【正文】 零件的尺寸設(shè)計(jì)及校核；利用學(xué)過的知識(shí)綜合考慮，通過對(duì)比的方法確定出最合理、簡(jiǎn)單、經(jīng)濟(jì)的方案，各傳動(dòng)零件的材料、尺寸的確定及強(qiáng)度校核。4．合理分配傳動(dòng)比運(yùn)動(dòng)鏈的傳動(dòng)比應(yīng)合理分配給各級(jí)傳動(dòng)機(jī)構(gòu)，具體分配方法應(yīng)注意兩點(diǎn)：1）每一級(jí)的傳動(dòng)應(yīng)在常用的范圍之內(nèi)選取。圖 21 對(duì)稱斷面的形狀因子與成型道次擬定的驅(qū)動(dòng)方案①鏈驅(qū)動(dòng)：若用一條鏈驅(qū)動(dòng)所有上下軸，軸的調(diào)節(jié)量就很小，速度會(huì)受到限制，改變鏈的驅(qū)動(dòng)會(huì)有比較大的上軸垂直調(diào)節(jié)能力。然而，下軸驅(qū)動(dòng)軋輥，板料間的摩擦力僅為雙軸驅(qū)動(dòng)摩擦力的一半。通電導(dǎo)線在磁場(chǎng)中受力運(yùn)動(dòng)的方向跟電流方向和磁感線（磁場(chǎng)方向）方向有關(guān)。它使用方便 、運(yùn)行可靠 、價(jià)格低廉 、結(jié)構(gòu)牢固，但功率因子較低，調(diào)速也較困難。電動(dòng)機(jī)運(yùn)行時(shí)需注意使其負(fù)載的特性與電機(jī)的特性相匹配，避免出現(xiàn)飛車或停轉(zhuǎn)。P==.85kw2P= 361458 31? (注： 為通過鏈與電機(jī)連接的軸， ， ， ， ， ， 為軋輥下軸)0p1p234p56洛陽理工學(xué)院畢業(yè)設(shè)計(jì)（論文）12 確定各軸轉(zhuǎn)速設(shè)與電機(jī)連接的鏈輪的傳動(dòng)比為 =6，功率為 的軸上的鏈輪與第一道軋輥0i0P下軸的傳動(dòng)比為 ，第一道軋輥下軸與第二道軋輥下軸的傳動(dòng)比 ，第二道1i=3 2i=1軋輥下軸與第三道軋輥下軸傳動(dòng)比是 ，第三與道軋輥下軸第四道軋輥下軸傳3i=1動(dòng)比為 ，第四道軋輥下軸與第五道軋輥下軸傳動(dòng)比為 ，第六道軋輥下軸4i 5i與第五道下軸傳動(dòng)比為 。良好的軋輥材料體現(xiàn)在兩個(gè)方面：，保證其合理性。本設(shè)計(jì)基于以上條件的要求，結(jié)合實(shí)際情況。設(shè)上輥的寬度取 120mm,下輥寬度取 160，賦予⑧的值為 300mm；如圖 46①= = ②=圖 46 第二道次軋輥寬度和直徑③=60①== ④=②2 ③ tan42=?⑤= = ⑥=⑦=()/tan42= ⑧=300mm⑨=80⑦⑤== 第三道次尺寸的確定洛陽理工學(xué)院畢業(yè)設(shè)計(jì)（論文）18其(部分對(duì)稱 )斷面圖,如圖 47==2πR+（② ）δ/1(=①+ +（R+t）B/??3tan(/2)?=(R+t) + +③23tan(θ2)δ/①+ +R tan( )1Tδ/R tan( )+ +③2?3/代入數(shù)據(jù)得： = = = =驅(qū)動(dòng)直徑 =。 裝軋輥的軸段長(zhǎng)度50140???高寬長(zhǎng)設(shè)為 300mm。在強(qiáng)度計(jì)算時(shí)常以齒寬中點(diǎn)處的當(dāng)量齒數(shù)作為計(jì)算依據(jù)。表 52 錐齒輪模數(shù)錐齒輪模數(shù)（摘自 GB1236890）… 3 5 6 7 8 …修正小齒輪的齒數(shù)： ， （此處 為根據(jù)接觸強(qiáng)度計(jì)算的值）并取1mz=d/m1d大于該數(shù)的整數(shù)（不四舍五入）作為小齒輪的齒數(shù)，計(jì)算 ， 取整數(shù)。故只需驗(yàn)證第一道軋輥上軸的最小直徑1即可。5dDBmm?????????洛陽理工學(xué)院畢業(yè)設(shè)計(jì)（論文）31處包括起緊固作用的兩塊側(cè)板和角接觸球軸承，根據(jù)實(shí)際需要及設(shè)計(jì)經(jīng)驗(yàn)可設(shè)側(cè)板厚度 =15mm,所以 =B+2 =45+2 15=75mm。PaM60]1??如圖：圖 63 輸入軸的結(jié)構(gòu)洛陽理工學(xué)院畢業(yè)設(shè)計(jì)（論文）34根據(jù)公式求得最小軸徑為 ?處裝輸入小錐齒輪，軸徑選為 46mm,選 =50mm 選鍵 C14 32。2 處裝錐齒輪，選BD2415?? mL431?，選建 A20 40。510?減速器殼體材料選擇 ZL111。，各梁間距 420mm。比如：如何傳動(dòng)才能保證零件較高的精度；材料的選擇是否考慮承載載荷和材料的浪費(fèi)。但在這次畢業(yè)設(shè)計(jì)過程中，遇到了不少困難，碰到了自己難以解決的難題。洛陽理工學(xué)院畢業(yè)設(shè)計(jì)論文39參考文獻(xiàn)[1] 石京，[J].軋鋼，1998：7.[2] [M].北京：高等教育出版社，2022：20～50.[3] 濮良貴，[M].北京：高等教育出版社，2022：165～383.[4] (日 )小奈弘著 ,[M].北京：化學(xué)工業(yè)出版社，2022：1～11.[5] (加 )喬治 哈姆斯著，[M].北京：化學(xué)工業(yè)出?版社，2022：1～4. [6] [M].北京：機(jī)械工業(yè)出版社，2022：38～58.[7] [M].北京：國(guó)防科技大學(xué)出版社，2022：3～10.[8] 史永凌，[J].焊管，2022：2.[9] [M].西安：西安電子科技大學(xué)出版社，2022：39～42.[10] [M].北京：機(jī)械工業(yè)出版社，2022：134～190.[11] 劉建華，[M].北京：電子工業(yè)出版社，2022：34～56.[12] [M].北京：北京理工大學(xué)出版社，1998：34～67.[13] [M].北京：中國(guó)石化出版社，1995：23～25.[14] Ⅰ[M].北京：高等教育出版社，2022：300～350.[15] 陳良玉，[M].東北大學(xué)出版社，2022：139～170.[16] [M].北京：機(jī)械工業(yè)出版社，2022：89～91.洛陽理工學(xué)院畢業(yè)設(shè)計(jì)論文40外文資料翻譯EXTENDING BEARING LIFEAbstract：Nature works hard to destroy bearings, but their chances of survival can be improved by following a few simple guidelines. Extreme neglect in a bearing leads to overheating and possibly seizure or, at worst, an explosion. But even a failed bearing leaves clues as to what went wrong. After a little detective work, action can be taken to avoid a repeat performance. Key words: bearings ；failures ；life Bearings fail for a number of reasons，but the most mon are misapplication，contamination，improper lubricant，shipping or handling damage，and misalignment. The problem is often not difficult to diagnose because a failed bearing usually leaves telltale signs about what went wrong．However，while a postmortem yields good information，it is better to avoid the process altogether by specifying the bearing correctly in The first place．To do this，it is useful to review the manufacturers sizing guidelines and operating characteristics for the selected bearing.Equally critical is a study of requirements for noise, torque, and runout, as well as possible exposure to contaminants, hostile liquids, and temperature extremes. This can provide further clues as to whether a bearing is right for a job.1. Why bearings failAbout 40% of ball bearing failures are caused by contamination from dust, dirt, shavings, and corrosion. Contamination also causes torque and noise problems, and is often the result of improper handling or the application environment．Fortunately, a bearing failure caused by environment or handling contamination is preventable，and a 洛陽理工學(xué)院畢業(yè)設(shè)計(jì)論文41simple visual examination can easily identify the cause．Conducting a postmortem il1ustrates what to look for on a failed or failing bearing．Then，understanding the mechanism behind the failure, such as brinelling or fatigue, helps eliminate the source of the problem.Brinelling is one type of bearing failure easily avoided by proper handing and assembly. It is characterized by indentations in the bearing raceway caused by shock loading－such as when a bearing is droppedor incorrect assembly. Brinelling usually occurs when loads exceed the material yield point(350,000 psi in SAE 52100 chrome steel)．It may also be caused by improper assembly, Which places a load across the races．Raceway dents also produce noise，vibration，and increased torque.A similar defect is a pattern of elliptical dents caused by balls vibrating between raceways while the bearing is not turning．This problem is called false brinelling. It occurs on equipment in transit or that vibrates when not in operation. In addition, debris created by false brinelling acts like an abrasive, further contaminating the bearing. Unlike brinelling, false binelling is often indicated by a reddish color from fretting corrosion in the lubricant.False brinelling is prevented by eliminating vibration sources and keeping the bearing well lubricated. Isolation pads on the equipment or a separate foundation may be required to reduce environmental vibration. Also a light preload on the bearing helps keep the balls and raceway in tight contact. Preloading also helps prevent false brinelling during transit.Seizures can be caused by a lack of internal clearance, improper lubrication, or excessive loading. Before seizing, excessive, friction and heat softens the bearing steel. Overheated bearings often change color，usually to blueblack or straw colored．Friction also causes stress in the retainer，which can break and hasten bearing failure．Premature material fatigue is caused by a high load or exce