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湖 南 科 技 大 學
英文文獻翻譯
學 生 姓 名:
學 院: 機電工程學院
專業(yè)及班級: 機械設計制造及其自動化四班
學 號:
指導教師:
2015 年 6 月 6 日
國內(nèi)外帶式輸送機動力學與控制
宋偉剛
摘要:分析國內(nèi)外帶式輸送機動力學的研究進展與方法,進而給出動力學分析的基本方法與過程。
關鍵詞:帶式輸送機;動力學模型;動態(tài)分析
1 .帶式輸送機的設計計算方法與動力學問題
帶式輸送機是當代最重要的散狀物料輸送設備,廣泛地應用于煤炭、鋼鐵、電力、建材等工業(yè)領域,也是港口、料場等物流系統(tǒng)中散料存儲、輸送的重要裝備。
帶式輸送機的設計計算方法的發(fā)展經(jīng)歷了漫長的歷史,作為機械設備的帶式輸送機其設計計算方法和其他機械系統(tǒng)類似地,計算式可以從基本的力學定理、物理學法則所得出。其進展隨著理論研究的深入,計算手段的進步越來越細致與精確。最早可以見到的計算方法是德國HETZL方法,另外,一些公司也提出了較有影響的計算方法,如美國的GOODYEAR公司、GOODRICH公司和日本的阪東橡膠公司等計算方法,這些計算方法的主要阻力計算都屬于概算法。20世紀的50年代,德國的LACHMANN和VIERLING教授提出了精確計算主要阻力中各個分項的計算方法、80年代以后荷蘭的SPAANS教授、美國的CDI公司進一步發(fā)展了精確計算主要阻力中各個分項的計算方法,他們都是從帶式輸送機主要阻力的構成角度得出相應的各個分項。然而精確計算方法當前仍然極少采用,即使在德國標準中。
從功率和張力計算過程看,出現(xiàn)過兩種不同的方法:一種方法是根據(jù)輸送帶垂度條件確定傳動滾筒奔離點張力,再采用逐點張力計算方法計算出傳動滾筒相遇點張力,滾筒上的張力差就是所要求的驅(qū)動功率。早期的蘇聯(lián)計算方法和TD75、DX帶式輸送機設計手冊[7-9]主要是采用此類方法;另一種是直接將各種阻力疊加在一起得出輸送機總的功率需求,進而通過輸送帶和滾筒不打滑條件和垂度限制條件按逐點計算方法計算輸送帶各特征點張力。在當前帶式輸送機設計計算的主導方法德國標準DIN22101-2002和CEMA(第5版)帶式輸送機功率和張力計算方法。DIN22101計算方法屬于上述的第2類、而CEMA計算方法介乎第1和第2類之間,這是由于該方法考慮到運行阻力和張力相關。從上述方法的分析可以看出,計算結果的是否準確的關鍵問題并不取決于計算次序,而在于輸送機運行過程中的阻力計算是否準確。
帶式輸送機的運行過程由啟動-穩(wěn)定運行-停機構成,盡管一條輸送機在絕大部分時間處于穩(wěn)定運行或停機狀態(tài),但是由于在啟動和停機過程會有加速或減速產(chǎn)生慣性載荷,因而在輸送機的設計中需要考慮動載荷的影響。傳統(tǒng)的設計計算方法(如DIN22101)是將輸送機上所有運動部件看成剛性聯(lián)結在一起,同時加速或減速(可以看作“準靜態(tài)”),不考慮輸送帶的粘彈性性質(zhì)以及在啟動、停機過程中驅(qū)動的輸入力(矩)隨時間變化的作用,從而不能給出輸送機在啟動、停機過程的瞬態(tài)過程。從帶式輸送機的瞬態(tài)過程角度來看,在下列幾個方面存在動力學問題:
(1)輸送機的啟動、停機過程的輸送機縱向的速度和應力(張力)的傳播
帶式輸送機(特別是大型帶式輸送機)的結構特點體現(xiàn)在:輸送帶、托輥和物料是散布在輸送線上,輸送帶本質(zhì)上是粘彈性體,因而驅(qū)動裝置的啟動過程是逐漸地將驅(qū)動力和速度傳播到整個輸送帶上,輸送機的啟動是一個漸進的過程,輸送帶的張力由靜止狀態(tài)下的張力變化到穩(wěn)定運行下的張力,張力的變化導致輸送帶的變形量的變化,由拉緊裝置的伸長或縮短和輸送帶的撓度變化所吸收。另一個特點是多驅(qū)動單元與多點驅(qū)動。當沒有考慮到縱向動力學瞬態(tài)過程的影響可能出現(xiàn)的問題包括:
1)選擇過大的驅(qū)動設備的投資費用過高,造成啟動和停機過程中的輸送帶的張力過大;
2)變坡線路的帶式輸送機停機過程中造成輸送帶的局部張力過?。?
3)拉緊裝置的位移設計的不準確,出現(xiàn)拉緊行程不夠或拉緊反應滯后,不能滿足系統(tǒng)的傳動要求;
4)驅(qū)動裝置、制動裝置和拉緊裝置的配置與位置布置不合理;
5)在多驅(qū)動單元系統(tǒng)中啟動或制動過程中由于加載次序與時間控制上的問題產(chǎn)生振蕩,造成各驅(qū)動單元的輸出無法實現(xiàn)同步與功率平衡。
(2)輸送帶在橫截面上的垂直于輸送帶面的振動
輸送帶在張力、載荷和輸送帶固有特性下,當托輥的激振頻率與固有頻率接近或一致時,在輸送帶的橫截面的鉛垂面方向存在振動問題,此振動將會使輸送機機架甚至建筑物發(fā)生破壞[12-14]。
(3)輸送帶在輸送機橫向的跑偏
輸送帶跑偏是廣泛存在的問題,跑偏是引起輸送機停機、撒料、機架堵塞、輸送帶使用期限縮短等后果的主要原因,跑偏的調(diào)整是非常麻煩的事情,從理論上對跑偏分析方法是建立輸送帶橫用運動動力學方程,進而應用穩(wěn)定性理論進行分析。
(4)輸送物料量的變化引起的運行狀態(tài)的變化
輸送物料量的變化會引起運行狀態(tài)的變化,然而這種變化相對于輸送帶的波動周期要長得多,因而一般不會單獨對此問題進行研究,研究的關注點是不同物料載荷分布下的縱向波動問題。
(5)受料過程物料對托輥和輸送帶的沖擊
輸送帶受料處物料沖擊(特別是大塊物料)的沖擊直接危害帶式輸送機的正常使用,是輸送帶損壞的重要原因,導致輸送帶發(fā)生磨損、上覆蓋層、帶芯、甚至是整個輸送帶的擊穿,致使輸送帶的損壞和撕裂,增加托輥的沖擊載荷。
(6)輸送帶經(jīng)過托輥的輸送帶覆蓋層的擠壓變形與恢復輸送帶下覆蓋層在輸送帶的擠壓變形是產(chǎn)生輸送機主要阻力中的壓陷阻力的原因。
從帶式輸送機的控制角度來說,除滿足帶式輸送機滿足工藝要求的順序控制與不同輸送量下的速度改變以及對帶式輸送機的保護控制外,主要的控制要求僅體現(xiàn)在對輸送機瞬態(tài)過程的控制。
從上述的分析可見,帶式輸送機動力學問題涉及帶式輸送機系統(tǒng)的各個方面,本文將重點討論上面所列問題的第(1)方面,而對其他5個方面的問題僅做簡要探討。首先分析國內(nèi)外的研究進展與方法;進而給出動力學分析的基本方法與過程,包括:數(shù)學模型、求解技術、軟件的發(fā)展;典型帶式輸送機系統(tǒng)的動力學分析、動態(tài)分析的作用及其應用范圍等。
動力學研究的主要內(nèi)容與方法:
帶式輸送機的動力學分析與動態(tài)設計方法的研究與應用之所以受到廣泛的關注,是由于隨著帶式輸送機系統(tǒng)的大型化,傳統(tǒng)的半靜態(tài)設計計算方法已經(jīng)不能滿足工程實際應用的需求。另一方面,動態(tài)設計方法的采用有助于提高設計水平,達到提高企業(yè)競爭力。動態(tài)設計與動態(tài)優(yōu)化設計也是面向產(chǎn)品廣義質(zhì)量的綜合設計方法[96]的重要組成部分。因而,帶式輸送機的動力學與動態(tài)設計方法涉及到帶式輸送機的所有方面,即:
1)帶式輸送機各個運動部件的力學性能,特別是輸送帶;
2)輸送機運行阻力的計算方法及其規(guī)律性問題;
3)驅(qū)動、制動、拉緊、傳動裝置的結構與特性以及控制方法;
4)帶式輸送機各運動部件的數(shù)學模型以及由各個部件的數(shù)學模型所構成的整機模型;
5)所建立的動力學模型的求解方法與軟件開發(fā);
6)各種驅(qū)動裝置、制動裝置和拉緊裝置動態(tài)響應對啟制動特性的影響;
7)復雜帶式輸送機系統(tǒng)各種運行工況下動態(tài)行為研究,包括啟動、制動、上運、下運等;
8)各種工況下的現(xiàn)場測試分析,控制系統(tǒng)的動態(tài)調(diào)整。
Dynamics and Control of Belt Conveyor at Home and Abroad
SONG Wei-gang
Abstract: analysis of the belt conveyor dynamics both at home and abroad research progress and the method, and dynamics analysis of the basic method and the process is given.
Key words: belt conveyor; Dynamic model; A dynamic analysis
1. The belt conveyor and the design method of dynamic problems
Belt conveyor is the most important contemporary material conveying equipment, widely used in industrial area, such as coal, steel, power, building material, port, yard logistics system such as releasing the importance of materials storage, transportation and equipment.
The development of the design and calculation method of belt conveyor has experienced a long history, as the belt conveyor design calculation methods of mechanical equipment and other mechanical systems similarly, calculation formula can be from basic mechanics theorem, obtained from the laws of physics. Its progress with the deepening of theoretical research, the calculation method of progress more and more detailed and accurate. Is the earliest can meet the calculation method of German HETZL method, in addition, some companies are put forward and the calculation method of influential companies, such as America's GOODYEAR GOODRICH and Japan e. calculation methods, such as east rubber company, the main resistance calculation of these calculation methods are approximate method. The 50 s of the 20th century, the German professor LACHMANN and VIERLING presented the calculation method of precise calculation of the main resistance of each component, SPAANS professor after the Netherlands in the 80 s, the United States of CDI company in the further development of the precise calculation of the main resistance and the calculation method of each item they are from the Angle of the composition of the main belt conveyor resistance of the various disciplines. Accurate method to calculate the current still rarely used, however, even in the German standa
From the power and tension calculation process, there have been two different methods: a method is based on a conveyor belt sag condition determine the transmission drum ran away from the point of tension, then use point by point tension calculation method to calculate the transmission drum meet some tension, tension difference of the roller is the driving power required. The calculation method of the Soviet union and early TD75, DX belt conveyor design manual [7-9] is mainly adopted such methods; Another kind is the superposition of all kinds of resistance directly together conveyor total power demand, and then through the conveyor belt and roller not skid and sag restriction conditions according to the point by point calculation method to calculate the conveyor belt tension of the feature points. In the current belt conveyor design and calculation the dominant method of Germany and CEMA standard DIN22101-2002 (fifth edition) power belt conveyor, and tension calculation method. DIN22101 calculation method belongs to the second class, and CEMA calculation method between 1 and 2 class, this is due to the method considering the running resistance and tension. Can be seen from the analysis of the above methods, the calculated results are accurate sequence does not depend on the key problems in the calculation, but in the conveyor running resistance in the process of calculation is accurate.
The operation process of belt conveyor consists of start-up - stable operation - stop, although in most of the time in the stable operation of a conveyor or stop state, but the process at the start and stop will have inertia load produced by the acceleration or deceleration, and therefore need to be considered in the design of the conveyor dynamic load. Traditional design and calculation methods (such as DIN22101) are all moving parts on the conveyor as rigid connection together, at the same time accelerate or decelerate (which can be seen as a "quasi static"), regardless of the viscoelastic properties of conveyor belt and drive in the process of start-up, stop input force (torque) change over time, and so cannot be given conveyor in transient process in the process of start-up, stop. From the Angle of the transient process of belt conveyor, the dynamic problems in the following aspects:
(1) the start of the conveyor, stop the conveyor in the process of the longitudinal stress (strain) and the speed of transmission
especially large belt conveyor belt conveyor structure characteristics embodied in: conveyor belt, roller, and material is spread on the transmission line, conveyor belt is essentially a viscoelastic body, thus drive the boot process is gradually will spread to the whole conveyor belt, driving force and speed of the conveyor start is a gradual process, conveyor belt tension by static state changes to stable operation under tension, change of the amount of deformation of the conveyor belt tension, the tension device of elongation or shortening and absorbed by the deflection of conveyer belt change. Another characteristic is more drive unit and multi-points driving. When there is no considering the influence of the longitudinal dynamic transient process possible problems include:
1) choose too driven equipment investment cost is too high, cause in the process of start and stop the conveyer belt tension is too large;
2) changing slope line of the belt conveyor downtime caused the conveyor belt in the process of local tension is too small;
3) displacement of the tension device design is not accurate, appear taut enough or pull tight schedule response lag, cannot satisfy the requirement of the system transmission;
4) drive, brake and tension device configuration and location layout is unreasonable;
5) in a multiple drive unit in the system to start or braking process due to the loading sequence and time control on the oscillation problem, caused by the drive unit of output cannot realize synchronization and power balance.
(2) the conveyor belt on cross section perpendicular to the conveyor belt surface vibration
Intrinsic properties in tension, the load and conveyor belt conveyor belt, when the vibration frequency and inherent frequency of roller close to, or agreement, conveyor belt of the cross section in the direction of the vertical surface vibration problems, the vibration will make the conveyor frame buildings destroyed even [12-14].
(3) the conveyor belt running deviation in horizontal conveyor
Conveyor belt running deviation is widespread problem, running deviation is conveyor downtime, and materials, frame jam, conveyor belt use shortened the main reason for the consequences, such as running wide adjustment is very troublesome, theoretically analyzing the running deviation method is to establish a dynamics equation of movement of the conveyor belt cross use, and application of the theory of stability was analyzed.
(4) conveying material quantity changes caused by changes in the running state
Conveying material quantity change will cause the change of running state, but the change relative to the conveyor belt is much longer, and the volatility of the cycle and generally will not separate study on this question, the research focus is on different materials under the load distribution of longitudinal wave problem.
(5) materials by the process of material on the roller and the impact of the conveyor belt
Conveyor belt is impacted by the material in the material (especially the big materials) impact directly endanger the normal use of belt conveyor, is the important reason for the damage of conveyor belt, conveyor belt leads to wear, covering layer, core, and even the breakdown of the whole conveyor belt, cause the damage of the conveyor belt and tear, increase the impact load of roller.
(6) after a roller conveyor belt conveyor belt cover extrusion deformation and recovery
Conveyor belt under extrusion deformation of cover on the conveyor belt is conveyor main drag in the sag resistance.
From the point of view, the control of belt conveyor in addition to meet the meet the technological requirements of belt conveyor under different throughput sequence control and the speed of change and the protection of a belt conveyor control, the control requirements of main lies only in the conveyor of the transient process control.
Visible from the above analysis, the belt conveyor dynamic problems involved in all aspects of the belt conveyor system, this article focuses on the first (1) aspects of listed above, and the other five aspects of the problem only briefly discussed in this paper. First analysis of the domestic and foreign research progress and the method; , in turn, dynamics analysis is given of the basic method and process, including: the development of mathematical models, solving technology, software; Dynamics analysis of a typical belt conveyor system, function and application scope of dynamic analysis, etc.
The main content and method of dynamics research
Belt conveyor's dynamic analysis and dynamic design method of research and application are widely attention, is because with the large-scale of belt conveyor system, traditional half static design calculation methods have been can't meet the needs of engineering application. On the other hand, the adoption of the dynamic design method is helpful to improve the design level, to improve enterprise competitiveness. Dynamic design and dynamic optimization design is a comprehensive design method of generalized quality oriented products is an important part of the [. Therefore, the dynamics of belt conveyor and dynamic design method involves all aspects of belt conveyor, namely:
1) all the moving parts of belt conveyor mechanical properties, especially the conveyor belt;
2) the calculation method of conveyor running resistance and its regularity problem;
3) driving, braking, taut, the structure and characteristic of transmission device and control method;
4) the mathematical model of the moving parts and belt conveyor consists of mathematical model of the parts of the whole machine model;
5) the established dynamic model of solving method and software development;
6) all kinds of drive, brake and tension device to rev braking characteristics of dynamic response;
7) complex belt conveyor system dynamic behavior under various operating conditions, including starting, braking, on delivery and shipment, etc.;
8) all kinds of conditions of the site test and analysis, dynamic adjustment of the control system.
帶式輸送機傳動裝置設計 21
目 錄
一 緒論………………………………………………………………………1
二 結構設計
三 設計計算過程及說明……………………………………………………….3
1 選擇電動機.......................................................... ....................................….3
2 傳動裝置的總傳動比及其分配.......................................….............................3
3 計算傳動裝置的運動和動力裝置參數(shù)..................................…........................3
4 帶傳動設計.......................................................…..........................................4
5 齒輪傳動設計.....................................................…........................................5
6 軸的設計........................................................................................…...........11
7 軸承的選擇 ..............................................................................................…22
8 鍵的選擇.....................................................….........................................…22
9 減速機箱體的設計...............................................…......................................23
10 減速器附件設計.....................................................................................….23 11密封與潤滑.......................................................…........................................24
四 設計小結……………………………………………………………….……25
五參考文獻………………………………………………….……………………26
1 緒論
通過查閱一些文獻我可以了解到帶式傳動裝置的設計情況,為我所要做的課題確定研究的方向和設計的內(nèi)容。
1.1 帶傳動
帶傳動是機械設備中應用較多的傳動裝置之一,主要有主動輪、從動輪和傳動帶組成。工作時靠帶與帶輪間的摩擦或嚙合實現(xiàn)主、從動輪間運動和動力的傳遞。
帶傳動具有結構簡單、傳動平穩(wěn)、價格低廉、緩沖吸振及過載打滑以保護其他零件的優(yōu)點。
1.2圓錐-圓柱齒輪傳動減速器
YK系列圓錐-圓柱齒輪傳動減速器適用的工作條件:環(huán)境溫度為-40~40度;輸入軸轉(zhuǎn)速不得大于1500r/min,齒輪嚙合線速度不大于25m/s,電機啟動轉(zhuǎn)矩為減速器額定轉(zhuǎn)矩的兩倍。YK系列的特點:采用一級圓弧錐齒輪和一、二、三級圓柱齒輪組合,把錐齒輪作為高速級(四級減速器時作為第二級),以減小錐齒輪的尺寸;齒輪均采用優(yōu)質(zhì)合金鋼滲碳淬火、精加工而成,圓柱齒輪精度達到GB/T10095中的6級,圓錐齒輪精度達到GB/T11365中的7級;
減速器的選用原則:(1)按機械強度確定減速器的規(guī)格。減速器的額定功率P1N 是按載荷平穩(wěn)、每天工作小于等于10h、每小時啟動5次、允許啟動轉(zhuǎn)矩為工作轉(zhuǎn)矩的兩倍、單向運轉(zhuǎn)、單對齒輪的接觸強度安全系數(shù)為1、失效概率小于等于1%等條件算確定.當載荷性質(zhì)不同,每天工作小時數(shù)不同時,應根據(jù)工作機載荷分類按各種系數(shù)進行修正.減速器雙向運轉(zhuǎn)時,需視情況將P1N乘上0.7~1.0的系數(shù),當反向載荷大、換向頻繁、選用的可靠度KR較低時取小值,反之取大值。功率按下式計算:P2m=P2*KA*KS*KR ,其中P2 為工作功率; KA 為使用系數(shù); KS 為啟動系數(shù); KR 為可靠系數(shù)。(2)熱功率效核.減速器的許用熱功率PG適用于環(huán)境溫度20℃,每小時100%連續(xù)運轉(zhuǎn)和功率利用律(指P2/P1N×100%)為100%的情況,不符合上述情況時,應進行修正。(3)校核軸伸部位承受的徑向載荷。
2結構設計
2.1V帶傳動
帶傳動設計時,應檢查帶輪的尺寸與其相關零部件尺寸是否協(xié)調(diào)。例如對于安裝在減速器或電動機軸上的帶輪外徑應與減速器、電動機中心高相協(xié)調(diào),避免與機座或其它零、部件發(fā)生碰撞。
2.2減速器內(nèi)部的傳動零件
減速器外部傳動件設計完成后,可進行減速器內(nèi)部傳動零件的設計計算。
1) 齒輪材料的選擇應與齒坯尺寸及齒坯的制造方法協(xié)調(diào)。如齒坯直徑較大需用鑄造毛坯時,應選鑄剛或鑄鐵材料。各級大、小齒輪應該可能減少材料品種。
2) 蝸輪材料的選者與相對滑動速度有關。因此,設計時可按初估的滑速度選擇材料。在傳動尺寸確定后,校核起滑動速度是否在初估值的范圍內(nèi),檢查所選材料是否合適。
3) 傳動件的尺寸和參數(shù)取值要正確、合理。齒輪和蝸輪的模數(shù)必須符合標準。圓柱齒輪和蝸桿傳動的中心距應盡量圓整。對斜齒輪圓柱齒輪傳動還可通過改變螺旋角的大小來進行調(diào)整。
根據(jù)設計計算結果,將傳動零件的有關數(shù)據(jù)和尺寸整理列表,并畫出其結構簡圖,以備在裝配圖設計和軸、軸承、鍵聯(lián)結等校核計算時應用。
聯(lián)軸器的選擇
減速器的類型應該根據(jù)工作要求選定。聯(lián)接電動機軸與減速器,由于軸的轉(zhuǎn)速高,一般應選用具有緩沖、吸振作用的彈性聯(lián)軸器,例如彈性套柱銷聯(lián)軸器、彈性柱銷聯(lián)軸器。減速器低速軸(輸出軸)與工作機軸聯(lián)接用的連周期,由于軸的轉(zhuǎn)速較低,傳遞的轉(zhuǎn)距較大,又因為減速器軸與工作機軸之間往往有較大的軸線偏移,因此常選用剛性可以移動聯(lián)軸器,例如滾子鏈聯(lián)軸器、齒式聯(lián)軸器。
聯(lián)軸器型號按計算轉(zhuǎn)距進行選擇。所選定的聯(lián)軸器,起軸孔直徑的范圍應與被聯(lián)接兩軸的直徑相適應。應注意減速器高速軸外伸段軸徑與電動機的軸徑不得相差很大,否則難以選擇合適的聯(lián)軸器。
3 設計計算過程及說明
3.1選擇電動機
3.1.1電動機類型和結構型式選擇
Y系列籠型三相異步電動機,臥式閉型電電動機。
3.1.2選擇電動機容量
工作機所需功率
==7.98kw
=80.7r/min
電動機的輸出功率
==10.4kw
η=*…..* =0.82*0.98*0.95*0.98*0.97*0.98*0.98*0.97*0.98*0.98*0.99*0.96=0.77
確定電動機的額定功率
Ped>=Pd
3.1.3選擇電動機的轉(zhuǎn)速
同步轉(zhuǎn)速 1500r/min。
3.1.4確定電動機型號
選擇 Y160M-4 額定功率 11kw 轉(zhuǎn)速 1460r/min
3.3計算傳動裝置的運動和動力裝置參數(shù)
各軸轉(zhuǎn)速: 電動機軸 =1460r/min
減速箱輸入軸 ==486.7 r/min
高速軸 ==235.1 r/min
低速軸 ==58.8 r/min
各軸輸入功率: ==11kw
=*0.95=10.45kw
=*0.98*0.97*0.98=9.73KW
=*0.98*0.97*0.98=9.07KW
3.4帶傳動設計
3.4.1定v帶型號和帶輪直徑
工作情況系數(shù) =1.1
計算功率 ==1.1*11=12.1kw
選帶型號 A型
3.4.2計算帶長
求 = (+)/2 =198.5mm
求Δ Δ=(-)/2=98.5mm
2(+)>=a>=0.7*(+)
初取中心距 a=600mm
帶長 L=πDm+2*a+=1839.5
基準長度 =2000mm
求中心距和包角
中心距 a= + =344.18+337.06=681.24<700mm
小輪包角 α1=180°-(D2-D1)*60°=180°-(297-100)*60°/681.24 =162.6>120°
z=/((+Δ)**)=12.1/((1.32+0.17)*0.95*1.03)=8.3 取9根
求軸上載荷
張緊力 =500*/v*z(2.5-)/+qv*v=500*12.1/(7.64*9)*(2.5-0.95)/0.95+0.10*=149.3N
軸上載荷 =2*sin(/2)=2*9*149.3*sin(162.6°/2)=2656.5N
3.5齒輪傳動設計
直齒錐齒: 軸交角∑=90° 傳遞功率P=10.45kw
小齒輪轉(zhuǎn)速=486.7r/m 傳動比i=2.07
載荷平穩(wěn),直齒為刨齒,小齒輪40Cr,調(diào)質(zhì)處理,241HB~~286HB
平均260HB,大齒輪用45號鋼,217HB~~255HB 平均230HB
齒面接觸疲勞強度計算
齒數(shù)和精度等級 取=24 =i*=48
選八級精度
使用系數(shù)=1.0 動載荷系數(shù)=1.15
齒間載荷分配系數(shù) 估計*Ft/b<100N/mm
cos=u/=2/=0.89
cos=1/=1/=0.44
=/ cos=24/0.89=26.97
=/ cos=48/0.44=109.1
αv=(1.88-3.2(1/(2*)+1/(2*)))cos=1.85
==0.85
==1.4
齒向載荷分布函數(shù) =1.9
載荷系數(shù) ==1*1.5*1.4*1.9=3.99
=680Mpa
接觸最小安全系數(shù)=1.5
接觸壽命系數(shù) ==1.0
許用接觸應力 []= */=710*/1.05=676Mpa
[]= */=680*/1.05=648Mpa
小輪大端分度圓直徑 =0.3
=70mm
驗算圓周速度及Ka*Ft/b
=(1-0.5R) =(1-0.5R)70=59.5mm
==3.1459.5*486.7/60000=1.5m/s
=
b=*R=*d/(2*sin)=*/(2*=20.4mm
*/b=1.0*689.2/20.4=33.8N/mm<100N/mm
確定傳動尺寸
大端模數(shù) m=/=70/24=2.9mm
實際大端分度圓直徑d =m=3*24=84
=m=3*48=144
b=*R=0.3*80.5=24.15mm
齒根彎曲疲勞強度計算
齒面系數(shù) =2.72 =2.38
應力修正系數(shù) =1.66 =1.78
重合度系數(shù) =0.25+0.75/ =0.25+0.75/0.85=0.66
齒間載荷分配系數(shù) */b<100N/mm
=1/=1/0.66=1.56
載荷系數(shù) ==1*1.15*1.56*1.9=3.4
許用彎曲應力 []= lim/=600*1.0*1.0/1.25=480MPa
[]=570*1.0*1.0/1.25=456MPa
驗算
===152
<[]
==152*2.38*1.78/(2.72*1.66)=142.6MPa
值 取=85
初步計算的許用接觸應力[H1]=0.96Hlim1=0.9*710=619MPa
[H2]=0.9Hlim2=1.9*580=522MPa
初步計算的小齒輪直徑 =Ad=85*=48.1mm
齒數(shù)z和模數(shù)m 初步齒數(shù)=19; =i*19=4*19=76
和螺旋角 =/=50/19=2.63158
=2.5mm
=arcos=arccos2.5/2.63158=18.2°
使用系數(shù) =1.10
動載系數(shù) =1.5
齒間載荷分配系數(shù)
= arctan=arctan=20.9°
cos =cos18.2°20cos°/20.9cos°=0.95
齒向載荷分布系數(shù) =A+B[1+0.6*]+c*b/1000=1.36
=** * =1.10*1.05*1.76*1.36=2.76
彈性系數(shù) =189.8
許用接觸應力
驗算
=189.8*2.38*0.97=647MPa<690MPa
齒根彎曲疲勞強度驗算
重合度系數(shù)
=1.61
螺旋角系數(shù)
齒向載荷分配系數(shù)
=1.76<
齒向載荷分布系數(shù) b/h=50.(2.25*2.5)=8.9
=1.27
載荷系數(shù) K=**
許用彎曲應力
驗算
3.6軸的設計
輸入軸
選用45鋼調(diào)質(zhì)
=tan
=
計算支反力
水平面反力 =1102.7N
=-413.5N
垂直面反力 =-1235.7N
=4115.5N
許用應力
許用應力值
應力校正系數(shù)
當量彎矩圖
軸徑
高速軸
軸材料選用45鋼調(diào)質(zhì),
取 d=40mm
計算螺旋角
齒輪直徑 小輪 =
大輪
小齒輪受力 轉(zhuǎn)矩=9.55*
圓周力 =2*/=2*39524/50=1581N
徑向力
畫小齒輪軸受力圖
水平反力 =1358.1N
=912.1N
垂直反力 =594.7N
=103.3N
水平受力圖
水平彎矩圖
垂直彎矩圖
合成彎矩圖
畫轉(zhuǎn)矩圖
應力校正系數(shù)
畫當量彎矩圖
=50220N.mm
校核軸徑 =20.3<40mm
低速軸
材料同前兩軸
畫大齒輪受力圖
計算支反力
水平反力 =1185.8 =395.2N
垂直反力 =21.2N =584.6N
垂直受力圖
水平彎矩圖
垂直彎矩圖
合成彎矩圖
轉(zhuǎn)矩圖
當量彎矩
校核軸徑
=26<60mm
3.7軸承的選擇
輸入軸軸承選擇:
選用圓錐滾子軸承30208 e=0.37 Y=1.6 Cr=63000N
=1177.7N
=4297.0N
=/(2*Y)=368N
=/(2*Y)=1342.8N
=1228.4N =1342.8N
/=1.0>e /=0.3
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