【正文】 算 電動機的參數 選用最常見的 Y系列三相異步電動機 (ZBK2202288), 型號： Y90S6，額定功率：,滿載轉速： 910r/min。 確定帶輪的基準直徑 dd1和 dd2 初選小帶輪的基準直徑 dd1 根據 V帶截型，參考表 86及表 88，選取 dd1=63mm 驗算帶的速度 V 根據式（ 813）來計算的速度 V= 將 ,帶入式中，得： V==3m/s 計算從動輪的基準直徑 dd2 確定中心距 a和帶的基準長度 Ld 如果中心距未給出，可根據傳遞的結構需要初定中心距 a0,取 即代入 ,得： 初取 a0確定后，根據帶傳動的幾何關系，按下式計算所需帶的基準長度 (42) 將， ,代入上式中，得： 根據 L’ d由表 82中選取和 L’ d相近的 V帶的基準長度 Ld，取由于 V帶傳動的中心距一般是可以調整的，固可采用下式作近似計算，即 考慮安裝調整和補償預緊力的需要，中心距的變動范圍為： 驗算主動輪上的包角α 1 根據（ 86）及對包角的要求，應保證 10 確定帶的根數 Z (43) 式中： Kα — 考慮包角不同時的影響系數， 簡稱包角系數，查表 85。選取軸的材料 45 鋼，調質處理。而 lⅦ Ⅷ =19mm右端滾動軸承采用軸肩進行軸向定位。兩個齒盤的中間采用軸肩定位，軸肩高度 ,取 h=6mm,則軸環(huán)處的直徑dⅤ Ⅳ =58mm。按 dⅣ Ⅴ 由手冊查得平鍵截面(GB/T10951979)，鍵槽用鍵槽銑刀加工，長為 mm（標注鍵長見 GB/T10961979） ,同時為了保證齒盤與軸配合有良好的對中性，故選擇齒盤與軸的配合為 H7/n6；同樣，從動輪與軸的聯(lián)接，選用平鍵為，從動輪與軸的配合 H7/k6。 零件的強度剛度計算 求軸上的載荷 首先根據軸的結構圖作出軸的計算簡圖。（如圖 5） 從軸的結構圖以及彎矩和扭矩圖中可以看出截面 C是軸的危險截面。mm 總彎矩 扭矩 T=38000N因此故安全。截面 C上雖然應力最大，但應力集中不大（過盈配合及鍵槽引起的重力集中均在兩端），而且這里軸的直徑最大，故截面 C也不必校核。mm 截面上的彎曲應力 軸的材料為 45鋼，調質處理。 31及167。 軸承的校核 查軸承樣本可知， 7209AC軸承的 求出軸承受到徑向載荷 R1和 R2 求軸承的計算軸向力 A1和 A2 對于 7209AC軸承按表 137， 軸承內部附加軸向力 ,其中 e為表 135中的判斷系數，其值由的大小來確定，但現(xiàn)在軸承軸向力 A未知，故設取 e=，因此可以估算： 按式（ 1311），得： 由表 135得，再計算 兩次計算的值相關不打，因此確定。 機體的下面安裝電動機，皮帶輪設置在機體外面，這樣方便調節(jié)皮帶的松緊，檢查皮帶輪的安裝是否到位。 主要改進措施：為了使全過程更趨于機械化，本人從原有基礎上再設計了一個振動分離裝置。 由力學知識，容易得出 tanθ 。滾筒間的固定采用固定板。 通過這次設計又學到了很多 以前沒接觸到的新知識，提高了自己的自學能力。我的設計較為 簡潔 ，但是 高 老師仍然細心地糾正設計內容中的錯誤。最后我要感謝我的母校 —— 湖南農業(yè) 大學，是母校給我們提供了優(yōu)良的學習環(huán)境；另外，我還要感謝那些曾給我授過課的每一位老師，是你們教會我專業(yè)知識。s time for the wild fruits to ripe. The picturesque Arxan in Autumn is indeed a fairyland only exists in a dream that satisfies all your fantasies. If it rains heavily on Saturday night, some elderly Chinese will say it is because Zhinu, or the Weaving Maid, is crying on the day she met her husband Niulang, or the Cowherd, on the Milky Way. Most Chinese remember being told this romantic tragedy when they were children on Qixi, or the Seventh Night Festival, which falls on the seventh day of the seventh lunar month, which is usually in early August. This year it falls on Saturday, August 2. Folklore Story As the story goes, once there was a cowherd, Niulang, who lived with his elder brother and sisterinlaw. But she disliked and abused him, and the boy was forced to leave home with 24 only an old cow for pany. The cow, however, was a former god who had violated imperial rules and was sent to earth in bovine form. One day the cow led Niulang to a lake where fairies took a bath on earth. Among them was Zhinu, the most beautiful fairy and a skilled seamstress. The two fell in love at first sight and were soon married. They had a son and daughter and their happy life was held up as an example for hundreds of years in China. Yet in the eyes of the Jade Emperor, the Supreme Deity in Taoism, marriage between a mortal and fairy was strictly forbidden. He ordered the heaven troop to catch Zhinu back. Niulang grew desperate when he discovered Zhinu had been taken back to heaven. Driven by Niulang39。s Day. More and more young Chinese people begin to celebrate this day in a very similar way as that in western countries. Fewer people than ever will gaze at the heavens on Saturday to pick out the two stars shining bright on either side of the Milky Way, that is, if people even know on which day Qixi falls. There are ready reminders dotted about, in the form of big ads saying Sales on Chinese Valentine39。 Festival. In this day, girls will throw a sewing needle into a bowl full of water on the night of Qixi as a test of embroidery skills. If the needle floats on top of the water instead of sinking, it proves the girl is a skilled embroiders. Single women also pray for finding a good husband in the future. And the newly married women pray to bee pregnant quickly. Tradition transformed The love story of Niulang and Zhinu, and the Qixi Festival have been handed down for generations. Yet these ancient traditions and customs are slowly dying out. Many modern Chinese, particularly youngsters, seem to know more about St Valentine39。 ll wait in the line for one hour to get a ticket, and another two hours at the site, to only see a tiny bit of the place due to the crowds. Last year, 428 million tourists traveled in China over the weeklong holiday in October. Traveling during this period is a matter that needs thorough preparation. If you are short on time to plan the uping Golden Week it may not be a bad idea to avoid some of the most crowded places for now. There is always a place so fascinating that everyone yearns for. Arxan is a place like this. The beauty of Arxan is everlasting regardless of the changing of four seasons. Bestowed by nature, its spectacular seasonal landscape and mountains are just beyond word. Arxan is a crucial destination for the remended travelling route, China Inner Mongolia Arxan — Hailar — Manzhouli. It is also the joint of the four prairies across the SinoMongol