電動旋耕機設(shè)計

電動旋耕機設(shè)計,電動旋耕機設(shè)計,電動,旋耕機,設(shè)計 中期檢查表學 部： 學生姓名臧龍學 號年級專業(yè)及班級指導教師及職稱畢業(yè)論文（設(shè)計）題目電動旋耕機畢業(yè)論文（設(shè)計）工作進度已完成的主要內(nèi)容尚需解決的主要問題指導教師意見 指導教師簽名： 年 月 日檢查（考核）小組意見檢查小組組長簽名： 年 月 日學院生產(chǎn)實習成績考核表畢業(yè)學生姓名臧龍年級專業(yè)及班次2007級機械設(shè)計制造及其自動化(6)班起訖年月日自20 年 月 日至20 年 月 日實習地點實習內(nèi)容提要自我總結(jié)本人簽名： 20 年 月 日實習小組意見：組長簽名： 20 年 月 日實習單位意見：實習單位蓋章 20 年 月 日實習指導教師意見：指導教師簽名： 20 年 月 日系實習領(lǐng)導小組意見成績：評語：簽名： 20 年 月 日備注：成績分優(yōu)、良、中、及格、不及格五級記載。本表一式二份，實習結(jié)束后由系（部）匯總后交學院教務(wù)部：一份進入學生個人檔案，一份存學院檔案室。開題論證審批表學生姓名學號年級專業(yè)及班級指導教師及職稱開題時間年 月 日畢業(yè)論文（設(shè)計）題目電動旋耕機文獻綜述（選題研究意義、國內(nèi)外研究現(xiàn)狀、主要參考文獻等）選題研究意義：我國地形條件復雜，很多地方都是丘陵、山區(qū)，特別是南方地區(qū)其地形特點是地塊小、高差大、無機耕道、個人的小型花園難于耕作，所以現(xiàn)研究一種具有重量輕，體積小，結(jié)構(gòu)簡單等特點的小型微型旋耕機。又由于石化能源有限為不可再生資源而電能有水力發(fā)電風力發(fā)電為可再生能源，而且石油燃燒產(chǎn)生大量CO2等溫室氣體加劇全球溫室效應(yīng)。電動機噪聲小工作平穩(wěn)優(yōu)化了工作環(huán)境相比之下也減小了對其它部件的損耗；電動機無排放，少污染契合當前形勢有利于環(huán)境的保護。并且內(nèi)燃機燃燒的是柴油或汽油，排放的有毒氣體如CO SO2對人體和植物均有害，大棚內(nèi)通風狀況不良污染持續(xù)時間較長影響可能較大。為了進一步改善作業(yè)環(huán)境，本設(shè)計采用電動機為動力，以齒輪、皮帶輪、鏈輪作為傳動裝置，整機結(jié)構(gòu)穩(wěn)定、輕巧、體積小，而且整機價格不高能大范圍普及，適合于如南方農(nóng)民家庭小塊菜地果園以及小型個體戶大棚蔬菜花園的管理。國內(nèi)研究現(xiàn)狀：目前，旋耕機械在我國已被廣泛使用，正逐步發(fā)展成為農(nóng)業(yè)機械的一個重要門類。我國目前的驅(qū)動型耕作機械產(chǎn)品有旋耕機及復式作業(yè)機、驅(qū)動式圓盤犁、耕耙犁、水田驅(qū)動耙、立式轉(zhuǎn)齒耙等，但產(chǎn)量比較大的主要為旋耕機。目前，批量生產(chǎn)和推廣使用的2.2-74.6kw手扶拖拉機和乘坐式拖拉機配套旋耕機三大系列145種產(chǎn)品，系80年代末的更新?lián)Q代產(chǎn)品。90年代以來，國內(nèi)又研制了一批旋耕復式作業(yè)機具新產(chǎn)品，逐步投放市場。目前，國內(nèi)大中拖配套旋耕機保有量約15萬臺，手拖和小四輪配套旋耕機200萬臺。旋耕機在南方水稻生產(chǎn)機械化應(yīng)用中已占80%比例，北方的水稻生產(chǎn)、蔬菜種植和旱地滅茬整地也廣泛采用了旋耕機械。南稻北移，種值面積迅速增加，擴大了對旋耕機械的市場需求。水稻是高產(chǎn)作物，種植水稻有較高的經(jīng)濟效益。近年來，我國北方實施種植業(yè)結(jié)構(gòu)調(diào)整，大力推行旱改水，擴大水稻種植面積。由于農(nóng)作物的結(jié)構(gòu)調(diào)整，相應(yīng)的農(nóng)機裝備結(jié)構(gòu)正在發(fā)生變化，迫切需要從技術(shù)上、經(jīng)濟上合理配備適應(yīng)水旱田作業(yè)的拖拉機及配套農(nóng)機具。農(nóng)業(yè)產(chǎn)業(yè)化、集約化、規(guī)模經(jīng)營需要大型高效旋耕機械。隨著我國農(nóng)業(yè)產(chǎn)業(yè)化和適度規(guī)模經(jīng)營的發(fā)展，對大中型農(nóng)業(yè)機械的市場需求也日漸增大。不僅是農(nóng)墾系統(tǒng)國營農(nóng)場，而且鄉(xiāng)村農(nóng)機服務(wù)站以及個體的農(nóng)機專業(yè)戶，也需要更新和添置大中型農(nóng)業(yè)機械。對黑龍江墾區(qū)的調(diào)查表明，近年大量購置的水田耕整地機械已由中小功率拖拉機旋耕機組變化為鐵牛654和LF-904WD等大中功率輪式拖拉機及配套旋耕機。農(nóng)機專業(yè)戶使用這些大中型機械從事機耕服務(wù)，一般1-2年可回收本金，有誘人的經(jīng)濟效益?？傊S著中國經(jīng)濟的發(fā)展，需求的不斷提升，中國旋耕機市場從無到有，從小到大、從總量快速擴張到結(jié)構(gòu)明顯升級，逐步形成了有中國特色的多樣化、多層次的消費市場。旋耕機市場發(fā)展令世人矚目主要參考文獻與外文資料1 承繼成.精確農(nóng)業(yè)技術(shù)與應(yīng)用M.科學出版社，2004年2 蔣恩臣主編.農(nóng)業(yè)生產(chǎn)機械化M.中國農(nóng)業(yè)出版社，2003年3 何勇等主編.精確農(nóng)業(yè)M.浙江大學出版社，2003年4 高煥文主編.農(nóng)業(yè)機械化生產(chǎn)學M.中國農(nóng)業(yè)出版社，2002年5于海明,王紅飚,丁羽.微型旋耕機的設(shè)計J.農(nóng)機化研究，2003,1:86-87.6王遵義,蔬菜大棚用小型深旋耕機組的設(shè)計J.浙江萬里學院，1999,3:7-11.7李理,霍春明.我國旋耕機研究現(xiàn)狀及發(fā)展方向J.現(xiàn)代化農(nóng)業(yè)，2004,10:37-38.8李寶筏.農(nóng)業(yè)機械學M.北京：中國農(nóng)業(yè)出版社，2003:29-339濮良貴，紀明剛，陳國定等.機械設(shè)計，第八版M.北京：高等教育出版社，2001.10王昆,何小伯,汪信遠.機械設(shè)計及機械設(shè)計基礎(chǔ)課程設(shè)計M.北京：高等教育出版社，1995.11孫恒,陳作模,葛文杰,機械原理第七版M.北京：高等教育出版社，2006.12李濱,崔東.小型農(nóng)用旋耕機的設(shè)計J.林業(yè)機械與木工設(shè)備,2006,3:30-32.13丁海明,張雪,李連豪等.微型旋耕機的設(shè)計J.黑龍江八一農(nóng)耕學報，2007,4:33-35.注：此表如不夠填寫，可另加頁。研究方案（研究目的、內(nèi)容、方法、預期成果、條件保障等）研究目的：本設(shè)計為了適應(yīng)蔬菜大棚的大規(guī)模發(fā)展對農(nóng)機具的需求，并根據(jù)工作業(yè)環(huán)境和目前的經(jīng)濟技術(shù)條件的要求設(shè)計了微型電動旋耕機設(shè)計主要內(nèi)容：確定總體結(jié)構(gòu)方案，傳動方案，動力機選擇，傳動裝置的選擇主要零部件的設(shè)計與校核研究方法：收集資料-歸納分析，比較各種方案，確定總體方案-結(jié)構(gòu)系統(tǒng)的設(shè)計、傳動方案設(shè)計，齒輪鏈輪皮帶輪的比較與選取，受力分析軸承的選取預期成果：1萬字以上的設(shè)計計算說明書?？傃b圖、變速箱裝備圖、結(jié)構(gòu)示意圖、傳動原理示意圖、多張零部件圖。時間進程安排（各研究環(huán)節(jié)的時間安排、實施進度、完成程度等）2010.9.20 接受任務(wù)2010.09.212011.09.25 開題2010.10.12011.4.15 查資料設(shè)計2011.04.162011.05.1 總結(jié)書寫說明書；繪制設(shè)計圖樣；2011.05.12011.05.23 審查，修改，定稿。2011.05.242011.05.28 答辯，上交正稿開題論證小組意見 組長簽名： 年 月 日專業(yè)委員會意見專業(yè)教研室主任簽名： 年 月 日注：此表意見欄必須由相應(yīng)責任人親筆填寫。成績評定冊學生姓名學號年級專業(yè)及班級指導教師及職稱畢業(yè)論文（設(shè)計）題目SWDM-20旋挖鉆機液壓系統(tǒng)設(shè)計完成時間20 年 月 日答辯時間20 年 月 日摘要：關(guān)鍵詞：答辯資格審查意見：專業(yè)委員會主任簽名：20 年 月 日指導教師評語：指導教師建議成績： 指導教師簽名：年 月 日評閱教師評語：評閱教師建議成績： 評閱教師簽名：年 月 日答辯小組評語：答辯小組建議成績： 組長簽名：年 月 日成績評定綜合成績（百分制）：分折合五級記分制成績：答辯委員會審查意見：答辯委員會主任簽名：年 月 日成績評定說明：畢業(yè)論文（設(shè)計）的成績評定采用綜合加權(quán)評分的辦法，按指導教師評分占30%、論文評閱人評分占30%和答辯小組評分占40%計算出百分制的綜合成績，并根據(jù)綜合成績確定相應(yīng)五級記分制等級。系部答辯委員會對畢業(yè)論文（設(shè)計）的預評、評閱、答辯成績進行審查，對評定等級為優(yōu)秀或不及格以及答辯評分中有爭議的論文（設(shè)計）要進行重點審核，最終確定成績。指導教師、評閱教師、答辯小組應(yīng)分別嚴格按湖南農(nóng)業(yè)大學東方科技學院畢業(yè)論文（設(shè)計）評分標準中的相應(yīng)標準客觀、公正賦分。本表一式二份，一份進入學生個人檔案，一份存學院檔案室。指導教師指導檢查學生進行畢業(yè)論文（設(shè)計）工作情況登記表系（部）名稱：理工學部 指導教師姓名：李明時 間地 點指導、檢查的主要內(nèi)容學生簽名注：此表在每次指導、檢查工作時由學生帶來，指導教師填寫。內(nèi)容包括學生的學習、工作態(tài)度；畢業(yè)論文（設(shè)計）工作的進展情況；論文（設(shè)計）工作中尚需解決的問題等。設(shè)計 電動旋耕機設(shè)計DESIGN OF ELECTRIC ROTOTILLER學生姓名： 學 號： 年級專業(yè)及班級： 指導老師及職稱： 副教授湖南長沙提交日期：20 年 月誠信聲明本人鄭重聲明：所呈交的本科畢業(yè)設(shè)計是本人在指導老師的指導下，進行研究工作所取得的成果，成果不存在知識產(chǎn)權(quán)爭議。除文中已經(jīng)注明引用的內(nèi)容外，本論文不含任何其他個人或集體已經(jīng)發(fā)表或撰寫過的作品成果。對本文的研究做出重要貢獻的個人和集體在文中均作了明確的說明并表示了謝意。本人完全意識到本聲明的法律結(jié)果由本人承擔。 畢業(yè)設(shè)計作者簽名： 年 月 日目 錄摘 要 1關(guān)健詞11 前言21.1旋耕機研究現(xiàn)狀 21.2旋耕機發(fā)展趨勢 31.2.1多功能化 31.2.2小型化高度自動化31.2.2選用適應(yīng)性強的發(fā)動機31.2.3操作集成更加方便31.2.4更換工作部件快速化31.3旋耕機研究目的 32 總體設(shè)計42.1總體結(jié)構(gòu)方案確定42.2工作原理52.3傳動方案62.3.1旋耕機傳動類型的選擇 62.3.2傳動方案的確定 62.4主要參數(shù)的確定72.5動力和刀輥轉(zhuǎn)速的初步確定72.5.1動力的初步選擇 72.5.2刀軸轉(zhuǎn)速和前進速度初步確定 72.6發(fā)動機功率校核72.7旋耕刀的設(shè)計82.7.1旋耕刀的選擇 83主要零件的設(shè)計計數(shù) 93.1計算各軸的設(shè)計參數(shù)93.1.1傳動效率的選定 93.1.2各軸輸入功率 103.1.3各軸傳動比的分配 103.1.4各軸輸出轉(zhuǎn)矩 113.2齒輪的設(shè)計和校核 133.2.1圓柱齒輪副的設(shè)計和校核計算 143.2.2其他各直齒圓柱齒輪的幾何計算 153.3 鏈傳動的設(shè)計計算 163.3.1選擇鏈輪的齒數(shù) 163.3.2確定計算功率 163.3.3選擇鏈條型號和節(jié)距 163.3.4計算鏈節(jié)數(shù)和中心距 163.3.5計算鏈速確定潤滑方式 173.3.6計算壓軸力 173.3.7鏈輪的材料選擇 173.3.8鏈輪齒形的確定 173.4輸入軸的設(shè)計計算 183.4.1輸入軸的初步計算 183.4.2軸的結(jié)構(gòu)設(shè)計 193.4.3軸的強度校核 204 其它零部件的設(shè)計與選擇以及潤滑方法的選擇 224.1 聯(lián)軸器的選擇 224.2 限深裝置的設(shè)計224.3 潤滑方法225 結(jié)論 23參考文獻 23致 謝25電動旋耕機設(shè)計學 生：指導老師：摘 要：旋耕機是在我國廣大丘陵，山區(qū)，地塊小，高差大，無機耕道，果園、茶園、菜地、溫室大棚、丘陵坡地和小塊（水、旱田）作業(yè)的耕耘機械。本設(shè)計為了適應(yīng)蔬菜大棚的大規(guī)模發(fā)展對農(nóng)機具的需求，并根據(jù)工作業(yè)環(huán)境和目前的經(jīng)濟技術(shù)條件的要求設(shè)計了微型電動旋耕機。本次設(shè)計的旋耕機以電機為動力機。從旋耕機的總體方案，工作原理，旋耕刀的選擇以及傳動系統(tǒng)和控制系統(tǒng)做了比較全面的的設(shè)計分析，并對關(guān)鍵零部件進行了計算校核。本設(shè)計結(jié)構(gòu)簡單、輕巧、無廢氣排放,適于大棚的淺中耕作業(yè)。關(guān)鍵詞：旋耕機；刀輥；耕作刀具；減速箱。Design of electireic rototillerStudent:Tutor:Abstract: Rototiller is a kind of farming machinery which is particularly suited to the hills, mountainous areas, small plot of land, big altitude difference, no-tractor road, orchard, tea house, vegetable plots, greenhouse canopy, hill slopes and small pieces (water, dry farmland) . In order to adapt to the development of large-scale vegetables canopy, I conduct this design according to the demand of agricultural work environment and the present economic heritage requirements of technical conditions micro electric rototiller design. This rototiller is designed by making power generator based on motor. The comprehensive analysis of rototiller is conducted by analyzing overall scheme , working principle , the option of spin and plow knife transmission system and control system for a design, and the key components are calculated respectively. This rototiller has simple structure, light weight and zero emissions of waste gas ,and is used universally in rellis shallow intertillage of great pavilion.Key words:rototiller; knife; farming tool; reducer.1前言 旋耕機是以旋轉(zhuǎn)刀齒為工作部件的驅(qū)動型土壤耕作機械。又稱旋轉(zhuǎn)耕耘機。按其旋耕刀軸的配置方式分為橫軸式和立軸式兩類。以刀軸水平橫置的橫軸式旋耕機應(yīng)用較多。橫軸式旋耕機有較強的碎土能力，一次作業(yè)即能使土壤細碎，土肥摻和均勻，地面平整，達到旱地播種或水田栽插的要求，有利于爭取農(nóng)時，提高工效。但對殘茬、雜草的覆蓋能力較差，耕深較淺（旱耕1216厘米；水耕1418厘米），能量消耗較大泥，漏耕較嚴重。主要用于水稻田和蔬菜地，也用于果園中耕。重型橫軸式旋耕機的耕深可達2025厘米，多用于開墾灌木地、沼澤地和草荒地的耕作。切土刀片由前向后切削土層，并將土塊向后上方拋到罩殼和拖板上，使之進一步破碎。刀輥切土和拋土時，土壤對刀輥的反作用力有助于推動機組前進，因而臥式旋耕機作業(yè)時所需牽引力很小，有時甚至可以由刀輥推動機組前進。立軸式旋耕機工作部件為裝有23個螺線形切刀的旋耕器。作業(yè)時旋耕器繞立軸旋轉(zhuǎn)，切刀將土切碎。適用于稻田水耕，有較強的碎土、起漿作用，但覆蓋性能差。在日本使用較多。為增強旋耕機的耕作效果，在有些國家的旋耕機上加裝各種附加裝置。如在旋耕機后面掛接釘齒耙以增強碎土作用，加裝松土鏟以加深耕層等。小型旋耕機以小型內(nèi)燃機或電動機為動力，以整體式變速齒輪或皮帶鏈輪作為傳動，具有重量輕，體積小，結(jié)構(gòu)簡單，操作方便，易于維修，工作穩(wěn)定可靠，使用壽命長，油耗低，生產(chǎn)效率高等特點。旋耕機的機構(gòu)包括機架、可調(diào)高低扶手，機架上沒有的內(nèi)燃機或電動機、以及驅(qū)動輪和耕作刀具。旋耕機可以爬坡，越埂、階梯性強。廣泛適用于平原、山區(qū)、丘陵的旱地、水田、茶園、果園等。能淺旋耕、犁耕、開溝建壟。配上相應(yīng)機具可進行抽水、發(fā)點、噴藥、噴淋、收割、起壟、鋪膜、打孔、碎草等作業(yè)。旋耕機可以在田地、大朋、茶園等地方自由行使，便于用戶使用和存放，省去了大型農(nóng)用機械無法進入山區(qū)田地的煩惱，是廣大農(nóng)民消費者替代牛耕的最佳選擇，有大中型農(nóng)機無法媲美的優(yōu)勢，是進入農(nóng)民家庭最理想的小型農(nóng)機。 圖1 旋耕機Figure 1 Rototiller1.1旋耕機研究現(xiàn)狀目前，旋耕機械在我國已被廣泛使用，正逐步發(fā)展成為農(nóng)業(yè)機械的一個重要門類。 我國目前的驅(qū)動型耕作機械產(chǎn)品有旋耕機及復式作業(yè)機、驅(qū)動式圓盤犁、耕耙犁、水田驅(qū)動耙、立式轉(zhuǎn)齒耙等，但產(chǎn)量比較大的主要為旋耕機。目前，批量生產(chǎn)和推廣使用的2.2-74.6kw手扶拖拉機和乘坐式拖拉機配套旋耕機三大系列145種產(chǎn)品，系80年代末的更新?lián)Q代產(chǎn)品。90年代以來，國內(nèi)又研制了一批旋耕復式作業(yè)機具新產(chǎn)品，逐步投放市場。目前，國內(nèi)大中拖配套旋耕機保有量約15萬臺，手拖和小四輪配套旋耕機200萬臺。旋耕機在南方水稻生產(chǎn)機械化應(yīng)用中已占80%比例，北方的水稻生產(chǎn)、蔬菜種植和旱地滅茬整地也廣泛采用了旋耕機械。南稻北移，種值面積迅速增加，擴大了對旋耕機械的市場需求。水稻是高產(chǎn)作物，種植水稻有較高的經(jīng)濟效益。近年來，我國北方實施種植業(yè)結(jié)構(gòu)調(diào)整，大力推行旱改水，擴大水稻種植面積。由于農(nóng)作物的結(jié)構(gòu)調(diào)整，相應(yīng)的農(nóng)機裝備結(jié)構(gòu)正在發(fā)生變化，迫切需要從技術(shù)上、經(jīng)濟上合理配備適應(yīng)水旱田作業(yè)的拖拉機及配套農(nóng)機具。 農(nóng)業(yè)產(chǎn)業(yè)化、集約化、規(guī)模經(jīng)營需要大型高效旋耕機械。隨著我國農(nóng)業(yè)產(chǎn)業(yè)化和適度規(guī)模經(jīng)營的發(fā)展，對大中型農(nóng)業(yè)機械的市場需求也日漸增大。不僅是農(nóng)墾系統(tǒng)國營農(nóng)場，而且鄉(xiāng)村農(nóng)機服務(wù)站以及個體的農(nóng)機專業(yè)戶，也需要更新和添置大中型農(nóng)業(yè)機械。對黑龍江墾區(qū)的調(diào)查表明，近年大量購置的水田耕整地機械已由中小功率拖拉機旋耕機組變化為鐵牛654和LF-904WD等大中功率輪式拖拉機及配套旋耕機。農(nóng)機專業(yè)戶使用這些大中型機械從事機耕服務(wù)，一般1-2年可回收本金，有誘人的經(jīng)濟效益。 總之隨著中國經(jīng)濟的發(fā)展，需求的不斷提升，中國旋耕機市場從無到有，從小到大、從總量快速擴張到結(jié)構(gòu)明顯升級，逐步形成了有中國特色的多樣化、多層次的消費市場。旋耕機市場發(fā)展令世人矚目。1.2 旋耕機發(fā)展趨勢1.2.1 多功能化加裝掛接部件不斷配套新機具，增加新功能，在完善農(nóng)用功能的基礎(chǔ)上，逐步向城市園林、園藝領(lǐng)域擴展，如配套剪草、清雪、枝葉粉碎機具等。微耕機與配套機具的掛接采用快速掛接裝置，拆換農(nóng)具簡單、快速。1.2.2 小型化機具靈活性高便于運輸，能在小空間復雜地形工作1.2.3 選用適應(yīng)性強功耗少的發(fā)動機低噪聲、少污染、動力強勁和適應(yīng)性強的發(fā)動機將更多地被應(yīng)用。1.2.4 操作集成更加方便高度自動化操向手柄、前進和后退速度的調(diào)節(jié)更加方便1.3旋耕機研究目的和意義我國地形條件復雜，很多地方都是丘陵、山區(qū)，特別是南方地區(qū)其地形特點是地塊小、高差大、無機耕道、個人的小型花園難于耕作，所以現(xiàn)研究一種具有重量輕，體積小，結(jié)構(gòu)簡單等特點的小型微型旋耕機。又由于石化能源有限為不可再生資源而電能有水力發(fā)電風力發(fā)電為可再生能源，而且石油燃燒產(chǎn)生大量CO2等溫室氣體加劇全球溫室效應(yīng)，電動機噪聲小工作平穩(wěn)優(yōu)化了工作環(huán)境相比之下也減小了對其它部件的損耗；電動機無排放，少污染契合當前形勢有利于環(huán)境的保護。并且內(nèi)燃機燃燒的是柴油或汽油，排放的有毒氣體如CO SO2對人體和植物均有害。大棚內(nèi)通風狀況不良污染持續(xù)時間較長影響可能較大。為了進一步改善作業(yè)環(huán)境，本設(shè)計采用電動機為動力，以齒輪、皮帶輪、鏈輪作為傳動裝置，整機結(jié)構(gòu)穩(wěn)定、輕巧、體積小，而且整機價格不高能大范圍普及，適合于如南方農(nóng)民家庭小塊菜地果園以及小型個體戶大棚蔬菜花園的管理。2總體設(shè)計2.1總體結(jié)構(gòu)方案確定總體結(jié)構(gòu)設(shè)計包括傳送方案的確定，旋耕機耕幅的確定，旋耕機的傳動形式，前進的速度，刀軸的轉(zhuǎn)速的確定等內(nèi)容。結(jié)構(gòu)設(shè)計要體現(xiàn)設(shè)計原則和設(shè)計思想，實現(xiàn)旋耕機的結(jié)構(gòu)合理，達到可靠性，適用性，先進性，經(jīng)濟性及系統(tǒng)化的統(tǒng)一。期中參數(shù)的計算，型號的選擇是主要部分，在總體方案確定后才能進行具體的結(jié)構(gòu)和強度等方面的設(shè)計計算?？傮w結(jié)構(gòu)示意如圖2所示。圖2 總體結(jié)構(gòu)示意圖Figure 2 Overall structure schematic drawing2.2工作原理該機的變速箱設(shè)計“7”字形，中中間為圓柱齒輪副傳動所在的空間，突出部分為行走地輪的傳動分路所在空間，另外部分為旋耕刀傳動路線空間。因為傳動路線較長軸距相差較大，所以采用了兩個鏈輪傳動。該機具的工作原理是發(fā)動機的動力通過離合器和聯(lián)軸器將動力輸出軸的動力傳遞給皮帶輪軸，再經(jīng)鏈輪傳動到變速箱的輸入軸經(jīng)行走傳動線路三級減速后傳到行走輸出軸帶動行走地輪轉(zhuǎn)動，實現(xiàn)機械的行走。另外一邊輸入軸運動經(jīng)三級減速傳遞到旋耕軸，實現(xiàn)機械的旋耕作業(yè)。離合器安裝在發(fā)動機前端，其功用是：在停車時切斷發(fā)動機與傳動裝置之間的動力；旋耕機起步時能平穩(wěn)結(jié)合發(fā)動機與傳送裝置間的動力；旋耕機遇到過大的阻力時，離合器便打滑，以免損壞傳動系統(tǒng)零件，起到保駕護航的作用。耕深主要是通過支架上升降控制部分不同位置進行調(diào)節(jié)，同時還可以通過人對操作手柄的壓力的改變以增減力矩，調(diào)節(jié)機器的前進速度，借以達到改變耕深的目的。另外旋耕作業(yè)的碎土性能與土壤含水量，土壤堅實度和機器的作業(yè)速度有關(guān)，本文只針對一種速度進行設(shè)計。2.3傳動方案 2.3.1 旋耕機傳動類型的選擇旋耕的類型按刀軸傳動方式分，可分為中間傳動式旋耕機和側(cè)邊傳動式旋耕機。本設(shè)計采用側(cè)邊傳動式旋耕機。側(cè)邊傳動多用于耕幅較小的偏置式旋耕機。中央傳動用于耕幅較大的旋耕機，機器的對稱性好，整機受力均勻；但傳動箱下面的一條地帶由于切土刀片達不到而形成漏耕，需另設(shè)消除漏耕的裝置。2.3.2 傳動方案的確定帶傳動具有結(jié)構(gòu)簡單，傳動平穩(wěn)，價格低廉和緩沖吸振的特點。齒輪傳動具有傳動效率高，本身配合結(jié)構(gòu)緊湊，體積較小的特點。鏈傳動特點介于前兩者之間適于兩軸相距較遠的場合而且與齒輪相比較輕和價格低所以本設(shè)計變速箱選擇采用齒輪傳動和鏈傳動的混合的方式來實現(xiàn)動力旋耕機刀軸的運動傳遞。外部傳動則以皮帶輪與鏈輪的混合方式來傳遞動運動。工作可靠簡單成本較低。傳動方案如圖3所示。圖3 傳動方案示意圖 Figure 3 Transmission scheme 2.4主要參數(shù)的確定根據(jù)設(shè)計任務(wù)書的要求，此旋耕機是用于大棚旋耕松土作業(yè)的微型旋耕機，所涉及的旋耕機能完成大棚除草、松土和起壟等作業(yè)。要求動力為0.75kw；深耕為1216cm；淺耕36cm；耕幅為3080cm；工作效率為3畝4畝/8小時；整機質(zhì)量100kg。2.5動力和刀輥轉(zhuǎn)速的初步確定2.5.1電動機的初步選擇初步選擇電動機：合力ZLCF 直流有刷電機，額定功率：3.6kw；額定轉(zhuǎn)速：3000r/min；凈重15kg。2.5.2刀軸轉(zhuǎn)速和前進速度初步確定耕深為12cm，耕幅為40cm，工作效率為4畝/h。可以得出機組前進速度Vm=0.8m/s。2.6 發(fā)動機功率校核旋耕機工作時所需功率的計算，在旋耕作業(yè)過程中，旋耕機工作所需的功率與多種因素有關(guān)，如耕地的地形，耕深，耕幅，耕速和土壤的性質(zhì)等功率的消耗主要包括旋耕刀切削土壤消耗的功率，拋土塊所消耗的功率推動前所消耗的功率，傳動部分所消耗的功率及土壤沿水平方向作用與刀輥上的反作用力所消耗的功率。設(shè)計時，先假定機組在比較平坦的田地里進行勻速直線作業(yè)，旋耕機工作時所需的功率可以按下列經(jīng)驗公式進行估算： 式中 耕深（cm）； 機組前進速度（m/s）； 耕幅（m）； 旋耕比組（）；其中由于切土節(jié)距，所以依據(jù)農(nóng)業(yè)機械設(shè)計手冊（上冊）238頁表4-3-4查得，。則：=那么：因此，發(fā)動機功率滿足設(shè)計要求。2.7旋耕刀的設(shè)計2.7.1 旋耕刀的選擇旋耕刀是旋耕機的主要工作部件，刀片的形狀和參數(shù)直接影響旋耕的工作質(zhì)量，目前國內(nèi)外對旋耕刀刃口曲線形狀和結(jié)構(gòu)參數(shù)作了大量研究，就橫軸旋機上的刀齒而言主要有剛性和彈性兩大類，剛性刀按其外形分又可分為鑿形刀、彎刀、直角刀和弧形刀。鑿形刀前端較窄，有較好的入土能力，能量消耗小，但易纏草，多用于雜草少的菜園和庭院。彎刀的彎曲刃口有滑切作用，易切斷草根而不纏草，適于水稻田耕作。直角刀具有垂直和水平切刃，刀身較寬，剛性好，容易制造，但入土性能較差?；⌒蔚兜膹姸却?，剛性好，滑切作用好，通常用于重型旋耕機上。根據(jù)GB/T5669-1995，旋耕刀分為型刀，型刀和刀型。型刀主要用于水旱田耕作。刀輥回轉(zhuǎn)半徑R有225、245、260mm三種；型刀主要用于水田綠肥，稻茬，麥茬較多的田地作業(yè)。刀輥回轉(zhuǎn)半徑有195、210、225、245、260mm五種；刀型主要用于淺耕滅茬作業(yè)，刀輥回轉(zhuǎn)半徑R有150、175mm兩種。根據(jù)設(shè)計要求，選用S150型淺耕滅茬旋耕刀，采用65Mn鋼。刀片結(jié)構(gòu)如圖2所示。圖4 旋耕刀結(jié)構(gòu)圖Figure 4 Spin plow knife structure 查得：， 由于彎刀在切土時刀端撕裂附近土壤，因此刀座間距應(yīng)大于彎刀工作寬幅約為20mm，由于彎刀的工作寬幅為40mm，耕幅為400mm，通過計算知刀軸上能排列6個刀座。 在排列刀片的過程中，為了解決旋耕機工作時向測邊輸土的問題，可以使左右刀片的兩條螺旋線不連續(xù)，而且旋向不一樣，并且相鄰區(qū)段螺旋線的旋向相反；在焊接左右的時候，同一回轉(zhuǎn)平面的左右彎刀的間隔夾角應(yīng)該在90和180之間，因此確定一個刀座上同一回轉(zhuǎn)平面的兩把刀的間隔夾角為180。彎刀排列展開圖如圖3所示圖5 刀片螺旋線對稱排列Figure 5 Selical symmetrical arrangement blades3 主要零件的設(shè)計計數(shù)3.1 計算各軸的設(shè)計參數(shù)3.1.1 傳動效率的選定由傳動方案圖4可以看出，從發(fā)動機到旋耕機刀軸，效率傳遞都包括離合器、聯(lián)軸器、滾動軸承、圓柱齒輪、皮帶輪、鏈輪等的傳遞。其中取傳動效率值分別為：離合器，聯(lián)軸器，軸承，皮帶輪圓柱齒輪，鏈輪。3.1.2 各軸輸入功率各軸輸入功率分別為：；。3.1.3 各軸傳動比的分配總傳動比計算如圖4所示，由于發(fā)動機轉(zhuǎn)速為3000r/min，刀軸轉(zhuǎn)速為100r/min。則總傳動比。各軸傳動比分別為，變速箱總傳動比旋耕線路，行走線路。則各軸的轉(zhuǎn)速分別為：;或。3.1.4 各軸輸出轉(zhuǎn)矩；。3.2 齒輪的設(shè)計和校核3.2.1 第一級圓柱齒輪副的設(shè)計和校核計算根據(jù)傳動方案選用直齒圓柱齒輪傳動。根據(jù)GB/T10095.1農(nóng)業(yè)機械中重要齒輪選用8級精度。選擇小齒輪的材料為40Cr，調(diào)質(zhì)后表面淬火，硬度280HBS，大齒輪材料為45鋼，調(diào)質(zhì)后表面淬火硬度為240HBS。壓力角，齒數(shù)的選擇，選擇小齒輪齒數(shù)為，則大齒輪的齒數(shù)。按齒面接觸強度設(shè)計確定公式內(nèi)各計算數(shù)值：試選載荷系數(shù)；計算小齒輪傳遞的轉(zhuǎn)矩。小齒輪轉(zhuǎn)速小齒輪傳遞的轉(zhuǎn)矩為由機械設(shè)計表10-7，該圓柱齒輪兩支撐相對于小齒輪做不對稱布置，選取齒寬系數(shù)；由機械設(shè)計表10-6，查得材料的彈性影響系數(shù)；由機械設(shè)計圖10-21，按齒面硬度查得小齒輪的接觸疲勞強度極限，大齒輪的接觸疲勞強度極限。計算應(yīng)力循環(huán)次數(shù)根據(jù)應(yīng)力循環(huán)次數(shù)，由機械設(shè)計圖10-19，取接觸疲勞壽命系數(shù)，。計算接觸疲勞許用應(yīng)力。取失效概率為1%，安全系數(shù)S=1，得：試計算小齒輪分度圓直徑，帶入中取小的值。計算圓周速度。計算齒寬。齒寬與齒高之比模數(shù) 齒高 根據(jù)v=3.02m/s，8級精度，由機械設(shè)計圖10-8，查得動載系數(shù)，直齒輪；由機械設(shè)計表10-2，查得；由機械設(shè)計表10-4，查得；根據(jù)，由機械設(shè)計圖10-13查得。故載荷系數(shù)：按實際的載荷系數(shù)校正所得的分度圓直徑得：計算模數(shù)m：按齒根彎曲強度設(shè)計彎曲強度計算公式為確定公式內(nèi)的各計算數(shù)值由機械設(shè)計圖10-20c，查得小齒輪的彎曲疲勞強度極限，大齒輪的彎曲強度極限；由機械設(shè)計圖10-18取彎曲疲勞壽命系數(shù)，；取彎曲疲勞安全系數(shù)S=1.4,得：計算載荷系數(shù)：查取齒形系數(shù)。由機械設(shè)計表10-5，得齒形系數(shù)，；查取應(yīng)力校正系數(shù)。由機械設(shè)計表10-5，得應(yīng)力校正系數(shù)，；計算大、小齒輪并加以比較比較可得大齒輪的數(shù)值大。設(shè)計計算由于齒輪模數(shù)m的大小組要取決于彎曲強度所決定的承載力，而齒面接觸疲勞強度所決定的承載力，僅與齒輪直徑（即模數(shù)與齒數(shù)的乘積）有關(guān)，可取由彎曲疲勞強度算的的模數(shù)1.536并就近圓整為標準值m=2mm。幾何計算計算分度圓直徑計算中心距 計算齒輪寬度取，計算公法線 齒輪結(jié)構(gòu)設(shè)計齒頂高齒根高齒全高齒頂高直徑齒根圓直徑基圓直徑齒厚3.2.2 其他各直齒圓柱齒輪的幾何計算減速器另一對配合齒輪幾何尺寸：選擇齒數(shù)，計算分度圓直徑計算中心距計算齒輪寬度取，計算公法線 齒全高齒頂高直徑基圓直徑齒厚3.3 鏈傳動的設(shè)計計算3.3.1 選擇鏈輪的齒數(shù)取小鏈輪齒數(shù)，大鏈輪齒數(shù)為3.3.2 確定計算功率由機械設(shè)計表9-6查得，由機械設(shè)計圖9-13查得，單排鏈，則計算功率為：3.3.3 選擇鏈條型號和節(jié)距根據(jù)及查機械設(shè)計圖9-11，可選08A。查機械設(shè)計表9-1，鏈條節(jié)距，滾子直徑，內(nèi)鏈節(jié)內(nèi)寬。3.3.4 計算鏈節(jié)數(shù)和中心距初選中心距。?。骸Ｏ鄳?yīng)的鏈長節(jié)數(shù)為： 取鏈長節(jié)數(shù)節(jié)。查機械設(shè)計表9-8得：中心距計算系數(shù)，則鏈傳動最大 。3.3.5 計算鏈速，確定潤滑方式由和鏈號08A，查機械設(shè)計圖9-14可知應(yīng)采用滴油潤滑。3.3.6 計算壓軸力有效圓周力為鏈輪垂直布置時的壓力系數(shù)，則壓軸力為：3.3.7 鏈輪的材料選擇小輪用20鋼，經(jīng)淬火，回火處理，硬度60HRC；大輪用35鋼，經(jīng)正火處理，硬度200HBS。3.3.8 鏈輪齒形的確定齒側(cè)圓弧半徑滾子定位圓弧半徑分度圓直徑齒頂圓直徑齒寬齒側(cè)倒角齒側(cè)半徑3.4 輸入軸的設(shè)計計算3.4.1 輸入軸的初步計算 （1）選擇軸的材料和熱處理方式：選擇軸的材料為45鋼，調(diào)制處理，由機械設(shè)計表15-1查得，抗拉強度極限，屈服強度極限，彎曲疲勞極限，剪切疲勞強度極限，許用彎曲應(yīng)力。 （2）初步確定軸的最小直徑 由機械設(shè)計表15-3，取，于是得由于軸的最小直徑過小，取軸直徑為15mm。（3）初選軸承應(yīng)軸同時受有徑向力和軸向力作用，故選用深溝球軸承。根據(jù)工作要求及輸入端直徑，選用型號為6004的軸承（GB/T276-1994）。3.4.2 軸的結(jié)構(gòu)設(shè)計輸入軸的各段直徑和長度設(shè)計如圖5所示。圖6 輸入軸的結(jié)構(gòu)Figure 6 input shaft structure3.4.3 軸的強度校核（1）求作用在齒輪上的力應(yīng)為該齒輪為標準齒輪，則，那么圓周力徑向力圓周力，徑向力的方向如圖6所示。圖7 軸的載荷分布圖Figure 7 axis of load distribution（2）求軸上的載荷首先根據(jù)軸的結(jié)構(gòu)圖做出軸的計算簡圖。對于6004型深溝球軸承，由機械設(shè)計、機械設(shè)計基礎(chǔ)課程設(shè)計中查得B=12mm。因此作為簡支梁的軸的支撐跨距。根據(jù)軸的計算簡圖做出軸的彎矩圖和扭矩圖（如圖6）。軸上的作用力支反力總彎矩扭矩（3）按彎矩合成應(yīng)力校核軸的強度進行校核時，通常只校核軸上承受最大彎矩和扭矩的界面強度。根據(jù)機械設(shè)計公式15-5及表2中的數(shù)據(jù)，以及軸單向旋轉(zhuǎn)，扭切應(yīng)力為脈動循環(huán)應(yīng)力，取，軸的計算應(yīng)力故安全。4 其它零部件的設(shè)計與選擇以及潤滑方法的選擇4.1 聯(lián)軸器的選擇取載荷系數(shù)，則聯(lián)軸器的計算轉(zhuǎn)矩為根據(jù)計算轉(zhuǎn)矩、最小軸徑、軸的轉(zhuǎn)速，GB/T5843-2003，選用GY型凸緣聯(lián)軸器。4.2 調(diào)節(jié)耕深裝置的設(shè)計旋耕機是一種作業(yè)范圍較廣的農(nóng)用機械，在根據(jù)不同的土壤條件和工作要求，需要不同的旋耕深度。對于由電動機帶動的微型旋耕機，其深度可以用手動調(diào)節(jié)，即用升降控制桿上的螺栓來調(diào)節(jié)旋耕深度。能實現(xiàn)深耕：12-20cm；淺耕：3-10cm。此設(shè)計簡單實用，通過調(diào)節(jié)螺栓決定旋耕刀的高度符合旋耕機質(zhì)量輕、價格低、容易維修的特點。4.3 潤滑方法滾動軸承是一種重要的機械元件，一臺機械設(shè)備的性能能否充分發(fā)揮出來取決于軸承的潤滑是否適當。可以說，潤滑是保證軸承正常運轉(zhuǎn)的必要條件，它對于提高軸承的承載能力和使用壽命起著重要作用，滾動軸承潤滑一般可以根據(jù)使用的潤滑劑種類分為油潤滑、脂潤滑和固體潤滑三大類。不論采用何種潤滑形式，潤滑在滾動軸承中都能起到減小摩擦損失、提高傳動效率、防止銹蝕和降低噪音的作用。本機減速箱的軸承潤滑選擇齒輪油飛濺潤滑，后腔和刀軸上的軸承采用脂潤滑。因為在減速箱前腔的轉(zhuǎn)速比較高，所以比較適合采用油潤滑，而在后腔和刀軸上的轉(zhuǎn)速比較低，所以可以采用脂潤滑。再者，本機重量輕、結(jié)構(gòu)簡單、便于拆卸，而且一次性工作時間不長，所以可以在每次使用前先拆卸下來補充潤滑脂，以保證每次工作時的潤滑性。5 總結(jié)經(jīng)過2個月的努力，終于完成了電動旋耕機的設(shè)計。內(nèi)容主要有整體方案的確定傳動線路的設(shè)計，行走部分和旋耕部分的結(jié)構(gòu)設(shè)計題目的綜合訓練比較強，涉及知識面廣，重點在于培養(yǎng)工程思想及意識，理論聯(lián)系實際，提高初步設(shè)計能力。在設(shè)計過程中，我綜合運用了四年來所學到的專業(yè)知識，感覺到自己專業(yè)知識中一些欠缺，通過再次的復習，明顯感覺到了知識的增長，我從中學到了很多的知識，也體會到了畢業(yè)設(shè)計的綜合性，結(jié)合輔導老師的指導與自己的專業(yè)知識和生產(chǎn)實踐，才能較為完整地完成此次設(shè)計任務(wù)。看過不少資料，也讓我對于農(nóng)業(yè)機械有了更多的了解。整個設(shè)計一直秉承著簡單、方便、實用的原則。以方便能夠使用上它的人。參考文獻1 承繼成.精確農(nóng)業(yè)技術(shù)與應(yīng)用M.科學出版社，2004年2 蔣恩臣主編.農(nóng)業(yè)生產(chǎn)機械化M.中國農(nóng)業(yè)出版社，2003年3 何勇等主編.精確農(nóng)業(yè)M.浙江大學出版社，2003年4 高煥文主編.農(nóng)業(yè)機械化生產(chǎn)學M.中國農(nóng)業(yè)出版社，2002年5于海明,王紅飚,丁羽.微型旋耕機的設(shè)計J.農(nóng)機化研究，2003,1:86-87.6王遵義,蔬菜大棚用小型深旋耕機組的設(shè)計J.浙江萬里學院，1999,3:7-11.7李理,霍春明.我國旋耕機研究現(xiàn)狀及發(fā)展方向J.現(xiàn)代化農(nóng)業(yè)，2004,10:37-38.8李寶筏.農(nóng)業(yè)機械學M.北京：中國農(nóng)業(yè)出版社，2003:29-339濮良貴，紀明剛，陳國定等.機械設(shè)計，第八版M.北京：高等教育出版社，2001.10王昆,何小伯,汪信遠.機械設(shè)計及機械設(shè)計基礎(chǔ)課程設(shè)計M.北京：高等教育出版社，1995.11孫恒,陳作模,葛文杰,機械原理第七版M.北京：高等教育出版社，2006.12李濱,崔東.小型農(nóng)用旋耕機的設(shè)計J.林業(yè)機械與木工設(shè)備,2006,3:30-32.13丁海明,張雪,李連豪等.微型旋耕機的設(shè)計J.黑龍江八一農(nóng)耕學報，2007,4:33-35.14 孫恒,陳作模主編.機械原理M. 北京:高等教育出版社,2000：263-27315 朱孝錄主編.中國機械設(shè)計大典M.江西科學技術(shù)出版社，2002:166-21516 張淑娟,全臘珍主編.畫法幾何與機械制圖M.中國農(nóng)業(yè)出版社,2007:2-306致 謝在李明副教授的指導下，順利完成了本次畢業(yè)設(shè)計。在本設(shè)計的開題論證、課題研究、論文撰寫和論文審校整個過程中，得到了李明老師的親切關(guān)懷和精心指導，使得本設(shè)計得以順利完成，其中飽含了李明老師的汗水和心血。老師敏銳的學術(shù)思想、嚴謹踏實的治學態(tài)度、淵博的學識、精益求精的工作作風、誨人不倦的育人精神，將永遠銘記在學生心中，將使學生終生受益。在此我向李明老師表示衷心的感謝。同時也感謝工學院各位老師在這四年來對我的熱心的教導! 同時還要感謝同學對我的幫助。謝謝大家！- 25 -選題審批表專業(yè)：機械設(shè)計制造及其自動化畢業(yè)論文（設(shè)計）題目電動旋耕機設(shè)計選題來源（）結(jié)合科研課題課題名稱：4YJ05（ ）生產(chǎn)實際或社會實際（ ）其他選題性質(zhì)（）基礎(chǔ)研究（）應(yīng)用研究（）其他選題完成形式（）畢業(yè)論文（）畢業(yè)設(shè)計（）提交作品，并撰寫論文指導教師姓名李明職稱副教授是否主持或參與過科研課題（）是（）否選題依據(jù)（科學性、可行性論證）和內(nèi)容簡要農(nóng)業(yè)機械化是農(nóng)業(yè)現(xiàn)代化的物質(zhì)基礎(chǔ)，中央從2004年開始，連續(xù)7年1號文件強調(diào)加強農(nóng)業(yè)機械化發(fā)展；2002年中央2號文件明確指出將農(nóng)業(yè)機械化作為國家的發(fā)展戰(zhàn)略目標，因此，農(nóng)業(yè)機械的研究具有重要的社會和實際意義。本設(shè)計為了適應(yīng)蔬菜大棚的大規(guī)模發(fā)展對農(nóng)機具的需求，并根據(jù)工作業(yè)環(huán)境和目前的經(jīng)濟技術(shù)條件的要求設(shè)計了微型電動旋耕機。專業(yè)委員會意見專業(yè)委員會主任簽名：2010 年月日注：1.請在選項前的“（ ）”內(nèi)打“”；意見欄必須由相應(yīng)責任人親筆填寫，不夠填寫時可另加頁。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).