【正文】 m nothing if not that! In his text he expounds on the idea that one must give their life a purpose. And that is the true topic of this entry. These last four years have been so easy: teach for a grand total of six hours a week, and the rest of my time is mine. Since I39。s cultural foray overseas, has been widely panned by its home audience. Retitled Empresses in the Palace, the American version has been shortened from its original 76 episodes at 45 minutes each, to six 90minute episodes. The quick pacing threw off many native viewers, who are accustomed to a more leisurely daytimesoapstyle narrative rhythm. (Chinese TV stations would run two or three episodes every day.) I did not finish the fulllength version and found the truncated one not difficult to follow. What39。t help but sing the folk songs, Nasun says. The vastness of Inner Mongolia and the lack of entertainment options for people living there, made their lives lonely. The nomadic people were very excited about our visits, Nasun recalls. We didn39。幾個月的時間里，從課題的選定、資料的收集、方案的擬定、課題的具體設(shè)計到論文的審定改進(jìn)，XX 都給與了極大的幫助，傾注了大量的心血。蝸輪蝸桿的設(shè)計時，除了要計算齒受力情況外，還要校核蝸桿的彎曲強(qiáng)度。在文章的最后簡明的介紹了做本次畢業(yè)設(shè)計的一些心得體會。而轉(zhuǎn)臺式多工位鉆、攻自動設(shè)備的設(shè)計中，多工位準(zhǔn)停式轉(zhuǎn)臺和鉆、攻夾具的設(shè)計為主要內(nèi)容。傳動系統(tǒng)受力、彎矩、轉(zhuǎn)矩要發(fā)生變形，變形過大就會影響零件的正常工作，影響轉(zhuǎn)臺的最終測試結(jié)果。按第三強(qiáng)度理論，計算應(yīng)力 224()()caMTW????? W=4288 ? 2524(.61)(.783).caMP??????因選此輸出軸材料為 40Cr 鋼，調(diào)質(zhì)處理，由查文獻(xiàn)[2]查得 ??170MPa???，因此??1ca???，故安全。??用彎曲應(yīng)力計算法校核。?39。蝸輪三維意圖如圖 33 所示。這時 =，從圖 1118 中可查得接觸系數(shù) ，因?yàn)?，1d1d 39。 按齒面接觸疲勞強(qiáng)度進(jìn)行設(shè)計根據(jù)閉式蝸桿傳動設(shè)計準(zhǔn)則查文獻(xiàn)[2]，先按齒機(jī)接觸疲勞強(qiáng)度進(jìn)行計算，3再校核齒根彎曲疲勞強(qiáng)度，由式（35）傳動中心距 （35 ）??232EHZaKT?????????（1）確定作用在蝸輪上的轉(zhuǎn)矩 2按 =1，估取效率 =；1Z? r/???電電 21390/??蝸22..6m?電（2）確定載荷系數(shù)Ｋ　　 因工作載荷較穩(wěn)定，幫取載荷系數(shù) =1，由查文獻(xiàn)[2]選取使用系數(shù)K?=；由于轉(zhuǎn)速不高，沖擊不大，可取動載荷 =；則AK v。=所以 (32)3563Pw???總電 機(jī)上式中 P ——轉(zhuǎn)臺有效功率； ——轉(zhuǎn)臺總效率。4 本章小結(jié)為了達(dá)到高精度轉(zhuǎn)臺的目的，可以有很多方法來實(shí)現(xiàn)。帶傳動(皮帶傳動) 特點(diǎn)(優(yōu)點(diǎn)和缺點(diǎn)): ①結(jié)構(gòu)簡單,適用于兩軸中心距較大的傳動場合；②傳動平穩(wěn)無噪聲,能緩沖、吸振；③過載時帶將會在帶輪上打滑,可防止薄弱零部件損壞,起到安全保護(hù)作用；④是鑄鐵等。從而完成轉(zhuǎn)臺的傳動系統(tǒng)設(shè)計。要求整個過程按照順序有序進(jìn)行。隨著國內(nèi)材料、電子、芯片產(chǎn)業(yè)的不斷發(fā)展，轉(zhuǎn)臺賴以發(fā)展的工業(yè)基礎(chǔ)不斷增強(qiáng)，只要投入足夠的研發(fā)力量，我們必將趕上國際先進(jìn)水平。德國申克公司的 UPM 液壓萬能轉(zhuǎn)臺控制原理是由速度控制器控制力矩電機(jī)進(jìn)而帶動壓力控制閥施加負(fù)荷，并具有速度和電流反饋，保證加荷速度，轉(zhuǎn)臺還具有計算機(jī)數(shù)據(jù)處理和控制功能，是一種傳統(tǒng)的控制方式。在當(dāng)今新技術(shù)革命的浪潮中，轉(zhuǎn)臺行業(yè)正在擺脫傳統(tǒng)產(chǎn)品范疇而迅速向高新技術(shù)產(chǎn)業(yè)發(fā)展。2 加工轉(zhuǎn)臺的國內(nèi)外現(xiàn)狀 國內(nèi)加工轉(zhuǎn)臺的技術(shù)狀況我國從六十年代開始研制萬能轉(zhuǎn)臺，最初時長春轉(zhuǎn)臺研究所研制的定型產(chǎn)品WD 系統(tǒng)，先后移植給寧夏青山轉(zhuǎn)臺廠、廣州轉(zhuǎn)臺廠，目前國內(nèi)市場生產(chǎn)電子萬能轉(zhuǎn)臺廠家比較多，主要有濟(jì)南轉(zhuǎn)臺廠生產(chǎn)的 WDW, WDS 系列，長春轉(zhuǎn)臺研究所生產(chǎn)的 CSS1100C, CSS2200 系列，寧夏青山轉(zhuǎn)臺廠、廣州試驗(yàn)儀器廠生產(chǎn)的WD 系列，長春市第二轉(zhuǎn)臺廠生產(chǎn)的 CMT5000 系列等。圖11 C字夾產(chǎn)品圖設(shè)計一臺兩回轉(zhuǎn)坐標(biāo)數(shù)控轉(zhuǎn)臺(由分度圓工作臺、擺角體、擺角體支架組成)，安裝在三直線坐標(biāo)數(shù)控銑床或加工中心工作臺上，可實(shí)現(xiàn)五軸聯(lián)動加工，如圖l所示。加工轉(zhuǎn)臺的傳動部分主要由蝸輪蝸桿、錐齒輪、主軸三部分組成。而且一次只能加工一個孔。這樣，不僅影響加工精度，而且加工效率低，勞動強(qiáng)度也大。經(jīng)過校核后所有設(shè)計均符合要求。然而傳統(tǒng)的五軸數(shù)控機(jī)床的兩回轉(zhuǎn)坐標(biāo)與機(jī)床滑板制作成一體，這對于用三直線坐標(biāo)加工的絕大多數(shù)場合來說，兩回轉(zhuǎn)坐標(biāo)傳動機(jī)構(gòu)，盡管鎖緊不動，長時歇置，造成浪費(fèi)，并且它的剛性往往遠(yuǎn)不如直線坐標(biāo)，影響機(jī)床加工精度、強(qiáng)力高效加工等。隨著計算機(jī)技術(shù)的飛速發(fā)展，力學(xué)性能的自動測試己成為體現(xiàn)測試技術(shù)現(xiàn)代化的重要標(biāo)志。這不僅因其本身與信息、能源和新材料等領(lǐng)域有著密切的關(guān)系，而更重要的是它能夠直接為眾多的高新技術(shù)領(lǐng)域及產(chǎn)業(yè)提供必不可少的測試設(shè)備。日本島津制作所生產(chǎn)的 UDH 系列液壓萬能轉(zhuǎn)臺其采用自行設(shè)計的電液伺服閥組件控制柱塞缸，可自動和手動兩種操作，具有計算機(jī)控制4和數(shù)據(jù)處理功能，其系列性能好，機(jī)種覆蓋廣，缺點(diǎn)是自動化程度低。 本次設(shè)計主要內(nèi)容在C字夾的制作過程中，C字夾螺孔的加工作為主要工藝內(nèi)容，一般均在兩臺不同的鉆床上進(jìn)行加工，要裝、卸兩次。繪制四工位準(zhǔn)停轉(zhuǎn)臺總裝圖、C字夾鉆、攻夾具總裝圖。如圖 22 所示。渦輪蝸桿傳動最主要的特點(diǎn)就是具有反向自鎖的功能，而且相比其它傳動具有較大的速比，渦輪蝸桿的輸入、輸出軸不在同一軸線上，甚至不在同一個平面上。這次設(shè)計只考慮了三種方案，仔細(xì)對比三個方案，最后選定方案一為本次設(shè)計最終方案?？偛殚單墨I(xiàn)[1]結(jié)合實(shí)際情況選擇合適型號為 Y8014，它的額定功率為 、滿載轉(zhuǎn)速為 1390r/min。??（3）確定彈性影響系數(shù) EZ 因選用青銅蝸輪與鋼蝸桿配對，所以 。?39。1gr??圖 33 蝸輪三維示意圖 校核齒根彎曲疲勞強(qiáng)度 （36）??????? 當(dāng)量齒數(shù) ????22 3339。4238?rctf?vsv ???????查文獻(xiàn)[2]用插值法查得 =、 = 代入式中得vfv? ??? 大于原估計值 ，因此符合設(shè)計要求。轉(zhuǎn)矩 6622 Nn????A圓周力 278431tFNd?軸向力 126750atT??徑向力 ??22nsi31083cos()co(2).95rt ntnnFFaNa?????2 計算支承受力 水平面反力 2106TNHF12 垂直面反力 213697014NVFN??????3 計算彎矩水平面最大彎矩 9864HMm?A垂直面最大彎矩 153VN合成彎矩最大值 ??A4 計算軸的轉(zhuǎn)矩 軸受轉(zhuǎn)矩 2843TN?5 校核軸的強(qiáng)度 針對某些危險截面（即彎矩和扭矩大而軸徑可能不足的截面）做彎扭合成強(qiáng)度校核計算。該軸的三維示意圖如圖 39。所以要對它們進(jìn)行強(qiáng)度、剛度校核，通過校核，所使用的傳動系統(tǒng)均符合要求。本文首先概述了加工轉(zhuǎn)臺的基本定義與國內(nèi)外一些重要生產(chǎn)商的成果。在這次設(shè)計中，查閱了關(guān)于轉(zhuǎn)臺的一些書刊資料，對轉(zhuǎn)臺有了基本的認(rèn)識。由于絲杠的轉(zhuǎn)速很低，故采用了錐齒輪傳動。通過這次的畢業(yè)設(shè)計，學(xué)生不僅開拓了思路、擴(kuò)大了視野、豐富了知識面，還初步掌握了處理具體實(shí)踐問題的科學(xué)方法，為學(xué)生今后發(fā)展打下了堅實(shí)的基礎(chǔ)。t have a formal stage. The audience just sat on the grass. Usually, the performances became a big party with local people joining in. For him, the rewarding part about touring isn39。s lost, I believe, are the interesting setups and pauses that illuminate the Chinese art of 譯文與原文4storytelling. Much of the plot is still there. It is the flavor that was sacrificed. The American edition uses the framework of the Empress Dowager in her senior years reminiscing at the beginning and the end of each episode, hinting at what39。ve been here I have been tasked with nothing more challenging than learning my students39。s essay affects me very deeply. Not as an urging to bee self reliant – I39。s Liaoning province, decades ago. The solider gave the old man a handmade saddle when they bid farewell. The story inspired Nasun to write Carved Saddle, a song that later became one of his most popular numbers. Now, every year, Nasun recruits young singers and dancers for the troupe. The troupe has also designed a new repertoire, which is mostly based on the daily lives of Mongolian people, especially the lives of nomadic families, and has bined contemporary musical elements with folk songs of the region. Haimu, a 25yearold khoomei (a local variant of overtone singing) singer, joined the troupe three years ago. Along with a sixmember band, he performs fast songs and soft ones that he writes－all while playing the horsehead fiddle.Although I learned the piano since childhood and grew up listening to various kinds of music, to me, the folk music of Inner Mongolia is the root, he says. Performing in remote villages is pleasant. I