履帶式起重機(jī)桅桿頂升部分結(jié)構(gòu)及液壓系統(tǒng)設(shè)計(jì)
履帶式起重機(jī)桅桿頂升部分結(jié)構(gòu)及液壓系統(tǒng)設(shè)計(jì),履帶式起重機(jī)桅桿頂升部分結(jié)構(gòu)及液壓系統(tǒng)設(shè)計(jì),履帶式,起重機(jī),桅桿,部分,部份,結(jié)構(gòu),液壓,系統(tǒng),設(shè)計(jì)
14
1.1起重機(jī)簡(jiǎn)介
起重機(jī)是一種用來(lái)起重與空中搬運(yùn)重物的機(jī)械設(shè)備，廣泛應(yīng)用于工礦企業(yè)、車站、港口、倉(cāng)庫(kù)、建筑工地等部門。它對(duì)減輕工人勞動(dòng)強(qiáng)度、提高勞動(dòng)生產(chǎn)率、促進(jìn)生產(chǎn)過程機(jī)械化起著重要作用，是現(xiàn)代化生產(chǎn)中不可缺少的工具。起重機(jī)包括橋式、門式、梁氏和旋轉(zhuǎn)式等多種，其中以橋式起重機(jī)的應(yīng)用最廣。
橋式類起重機(jī)又分為通用橋式起重機(jī)、冶金專用起重機(jī)、龍門起重機(jī)與纜索起重機(jī)等。
橋式起重機(jī)是橋架在高架軌道上運(yùn)行的一種橋架型起重機(jī)，又稱天車。橋式起重機(jī)的橋架沿鋪設(shè)在兩側(cè)高架上的軌道縱向運(yùn)行，起重小車沿鋪設(shè)在橋架上的軌道橫向運(yùn)行，構(gòu)成一矩形的工作范圍，就可以充分利用橋架下面的空間吊運(yùn)物料，不受地面設(shè)備的阻礙。
1.1.1普通橋式起重機(jī)組成部分
（1） 橋架（又稱大車）
橋架是起重機(jī)的基本構(gòu)件，由主梁、端梁、走臺(tái)等部分組成。
（2） 大車移動(dòng)機(jī)構(gòu)
大車移動(dòng)機(jī)構(gòu)由大車拖動(dòng)電動(dòng)機(jī)、聯(lián)軸節(jié)、減速器、制動(dòng)器及車輪等部分。整個(gè)橋式起重機(jī)在大車移動(dòng)機(jī)構(gòu)拖動(dòng)下沿車間長(zhǎng)度方向的導(dǎo)軌移動(dòng)。
（3） 小車
小車安放在橋架導(dǎo)軌上，可沿車間寬度方向移動(dòng)。小車移動(dòng)機(jī)構(gòu)由小車電動(dòng)機(jī)、制動(dòng)器、聯(lián)軸節(jié)、減速器、車輪等部分組成。
（4） 提升機(jī)構(gòu)
提升機(jī)構(gòu)由提升電動(dòng)機(jī)、提升減速器、制動(dòng)器、卷筒、靜滑輪、吊鉤等部分組成。提升電動(dòng)機(jī)經(jīng)聯(lián)軸節(jié)、制動(dòng)輪與減速器聯(lián)接，鋼絲繩另一端裝有吊鉤。當(dāng)卷筒轉(zhuǎn)動(dòng)時(shí)，吊鉤就隨鋼絲繩在卷筒上纏繞而上升或下降，對(duì)于起重量在15t以上的提升機(jī)構(gòu)，一般配備兩套吊鉤上隨著卷筒而獲得上下運(yùn)動(dòng)，隨著小車在寬度方向獲得左右運(yùn)動(dòng)，隨著大車沿車間長(zhǎng)度方向作前后運(yùn)動(dòng)，所以就實(shí)現(xiàn)了重物在垂直、縱向、橫向三個(gè)方向的運(yùn)動(dòng)，將重物移動(dòng)到車向的任一位置。
（5） 駕駛室
駕駛室是操縱起重機(jī)的吊艙，駕駛室一般固定在主梁一端的下面，也有少數(shù)裝在小車下方隨小車移動(dòng)，駕駛室內(nèi)有小車、大車、提升機(jī)構(gòu)的控制裝置及保護(hù)裝置。
1.1.2橋式起重機(jī)的工作原理
起重機(jī)由大車電動(dòng)機(jī)驅(qū)動(dòng)沿車間兩邊的軌道作縱向前后運(yùn)動(dòng)； 小車及提升機(jī)構(gòu)由小車電動(dòng)機(jī)驅(qū)動(dòng)沿橋架上的軌道作橫向左右運(yùn)動(dòng)；在升降重物時(shí)由起重電動(dòng)機(jī)驅(qū)動(dòng)作垂直上下運(yùn)動(dòng)，實(shí)現(xiàn)重物在垂直、橫向、縱向三個(gè)方向的運(yùn)動(dòng)。
1.1.3遙控控制
傳統(tǒng)起重機(jī)得控制方法采用凸輪控制器或采用主令控制器與磁力控制屏控制，凸輪控制器和主令控制器均安裝在起重機(jī)駕駛室內(nèi)，操作人員離控制對(duì)象比較遠(yuǎn)，常因此判斷不準(zhǔn)造成定位不準(zhǔn)，甚至造成失誤?；诖瞬捎眠b控控制裝置，這樣就使操作人員可以在適當(dāng)?shù)淖鳂I(yè)面利用手中的遙控器發(fā)出控制命令，很方便地控制起重機(jī)的工作。
1.2起重機(jī)遙控系統(tǒng)的發(fā)展概況
50年代，各類工業(yè)用遙控系統(tǒng)在歐美開始出現(xiàn)。
60年代，以德國(guó)HBC為代表的遙控系統(tǒng)制造商開發(fā)了專用于起重機(jī)控制的遙控系統(tǒng)，被認(rèn)為是企業(yè)減少勞動(dòng)力，實(shí)現(xiàn)自動(dòng)控制的良好途徑。當(dāng)時(shí)歐洲的制造業(yè)、建筑業(yè)等人手不足的現(xiàn)象越來(lái)越嚴(yán)重，遙控系統(tǒng)的使用漸漸引起人們的重視。
70年代初，采用了與時(shí)分制周期傳送方式并用的方法，增加了操作指令，并實(shí)現(xiàn)了設(shè)計(jì)、制造的標(biāo)準(zhǔn)化。
70年代末，采用了當(dāng)時(shí)最先進(jìn)的CMOS電路，研制出了周期循環(huán)數(shù)字方式的遙控系統(tǒng)，可靠性和安全性有個(gè)很大提高。
80年代，采用了集成電路，開發(fā)出了可靠性更高，可持續(xù)的遙控系統(tǒng)。
90年代初，采用了微處理器和大規(guī)模集成電路，使遙控系統(tǒng)的發(fā)展又上了一個(gè)新臺(tái)階。
近年來(lái)，又研制出了具有自動(dòng)跳頻技術(shù)、自動(dòng)頻率管理技術(shù)和各類總線輸出的遙控系統(tǒng)。
1.3起重機(jī)遙控控制的優(yōu)點(diǎn)
在科學(xué)技術(shù)不段發(fā)展的今天，無(wú)線遙控技術(shù)應(yīng)用已經(jīng)十分廣泛，大到人造衛(wèi)星，小到家用的空調(diào)器、電視機(jī)、音響等都使用遙控技術(shù)來(lái)進(jìn)行操作。遙控技術(shù)的發(fā)展被認(rèn)為是一種現(xiàn)代化的標(biāo)志，它可以充分使人從繁雜的體力勞動(dòng)中解放出來(lái)，隨心所欲地從遠(yuǎn)距離進(jìn)行控制，如：電視機(jī)的遙控可以使人隨意地躺坐來(lái)變換喜歡的電視節(jié)目，使人享受充分的休息。遙控技術(shù)的發(fā)展使人們享受著科學(xué)的魅力。由于遙控技術(shù)可以減低勞動(dòng)強(qiáng)度、提高勞動(dòng)生產(chǎn)率及提高作業(yè)的安全性等方面起著積極的作用，在工業(yè)自動(dòng)化控制中的遙控技術(shù)的應(yīng)用已愈來(lái)愈被人們重視。
日常生活中我們使用的無(wú)線遙控發(fā)射方式多數(shù)為紅外線型，因其成本低，易于人們接受。但由于該控制方式受發(fā)射距離、方向和條件的限制，局限性較大，應(yīng)用在工業(yè)無(wú)線控制領(lǐng)域就顯不足。而目前廣泛用于工業(yè)無(wú)線控制領(lǐng)域的遙控裝置，主流是以無(wú)線信號(hào)進(jìn)行傳輸?shù)姆绞健?
以下就起重機(jī)用無(wú)線遙控系統(tǒng)自身特點(diǎn)、發(fā)展概況、使用優(yōu)勢(shì)和遙控系統(tǒng)分類進(jìn)行簡(jiǎn)單介紹。
1.3.1起重機(jī)使用遙控系統(tǒng)具有以下幾個(gè)優(yōu)點(diǎn)
（1）.節(jié)省人力
a. 對(duì)于橋式、門式起重機(jī)及汽車起重機(jī)等裝卸設(shè)備，其操作掛鉤可由一人承擔(dān)，操作者可直視操作，不需要指揮。
b. 對(duì)于工作效率低的起重機(jī)設(shè)備，一人可同時(shí)管理多臺(tái)起重機(jī)設(shè)備。
c. 可在起重機(jī)操縱同時(shí)，完成與其關(guān)連的輸送帶、加料器、搬運(yùn)車等其它設(shè)備控制和管理。
（2).提高工作效率
a. 由于操作者與地面指揮由一人承擔(dān)，操作者可自行判斷，進(jìn)行作業(yè)，提高了作業(yè)的準(zhǔn)確性及工作效率。
b. 避免了過去操作人員與地面指揮之間的誤解，適用于設(shè)備組裝等精密安裝作業(yè)。
c. 省去了司機(jī)上、下起重機(jī)的所帶來(lái)的諸多不便。
（3).環(huán)境安全的提高
在有毒氣體、高溫、多粉塵和危險(xiǎn)的作業(yè)場(chǎng)地，可選擇環(huán)境好、且安全的位置進(jìn)行操作，操作者的人身安全得到保護(hù)，作業(yè)條件得到改善。
（4）準(zhǔn)確的檢查故障
1.3.2起重機(jī)用無(wú)線遙控系統(tǒng)特點(diǎn)
（1） 可靠性。
遙控系統(tǒng)一旦發(fā)生故障，將影響生產(chǎn)正常運(yùn)行。因此其系統(tǒng)及系統(tǒng)的硬件必須具有高度的可靠性。
（2） 安全性。
遙控系統(tǒng)是起重機(jī)械的控制裝置，如果動(dòng)作有誤，將發(fā)生物損、人傷的事故。因此必須保證遙控系統(tǒng)的百分之百的安全，具有操作者應(yīng)能直接進(jìn)行緊急停車和系統(tǒng)自動(dòng)急停的安全保護(hù)。
（3）抗干擾性強(qiáng)。
能夠不受電焊、電爐及起重機(jī)變頻器等的電磁雜波干擾，能夠在小范圍內(nèi)同時(shí)多臺(tái)使用，互不干擾。
（4）能在惡劣環(huán)境中使用。
必須具有較強(qiáng)的防塵、防煤氣、耐油、抗沖擊等性能。
輕小型便于操作。
（5）發(fā)射系統(tǒng)由操作者攜帶進(jìn)行操作，故應(yīng)體積小、重量輕、攜帶方便。
1.4現(xiàn)有橋式起重機(jī)遙控控制缺陷
起重機(jī)的遙控控制還未完全普及，其主要原因歸結(jié)為目前的遙控接口電路。目前主流遙控接口電路為繼電器—接觸器控制。 起重機(jī)的電氣傳動(dòng)系統(tǒng)多采用繞線式交流電動(dòng)機(jī)，由凸輪控制器直接控制或由主令控制器發(fā)布控制命令給繼電器——接觸器式系統(tǒng)，來(lái)切除電機(jī)轉(zhuǎn)子外串電阻的方式進(jìn)行調(diào)速，并且操作完全集中在吊車的駕駛室中進(jìn)行，傳統(tǒng)遙控操作方式存在以下問題：
1）遙控操作改變了原起重機(jī)的運(yùn)行性能。
為使遙控操作簡(jiǎn)便，遙控操作按鍵一般較少，相應(yīng)地接收機(jī)輸出接點(diǎn)也少。一般的起重機(jī)均有大車、小車、主鉤和副鉤四個(gè)機(jī)構(gòu)，每個(gè)機(jī)構(gòu)至少需要遙控器有7個(gè)控制點(diǎn)，加上啟動(dòng)、急停、點(diǎn)動(dòng)及主鉤快下，則遙控器至少需要32個(gè)控制點(diǎn)，接受機(jī)需要32個(gè)單速按鍵或24個(gè)單雙速按鍵，要實(shí)現(xiàn)全部功能，操作者須同時(shí)操作兩個(gè)以上按鍵，操作者即感到操作繁忙，又會(huì)造成操作者混亂，形成安全隱患，故遙控器通常設(shè)置的輸出點(diǎn)較少，所以用繼電器接觸器接口只能實(shí)現(xiàn)原起重機(jī)的部分功能，通常各機(jī)構(gòu)以快慢速運(yùn)行，失去了原起重機(jī)五檔調(diào)速性能，所以對(duì)遙控技術(shù)的應(yīng)用形成了障礙。
2)可靠性差。
繼電器-接觸器接口電路須有繼電器柜，特別是復(fù)雜的繼電器控制是最易出現(xiàn)故障的環(huán)節(jié)。兩種接口電路需要接觸器柜，由于起重機(jī)經(jīng)常處于頻繁點(diǎn)動(dòng)等重任務(wù)下工作，因此增加了接觸器線圈的損壞，觸點(diǎn)燒損或熔焊、接線松動(dòng)等故障，尤其是觸點(diǎn)熔焊有可能造成成人身和設(shè)備損害的重大事故，因此可靠性差。
3)遙控改造量大，電工維修困難。
兩種接口電路都需要將遙控接口電路串接與原起重機(jī)的保護(hù)電路中，部分并接在各機(jī)構(gòu)控制的主電路中，因此遙控系統(tǒng)需要很多引出導(dǎo)線，這不僅增加了遙控改造施工的工作量，而且也給日后電工維修系統(tǒng)造成困難。
1.5本課題設(shè)計(jì)的意義
橋式起重機(jī)已在冶金行業(yè)內(nèi)廣泛使用，由于行業(yè)特點(diǎn)，冶金企業(yè)中的橋式起重機(jī)常常在高溫、多粉塵、有毒氣和危險(xiǎn)環(huán)境中工作，在橋式起重機(jī)的駕駛室進(jìn)行操作的作業(yè)條件很差，駕駛員的人身安全得不到有效保障。并且有的吊車安裝位置距離地面有30—40m，由于視線不清楚，吊車操作時(shí)必須由地有地面人員的指揮才能進(jìn)行，但有時(shí)由于指揮配合不當(dāng)，存在著很大的事故隱患。
起重機(jī)遙控操作，它改善了操作者的操作環(huán)境，拓寬了人員的視野，增加了操作人員的人身安全，減少了操作人員數(shù)量，調(diào)高了生產(chǎn)效率。
本文以10t橋式起重機(jī)為例，以S7-200PLC+遙控器+減速電機(jī)組成作為遙控接口電路進(jìn)行系統(tǒng)硬件、軟件的設(shè)計(jì)。由該接口電路組成的遙控系統(tǒng)具有安全可靠、操作簡(jiǎn)單、維護(hù)方便、系統(tǒng)成本低?？蓪?shí)現(xiàn)原起重機(jī)全部控制功能。
1.6系統(tǒng)控制的基本思路
充分利用原凸輪控制器控制方式的操作簡(jiǎn)單、維護(hù)容易、工作可靠和PLC控制功能強(qiáng)大的特點(diǎn)．將原凸輪控制器的方向盤去掉，安裝聯(lián)軸器，再裝上減速電機(jī)，由PLC控制電機(jī)的正反方向運(yùn)行，起重機(jī)的運(yùn)行命令由遙控器發(fā)射器發(fā)出．接收機(jī)收到命令后傳給PLC，利用PLC強(qiáng)大的編程功能實(shí)現(xiàn)遙控器的功能擴(kuò)展.根據(jù)按下按鍵的時(shí)間長(zhǎng)短.控制電機(jī)運(yùn)行的轉(zhuǎn)角，實(shí)現(xiàn)各機(jī)構(gòu)的調(diào)速，根據(jù)檢測(cè)元件實(shí)現(xiàn)機(jī)構(gòu)的限位和零位控制。用PLC+減速電機(jī)+ 凸輪控制器+遙控器系統(tǒng)實(shí)現(xiàn)遙控，可用簡(jiǎn)單的操作實(shí)現(xiàn)起重機(jī)的全部功能。
1.7系統(tǒng)控制要求
(1)系統(tǒng)能實(shí)現(xiàn)起重機(jī)原有的全部調(diào)速功能；
(2)遙控啟動(dòng)時(shí)各機(jī)構(gòu)凸輪控制器必須在零位：
(3)各機(jī)構(gòu)分別用2個(gè)按鍵實(shí)現(xiàn)正反方向及調(diào)速的控制：
(4)各機(jī)構(gòu)減速時(shí)按下相反方向按鍵機(jī)構(gòu)減速至零位為止，不能反向啟動(dòng)；若要反向啟動(dòng)，需機(jī)構(gòu)到零位后放開反向鍵，然后再按一次即可；
(5)點(diǎn)動(dòng)控制時(shí)，各機(jī)構(gòu)最高運(yùn)行在第2擋，放開鍵后自動(dòng)回到零位；
1.1 crane profile
crane is a used to lifting and air carrying heavy loads of machinery, equipment, widely used in industrial and mining enterprises, station, port, warehouse, construction sites and other departments. It to reduce labor intensity and improve labor productivity and promoting production process mechanization plays an important role in modern production, is the indispensable tools. Crane including bridge type and gantry, LiangShiHe rotary and so on many kinds of, among them with bridge crane's most widely used.
Bridge type class crane and divided into general bridge crane, metallurgy special crane and longmen crane and cable crane, etc.
Bridge crane bridge in elevated rail running on a bridge cranes, also called cranes. Bridge crane along the bridge on both sides laying in the orbit of an elevated along the longitudinal operation, lifting car on the shelf in bridge laying track horizontal operation, constitutes a rectangular scope of work, can make full use of bridge in the Spaces below hoisting the materials, not to suffer ground equipment obstacles.
1.1.1 ordinary bridge crane component
(1)Bridge (also called cart)
Bridge is the basic components, the crane girder, girders, walking machine components.
(2)Cart mobile mechanism
By cart mobile mechanism cart drag motors, couplings, reducer, brake and wheel etc parts. The whole bridge crane mobile mechanism under the cart along the length direction drag the guide moving workshop.
(3)car
Car in bridge guide rail, can move along the workshop width. By car motor car mobile mechanism, brakes, couplings, reducer, wheels components.
(4)Hoisting mechanism
Hoisting mechanism ascension motors, ascending reducer, brakes, drum, static pulley, hooks components. Ascension by coupling, brake wheel motors with reducer connection, and the other end wire rope with hook. When the drum rotating, hook with the wire rope in rolling around and rising or falling, for lifting weight in the ascension of 15t above, the general equipped with two sets of organization on the hook won movement up and down with rolling across the width, along with the car, get along with left movement cart ront-rear movement length direction workshop, so will achieve weight in vertical, vertical, horizontal three directions movement, a move to any position to the car.
(5)cab
The cabin is manipulating crane, cab in general fixed pod girder end of below, also have a few outfit in the car with the car moving, cab below inside car, cart, hoisting mechanism control devices and protection device.
1.1.2 bridge crane principle of work
Crane cart motor drives by the workshop on both sides of the orbit around longitudinally sports; Vehicles and hoisting mechanism by car motor drives on the shelf along the bridge about make lateral movement track; When lifting heavy objects in by lifting motor drives, realize the vertical movement up and down in the vertical, horizontal, weight of longitudinal three directions sport.
1.1.3 remote control
Traditional crane must adopt CAM controller or control method by using the command controller and magnetic control panel control, CAM controller and Lord command controller are installed in crane operators driving indoor is far away from the control object, often so judgment not cause positioning prohibit, even cause errors. Based on this using remote control device, thus gives operators can be in the hands of the appropriate coolie in a controlled command, remote control easily control crane work.
1.2 crane development survey of remote control system
In the 1950s, the various industrial control system in Europe and America began to appear.
In the 1960s, HBC in Germany as a representative of the remote control system manufacturer develops the special-purpose in crane remote-control system, considered firms to reduce labor, a good way for the realization of automatic control. At that time Europe as the manufacturing and construction short-handed phenomenon more and more serious, the use of remote control system gradually attracted people's attention.
By the early 1970s, when transmitted TNSS with the method with periodic way, increased operating instructions, and realized the design, the manufacture of standardization.
In the late 1970s, adopted the most advanced CMOS circuit, developed a cycle of remote control system of digital mode, reliability and safety have a greatly improved.
In the 1980s, adopted integrated circuits, developed a higher reliability, sustainable remote control system.
By the early 1990s, the microprocessor and large scale integrated circuits, make remote control system development and on a new level.
In recent years, and developed with automatic frequency hopping technology, automatic frequency management technology and various bus output remote control system.
1.3he advantages of crane remote control
In science and technology for development today, wireless remote control technology application has been very extensive, big to satellite, small to household air-conditioner, TV, acoustics are using remote control technology to operate. The development of remote control technology was considered a modern symbol, it can be fully make people from multifarious physical labor liberated from a distance, follow one's inclinationsly control, such as: TV remote control can make people sit to transform lie freely favorite TV program, make the person enjoy sufficient rest. Remote control technology development makes people enjoy a scientific charm. Due to control technology can reduce labor intensity, improve labor productivity and improve the safety of homework plays an active role in industrial automation control, the application of the control technology already more and more attention by people.
In daily life we use wireless remote control means of transmission for infrared linetypes, most for its low cost and easy people accept. But as the control mode, direction and distance by launching the constraint of larger, application, limitations in industrial wireless control field shows insufficient. And now it is widely used in the industry of wireless control areas remote control device, the mainstream is the way for transmission wireless signals.
Under with wireless remote control system of crane characteristics, advantages and development situation, use simple introduction of remote control system classification.
1.3.1 cranes use remote control system has the following a few advantages
(1). Save manpower
For bridge type and gantry crane and automobile crane, loading and unloading equipment, its operation can be borne by one link operator may look operation, need not command.
For work efficiency low crane equipment, one can also manage multiple crane equipment.
But in crane, complete with manipulating and associated conveyer, plus other equipment van distributor, control and management.
(2). Improving work efficiency
Due to the operator and the ground control by one bear operator may decide, and assignments, improve the working efficiency and accuracy of the assignments.
Avoid the past operators and ground command misunderstandings among, apply to equipment assembling etc. Precise installation work.
Tell the driver, under a crane brings a lot of inconvenience.
(3). Environmental safety improvement
In toxic gases, high temperature, dust and dangerous work site, optional choose good environment, and safe operation, the position of the operator's personal safety protected, operation conditions improve.
(4) accurate inspection fault
1.3.2 With wireless remote control systemcrane characteristics
Reliability.
Remote control system once breaks down, will affect the normal operation of production. So the system and hardware must have high reliability.
Safety.
Remote control system of crane control device, if the action that will happen is wrong, the accident loss, wounded. Therefore must ensure that remote control system of 100 percent security, with the operator should be able to direct the emergency stop and automatically abrupt stop safety protection.
(3) strong anti-jamming.
Can not be electric welding, such as electric and crane inverter electromagnetic clutter interference, can in the small scope and multiple use, not interfere with each other.
(4) can use in bad environment.
Must have strong dustproof, gas, oil resistance, impact resistant properties.
Light and small operation is convenient.
(5) launch system is operated by the operator, reason should carry small volume, light weight, easy to carry
1.4 existing bridge crane remote control flaw
Crane's remote control are not completely popularization, the main reason boils down to the current remote control interface circuit. At present the mainstream remote control interface circuit for relays - contactor controlling. Crane electric drive system used more winding type ac motor, the CAM controller directly control or by Lord command controller release control command to relay - contactor system, to resection of motor rotor resistance of the way, and the operation speed totally on the crane in the cockpit, the traditional remote operation way has the following questions:
1) remote operation changed the original crane's performance.
To make remote operation is simple, remote control buttons generally less, correspondingly receiver output contacts are also less. General crane cart, car, are main hook and vice hook four agencies, each agency needs at least remote seven points, plus start, abrupt stop and point move and main hook fast, the remote control under need at least 32 points, accept machines need to be 32 single speed buttons or 24 dual speed key, to realize the full function, the operator must operating simultaneously two or more buttons, the operator that feel operation busy, and will cause confusion, forming operator safe hidden trouble, so remote usually set the output points less, so use relay contactor interface can realize the partial function of the crane, usually agencies to speed speed operation, lost original crane five timings.this performance, so the application of remote control technology to form the obstacles.
2) poor reliability.
Relays - contactor interface circuit must have relay ark, especially complex relay control is the most easy to malfunction link. Two kinds of interface circuit need contactor ark, often in frequent points because crane and other heavy work under dynamic task, hence increasing contactor coils damage, the contacts burning or welded, wiring looseness fault, especially contacts as welding is likely to cause damage to personal and equipment into a major accident, so poor reliability.
3) remote GaiZaoLiang big, electrical maintenance difficulties.
Two kinds of interface circuit all need will pick up and remote control interface circuit string of original crane protection circuit, part and taken up in institutions in the main circuit control, so remote control system requires a lot of lead wire, it not only increased workload of remote modification construction, but also for future electrician maintenance system cause difficulties.
1.5 The significance of this topic design
Bridge crane has been widely used in metallurgical industry, because within the profession characteristic, metallurgical enterprise bridge crane is often in high temperature, much dust, poisonous gas and danger of working environment, in bridge crane operation homework cab driver bad conditions, without effective safeguard the personal safety. And some crane installation position has 30 - from the ground, because 40m sight is not clear, crane operation must have the ground staff by the command, but sometimes can proceed with improper, due to command the exist great potential accident.
Crane remote operation, it improved operator operating environment, and widened the field of vision, personnel increased operating personnel's personal safety and reduce the operating personnel quantity, raise the efficiency.
Taking 10t bridge crane, for example, with s7-200 PLC + remote + deceleration motor as a remote control interface circuit of the system hardware and software design. Composed by the remote control system of interface circuit with safe and reliable, simple operation, easy maintenance, low cost of a system. The crane can realize all control function.
1.6The basic thought of system control
Make full use of the original CAM controller control mode of simple operation, easy maintenance, reliable and PLC control powerful features. Will the original CAM controller, installed coupling, remove the steering wheel gear motor on reload, controlled by PLC motor running, the positive and negative direction by remote control run command crane. Receiver transmitter after receiving orders issued to PLC, using PLC powerful programming function realizes remote function expansion. According to press the button. Control the length of time the motor running corner, realize the agencies, according to the detection speed limit and the organization components control zero. Use PLC + decelerating motors + CAM controller + remote control system implement remote control, simple operation to realize the crane can all the functions.
1.7 system control requirements
(1) the system can realize all the speed adjustment crane original;
(2) remote start-up agencies CAM controller must in zero:
(3) agencies respectively with two buttons realize the positive and negative direction and speed control:
(4) agencies deceleration press the opposite direction key institutions slow to zero so far, cannot reverse launched; If want to reverse startup, need to institutions to zero, then reverse key after release can; click again
(5) the point start control, agencies operating in the second highest block, let go back to zero; automatic key
The second chapter PLC technology introduction
1. PLC overview
Programmable program controller (Programmable Controler), also known as PLC (Programmable Controler) questions, is to Programmable Logic controller. The use of computer architecture, mainly including the CPU, memory, input and output interface and module, communication interface and module, the programmer and power six parts. As shown in figure 4.1 shows, PLC, by bus structure internal instructions and data transmission. External various switch signals, the analog signals, sensor test various signals are as PLC, input variables, by PLC external input terminals their input into the internal registers, by PLC internal logic operations or various other operational treatment to output terminals, as the output variables of PLC, carry out various control field devices
2. The performance index of programmable controller
Programmable controller performance index is more, different manufacturer programmable controller product technical performance each are not identical, each have characteristics. Usually can use the following several performance indicators are described herein.
(1). The I/O points
The I/O points refers to programmable controller composition control system can access the maximum number of input and output signals, can programmable controller external input and output terminals number. Usually, in total points, input and output points, points than input and output point not an alternative.
(2). Scanning speed
General with executive 1000 steps needed time to measure the instruction, the unit for
收藏