鋼筋切斷機設(shè)計帶CAD圖

鋼筋切斷機設(shè)計帶CAD圖,鋼筋,切斷,設(shè)計,CAD 1 引言11 概述鋼筋切斷機是鋼筋加工必不可少的設(shè)備之一，它主要用語房屋建筑、橋梁、隧道、電站、大型水利等工程中對鋼筋的定長切斷。鋼筋切斷機與其他切斷設(shè)備相比，具有重量輕、耗能少、工作可靠、效率高等特點，因此近年來逐步被機械加工和小型軋鋼廠等廣泛采用，在國民經(jīng)濟建設(shè)的各個領(lǐng)域發(fā)揮了重要的作用。國內(nèi)外切斷機的對比：由于切斷機技術(shù)含量低、易仿造、利潤不高等原因，所以廠家?guī)资陙砘揪S持現(xiàn)狀，發(fā)展不快，與國外同行相比具體有以下幾方面差距。1)國外切斷機偏心軸的偏心距較大，如日本立式切斷機偏心距24mm，而國內(nèi)一般為17mm看似省料、齒輪結(jié)構(gòu)偏小些，但給用戶帶來麻煩，不易管理因為在由切大料到切小料時，不是換刀墊就是換刀片，有時還需要轉(zhuǎn)換角度。2)國外切斷機的機架都是鋼板焊接結(jié)構(gòu)，零部件加工精度、粗糙度尤其熱處理工藝過硬，使切斷機在承受過載荷、疲勞失效、磨損等方面都超過國產(chǎn)機器3)國內(nèi)切斷機刀片設(shè)計不合理，單螺栓固定，刀片厚度夠薄，40型和50型刀片厚度均為17mm；而國外都是雙螺栓固定，2527mm厚，因此國外刀片在受力及壽命等綜合性能方面都較國內(nèi)優(yōu)良。4)國內(nèi)切斷機每分鐘切斷次數(shù)少國內(nèi)一般為2831次，國外要高出1520次，最高高出30次，工作效率較高。5)國外機型一般采用半開式結(jié)構(gòu)，齒輪、軸承用油脂潤滑，曲軸軸徑、連桿瓦、沖切刀座、轉(zhuǎn)體處用手工加稀油潤滑國內(nèi)機型結(jié)構(gòu)有全開、全閉、半開半閉3種，潤滑方式有集中稀油潤滑和飛濺潤滑2種。6)國內(nèi)切斷機外觀質(zhì)量、整機性能不盡人意；國外廠家一般都是規(guī)模生產(chǎn)，在技術(shù)設(shè)備上舍得投入，自動化生產(chǎn)水平較高，形成一套完整的質(zhì)量保證加工體系。尤其對外觀質(zhì)量更是精益求精，外罩一次性沖壓成型，油漆經(jīng)烤漆噴涂處理，色澤搭配科學(xué)合理，外觀看不到哪兒有焊縫、毛刺、尖角，整機光潔美觀。而國內(nèi)一些一些廠家雖然生產(chǎn)歷史較長，但沒有一家形成規(guī)模，加之設(shè)備老化，加工過程拼體力、經(jīng)驗，生產(chǎn)工藝幾十年一貫制，所以外觀質(zhì)量粗糙、觀感較差。全球經(jīng)濟建設(shè)的快速發(fā)展為建筑行業(yè)，特別是為建筑機械的發(fā)展提供了一個廣闊的發(fā)展空間，為廣大生產(chǎn)企業(yè)提供一個展示自己的舞臺。面對競爭日益激烈的我國建筑機械市場，加強企業(yè)的經(jīng)營管理，加大科技投入，重視新技術(shù)、新產(chǎn)品的研究開發(fā)，提高產(chǎn)品質(zhì)量和產(chǎn)品售后服務(wù)水平，積極、主動走向市場，使企業(yè)的產(chǎn)品不斷地滿足用戶的需求，盡快縮短與國外先進企業(yè)的差距，無疑是我國鋼筋切斷機生產(chǎn)企業(yè)生存與發(fā)展的必由之路。12 題目的選取本次畢業(yè)設(shè)計的任務(wù)是臥式鋼筋切斷機的設(shè)計。要求切斷鋼筋的最大直徑14mm，切斷速度為15次/分。在設(shè)計中通過計算和考慮實際情況選則合適的結(jié)構(gòu)及參數(shù)，從而達到設(shè)計要求，同時盡可能的降低成本，這也是一個綜合運用所學(xué)專業(yè)知識的過程。畢業(yè)設(shè)計是對四年大學(xué)所學(xué)知識的一個總結(jié)，也是走上工作崗位前的一次模擬訓(xùn)練。13 鋼筋切斷機的工作原理工作原理：采用電動機經(jīng)一級三角帶傳動和二級齒輪傳動減速后,帶動曲軸旋轉(zhuǎn),曲軸推動連桿使滑塊和動刀片在機座的滑道中作往復(fù)直線運動,使活動刀片和固定刀片相錯而切斷鋼筋。2 電機選擇 傳動方案簡述：選擇三級減速，先是一級帶減速，再兩級齒輪減速。首先采用一級帶傳動，因為它具有緩沖、吸振、運行平穩(wěn)、噪聲小、合過載保護等優(yōu)點，并安裝張緊輪。然后采用兩級齒輪減速，因為齒輪傳動可用來傳遞空間任意兩軸間的運動和動力，并具有功率范圍大，傳動效率高，傳動比準(zhǔn)確，使用壽命長，工作安全可靠等特點。動力由電動機輸出,通過減速系統(tǒng)傳動,把動力輸入到執(zhí)行機構(gòu)。由于傳動系統(tǒng)作 的是回轉(zhuǎn)運動,而鋼筋切斷機的執(zhí)行機構(gòu)需要的直線往復(fù)運動,為了實現(xiàn)這種轉(zhuǎn)換,可以采用曲柄滑塊機構(gòu),盤行凸輪移動滾子從動件機構(gòu),齒輪齒條機構(gòu)。考慮現(xiàn)實條件我決定采用曲柄滑塊機構(gòu)作為本機械的執(zhí)行機構(gòu)。2.1切斷鋼筋需用力計算為了保證鋼筋的剪斷，剪應(yīng)力應(yīng)超過材料的許應(yīng)剪應(yīng)力。即切斷鋼筋的條件為： 查資料可知鋼筋的許用剪應(yīng)力為：MPa,取最大值142MPa。由于本切斷機切斷的最大剛筋粗度為：mm。則本機器的最小切斷力為： 取切斷機的Q=22000N。2.2 功率計算由圖可知，刀的速度小于曲軸處的線速度。則切斷處的功率P：W 查表可知在傳動過程中，帶傳動的效率為= 0.940.97； 二級齒輪減速器的效率為= 0.960.99； 滾動軸承的傳動效率為= 0.940.98； 連桿傳動的效率為= 0.810.88；滑動軸承的效率為由以上可知總的傳動效率為:= 0.940.960.980.81=0.72由此可知所選電機功率最小應(yīng)為 kw查手冊并根據(jù)電機的工作環(huán)境和性質(zhì)選取電機為：Y系列封閉式三相異步電動機，代號為Y112M-6，輸出功率為2.2kw，輸出速度為960 r/min。3. 傳動結(jié)構(gòu)設(shè)計3.1 基本傳動數(shù)據(jù)計算3.1.1 分配傳動比電動機型號為Y，滿載轉(zhuǎn)速為960 r/min。a) 總傳動比 b) 分配傳動裝置的傳動比 上式中i0、i1分別為帶傳動與減速器（兩級齒輪減速）的傳動比，為使V帶傳動的外廓尺寸不致過大，同時使減速器的傳動比圓整以便更方便的獲得圓整地齒數(shù)。初步取i0 =2，則減速器的傳動比為 c) 分配減速器的各級傳動比按展開式布置，查閱有關(guān)標(biāo)準(zhǔn)，取 i11=6.4，則i22=5。（注以下有i1代替i11，i2代替i22）3.1.2 計算機構(gòu)各軸的運動及動力參數(shù)a) 各軸的轉(zhuǎn)速 軸 軸 軸 b) 各軸的輸入功率 軸 軸 軸c) 各軸的輸入轉(zhuǎn)矩 電動機輸出轉(zhuǎn)矩 軸 軸 軸 3.2 帶傳動設(shè)計3.2.1 由設(shè)計可知：V帶傳動的功率為2.2kw，小帶輪的轉(zhuǎn)速為960r/min，大帶輪的轉(zhuǎn)速為480r/min。查表可知 工況系數(shù)取 KA=1.5 ，Pc=1.52.2=3.3kw。根據(jù)以上數(shù)值及小帶輪的轉(zhuǎn)速查相應(yīng)得圖表選取A型V帶。3.2.2 帶輪基準(zhǔn)直徑：查閱相關(guān)手冊選取小帶輪基準(zhǔn)直徑為d1=100mm，則大帶輪基準(zhǔn)直徑為d2=2100=200mm3.2.3 帶速的確定：3.2.4 中心矩、帶長及包角的確定。由式 0.7(d1+d2)a02(d1+d2) 可知： 0.7(100+200)a02(100+200) 得 210a0600 初步確定中心矩為 a0=400 根據(jù)相關(guān)公式初步計算帶的基準(zhǔn)長度： 查表選取帶的長度為1250mm計算實際中心矩： 取386mm驗算小帶輪包角： 3.2.5 確定帶的根數(shù)： 查表知 p1=0.97 p1=0.11 ka=0.965 kl=0.93 則 取Z=43.2.6 張緊力 查表 q=0.10kg/m 3.2.7 作用在軸上的載荷： 3.2.8 帶輪結(jié)構(gòu)與尺寸見零件圖圖1 帶輪的結(jié)構(gòu)與尺寸圖3.3 齒輪傳動設(shè)計3.3.1 第一級齒輪傳動設(shè)計a) 選材料、確定初步參數(shù)1) 選材料 小齒輪：40Cr鋼調(diào)制，平均取齒面硬度為260HBS 大齒輪：45鋼調(diào)制，平均取齒面硬度為260HBS2) 初選齒數(shù) 取小齒輪的齒數(shù)為20，則大齒輪的齒數(shù)為206.4=1283) 齒數(shù)比即為傳動比 4) 選擇尺寬系數(shù)d和傳動精度等級情況，參照相關(guān)手冊并根據(jù)以前學(xué)過的知識選取 d=0.6初估小齒輪直徑d1=60mm，則小齒輪的尺寬為b=d d1=0.660=36mm5) 齒輪圓周速度為： 參照手冊選精度等級為9級。6) 計算小齒輪轉(zhuǎn)矩T17) 確定重合度系數(shù)Z、Y：由公式可知重合度為則由手冊中相應(yīng)公式可知：8) 確定載荷系數(shù) KH 、KF確定使用系數(shù) KA：查閱手冊選取使用系數(shù)為KA=1.85確定動載系數(shù)Kv：查閱手冊選取動載系數(shù)Kv=1.10確定齒間載荷分布系數(shù)KHa、KFa：則 載荷系數(shù)KH、KF 的確定，由公式可知b) 齒面疲勞強度計算1) 確定許用應(yīng)力H 總工作時間th，假設(shè)該切斷機的壽命為10年，每年工作300天，每天工作8個小時，則： 應(yīng)力循環(huán)次數(shù) N1、N2 壽命系數(shù) Zn1、Zn2 ，查閱相關(guān)手冊選取Zn1=1.0、Zn2=1.15 接觸疲勞極限取：hlim1=720MPa、hlim2=580MPa 安全系數(shù)取：Sh=1.0 許用應(yīng)力 h1、h2 2) 彈性系數(shù)ZE 查閱機械設(shè)計手冊可選取3) 節(jié)點區(qū)域系數(shù)ZH查閱機械設(shè)計手冊可選取ZH=2.54) 求所需小齒輪直徑d1 與初估大小基本相符。5) 確定中心距，模數(shù)等幾何參數(shù) 中心距a： 圓整中心矩取222mm 模數(shù)m：由中心矩a及初選齒數(shù)Z1 、Z2得： 分度圓直徑d1,d2 確定尺寬：取大齒輪尺寬為 b1=600.6=36mm 小齒輪尺寬取 b2=40mmc) 齒根抗彎疲勞強度驗算1) 求許用彎曲應(yīng)力 F 應(yīng)力循環(huán)次數(shù)NF1、NF2 壽命系數(shù)Yn1、Yn2 ，查閱相關(guān)手冊選取Yn1=1、Yn2=1 極限應(yīng)力取：Flim1=290MPa、Flim2=220MPa 尺寸系數(shù)Yx：查閱機械設(shè)計手冊選，取Yx=1.5 安全系數(shù)SF：參照表9-13，取SF=1.5 需用應(yīng)力F1 、F2 由式（9-20），許用彎曲應(yīng)力 2) 齒形系數(shù)YFa1、YFa2 由圖9-19，取 YFa1=2.56 YFa2=2.153) 應(yīng)力修正系數(shù)Ysa1、Ysa2 由圖9-20，取 Ysa1=1.62 Ysa2=1.824) 校核齒根抗彎疲勞強度 由式（9-17），齒根彎曲應(yīng)力 3.3.2 第二級齒輪傳動設(shè)計：a) 選材料、確定初步參數(shù)1) 選材料 小齒輪：40Cr鋼調(diào)制，平均取齒面硬度為260HBS 大齒輪：45鋼調(diào)制，平均取齒面硬度為260HBS2) 初選齒數(shù) 取小齒輪的齒數(shù)為28，則大齒輪的齒數(shù)為285=1403) 齒數(shù)比即為傳動比 4) 選擇尺寬系數(shù)d和傳動精度等級情況，參照相關(guān)手冊并根據(jù)以前學(xué)過的知識選取 d=2/3初估小齒輪直徑d1=84mm，則小齒輪的尺寬為b=d d1=2/384=56mm齒輪圓周速度為： 參照手冊選精度等級為9級。5) 計算小齒輪轉(zhuǎn)矩T16) 確定重合度系數(shù)Z、Y：由公式可知重合度為則由手冊中相應(yīng)公式可知：7) 確定載荷系數(shù) KH 、KF確定使用系數(shù) KA：查閱手冊選取使用系數(shù)為KA=1.85確定動載系數(shù)Kv：查閱手冊選取動載系數(shù)Kv=1.0確定齒間載荷分布系數(shù)KHa、KFa：則 載荷系數(shù)KH、KF 的確定，由公式可知c) 齒面疲勞強度計算1) 確定許用應(yīng)力H 總工作時間th，假設(shè)該彎曲機的壽命為10年，每年工作300天，每天工作8個小時，則： 應(yīng)力循環(huán)次數(shù) N1、N2壽命系數(shù) Zn1、Zn2 ，查閱相關(guān)手冊選取Zn1=1.33、Zn2=1.48接觸疲勞極限?。篽lim1=760MPa、hlim2=760MPa安全系數(shù)?。篠h=1許用應(yīng)力 h1、h2 2) 彈性系數(shù)ZE 查閱機械設(shè)計手冊可選取3) 節(jié)點區(qū)域系數(shù)ZH查閱機械設(shè)計手冊可選取ZH=2.54) 求所需小齒輪直徑d1 與初估大小基本相符。5) 確定中心距，模數(shù)等幾何參數(shù) 中心距a： 圓整中心矩取252mm 模數(shù)m：由中心矩a及初選齒數(shù)Z1 、Z2得： 分度圓直徑d1,d2 確定尺寬：取大齒輪尺寬為 b1=842/3=56mm 小齒輪尺寬取 b2=60mmc) 齒根抗彎疲勞強度驗算1) 求許用彎曲應(yīng)力 F 應(yīng)力循環(huán)次數(shù)NF1、NF2 壽命系數(shù)Yn1、Yn2 ，查閱相關(guān)手冊選取Yn1=1、Yn2=1 極限應(yīng)力?。篎lim1=290MPa、Flim2=230MPa 尺寸系數(shù)Yx：查閱機械設(shè)計手冊選，取Yx=1.5 安全系數(shù)SF：參照表9-13，取SF=1.5 需用應(yīng)力F1 、F2 由式（9-20），許用彎曲應(yīng)力 2) 齒形系數(shù)YFa1、YFa2 由圖9-19，取 YFa1=2.56 YFa2=2.153) 應(yīng)力修正系數(shù)Ysa1、Ysa2 由圖9-20，取 Ysa1=1.62 Ysa2=1.824) 校核齒根抗彎疲勞強度 由式（9-17），齒根彎曲應(yīng)力 3.4 軸的校核3.4.1 一軸的校核 軸直徑的設(shè)計式 軸的剛度計算a) 按當(dāng)量彎矩法校核1) 設(shè)計軸系結(jié)構(gòu)，確定軸的受力簡圖、彎矩圖、合成彎矩圖、轉(zhuǎn)矩圖和當(dāng)量彎矩圖。圖2 軸的受力轉(zhuǎn)矩彎矩圖2) 求作用在軸上的力如表1，作圖如圖2-c表1 作用在軸上的力垂直面（Fv）水平面（Fh）軸承1F2=12NF4=891N齒輪 2=N軸承3F1=476NF3=1570N帶輪41056N3） 求作用在軸上的彎矩如表2，作出彎矩圖如圖2-d、2-e表2 作用在軸上的彎矩垂直面（Mv）水平面（Mh）截面N.mm合成彎矩截面合成彎矩4）作出轉(zhuǎn)彎矩圖如圖2-f5）作出當(dāng)量彎矩圖如圖2-g，并確定可能的危險截面、如圖2-a。并算出危險截面的彎矩如表3。表3截面的彎矩截面截面6）確定許用應(yīng)力已知軸材料為45鋼調(diào)質(zhì)，查表得=650MPa。用插入法查表得=102.5MPa，=60MPa。7）校核軸徑如表4表4 驗算軸徑截面截面結(jié)論：按當(dāng)量彎矩法校核，軸的強度足夠。b) 軸的剛度計算所以軸的剛度足夠3.4.2 三軸的校核 軸直徑的設(shè)計式 軸的剛度計算a) 按當(dāng)量彎矩法校核設(shè)計軸系結(jié)構(gòu)，確定軸的受力簡圖、彎矩圖、合成彎矩圖、轉(zhuǎn)矩圖和當(dāng)量彎矩圖。1） 軸的受力簡圖如圖3-a圖3 軸的受力彎矩轉(zhuǎn)矩圖2） 求作用在軸上的力如表5，并作圖如圖3-c表5 作用在軸上的力垂直面（Fv）水平面（Fh）軸承1F3=1627NF1=8362N齒輪 =2381N軸承2F4=754NF3=12619N曲軸21848N3）計算出彎矩如表6，并作圖如圖3-d、e表6 軸上的彎矩垂直面（Mv）水平面（Mh）截面N.mm合成彎矩截面合成彎矩4）作出轉(zhuǎn)彎矩圖如圖3-f5）作出當(dāng)量彎矩圖如圖3-g，并確定可能的危險截面、和的彎矩如表7表7危險截面的彎矩截面截面6）確定許用應(yīng)力已知軸材料為45鋼調(diào)質(zhì)，查表得=650MPa。用插入法查表得=102.5MPa，=60MPa7）校核軸徑如表8表8 校核軸徑截面截面結(jié)論：按當(dāng)量彎矩法校核，軸的強度足夠。b) 軸的剛度計算所以軸的剛度足夠3.5 鍵的校核3.5.1. 平鍵的強度校核. a) 鍵的選擇 鍵的類型應(yīng)根據(jù)鍵聯(lián)接的結(jié)構(gòu)使用要求和工作狀況來選擇。選擇時應(yīng)考慮傳遞轉(zhuǎn)拒的大小，聯(lián)接的對中性要求，是否要求軸向固定，聯(lián)接于軸上的零件是否需要沿軸滑動及滑動距離長短，以及鍵在軸上的位置等。鍵的主要尺寸為其橫截面尺寸(鍵寬b 鍵高h)與長度L。鍵的橫截面尺寸bh 依軸的直徑d由標(biāo)準(zhǔn)中選取。鍵的長度L一般可按輪轂的長度選定，即鍵長略短于輪轂長度，并應(yīng)符合標(biāo)準(zhǔn)規(guī)定的長度系列。故根據(jù)以上所提出的以及該機工作時的要求，故選用A型普通平鍵。由設(shè)計手冊查得：鍵寬 b=16mm 鍵高 h=10mm 鍵長 L=30mmb) 驗算擠壓強度.平鍵聯(lián)接的失效形式有：對普通平鍵聯(lián)接而言，其失效形式為鍵，軸，輪轂三者中較弱的工作表面被壓潰。工程設(shè)計中，假定壓力沿鍵長和鍵高均勻分布，可按平均擠壓應(yīng)力進行擠壓強度或耐磨性的條件計算，即：靜聯(lián)接 式中 傳遞的轉(zhuǎn)矩 軸的直徑 鍵與輪轂的接觸高度(mm)，一般取 鍵的接觸長度(mm).圓頭平鍵 許用擠壓應(yīng)力) 鍵的工作長度 擠壓面高度 轉(zhuǎn)矩 許用擠壓應(yīng)力，查表， 則 擠壓應(yīng)力 所以 此鍵是安全的。附：鍵的材料：因為壓潰和磨損是鍵聯(lián)接的主要失效形式，所以鍵的材料要求有足夠的硬度。國家標(biāo)準(zhǔn)規(guī)定，鍵用抗拉強度不低于的鋼制造，如 45鋼 Q275 等。3.6 軸承的校核 滾動軸承是又專業(yè)工廠生產(chǎn)的標(biāo)準(zhǔn)件。滾動軸承的類型、尺寸和公差等級均已制訂有國家標(biāo)準(zhǔn)，在機械設(shè)計中只需根據(jù)工作條件選擇合適的軸承類型、尺寸和公差等級等，并進行軸承的組合結(jié)構(gòu)設(shè)計。3.6.1 初選軸承型號 試選10000K軸承，查GB281-1994，查得10000K軸承的性能參數(shù)為： C=14617N Co=162850N (脂潤滑)3.6.2壽命計算 a) 計算軸承內(nèi)部軸向力. 查表得10000K軸承的內(nèi)部軸向力 則： b) 計算外加軸向載荷 c) 計算軸承的軸向載荷 因為 故 軸承1 軸承2 d) 當(dāng)量動載荷計算 由式 查表得： 的界限值 查表知 故 故 則： 式中. (輕度沖擊的運轉(zhuǎn))由于 ，且軸承1、2采用型號、尺寸相同的軸承，谷只對軸承2進行壽命計算。e) 計算軸承壽命 f) 極限轉(zhuǎn)速計算 由式 查得：載荷系數(shù) 載荷分布系數(shù) 故 計算結(jié)果表明，選用的10000K型圓柱孔調(diào)心軸承能滿足要求。4 鋼筋切斷機的摩擦、磨損和潤滑摩擦是不可避免的自然現(xiàn)象，摩擦得結(jié)果造成機器的能量損耗、效率降低、溫度升高、出現(xiàn)噪聲、性能下降的問題。摩擦必然會造成磨損，在實際應(yīng)用中有許多零件都 因磨損過渡而報廢。潤滑則是改善摩擦、減緩磨損的有效方法。切斷機中的摩擦主要是軸承的摩擦，而磨損包括滑動摩擦和滾動摩擦。軸承就是滾動摩擦，其摩擦力較小損耗也較小。摩擦得結(jié)果勢必會造成磨損，而影響磨損的因素也有很多，主要有載荷大小、材料匹配、潤滑狀況、工作溫度等。為減少磨損需要從這些方面入手，采取各種有效方法，減少磨損。減少磨損的主要方法有：1.潤滑。2.注意選擇材料，按照基本磨損形式正確選擇材料是提高機械和零件耐磨性的關(guān)鍵之一。3.提高加工精度和表面質(zhì)量也可以減少磨損。4.合理的結(jié)構(gòu)設(shè)計，正確合理的結(jié)構(gòu)設(shè)計是減少磨損和提高耐磨性的有效途徑。5.正確使用和維護。 結(jié)束語本次設(shè)計的是一種結(jié)構(gòu)比較簡明實用的鋼筋切斷裝置，該裝置的特點是價格低廉，節(jié)省空間，維修方便。該切斷機是采用電動機經(jīng)一級帶傳動和二級齒輪傳動減速后,帶動曲軸旋轉(zhuǎn),曲軸推動連桿使滑塊和動刀片在機座的滑道中作往復(fù)直線運動,使活動刀片和固定刀片相錯而切斷鋼筋。并用型鋼焊接了鋼架，使其結(jié)構(gòu)盡可能的簡單。在設(shè)計中，我盡可能的采用通用部件，從而使設(shè)計周期縮短，成本降低。設(shè)計過程中，我主要考慮了機器的性能以及經(jīng)濟性，在保證其完成工作要求的前提下，盡可能的提高其性價比。這是我第一次搞這樣的綜合性的設(shè)計，所以設(shè)計中難免會出現(xiàn)一些漏洞或不足之處，如一些結(jié)構(gòu)的設(shè)計，標(biāo)準(zhǔn)件的選用或一些經(jīng)濟性上的構(gòu)思可能有欠妥當(dāng)，造成一些不必要的浪費，敬請各位老師給予批評和指正。通過這次設(shè)計，使我的綜合考慮問題的能力得到了提高，而且通過綜合的運用機械知識，使自己的專業(yè)水平得到了很大的進步。夠已經(jīng)能初步的將理論知識運用到實踐中去，為以后的工作打下良好的基礎(chǔ)。致謝參 考 文 獻 1 蘇翼林主編.材料力學(xué)（第3版）.天津：天津大學(xué)出版社，20012 孫桓，陳作模主編.機械原理（第6版）.北京：高等教育出版社，20013 李繼慶，陳作模主編.機械設(shè)計基礎(chǔ).北京：高等教育出版社，19994 梁崇高等著.平面連桿機構(gòu)的計算設(shè)計.北京：高等教育出版社，19935 劉政昆編著.間歇運動機構(gòu).大連：大連理工大學(xué)出版社，19916 伏爾默J等著.連桿機構(gòu).石則昌等譯.北京：機械工業(yè)出版社，19907 田野編寫.我國鋼筋調(diào)直切斷機的現(xiàn)狀及發(fā)展.建筑機械化，2005年第1期23頁8 王慰椿.機械基礎(chǔ)與建筑機械.南京：東南大學(xué)出版社，19909 高蕊.鋼筋切斷機切斷過程分析及最大沖切力的計算.建筑機械，1995第2期24-25頁10 何德譽.曲柄壓力機.北京：清華大學(xué)出版社，198711 車仁煒，陸念力 王樹春.一種新型鋼筋切斷機的設(shè)計研究.機械傳動，2004年第2期48-49頁12 高蕊.鋼筋切斷機刀片合理側(cè)隙的保證方法.建筑機械化，1997年第4期37-38頁 13 王平，張強，許世輝.鋼筋調(diào)直切斷機的頂?shù)杜c連切J.建筑機械,1997年第5期47-48頁14 宜亞麗.鋼筋矯直切斷機剪切機構(gòu)研究分析.機械，2004年第10期14-16頁15 孟進禮，衛(wèi)青珍.對鋼筋切斷機發(fā)展的幾點看法.建筑機械化，2000年第2期14-15頁16 Trans.ASME.77(2),1955International Journal of Computer Applications (0975 8887) Volume 57 No.16, November 2012 15 Design and Implementation of PLC based Computerized Monitoring in Dip Coating System G.Madhan G.R.Kandhasamy S.Muruganand Department of Electronics and Instrumentation Department of Electronics and Instrumentation Department of Electronics and Instrumentation Bharathiar University Bharathiar University Bharathiar University Coimbatore Coimbatore Coimbatore India India India ABSTRACT The present study is about the design and implementation of dip coating system based on Programmable Logic Controller (PLC) technology. The PLC correlates the operation parameters control required by the user and monitors the system during normal operation and under dipping conditions. Tests of dip coating system driven by DC motor driver and controlled by PLC prove a higher accuracy in regulation as compared to manual human works. The implementation of the hardware and software for control system and results obtained from tests on dip coating performance is provided. Thus, PLC is proved as a versatile and wide effective tool in industrial control of electric drives. General Terms Programmable logic controller (PLC), Printed circuit Board (PCB), Toggle switch. Keywords Dip Coating, DC motor, L293D Driver Circuit, Programmable Logic controller (PLC), Computer, Slide and Vessel. 1. INTRODUCTION With the rapid changes on industries and information technologies in recent years, some traditional bulk electronic appliances have to be monitored for a long time. All of their control devices such as communication interfaces gradually enter the Internet information era. Control of all equipments has been performed through the use of computers. Most equipment uses PLC (Programmable logic controller) to connect with computer to monitor consuming devices. PLCs are widely used in industrial fields because they are inexpensive, easy to install and very flexible in applications. A PLC interacts with the external world through its inputs and outputs. Since technology for motion control of circuit drives became available, the use of PLC with power electronics in electric machine applications has been introduced in the manufacturing automation 1. Dip coaters are robust computer controlled instruments for precise thin film deposition. We provide solutions for the dip coating of small to large samples in either single or multiple vessels which is suitable for both simple and complex vessel sequencing 2. Since technology for motion control of electric drives became available, the use of PLCs with power electronics in electric machines applications has been introduced in the manufacturing automation 3&4. Many applications of DC motors require besides the motor control functionality, the handling of several specific analog and digital input/output signals, home signals, forward command, reverse commands and on/off 5.In such cases, a control unit involving a PLC must be added to the system structure. This paper presents a PLC-based monitoring and control system for Dip Coating. It describes the design and implementation of the configured hardware and software. The test results obtained on DC motor performance show improved efficiency and increased accuracy in time constant controlled operation. Thus, the PLC correlates and controls the operational parameters to the time set point requested by the user and monitors the DC motor system during manual operation and under automatic conditions. 2. PLC AS A SYSTEM CONTROLLER PLC is a microprocessor-based control system, designed for automation processes in industrial environments. It uses a programmable memory for the internal storage of user-orientated instructions for implementing specific functions such as arithmetic, counting, logic, sequencing, and timing 6&7. A PLC can be programmed to sense, activate and control industrial equipment, incorporates a number of I/O points, which allow electrical signals to be interfaced. Input devices and output devices of the process are connected to the PLC and the control program is entered into the PLC memory (Fig 1). Fig 1: Control Action of a PLC (source 1-8) In our application, it controls through analog/digital inputs and outputs the varying load-constant speed operation of an induction motor. Also, the PLC continuously monitors the inputs and activates the outputs according to the control program. This PLC system is of modular type composed of specific hardware building blocks (modules), which plug directly into a proprietary bus: a central processor unit (CPU), a power supply unit, input-output modules I/O and a program terminal. Such a modular approach has the advantage that the initial configuration can be expanded for other future Luoyang Institute of Science and Technology (120.194.42.194) - 2015/5/27 DownloadInternational Journal of Computer Applications (0975 8887) Volume 57 No.16, November 2012 16 applications such as multi machine systems or computer linking 8. 3. CONTROL SYSTEM OF DIP COATING MODULE The following configurations can be obtained from this setup. PLCs programming is based on the logic demands of input devices and the programs implemented are predominantly logical rather than numerical computational algorithms. The programmed operations work on a straight two-state “forward and reverse” basis and these alternate possibilities correspond to “positive polarity or negative polarity” (logical form) i.e. “+12v or -12v” respectively. In (Fig 2), the block diagram of the experimental system is illustrated. Fig 2: Experimental Setup The following configuration can be obtained from this setup. A. Personal computer for monitoring the status of dip coating. B. PLC- programmable logic controller is programmed with ladder diagram and communicates with PC through RS232 9. C. AC 230V, 50 Hz convert to DC Power supply, simultaneously gives 24V-12AMPS for PLC, 12V and 5V 12 AMPS for L293d driver to operate the function (SMPS) 10&11. D. Circuit board contains L293D PCB (Printed circuit board) design along with controller switch to operate auto and manual 12&13. E. Dip coating model has 12”12” square steel sheet, 12” rod, 10” angle, 2 numbers of slide clamper and vessels clampers. F. The automatic process can be controlled the system of Dip coating module by Auto and Manuals switch are placed inbuilt in the circuit board. 4. HARDWARE DESCRIPTION DC motors run on direct current from a battery or DC power supply. Direct current is the term used to describe electricity at a constant voltage. AC motors run on alternating current, which oscillates with a fixed cycle between a positive and negative value. Electrical outlets provide AC power, when a battery or DC power supply is connected between a DC motors electrical leads, the motor converts electrical energy to mechanical work as the output shaft turns 5&20. These are high quality low cost motors. This motor has a plastic gearbox shell which accommodates metal gears that ensures longer wear and tear. High quality grease is applied inside the gearbox for providing frictionless rotation of the gears 5. DC motor technical specifications shows in Table 1. Table 1. DC motor technical Specifications Connection Range Input voltage 12vdc Output current 500-600mA Rated speed 150rpm Torque of motor 5.5kg-cm Shaft Length 2.4cm Diameter of shaft 6mm Weight of the motor 150gms Mounting Diameter 14mm L293D is a dual H-Bridge motor driver IC L293D can interface two DC motors which can be controlled in both clockwise and anti clockwise direction. L293D has output current of 600mA and peak output current of 1.2A per channel. Moreover for protection of circuit from back EMF output diodes are included within the IC. The output supply (VCC2) has a wide range from 4.5V to 36V, which has made L293D is a best choice for DC motor driver 14.A simple schematic for interfacing a DC motor using L293D (Fig 3). Three pins are needed for interfacing a DC motor (A, B and Enable). For enabled connect 5v VCC to enable pin another 2 pins needed from controller to make the DC motor works. As per the truth table Table.3 mentioned in the fig.3 its fairly simple to program the PLC controller. Its also clear from the truth table of BJT circuit and L293D the programming will be same for both of them, just keeping in mind the allowed combinations of A and B15. We discuss about the programming in ladder diagram as well as functional block diagram for running the DC motor with the help of a PLC controller. Fig 3: Schematic diagram of L293D Luoyang Institute of Science and Technology (120.194.42.194) - 2015/5/27 DownloadInternational Journal of Computer Applications (0975 8887) Volume 57 No.16, November 2012 17 Table 2. Truth Table for L293D Input Output Enable RA2/RA1 RA3/RA0 A,B 1 0 0 Motor Brakes 1 0 1 Runs Reverse 1 1 0 Runs Forward 1 1 1 Motor Brakes The control system is implemented and tested for a wound rotor DC motor, having the technical specifications given in Table 1. This controller is implemented on a PLC modular system. The PLC architecture refers to its internal hardware and software. As a microprocessor-based system, the PLC system hardware is designed and built up with the following modules 16. Central processor unit (CPU) Discrete input module (DIM) Discrete output module(DOM) Analog inputs module (AIM) Analog output module (AOM) Power supply The DC motor machine drives its shaft mechanically and an output voltage is produced, the magnitude of which is proportional to the speed of rotation. Polarity depends on the direction of rotation. The voltage signal from the circuit driver must match the specified voltage range of the (012 V DC). PLC external control circuits are designed using a low-voltage supply of 24 V DC. For the manual control, the scheme is equipped with start, stop push buttons, as well as with a forward and backward direction selector switch (Table 2), all of the described components: a main switch an automatic forward and backward selector through PLC module and for manual forward/backward direction of rotation switch selector as well as the PLC modules are installed in a control panel. The program is downloaded into the PLC from a personal computer (PC) using RS232 serial interface. 5. SOFTWARE DESCRIPTION PLCs offer a flexible, programmable and alternative to electrical circuit relay-based control systems built using analog/digital devices. The programming method used is the ladder diagram method. The PLC system provides a design environment in the form of software tools running on a computer terminal which allows ladder diagrams to be developed, verified, tested and diagnosed. First, the high-level program is written in functional block/ladder diagrams 17. Then, the ladder diagram is converted into binary instruction codes so that they can be stored in random access memory (RAM) or erasable programmable read-only memory (EPROM). Each successive instruction is decoded and executed by the CPU. The function of the CPU is to control the operation of memory and I/O devices and to process data according to the program. Each input and output connection point on a PLC has an address used to identify the I/O bit. The method for the direct representation of data associated with the inputs, outputs and memory is based on the fact of the PLC memory is organized into three regions: Discreet input (I), output relay (O), and internal memory (M). Any memory location is referenced directly using I, O, and M (Table 3). The PLC program uses a cyclic scan in the main program loop such as periodic checks are made to the input variables (Fig 4). The program loop starts by scanning the inputs to the system and storing their states in fixed memory locations (internal memory I). Table 3. PLC configuration CD 20 PLC Pins Available Used Discreet Inputs(I) 6 2 Analog Inputs(I) 4 - Output Relays(O) 8 4 LED Display 3672 Digital display Data Memory(M) 368bits/200 words Fig 4: Flow chart of the main program. The ladder diagram program is then executed rung by-rung. Scanning the program and solving the logic of the various functions rungs determine the output states. The updated output states are stored in fixed memory locations (output image memory O). The output values held in memory are used to set/reset the physical outputs of the PLC. For the given PLC, the time taken to complete one cycle or the scan time is 0-20 ms (Input acquisition time +1 to 2 cycle times) and with a maximum program capacity of 350 blocks /200 words 18. The development system comprises a computer (PC) connected via an RS232 serial port to the target PLC. The computer provides the software environment to perform file editing, storage, printing, and program operation monitoring. The process of developing the program to run on the PLC consists of: using an editor to draw the source ladder diagram program, converting the source program to binary object code which will run on the PLCs microprocessor and downloading the object code from the PC to the PLC system via the serial communication port. The PLC system is online when it is in active control of the machine and monitors any data to check for the correct operation 19. 6. RESULTS The system was tested during operation with test on Dip coating control performance and time period. The PLC monitoring the DC motor operation (Dip coating) and correlates the parameters according to the software. The performance of DC motor supplied from standard 12V and PLC total circuit input 24V network were measured. The experiment control system was operated forward and Start Slid Forward Timer Delay Slid Reverse Stop Luoyang Institute of Science and Technology (120.194.42.194) - 2015/5/27 DownloadInternational Journal of Computer Applications (0975 8887) Volume 57 No.16, November 2012 18 backward respectively +12V and -12V in the two different modes. The experiment flow chart shows in Fig 5. The range of voltage and speed corresponds to design of the PLC hardware and software as described in the previous sections. The rotations versus voltage and time characteristics were studied in the range of 0- 200sec /12V (Table 4). Fig 5: Experimental characteristics with PLC and L293D driver Table 4. Description of PLC and L293D driver characteristics Forward Time delay (Slide in chemical) Reverse 0 - 20s 20 - 80s 80 - 100s 100 - 120s 120 - 180s 180-200s S- Seconds. 7. CONCLUSION Successful experimental results were obtained from the previously describe scheme indicating that PLC can be used in automated system with L293D motor driver and control by PLC proves its high accuracy in time delay regulation at constant speed. The present study revealed that the Dip coating effectiveness with PLC-based control system is affordable and satisfactory. The obtained Dip coating efficiency with PLC control is may be increased as compared to the other microprocessor/microcontroller. Specifically, at high speeds forward, reverse direction the efficiency of PLC-controlled system is increased up to 10-20% as compared to the configuration of the DC motor supplied from a standard network. Despite the simplicity of the control method used, this presents: Constant voltage Very good accuracy in closed-loop control scheme Higher efficiency Timing performance Economically low Since, the Dip coating effectiveness with PLC proved to be a versatile and efficient control tool in industrial automation and research laboratory applications. 8. ACKNOWLEDGMENTS I am deeply indebted to faculties of Department of Electronics and Instrumentation, Bharathiar University for providing the research facilities. 9. REFERENCES 1 S. S. Peng, M. C. Zhou. Ladder Diagram and Petri- Net-Based Discrete-Event Control Design Methods. IEEE Transactions on Systems, Man, and Cybernetics- Part C, Applications and Reviews, Vol.34 No.4 pp. 523-531 Nov. 2004. 2 Ksv Nima Company. Application of dip coating with automation North America, pp1-4, oct2010. 3 G. Kaplan. Technology Industrial electronics IEEE Spectr., vol. 29, pp. 4748, Jan. 1992. 4 B. maaref, S. nasri and P. sicard. Communication system for industrial automation in proc. IEEE int. symp Industrial electronics, vol. 3,pp. 12861291, 1997. 5 Prof. Krishna Vasudevan, Prof. G. Sridhara Rao and Prof. P. Sasidhara Rao. Electrical Machines I Indian Institute of Technology Madras, pp99-122. 6 Programmable Controllers. Part 1: General Information, 1992. 7 British Standard, BS EN 61131-1, 1994. 8 J. G. GiIberl, G. R. Diehl, Application of Programmable Logic Controllers to Substation Control and Protection, IEEE Transactions on Power Delivery, Vol. 9, No. 1, January, USA, pp. 384-388, 1994 9 John W.weebb and Ronald A.Reis Fith. Programmable logic controllers, principles and applications edition2010. 10 Miller Rex. Electronics the Easy Way, 4th ed. Barrons Educational Series, pp. 88-89, 2002. 11Cyril W. Lander. Power Electronics, McGraw Hill, Rectifying Circuits, 3rd edition, chapter 2, 1993. 12 K.H. Buschow. Electronic Packaging: Solder Mounting Technologies, Materials of Science and Technology, Elsevier, ISBN 0-08-043152-6, pages 2708-2709, 2001. 13 R. S. Khandpur. Printed circuit boards: design, fabrication, assembly and testing, Tata-McGraw Hill, ISBN 0-07-058814-7, pp. 373-378, 2005. 14 A.Williams. Microcontroller projects using the Basic Stamp (2nd Ed.). Focal Press, ISBN 978-1-57820-101-3, pp.339-362, 2002. 15 Chuck McManis. Bipolar Junction (BJT) H-Bridges, November, 2003 16 N. Aramaki, Y. Shimikawa, S. Kuno, T. Saitoh and H. Hashimoto, A new architecture for high-performance programmable logic controller, in Proc. 23rd Int. Conf. Industrial Electronics, Control and Instrumentation, vol. 1, pp. 187199,1997 17 Programmable Controllers. Part 2: Equipment Requirements and Tests, 1994. 18 Crouzet Automation. Millenium 3 Standard logic controller specification and its applications” Crouzet pp.1-92, 2006. 19 M. G. Ioannides. Design and Implementation of PLC-Based Monitoring Control System for Induction Motor, IEEE Transactions on Energy Conversion, 19, No: 3 USA, 2004. 20 A.O.Smith. The ACs and DCs of Electric Motors Retrieved 2009-12-07. Luoyang Institute of Science and Technology (120.194.42.194) - 2015/5/27 DownloadInternational Journal of Computer Applications (0975 8887) Volume 57 No.16, November 2012 19 21 JohnW.weebb and Ronald A.Reis. Programmable logic controllers, principles and applications, , fifth edition2010 22 AUTHORS PROFILE G.Madhan received M.Sc and M.Phil degree in Electronics and Instrumentation from Bharathiar University, Coimbatore, Tamil Nadu, and India in 2011 and 2012 respectively. Her research interests include programmable logic controller (PLC), Embedded Systems and wireless communication. G.R.Kandhasamy received his M.Sc degree in Physics from Madras University, Chennai, Tamil Nadu, India, and the M.Phil degree from Bharathiar University in 1992.His area of interest is Special electronics, thin Film, Sensors and Physics. S.Muruganand received his M.Sc degree in Physics from Madras University, Chennai, Tamil Nadu, India, and the Ph.D degree from Bharathiar University in 2002. He is working as an Assistant Professor in the Department of Electronics and Instrumentation, Bharathiar University, Coimbatore, India. His area of interest is embedded systems, PLC, Sensors, Physics and His area of interest is Embedded Systems, PLC, Sensors, Physics and Digital Signal Processing. Luoyang Institute of Science and Technology (120.194.42.194) - 2015/5/27 Download