水果單列輸送裝置的設(shè)計(jì)
水果單列輸送裝置的設(shè)計(jì),水果單列輸送裝置的設(shè)計(jì),水果,生果,瓜果,單列,輸送,裝置,設(shè)計(jì)
畢業(yè)設(shè)計(jì)任務(wù)書(shū)
設(shè)計(jì)課題
名稱(chēng)
水果單列輸送裝置的設(shè)計(jì)
學(xué)生姓名
黃銳
院（系）
工程
專(zhuān)業(yè)班級(jí)
機(jī)051
指導(dǎo)教師
劉木華
職稱(chēng)
教授
學(xué)歷
博士后
畢業(yè)設(shè)計(jì)要求：
1.完成電子文檔及答辯的PPT文檔。并打印裝訂成冊(cè)；
2.繪制零件圖和裝配圖，圖紙量不少于1.5A0；
3.按時(shí)認(rèn)真完成畢業(yè)設(shè)計(jì)內(nèi)容；
4.查閱相關(guān)文獻(xiàn)和資料，擴(kuò)展知識(shí)面。
畢業(yè)設(shè)計(jì)內(nèi)容與技術(shù)參數(shù)：
1.水果單列輸送裝置的零部件設(shè)計(jì);
2.繪制零件圖裝配圖，寫(xiě)說(shuō)明書(shū);
3.按照技術(shù)參數(shù)計(jì)算并確定機(jī)體各零部件的結(jié)構(gòu)尺寸；
4.配以圖表達(dá)清楚內(nèi)容。
畢業(yè)設(shè)計(jì)工作計(jì)劃：
1、2008年12月 接受畢業(yè)設(shè)計(jì)任務(wù)，查閱資料為任務(wù)做準(zhǔn)備；
2、2009年 1月 確定整體方案；
3、2009 年2月～4月 繪制圖紙及編寫(xiě)說(shuō)明書(shū)
4、2009 年5月 整理圖紙及說(shuō)明書(shū)文件定稿打印，準(zhǔn)備畢業(yè)答辯。
接受任務(wù)日期： 2008 年 月 日 要求完成日期： 2009 年 月 日
學(xué) 生 簽 名：
指導(dǎo)教師簽名： 院長(zhǎng)（主任）簽名：
編 號(hào) 20050657
畢業(yè)設(shè)計(jì)材料
題 目
水果單列輸送裝置的設(shè)計(jì)
專(zhuān) 業(yè)
機(jī)械化及其自動(dòng)化
學(xué)生姓名
黃銳
材 料 目 錄
序號(hào)
附 件 名 稱(chēng)
數(shù)量
備注
1
畢業(yè)設(shè)計(jì)說(shuō)明書(shū)
1
2
畢業(yè)設(shè)計(jì)任務(wù)書(shū)
2
3
CAD圖紙A0
1
4
CAD圖紙A3
1
5
CAD圖紙A4
7
二〇〇九年五月
畢業(yè)論文題目
7
本 科 畢 業(yè) 設(shè) 計(jì)
題目： 水果單列輸送裝置設(shè)計(jì)
學(xué) 院： 工 學(xué) 院
姓 名： 黃 銳
學(xué) 號(hào)： 20050657
專(zhuān) 業(yè)： 機(jī)械化及其自動(dòng)化
年 級(jí)： 機(jī)051
指導(dǎo)教師： 劉木華
二OO九年 五 月
13
水果單列輸送裝置設(shè)計(jì)
摘 要
該設(shè)計(jì)的水果單列輸送裝置是一種能實(shí)現(xiàn)水果自動(dòng)形成單列的裝置。將兩個(gè)筒式滾子通過(guò)形成V字形的方式放置在機(jī)器的兩邊（從水果輸送進(jìn)來(lái)到輸送出去的方向），滾筒利用電機(jī)帶動(dòng)，當(dāng)電機(jī)運(yùn)轉(zhuǎn)時(shí)，帶動(dòng)主動(dòng)滾筒。主動(dòng)滾筒通過(guò)皮帶的轉(zhuǎn)動(dòng)帶動(dòng)從動(dòng)滾筒轉(zhuǎn)動(dòng)。前后兩對(duì)滾筒的運(yùn)轉(zhuǎn)速率不同，水果則可能原地不動(dòng)或者運(yùn)動(dòng)離開(kāi)。形成旋渦狀分開(kāi)，所以在滾子兩邊設(shè)有坡型板，在坡型板的輔助下，類(lèi)球形水果能自動(dòng)形成單列進(jìn)入下一級(jí)機(jī)器中。在電機(jī)的驅(qū)動(dòng)下。滾子可以平穩(wěn)的運(yùn)轉(zhuǎn)。能夠確保正確及可靠的供給水果、能夠?yàn)槎喾N無(wú)聊自動(dòng)成單列運(yùn)輸。從而滿足特定工序的需求。例如用于水果噴蠟及拋光、水果分級(jí)、其他準(zhǔn)球形物料的分級(jí)等裝備所需的供給機(jī)構(gòu)。
關(guān)鍵詞：水果 單列輸送 水果分級(jí)
Abstract
The design of the fruit is a single delivery device to achieve the formation of separate fruit and automatic devices. The two roller tube through the formation of V-shaped manner on both sides of the machine placed in (from the fruit conveyor to come out of the direction of transmission), the use of motor driven rollers, when the motor running, the drive roller initiative. Take the initiative to drum through the drive belt driven rotating drum rotation. Two pairs of rollers before and after the operation rate of different fruit may stay put or leave the campaign. The formation of vortex-like separated, it has a roller on both sides of the slope plate, in the slope of the supporting plate, the type of spherical fruits automatically to form a separate machine to the next level.
Driven by the motor. Roller can be a smooth operation. To ensure correct and reliable supply of fruit, can be automated for a variety of boring into a single transport. Processes to meet specific needs. For example, spray wax and polishing fruit, fruit grading, and other quasi-spherical, such as materials and equipment required for the classification of supply agencies.
Key words: fruits, fruit grading conveyor separate
Translated text 目 錄
1 緒 論 1
1.1 引言 1
1.2 水果分級(jí)機(jī)器的市場(chǎng) 1
1.3 水果分級(jí)的意義 1
2零部件的設(shè)計(jì)與選擇 2
2.1框架主體的設(shè)計(jì) 2
2.2輸送帶的選擇 3
2.3滾筒的設(shè)計(jì) 4
2.4電機(jī)承載的設(shè)計(jì) 5
2.5皮帶托板與滾筒軸撐架的設(shè)計(jì) 5
2.6滾筒支承座的設(shè)計(jì) 6
2.7 軸的設(shè)計(jì) 6
2.8 坡形板的設(shè)計(jì) 7
2.8滾筒中軸承的選擇 7
2.9電動(dòng)機(jī)的選擇 8
2.10輪子的選擇 8
3輸送機(jī)械的計(jì)算 9
3.1工作條件 9
3.2輸送能力的計(jì)算 9
3.3電動(dòng)機(jī)帶輪的計(jì)算 9
3.4滾筒軸軸承的計(jì)算 9
3.5軸的強(qiáng)度計(jì)算 10
總結(jié) 11
參考文獻(xiàn)
致 謝
1 緒 論
1.1 引言
當(dāng)代生活中，人們對(duì)果品的要求是不只是實(shí)用，而且要外觀好看。包裝精美。故此水果分級(jí)機(jī)器營(yíng)運(yùn)而生，水果分級(jí)機(jī)器的目的是為了把水果按照外形，尺寸，重量按等級(jí)分開(kāi)來(lái)，已達(dá)到產(chǎn)生更多利潤(rùn)的目的。
本種水果分級(jí)機(jī)，由機(jī)架、整理排列皮帶輸送機(jī)及裝于其上的前段整理排列裝置、檢測(cè)分選皮帶輸送機(jī)及裝于其上的對(duì)射式光電傳感器光電檢測(cè)裝置和以壓縮空氣為動(dòng)力的噴氣頭自動(dòng)選別裝置組成；傳感器和噴氣頭之間有控制線電連接；整理排列皮帶輸送機(jī)的出料端接檢測(cè)分選皮帶輸送機(jī)進(jìn)料端；前段整理排列裝置為底部有出口的無(wú)底框形結(jié)構(gòu)，水果直接堆放在皮帶上?？啥沤^機(jī)械分級(jí)易造成傷果現(xiàn)象的發(fā)生，適應(yīng)性好，對(duì)硬皮類(lèi)、表皮薄弱的水果同樣適用；且調(diào)整靈活，分級(jí)精度高，不會(huì)出現(xiàn)大小“串級(jí)”的混亂現(xiàn)象。
1.2 水果分級(jí)機(jī)器的市場(chǎng)
近20年來(lái)，世界水果生產(chǎn)高速發(fā)展，總產(chǎn)量從80年代初的年產(chǎn)2．7億t到1999年則達(dá)到5．35億t。在供求關(guān)系上，名優(yōu)水果及果汁消費(fèi)量迅速增長(zhǎng)，水果需求種類(lèi)多樣化趨勢(shì)明顯。在區(qū)域分布上，南半球諸國(guó)的參與促進(jìn)了水果的周年供應(yīng)，發(fā)展中國(guó)家的參與大大增加了熱帶水果的供給，亞洲是水果生產(chǎn)和消費(fèi)增長(zhǎng)速度最快的地區(qū)，也是目前水果產(chǎn)量最多的地區(qū)
水果分級(jí)現(xiàn)在已經(jīng)成為市場(chǎng)中水果流通環(huán)節(jié)所必須的一個(gè)項(xiàng)目，是現(xiàn)在廣泛的應(yīng)用于各個(gè)大型果園及個(gè)人小型果園的的必要機(jī)械。起著實(shí)現(xiàn)各生產(chǎn)環(huán)節(jié)的連續(xù)性和自動(dòng)化的作用，大大提高了勞動(dòng)生產(chǎn)率，減輕了勞動(dòng)強(qiáng)度。與傳統(tǒng)的人工分級(jí)相比，具有工作平穩(wěn)可靠，操作維護(hù)方便，避免傷害果皮，輸送距離長(zhǎng)，提高工作效率，運(yùn)轉(zhuǎn)費(fèi)用低等優(yōu)點(diǎn)。
根據(jù)目前的水果市場(chǎng)的需求，用機(jī)器水果分級(jí)成為果園的頭等需求，為了贏取更多的利潤(rùn)空間，水果分級(jí)機(jī)器是比人工分級(jí)更好的選擇。
1.3 水果分級(jí)的意義
水果分級(jí)是根據(jù)水果的尺寸，色澤。和重量分級(jí)，分級(jí)的目的是便于使每一種不同的水果形成自己的經(jīng)濟(jì)效益。例如：按照尺寸分類(lèi)，可以將大小一致的水果聚集到一起，然后再按色澤分類(lèi)。最后裝成果盒。以此提高水果的價(jià)值，比單一大批的進(jìn)行水果出售可以賺取更多的利潤(rùn)。而一些色澤不勻稱(chēng)，重量。大小不一的水果則可以進(jìn)行加工，制成罐頭或者水果附加產(chǎn)品。提高水果的價(jià)值。為水果種植戶提供更豐厚的利潤(rùn)。也為不同的水果需求人群提供更加多變的選擇。
2零部件的設(shè)計(jì)與選擇
2.1框架主體的設(shè)計(jì)
框架主體做為支撐和連接各個(gè)部件的部分。根據(jù)需要，考慮到本機(jī)器一般是為小型果園準(zhǔn)備的，從價(jià)格和經(jīng)濟(jì)性方面選取，故選取鋁型材。而擠壓好的鋁合金型材，其表面耐蝕性不強(qiáng)，須通過(guò)陽(yáng)極氧化進(jìn)行表面處理以增加鋁材的抗蝕性、耐磨性及外表的美觀度（鋁型材就是鋁棒通過(guò)熱熔,擠壓.從而得到不同截面形狀的鋁材料）。
如圖1所示：
考慮到支撐的重量和性能因素，取直徑是50mm的型材截面。具體尺寸見(jiàn)裝配圖。框架之間的連接采用一固定零件與螺母共同固定在鋁型材四面的槽中。固定零件。 圖2：角固定件
材料選擇為15號(hào)不需無(wú)工藝要求。
2.2輸送帶的選擇
輸送帶用來(lái)傳遞牽引力和承放被運(yùn)貨物，因此要求它強(qiáng)度高、抗磨耐用、伸長(zhǎng)率小和便于安裝修理。帶式輸送機(jī)使用的輸送帶有橡膠帶、塑料帶、鋼帶、金屬網(wǎng)帶等，最常用的是橡膠帶。橡膠輸送帶有棉織芯，合成纖維芯，鋼絲繩芯等多種。塑料輸送帶有層芯和整芯之分。各種芯材和不同的覆蓋膠可組成各種類(lèi)型的光面或花紋輸送帶。
在進(jìn)行系統(tǒng)設(shè)計(jì)時(shí)，應(yīng)認(rèn)真研究輸送量，輸送距離，輸送速度及輸送帶寬度之間的關(guān)系。
根據(jù)輸送帶的工作條件，合理確定安全系數(shù)，經(jīng)濟(jì)合理的選擇輸送帶的帶芯材料和帶芯層數(shù)。輸送帶的安全系數(shù)應(yīng)考慮安全，可靠，壽命，制造質(zhì)量，經(jīng)濟(jì)成本，接頭效率，啟動(dòng)系數(shù)，現(xiàn)場(chǎng)條件，使用經(jīng)驗(yàn)等因素。
本機(jī)器中運(yùn)送的物料為水果。選取滌綸帆布的輸送帶， PP-90型。滌綸帆布厚度為1.0mm，扯斷強(qiáng)度為90N/(mm·層)，層數(shù)為1.上下覆蓋膠厚度為0.5mm。輸送帶厚度為2.0mm。重量為1.35kg/㎡。輸送帶寬取100mm.所以選擇兩對(duì)滾筒承載輸送帶處寬度為104mm，其他尺寸詳見(jiàn)零件圖
輸送帶的厚度 輸送帶厚度（mm）=布層數(shù)×每層厚度（mm）+上厚膠（mm）+下厚膠（mm）
輸送帶的最大張緊工作張力：=
式中---輸送帶的最大工作張力，N
B---帶寬，mm
Z---輸送帶的芯層帆布層數(shù)；
---輸送帶縱向扯斷強(qiáng)度，N/(mm·層)
n---輸送帶的安全系數(shù)。
表1
計(jì)算項(xiàng)目
符號(hào)
單位
計(jì)算公式和參數(shù)選定
計(jì)算結(jié)果
計(jì)算功率
W
500
帶 速
m/s
0.3
初定中心距
m
根據(jù)結(jié)構(gòu)而定
1700
單位帶寬離心拉力
N/m
1.6
帶寬
m
0.1
作用在軸上的力
N
1666.7
2.3滾筒的設(shè)計(jì)
傳動(dòng)滾筒一般為傳送機(jī)構(gòu)的主要部件。滾筒表面有裸露光鋼面，人字形和菱形花紋橡膠覆面，小功率。小帶寬及環(huán)境干燥時(shí)可采用裸露光鋼面滾筒。本設(shè)計(jì)中即選擇了裸露光鋼面滾筒。而滾筒表面要求精度不高，與皮帶間產(chǎn)生摩擦力使輸送帶不至于打滑即可。但在輸送帶繞過(guò)滾筒處又會(huì)使輸送帶發(fā)生疲勞磨損。所以滾筒直徑不能太小，本機(jī)器中有兩對(duì)滾筒。一對(duì)為主動(dòng)滾筒。一對(duì)為從動(dòng)滾筒。主動(dòng)滾筒中有V帶槽。從動(dòng)滾筒為對(duì)稱(chēng)結(jié)構(gòu)。兩對(duì)滾筒均用滾動(dòng)軸承內(nèi)襯（軸承選擇見(jiàn)下面）。因?yàn)闄C(jī)械為水平傳送所以?xún)蓚€(gè)的直徑可以相同。僅是在是否有V槽方面不同。
圖3.從動(dòng)滾筒 圖4.主動(dòng)滾筒
2.4電機(jī)承載的設(shè)計(jì)
定在托板上。故要求此支撐板有一般的負(fù)載的支撐能力。另外電機(jī)震動(dòng)較大，。要求有一定的延伸率和強(qiáng)度，易于沖壓和焊接，故選用30做為托板材料。因?yàn)殡姍C(jī)帶動(dòng)兩個(gè)滾筒的運(yùn)動(dòng)是呈V字狀態(tài)，所以電機(jī)支撐板也呈V狀。
圖5電機(jī)承載板
2.5皮帶托板與滾筒軸撐架的設(shè)計(jì)
在皮帶下面安裝一托板，托板的作用是用于支承傳送帶及輸送帶上的所承載的物料，保證輸送帶穩(wěn)定運(yùn)行的裝置。
因?yàn)榇藱C(jī)器主要分級(jí)的為橙子一類(lèi)的低重量水果。（即使在機(jī)器上放滿橙子也只有10KG的重量。）選取兩節(jié)式槽型輸送機(jī)比較方便。在兩傳送帶間放置一皮帶托板即可，
圖6后藍(lán)色的為滾筒支撐架
皮帶托板可選擇08承受一般載荷的材料，因?yàn)橛昧坎欢唷?
輸送帶從此V板上下穿過(guò)，則輸送帶可以利用板的承載能力承受橙子的重量。
滾筒支撐架主要是用來(lái)放置滾筒并且支撐皮帶支撐架的。承受一般大小的力。而在形狀上需要呈現(xiàn)V字形，并且兩端有固定伸出，為焊接件。因?yàn)樵跈C(jī)器上受輕負(fù)荷。磨損無(wú)關(guān)緊要，而且要求的機(jī)械性能不高，材料選擇45鋼。
圖6水果托板
2.6滾筒支承座的設(shè)計(jì)
滾筒為固定在滾筒支承座上，并且滾筒支承座固定在滾筒支撐架上，因?yàn)橛?對(duì)從動(dòng)輪。所以做2對(duì)滾筒支承座，用以固定滾筒。底板和旁邊支架為焊接，
材料選擇為30無(wú)特殊要求。滾筒支撐座尺寸詳見(jiàn)裝配圖。 圖7滾筒支撐架
2.7 軸的設(shè)計(jì)
軸的材料一般是經(jīng)過(guò)軋制或鍛造的碳素鋼或合金鋼，有條件的可直接用冷拔鋼材。根據(jù)需要，一般軸要經(jīng)過(guò)熱處理或表面強(qiáng)化處理。以提高其力學(xué)性能及耐磨性等，在一般溫度下合金鋼和碳鋼的彈性模量相差很小，故采用合金鋼不能提高軸的剛度。
本設(shè)計(jì)中主要是滾筒處采用軸，考慮到是輸送水果，故對(duì)于軸的各方面要求不高。而且為滾筒轉(zhuǎn)，軸不轉(zhuǎn)的方式。所以選取鋼45，因?yàn)檩S的直徑尺寸小于100mm，所以用正火處理，硬度為170~217.。
2.8 坡形板的設(shè)計(jì)
在整體機(jī)械中安裝左右兩個(gè)坡形板，在坡形板的輔助下。水果可以聚攏在中間。并且可以形成一列，輸送到下一機(jī)構(gòu)中，進(jìn)行分級(jí)，達(dá)到水果分級(jí)的目的。
圖8 坡形板
后蓋板的作用是阻止水果落出裝置外面，而且在機(jī)械上方可以掀開(kāi)蓋板方便維修。
圖9后蓋板
2.8滾筒中軸承的選擇
通過(guò)與滑動(dòng)軸承的對(duì)比，滾動(dòng)軸承油如下優(yōu)點(diǎn)：
1. 摩擦系數(shù)小，能使機(jī)器靈活輕快的旋轉(zhuǎn)，提高工作效率。
2. 滾動(dòng)軸承一般都是鋼材制造的。因此經(jīng)久耐用。
3. 滾動(dòng)軸承的尺寸標(biāo)準(zhǔn)化，不像滑動(dòng)軸承在更換時(shí)需要裝配，因此安裝盒拆卸比較
方便。
缺點(diǎn)是滾動(dòng)軸承沖擊負(fù)荷的能力較差，因?yàn)槭钦w的，安裝在長(zhǎng)軸的中部困難，徑向向尺寸比滑動(dòng)軸承大，而且在高速運(yùn)轉(zhuǎn)時(shí)聲響較大。
但是這些缺點(diǎn)不影響滾動(dòng)軸承在本機(jī)器中的使用。
2.9電動(dòng)機(jī)的選擇
機(jī)選用的是型號(hào)為MBW07，功率為0.75千瓦的減速電動(dòng)機(jī)。
2.10輪子的選擇
本設(shè)計(jì)中選擇的輪子為平板式腳輪，輪子直徑為130mm型號(hào)為ZP130WS2-160
3輸送機(jī)械的計(jì)算
3.1工作條件
考慮到本機(jī)器為一般小型果園所用，所以可以放在房間中，工作環(huán)境為室內(nèi)，并且可以保持干燥。環(huán)境溫度為室溫，水果的來(lái)源一般是由上一級(jí)輸送裝置送來(lái)，隱藏避免了大量卸料，即可以控制水果來(lái)源的速度。
3.2輸送能力的計(jì)算
成件物品的輸送能力= （kg/s）
式中 G----單件物品質(zhì)量，kg;
T----物品在輸送機(jī)上的間距，m;
v----帶速，m/s.
每小時(shí)的輸送的件數(shù)：n=3600
3.3電動(dòng)機(jī)帶輪的計(jì)算
帶輪直徑小可以使傳動(dòng)尺寸進(jìn)場(chǎng)，但是直徑過(guò)小，會(huì)使帶的彎曲應(yīng)力過(guò)大，壽命降低，所以帶輪的尺寸要適中。V帶的設(shè)計(jì)主要是要求質(zhì)量小，結(jié)構(gòu)工藝性能好。無(wú)過(guò)大的鑄造內(nèi)應(yīng)力，質(zhì)量均勻分布。轉(zhuǎn)速高時(shí)要經(jīng)過(guò)動(dòng)平衡，輪槽的功過(guò)面粗糙度合理。以減少帶的磨損，輪槽尺寸和槽面角應(yīng)保持一定的精度。以使載荷分布較為均勻等。帶輪的主要材料是鑄鐵。常用牌號(hào)為HT150,HT200,最大的圓周速度為25m/s.
=(1.8-2)d.d為軸的直徑
C’=(1/7-1/4)B
=0.8
s=c’
帶傳動(dòng)查手冊(cè)選擇Y型的直徑為25mm的小帶輪。選擇實(shí)心式的帶輪、
為了考慮后一級(jí)機(jī)器的分級(jí)能力，所以考慮大約每秒鐘走過(guò)的水果大概是直徑為60mm的水果5個(gè)左右。
單列水果輸送則是兩根皮帶的速度不同。假設(shè)一邊v=50r/s則通過(guò)輸送能力公式得出，另邊的輸送速度為100r/s，
3.4滾筒軸軸承的計(jì)算
滾動(dòng)軸承的摩擦主要有：滾動(dòng)體與滾道之間的滾動(dòng)摩擦和滑動(dòng)摩擦；保持架與滾動(dòng)體及套圈引導(dǎo)面之間的滑動(dòng)摩擦；滾子端面和套圈當(dāng)邊之間的摩擦；潤(rùn)滑劑的粘性阻力；密封裝置的滑動(dòng)摩擦等。其大小取決與軸承的類(lèi)型，尺寸，負(fù)荷，轉(zhuǎn)速，潤(rùn)滑，密封等因素。軸承的摩擦力矩一般可按照如下公式計(jì)算：
M=
式中 M——軸承的摩擦力矩， ；
——軸承摩擦系數(shù)；
F——軸承負(fù)荷（），N；
d——軸承內(nèi)徑，mm.
根據(jù)計(jì)算比較，本機(jī)器選擇單列向心球軸承，查機(jī)械手冊(cè)選擇101型特輕（1）系列。
基本尺寸為d=15，D=32，B=8，mm
基本額定負(fù)載C=4.32，C=2.50 kN
極限轉(zhuǎn)速 脂18000，油24000r/min
重量W≈0.025
軸承型號(hào)7000102，
其他尺寸r=0.3
安裝尺寸dmin=0.3，Dmax=29.6，rmax=0.3 mm
3.5軸的強(qiáng)度計(jì)算
滾筒中所選用的軸為實(shí)心軸，按扭轉(zhuǎn)強(qiáng)度計(jì)算有公式：d=17.2=A
d—軸端直徑，mm
T—軸所傳遞的扭矩，N·m T=9550
P—軸所傳遞的功率，KW
n—軸的工作轉(zhuǎn)速，r/min
[]許用扭轉(zhuǎn)剪應(yīng)力，N / 查機(jī)械設(shè)計(jì)手冊(cè)中表6-1-3選取
[]許用扭轉(zhuǎn)角，（°）/m查機(jī)械設(shè)計(jì)手冊(cè) 表6-1-4
A— 系數(shù)，查機(jī)械設(shè)計(jì)手冊(cè)中表6-1-3選取
B— 系數(shù)，查機(jī)械設(shè)計(jì)手冊(cè) 表6-1-4選取
表2
軸的材料
Q235——A.20
Q275 35
1Cr18Ni9Ti
45
40Cr,35SiMn,42SiMn
[],N /
15-25
20-35
25-45
35-55
A
149-126
135-112
126-103
112-97
總結(jié)
在當(dāng)今生活中，機(jī)械越來(lái)越多的進(jìn)入當(dāng)代人的生活中，當(dāng)大家都離不開(kāi)機(jī)械的時(shí)候，人們就要努力去完善我們的機(jī)械，或者說(shuō)，要進(jìn)一步開(kāi)發(fā)機(jī)械的更多的能力。
在現(xiàn)代人用水果滿足自己口腹之欲的時(shí)候，水果的附加價(jià)值也得到充分的重視?；蛘哒f(shuō)水果的禮品價(jià)值，所以這臺(tái)機(jī)器應(yīng)運(yùn)而生。
在本機(jī)機(jī)械的設(shè)計(jì)當(dāng)中，我設(shè)計(jì)的部分主要是水果輸送過(guò)程中水果單列輸送，在設(shè)計(jì)過(guò)程中，了解到了很多關(guān)于水果分級(jí)的優(yōu)點(diǎn)，也學(xué)習(xí)到了許多運(yùn)動(dòng)原理。例如本機(jī)器中，前一個(gè)裝置是將大批量水果運(yùn)送上來(lái)。但是大批量水果無(wú)法分級(jí)，則通過(guò)本裝置進(jìn)行分級(jí)裝置當(dāng)中的兩個(gè)傳送帶的速度不同，則此裝置即可以使水果在不同位置有不同的速度，再通過(guò)速度不同，進(jìn)行旋轉(zhuǎn)。從而使水果摩擦之后形成單列，方便下一級(jí)的機(jī)構(gòu)進(jìn)行分級(jí)。
此裝置可以運(yùn)用到實(shí)際的生產(chǎn)生活中，產(chǎn)生經(jīng)濟(jì)效益。
在遇到了很多書(shū)本上知識(shí)無(wú)法解決的問(wèn)題，通過(guò)解決問(wèn)題，學(xué)習(xí)到了新的知識(shí)，也從新復(fù)習(xí)了以前的知識(shí)，通過(guò)這個(gè)設(shè)計(jì)讓我從新掌握了機(jī)械制圖這門(mén)課程的內(nèi)容，在設(shè)計(jì)過(guò)程中也查閱了很多機(jī)械手冊(cè)，對(duì)于機(jī)械的零部件也了解到更多的知識(shí)，而且在做裝置的時(shí)候選擇用PRO-E作為輔助工具，也認(rèn)識(shí)到了機(jī)械裝置定位的重要性。
參 考 文 獻(xiàn)
[1]楊明忠，朱家誠(chéng) .機(jī)械設(shè)計(jì).武漢理工大學(xué)出版社 ， 2001.10
[2]卜炎. 機(jī)械傳動(dòng)裝置設(shè)計(jì)手冊(cè)（下）. 機(jī)械工業(yè)出版社 ， 1998
[3]成大先. 機(jī)械設(shè)計(jì)圖冊(cè)零部件的結(jié)構(gòu)與組合. 化學(xué)工業(yè)出版社， 1997
[4]李文哲 ，許綺川. 汽車(chē)拖拉機(jī)學(xué). 中國(guó)農(nóng)業(yè)出版社， 2006
[5]于永泗，齊民主. 機(jī)械工程材料. 大連理工大學(xué)， 2003
[6]譚建榮，張樹(shù)有，陸國(guó)棟，施岳定。 圖學(xué)基礎(chǔ)教程。 高等教育出版社，1999
[7]曾志新，呂明. 機(jī)械制造技術(shù)基礎(chǔ). 武漢理工大學(xué)出版社，2004
[8]余桂英，郭紀(jì)林. AutoCAD 2006中文版使用教程. 大連理工大學(xué)出版社，2006
[9]劉鴻文. 材料力學(xué). 高等教育出版社， 2004
[10]邵立新，夏素民，孫江宏.Pro/ENGINEER Wildfire 3.0 清華大學(xué)出版社，2007
致 謝
這次畢業(yè)設(shè)計(jì)可以圓滿的結(jié)束離不開(kāi)劉木華老師的親切關(guān)懷和耐心的指導(dǎo)，在整個(gè)畢業(yè)設(shè)計(jì)的過(guò)程中，劉老師對(duì)我的悉心指導(dǎo)和嚴(yán)格要求給我創(chuàng)造了良好的學(xué)習(xí)氛圍；他嚴(yán)謹(jǐn)?shù)目茖W(xué)態(tài)度，嚴(yán)謹(jǐn)?shù)闹螌W(xué)精神，精益求精的工作作風(fēng)，給我留下了深刻的印象，對(duì)我產(chǎn)生了巨大的影響，使我掌握了更多的理論知識(shí)。而且在分析問(wèn)題和解決問(wèn)題的能力上有了很大的提高。
在設(shè)計(jì)的過(guò)程中，我認(rèn)識(shí)到自己的不足，深刻的領(lǐng)會(huì)到掌握好專(zhuān)業(yè)知識(shí)的重要性。而且通過(guò)這次團(tuán)隊(duì)的設(shè)計(jì)，讓我感受到團(tuán)隊(duì)的力量。在此要感謝我的同組成員，他們?cè)诹私庾约旱臋C(jī)械的基礎(chǔ)上，幫我了解我的裝置，和我一起解決我遇到的問(wèn)題。
在專(zhuān)業(yè)知識(shí)方面我有欠缺。班級(jí)的其他同學(xué)也幫助我補(bǔ)齊我的知識(shí)，給于我耐心的幫助。在此要感謝我的同學(xué)。
當(dāng)然，作為一個(gè)本科生，盡管有導(dǎo)師的督促指導(dǎo)，以及一起工作的同學(xué)們的支持，但由于經(jīng)驗(yàn)的匱乏，難免有許多考慮不周全的地方，設(shè)計(jì)中難免有錯(cuò)誤和缺點(diǎn)，希望各位老師和同學(xué)能夠批評(píng)指正。
最后要感謝我的父母，他們給我上大學(xué)的機(jī)會(huì)，我還要感謝大學(xué)里的所有老師，他們教給我專(zhuān)業(yè)知識(shí)和做人的道理。為這次畢業(yè)設(shè)計(jì)打下了很好的基礎(chǔ)。
再次感謝所有幫助過(guò)我的人，在你們的幫助下才有我今天的成績(jī)。謝謝。
編號(hào)
無(wú)錫太湖學(xué)院
畢業(yè)設(shè)計(jì)（論文）
相關(guān)資料
題目： 工業(yè)窯爐的設(shè)計(jì)（輸送裝置）
信機(jī) 系 機(jī)械工程及自動(dòng)化 專(zhuān)業(yè)
學(xué) 號(hào)： 0923220
學(xué)生姓名： 李 歡
指導(dǎo)教師： 徐偉明（職稱(chēng)： 教 授 ）
（職稱(chēng)： ）
2013年5月25日
目 錄
一、畢業(yè)設(shè)計(jì)（論文）開(kāi)題報(bào)告
二、畢業(yè)設(shè)計(jì)（論文）外文資料翻譯及原文
三、學(xué)生“畢業(yè)論文（論文）計(jì)劃、進(jìn)度、檢查及落實(shí)表”
四、實(shí)習(xí)鑒定表
無(wú)錫太湖學(xué)院
畢業(yè)設(shè)計(jì)（論文）
開(kāi)題報(bào)告
題目： 工業(yè)窯爐的設(shè)計(jì)（輸送裝置）
信機(jī)系 機(jī)械工程及自動(dòng)化 專(zhuān)業(yè)
學(xué) 號(hào)： 0923220
學(xué)生姓名： 李 歡
指導(dǎo)教師： 徐偉明（職稱(chēng)： 教 授 ）
（職稱(chēng)： ）
2012年11月20日
課題來(lái)源
本課題來(lái)源于導(dǎo)師布置的任務(wù)導(dǎo)老師
科學(xué)依據(jù)（包括課題的科學(xué)意義；國(guó)內(nèi)外研究概況、水平和發(fā)展趨勢(shì)；應(yīng)用前景等）
輸送裝置的設(shè)計(jì)是機(jī)械工程及其自動(dòng)化專(zhuān)業(yè)所包含的一個(gè)較為基礎(chǔ)的內(nèi)容，選擇輸送裝置方向的畢業(yè)設(shè)計(jì)題目完全符合本專(zhuān)業(yè)的要求，從應(yīng)用性方面來(lái)說(shuō)，輸送裝置又是很多機(jī)器所必不可少的一個(gè)部分。有效保證輸送裝置的功率及穩(wěn)定性能夠達(dá)到設(shè)計(jì)的要求，具有很好的發(fā)展前途和應(yīng)用前景。
研究?jī)?nèi)容
1、 選擇電動(dòng)機(jī)，計(jì)算傳動(dòng)裝置的運(yùn)動(dòng)和動(dòng)力參數(shù)；
2、 擬定、分析傳動(dòng)裝置的運(yùn)動(dòng)和動(dòng)力參數(shù)；
3、 進(jìn)行傳動(dòng)件的設(shè)計(jì)計(jì)算，校核軸、軸承、聯(lián)軸器、鍵等；
4、 繪制減速器裝配圖及典型零件圖（圖紙數(shù)達(dá)到3張或以上）；
5、 完成設(shè)計(jì)說(shuō)明一份，分析明晰，計(jì)算正確，闡述清楚。適合的生產(chǎn)加工工 藝
擬采取的研究方法、技術(shù)路線、實(shí)驗(yàn)方案及可行性分析
首先確定整體設(shè)計(jì)方案，由公式的演算得到電動(dòng)機(jī)的動(dòng)力和運(yùn)動(dòng)分析，在以此推算相配的傳動(dòng)件，軸系零部件的尺寸規(guī)格。綜上計(jì)算可以得到相關(guān)尺寸，再根據(jù)力學(xué)性能對(duì)所得零部件尺寸進(jìn)行校驗(yàn)從而驗(yàn)證整體方案是否可行。
研究計(jì)劃及預(yù)期成果
研究計(jì)劃：
2012年11月 布置任務(wù)。
2013年1月 對(duì)課題研究方向進(jìn)行學(xué)習(xí)
2013年2月~3月 擬定方案，提出專(zhuān)機(jī)總體方案，供討論
2013年4月5日~10日 確定方案，專(zhuān)機(jī)總體布置
11日~20日 整機(jī)設(shè)計(jì)、部件設(shè)計(jì)
21日~30日 改進(jìn)并完成設(shè)計(jì)
2013年5月1日~10日 撰寫(xiě)設(shè)計(jì)說(shuō)明書(shū)
11日~15日 總結(jié)
預(yù)期成果：圖紙、設(shè)計(jì)說(shuō)明書(shū)
特色或創(chuàng)新之處
帶式輸送機(jī)本身便具有價(jià)格便宜，標(biāo)準(zhǔn)化程度高特點(diǎn)，使成本大幅降低。高速級(jí)齒輪常布置在遠(yuǎn)離扭矩輸入端的一邊，以減小因彎曲變形所引起的載荷沿齒寬分布不均現(xiàn)象。
已具備的條件和尚需解決的問(wèn)題
與指導(dǎo)老師的溝通中，對(duì)自己所做課題有了整體的認(rèn)識(shí)，清晰了思路。指導(dǎo)老師提供了論文指導(dǎo)，從而使自己明確了每一步的方向。因第一次繪制復(fù)雜的裝配圖，所以在繪圖方面還有待提高。
指導(dǎo)教師意見(jiàn)
同意作為本專(zhuān)業(yè)學(xué)生畢業(yè)設(shè)計(jì)課題，其難度和工作量均合適。
指導(dǎo)教師簽名：
年 月 日
教研室（學(xué)科組、研究所）意見(jiàn)
教研室主任簽名：
年 月 日
系意見(jiàn)
主管領(lǐng)導(dǎo)簽名：
年 月 日
英文原文
Esign of Speed Belt Conveyors
G. Lodewijks, The Netherlands.
This paper discusses aspects of high-speed belt conveyor design. The capacity of a belt conveyor is determined by the belt speed given a belt width and troughing angle. Belt speed selection however is limited by practical considerations, which are discussed in this paper. The belt speed also affects the performance of the conveyor belt, as for example its energy consumption and the stability of it's running behavior. A method is discussed to evaluate the energy consumption of conveyor belts by using the loss factor of transport. With variation of the belt speed the safety factor requirements vary, which will affect the required belt strength. A new method to account for the effect of the belt speed on the safety factor is presented. Finally, the impact of the belt speed on component selection and on the design of transfer stations is discussed.
Belt machine by conveyor belt continuous or intermittent motion to transport all kinds of different things ，Can transport all kinds of bulk materials, but also transport a variety of cardboard boxes, packaging bags, weight of single pieces of small goods, a wide range of uses . Belt conveyor belt material: rubber, silicone, PVC, PU and other materials, in addition to ordinary material conveying, but also to meet the transmission oil resistant, corrosion resistance, antistatic and other special requirements for material. Belt conveyor structure: groove belt machine, flat belt conveyor, climbing belt machine, turning machines and other forms belt, conveyor belt can also be created to enhance the tailgate, skirts and other accessories, can meet a variety of technological requirements.The belt conveyor drive: deceleration motor drive, electric drive roller.Belt conveyor mode: frequency control, stepless transmission.The belt rack material: carbon steel, stainless steel, aluminum profile.Scope of application: light industry, electronics, food, chemical, wood, etc..Belt machine equipment characteristics: belt conveyor is stable, the material and the conveyor belt there is no relative motion, to avoid damage to the carrier material. Low noise, suitable for quiet work environment requirements. Simple structure, easy maintenance. Low energy consumption, low use cost.
Conveyor is a common don't have flexible traction component continuous conveying machinery, also called continuous conveyor.It is a material handling equipment, it with handling ability strong, persistent, direction, flexible, and other advantages in industrial production in large being applied. Although many types of belt conveyor, but its working principle is basic similar, most are driving draught device and drive transmission container transport materials. Conveyor can undertake level, the tilt and vertical conveyor, also can make the space transport routes, transmission lines is usually fixed, is a modern production and logistics transport indispensable important mechanical equipment. It has transmission capacity is strong, long distance transportation etc.
With the development of industry, conveyor also obtained fast development, conveyor products have been also gradually improved. With the emergence of the power equipment of similar principle is applied, conveyor continuing into the 19th century, britons use basketwork, wire rope for traction belt conveyor. The principle of belt conveyor, when applied in the 17th century also recorded conveyor, in 1880 German company developed driven by steam belt conveyor. Then the British and German and launched inertial conveyor, if the conveyor belt, the application of the principle, creating a tilt of the belt conveyor, belt, traction with chains. All sorts of conveyor during this time arise conveyor, based on human, hydraulic power drive such. All the structures conveyor successively appeared. In 1887 americans produced the screw conveyor, make enterprise internal, between enterprise and inter-city transportation possible. The development history of belt conveyor, they very ancient instead of the original motive for conveyor provide driving force. Ancient people began to use water overturned and high TongChe conveyor, in turn after the water conservancy project's belt conveyor begin in power. Quick-tempered exalts
According to the mode of operation conveying machinery can be divided into: 1: belt conveyor 2: screw conveyor 3: dou pattern lift machine
The future of large scale, will toward belt use scope, energy consumption, low pollution less, material automatically grading, etc.
Past research has shown the economical feasibility of using narrower, faster running conveyor belts versus wider, slower running belts for long overland belt conveyor systems. See for example [I]-[5]. Today, conveyor belts running at speeds around 8 m/s are no exceptions. However, velocities over 10 m/s up to 20 m/s are technically (dynamically) feasible and may also be economically feasible. In this paper belt speeds between the 10 and 20 m/s are classified as high. Belt speeds below the 10 m/s are classified as low.
Using high belt speeds should never be a goal in itself. If using high belt speeds is not economically beneficial or if a safe and reliable operation is not ensured at a high belt speed then a lower belt speed should be selected.
Selection of the belt speed is part of the total design process. The optimum belt conveyor design is determined by static or steady state design methods. In these methods the belt is assumed to be a rigid, inelastic body. This enables quantification of the steady-state operation of the belt conveyor and determination of the size of conveyor components. The specification of the steady-state operation includes a quantification of the steady-state running belt tensions and power consumption for all material loading and relevant ambient conditions. It should be realized that finding the optimum design is not a one-time effort but an iterative process [6].
Design fine-tuning, determination of the optimum starting and stopping procedures, including determination of the required control algorithms, and determination of the settings and sizes of conveyor components such as drives, brakes and flywheels, are determined by dynamic design methods. In these design methods, also referred to as dynamic analyses, the belt is assumed to be a three-dimensional (visco-) elastic body. A three dimensional wave theory should be used to study time dependent transmission of large local force and displacement disturbances along the belt [7]. In this theory the belt is divided into a series of finite elements. The finite elements incorporate (visco-) elastic springs and masses. The constitutive characteristics of the finite elements must represent the rheological characteristics of the belt. Dynamic analysis produces the belt tension and power consumption during non-stationary operation, like starting and stopping, of the belt conveyor.
This paper discusses the design of high belt-speed conveyors, in particular the impact of using high belt speeds on the performance of the conveyor belt in terms of energy consumption and safety factor requirements. Using high belt speeds also requires high reliability of conveyor components such as idlers to achieve an acceptable component life. Another important aspect of high-speed belt conveyor design is the design of efficient feeding and discharge arrangements. These aspects will be discussed briefly.
Many methods of analyzing a belt’s physical behavior as a rheological spring have been studied and various techniques have been used. An appropriate model needs to address:
1. Elastic modulus of the belt longitudinal tensile member
2. Resistances to motion which are velocity dependent (i.e. idlers)
3. Viscoelastic losses due to rubber-idler indentation
4. Apparent belt modulus changes due to belt sag between idlers
Since the mathematics necessary to solve these dynamic problems are very complex, it is not the goal of this presentation to detail the theoretical basis of dynamic analysis. Rather, the purpose is to stress that as belt lengths increase and as horizontal curves and distributed power becomes more common, the importance of dynamic analysis taking belt elasticity into account is vital to properly develop control algorithms during both stopping and starting.
Using the 8.5 km conveyor in Figure 23 as an example, two simulations of starting were performed to compare control algorithms. With a 2x1000 kW drive installed at the head end, a 2x1000 kW drive at a midpoint carry side location and a 1x1000kW drive at the tail, extreme care must be taken to insure proper coordination of all drives is maintained.
Figure 27 illustrates a 90 second start with very poor coordination and severe oscillations in torque with corresponding oscillations in velocity and belt tensions. The T1/T2 slip ratio indicates drive slip could occur. Figure 28 shows the corresponding charts from a relatively good 180 second start coordinated to safely and
smoothly accelerate the conveyor.
Figure 27-120 Sec Poor Start
BELTSPEED
BELT SPEED SELECTION
The lowest overall belt conveyor cost occur in the range of belt widths of 0.6 to 1.0 m [2]. The required conveying capacity can be reached by selection of a belt width in this range and selecting whatever belt speed is required to achieve the required flow rate. Figure 1 shows an example of combinations of belt speed and belt width to achieve Specific conveyor capacities. In this example it is assumed that the bulk density is 850 kg/m3 (coal) and that the trough angle and the surcharge angle are 35' and 20' respectively.
Figure 1: Belt width versus belt speed for different capacities.
Belt speed selection is however limited by practical considerations. A first aspect is the troughability of the belt. In Figure 1 there is no relation with the required belt strength (rating), which partly depends on the conveyor length and elevation. The combination of belt width and strength must be chosen such that good troughability of the belt is ensured. If the troughability is not sufficient then the belt will not track properly. This will result in unstable running behavior of the belt, in particular at high belt speeds, which is not acceptable. Normally, belt manufacturers expect a sufficiently straight run if approximately 40% of the belt width when running empty, makes contact with the carrying idlers. Approximately 10% should make tangential contact with the center idler roll.
A second aspect is the speed of the air relative to the speed of the bulk solid material on the belt (relative airspeed). If the relative airspeed exceeds certain limits then dust will develop. This is in particular a potential problem in mine shafts where a downward airflow is maintained for ventilation purposes. The limit in relative airspeed depends on ambient conditions and bulk material characteristics.
A third aspect is the noise generated by the belt conveyor system. Noise levels generally increase with increasing belt speed. In residential areas noise levels are restricted to for example 65 dB. Although noise levels are greatly affected by the design of the conveyor support structure and conveyor covers, this may be a limiting factor in selecting the belt speed.
BELT SPEED VARIATION
The energy consumption of belt conveyor systems varies with variation of the belt speed, as will be shown in Section 3. The belt velocity can be adjusted with bulk material flow supplied at the loading point to save energy. If the belt is operating at full tonnage then it should run at the high (design) belt speed. The belt speed can be adjusted (decreased) to the actual material (volume) flow supplied at the loading point. This will maintain a constant filling of the belt trough and a constant bulk material load on the belt. A constant filling of the belt trough yields an optimum loading-ratio, and lower energy consumption per unit of conveyed material may be expected. The reduction in energy consumption will be at least 10% for systems where the belt speed is varied compared to systems where the belt speed is kept constant [8].
Varying the belt speed with supplied bulk material flow has the following advantages:
Less belt wear at the loading areas
Lower noise emission
Improved operating behavior as a result of better belt alignment and the avoidance of belt lifting in concave curve by reducing belt tensions
Drawbacks include:
Investment cost for controllability of the drive and brake systems
Variation of discharge parabola with belt speed variation
Control system required for controlling individual conveyors in a conveyor system
Constant high belt pre-tension
Constant high bulk material load on the idler rolls
An analysis should be made of the expected energy savings to determine whether it is worth the effort of installing a more expensive, more complex conveyor system.
ENERGY CONSUMPTION
Clients may request a specification of the energy consumption of a conveyor system, for example quantified in terms of maximum kW-hr/ton/km, to transport the bulk solid material at the design specifications over the projected route. For long overland systems, the energy consumption is mainly determined by the work done to overcome the indentation rolling resistance [9]. This is the resistance that the belt experiences due to the visco-elastic (time delayed) response of the rubber belt cover to the indentation of the idler roll. For in-plant belt conveyors, work done to overcome side resistances that occur mainly in the loading area also affects the energy consumption. Side resistances include the resistance due to friction on the side walls of the chute and resistance that occurs due to acceleration of the material at the loading point.
The required drive power of a belt conveyor is determined by the sum of the total frictional resistances and the total material lift. The frictional resistances include hysteresis losses, which can be considered as viscous (velocity dependent) friction components. It does not suffice to look just at the maximum required drive power to evaluate whether or not the energy consumption of a conveyor system is reasonable. The best method to compare the energy consumption of different transport systems is to compare their transport efficiencies.
TRANSPORT EFFICIENCY
There are a number of methods to compare transport efficiencies. The first and most widely applied method is to compare equivalent friction factors such as the DIN f factor. An advantage of using an equivalent friction factor is that it can also be determined for an empty belt. A drawback of using an equivalent friction factor is that it is not a 'pure' efficiency number. It takes into account the mass of the belt, reduced mass of the rollers and the mass of the transported material. In a pure efficiency number, only the mass of the transported material is taken into account.
The second method is to compare transportation cost, either in kW-hr/ton/km or in $/ton/km. The advantage of using the transportation cost is that this number is widely used for management purposes. The disadvantage of using the transportation cost is that it does not directly reflect the efficiency of a system.
The third and most "pure" method is to compare the loss factor of transport [10]. The loss factor of transport is the ratio between the drive power required to overcome frictional losses (neglecting drive efficiency and power loss/gain required to raise/lower the bulk material) and the transport work. The transport work is defined as the multiplication of the total transported quantity of bulk material and the average transport velocity. The advantage of using loss factors of transport is that they can be compared to loss factors of transport of other means of transport, like trucks and trains. The disadvantage is that the loss factor of transport depends on the transported quantity of material, which implies that it can not be determined for an empty belt conveyor.
The following are loss factors of transport for a number of transport systems to illustrate the concept:
Continuous transport:
Slurry transport around 0.01
Belt conveyors between 0.01 and 0.1
Vibratory feeders between 0.1 and 1
Pneumatic conveyors around 1 0
Discontinuous transport:
Ship between 0.001 and 0.01
Train around 0.01
Truck between 0.05 and 0.1
INDENTATION ROLLING RESISTANCE
For long overland systems, the energy consumption is mainly determined by the work done to overcome the indentation rolling resistance. Idler rolls are made of a relatively hard material like steel or aluminum whereas conveyor belt covers are made of much softer materials like rubber or PVC. The rolls therefore indent the belt's bottom-cover when the belt moves over the idler rolls, due to the weight of the belt and bulk material on the belt. The recovery of the compressed parts of the belt's bottom cover will take some time due to its visco-elastic (time dependent) properties. The time delay in the recovery of the belt's bottom cover results in an asymmetrical stress distribution between the belt and the rolls, see Figure 2. This yields a resultant resistance force called the indentation rolling resistance force. The magnitude of this force depends on the visco-elastic properties of the cover material, the radius of the idler roll, the vertical force due to the weight of the belt and the bulk solid material, and the radius of curvature of the belt in curves in the vertical plane.
Figure 2: Asymmetric stress distribution between belt and roll [7].
It is important to know how the indentation rolling resistance depends on the belt velocity to enable selection of a proper belt velocity, [11].
Figure 3: Loss factor (tanb) of typical cove
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