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摘 要
我們的生活中都離不開鐵釘。鐵釘，是和我們的生活是密不可分、息息相關的，隨著鐵釘的普遍，鐵釘的制造設備開始盛行，但在日常五金制造行業(yè)，鐵釘的包裝和整理成為急需解決的問題，大量無序的鐵釘如何按照一定的次序或者排列方式排好，進行裝配或者包裝?，F(xiàn)在大部分是靠人手整理，現(xiàn)利用諧波振動的原理，以及分選排序機構的特點，設計出一臺全自動鐵釘整理機，實現(xiàn)自動整理功能
關鍵詞: 無序排列；諧波振動；鐵釘整理
Abstract
Our life cannot do without nails. Is the nail, and our life are inseparable,
is closely related with the common nails, nails, manufacturing equipment manufacturing industry began to flourish, but in daily hardware, nails, packaging and sorting becomes an urgent issue, a large number of disordered nails to accord with the order or arrangement layout, assembly or packaging. Now mostly rely on manpower arrangement, we use principle of harmonic vibration, and sorting sorting machine, designed an automatic nail finishing machine, automatic sorting function.
Keywords: random arrangement; harmonic vibration; finishing nails
目錄
第1章 緒論 1
1.1概述 1
1.2 整理機基礎研究 2
1.3 現(xiàn)有技術條件 2
1.4 產品現(xiàn)狀 2
第2章 設計內容 3
2.1 設計任務 3
2.2 設計要求 3
2.3 設計方案的構想 3。
第3章 設計實現(xiàn) 。
參考文獻 5
致 謝 。
附錄 圖紙列表 。
第1章 緒論
鐵釘有很多叫法，每個人的叫法可能都不同，有人叫成螺釘，有人叫成鐵釘，有人叫成標準件，有人叫成緊固件。雖然有這么多叫法，但意思都是一樣的，都是鐵釘。鐵釘是緊固件的通用說法。鐵釘的原理是利用物體的斜面圓形旋轉和摩擦力的物理學和數學原理，循序漸進地緊固器物機件的工具。
鐵釘在日常生活當中和工業(yè)生產制造當中，是少不了的，鐵釘也被稱為工業(yè)之米?？梢婅F釘的運用之廣泛。鐵釘的運用范圍有：電子產品，機械產品，數碼產品，電力設備，機電機械產品。船舶，車輛，水利工程，甚至化學實驗上也有用到鐵釘。反正是超多地方都有用到鐵釘的。特如數碼產品上面用到的精密鐵釘。DVD，照相機、眼鏡、鐘表、電子等使用的微型鐵釘;電視、電氣制品、樂器、家具等之一般鐵釘;至于工程、建筑、橋梁則使用大型鐵釘、螺帽;交通器具、飛機、電車、汽車等則為大小鐵釘并用。鐵釘在工業(yè)上負有重要任務，只要地球上存在著工業(yè)，則鐵釘之功能永遠重要。
鐵釘之型式，不論是眼鏡用的極小鐵釘或是大型重電工程用之大鐵釘其種類很多。鐵釘之精度通常為6g級(2級，美國規(guī)格“IFI”為2A牙)，建設工程用的粗制螺為1g級。
鐵釘的運用范圍那么廣泛，所以鐵釘市場肯定比較大，需求量肯定相對來說巨大的，而且在鐵釘行業(yè)生產鐵釘廠家定然也比較多。采購們在選擇專業(yè)的鐵釘采購廠家時，肯定需要先了解鐵釘的一些專業(yè)基礎知識，比如說鐵釘分類標準規(guī)范及美式鐵釘規(guī)格表。
1.1傳統(tǒng)鐵釘制造概述
一，鋼材設計??
在緊固件制造中，正確選用緊固件材料是重要一環(huán)，因為緊固件的性能和其材料有著密切的關系。如材料選擇不當或不正確，可能造成性能達不到要求，使用壽命縮短，甚至發(fā)生意外或加工困難，制造成本高等，因此緊固件材料的選用是非常重要的環(huán)節(jié)。?冷鐓鋼是采用冷鐓成型工藝生產的互換性較高的緊固件用鋼。由于它是常溫下利用金屬塑性加工成型，每個零件的變形量很大，承受的變形速度也高，因此，對冷鐓鋼原料的性能要求十分嚴格。?在長期生產實踐和用戶使用調研的基礎上，結合GB/T6478-2001《冷鐓和冷擠壓用鋼技術條件》GB/T699-1999《優(yōu)質碳素結構鋼》及目標JISG3507-1991《冷鐓鋼用碳素鋼盤條》的特點，以8.8級，9.8級鐵釘螺釘的材料要求為例，各種化學元素的確定。?C含量過高，冷成形性能將降低；太低則無法滿足零件機械性能的要求，因此定為0.25％－0.55％。?Mn能提高鋼的滲透性，但添加過多則會強化基體組織而影響冷成形性能；在零件調質時有促進奧氏體晶粒長大的傾向，故在國際的基礎上適當提高，定為0.45％－0.80％。?Si能強化鐵素體，促使冷成形性能降低，材料延伸率下降定為Si小于等于0.30％。?S.P.為雜質元素，它們的存在會沿晶界產生偏析，導致晶界脆化，損害鋼材的機械性能，應盡可能降低，定為P小于等于0.030％，S小于等于0.035％。?B.含硼量最大值均為0.005％，因為硼元素雖然具有顯著提高鋼材滲透性等作用，但同時會導致鋼材脆性增加。含硼量過高，對鐵釘，螺釘和螺柱這類需要良好綜合機械性能的工件是十分不利的。??
二，球化（軟化）退火??
沉頭螺釘，內六角圓柱頭鐵釘采用冷鐓工藝生產時，鋼材的原始組織會直接影響著冷鍛加工時的成形能力。冷鐓過程中局部區(qū)域的塑性變形可達60％－80％，為此要求鋼材必須具有良好的塑性。當鋼材的化學成分一定時，金相組織就是決定塑性優(yōu)劣的關鍵性因素，通常認為粗大片狀珠光體不利于冷鐓成形，而細小的球狀珠光體可顯著地提高鋼材塑性變形的能力。?對高強度緊固件用量較多的中碳鋼和中碳合金鋼，在冷鐓前進行球化（軟化）退火，以便獲得均勻細致的球化珠光體，以更好地滿足實際生產需要。?對中碳鋼盤條軟化退火而言，其加熱溫度多選擇在該鋼材臨界點上下保溫，加熱溫度一般不能太高，否則會產生三次滲碳體沿晶界析出，造成冷鐓開裂，而對于中碳合金鋼的盤條采用等溫球化退火，在AC1＋(20-30%)加熱后，爐冷到略低于Ar1，溫度約700攝氏度等溫一段時間，然后爐冷至500攝氏度左右出爐空冷。鋼材的金相組織由粗變細，由片狀變球狀，冷鐓開裂率將大大減少。?35\45\ML35\SWRCH35K?鋼軟化退火溫度一般區(qū)域為715－735攝氏度；而SCM435\40Cr\SCR435鋼球化退火加熱溫度一般區(qū)域為740－770攝氏度，等溫溫度680－700攝氏度。??
三，剝殼除鱗??
冷鐓鋼盤條去除氧化鐵板工序為剝亮，除鱗，有機械除鱗和化學酸洗兩種方法。用機械除鱗取代盤條的化學酸洗工序，既提高了生產率，又減少了環(huán)境污染。此除鱗過程包括彎曲法（普遍使用帶三角形凹槽的圓輪反復彎曲盤條），噴九法等，除鱗效果較好，但不能使殘余鐵鱗去凈（氧化鐵皮清除率為97％），尤其是氧化鐵皮粘附性很強時，因此，機械除鱗受鐵皮厚度，結構和應力狀態(tài)的影響，使用于低強度緊固件（小于等于6.8級）用的碳鋼盤條。高強度緊固件（大于等于8.8級）用盤條在機械除鱗后，為除凈所有的氧化鐵皮，再經化學酸洗工序即復合除鱗。?對低碳鋼盤條而言，機械除鱗殘留的鐵皮容易造成粒拔模不均勻磨損。當粒拔?？子捎诒P條鋼絲摩擦外溫時粘附上鐵皮，使盤條鋼絲表面產生縱向粒痕，盤條鋼絲冷鐓凸緣鐵釘或圓柱頭螺釘時，頭部出現(xiàn)微裂紋的原因，95％以上是鋼絲表面在拉拔過程中產生的劃痕所引起。因此，機械除鱗法不宜用來高速拉拔。??
四，拉拔??
拉拔工序有兩個目的，一是改制原材料的尺寸；二是通過變形強化作用使緊固件獲得基本的機械性能，對于中碳鋼，中碳合金鋼還有一個目的，即是使盤條控冷后得到的片狀滲碳體在拉拔過程中盡可能的破解，為隨后的球化（軟化）退火得到粒狀滲碳體做好準備，然而，有些廠家為降低成本，任意減少拉拔道次，過大的減面率增加了盤條鋼絲的加工硬化傾向，直接影響了盤條鋼絲的冷鐓性能。?如果各道次的減面率分配不合適，也會使盤條鋼絲在拉拔過程中產生扭轉裂紋，這種沿鋼絲縱向分布，周期一定的裂紋在鋼絲冷鐓過程中暴露。此外，拉拔過程中如潤滑不好，也可造成冷拔盤條鋼絲有規(guī)律地出現(xiàn)橫裂紋。?盤條鋼絲出出粒絲模口上卷同時的切線方向與拉絲模不同心，會造成拉絲模單邊孔型的磨損加劇，使內孔失圓，造成鋼絲圓周方向的拉拔變形不均勻，使鋼絲的圓度超差，在冷鐓過程中鋼絲橫截面應力不均勻而影響冷鐓合格率。?盤條鋼絲拉拔過程中，過大的部分減面率使鋼絲的表面質量惡化，而過低的減面率卻不利于片狀滲碳體的破碎，難以獲得盡可能多的粒狀滲碳體，即滲碳體的球化率低，對鋼絲的冷鐓性能極為不利，采用拉拔方式生產的棒料和盤條鋼絲，部分減面率直控制在10％－15％的范圍內。?
五，冷鍛成形??
通常，鐵釘頭部的成形采用冷鐓塑性加工，同切削加工相比，金屬纖維（金屬留線）沿產品形狀呈連續(xù)狀，中間無切斷，因而提高了產品強度，特別是機械性能優(yōu)良。?冷鐓成形工藝包括切料與成形，分單工位單擊，雙擊冷鐓和多任務位自動冷鐓。一臺自動冷鐓機分別在幾個成型凹模里進行沖壓，鐓鍛，擠壓和縮徑等多任務位工藝。?單工位或多任務位自動冷鐓機使用的原始毛坯的加工特點是由材料尺寸長5－6米的棒料或重量為1900－2000KG的盤條鋼絲的尺寸決定的，即加工工藝的特點在于冷鐓成型不是采用預先切好的單件毛坯，而是采用自動冷鐓機本身由棒料和盤條鋼絲切取和鐓粗的（必要時）毛坯。?在擠壓型腔之前，毛坯必須進行整形。通過整形可得到符合工藝要求的毛坯。在鐓鍛，縮徑和正擠壓之前，毛坯不需整形。毛坯切斷后，送到鐓粗整形工位。該工位可提高毛坯的質量，可使下一個工位的成型力降低15－17％，并能延長模具壽命，制造鐵釘可采用多次縮徑。?1.用半封閉切料工具切割毛坯，最簡單的方法是采用套筒式切料工具；切口的角度不應大于3度；而當采用開口式切料工具時，切口的斜角可達5－7度。?2.短尺寸毛坯在由上一個工位向下一個成型工位傳遞過程中，應能翻轉180度，這樣能發(fā)揮自動冷鐓機的潛力，加工結構復雜的緊固件，提高零件精度。?3.在各個成型工位上都應該裝有沖頭退料裝置，凹模均應帶有套筒式頂料裝置。?4.成型工位的數量（不包括切斷工位）一般應達到3－4個工位（特殊情況下5個以上）。?5.在有效使用期內，主滑塊導軌和工藝部件的結構都能保證沖頭和凹模的定位精度。?6.在控制選料的擋板上必須安裝終端限位開關，必須注意鐓鍛力的控制。?在自動冷鐓機上制造高強度緊固件所使用的冷撥盤條鋼絲的不圓度應在直徑公差范圍內，而較為精密的緊固件，其鋼絲的不圓度則應限制在1/2直徑公差范圍內，如果鋼絲直徑達不到規(guī)定的尺寸，則零件的鐓粗部分或頭部就會出現(xiàn)裂痕，或形成毛刺，如果直徑小于工藝所要求的尺寸，則頭部就會不完整，棱角或漲粗部分不清晰。?冷鐓成型所能達到的精度還同成型方法的選擇和所采用的工序有關。此外，它還取決于所用的設備的結構特點，工藝特點及其狀態(tài)，工模具精度，壽命和磨損程度。?冷鐓成型和擠壓使用的高合金鋼，硬質合金模具的工作表面粗糙度不應大Ra=0.2um,這類模具工作表面的粗糙度達到Ra=0.025-0.050um時，具有最高壽命。??
1.2整理機基礎研究
國內外的研究發(fā)展：
中國真空整理機形成行業(yè)僅10年，基礎相對薄弱，技術及科研力量不足，其發(fā)展相對滯后，在某種程度上拖了五金和整理工業(yè)的后腿。預測到2010年，國內行業(yè)總產值可達到1300億元(現(xiàn)價)，而市場需求可能達到2000億元。如何能夠盡快的趕上并且抓住這個巨大的市場是我們迫切需要解決的問題。
我國真空整理機行業(yè)的發(fā)展現(xiàn)狀
我國真空整理機起步于上個世紀70年代末，年產值只有七八千萬元產品,品種僅有100多種，銷售總額由1994年的150億元增加到2000年的300億元，產品品種由1994年的270種發(fā)展到2000年的3700種。產品水平上了新臺階，開始出現(xiàn)規(guī)?；?、成套化、自動化的趨勢，傳動復雜、技術含量高的設備開始出現(xiàn)?？梢哉f我國的機械生產已滿足了國內的基本需求，并開始向東南亞及第三世界國家出口，如我國2000年的進出口總額為27.37億美元，其中出口額為12.9億美元，比1999年提高了22.2%。在出口的機械品種中以五金真空整理機等設備已開始成套出口。
整理機械行業(yè)的發(fā)展
Optimal Design of Compliant Trailing Edge for
Shape Changing
Abstract: Adaptive wings have long used smooth morphing technique of compliant leading an d trailing edge to improve their aerodynamic characteristics．This paper introduces a systematic approach to design compliant structures to carry out required shape changes under distributed pressure loads．In order to minimize the deviation of the deformed shape from the target shape，this method uses M ATLAB and ANSYS to optimize the distributed compliant mechanisms by way of the ground approach and genetic algorithm (GA)to remove the elements possessive of very low stresses．In the optimization process，man y factors should be considered such as air loads，input displacements，and geometric nonlinearities。Direct search method is used to locally optimize the dimension an d input displacement after the GA optimization。The resultant structure could make its shape change from 0 to 9．3degreesTheexperimental data of the model confirm s the feasibility of this approach．
Keywords： adaptive wing；compliant mechanism；genetic algorithm ；topology optimization；distributed pressure load；geometric nonlinearity
1 Introduction：
As conventional airfoil contours are usually designed with specific lift coefficients and M ach numbers，they could not change in accordance with the environment changing．Siclari and Austin indicated that the variable camber trailing edge would produce the drag about sixty percent less than the conventional fixed camber airfoil
There are three methods used to design able camber wings．Of them．one is conventional hinged mechanism，which，however, will create discontinuities over the wings surface leading to earlier airflow separation an d drag increase． The others are smart material and the compliant mechanism，of which both could realize smooth shape changing．Nevertheless，compared to the compliant mechanism，the smart—material—made actuators have many disadvantages，such as deficient in energy ,slow in response，strong in hysteresis，limited by temperature，and difficult to control too many actuators．Musolff from Industry University of Berlin used Ni—Ti shape—memory—alloy wire to make an adaptive variable camber wing，which could quickly change its shape，but could not perform highly frequent alteration because of its resilience depend en ton the heat exchange with the outside environment。
Compliant mechanism is a kind of one-piece flexible structure，which can transfer motion and power through its own elastic deformation．It is not only flexible enough to deform，but also has enough stiffness to withstand external loads．Thanks to its joint—free nature，it does not have the trouble some problems confronted by conventional mechanism such as friction，lubrication，noise and recoiling，thereby achieving smooth shape changing.
In 1 994，Kota，a professor from University of Michigan，firstly pointed out that compliant mechanism could be used to control static shape changing under the sponsorship of the Air Force Of ice of Scientific Research in USA．Saggere and Kota
suggested a new method to design compliant adaptive structures，which made the least square errors between the shape—changed curve and the target curve as the objective function for optimization．Based on their work，Lu put forward a load path
representation method．However, her work was limited to only linear analysis under consideration of nodal loads．Good[ from Virginia Polytechnic Institute of State University used the compliant mechanism and the Moving Asymptotes method to design the fuselage tail within the allowable range of its tip maximal deflection．Kota and He trick in2004 designed a compliant trailing edge on the base
of the F16s data，which can change from 0。to 15。and obtained a patent．Campanile from German Aerospace Center presented a modal procedure to design synthetic flexible mechanisms for airfoil shape control，and pointed out that the future re—search should take into account the air load and the geometric nonlinearity．Buhl from Riso National Laboratory of the Wind Energy Department in Denmark used the SIM P method and geometrically nonlinear finite element method to design compliant trailing edge flaps．FlxSys Inc in 2006 produced an adaptive compliant wing，which stood the test on the White Knight airplane．The results indicated that the compliant trailing edge could change+10 ．In China，the research of adaptive wing has been concentrated on smart material and conventional mechanism．Few people，it seems，have worked on designing adaptive wings with the compliant mechanism．Yang is an exception．He analyzed the active aero—elastic wings based on the aero—servo—
elasticity technology．Chen and Huang separately investigated the morphing of the compliant leading edge from the viewpoints of discreteness and continuity.
This paper presents a method to design the shape changeable structure by MATLAB and AN—SYS associated with distributed compliant mechanism on the base of the ground structure approach and genetic algorithm (GA)taking into account the external distributed loads and geometric nonlinearity.
2 Optimization Process:
2．1 Defining the trailing edge model and objective function
As shown in Fig．1，both curves represent two ideal shapes of the trailing edge in the different flying states．One side point)of the structure is supposed to be fixed，and the other side point) to be sliding horizontally. Firstly, the design domain should be defined by the initial curve shape．the input location and the boundary conditions．Then．it is divided with abeam element network simulating the bird’s feather as shown in Fig．2．This is termed the partial ground structure method.
Fig．1 Initial shape and target shape Fig．2 Discretization of the design domain
The simplest and most effective way to manufacture the planar compliant mechanism is to use wire—cutting technology．In the optimization pro—gram，all the elements are of rectangular beams with the same width equal to the thickness of the material，every beams height being a design variable．
In order to make the structure’s deformation come close to the target shape curve，the least square error(LSE)between the deformed curve and the target curve is defined as the objective function．LSE is the sum of squares of position differences of various points along the curves Its expression is
where I (=1，2，?，P)is the number of the points along the curves，P is the total number of points．andare the coordinates of it h node on the target and deformed boundary curve respectively．
The constraints are
Where J (=1，2，?， )is the number of elements，miss the tota1 number of elements，，hi the dimension variable，hmin and hmax are the lower and upper bounds of the element beam height for all elements with the value dependent on manufacturing，hb the height of the boundary elements， the maximumnoda1 deformation of the nodes on the curve boundary when the input point is inactive，and should be smaller than[d]to ensure structure stiffness，[d] the allowable maximum displacement when the input point is inactive，O'max the maximum stress of al1 the elements which must be smaller than Tj to prevent yielding，Tj the topology variable equal to 1，or else0 when the element is eliminated．
2．2 GA optimization
GA is an optimization method which simulates the heuristic selection rule in nature，where the fit．test living things have the most chance to survive，but the inferior ones also have the opportunity to exist． Different from the continuous optimization method，it does not require the gradient-based in—formation of the objective function.
Every element could be expressed as a topology variable and a dimension variable． There—fore，each individua1 could be coded as follows
where ，2 is the number of elements except the boundary ones．With the same heights，the boundary elements throughout the optimizing process are
represented by only one variable，hb.
The fitness is the criterion of the GA optimization．It could be transformed from the objective function into
where βis a coefficient deciding the compulsive selection of the betterindividua1．The smaller the value，the more different would be between the two individuals’fitness thus increasing the compulsiveness of choosing the individual of higher fitness．
The selection of control parameters plays an important role in the convergence of the GA．Generally speaking．the cross probability ranges 0．40—0．99；the mutation probability is 0．000 01-0．01．and the number of individuals 1 0．200．
The variable would be updated through the crossover and mutation，so the possible design could generate in the GA process．
2．3 Finite element analysis(FEA)
Because of the limited design variables and the target function，the optimization module of FEA software could not be used to design the compliant morphing mechanism．Therefore，this paper programmed the GA in MATLAB and the FEA in ANSYS．In the FEA，taking only account of geo—metric nonlinearities and the material being of linear elasticity, ANSYS could solve the node displacements and the element stresses．Then by deleting the elements with low stress，the fitness could be calculated．Fig．3 shows the detailed process．
Fig．3 Flowchart of the structural optimization program．
2．4 Second optimization
Although the GA could optimize the topology and dimension simultaneously in a large solution space，the dimension usually could not directly converge to the optimization．In order to solve this problem，after the GA，the Direct Search method
should be used to find the best values of the input displacement and the dimensions of the elements which remain in the results after the GA．
For morphing of compliant mechanism，F(xiàn)ig．3describes the whole optimization process．It mainly contains initialization of the design domain，F(xiàn)EA，GA optimization and second optimization.
3 Presentation of Results:
Adopted from Ref，the sizes of the initial and the target trailing edge are reduced by sixty percent．，I1ab1e 1 lists the design parameters.
Because the displacement is used as the input，the nonlinear analysis could hardly converge and the stress of the initia1 solutions is very large．Which should be considered after thirtieth generation.
Table 1 Design parameters
Fig．4 and Fig．5 illustrate the results from the GA optimization and the second optimization respectively．
Fig．4 Results after the GA optimization Fig．5 Results after the second
optimization．
Form Table 2，it could be found that through the second optimization of the input displacement and the dimension，the LSE is reduced by 1．352 8mmand improved by 3．13％ ．The altered angle is increased by 1．049 3
Table 2 Results after the two optimization
Fig．6 Stability of final optimal structure
Fig．6 shows the influences of the parameters when the outside distributed pressure load changes from 0 to 1 0 N／mm and the input displacement re—mains 1 1．389 7 mm on the optimal structure．It could be seen that the optimal structure has a good stability if the load is kept in the range Of 0—5 N／mm．As the external load exceeds 5 N／mm，the max stress is likely to exceed the yield stress．
Because this optimization program is based on the M ATLAB and ANSYS．in order to verify the results．an attempt is made to introduce the analytical results of the optimized structure into ANSYS and PATRAN respectively, and then a comparison is made between them．As shown in Fig．7 and Fig．8，the two altered shapes are in good agreement：for in ANSYS the tip displacement is 54．97mm and in PATRRAN 54．50mm．The minor difference between them is from the software．
Fig．7 Results of FEA in ANSYS Fig．8 Results of FEA in PATRAN
On the other hand，a model is made by wire—cutting technology to verify the analytical results．The material of the mode1．identical with that of the design，is 5 mm thick．In the experiment，the distributed pressure load is assumed to be zero．The input displacement 11．389 7mm with the required input load 146 N．Fig．9 shows the model and the experimental result．The altered angle is measured9．3。．and the tip displacement 53mm．The altered shape well accords to the optimized result．If a displacement of 11．3897mm is imposed on the model，the theoretical tip displacement is 54．796 mm． Be．cause of the friction there is between the model and the experiment table a tiny difference will take place between the measured data and the calculated results．
Fig．9 The model and experimental result
4 Conclusions：
Proved by the simulation and experiments，the proposed method to design morphing compliant mechanism is effectual in turning out a trailing edge with required morphing effects and ability of with—standing external loads．The combination of MAT—LAB and ANSYS in the optimization renders the program simple and universa1．There is no need for frequent changes of the rigid matrix．It also avoids the complexity of programming the nonlinear FEA and the transforming distributed loads into nodal loads．Using the mixed code，the topology and the dimension could simultaneously be optimized by the GA．Removing the free elements after the FEA could speed up the optimization．The second optimization could improve the GA results．
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