山楂去核機設(shè)計【說明書+CAD+UG】

山楂去核機設(shè)計【說明書+CAD+UG】,說明書+CAD+UG,山楂去核機設(shè)計【說明書+CAD+UG】,山楂,山查,去核機,設(shè)計,說明書,仿單,cad,ug 山楂去核機設(shè)計方案首先整個設(shè)計思路是這樣的：一 轉(zhuǎn)盤部分： 1 電機選低速電機選：90TDY060-3A2.轉(zhuǎn)盤上放12個山楂固定位，轉(zhuǎn)動過程中實現(xiàn)3秒轉(zhuǎn)動一個固定位，也就是說山楂固定轉(zhuǎn)盤轉(zhuǎn)速為3秒轉(zhuǎn)動12其中2秒多為停頓時間，方便手工放入山楂。3.減速方案:我們選用的電機轉(zhuǎn)速為每秒一轉(zhuǎn)，而間歇機構(gòu)要實現(xiàn)3秒一轉(zhuǎn)，才行能大轉(zhuǎn)盤3秒轉(zhuǎn)動12，所以這里我們只需把電機輸出速度降低到三分之一就能實現(xiàn)轉(zhuǎn)盤的轉(zhuǎn)速需求，這里參考到別的山楂機的多個案例決定采用皮帶減速機構(gòu)實現(xiàn)，二 去核部分1.去核部分運動采用曲柄連桿機構(gòu)來實現(xiàn)。2.首先電機選擇考慮到轉(zhuǎn)盤需要3秒轉(zhuǎn)動一個工位，所以對應(yīng)刀具也要3秒一個行程，如上圖所示原理，即曲柄轉(zhuǎn)動一周為一個行程為3秒 所以我們采用相同電機，所以也需降速三分之一，這里我們用齒輪減速，一個用模數(shù)1.5齒數(shù)12主動齒輪帶動模數(shù)1.5齒數(shù)36的從動輪。3刀內(nèi)殘渣 為了去除刀具中的殘渣，我們在刀具中安裝了一個小彈簧，擠壓時彈簧壓縮，當不受外力時彈簧能把殘渣彈出去。編號(學(xué)號)：*畢 業(yè) 設(shè) 計 ( *屆本科) 題 目： 山楂山楂機主要部件設(shè)計 學(xué) 院： * * * * 專 業(yè)： * 姓 名： * 指導(dǎo)教師： * 完成日期： * 年 * 月 * 日目錄摘要1Abstract21 前言31.1本論文研究的目的和意義31.2國內(nèi)外果核類山楂機械的發(fā)展情況31.3山楂的特性和山楂山楂機的應(yīng)用前景52 山楂山楂機的設(shè)計52.1 馬達的選擇62.1.1 選擇馬達系列62.1.2 選擇馬達功率72.2 傳動裝置的選擇72.2.1 傳動的選擇72.2.2 V帶傳動的設(shè)計83 山楂山楂機關(guān)鍵部件設(shè)計103.1 去核的刀具103.1.1 去核的刀具材料及尺寸103.2 山楂定位盤103.2.1 山楂定位盤材料103.2.2 山楂定位盤尺寸103.3 山楂機定位盤主軸113.3.1 軸的材料選擇113.3.2 初步估算軸徑113.3.3 軸的結(jié)構(gòu)設(shè)計113.3.4 軸的強度驗算123.4 山楂機主軸間歇輪133.5 山楂機傳動圓盤133.6 山楂機傳動軸143.6.1 軸的材料選擇143.6.2 初步估算軸徑143.6.3 軸的結(jié)構(gòu)設(shè)計143.6.4 軸的強度驗算143.7 軸承的選擇153.7.1 載荷條件163.7.2 軸承轉(zhuǎn)速163.7.3 調(diào)心性能163.7.4 軸承剛度163.7.5 安裝及拆卸要求163.7.6 經(jīng)濟性163.7.7 軸承壽命163.8 連桿設(shè)計183.9 山楂去核機裝配圖184 總結(jié)20參考文獻21致謝23*摘要我國目前的山楂山楂機械的發(fā)展情況比較落后，由于缺少良好的設(shè)備，加工手段落后，生產(chǎn)效率低，致使一些地區(qū)出現(xiàn)水果積壓腐爛現(xiàn)象，給果農(nóng)造成很大的經(jīng)濟損失。山楂去核手工作業(yè)現(xiàn)在在中國仍然是主要的加工手段，不僅占用大量的勞動力、勞動強度大、生產(chǎn)率低，而且衛(wèi)生安全也得不到有效保障。去核作業(yè)是山楂加工工序中十分重要的前處理工序。以往的手工操作遠不能滿足現(xiàn)代山楂加工的需求，不僅占用大量的勞力，勞動強度大，生產(chǎn)效率低，且產(chǎn)品質(zhì)量難以控制。本設(shè)計主要是為了解決山楂去核作業(yè)的勞動強度大，安全衛(wèi)生，提高生產(chǎn)效率，降低山楂果實破損率，保證山楂產(chǎn)品的質(zhì)量。因此，小型山楂山楂機有非常好的應(yīng)用前景。關(guān)鍵詞：山楂；山楂機；設(shè)計Abstract Development situation of Chinas current Hawthorn nuclear machinery is relatively backward, due to the lack of good equipment, processing methods are backward, low production efficiency, resulting in some areas appear fruit backlog rotten phenomenon, caused great economic losses to farmers. Hawthorn nuclear manual operation now in China is still the main means of processing, not only takes up a lot of labor, high labor intensity, low productivity, and health and safety are not effectively guarantee. Pitted pretreatment procedure is very important in the process of hawthorn processing. The old manual operation cannot meet the modern Hawthorn processing requirements, not only takes up a lot of labor, labor intensity is high, the production efficiency is low, and the product quality is difficult to control. This design is mainly to solve the Hawthorn nuclear operation labor intensity, safety and health, improve production efficiency, reduce the damage rate of hawthorn hawthorn fruit, guarantee the quality of the products. Therefore, application prospect of small Hawthorn nuclear machine has a very good.Keywords: haw；stoner；design1 前言1.1本論文研究的目的和意義我國的地域遼闊、資源豐富。具有得天獨厚的發(fā)展水果加工業(yè)的良好條件。水果深加工已成了農(nóng)民致富的一條主要途徑，不論社會效益還是經(jīng)濟效益都是十分可觀的。果核類水果主要是指桃、杏、李、山楂、紅棗及橄欖等。它們在水果總產(chǎn)量中占有較大比例，以它們?yōu)樵?，加工成飲料、罐頭、果脯及果干制品時，去核作業(yè)是水果加工業(yè)中十分重要的前處理工序。以前的手工操作遠不能滿足現(xiàn)代水果加工的需求，不僅占用大量的勞力，勞動強度大，生產(chǎn)效率低，且產(chǎn)品質(zhì)量難以控制。但是我們也看到，在果樹種植業(yè)蓬勃發(fā)展的今天，由于缺少性能良好的設(shè)備，加工的手段落后，生產(chǎn)效率低，有些地區(qū)還出現(xiàn)鮮果品積壓腐爛現(xiàn)象，給果農(nóng)造成不應(yīng)有的經(jīng)濟損失。許多地區(qū)的果品加工廠，其前處理生產(chǎn)環(huán)節(jié)，如去核、去皮、清洗等，至今基本上仍靠手工或十分簡陋的工具完成。因此，在我國發(fā)展山楂機械等前處理設(shè)備，取代手工作業(yè)是必然趨勢。針對中國水果資源豐富、分布廣泛的特點，特別要加大對中小型山楂去核機具的研制，以適應(yīng)廣大果農(nóng)及小型果品加工廠的需求。只有這樣，才會有豐富多樣的食品來滿足人們的需求，才能保護果農(nóng)種植的積極性。1.2 國內(nèi)外果核類山楂機械的發(fā)展情況國外20世紀60年代著手研制水果山楂機，至20世紀80年代初美國、意大利、荷蘭等國已相繼推出了粘核桃山楂機、橄欖山楂機等。去核工序基本上實現(xiàn)了自動化。數(shù)十年的發(fā)展，已日趨完善、成熟。目前，正向著節(jié)能型和機電一體化方向發(fā)展，以電腦自控作業(yè)為主。但中國的水果山楂機具發(fā)展緩慢，遠遠落后于種植業(yè)的發(fā)展。日本生產(chǎn)的一種刮板式山楂機，去核后的果肉可達5毫米左右，由篩孔排出，桃核從尾端排出，該機適用于粘核型桃的去核加工，它具有成本較低，生產(chǎn)率高，去核效果好等特點。國外也研制出了橄欖山楂機，它可以依靠果模組裝在鏈條或滾筒上，形成輸送和定位，并采用一排刀具（包括上刀和下刀），對橄欖進行多刀去核作業(yè)，其生產(chǎn)效率比使用單刀的設(shè)備高得多。美國FMC公司80年代初向市場推出一種自動轉(zhuǎn)矩式粘核桃山楂機。每分鐘可加工80個桃子，其生產(chǎn)率約800 kg/h左右。該機采用14個小杯對桃子進行定位和輸送。每個杯子底部有一帶凸起的小轉(zhuǎn)軸（見圖1）。小軸在鏈條帶動下始終旋轉(zhuǎn)著，只要杯內(nèi)桃子的凹部不在小凸起的上方，桃子外圈就會與凸起接觸并被其帶動旋轉(zhuǎn)著，直到圖示正確位置為止。這時，桃子保持直立狀態(tài)，劈刀將果內(nèi)劈成兩半后，夾持挑子的兩個橡膠夾板相向轉(zhuǎn)動150使果肉與桃核分離。該機可以整個加工季節(jié)連續(xù)工作而不必停機潤滑，調(diào)節(jié)與清洗也十分方便。由于它保持了去核后果肉的完整性，因此比較適合于罐頭、果脯和果干加工廠使用。由于該機結(jié)構(gòu)較復(fù)雜，成本較高，而國內(nèi)罐頭、果脯等食品均屬微利產(chǎn)品，因此，在我國推廣起來存在一些難度。圖1 桃子自動定位示意圖1轉(zhuǎn)軸2果杯3夾板意大利BERTUZZI公司推出了一種滾子山楂機，其原理如圖2所示。它適合于離核型桃、杏、李等核果的果肉與果核分離。圖中滾子2心部材料為碳鋼，外面覆蓋一層彈性適中的橡膠層，輥子3由數(shù)個齒狀圓盤組成，各盤間有一定間隔，在兩輥子上方有一推壓裝置，當它將物料推入兩輥子之間時，物料1在兩輥子的擠壓下，果肉被擠入齒輥中的齒間間隔（圖中5），而果核則使?jié)L子2的橡膠層變形而凹入橡膠層中（圖中4）。當轉(zhuǎn)過一定角度后，橡膠的彈性作用使果核脫離滾子2而進入果核收集斗。在輥子下方有一可調(diào)的分離裝置使肉核有效分離，在齒輥下方還有一個類似梳子的裝置將嵌在滾子3齒盤間的果肉梳出，落入果肉收集斗。從而達到核肉分離的目的。它適用于帶肉果汁飲料、果漿、果醬、果汁飲料等品種的去核工序，具有生產(chǎn)效率高等特點，有較高的推廣價值。圖2 滾子山楂機去核原理圖中國研制出的核果水果山楂機具，按其結(jié)構(gòu)特點和工作部件的不同，大體可分為剖分式、對輥式和捅桿式等幾大類。目前中國的山楂機械有剖分式山楂機、對輥式山楂機、捅桿式山楂機、打漿式山楂機、刮板式山楂機、凸齒滾筒分離凹板式山楂機幾種形式。中國山楂機械存在突出的問題有果肉損失率較高、去核后果實破損率高、機械性能不穩(wěn)定、通用性差、作業(yè)成本高、科技含量低、生產(chǎn)效率低等。1.3 山楂的特性和山楂山楂機的應(yīng)用前景山楂，是可食用植物，果核類水果，質(zhì)硬，果肉薄，味微酸澀。落葉灌木，枝密生，有細刺，幼枝有柔毛。小枝紫褐色，老枝灰褐色。能防治心血管疾病。山楂是我國特有的藥果兼用樹種。山楂的主要成分：可食用部分76%。每100g中含能量397kJ、水分73g、蛋白質(zhì)0.5g、脂肪0.6g、膳食纖維3.1g、碳水化合物22g、胡蘿卜素100g、維生素A 17g；硫胺素0.02mg、核黃素0.02mg、尼克酸0.4mg；維生素C 53mg、維生素E 7.32mg；鉀 299mg、鈉5.4mg、鈣52mg、鎂19mg、鐵0.9mg、錳0.24mg、鋅0.28mg、銅0.11mg、磷24mg、硒1.22g。含解脂酶、鞣質(zhì)等以及對大腸桿菌、綠膿桿菌、痢疾桿菌有抑制作用的成分。山楂能防治心血管疾病，具有擴張血管、強心、增加冠脈血流量、改善心臟活力、興奮中樞神經(jīng)系統(tǒng)、降低血壓和膽固醇、軟化血管及利尿和鎮(zhèn)靜作用；防治動脈硬化，防衰老、抗癌的作用。山楂酸還有強心作用，對老年性心臟病也有益處。它能開胃消食，對消肉食積滯作用更好，很多助消化的藥中都采用了山楂；山楂對子宮有收縮作用，在孕婦臨產(chǎn)時有催生之效，并能促進產(chǎn)后子宮復(fù)原；能增強機體的免疫力，有防衰老、抗癌的作用。山楂中有平喘化痰、抑制細菌、治療腹痛腹瀉的成分。近年來，隨著人民生活水平的不斷提高，人民對食品質(zhì)量的要求也越來越嚴格。生產(chǎn)廠家也意識到前處理工序?qū)Ξa(chǎn)品質(zhì)量有著不可忽視的影響，各廠家紛紛尋找合適的前處理設(shè)備。由于許多前處理設(shè)備在國內(nèi)尚屬空白，因此，開發(fā)性能優(yōu)良的山楂機及其它前處理設(shè)備是形勢所需。果核類水果主要指桃、李、杏、山楂、紅棗及橄欖等，它們在水果總產(chǎn)量中占有較大的比例。在以它們?yōu)樵霞庸わ嬃?、罐頭、果脯及果干制品時，去核作業(yè)是一項十分重要的前處理工序。以往所采用人工作業(yè)，不僅占用大量勞動力、勞動強度大、生產(chǎn)率低，并且產(chǎn)品質(zhì)量難以控制。因此，實行水果去核的機械化作業(yè)是水果加工業(yè)中必然的發(fā)展趨勢，所以山楂山楂機的應(yīng)用有非常良好的前景。2 山楂山楂機設(shè)計 如圖3所示為小型山楂山楂機，主要包括1去核刀具、2山楂定位盤、3定位盤主軸、4傳動間歇輪、5傳動圓輪、6傳動軸、7連桿、8轉(zhuǎn)盤、9擋板。其中，去核刀具能夠去掉山楂的內(nèi)核，且保證山楂不破碎；山楂定位盤能夠給山楂定位，確保去核刀具能夠準確的去掉山楂的內(nèi)核；傳動間歇輪，能夠在傳動圓輪的運轉(zhuǎn)過程中，每30轉(zhuǎn)動一下，進而使山楂定位盤間歇轉(zhuǎn)動；傳動圓輪，每轉(zhuǎn)動一圈，帶動間歇輪轉(zhuǎn)過30一次；轉(zhuǎn)動軸保證傳動圓輪平穩(wěn)傳動；連桿在轉(zhuǎn)盤圓周運動過程中，分別帶動傳動圓輪轉(zhuǎn)動和去核刀具的上下運動；轉(zhuǎn)盤做圓周運動帶動連桿運動；擋板的作用是收集去核后的山楂。山楂山楂機工作原理是：發(fā)動機發(fā)動后，通過皮帶輪把動力傳給減速器，減速器減速后帶動轉(zhuǎn)盤轉(zhuǎn)動，轉(zhuǎn)盤轉(zhuǎn)動帶動連桿做往復(fù)運動，一邊連桿帶動刀具上下運動完成山楂的去核工作，另一邊連桿帶動傳動盤，傳動盤每轉(zhuǎn)動一周，帶動間歇輪轉(zhuǎn)動一次(30)，在主軸的轉(zhuǎn)動下使山楂定位盤轉(zhuǎn)動。(當轉(zhuǎn)盤帶動連桿運動到最上方的時候，傳動的轉(zhuǎn)動裝置帶動間歇輪轉(zhuǎn)動，進而使定位盤帶動山楂轉(zhuǎn)動到刀具下方，當轉(zhuǎn)盤向下運動時，傳動裝置離開間歇輪做圓周運動，刀具在連桿作用下，向下運動完成山楂的去核工作，如此反復(fù)。山楂隨刀具向上時，遇到擋板脫落到定位盤上隨定位盤轉(zhuǎn)動，當遇到第二個擋板的時候被剝落下去，掉落到收集帶中。)2.1馬達的選擇2.1.1 選擇馬達系列馬達選擇應(yīng)保證：式中：P0馬達額定功率，kW； Pr工作機所需馬達功率，kW。所需馬達功率由下式計算：Pr=Pw/式中：Pr工作機所需有效功率，由工作機的工藝阻力及運行參數(shù)確定； 馬達到工作機的總效率，%。皮帶運輸機的PW計算方法：PW=Fv/1000 (kW)式中：F工作機的圓周力，例如運輸機上運輸帶的有效拉力，N； v工作機的線速度，例如運輸帶的帶速，m/s； D帶運輸機主動滾筒的直徑，mm； n工作機卷筒軸的轉(zhuǎn)速，r/min。按工作要求及工作條件選用三相異步馬達，封閉式結(jié)構(gòu)，電壓380V，Y系列。2.1.2 選擇馬達功率PW1=0.27 kW，1=0.990.950.960.950.9940.96=0.7698Pr1=PW/1=0.36 kWPW2=0.15 kW，2=0.950.8250.9820.990.90=0.6885Pr2=PW/2=0.22 kW 查表4.12-1，可選Y系列三相異步馬達Y802-4型，額定功率P0=0.75kW，或選Y系列三相異步馬達Y90S-4型，額定功率P0=0.75kW。 以同步轉(zhuǎn)速為1500r/min及1000r/min兩種方案進行比較，由表4.12.1查得馬達數(shù)據(jù)，計算出傳動比如下表。表1 馬達數(shù)據(jù)表方案馬達型號額定功率/kW同步轉(zhuǎn)速/(r/min)滿載轉(zhuǎn)速/(r/min)總傳動比質(zhì)量/kg 價格/元12Y802-4Y90S-40.750.7515001000139091057.9237.921823475570比較兩方案可見，方案1選用的馬達雖然質(zhì)量和價格較低，但總傳動比大。為使傳動裝置結(jié)構(gòu)緊湊，決定選用方案2。馬達型號為Y90S-4，額定功率為0.75 kW，同步轉(zhuǎn)速為1000 r/min，滿載轉(zhuǎn)速為910 r/min。由機械設(shè)計課程設(shè)計表4.12-2查得馬達中心高H = 90mm，外伸軸段D E = 24mm 50mm。2.2 傳動裝置的選擇2.2.1 傳動的選擇(1)帶傳動：帶傳動是具有中間撓性件、靠摩擦工作的傳動，如圖4所示，所以具有如下優(yōu)點：能緩沖吸振；傳動平穩(wěn)，噪聲??；過載時，帶將在帶輪上打滑，可防止其他零件損壞；結(jié)構(gòu)簡單、成本低；允許有較大的中心距(可達15m)。帶傳動的缺點：由于帶與帶輪面之間的滑動，不能保證定傳動比；在傳遞相同大小的圓周力時，結(jié)構(gòu)尺寸和軸上壓力都比嚙合傳動大；效率低、帶的壽命短。圖4 帶傳動(2)鏈傳動：鏈傳動是一種用鏈條做中間撓性件的嚙合傳動，它由鏈條、主動輪和從動輪組成，如圖5所示。鏈傳動具有如下優(yōu)點：無彈性滑動和打滑現(xiàn)象，平均傳動比準確；效率較高，0.98；結(jié)構(gòu)尺寸比較緊湊；由于不需要很大的張緊力，所以作用在軸上的載荷較??；可以在溫度較高及灰塵較大的環(huán)境下工作。圖5 鏈傳動鏈傳動的缺點：a.不能保證恒定的瞬時傳動比；b.只能用于平行軸間同向回轉(zhuǎn)的傳動；c.不適宜在載荷變化很大和急促反向的傳動中應(yīng)用；d.工作時存在噪聲；e.制造費用比帶傳動高；f.磨損鏈節(jié)伸長后運轉(zhuǎn)不穩(wěn)定，易跳齒等。(3)齒輪傳動：如圖6所示，齒輪傳動優(yōu)點主要有：a.傳動效率高；b.結(jié)構(gòu)緊湊；c.工作可靠、傳動比穩(wěn)定、壽命長。圖6 齒輪傳動齒輪傳動缺點：a.制造和安裝精度要求高；b.不宜遠距離傳動；c.成本高。綜合以上三種傳動的優(yōu)缺點，結(jié)合本設(shè)計的山楂山楂機的特點，選擇具有傳動平穩(wěn)、噪聲小、結(jié)構(gòu)簡單、成本低的帶傳動作為傳動裝置比較適合。2.2.2 V帶傳動的設(shè)計(1)選擇V帶型號 V帶傳動的功率計算公式為：Pca=KAP式中：Pca計算功率，kW； P傳遞的額定功率(如：電機的額定功率)，kW； KA 工作情況系數(shù)(表6-9)。 由表6-9查得工作情況系數(shù)KA=1.2，所以計算功率：Pca=KAP=1.20.75=9 kW 根據(jù)Pca和n1由圖6-9確定選用Z型帶。(2)確定帶輪基準直徑 由表6-7和表6-10，取主動輪基準直徑dd1=67mm。 驗算帶速：v= =6.3825(m/s) 帶速合適。 計算從動輪基準直徑dd2：dd2=idd1=2.3767=158.79 mm 根據(jù)表6-10，取dd2=160 mm。(3)確定V帶的基準長度和傳動的中心距 根據(jù)0.7(dd1+dd2)a02(dd1+dd2)，得到158.9a454。 初定中心距a0 = 350mm。 由基準長度公式：Ld=2a0+(dd1 + dd2)/2+(dd2-dd1)2/4a0Ld=2350+(67+160)/2+(160-67)2/4350=1062.7(mm) 根據(jù)表6-5選取帶的基準長度Ld=1120mm。 實際中心距aa0+(Ld-Ld)/2=350+(11201062.7/2=378.7(mm)(4)驗算主動帶輪上的包角a1a1=180-(dd2-dd1)57.3/a=165.9120主動帶輪上的包角合適。(5)確定帶的根數(shù)z 根據(jù)1=165.9，查表6-11，得Ka=0.966； 根據(jù)Ld=1120mm，查表6-5，得KL=1.08； 由n1=910r/min、i=2.37、dd1=67mm； 查表6-8a和表6-8b，得P0=0.15kW，P0=0.02kW。z=Pca/(P0+P0)KKL=0.9/(0.15+0.02)0.9661.08=5.07=6取z=6根。(6)確定帶的張緊力F0查表6-6，Z型普通V帶單位長度質(zhì)量q=0.06kg/m。F0=500Pca(2.5/K-1)/(zv)+ qv2F0=5000.9(2.5/0.966-1)/66.38+0.066.382 = 90.0(N)(6)計算帶傳動作用在軸上的載荷FQFQ=2zF0cos(r/2)=2zF0sin(1/2)式中：z帶的根數(shù)； F0單根帶的張緊力，N； 1主動帶輪上的包角，rad。FQ=2690.0sin=1071.8(N)3 山楂山楂機關(guān)鍵部件設(shè)計3.1 去核的刀具由于山楂山楂機刀具用于直接接觸山楂果實，材料的選擇應(yīng)考慮材料容易加工切削、干凈衛(wèi)生、成本低且容易清洗等特點，所以本設(shè)計選用45號鋼作為山楂定位盤的材料。查閱資料得到我國北方山楂直徑在10mm-14mm之間，根據(jù)山楂直徑本設(shè)計選取刀具的外徑為8mm，詳細尺寸如圖7。彈簧選擇不銹鋼絲（1Cr18Ni91Cr18Ni9Ti），耐腐蝕性好，工藝性好，彈簧中徑為5mm。圖7 去核的刀具3.2 山楂定位盤 3.2.1 山楂定位盤材料由于山楂山楂機屬于常用食品加工類機械，材料的選擇應(yīng)考慮到材料易得、材料容易加工切削、干凈衛(wèi)生、成本低且容易清洗等特點，所以本設(shè)計選用45號鋼作為山楂定位盤的材料。3.2.2 山楂定位盤尺寸山楂定位盤如圖8所示?？紤]到人工放置山楂的舒適度問題以及作業(yè)的工作效率，本設(shè)計采用直徑300mm的圓盤作為定位盤，圓盤上均勻分布12個直徑10mm的山楂定位孔，為了使定位盤工作穩(wěn)定可靠不產(chǎn)生傾斜本設(shè)計采用雙鍵連接軸，基孔制配合為H7。圖8 山楂定位盤3.3 山楂機定位盤主軸3.3.1 軸的材料選擇該軸的無特殊要求，選用45鋼調(diào)質(zhì)處理230-280，查表得B=640MPa。3.3.2 初步估算軸徑取軸d=20 mm。3.3.3 軸的結(jié)構(gòu)設(shè)計根據(jù)估算軸徑和軸上零件的布置，進行軸的結(jié)構(gòu)設(shè)計，確定軸上與定位盤聯(lián)接鍵截面尺寸為bh=8mm7mm配合為H7/r6。滾動軸承內(nèi)圈與軸的配合采用基孔制，軸的尺寸公差m6。在軸的兩端均制成245倒角。軸的詳細尺寸如圖9所示。圖9 定位盤主軸3.3.4 軸的強度驗算(1)主軸間歇輪上的作用力的大小轉(zhuǎn)矩：T=95.5105=95.5105=81170(Nmm)圓作用直徑：d1=39.9(mm)圓周力：Ft=2T/d1=281170/39.9=4069(N)徑向力：Fr=Ft/2.653=1534(N)軸向力：F=Ft/3.734=1090(N)(2)求垂直面上軸承的支反力及主要截面的彎矩FBV=(Fr29.5+Fd1/2)/210.5+29.5=279(N)FDV=Fr-FBV=1534-279=1255(N)截面C處彎矩為:MCV左=FBV210.5=58730(Nmm)MCV右=FDV 29.5=37023(Nmm)(3)求水平面上軸承的支反力及主要截面的彎矩FBH=Ft29.5/(210.5+29.5)=406929.5/240=500(N)FDH=Ft-FBH=4069-500=3569(N)截面C處彎矩為：MCH=FBH210.5=500210.5=105250(Nmm)(4)截面C處垂直和水平的合成彎矩(5)按彎扭合成應(yīng)力校核軸的強度進行校核時，只校核軸上承受最大彎矩和扭矩的截面的強度，由公式：式中：應(yīng)力折算系數(shù)； Mv軸上危險截面處的當量彎矩，Nmm； W 軸上危險截面處的抗彎矩截面系數(shù)，mm3； -1 軸在對稱循環(huán)狀態(tài)下的許用彎曲應(yīng)力,MPa，見表11-1； d 軸上危險截面處直徑，mm。當此段軸上有一個鍵槽時，直徑應(yīng)加大3%；有兩個鍵槽時，應(yīng)加大7%。取=0.6，計算截面上的應(yīng)力：前面已選定軸的材料為45鋼，調(diào)質(zhì)處理，由表11-1查得-1=60MPa，由于v-1，故安全。3.4 山楂機主軸間歇輪山楂山楂機主軸間歇輪如圖10所示，材料選用容易加工的45號鋼，該輪總直徑100mm，確定軸上與定位盤聯(lián)接鍵截面尺寸為bh=8mm7mm配合為H7/r6，間歇輪與軸的配合采用基孔制，軸的尺寸公差為r6，粗糙度要求為1.6。圖10 山楂機主軸間歇輪3.5 山楂機傳動圓盤山楂山楂機傳動圓盤如圖11所示，材料選擇45號鋼，傳動圓盤外圓直徑為70mm，確定軸上與傳動盤聯(lián)接鍵截面尺寸為bh=6mm6mm配合為H7/r6。傳動圓盤與軸的配合采用基孔制，軸的尺寸公差r6，傳動圓盤孔的粗糙度1.6，其余6.3。圖11 山楂機傳動圓盤3.6 山楂機傳動盤的軸圖12 定位盤主軸3.6.1 軸的材料選擇該軸的無特殊要求，選用45鋼調(diào)質(zhì)處理230-280，查表得B=640MPa。3.6.2 初步估算軸徑取軸d = 20 mm。3.6.3 軸的結(jié)構(gòu)設(shè)計根據(jù)估算軸徑和軸上零件的布置，進行軸的結(jié)構(gòu)設(shè)計，確定軸上與傳動盤聯(lián)接鍵截面尺寸為bh=6mm6mm配合為H7/r6。滾動軸承內(nèi)圈與軸的配合采用基孔制，軸的尺寸公差m6。在軸的兩端均制成245倒角。軸的詳細尺寸如圖12所示。3.6.4 軸的強度驗算(1)主軸間歇輪上的作用力的大小轉(zhuǎn)矩：T=95.5105=95.5105=83140(Nmm)圓作用直徑：d1=26(mm)圓周力：Ft=2T/d1=283140/26=6395(N)徑向力：Fr=Ft/2.653=2311(N)軸向力：F=Ft/3.734=1613(N)(2)求垂直面上軸承的支反力及主要截面的彎矩FBV=(Fr51.5+Fd1/2)/182+51.5=820(N)FDV=Fr-FBV=2311-820=1491(N)截面C處彎矩為:MCV左=FBV182=74620(Nmm)MCV右=FDV 51.5=38368(Nmm)(3)求水平面上軸承的支反力及主要截面的彎矩FBH=Ft51.5/(182+51.5)=639551.5/233.5=1410(N)FDH=Ft-FBH=6395-1410=4985(N)截面C處彎矩為：MCH=FBH210.5=1410182=128310 (Nmm)(4)截面C處垂直和水平的合成彎矩(5)按彎扭合成應(yīng)力校核軸的強度進行校核時，只校核軸上承受最大彎矩和扭矩的截面的強度，由公式：式中：應(yīng)力折算系數(shù)； Mv軸上危險截面處的當量彎矩，Nmm； W 軸上危險截面處的抗彎矩截面系數(shù)，mm3； -1 軸在對稱循環(huán)狀態(tài)下的許用彎曲應(yīng)力,MPa，見表11-1； d 軸上危險截面處直徑，mm。當此段軸上有一個鍵槽時，直徑應(yīng)加大3%；有兩個鍵槽時，應(yīng)加大7%。取=0.6，計算截面上的應(yīng)力：前面已選定軸的材料為45鋼，調(diào)質(zhì)處理，由表11-1查得-1=60MPa，由于v-1，故安全。3.7 軸承選擇設(shè)計機械時，應(yīng)根據(jù)載荷情況、轉(zhuǎn)速高低、空間位置、調(diào)心性能以及其他要求，選定合適的滾動軸承類型。具體選擇時可參考下列原則。3.7.1 載荷條件軸承所受載荷的大小、方向和性質(zhì)，是選擇軸承類型的主要依據(jù)。當軸承承受純徑向載荷時，應(yīng)選用向心軸承。當承受純軸向載荷且轉(zhuǎn)速不很高時，宜采用推力軸承；如轉(zhuǎn)速很高，則因離心力使?jié)L動體與保持架之間的壓力增大，摩擦加劇而使壽命顯著縮短，此時應(yīng)選用角接觸球軸承。當同時承受徑向載荷和軸向載荷時，如果以徑向載荷為主，可選用深溝球軸承或接觸角較小的角接觸軸承；以軸向載荷為主，可選擇接觸角較大的角接觸軸承，也可采用向心軸承和推力軸承組合在一起的方式，分別承受徑向載荷和軸向載荷。3.7.2 軸承轉(zhuǎn)速一般來講，軸承轉(zhuǎn)速較高時，應(yīng)優(yōu)先選用球軸承。在內(nèi)徑相同的情況下，外徑愈小，則滾動體愈小，運轉(zhuǎn)時，滾動體的慣性離心力也就愈小，因而適于在更高的轉(zhuǎn)速下工作。因此，在高速條件下，宜選用外徑和滾動體較小的軸承。此外，軸承的接觸角越小，其座圈承受滾動體慣性離心力的條件越好，所以，在高速性能方面，接觸角a為零的向心軸承優(yōu)于角接觸軸承和推力軸承。3.7.3 調(diào)心性能當軸在工作時彎曲變形較大，或軸的跨距較大，或軸承座制造安裝精度較低時，則要求軸承內(nèi)、外圈能有一定的相對角位移，此時應(yīng)采用調(diào)心軸承。3.7.4 軸承剛度一般情況下，滾子軸承的剛度比球軸承高，在要求軸承剛度高的場合，應(yīng)選用滾子軸承。3.7.5 安裝及拆卸要求在需要經(jīng)常裝拆或裝拆困難的場合，可選用內(nèi)、外圈可分離的軸承，如圓柱滾子軸承、圓錐滾子軸承。3.7.6 經(jīng)濟性一般地說，球軸承比滾子軸承價格便宜，向心軸承比角接觸軸承便宜。軸承的精度等級越高，其價格就越貴。因此，選用高精度軸承時應(yīng)慎重。根據(jù)以上所述，結(jié)合本設(shè)計經(jīng)濟實用的特點，選擇軸承型號為6204的深溝球軸承為本設(shè)計所使用軸承。3.7.7 軸承壽命所選軸承型號為6905ZZ和6902ZZ的深溝球軸承。(1)求兩軸承的計算軸向力和。軸承6905ZZ軸向力， 取e0.42。NNNN 由插值法計算得、再計算NNNN確定 、 ，N、N(2)求軸承當量動載荷和。分別進行查表或插值計算得徑向載荷系數(shù)和軸向載荷系數(shù)：軸承1 軸承2 X2=1 因軸承運轉(zhuǎn)中有中等沖擊載荷，按表13.6 取NN(3)驗算軸承壽命。因為所以按軸承1得受力大小驗算：h已知本機器使用10年，一班制，預(yù)期壽命為：h故本軸承能夠滿足設(shè)計要求3.8 連桿山楂山楂機連桿如圖13所示，材料選擇45號鋼。圖13連桿3.9 山楂去核機裝配圖（圖14）圖14 山楂去核機裝配圖4 結(jié)論 設(shè)計目的；主要研究內(nèi)容；結(jié)果和結(jié)論 我國目前的山楂山楂機械的發(fā)展情況比較落后，由于缺少良好的設(shè)備，加工手段落后，生產(chǎn)效率低，致使一些地區(qū)出現(xiàn)水果積壓腐爛現(xiàn)象，給果農(nóng)造成很大的經(jīng)濟損失。山楂去核手工作業(yè)現(xiàn)在在中國仍然是主要的加工手段，不僅占用大量的勞動力、勞動強度大、生產(chǎn)率低，而且衛(wèi)生安全也得不到有效保障，大力推進山楂去核的機械化進程是社會發(fā)展的需要。山楂山楂機不但提高了生產(chǎn)效率，而且安全衛(wèi)生也能夠得到有效的加強。山楂去核在整個山楂加工工序中，不僅勞動強度大，而且人工作業(yè)生產(chǎn)效率低，安全衛(wèi)生達不到要求。所以考慮中國目前的情況，設(shè)計了這種小型山楂山楂機，我設(shè)計的山楂山楂機生產(chǎn)效率得到了顯著的提高，山楂破損率低，同時安全衛(wèi)生的問題也得到了有效的解決。本山楂山楂機是根據(jù)山楂的物理特性，結(jié)合目前山楂山楂機的現(xiàn)狀，運用所學(xué)機械原理、機械設(shè)計等相關(guān)知識，進行的相關(guān)設(shè)計。由于沒有加工制作樣機，山楂山楂機的運行狀況未進行實驗。參考文獻1劉暢，宿敬.山楂機的發(fā)展現(xiàn)狀J.黑龍江科技信息.2009(33)：136-1392陳佳，宋少江.果核類山楂機的研究進展J.中藥研究與信息.2005(07)：121-1273陳芳.中心定位式果核類山楂機的設(shè)計J.糧油加工與食品機械.1997(05)：56-594金瑩，何蔚娟，張秀軍.果核類水果山楂機現(xiàn)狀的分析J.中國農(nóng)村小康科技.2005(03)：83-875陳芳，劉法治，鄧春巖.去核定位機理的研究與定位機構(gòu)的初步設(shè)計J.河南職技師院學(xué)報.1999(01)：123-1266李明，連文偉，鄧干然.我國果核類水果山楂機具的現(xiàn)狀及亟待研究的技術(shù)問題探討J.糧油加工與食品機械.1999(03)：56-597陳芳，鄧春巖，鄭玉才.山楂山楂機的結(jié)構(gòu)設(shè)計J.河北農(nóng)業(yè)技術(shù)師范學(xué)院學(xué)報.1997(02)：74-778王群，邵長發(fā).水果去核(去芯)機械的現(xiàn)狀及發(fā)展前景J.包裝與食品機械.1993(03)：156-1599李明，鄧干然，連文偉，連仕華.龍眼鮮果剝殼脫核機的試驗研究J.農(nóng)業(yè)工程學(xué)報.1999(02)：35-3910王富華.我國食品標準現(xiàn)狀、問題及建議J.湖北農(nóng)業(yè)科學(xué).1999(06)：45-4911馬草.果類系列食品的加工J.四川食品與發(fā)酵.1995(01)：95-9812R.W 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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).