底， 己領(lǐng)取生產(chǎn)許可證的企業(yè)數(shù)為146 家。生產(chǎn)企業(yè)遍布全國(guó)各地， 其中，以長(zhǎng)江以北的麥類產(chǎn)區(qū)分布較多， 產(chǎn)量較大， 尤其山東、河南、河北、江蘇四省生產(chǎn)以脫麥為主的脫粒機(jī)企業(yè)較多， 每省有30 家左右。東北地區(qū)主要是生產(chǎn)以脫玉米、豆類及雜糧為主的脫粒機(jī)。在長(zhǎng)江以南的地區(qū)， 大都為生產(chǎn)人工踩踏或動(dòng)力帶動(dòng)的梳刷式水稻脫粒機(jī)。在西南、西北等地也有一些以生產(chǎn)水稻、小麥類脫粒機(jī)為主的企業(yè)， 雜糧類脫粒機(jī)占有較小比例。生產(chǎn)脫粒機(jī)的企業(yè)， 大都為中小型企業(yè)，尤以小型企業(yè)所占比例較大， 其企業(yè)經(jīng)濟(jì)性質(zhì)多為國(guó)有和集體企業(yè)，但鄉(xiāng)鎮(zhèn)和個(gè)體企業(yè)也為數(shù)不少，也有少數(shù)的大型生產(chǎn)企業(yè)生產(chǎn)脫粒機(jī)， 但脫粒機(jī)產(chǎn)品不是該企業(yè)主導(dǎo)產(chǎn)品。
脫粒機(jī)屬于收獲后處理類農(nóng)業(yè)機(jī)械產(chǎn)品，主要用于水稻、玉米等谷物收獲后的脫粒處理作業(yè)，由于脫粒機(jī)傳動(dòng)機(jī)構(gòu)比較復(fù)雜，高速轉(zhuǎn)動(dòng)部件較多，容易導(dǎo)致人身傷害，所以國(guó)家將其納入工業(yè)產(chǎn)品生產(chǎn)許證目錄管理范疇，嚴(yán)格要求該產(chǎn)品的質(zhì)量安全。脫粒機(jī)按喂入方式分為全喂入式和半喂入式，葵花脫粒機(jī)屬于全喂入式，水稻脫粒機(jī)屬于半喂入式。
在我國(guó)北方很多地區(qū)大面積種植經(jīng)濟(jì)作物葵花，每到收獲的季節(jié)，農(nóng)民最急需解決的問(wèn)題就是脫離問(wèn)題，現(xiàn)有的脫粒裝置一般由滾筒和凹板組成，其種類和形式很多，主要用于谷物脫粒。目前市面上雖然有專用于葵花的脫粒機(jī)，但由于破籽率高，對(duì)葵花籽傷害大，因此收獲時(shí)大部分靠人力敲打脫粒，效率極低。剛采摘的濕葵如不能及時(shí)脫粒，葵花盤很快會(huì)發(fā)熱腐爛，尤其遇到陰雨腐爛的更快，給種植戶造成很大的損失。從已經(jīng)公開(kāi)的有關(guān)葵花脫粒機(jī)的專利申請(qǐng)文件看，大部分結(jié)構(gòu)較為復(fù)雜，操作比較麻煩，有些設(shè)備采用螺旋推進(jìn)器送料，葵花盤被打碎與籽?；旌显谝黄?，不易篩選分離。
1988年內(nèi)蒙工學(xué)院原機(jī)械系為了解決葵花收獲時(shí)農(nóng)民勞動(dòng)強(qiáng)度大、收獲期長(zhǎng)、損失大的問(wèn)題研制了5KT-0.5型葵花脫粒機(jī)[3]。該機(jī)由8.8KW（12馬力）小四輪拖拉機(jī)拖動(dòng)，工作過(guò)程是，葵花盤在入口處被高速滾動(dòng)的滾筒卷入滾筒和柵板弧形間隙中。此時(shí)它受到彎曲、擠壓，開(kāi)始有部分籽粒被脫掉。此后，在葵花盤前進(jìn)過(guò)程中此作用仍在繼續(xù)，并伴有摩擦、碰撞、沖擊等作用，特別是鋼絲扣的揉搓作用，使葵花盤上的葵籽從入口到出口的移動(dòng)中逐漸被脫凈。脫凈的葵花盤從出口由離心力作用飛出，葵籽從集籽斗流出。
1991年吉林省白城地區(qū)農(nóng)牧機(jī)械化研究所和長(zhǎng)嶺縣農(nóng)具廠研制的5TK-900型葵花脫粒機(jī)，5TK-900型葵花脫粒機(jī)是根據(jù)葵花的物理特性和脫粒特點(diǎn)設(shè)計(jì)的[4]。該機(jī)可與小四輪拖拉機(jī)配套，也可以用大于2.0KW的動(dòng)力機(jī)械帶動(dòng)作業(yè)。它采用復(fù)式滾筒，巧妙地將沖擊碾壓、摩擦、剝落、叩打等作用融為一體， 脫粒速度快、脫凈率高、破損少。成熟的葵花，干濕都能脫，脫后基本保持了葵花盤的完整，清潔率高，易于風(fēng)選和晾曬。
5TK-2.0型葵花脫粒機(jī)，該機(jī)由吉林省通榆縣農(nóng)機(jī)推廣站和通榆縣機(jī)電修造廠共同研制產(chǎn)生[5]。作業(yè)時(shí)葵花頭整體喂入，可一次完成推進(jìn)、打擊、揉搓和分離等工序。具有使用方便、脫粒性能好、含雜率低、損失少和效率高等特點(diǎn)。該機(jī)外形尺寸（長(zhǎng)、寬、高）為1419mm，1000mm、1100mm，配套動(dòng)力15kw，滾筒轉(zhuǎn)速500～600r/min，工作效率800kg/h,整體質(zhì)量142kg。
1.5 任務(wù)要求及實(shí)現(xiàn)預(yù)期目標(biāo)的可行性分析
本課題主要是研究葵花脫粒機(jī)的結(jié)構(gòu)及工作原理，目前對(duì)葵花脫粒機(jī)的需求量很大，生產(chǎn)前景廣闊。近年來(lái)國(guó)內(nèi)很多企業(yè)加入了生產(chǎn)行列，使得競(jìng)爭(zhēng)加劇。隨著競(jìng)爭(zhēng)的進(jìn)一步加劇，產(chǎn)品開(kāi)發(fā)手段的完善和創(chuàng)新設(shè)計(jì)能力的提升，必然成為企業(yè)競(jìng)爭(zhēng)的核心內(nèi)容，也是企業(yè)做大的做強(qiáng)的一個(gè)重要法寶。
以往企業(yè)企業(yè)在設(shè)計(jì)葵花脫粒時(shí)往往靠經(jīng)驗(yàn)積累，其特點(diǎn)是適用性不廣，而且有時(shí)往往不可靠。在使用中，現(xiàn)有的葵花脫粒機(jī)普遍存在脫粒效率低，碎籽率高等現(xiàn)象，造成了人工成本高及可靠性低這一結(jié)果，也沒(méi)有為廣大葵花農(nóng)戶帶來(lái)更多收益。在設(shè)計(jì)方面，由于設(shè)計(jì)手段限制，整個(gè)葵花脫粒機(jī)結(jié)構(gòu)不合理，可靠性比較低，維護(hù)不方便。要解決這些問(wèn)題，需要對(duì)葵花脫粒機(jī)設(shè)計(jì)過(guò)程中的關(guān)鍵技術(shù)進(jìn)行深入研究。
1.6 完成本課題所必需的工作條件及主要任務(wù)
完成課題必須深入調(diào)查研究，收集、查閱和閱讀中外文獻(xiàn)資料；綜合運(yùn)用專業(yè)理論與知識(shí)分析解決實(shí)際問(wèn)題；制定方案，對(duì)數(shù)據(jù)進(jìn)行計(jì)算與分析處理；具備設(shè)計(jì)、計(jì)算與繪圖能力，包括使用計(jì)算機(jī)部分繪圖；邏輯思維與形象思維相結(jié)合的文字及口頭表達(dá)能力。要對(duì)本專業(yè)在國(guó)內(nèi)外的發(fā)展現(xiàn)狀、技術(shù)水平有所了解。
本設(shè)計(jì)主要研究葵花脫粒的方法和工藝，對(duì)葵花脫粒機(jī)進(jìn)行整體結(jié)構(gòu)設(shè)計(jì)，并依據(jù)相關(guān)機(jī)械設(shè)計(jì)理論來(lái)完成零部件的設(shè)計(jì)。主要組成部件：動(dòng)力傳動(dòng)裝置，進(jìn)料出料部件，脫粒部件，篩分裝置等。
2 葵花脫粒機(jī)的總體結(jié)構(gòu)設(shè)計(jì)
葵花脫粒機(jī)主要組成部分：入料口、上蓋、脫粒軸體、底篩、機(jī)體、傳動(dòng)軸等部分組成。整體組成如圖所示
圖一 葵花脫粒機(jī)總體結(jié)構(gòu)
2.1入料部分
入料口與葵花脫粒機(jī)的上蓋部分相連，它是利用0.5厚的鐵板制成，入料部位與脫粒軸體部位相切，將葵花盤從入料口進(jìn)入，下滑到脫粒部位，即軸體和底篩之間，進(jìn)行脫粒。
圖二 入料口
2.2 脫粒部分
脫粒部分主要是由脫粒軸體、底篩、半圓型上蓋組成?？ūP在脫粒滾筒和底篩之間進(jìn)行脫粒，將已脫下的葵花粒從底篩的縫隙漏下，落到下滑板，由倉(cāng)口排出機(jī)體之外，空盤借助于滾筒上的螺旋排列的脫粒齒的螺旋推力和螺旋導(dǎo)向作用，由入料口的另一端（即出料口）排出機(jī)體之外。
圖三 葵花脫粒軸體
2.3 篩選部分
篩選部分主要是由底篩完成，無(wú)論是工作時(shí)還是安裝時(shí)，底篩是固定不動(dòng)的?？摿Ｖ螅賹⒖ㄗ呀?jīng)過(guò)底篩，從底篩的縫隙漏出，順著斜滑板滑出機(jī)體之外，目的是將葵花盤和葵花籽分開(kāi)。
圖四 脫粒機(jī)底篩
2.4 機(jī)體部分
機(jī)體是由左機(jī)架、右機(jī)架、出料口、下滑板及穩(wěn)定結(jié)實(shí)的主機(jī)梁組成，機(jī)體是葵花脫粒機(jī)的主要支撐，他承擔(dān)著脫粒機(jī)的主要重量和動(dòng)力、負(fù)載和力矩，因此它的設(shè)計(jì)是許強(qiáng)不許弱的部分。機(jī)架的兩部分要各自穩(wěn)定，而且相對(duì)固定，以便做到機(jī)械在運(yùn)轉(zhuǎn)過(guò)程中不會(huì)產(chǎn)生晃動(dòng)、歪斜，造成人身危險(xiǎn)，因此為了機(jī)架的堅(jiān)固，此葵花脫粒機(jī)的設(shè)計(jì)采用三毫米厚的角鐵制成。
圖五 機(jī)架
2.5 葵花脫粒機(jī)的總體設(shè)計(jì)
為了優(yōu)化葵花脫離機(jī)的機(jī)型和結(jié)構(gòu)設(shè)計(jì)，此葵花脫粒機(jī)采用馬18馬力—25馬力小四輪拖動(dòng)，葵花脫粒機(jī)和拖拉機(jī)為后三點(diǎn)懸掛式連接，將葵花脫粒機(jī)的兩個(gè)上牽引點(diǎn)，一個(gè)上牽引點(diǎn)分別和拖拉機(jī)的下?tīng)恳濉⑸蠣恳瓧U連接起來(lái)。調(diào)整上牽引拉桿使葵花脫粒機(jī)處于水平?？摿C(jī)從入料到脫粒到分離葵花籽和葵花盤，最后將葵花籽和葵花空盤排出機(jī)體之外，是葵花脫粒機(jī)一體完成的，它最大的優(yōu)點(diǎn)是在短時(shí)間內(nèi)可以完成幾個(gè)人的勞動(dòng)強(qiáng)度，從而提高了工作效率，節(jié)省了勞動(dòng)時(shí)間。此葵花脫粒機(jī)有這些優(yōu)點(diǎn)之外，還有安全性能高、效率高、堅(jiān)固耐用、結(jié)構(gòu)簡(jiǎn)單便于維修和保管。
3 葵花脫粒機(jī)的設(shè)計(jì)
有關(guān)葵花脫粒機(jī)5QK—400型的相關(guān)設(shè)計(jì)的參考數(shù)據(jù)：配套動(dòng)力18馬力—25馬力小四輪拖拉機(jī)，動(dòng)力傳動(dòng)軸轉(zhuǎn)速530—560r/min，運(yùn)輸間隙≥200，平均生產(chǎn)率≥350kg/h，最高生產(chǎn)率600kg/h，脫離滾筒直徑70cm，長(zhǎng)度154cm,在主軸上焊接有成規(guī)律性形狀的圓鋼，總共12個(gè)圓鋼齒條呈螺旋均勻安裝，以便葵花盤隨螺旋齒條的螺旋作用排出機(jī)體之外。
3.1 配套動(dòng)力的選擇
配套拖拉機(jī)的動(dòng)力P=14.7kw(20馬力),動(dòng)力輸出軸轉(zhuǎn)速為n=560r/min，由實(shí)際可知，拖拉機(jī)動(dòng)力輸出軸的功率為= (3-1)
拖拉機(jī)輸出轉(zhuǎn)矩：
T== (3-2)
式中：為拖拉機(jī)輸出功率，
為動(dòng)力輸出軸轉(zhuǎn)速
3.2 軸的設(shè)計(jì)
設(shè)計(jì)的軸長(zhǎng)為1850mm，軸分為4段。第一段軸與皮帶輪連接，其直徑為35mm；第二段軸用來(lái)裝軸承的，還需要設(shè)計(jì)一個(gè)軸肩，用來(lái)固定軸承：第三段是裝脫粒滾筒的，其直徑40mm。第四段軸裝軸承。
軸的材料：軸的材料主要是碳剛和合金剛。由于碳剛比合金剛價(jià)格便宜，對(duì)應(yīng)力集中的敏感性較低，同時(shí)也可以用熱處理或化學(xué)熱處理的辦法提高其耐磨性和抗疲勞強(qiáng)度，所以本設(shè)計(jì)采用45號(hào)剛作為軸的材料。調(diào)制處理。第三段軸軸表面淬火，增加其表面的耐磨性能。
3.3 軸的校核
經(jīng)過(guò)分析，軸的軸向力是主要的，因此，對(duì)軸進(jìn)行扭矩校核。
（1）軸的扭矩計(jì)算
由式（3-2）知拖拉機(jī)輸出轉(zhuǎn)矩為150.4NM
主軸輸入轉(zhuǎn)矩：
(3-3)
其中：為皮帶輪的傳動(dòng)效率根據(jù)設(shè)計(jì)指導(dǎo)書(shū)參考表1初選
為軸承的傳動(dòng)效率初選
為軸承的傳動(dòng)效率初選
根據(jù)要求，軸要滿足下列條件
（2）軸的強(qiáng)度條件：
式中：為軸的切應(yīng)力，Mpa；T為轉(zhuǎn)矩，N.mm；為抗扭截面系數(shù)，；為許用扭切應(yīng)力，MPa.
表3-1 常用材料的值和C值
軸的材料
Q235,20
35
45
40Cr，35SiMn
12-20
20-30
30-40
40-52
C
160-135
135-118
118-107
107-98
該軸的材料為45號(hào)鋼，則滿足強(qiáng)度條件，軸是安全的。
（3）軸的計(jì)算簡(jiǎn)圖
圖六 主軸受力圖
根據(jù)軸的計(jì)算簡(jiǎn)圖作出軸的彎矩圖
F為脫粒滾筒的平均阻力，F(xiàn)=380N
（其中 F為脫粒滾筒的平均阻力） (3-4)
經(jīng)計(jì)算F1=F2=190N
由此可知
=0 (3-5)
可得總彎扭矩圖：
圖七 總彎矩圖
圖八 總扭矩圖
由總彎矩圖可知軸承處是危險(xiǎn)截面。
按彎矩合成應(yīng)力校核軸的強(qiáng)度
進(jìn)行校核時(shí)，通常只校核軸上承受最大彎矩和扭矩的截面的強(qiáng)度。則由《機(jī)械設(shè)計(jì)基礎(chǔ)》P-245可得
其中，M為總彎矩；d為直徑
前已選定軸的材料為45鋼，調(diào)質(zhì)處理，由《機(jī)械設(shè)計(jì)基礎(chǔ)》P-246表14-3查得。
因?yàn)?
所以主軸符合強(qiáng)度要求
3.4 帶輪的設(shè)計(jì)
根據(jù)葵花脫粒機(jī)的具體傳動(dòng)要求，可選取拖拉機(jī)和主軸之間用V帶輪的傳動(dòng)方式傳動(dòng)，因?yàn)樵诿摿C(jī)的工作工程中，傳動(dòng)件V帶是一個(gè)撓性件，它賦有彈性，能緩和沖擊，吸收震動(dòng)，因而使脫粒機(jī)平穩(wěn)工作，噪音小等優(yōu)點(diǎn)。雖然在傳動(dòng)過(guò)程中V帶與帶輪之間存在著一些摩擦，導(dǎo)致兩者的相對(duì)滑動(dòng)，使傳動(dòng)比不精確但不會(huì)影響脫粒機(jī)的傳動(dòng)，因?yàn)榭摿C(jī)不需要精確的傳動(dòng)比，只要傳動(dòng)比比較精準(zhǔn)就可以滿足要求，而且，V帶的彈性滑動(dòng)對(duì)脫粒機(jī)的一些重要部件是一種過(guò)載保護(hù)，不會(huì)造成機(jī)體部件的嚴(yán)重?fù)p壞，還有V帶及帶輪的結(jié)構(gòu)簡(jiǎn)單、制造成本地、容易維修和保養(yǎng)、便于安裝，所以，在拖拉機(jī)和葵花脫粒機(jī)之間選用V帶輪的傳動(dòng)配合是很合理的。
表3-2 帶輪參數(shù)
槽型
直徑
孔徑基準(zhǔn)
L
槽數(shù)
Z
35
100
70
70 104 4
帶輪材料選灰鑄鐵HT200.
3.5 軸承的選擇
根據(jù)軸受力和軸徑的不同，本設(shè)計(jì)選用的軸承是：深溝球軸承
已知此處軸徑為30mm，所以選內(nèi)徑為30mm的軸承，在機(jī)械設(shè)計(jì)手冊(cè)中選擇深溝球軸承；查表6-1，選擇型號(hào)為6007 GB/T276—94的軸承。另一處已知軸徑為30mm，所以選內(nèi)徑也為30mm的軸承，選擇型號(hào)也為6007 GB/T276—94的軸承。所選的軸承基本參數(shù)如下：[10]
軸承外徑： b=30mm；D=62mm；B=14mm
基本額定動(dòng)載荷：C=16.2KN
基本額定靜載荷：C=10.5KN
4 葵花脫粒機(jī)上的標(biāo)準(zhǔn)件的選擇
4.1 葵花脫粒機(jī)上的螺栓的選擇
應(yīng)用在葵花脫粒機(jī)上的螺栓是機(jī)械設(shè)計(jì)的標(biāo)準(zhǔn)件，螺栓的選擇可以根據(jù)《機(jī)械設(shè)計(jì)手冊(cè)》查取。在本脫粒機(jī)上選擇的螺栓為：公稱直徑為M8，長(zhǎng)度為八厘米和五厘米，葵花脫粒機(jī)應(yīng)用的螺栓是起連接作用，在機(jī)體的上蓋和機(jī)架應(yīng)用螺栓連接，應(yīng)用公稱直徑為M8 的螺栓，就可以滿足葵花脫粒機(jī)的動(dòng)力需要。
4.2 鍵的選擇
（1）鍵的尺寸、類型的確定
一般8級(jí)精度以上齒輪有定心精度要求，應(yīng)選用平鍵。一般圓頭普通平鍵應(yīng)用最廣。
根據(jù)d=35mm，從《機(jī)械設(shè)計(jì)手冊(cè)》P-53表4-1中查得鍵的截面尺寸為：寬度b=10mm，高度h=8mm。由輪轂寬度并參考鍵的長(zhǎng)度系列，取鍵長(zhǎng)L=45mm。
（2） 校核鍵聯(lián)接的強(qiáng)度
鍵、軸和輪轂的材料都是鋼，由《機(jī)械設(shè)計(jì)課程設(shè)計(jì)手冊(cè)》P-54表4-2查得許用擠壓應(yīng)力，取其平均值，。
鍵的工作長(zhǎng)度l=L-b=35mm。
鍵與輪轂鍵槽的接觸高度k=0.5h=4mm。
由《機(jī)械設(shè)計(jì)基礎(chǔ)》P-158式（10--26）可得
故可見(jiàn)鍵合適安全。
5 葵花脫粒機(jī)安全操作規(guī)程注意事項(xiàng)
葵花脫粒機(jī)是解決葵花脫粒的問(wèn)題，起目的是降低勞動(dòng)者的勞動(dòng)強(qiáng)度，提高工作效率，節(jié)省工作時(shí)間，同時(shí)在利用葵花脫粒機(jī)時(shí)，除了提高勞動(dòng)效率之外更應(yīng)該注意安全問(wèn)題，注意到葵花脫粒機(jī)的正確使用，可以避免應(yīng)用葵花脫粒機(jī)時(shí)造成人員傷害和脫粒機(jī)事故的發(fā)生。下面略述一些常見(jiàn)的事故和原因。
5.1 超速運(yùn)轉(zhuǎn),機(jī)械“爆炸”
葵花脫粒機(jī)的主要工作部件，如脫粒軸體、底篩，軸等，這些零部件所能承受的力是有一定的限度的，當(dāng)脫粒軸體高速旋轉(zhuǎn)時(shí)，便會(huì)產(chǎn)生很大的離心力，如果脫粒軸體的轉(zhuǎn)速超過(guò)一定的范圍，和滾動(dòng)軸承的老化及拖拉機(jī)的功率較高時(shí)，就有可能使運(yùn)動(dòng)的主軸和主軸上的齒條滾筒與機(jī)體相分離，或和葵花脫粒機(jī)的上蓋相撞，或和底篩相撞，可以產(chǎn)生很大的沖擊力，這種急速的沖擊會(huì)造成葵花脫粒機(jī)的爆炸，會(huì)危害到工作人員的身體安全，為了避免這種事故的發(fā)生，應(yīng)當(dāng)急時(shí)的更換機(jī)械重要部位零件，定時(shí)擰緊緊固螺栓，一提高工作安全系數(shù)。
5.2 禁止過(guò)疲勞或酒后操作
葵花脫粒機(jī)的動(dòng)力很大，雖然用機(jī)架和上蓋將齒條滾筒及主軸罩住，加在機(jī)體之間，起到安全作用，而且葵花脫粒機(jī)的入料口的設(shè)計(jì)也很合理，但是也同樣禁止過(guò)疲勞或酒后操作，主要是由于過(guò)疲勞或酒后造作人員的大腦很可能不由造作人員的控制，造成操作人員將身體的某個(gè)部位伸入機(jī)械，與主軸或齒條滾筒相接觸，由于釘齒滾筒的高速旋轉(zhuǎn)，會(huì)使操作人員的錯(cuò)誤操作行為造成不必要的傷害，危害到勞動(dòng)者的安全。
因此，為了勞動(dòng)者的安全，應(yīng)避免過(guò)疲勞或酒后操作。
5.3 注意事項(xiàng)
1.初次使用前，應(yīng)檢查機(jī)器上的安全標(biāo)志、明確使用說(shuō)明書(shū)中安全操作規(guī)程和危險(xiǎn)部位安全標(biāo)志提示的內(nèi)容。
2.使用機(jī)器前，應(yīng)檢查機(jī)器上的安全標(biāo)志，操作指示牌和產(chǎn)品有無(wú)殘損，殘損時(shí)應(yīng)及時(shí)補(bǔ)全。
3.每個(gè)作業(yè)季節(jié)前，應(yīng)檢查脫離滾筒上的工作部件有無(wú)裂紋和變形。更換部件時(shí)，應(yīng)按使用說(shuō)明書(shū)的要求或有經(jīng)驗(yàn)的維修人員的知道下進(jìn)行。
4.妨礙操作和影響機(jī)器安全的部位不應(yīng)該裝。
5.更換動(dòng)力時(shí)，必須保證主軸轉(zhuǎn)速在使用說(shuō)明中或機(jī)器明示標(biāo)識(shí)所規(guī)定的范圍之內(nèi)，外露的傳動(dòng)部位必須有防護(hù)裝置。
7.機(jī)器作業(yè)前應(yīng)進(jìn)行試運(yùn)轉(zhuǎn)，試運(yùn)轉(zhuǎn)應(yīng)無(wú)碰擦、無(wú)異常聲響和震動(dòng)。滾動(dòng)旋向應(yīng)正確，轉(zhuǎn)速應(yīng)符合作用說(shuō)明書(shū)中的規(guī)定，嚴(yán)禁超速工作。
8.啟動(dòng)機(jī)器前應(yīng)給出信號(hào)，確認(rèn)機(jī)器旁邊沒(méi)有人時(shí)可起動(dòng)。
9.嚴(yán)禁酒后、孕婦、未成年人操作，操作人員工作時(shí)應(yīng)扎緊袖口，留長(zhǎng)發(fā)時(shí)應(yīng)戴防護(hù)帽。
10.作業(yè)時(shí)緊將手伸入喂料口，出籽口以及其他危險(xiǎn)運(yùn)動(dòng)部件內(nèi)。
11.排料口的正前方嚴(yán)禁站人。
12.作業(yè)時(shí)嚴(yán)禁將石頭、木頭、金屬等堅(jiān)硬物喂入機(jī)內(nèi)。
13.作業(yè)時(shí)候發(fā)現(xiàn)堵塞其他異常應(yīng)立即停機(jī)，切斷動(dòng)力后方可進(jìn)行清理檢查。
14.軸承座和其他運(yùn)動(dòng)部件上的螺栓不得有松動(dòng)現(xiàn)象，并按使用說(shuō)明書(shū)的要求定期檢查。
6 葵花脫粒機(jī)的安裝、調(diào)整和使用
6.1 葵花脫粒機(jī)與拖拉機(jī)的連接
葵花脫粒機(jī)和拖拉機(jī)為后三點(diǎn)懸掛式連接，將葵花脫粒機(jī)的兩個(gè)上牽引點(diǎn)，一個(gè)上牽引點(diǎn)分別和拖拉機(jī)的下?tīng)恳濉⑸蠣恳瓧U連接起來(lái)。調(diào)整拖拉機(jī)下?tīng)恳謇準(zhǔn)蛊浣?jīng)緊，然后調(diào)整上牽引使葵花脫粒機(jī)處于水平。
當(dāng)和有氣泵皮帶小四輪拖拉機(jī)配套時(shí)，可將皮帶輪拆下，換上與葵花脫粒機(jī)要求相適應(yīng)的皮帶輪，掛接上相應(yīng)的皮帶輪即可。
當(dāng)和無(wú)氣泵皮帶輪的小四輪拖拉機(jī)配套時(shí)，把拖拉機(jī)皮帶防護(hù)罩卸下，將離全器三角皮帶卸下兩根，掛上隨機(jī)所配兩根皮帶。
6.2 調(diào)整
葵花脫粒機(jī)和拖拉機(jī)連接好以后，應(yīng)檢查皮帶是否平直，不正時(shí)請(qǐng)予以調(diào)整，以運(yùn)轉(zhuǎn)時(shí)不掉皮帶為佳，傳動(dòng)皮帶張緊度要調(diào)整適當(dāng)，可通過(guò)張緊輪在機(jī)架上的不對(duì)位置來(lái)調(diào)整，調(diào)整合適后，緊固各個(gè)螺栓。
6.3 試運(yùn)轉(zhuǎn)
機(jī)組連接好以后，分離離合器，啟動(dòng)柴油機(jī)，以小油門把機(jī)組帶動(dòng)起來(lái)，使機(jī)組空轉(zhuǎn)30秒，檢查有無(wú)摩擦及碰撞等異常聲音。
6.4 田間工作
在田間工作時(shí)，應(yīng)在葵花脫粒機(jī)的支腳下墊上長(zhǎng)木板，以防機(jī)器下陷。盡可能使機(jī)器保持水平。在喂葵花時(shí)，要均勻喂入，不可整筐、整袋喂入，嚴(yán)謹(jǐn)將石子、鐵器等異物喂入機(jī)內(nèi)，防止打壞機(jī)器。發(fā)現(xiàn)有堵塞現(xiàn)象時(shí)，立即進(jìn)行清理。
清理排除故障時(shí)，首先將拖拉機(jī)熄火，嚴(yán)謹(jǐn)拖拉機(jī)未熄火時(shí)排除故障。
7 葵花脫粒機(jī)的保養(yǎng)與維修
7.1使用中的保養(yǎng)
1.每班作業(yè)完畢，及時(shí)清除機(jī)具上的雜物，以防銹蝕。
2.每班工作前，檢查各工作部件有無(wú)變形或損壞若發(fā)現(xiàn)問(wèn)題及時(shí)予以校正或更換。
3.旋轉(zhuǎn)的部件，每班必須加注潤(rùn)滑油、脂一次。
4.每工作3―5個(gè)班次，打開(kāi)機(jī)器檢查，清除雜物。
5.長(zhǎng)距離運(yùn)輸前和每班作業(yè)后都應(yīng)全面檢查各緊固件的連接情況，如有松動(dòng)，立即予以緊固。
7.2入庫(kù)停放前的保養(yǎng)
1.徹底清除機(jī)具表面及里面的雜物，并進(jìn)行涂油防銹處理。
2.檢查機(jī)具的磨損、變形、損壞、缺件情況及軸承、軸套的間隙，及時(shí)調(diào)整、換件，或及時(shí)采購(gòu)配件，使來(lái)年的工作有保證。
3.機(jī)具停放在庫(kù)房?jī)?nèi)，防日曬，防雨淋，最好罩上蓬蓋。
總結(jié)
本設(shè)計(jì)的研究就是為了解決農(nóng)民葵花脫粒難的問(wèn)題，使脫粒機(jī)能在農(nóng)業(yè)方面有更大的作用。但由于本設(shè)計(jì)在國(guó)內(nèi)外研究還不夠成熟，所以在數(shù)據(jù)上還不能完全確定。例如葵花盤的的大小，葵花籽顆粒與葵花盤黏合的程度，在葵花水分達(dá)到什么程度時(shí)最易分離。
經(jīng)過(guò)計(jì)算和理論分析，箱體滿足強(qiáng)度要求，能夠承載各部件的重量和支撐各部件完成預(yù)定的工作要求。軸的設(shè)計(jì)計(jì)算，經(jīng)過(guò)理論的校核，滿足強(qiáng)度和剛度要求。軸承的選擇符合壽命要求。V帶輪的選擇，符合轉(zhuǎn)速和功率的要求。鍵的選用符合要求。此機(jī)型可以實(shí)現(xiàn)對(duì)葵花脫粒的要求。
畢業(yè)設(shè)計(jì)是高等學(xué)校本科教學(xué)計(jì)劃中非常重要的組成部分，是對(duì)學(xué)生在大學(xué)期間所學(xué)的專業(yè)基礎(chǔ)知識(shí)、研究能力、自學(xué)能力、創(chuàng)新能力及其他綜合能力的檢驗(yàn)，是教學(xué)計(jì)劃中最后一個(gè)綜合性實(shí)踐教學(xué)環(huán)節(jié)，也是高校開(kāi)展綜合素質(zhì)教育和創(chuàng)新能力培養(yǎng)的重要途徑。鞏固和加強(qiáng)學(xué)生對(duì)多元學(xué)科理論、基礎(chǔ)知識(shí)與技能的綜合應(yīng)用能力的訓(xùn)練，培養(yǎng)學(xué)生創(chuàng)新意識(shí)、創(chuàng)新能力和科學(xué)研究能力，培養(yǎng)其嚴(yán)謹(jǐn)、求實(shí)的治學(xué)態(tài)度和刻苦鉆研、勇于探索的精神。
致 謝
首先衷心感謝我的指導(dǎo)老師萬(wàn)暢！本設(shè)計(jì)是在萬(wàn)暢老師的悉心指導(dǎo)下完成的。他無(wú)論是在資料的整理，還是在設(shè)計(jì)的畫(huà)圖等各個(gè)方面都給予了我大量的指導(dǎo)和幫助，在他的精心指導(dǎo)下，才使得我的設(shè)計(jì)一步一步的有序的完成，同時(shí)也學(xué)到了許多書(shū)本上學(xué)不到的知識(shí)，受益匪淺，特致以深深的感謝。同時(shí)也要感謝學(xué)科組每一位老師，不僅在“授業(yè)、傳道、解惑”方面給予了精心培養(yǎng)和指導(dǎo)，也給我提供了充足完備的條件和寶貴的學(xué)習(xí)交流機(jī)會(huì)，而且在生活方面還給予我極大的關(guān)懷，學(xué)生深表謝意。
再次,感謝我的同學(xué)們,在畢業(yè)設(shè)計(jì)過(guò)程中得到了他們無(wú)私的幫助，以及許多啟發(fā)性的指導(dǎo)和建議。在此向所有支持、關(guān)心、幫助我的人表示由衷的感謝!祝他們永遠(yuǎn)健康、幸福!
值此論文完成之際，謹(jǐn)向所有關(guān)心、支持和幫助我的老師、同學(xué)和朋友表示最衷心的感謝！
參考文獻(xiàn)
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7. 肖旭霖.食品加工技術(shù)裝備[M]，北京：中國(guó)輕工業(yè)出版社，2007
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10. 吳宗澤、羅圣國(guó).機(jī)械設(shè)計(jì)課程設(shè)計(jì)手冊(cè)（第三版）[M]，北京：高等教育出版社，2007
11. 楊可楨、程光蘊(yùn)、李忠生.機(jī)械設(shè)計(jì)基礎(chǔ)（第五版）[M]，北京：高等教育出版社，2006
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systems. assessing the example of three tractors of the same category, which are exploited in climatic and soil conditions 1. Introduction for agricultural agricultural recognized careful technical, predicting ofcropproduction.Nowadays,theexistingmathematicaloptimiza- tion methods, supported by the high-performance computers, can efficiently resolve the optimization problems (Dette Duffy et al., 1994; Mileusnic, 2007; etc.). The formation of an optimal technical system in order to produce cheaper food, highly impacted reliability of tractors, its maintainability, and the functionality of the system. rounding conditions. Although in the same spirit, some authors have defined effectiveness somewhat differently. In (Ebramhimipour maintainabilityascapacityofthe systemforpreventionandfindingfailuresanddamages,forrenewing operating ability and functionality through technical attending and repairs; and functionality as the degree of fulfilling the functional requirements, namely the adjustment to environment, or more pre- cisely to the conditions in which the system operates. In the case of monitoring reliability and maintainability it is common to monitor the time picture of state (Fig. 1) according to their working conditions is obtained. The model can be used as cri- teria for decision making related to any procedure in purchasing, operation or maintenance of the system, for prediction of repair and maintenance costs. Quality and functionality of the proposed model is shown in effectiveness determination of agricultural machinery, precisely tractors. R. Miodragovic et al./Expert Systems with Applications 39 (2012) 89408946 8941 which the functions of reliability and maintainability can be deter- mined, as well as the mean time in operation and the mean time in failure. The main problem that occurs in forming the time picture of state is data monitoring and recording. In real conditions the ma- chines should be connected to information system which would precisely record each failure, duration and procedure of repair. This is usually expensive and improvised monitoring of the machine performance, namely of its shut downs, is imprecise. Moreover, statistical data processing provided by the time picture of the state requires that all machines work under equal conditions, which is difficult to achieve. As for the functionality of the technical system, there is no common way for its measuring and quantification. This is the reason why in this paper, in order to assess the effectiveness, expertise judgments of the employed in the working process of the analyzed machines will be used. Application of expertise judgments has been largely used in literature, primarily for data processing and the assessment of the technical systems in terms of: risk (Li Wang, Yang, Tanasijevic, Ivezic, Ignjatovic, Zadeh, 1996). Application of fuzzy sets today represents one of the most frequently used tools for solving the problems in various areas of optimization (Huang, Gu, Liebowitz, 1988) in general is also used for solving the optimizations problems from area of agro machinery. In article (Rohani, Abbaspour-Fard, and fuzzy composition of men- tioned indicators into one synthesized. Fuzzy proposition is pro- cedure for representing the statement that includes linguistic variables based on available information about considered techni- cal system. In that sense it is necessary to define the names of lin- guistic variables that represent different grades of effectiveness of considered technical system and define the fuzzy sets that describe the mentioned variables. Composition is a model that provides structure of indicators influences to the effectiveness performance. 2.1. Fuzzy model of problem solving The first step in the creation of fuzzy model for effectiveness (E) assessment is defining linguistic variables related to itself and to reliability (R), maintainability (M) and functionality (F). Regarding number of linguistic variables, it can be found that seven is the maximal number of rationally recognizable expressions that hu- man can simultaneously identify (Wang et al., 1995). However, for identification of considered characteristics even the smaller number of variables can be useful because flexibility of fuzzy sets to include transition phenomena as experts judgments commonly is (Ivezic et al., 2008). According to the above, five linguistic vari- ables for representing effectiveness performances are included: poor, adequate, average, good and excellent. Form of these linguis- tic variables is given as appropriate triangular fuzzy sets (Klir .;l 5 R ; l M l 1 M ; .;l 5 M ; l F l 1 F ; .;l 5 F 1 In the next step, maxmin composition is performed on them. Max min composition, also called pessimistic, is often used in fuzzy alge- bra as a synthesis model (Ivezic et al., 2008; Tanasijevic et al., 2011; Wang et al., 1995; Wang 2000). The idea is to make overall assess- ment (E) equal to the partial virtual representative assessment. This assessment is identified as the best possible one between the worst partial grades expected (R, M or F). It can be concluded that all elements of (R, M and F) that make the E have equal influence on E, so that maxmin composition will be used, which in parallel way treats the partial ones onto the h time of planned shut down due to preventive maintenance. 1995) and OR R M F If we tions that is (according to Fig. 2): with 39 (2012) 89408946 Further, for each outcome its values are calculated (X c ). The outcome which would suit the combination c, it would be calcu- lated following the equations: X c P R;M;E j hi c 3 3 Finally, all of these outcomes are treated with maxmin composi- tion, as follows: (i) For each outcome search for the MINimum value of l R,M,F in vector E c (2). The minimum which would suit the combina- tion o, it would be calculated following the equations: MIN 0 minfl j1;.;5 R ;l j1;.;5 M .;l j1;.;5 F g;for all o 1toO 4 (ii) Outcomes are grouped according to their values X c (3), namely the size of j. (iii) Find the MAXimum between previously identified mini- mums (i) for each group (ii) of outcomes. The maximum which would suit value of j, would be calculated following the equations: MAX j maxfMIN o g; for every j 5 E assessment of technical system is obtained in the form: l E This expression (Fig. 2 tion of to fuzzy cedure (d) between the E which d i E j ;H take into account only values if l j1;.;5 R;M;F 0, we get combina- are named outcomes (o =1toO, where O # C). in the process of synthesis, are also used. Precisely, if we look at three partial indicators, namely their membership function (1), it is possible to make C = j 3 =5 3 combina- tions of their membership functions. Each of these combinations represents one possible synthesis effectiveness assessment (E). E l j1;.;5 ;l j1;.;5 ; .;l j1;2;.5 hi ; for all c 1toC 2 maxmin compositions which by using operators AND provide an advantage to certain elements over the others synthetic indicator. In literature (Ivezic et al., 2008; Wang et al., Fig. 2. Effectiveness fuzzy sets. 8942 R. Miodragovic et al./Expert Systems MAX j1 ; .;MAX j5 l 1 E ; .;l 5 E 6 (6) is necessary to map back to the E fuzzy sets ). Best-fit (Wang et al., 1995), method is used for transforma- E description (6) to form that defines grade of membership sets: poor, adequate, average, good and excellent. This pro- is recognized as identification. Best-fit method uses distance E obtained by maxmin composition (6) and each of expressions (according to Fig. 2), to represent the degree to E is confirmed to each of fuzzy sets of effectiveness (Fig. 2). i X 5 j1 l j E C0l j H j 2 v u u t ; j 1; .;5;H i fexcellent;goodaverage;adequate;poorg7 E i fb i1 ;poor;b i2 ;adequate;b i3 ;good; b i4 ;average;b i5 ;excellentg 10 3. An illustrative example As an illustrative example of evaluation of agriculture machin- ery effectiveness, the comparative analysis of three tractors A 1 B 2 , and C 2 is given in this article. In tractor A a 7.146 l engine LO4V TCD 2013 is installed. Thanks to the reserves of torque from 35%, the tractor is able to meet all the requirements expected in the worst performing farming oper- ations in agriculture. Total tractor mass is 16,000 kg. According to OECD (CODE II) report maximum power measured at the PTO shaft is 243 kW at 2200 rpm with specific fuel consumption of 198 g/kW h (ECE-R24). Maximum engine torque is 1482 Nm at en- gine regime of 1450 rpm. Transmission gear is vario continious transmision. Linkage mechanism is a Category II/III with lifting force of 11,800 daN. In tractors B 2 and C 2 8.134 l engine 6081HRW37 JD is installed, with reserve torque of 40%, and this tractor was able to meet all the requirements expected in the worst performance of the farming operations in agriculture. Total tractor weight is 14,000 kg. Accord- ing to OECD (CODE II) report maximum power measured at the PTO shaft is 217 kW at 2002 rpm with specific fuel consumption of 193 g/kW h (ECE-R24). Maximum torque is 1320 Nm at engine revs of 1400 rpm. Transmission is AutoPower. Linkage mechanism is a Category II/III with lifting force of 10,790 daN. Both models have electronically controlled tractor engine and fuel supply system that meets the regulations on emissions. From the submitted technical characteristics of the tractor A, B and C it is seen that all three tractors are fully functional for l exc. = (0,0,0,0.25,1); l good = (0,0,0.25,1,0.25); l aver. = (0,0.25,1,0.25,0); l adeq. = (0.25,1,0.25,0,0); l poor = (1,0.25,0,0,0). The closer l E (6) is to the ith linguistic variable, the smaller d i is. Distance d i is equal to zero, if l E (6) is just the same as the ith expression in terms of the membership functions. In such a case, E should not be evaluated to other expressions at all, due to the exclusiveness of these expressions. Suppose d imin (i =1,.,5) is the smallest among the obtained distances for E j and leta 1 ,.,a 5 represent the reciprocals of the rel- ative distances (which is calculated as the ratio between corres- ponding distance d i (7) and the mentioned values d imin ). Then, a i can be defined as follows: a i 1 d i =d imin ; i 1; .;5 8 If d i = 0 it follows that a i = 1 and the others are equal to zero. Then, a i can be normalized by: b i a j P 5 m1 a im ; i 1; .;5 X 5 i1 b i 1 9 Each b i represents the extent to which E belongs to the ith defined E expressions. It can be noted that if E i completely belongs to the ith expression then b i is equal to 1 and the others are equal to 0. Thus b j could be viewed as a degree of confidence that E i belongs to the ith E expressions. Final expression for E performance at the level of tech- nical system, have been obtained in the form (10) where Applications 1 Tractor Fendt Vario 936. 2 Tractor John Deere 8520. performing difficult operations for different technologies of agri- cultural production. Tractors B and C have the same technical char- acteristics, and practice is the same type and model, except that the tractor B entered into operation in May 2007, a tractor C in June 2007. A tractor on the experimental farm, which is the technical documentation for the base model, comes into operation in July 2009. The main task of maintaining agricultural techniques is to provide functionality and reliability of machines. Maintenance of all three tractors is done by machine shop owned by the user up- grade option. Ten engineers (analysts) working on maintenance and opera- tion of tractors were interviewed. Their evaluation of R, D and F are given in Table 1. First, the effectiveness of tractor A is calculated. It can be seen that the reliability was assessed as excellent by six out of ten ana- lysts (6/10 = 0.6), as average by three (0.3) and as good by one (0.1). In this way the assessment R is obtained in the form (11): R 0:6=exc; 0:3=good; 0:1=aver; 0=adeq; 0=poor11 In the same way the assessments for M and F are obtained: M 0:4=exc; 0:4=good; 0:2=aver; 0=adeq; 0=poor F 0:5=exc; 0:5=good; 0=aver; 0=adeq; 0=poor In the next step, these assessments are mapped on fuzzy sets (Fig. 1) in order to obtain assessment in the form (1). For example, Reliabil- ity in this example is determined as (11), where it is to linguistic variable excellent joined weight 0.6. Thereby, fuzzy set excellent is defined as: R exc = (1/0, 2/0, 3/0, 4/0.25, 5/1.0) (according to Fig. 1). In this way the specific values of fuzzy set excellent R exc0.6 = (1/(0 C2 0.6), 2/(0 C2 0.6), 3/(0 C2 0.6), 4/(0.25 C2 0.6), 5/(1.0 C2 0.6) are obtained. The remaining four linguistic variables are treated in the same way. In the end for each j =1,.,5 specific membership functions (last row, Table 2) are added into the final fuzzy form (1) of tractor A reliability: l RA 0;0:025;0:175;0:475;0:675 In the same way, based on the questionnaire (Table 1) values for maintainability and functionality are obtained: l MA 0;0:05;0:3;0:55;0:5; l FA 0;0;0:125;0:625;0:62512 These fuzzificated assessments (11) and (12) are necessary to syn- thesize into assessment of effectiveness, using maxmin logics. In this case it is possible to make C =5 3 = 125 combinations, out of which the 48 outcomes. First outcome would be for combination 2-2-3: E 2-2-3 = 0.025,0.05,0.125, where is X 2-2-3 = (2 + 2 + 3)/3 = 2 (rounded as integer). Smallest value among the membership func- tions of this outcome is 0.025. Other outcomes and corresponding values of X c are shown in Table 3. All these outcomes can be grouped around sizes X = 2, 3, 4 and 5. For example, for outcome X = 5 it can be written: E 4C05C05 0:475;0:5;0:625C138;E 5C04C05 0:675;0:55;0:625C138;E 5C05C04 0:675;0:5;0:625C138;E 5C05C05 0:675;0:5;0:625C138 Further, for each of them, minimum between membership function is sought: Table 1 Results of questionnaire. Average x x xx x xx x R. Miodragovic et al./Expert Systems with Applications 39 (2012) 89408946 8943 Analyst Linguistic variables Tractor A Tractor B Excellent Good Average Adequate Poor Excellent Good 1R x x Mx x Fxxx 2R x Mx x Fx 3R x x Mx Fx 4R x x Mx Fx x 5R x x Mx Fxxx 6R x x Mx Fx x 7R x Mx Fx 8R x x Mx x Fx x 9R x x Mx x Fx x 10 R x x Mx x Fx x Tractor C Adequate Poor Excellent Good Average Adequate Poor x x x x x x x x x x x xx x x x x x x x x x with Table 2 Calculation of specific values of fuzzy sets. 12345 0.6/exc. 0 C2 0.6 0 C2 0.6 0 C2 0.6 0.25 C2 0.6 1.0 C2 0.6 0.3/good 0 C2 0.3 0 C2 0.3 0.25 C2 0.3 1.0 C2 0.3 0.25 C2 0.3 8944 R. Miodragovic et al./Expert Systems MINE 4C05C05 minf0:475;0:5;0:625g0:475;MINE 5C04C05 0:55;MINE 5C05C04 0:5;MINE 5C05C05 0:5 Between these minimums, in the end it seeks maximum: MAXX d5 maxf0:475;0:55;0:5;0:5g0:55 Also for other values: X: MAX X =2 = 0.025; MAX X =3 = 0.175; MAX X =4 = 0.55 (Table 1.) 0.1/aver. 0 C2 0.1 0.25 C2 0.1 1.0 C2 0.1 0.25 C2 0.1 0 C2 0.1 0/adeq. 0.25 C2 0 1.0 C2 0 0.25 C2 00C2 00C2 0 0/poor 1.0 C2 0 0.25 C2 00C2 C2 C2 0 P R 0 0.025 0.175 0.475 0.675 Table 3 Structure of MAXMIN composition. Comb. X l MIN 2345 2-2-3 2 0.025,0.05,0.125 0.025 2-2-4 3 0.025,0.05,0.625 0.025 2-2-5 3 0.025,0.05,0.625 0.025 2-3-3 3 0.025,0.3,0.125 0.025 2-3-4 3 0.025,0.3,0.625 0.025 2-3-5 3 0.025,0.3,0.625 0.025 2-4-3 3 0.025,0.55,0.125 0.025 2-4-4 3 0.025,0.55,0.625 0.025 2-4-5 4 0.025,0.55,0.625 0.025 2-5-3 3 0.025,0.5,0.125 0.025 2-5-4 4 0.025,0.5,0.625 0.025 2-5-5 4 0.025,0.5,0.625 0.025 3-2-3 3 0.175,0.05,0.125 0.05 3-2-4 3 0.175,0.05,0.625 0.05 3-2-5 3 0.175,0.05,0.625 0.05 3-3-3 3 0.175,0.3,0.125 0.125 3-3-4 3 0.175,0.3,0.625 0.175 3-3-5 4 0.175,0.3,0.625 0 0.175 3-4-3 3 0.175,0.55,0.125 0.125 3-4-4 4 0.175,0.55,0.625 0.175 3-4-5 4 0.175,0.55,0.625 0.175 3-5-3 4 0.175,0.5,0.125 0.125 3-5-4 4 0.175,0.5,0.625 0.175 3-5-5 4 0.175,0.5,0.625 0.175 4-2-3 3 0.475,0.05,0.125 0.05 4-2-4 3 0.475,0.05,0.625 0.05 4-2-5 4 0.475,0.05,0.625 0.05 4-3-3 3 0.475,0.3,0.125 0.125 4-3-4 4 0.475,0.3,0.625 0.3 4-3-5 4 0.475,0.3,0.625 0.3 4-4-3 4 0.475,0.55,0.125 0.125 4-4-4 4 0.475,0.55,0.625 0.475 4-4-5 4 0.475,0.55,0.625 0.475 4-5-3 4 0.475,0.5,0.125 0.125 4-5-4 4 0.475,0.5,0.625 0.475 4-5-5 5 0.475,0.5,0.625 0.475 5-2-3 3 0.675,0.05,0.125 0.05 5-2-4 4 0.675,0.05,0.625 0.05 5-2-5 4 0.675,0.05,0.625 0.05 5-3-3 4 0.675,0.3,0.125 0.125 5-3-4 4 0.675,0.3,0.625 0.3 5-3-5 4 0.675,0.3,0.625 0.3 5-4-3 4 0.675,0.55,0.125 0.125 5-4-4 4 0.675,0.55,0.625 0.55 5-4-5 5 0.675,0.55,0.625 0.55 5-5-3 4 0.675,0.5,0.125 0.125 5-5-4 5 0.675,0.5,0.625 0.5 5-5-5 5 0.675,0.5,0.625 0.5 MAX 0.025 0.175 0.55 0.55 Finally, we get expression for membership function of effective- ness of tractor A: l EA 0;0:025;0:175;0:55;0:55 Best-fit method (79) and proposed E fuzzy set (Fig. 1) give the final effectiveness assessment for the tractor A: d 1 E;exc X 5 j1 l j E C0l j exc 2 v u u t 0C00 2 0:025C00 2 0:175C00 2 0:55C00:25 2 0:55C01 2 q 0:56899 where is : l E 0;0:025;0:175;0:55;0:55 l exc 0;0;0;0:25;1 For other fuzzy sets: d 2 (E, good) = 0.54658, d 3 (E, aver) = 1.06007, d 4 (E, adeq) = 1.27426, d 5 (E, poor) = 1.29856. for d min d 2 : a 1 1 d 1 =d 2 1 0:56899=0:54658 0:96061; a 2 1:00000;a 3 0:51561;a 4 0:42894;a 5 0:42091: b 1 a 1 P 5 i1 a i 0:96901 0:96901 1 0:51561 0:42894 0:42091 0:28881; b 2 0:30065;b 3 0:15502;b 4 0:12896;b 5 0:12655: Finally, we get the assessment of effectiveness of tractor A, in form (10): E A =(b 1 , excellent), (b 2 , good), (b 3 , average), (b 4 , ade- quate), (b 5 , poor) = (0.28881, excellent), (0.30065, good), (0.15502, average), (0.12896, adequate), (0.12655, poor) In the same way, we get the assessments for other two tractors B and C: E B = (0.23793, excellent), (0.27538, good), (0.20635, aver- age), (0.14693, adequate), (0.13342, poor) E C = (0.17507, excellent), (0.25092, good), (0.25468, aver- age), (0.17633, adequate), (0.14300, poor). Tractor A is in great extent of 0.30065 (in relation to 30 %) as- sessed as good, tractor B in great extent of 0.27538 (27.5%) as- Applications 39 (2012) 89408946 sessed as good, while tractor C is in great extent of 0.25468 (25.5%) assessed as average. It can be concluded that C is the worst, while tractor A is only somewhat better than B, especially if we see with that A is assessed as excellent in the extent of 28.8% while B in the extent of 23.8%. Effectiveness of analyzed tractors can be presented as in Fig. 3., where it can be more clearly seen that tractor A has the biggest effectiveness. If this assessment (E A , E B , E C ) is defuzzificated by center of mass point calculation Z (Bowles if calculated on 10,000 moto-hours, Fig. 3. Relationship of effectiveness of observed tractors. R. Miodragovic et al./Expert Systems it would spend in work 9244 moto-hours. As of the tractor B, out of 10,004 available moto-hours, it spent 9069 moto-hours in work, and tractor C out of 9981 available moto-hours spent 9045 in work. The experiment showed that the more reliable and efficient tractors are the less frequent are delays. In part, this initial advan- tage wiped out worse logistics of delivery of spare parts when it comes to tractor A. in 1100 moto-hours work of the tractor, due to poor logistics in maintaining hoped to eight working days, and it greatly influenced the decline in benefits of maintainability of a given tractor and thus the decline in total exploitation of the same efficiency (Internal technical documentation PKB). 4. Conclusion This paper presents a model for effectiveness assessment of technical systems, precisely agricultural machinery, based on fuzzy sets theory. Effectiveness performance has been adopted as overall indicator of systems quality of service, i.e. as entire measure of technical system availability. Reliability, maintainability and func- tionality performances have been recognized as effectiveness parameters or indicators. Linguistic form can be appointed as the References Bowles, J. B., & Pelaez, C. E. (1995). Fuzzy logic prioritization of failures in a system failure mode, effects and criticality analysis. Reliability Engineering and System Safety, 50(2), 203213. Cai, K. Y. (1996).
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