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麗 水 學 院 畢業(yè)設計（論文）外文翻譯 （20 13 屆） 題 目 連桿蓋鉆孔專用設備的設計 指導教師 朱曉虹 院 別 工學院 專 業(yè) 機械設計制造及其自動化 班 級 機自091 學 號 09105010125 姓 名 王磊 2013 年 3 月 25 日至 2013 年 5 月 19 日共 8 周 附件1： 立式軸承座鉆孔組合機床設計 摘 要：論述了立式軸承座鉆孔組合機床設計的基本步驟，以及包括此類組合機床設計所要注意點。 關鍵詞：立式軸承座鉆孔組合機床 設計 1 分工序、定工位 生產類型分析 此次設計的立式軸承座鉆孔組合機床，其所加工的零件在汽車中應用十分廣泛，應該屬于大批量生產項目，所以在設計時應注意到盡量使加工簡單，但又不影響加工質量。 加工方案的制定 劃分工序要考慮到生產的規(guī)模、加工的精度、所用機床的特點、機床負荷情況等。 劃分工序可以有兩種趨向：工序集中和工序分散。 工序的集中分散各有其長處，一般說來，在大批量生產中以提高生產率為主，需廣泛采用多刀、單軸與多軸自動或半自動機床，多軸龍門銑床、組合機床等，故采取工序集中可以獲得突出的效果。 此次設計的軸承座鉆孔組合機床很大程度上使各工序盡量集中，發(fā)揮組合機床的優(yōu)點，同時使各種誤差減小到最低限度。 由于此設計中所加工的零件10 個孔中部分孔距離太近，不便于加工，所以分開為兩個工位完成，然后進行零件位置轉換。 主要工位經分析選取以下方案：1)裝卸、夾緊；2)鉆7個孔f13.5；3)鉆3個孔一個為f14，鉆2個螺紋底孔f14，孔號為8、9；4)鉆橫向孔f14；5)擴鉸7個孔f14.5；6)攻絲。 2 復合刀具的切削用量的計算 切削用量的特點 組合機床的正常工作與合理地選用切削用量，即確定合理的切削速度和工作進給量有很大的關系。 切削用量選的恰當，能使組合機床減少停車損失，提高生產效率，延長刀具壽命，提高加工質量。 導套設計 被加工7個孔直徑為14.5 ，加工孔的直徑與導套長度，導套內徑尺寸，上下偏差以及孔軸線理想位置的偏移的關系。 1～7號孔，以及8～10號孔和底孔的直徑為14.5 mm ，它所需要的導套長度為(32～40)mm ，內徑尺寸偏差為+0.016～+0.034 ，孔軸線理想位置偏移為(0.15～0.20)mm。 孔加工切削用量計算 用高速鋼鉆頭加工此鑄件 HB=204(鉆1～7號孔，Ⅱ工位；鉆8～10號孔，Ⅲ工位)；鉆頭直徑：14.5mm；切削用量：v=(10～18)m/min，s=0.2mm/r，轉速350r/min。 用高速鋼鉆頭鉆橫向孔f16(Ⅳ工位) 加工直徑：16mm；切削用量v=(10～18)m/min；s=(0.18～0.25)mm/r；轉速350r/min。 用硬質合金擴孔鉆擴鉸孔1～7號孔(Ⅴ工位) 在Ⅴ工位上，擴鉸7個孔時，采用擴鉸復合刀具，進給量按擴孔鉆選擇，切削速度按鉸刀選擇，而且進給量應按復合刀具最小直徑選用允許值的上限，切削速度則按復合刀具最大直徑選用允許值的上限。 加工直徑：14.5mm；切削用量：v=(8～10)m/min，s=0.25mm/r，轉速280r/min；擴孔鉆刀桿及導向部分的公稱直徑d+0.08；擴孔鉆公差：-0.036；刀桿導向部分公差：-0.006～-0.0017；導套內徑公差：+0.024～0.006。 孔加工常用工序間余量 擴孔直徑為10～20，直徑上的工序余量為(1.5～2.0)mm；鉸孔直徑為10～20，直徑上的工序量為(0.10～0.20)mm(以上切削用量的選擇由東風汽車公司設備制造廠設計科提供資料)。 3 部件選用 功率選擇標準 動力部件用以實現(xiàn)切削刀具的旋轉和進給運動或只用于進給運動，此機床實現(xiàn)了切削刀具旋轉和進給運動兩項內容。 每一種規(guī)格的動力頭都有一定的功率范圍，根據(jù)所計算出的切削功率及進給功率之需要，并適當提高切削用量的可能性，選用相應規(guī)格的動力頭，公式如下： N動>(N切+N進)/hkW。 式中：N動為動力頭電機功率；N切為切削功率，按各刀具選用的切削用量，由“組合機床的切削力及功率計算公式”中已求出；N進為進給功率，對于液壓動力頭就是進給油泵所消耗的功率，一般為(0.8～2)kW；h為傳動效率，當主軸箱少于15根時，h=0.7，多于15根時，h=0.65。 機床實際功率 此立式組合機床左右分兩個電機帶動兩個多軸箱進行加工。對于左半部分多軸箱刀具，在加工1～7號孔以及Ⅲ工位加工10號孔時其功率總和： N/kW=0.29×7+0.283=2.313 因為左主軸箱少于15跟鉆頭，所以 h=0.7，N/kW=2.313/0.7=3.3 對于右半部分多軸箱刀具，在Ⅴ工位擴鉸1～7號孔以及攻絲，鉆頭的實際功率： 　　 N/kW=0.1427×7=1.0 　 因為右主軸箱少于15根鉆頭，所以 　　 h=0.7，N/kW=1÷0.7=1.43 選用電機 由于此機床在驅動方面沒有特殊的要求，選用普通也是最可靠的Y系列電機，它是封閉自扇冷式鼠籠型三相異步電動機，取代J02系列的更新?lián)Q代產品。 左半部分所需功率為3.3kW，查Y系列三相異步電動機表，選用Y123S24型號的電機，額定功率為5.5kW，選用此型號電機比較合適。 右半部分所需功率為1.43kW，查Y系列三相異步電動機表，選用Y112M26型號的電機，額定功率為2.2kW，選用此型號電機比較合適。 4 夾具設計 軸承座鉆孔組合機床夾具分析 根據(jù)工件不同的生產條件，可以有各種不同的安裝方法：a)找正安裝法；b)夾具安裝法。 基本定位原理分析 這里討論6點定位中，6個自由度的消除，以便找出較合適的定位夾緊方案。一個物體在空間可以有6個獨立的運動，即沿X、Y、Z軸的平移運動，分別記為X1、Y1、Z1；繞X、Y、Z軸的轉動，記為X2、Y2、Z2，習慣上，上述6個獨立運動稱作6個自由度。如果采用一定的約束措施，消除物體的6個自由度，則物體被完全定位。例如討論長方體工件時，可以在底面布置3個不共線的約束點，在側面布置2個約束點，在端面布置一個約束點，則底面約束點可以限制X2、Y2、Z23個自由度，側面約束點限制X1、Z12個自由度，端面約束點限制Y1這個自由度，就完全限制了長方體工件6個自由度。夾緊力“兩要素”，方向與作用點 夾緊力方向應朝向定位元件，并使所需的夾緊力最小。 確定夾緊力作用點的位置時應不破壞定位。夾緊力作用點的位置應盡可能靠近加工部位，以減小切削力繞夾緊力作用點的力矩，防止工件在加工過程中產生轉動或震動。應保證夾緊變形不影響加工精度。夾緊力作用點數(shù)目應使工件在整個接觸面上受力均勻，接觸變形小。 定位夾緊方案的確定 此零件屬于空心圓形鑄件，一般的定位元件有V形塊、定位套筒作半圓形定位，如果選用V形塊定位的話，在Z軸方向移動以及繞X、Y軸旋轉的自由度已經消除，在鉆頭進行加工時，繞Z軸轉動的自由度卻無法消除，所以用V形塊定位的方案是行不通的。如果利用半圓形定位，其結果和用V形塊是一樣的，都無法使工件在繞Z軸的方向上穩(wěn)定，最后決定利用定位套筒定位。 環(huán)形套筒以H7/K6或H7/js6的過度配合裝入夾具，零件放入套筒后，在X、Y方向的自由度消除，同時采用壓板的方法;利用球頭螺栓使壓板緊壓住工件體。 在此壓板的作用下，沿X軸旋轉X2，以及沿Z軸旋轉Z2和沿Z軸方向Z1自由度都被限制。所以在此套夾具的作用下，X1、Y1、Z1、X1、Y1等自由度完全被消除，而在壓板的壓力作用下，零件和刀具之間強大的摩擦力，以及在加工過程中軸向力的相互抵消，在Z的自由度也被消除。當進行到Ⅳ工位，加工橫向孔時，X1、Y1、Z1的自由度已被消除，X2、Y2方向自由度也已被消除，在Z2方向上，由于壓板的作用使工件在Z2方向的自由度也消除了。 5 攻絲裝置 在組合機床上攻制螺紋時，根據(jù)被加工零件加工部位的分布情況和工藝要求等，常用的攻絲方法有3種：采用攻絲動力頭攻絲，采用攻絲裝置攻絲和采用活動攻絲模板攻絲。 在此設計中，右半部分完成Ⅴ、Ⅵ工位的加工。電機只有5.5kW的功率，故綜合考慮選用攻絲裝置攻絲。當整臺機床或機床的某一面全部用于完成攻絲工序時，廣泛地采用了攻絲裝置。 攻絲裝置由攻絲主軸箱和攻絲靠模頭組成，由于靠模螺母和靠模桿是經磨削并配研的，其螺距要求與所需加工螺孔的螺距保持一定關系，并設有螺距誤差補償機構。因此利用攻絲裝置進行攻絲可以達到較高的精度。 6 組合機床冷卻裝置 機床冷卻液除對刀具和工件起冷卻作用外，還能在金屬表面形成潤滑薄膜，起到潤滑作用。一些冷卻液中含有碳酸鈉，亞硝酸鈉等防銹劑，它們在金屬表面形成膠狀吸附膜或氧化物薄膜，又能使金屬免受腐蝕的作用。因而選擇冷卻液時，應根據(jù)組合機床完成工藝、加工方法、刀具材料以及被加工零件的材料來決定。 在加工鑄鐵件時，由于鑄鐵本身含有石墨能自身潤滑，一般都不加冷卻液。在大量生產中有時為了減少加工中的鐵粉飛揚，也增加冷卻系統(tǒng)，以改善操作條件。有時可采用蘇打水，5%的乳化液，其乳化劑的主要成分可以是氧化油膏或硫化切削油。其配方為：油膏2%～5%，粗加工取低值，精加工取高值;亞硝酸鈉0.2%～0.25%;無水碳酸鈉0.2%～0.3%。在鑄鐵工件上攻絲時，則都采用潤滑液，以提高表面光滑度，減少功率的消耗。通常采用煤油，亦可采用硫化切削液及混合油等。 冷卻液的流量應根據(jù)刀具的形式、直徑的大小、加工方法、切削用量等具體條件確定，組合機床的設計使用經驗表明，對鏜刀、鉆頭以及銑刀一類刀具，每根刀具冷卻液的平均流量約為(2～6)L/min。國外資料推薦按加工直徑選擇，每把刀具的冷卻液流量。 7 工作循環(huán)說明 一臺組合機床，其工作循環(huán)常常是比較復雜的，不僅有好幾個動力頭按不同的循環(huán)進行工作，而且這些循環(huán)還需其他部件，如移動工作臺，回轉工作臺以及鼓輪等配合動作。各動力部件借助程序控制擋鐵，按規(guī)定順序進行工作。工作循環(huán)應當盡可能的簡單而且控制元件應該少，否則機床的制造成本加大，安全性能也會降低。 本組合機床適合在大批量生產中使用，生產效率大大提高。為了降低成本，應多選用復合刀具，盡量做到一次成形，減少裝夾次數(shù)。選擇合適的電機和動力頭，選擇恰當?shù)那邢饔昧亢颓邢魉俣取? 附件2： Design of the Vertical Bearings Hole Drill Bed Zhang Yinbao Liu Shaowei Abstract: This essay narratives the basic steps of upright axle bearing seat borehole combination and main points of designation of the combination machine tools Keywords: The vertical axle bearing seat drills constituting a machine tool Design 1 Allotting working procedure, booking the labor place Production type analysis The vertical axle bearing seat machine tools designed this time and parts processed extensively apply to the use of the automobile and belong to the mass production project, therefore we should pay attention to that when designing we should make the process as simple as we can without affecting the quality. Working out the process scheme Dividing working procedure needs to think the production scale, accuracy, characteristics of a machine tool used and the situation of the machine tool loaded. Dividing working procedure has two kinds of tendencies: concentrating the working procedure and s dispersing working procedure. The working procedure concentrated and the dispersed have their own strong points. Generally speaking, improving efficacy in mass production need adopt multicut , single axis and polyaxis automation or semi-automatic machine tool broadly. The poleaxis and the machine tool adopt concentrating working procedure in order to gain outstanding effect. That the axle bearing seat machine tools designed this time uses concentrating working procedureas much as possible in order to bring the merits of the combination machine tools into full play and makes the various error diminution arrive at the floor at the same time. Because the distances between of the ten parts are too close, it is inappropriate to process. So the place is completed by two labors, then changes the locations of the parts. The main labor place chooses the following scheme after analysis: 1) loads and unloads , clamps; 2) drills 7 holes f13.5; 3) drill 3 holes one is f14 , the other 2 are thread bottom holes f14 , hole number is 8 , 9; 4) drills transverse direction hole f14; 5) expands hinge 7 holes f14.5; 6) tapping. 2 Calculation of compound cutter cutting dosages Cut the dosages characteristics The regular work of a machine tool has very big something to do with to selecting and using cutting dosages reasonably, which means that choosing the appreciate cut speed and the job feed amounts ascertain rational cutting. Choosing appreciate cut dosages can make the combination machine tool cut down the parking loss, improve production efficiency, prolong the cutter increased longevity, and improve the quality of processing. Designing the lead cover The diameters of the 7 holes processed are is 14.5mm, followed the lead cover length, the internal diameter dimension of it, deviation and shift relations of the ideal hole axis location. The cover lengths of holes from No.1 ~ NO.7 and NO.8 ~ NO. are (32 ~ 40) mm and the bottom hole diameter are 14.5 mms, inside diameter dimension deviation is 0.016 ~ + + 0.034, ideal hole axis location offsets for (0.15 ~ 0.20) mm. Calculation of processing a hole dosages Use high-speed steel drill to process this casting HB = 204 (drill NO.1 ~ NO. 7 holes, II labors place; drill NO.8 ~ NO.10 hole, III labors); Bore bit diameter: 14.5 mms; Cut dosages: V = (10 ~ 18) m/min, s = (0.18 ~0.2 5mm/r, rotation rate 350 r/min. With high-speed steel drill drill transverse direction hole f16 (IV labor, the place) processes a diameter: 16 mms; Cut dosages vs = (10 ~ 18) m/min; S = (0.18 ~ 0.25) mm/r; Rotation rate 350 r/min Use carbide alloy reamer to expand the reaming 1 ~ 7 number holes (V labor place) on labor place V , expand to ream 7 Kong Shi , adopt to expand the hinge compound cutter, feed amounts choosing according to the reamer , cut speed choose according to the broach , enter and the upper limit should select and use permission value according to minimal diameter of compound cutter upper limit for amounts , cutting speed be that the maximum diameter selects and uses permission value according to compound cutter. Process a diameter: 14.5 mm; Cut dosages: V = (8 ~ 10) m/min , ses = 0.25 mm/r , rotation rate 280 r/min; Reamer cutter arbor and nominal guiding part diameter d + 0.08; Reamer common difference: -0.036; Cutter arbor guiding part common difference: -0.006 ~- 0.0017; Lead the cover inside diameter common difference: + 0.024 ~ 0.006. The hole processing procedure room margin in common use reaming is 10 ~ 20, the upper diameter working procedure margin is (1.5 ~ 2.0) mm; provides the reaming diameter to 10 ~20 ;diameter room margin is (0.10 ~ 0.20 ) mm . (all the reference offered by Dong Feng Automobile Co. equipment manufactory design section. 3 The component selection and usage Choosing power standard The driving force component has been used to realize the rotation and the moving forward of the cutting tooling. This machine tool has come true cutting tooling rotation and moving forward. Each driving force head has certain power range according to the cut power and the need of the moving forward power calculated to improve the possibility of the cut dosage, choose the appreciate drive force head, the formula as follows: N moves> (N eager + N of N entering)/ hkW. Among it: N moves is driving force head electric motor power; N eager is cut power , the force and power already have been calculated according to each tooling’s cut dosages from "the conbination machine tool cut force and power calculation formula "; N entering is feed power , which is feed power consumed by oil pump for hydraulic pressure driving force, being (0.8 ~ 2) kW in general; H is drive efficiency , the ding-dang main spindle box is less than 15 time , h = 0.7, more than 15 time , h = 0.65. Machine tool actual power This upright combination machine tool retinue is allotted two electric motors drive many two axle boxes to carry out treating. To many axle boxes of half parts of left cutter, in the hole processing NO.1 ~ NO.7 and the III labor place processes 10 Kong Shi Qi power sum as well as: N/kW = 0.29 X 7 + 0.283 = 2.313 Left main spindle box is less than 15 follows the bore bit , so H = 0.7, N/kW = 2.313/0.7 = 3.3 To many axle boxes of half parts of right cutter, the labor V, the place expands hinge NO.1 ~ NO.7 holes and the actual power attacking silk , the bore bit actual power: N/kW = 0.1427 X 7 = 1.0 Right main spindle box less than 15 bore bits, so H = 0.7, N/kW = 1 / 0.7 = 1.43 Select and use an electric motor since this machine tool has no special requirement in the field of drive, select and use the average ,also the most reliable Y series electric motor, which is close self dyadic cold fan mouse cage type three-phase asynchronization electric motor , substitutesing the J02 series renovation and upgrade product. The left half part required power is 3.3 kW. Check the Y series three-phase asynchronization electric motor form and select and use the Y112M26 type electric motor. Fixed power is 5.5 kW . It is appreciate to select and use this type electric motor. The right half part right required power is 1.43 kW. Check the Y series three-phase asynchronization electric motor form and select and use the Y112M26 type electric motor. Fixed power is 2.2 kW. It is appreciate to select and use this type electric motor. 4 Clamp design The axle bearing seat drills constituting machine tool clamp analysis According to different conditions of the workpiece, there have various installation methods: a) look for installation method; b) the clamp installation way. The basic fixing position principle analyses：among the 6 o'clock fixes position discussed here and 6 liberty degree eliminating find out a righter allocation clamp scheme. A object can have independent 6 motion in space, which is moving along X , Y , Z-axis and separately use X1 , Y1 , Z1 to stand for ; Rotating round X , Y , Z-axis, write down for X2 , Y2 , Z2 . The 6 self-movement are called 6 liberty degree usually. If adopt certain constraint measure to remove the 6 liberty degree of the object, the object’s position will be fixed completely. Take a rectangular parallelepiped as an example, arrange 3 constraint point not on the same line in the basal plane , arrange 2 constraint point in the side , arrange a constraint point on the top face and the basal plane constraint point can restrict the three free degree X2 , Y2 , Z2. Side constraint point restricts two free degree X1 , Z1. This liberty degree on the top face restricts Y1, thus liberty 6 spends with regard to are restricted .That "two key elements " , direction and effects count the fastening motion force clamps force direction should be on the direction of the location component, making required fastening motion strenuously minimal together. Make sure that the location of clamping the force effect point should not destroy allocation. The location of clamping the force effect point should be close the process location as much as possible in order to diminish cutting a force go round the force moment clamping the force effect point to prevent workpiece from coming into being in the process of treating rotating or shake. We should ensure that fastening motion deformation does not affect process accuracy. The number of clamp force effect point should make workpiece accept a force homogeneously on entire contact surface , contact deformation smaller. Ascertain fix position clamping scheme This part belongs to hollow circular casting , the same allocation component has the V shape piece , the thimble fixing position assumes arch allocation, if selecting and using V shape piece allocation, liberty degree moving and winding X , Y axis revolution in Z-axis direction already eliminates, go round the liberty degree that Z-axis turns but have no way to eliminate, therefore using the localized V shape piece scheme is impractical during the period of the bore bit carries out treating. Whose bears fruit and uses V shape piece to be the same if making use of an arch to fix position,having no way to make workpiece stabilize on the direction going round Z-axis , decide to make use of the thimble fixing position to fix position finally. After annularity thimble excessiveness with H7/K6 or H7/js6 puts a thimble inside in coordination with putting the clamp , the part in, method removing , adopt pressure board at the same time in X , Y direction liberty degree; Make use of the ball head bolt to make pressure board hold the workpiece body down tightly. Under here pressure board effect, along zeta-axis revolution X2,and, along Z-axis revolution Z2 and along Z-axis direction Z1, liberty degree is all restricted. X1 , Y1 , Z1 , liberty degree such as X1 , Y1 are removed completely, but under pressure board pressure effect therefore under the effect copying a clamp here,between the part and the cutter friction big and powerful, in the process of treating axial force mutuality is counteracted and , the liberty degree in Z is also removed. Should carry out Kong Shi who processes transverse direction to labor place , IV, X1 , Y1 , Z1 liberty degree have already been removed , X2 , Y2 direction liberty degree have been removed also already , the liberty degree in Z2 direction has also been eliminated on Z2 direction, since controlling the unnatural effect uses workpiece. 5 Chasing bar Attack on combination machine tool when making thread, the part processes location distribution condition and technological requirements etc. , tapping in common use method has 3 kinds according to being processed: Adopt tapping driving force head tapping , adopt chasing bar tapping and adopt the tapping exercising tapping form board. Labor place treating designing that middle , half parts of right are completed V , VI here. The electric motor selects and uses chasing bar tapping only when 5.5 kW power , reasons think synthetically. Some side be used to be completed when attacking silk working procedure , broad all fields pawning entire platform machine tool or machine tool have adopt a chasing bar. The chasing bar is composed of tapping main spindle box and the tapping explorator head , is keeps certain relation, and is sets up since the explorator nut and the explorator pole are go through a grinding to match inkstone's together, to have pitch of screw error to compensate organization. The tapping making use of a chasing bar to be in progress therefore can reach higher accuracy. 6 Constitute the machine tool cooling devise Cooling liquid gets rid of a machine tool besides playing cooling role to the cutter and workpiece , can get up in the film forming lubrication metal outside, to lubrication action. Contain sodium carbonate in a little cooling liquid, nitrous acid sodium waits for a slushing compound, their effect forming the colloidal adsorption film or oxide film , being able to make metal avert corrosion in the metal outside. Come when choosing cooling liquid as a result, to decide the material should accomplish handicraft , job operation , cutter material and the part being processed according to combination machine tool. When processing iron casting, oneself lubricates since casting iron containing black lead per se being able to, do not add cooling liquid in general. Cooling system sometimes flying upward , also increasing by in duplicate work for cutting down iron pink in processing, to improve handling condition. May adopt the mineral , 5%'s emulsion sometimes, whose emulsifier staple can be that the oxide ointment or vulcanization cuts oil. Whose formula is: Ointment 2% ~ 5%, rough process takes low value , finish machining takes good value; Nitrous acid sodium 0.2% ~ 0.25%; Anhydrous sodium carbonate 0.2% ~ 0.3%. Adopt lubricating liquid, to improve surface smoothness then when attacking silk on cast iron workpiece,consumption cutting down power. Adopt a kerosene generally , also, may adopt vulcanization to cut liquid and blending oil and so on. Concrete condition such as responding to the form , diameter size , job operation according to the cutter , cutting dosages ascertains the cooling liquid rate of flow , the design usage experience constituting a machine tool indicates, a kind of cutter , every average cutter cooling liquid rate of flow is (2 ~ 6) L/min about to the crescent-shaped knife with long handle knife , bore bit and milling cutter. Data recommendation chooses abroad according to processing a diameter, each the cutter cooling liquid rate of flow. 7 The job cycle is explained One constituting machine tool , the person job cycle often is comparatively complicated, not only have several driving force head to carry out a job according to different circulation, and these circulation needs coordinating action other if the component, moving the working table , rotary table and drum wheel etc.Every driving force component is drawn support from according to the job stipulating that order is in progress controlling gear iron by program. Otherwise the job cycle is proper as far as possible simplicity moreover gating element ought to few, the machine tool cost of manufacture enlarges, the meeting also reduces the safe function. Originally, the combination machine tool is fit to be put into use in mass production , the efficacy improves greatly. For cost reduction, should select and use the compound cutter much , try one's best to achieve once takin