外文翻譯--氣動移載機與PLC控制
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1、外文翻譯資料 氣動移載機與PLC控制 氣動即采用氣泵和氣閥控制氣流,直接控制氣壓和流量,使得空氣發(fā)生振動。 可編程控制器(PLC)是以微處理器為核心,集計算機技術(shù)、自動化控制技術(shù)于一體的一種新型工業(yè)控制系統(tǒng)。PLC采用了典型的計算機結(jié)構(gòu),主要包括CPU、RAM、ROM和輸入/輸出接口電路等。如果把PLC看作一個系統(tǒng),該系統(tǒng)由輸入變量-PLC-輸出變量組成,外部的各種開關(guān)信號、模擬信號、傳感器檢測的信號均作為PLC的輸入變量,它們經(jīng)PLC外部端子輸入到內(nèi)部寄存器中,經(jīng)PLC內(nèi)部邏輯運算或其它各種運算、處理后送到輸出端子,它們是PLC的輸出變量,由這些輸出變量對外圍設(shè)備進行各種控制。
2、 PLC控制系統(tǒng)一般采取易于理解和掌握的梯形圖語言及面向工業(yè)控制的簡單指令,形象直觀,是基于現(xiàn)場總線技術(shù)、完全開放,采用先進的軟硬件技術(shù)。PLC 控制具有結(jié)構(gòu)簡單靈活、抗干擾能力強、安全可靠、安裝便利、故障率低、維護簡單、大幅度節(jié)約使用成本的特點,能滿足各種中小規(guī)模過程控制、順序邏輯控制和數(shù)據(jù)采集任務(wù)需求,已逐漸廣泛用于工業(yè)控制系統(tǒng)中,包括冶金、礦業(yè)、機械、輕工等領(lǐng)域,為工業(yè)自動化提供了有力的工具。 控制工程近期對用于編程過程和機械控制的邏輯設(shè)備進行了一項調(diào)查,雖然計算機和計算機技術(shù)已經(jīng)為各種控制提供了無限的控制可能,但是PLC仍然是其中重要的一部分。在這次調(diào)查中,超過半數(shù)的人在未來的12
3、個月中將擴大其PLC的投入。超過40%的人在未來的投入不少于過去的12個月。PLC的應(yīng)用范圍十分廣泛。在這次300個人參與的調(diào)查中,大部分的PLC都用于機械控制,過程控制緊隨其后,然后是運動控制、批量控制和診斷。大多數(shù)直接用于工廠級(54%),用于OEM的為25%,兩者都是的為17%。? ?在工業(yè)生產(chǎn)流水線中,經(jīng)常要將傳動帶A上的物品搬至傳送帶B上。如果直接人工從事這種重復(fù)性的勞動,枯燥、無味且勞動強度大,容易引起操作工人的疲勞,出現(xiàn)錯誤。而采用氣動機械手按規(guī)定的動作和規(guī)律進行搬運,可以做到快速、準(zhǔn)確、方便,大大的減輕勞動強度,提高生產(chǎn)的自動化程度。氣動機械手這種有規(guī)律的運動,采用PLC來進
4、行控制,可以方便的實現(xiàn)。 機器人作為典型的機電一體化智能設(shè)備.在制造和物流自動化系統(tǒng)中扮演著重要角色。但標(biāo)準(zhǔn)的工業(yè)機器人只不過是一臺具有若干個自由度的智能機電設(shè)備.孤立的一臺機器人在實際工況中沒有任何應(yīng)用價值.只有根據(jù)作業(yè)內(nèi)容、工件形式、質(zhì)量、外形特征和尺寸大小等因素給機器人配以相適應(yīng)的輔助機械裝置如手爪,它才會成為實用的生產(chǎn)設(shè)備.氣動不僅是機器人的主要驅(qū)動方式之一.在要求機器手末端執(zhí)行器動作迅速、結(jié)構(gòu)簡單、控制維護方便、成本較低,而且柔性轉(zhuǎn)換快捷.并具有通用性的裝配和搬運等“拾一放”、傳送動作作業(yè)時,多采用氣動,或氣動與其他傳動控制技術(shù)組合來進一步提高其運動精度和柔性 在作業(yè)空間范圍
5、有限.工作程序相對固定.而且動作頻繁、重復(fù)性強的中小功率工況.采用氣動模塊化機構(gòu)單元的組合來實現(xiàn)機器手作業(yè),更能體現(xiàn)氣動技術(shù)有效取代人手操作實現(xiàn)生產(chǎn)過程合理化和自動化的特征和優(yōu)越性。對氣動機器手的基本要求是能快速、準(zhǔn)確地拾—放和搬運物件.這就要求它們具有高精度、快速反應(yīng)、一定的承載能力、足夠的工作空間和靈活的自由度及在任意位置都能自動定位等特性。設(shè)計氣動機器手的原則是:充分分析作業(yè)對象(工件)的作業(yè)技術(shù)要求.?dāng)M定最合理的作業(yè)工序和工藝.并滿足系統(tǒng)功能要求和環(huán)境條件;明確:工件的結(jié)構(gòu)形狀和材料特性,定位精度要求.抓取、搬運時的受力特性,尺寸和質(zhì)量參數(shù)等,從而進一步確定對機器手結(jié)構(gòu)及運行控制的要求
6、;盡量選定型的標(biāo)準(zhǔn)組件,簡化設(shè)計制造過程.兼顧通用性和專用性.并能實現(xiàn)柔性轉(zhuǎn)換和編程控制。 氣動手爪是目前機器手尤其是搬運、裝配類機器手在抓取技術(shù)中應(yīng)用最普遍的方式.它可實現(xiàn)雙向抓?。孕袑χ?,而且重復(fù)精度高.抓取力恒定.并可方便地配接各種夾具。氣動手爪是機器手與作業(yè)對象間的直接接口,仔細分析、選擇好氣動手爪直接關(guān)系到機器手的工作性能。在實際運行中、手爪的夾持力應(yīng)保證大于所有靜態(tài)和動態(tài)力的總和。PLC的程序運行方式是循環(huán)掃描方式,而非順序執(zhí)行方式,因此任何一個機械手在其條件滿足后即開始動作。各手之間是并行的。機器手是多自由度的開式串聯(lián)結(jié)構(gòu).在空間和時間中的動力學(xué)參數(shù)隨其位形而不斷變化.
7、系統(tǒng)要求的速度高 控制范圍廣 精度高,傳統(tǒng)的單自由度機構(gòu)的控制技術(shù)遠不能滿足這種控制對象 好在氣動機器手多勾點到點的多段定位控制,追求目標(biāo)點的定位精度和多軸同時協(xié)凋有序運動控制,但較少要求高的軌跡精度,從而簡化了對控制系統(tǒng)的要求。 物料的搬運方式具有可抓可吸的多用途功能;氣動系統(tǒng)電磁換向閥采用匯流板集裝方式,減少了占用空間;PLC控制具有單步、自動等多種工作方式。由于氣壓傳動具有氣源使用方便、不污染環(huán)境、動作靈活迅速、工作安全可靠、操作維修簡便以及適于在惡劣環(huán)境下工作等特點,因而在沖壓加工、注塑及壓鑄等有毒或高溫環(huán)境下作業(yè),機床上、下料,儀表及輕工行業(yè)中小零件的輸送和自動裝配等作業(yè),食品包裝
8、及輸送,電子產(chǎn)品輸送、自動插接,彈藥生產(chǎn)自動化等過程中被廣泛應(yīng)用。所以。氣壓傳動是一種易于推廣普及的實現(xiàn)工業(yè)自動化的應(yīng)用技術(shù)。氣動系統(tǒng)的應(yīng)用,引起了世界各國產(chǎn)業(yè)界的普遍重視。 作為氣動系統(tǒng)的控制裝置目前多數(shù)采用可編程控制器(PLC)??删幊绦蚩刂破魇且晕⑻幚砥鳛榛A(chǔ),綜合計算機技術(shù),自動控制技術(shù)和通訊技術(shù)而發(fā)展起來的一種新型、通用的自動控制裝置,在實際應(yīng)用中,控制系統(tǒng)很容易實現(xiàn)。一般是由受控設(shè)備的動作順序和工藝要求,構(gòu)成工步狀態(tài)表,形成梯形圖,再編制PLC指令。 物料搬運系統(tǒng)由左右移動氣缸、復(fù)位進退氣缸、升降氣缸、夾手或真空吸盤、物料塊、傳感器、圓柱導(dǎo)軌、支架、底座、微動開關(guān)等組成。夾手或
9、真空吸盤可以夾住或吸住物料塊,抓取物料的部分采用夾持式和吸附式兩種形式,選用不同的形式,可分別完成工件的抓取和吸附,以適應(yīng)不同種類的物料搬運。夾手采用電磁鐵吸合與斷開方式夾持物料。夾手或吸盤在升降氣缸的作用下可以上下移動;夾手或真空吸盤連同升降氣缸在左右移動氣缸的作用下沿著圓柱導(dǎo)軌可以左右移動;在復(fù)位進退氣缸的作用下將物料塊送回原始位置,為下一個工作周期準(zhǔn)備,以實現(xiàn)循環(huán)。此系統(tǒng)能夠?qū)崿F(xiàn)物料在一個平面內(nèi)的搬運。操作面板安裝在電控箱上,與實驗裝置主體是分離的。PLC可編程序控制器,電磁閥,真空發(fā)生器等均放置在電控箱里。 物料搬運系統(tǒng)具有左右移動、上下移動及對物料的夾緊和放松、推料進退功能,在PL
10、C控制下可實現(xiàn)單步、自動等多種工作方式。另外,物料被夾手搬運完成以后,為滿足連續(xù)動作需要,還必須將此物料運送回原點位置,以供下次搬運需要。系統(tǒng)可完成的各種工作方式如下。單步:可實現(xiàn)上升、下降、左移、右移、夾緊、放松、推料進、推料退等八種點動操作;連續(xù):按下“啟動”按鈕后,夾手從原點位置開始連續(xù)不斷地執(zhí)行搬運物料。物料搬運系統(tǒng)實現(xiàn)的動作:下降→抓料→上升→右移→再下降→松料→再上升→左移→推料進→推料退。在這個系統(tǒng)中,我們只實現(xiàn)一個物料的循環(huán)動作,故在機械手回原點后,需將物料推回原來位置。在PLC控制下可實現(xiàn)單動、連續(xù)動作工作方式。系統(tǒng)上電后,通過旋轉(zhuǎn)按扭選擇是單動還是連動,如果是單動則執(zhí)行單動
11、程序,否則執(zhí)行連動程序。單動工作方式:利用按鈕對夾手每一動作單獨進行控制。連續(xù):按下啟動按鈕,夾手從原點開始,按工序自動循環(huán)工作,直到按下停止按鈕,夾手在完成最后一個周期的工作后,返回原點,自動停機。 基于PLC控制的物料搬運系統(tǒng)能夠?qū)崿F(xiàn)物料的自動循環(huán)搬運。此系統(tǒng)既可以使用夾手夾持物料,又可以使用真空吸盤吸附物料,具有多種用途功能;氣動系統(tǒng)的電磁換向閥采用匯流板集裝,減少了占用空間;在PLC的控制下可以實現(xiàn)單動和連動兩種執(zhí)行方式,完成物料的搬運。 對于中小型企業(yè), 由于資金和技術(shù)的限制,不可能一次性配備完整的控制系統(tǒng),如DCS系統(tǒng)。而PLC是通用的控制器. 標(biāo)準(zhǔn)的積木式硬件結(jié)構(gòu),模塊化的軟
12、件設(shè)計。可根據(jù)控制范圍可大可小、可簡可繁、采用通用的IBM工控機或兼容機、配套商業(yè)化的上位監(jiān)控軟件包或掛在相應(yīng)的工作站上, 實現(xiàn)設(shè)備操作、回路控制、畫面顯示等功能, 靈活簡便、節(jié)省投資。因此,以PLC為基礎(chǔ)的 過程控制系統(tǒng)可以構(gòu)成一種便于用戶自行組織的完整產(chǎn)品。 Air operated moves the carrier vehicle and the PLC control Air operated namely uses the air pu
13、mp and the air valve control air current, the positive governing barometric pressure and the current capacity, enable the air to have the vibration. The programmable controller (PLC) is taken the microprocessor as the core, collection computer technology, the automated control technology in a body
14、one new industry control system. PLC has used the model computer structure, mainly includes CPU, RAM, ROM and the input/ Output connection electric circuit and so on. If regards as PLC a system, this system is composed by the input variable -PLC- output variable, the exterior each kind of switching
15、signal, the simulated signal, the sensor examine the signal took PLC the input variable, they input after the PLC exterior post to the internal register in, after the PLC interior logic operation or other each kind of operation, processing delivers the output terminal, they are the PLC output variab
16、le, carries on each kind of control by these output variables to the auxiliary equipment. The PLC control system adopts generally easy to understand and to grasp trapezoidal chart language and face industry control simple instruction. The image is direct-viewing, is based on the field bus technolog
17、y, opens completely, and uses the advanced software and hardware technology. The PLC control has the structure simply nimble, the anti-jamming ability strong, safe reliable, installs the convenience, the failure rate lowly, the maintenance is simple, large scale saves the use cost the characteristic
18、, can satisfy each kind of center small scale process control, the smooth logic control and the data acquisition duty demand, widely has used in gradually in the industry control system, including domain and so on metallurgy, mining industry, machinery, light industry, has provided the powerful tool
19、 for the industrial automation. The control engineering in the near future to will use in the logical equipment which programmed the process and the machinery controls carrying on an investigation, although the computer and computer technology already provided the infinite control for each kind of
20、control to be possible, but PLC still was a important part. In this investigation, it will surpass half number of people to expand its PLC in the future 12 months the investment. It will surpass 40% person in the future investment many in the past 12 months. The PLC application scope is extremely wi
21、despread. In this 300 individual participation investigation, majority of PLC all uses in the machinery control, the process control follows closely after that, then is the movement control, the batch control and the diagnosis. The majority uses in directly the factory level (54%), uses in OEM is 2
22、5%, two all is 17%. In the industrial production assembly line, must move frequently the transmission belt A on goods to conveyer belt B on. If direct artificially is engaged in this kind of duplicated work, arid, tasteless also labor intensity big, is easy to cause operates worker's weariness, ap
23、pears the mistake. But uses the air operated manipulator carries on the transporting according to the stipulation movement and the rule, may achieve fast, accurate, is convenient, big reduces the labor intensity, enhances the production the automat city. Air operated manipulator this kind of orderly
24、 movement, uses PLC to carry on the control, and may facilitate realization. The robot sets an example the integration of machinery intelligence equipment. flows in the automated system in the manufacture and the thing to act the strong character. But the standard industry robot only is has certain
25、 degrees of freedom an intelligent electromechanical device. Isolation robot in the actual operating mode is not any application value. only then according to factor and so on work content, work piece form, quality, contour characteristic and size matches to the robot by the auxiliary machinery inst
26、allment like hand fingernail which adapts, it only then can become the practical production equipment. air operated not only is 1.th robot main drive type is quick-moving requesting machinist terminal execution quick-moving, the structure simple, the control maintenance convenient, the cost to be l
27、ow, Moreover the flexible transformation quick. and has the versatile assembly and the transporting and so on "ascends when puts", the transmission movement work, uses air operated, or air operated combines with other transmission control technologies further increases its movement precision and the
28、 flexibility relatively fixed. Moreover the movement is frequent, the duplicated strong center low power operating mode in the work space scope limited, working routine, and uses the air operated modular organization unit the combination to realize the machinist work, can manifest the air operated t
29、echnical effective substitution manpower operation realization production process Taiwan physics and chemistry and the automated characteristic and the superiority. Is can be fast to the air operated machinist's basic request, accurately ascend to put requests them with transporting thing. To have t
30、he high accuracy, the rapid reaction, the certain bearing capacity, the enough working space and the nimble degree of freedom and in the free position all can characteristic and so on automatic positioning. Designs the air operated machinist's principle is: Full analysis work object (work piece) the
31、 work specification, and draws up the most reasonable work working procedure and the craft. And satisfies the system function request and the environmental condition; explicit: The work piece structure shape and the materials behavior, the pointing accuracy request. capture, time the transporting st
32、ress characteristic, the size and the quality parameter and so on, thus further determines to the machinist structure and the operating control request; The as far as possible designation standard module, the simplification design manufacture process. Pay attention to both versatility and special-pu
33、rpose, and can realize the flexible transformation and the programming control. The air operated hand fingernail is the present machinist transports, the assembly class machinist in particular in captures in the technology to apply most universal way. it to be possible to realize bidirectional capt
34、ures, voluntarily to the center, moreover the redundant precision high. Capture the strength to be constant. and may conveniently match meets each kind of jig. The air operated hand fingernail is direct connection between the machinist and of the work object, the careful analysis, chooses the good a
35、ir operated hand fingernail to relate directly to machinist's operating performance. In the actual movement, the hand fingernail supports on both sides the strength to be supposed to guarantee is bigger than all static and the dynamic strength sum total. The PLC procedure movement way is circulates
36、the scanning way, but the non- order carries out the way; therefore any manipulator satisfies after its condition namely starts the movement. Between various is parallel. The machinist is the multi-degrees of freedom open the type series structure. But changes the system request speed high control a
37、rea broad precision unceasingly in spatial and the time dynamics parameter along with its configuration high, the traditional single degree of freedom organization control technology is far cannot satisfy this kind of controlled member to be good because of the air operated machinist cancels much to
38、 the multistage localization control, the pursue target point pointing accuracy and multiple spindle at the same time cooperates weakly to have the foreword movement control, but little requests the high path precision, thus simplified to the control system request. The material mode of transport h
39、as the multipurpose function which may grasp may attract; The pneumatic system electromagnetism cross valve selects the afflux board collection attire method, reduced has taken the space; The PLC control has, is on foot automatic and so on the many kinds of work way. Because the pneumatic actuator h
40、as is angry the source easy to operate, does not pollute the environment, the movement nimbly rapid, the job safety reliable, the operation service is simple. And is suitable for under the adverse circumstance characteristic and so on work, thus in the ramming processing, casts and the compression c
41、asting and so on virulent or the high temperature environment is mean industry, on the engine bed, the yummy treats, the measuring appliance and in the light industry profession small work and so on components transportation and automatic assembly, food packing and the transportation, the electronic
42、 products transportation, automatic peg grafting, process and so on ammunition in production automation is widely applied. Therefore. The pneumatic actuator is one kind easy to promote popularly realizes the industrial automation application technology. The pneumatic system application caused the va
43、rious countries industrial field to take generally. Most uses the programmable controller at present as the pneumatic system control device (PLC). The programmable foreword controller is take the microprocessor as a foundation, comprehensive computer technology, the automatic control technology
44、 and the communication technology but develop one kind new, general automatic control device, in the practical application, the control system is very easy to realize. Is generally by is controlled the equipment the sequence of operation and the technological requirement, constitutes the labor step
45、of condition table, forms the trapezoidal chart, again establishes the PLC instruction. The material transporting system moves the air cylinder, the replacement onset and retreat air cylinder by about, rises and falls the air cylinder, clamps the hand or the vacuum cup, the material block, the sens
46、or, the column guide rail, the support, the foundation, the microswitch and so on is composed.Clamps the hand either the vacuum cup may grip or hold the material block, the capture material part uses the clamp type and the adsorption type two forms, selects the different form, may complete the work
47、piece separately the capture and the adsorption, adapts the different type material transporting.Clamps the hand to use the electro-magnet to attract gathers with separates the way clamp material.Clamps the hand or the sucker in rises and falls the air cylinder under the function to be possible to r
48、eciprocate; Clamps the hand or the vacuum cup together with rises and falls the air cylinder to move the air cylinder in about under the function to be possible to control along the column guide rail moves; In under the replacement onset and retreat air cylinder function the material block back init
49、ial position, for the next action cycle preparation, realizes the circulation.This system can realize a material in plane transporting.Operates the kneading board to install in the electrically controlled box, is separates with the test installation main body.The PLC programmable controller, the sol
50、enoid valve, the vacuum generator and so on lays aside in the electrically controlled box. About the material transporting system has moves, reciprocated and to the material clamp and the relaxation, pushes the material onset and retreat function, may realize on foot, and so on automatically under t
51、he PLC control many kinds of working.After moreover, the material is clamped the hand transporting completes, for satisfies continuously acts the need, but also must ship this material the zero point position, will supply the next time to transport the need.The system may complete each working is as
52、 follows.On foot: May realize the rise, the drop, the left shift, the right lateral, the clamp, the relaxation, pushes the material to enter, to push the material to draw back and so on eight kind of spots to move the operation; Continuously: After presses down “the start” the button, clamps the han
53、d to start from the zero point position continuously to carry out the transporting material.Material transporting system realization movement: The drop -> stresses the material -> rise -> right lateral -> to drop -> the loose material -> to rise again -> the left shift -> to push the material again
54、to enter -> pushes the material to draw back.In this system, we only realize a material cyclic action, therefore returns to the zero point after the manipulator, must drive back the homing position the material.May realize the single acting under the PLC control, act continuously the working.On afte
55、r the system the electricity, according to turns the choice through revolving is the single acting or the gearing, if is the single acting carries out the single acting procedure, otherwise carries out the gearing procedure.Single acting working: To clamps hand each movement using the button alone t
56、o carry on the control.Continuously: Presses down the start button, clamps the hand to start from the zero point, according to the working procedure autocycle work, until presses down the pause button, clamps the hand after to complete last cyclical the work, returns to the zero point, auto-stop. Ca
57、n realize the material autocycle transporting based on the PLC control material transporting system.This system both may use clamps the hand clamp material, and may use the vacuum cup adsorption material, has the multiple functions function; The pneumatic system electromagnetism cross valve uses the
58、 afflux board containerization, reduced has taken the space; May realize the single acting and the gearing two execution way under the PLC control, completes the material the transporting. Regarding small and medium-sized enterprise, as a result of fund and technical limit, not impossible disposable
59、 equipment integrity control system, like DCS system.But PLC is the general controller. Standard building block system hardware architecture, modular software design.May according to the control area be possible to be possible small, to be possible greatly Jan Kefan, to use the general IBM labor to
60、control machine or the compatible machine, the necessary commercialization on position monitoring software package or hangs on the corresponding workstation, realizes functions and so on equipment operation, return route control, picture demonstration, nimble simple, saves the investment.Therefore, as the foundation process control system may constitute one kind take PLC the complete product which is advantageous for the user to organize voluntarily. 10
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