【正文】 Ⅳ =45mm lⅢ Ⅳ =47mm dⅣ Ⅴ =52mm lⅣ Ⅴ =20mm dⅤ Ⅵ =58mm lⅤ Ⅵ =12mm dⅥ Ⅶ =52mm lⅥ Ⅶ =20mm dⅦ Ⅷ =45mm lⅦ Ⅷ =47mm 軸上零件的周向定位 齒盤從動輪與軸的周向定位均采用平鍵聯(lián)接。參照工作 要求并根據(jù) dⅡ Ⅲ =42mm,由軸承產(chǎn)品目錄中初步選取標(biāo)注精度級的角接觸軸承 7209AC，其尺寸為 ,估 dⅢ Ⅳ =dⅦ Ⅷ =45mm。 KA工作情況系數(shù)，見表 86 查表 87，取 KA=，帶入公式得： Pca=KAP=*= 選擇帶型 根據(jù)計算功率 Pca 和小帶輪轉(zhuǎn)數(shù) n1有圖表 88選定帶型選擇普通 V帶 Z型。選取 R=180mm, δ m的變化范圍為 ～ 。保證核桃在整個圓周上都產(chǎn)生裂紋，殼的破裂全面而均勻。 6 圖 2 三種擠壓方式的壓縮變形曲線 Figure2 Deformation mode of the three curves extruded 雙齒盤齒板式剝殼原理及最優(yōu)設(shè)計參數(shù) 剝殼原理 在前面分析基礎(chǔ)上，提出了雙齒盤一齒板式剝殼原理 (如圖 3)。 5 核桃的壓縮變形曲線 根據(jù)幾何尺寸關(guān)系，運(yùn)用三角形的余弦定理核正弦定理，就可以求出這三種方案的壓縮變形量 δ（α）與圓盤轉(zhuǎn)角α的關(guān)系式，簡稱壓縮變形曲線。故本文著重研究品種純度較高的云南漾濞縣產(chǎn)的薄殼核桃作為本機(jī)械研究對象。利用軸旋轉(zhuǎn)帶動齒盤的轉(zhuǎn)動，齒弧板固定，從而機(jī)器能夠連續(xù)的工作，大大提高了生產(chǎn)率。 關(guān)鍵詞 ： 核桃；機(jī)械；剝核 2 Design Of Decorticator For Walnut Abstract： It’s necessary to crack walnut by machine. Cracking principle was put forward. The cracking machine and its optimal parameters were designed, which included the Determining totality scheme, the design and calculation of every assembling and every ponents’drawing. After plete the design, analyze the feature, superiority and some defects. Aiming at this defect and raise some improvemeng steps. Keywords： walnut； machine； craking 1 前言 核桃，是人們常見的食物。它營養(yǎng)豐富，具有健腦、補(bǔ)腎、美容、降血脂四大功效。 2 設(shè)計的目的、意義、國內(nèi)外動態(tài) 核桃，在我國有兩千多年栽培歷史，并逐漸由我國西部擴(kuò)展到黃河流域。 3 核桃脫殼機(jī)的總體方案的確定 三種擠壓破裂 方法的比較 擠壓破裂核桃基本上有以下三種方式（如圖 1） 4 圖 1 三種破裂方式 Figure1 Three rupture mode 核桃的旋轉(zhuǎn)角度 采用第一種方式，核桃在圓盤之間沒有旋轉(zhuǎn)，故旋轉(zhuǎn)角 β=0。δ m 是指最大壓縮變形量。當(dāng)核桃喂入到剝殼裝置中，齒盤的旋轉(zhuǎn)帶動核桃邊緣旋轉(zhuǎn)邊向里擠入，一定間距的齒尖不斷地沿著殼表面壓，使得裂紋不斷擴(kuò)展，部分殼和仁分離出來，最后殼基本上完全破裂，碎殼和仁通過最小間隙向下掉出來 。那么，理想擠入角α 3 為： α3=+3176。數(shù)值上比較接近不使仁壓碎的最大擠壓變形量。 確定帶輪的基準(zhǔn)直徑 dd1和 dd2 初選小帶輪的基準(zhǔn)直徑 dd1 根據(jù) V帶截型，參考表 86及表 88，選取 dd1=63mm 驗算帶的速度 V 根據(jù)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(zhǔn)直徑 dd2 確定中心距 a和帶的基準(zhǔn)長度 Ld 如果中心距未給出，可根據(jù)傳遞的結(jié)構(gòu)需要初定中心距 a0,取 即代入 ,得： 初取 a0確定后，根據(jù)帶傳動的幾何關(guān)系，按下式計算所需帶的基準(zhǔn)長度 (42) 將， ,代入上式中，得： 根據(jù) L’ d由表 82中選取和 L’ d相近的 V帶的基準(zhǔn)長度 Ld，取由于 V帶傳動的中心距一般是可以調(diào)整的，固可采用下式作近似計算，即 考慮安裝調(diào)整和補(bǔ)償預(yù)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(jù)（ 86）及對包角的要求，應(yīng)保證 10 確定帶的根數(shù) Z (43) 式中： Kα — 考慮包角不同時的影響系數(shù)， 簡稱包角系數(shù)，查表 85。而 lⅦ Ⅷ =19mm右端滾動軸承采用軸肩進(jìn)行軸向定位。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(biāo)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。（如圖 5） 從軸的結(jié)構(gòu)圖以及彎矩和扭矩圖中可以看出截面 C是軸的危險截面。因此故安全。mm 截面上的彎曲應(yīng)力 軸的材料為 45鋼，調(diào)質(zhì)處理。 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(nèi)部附加軸向力 ,其中 e為表 135中的判斷系數(shù)，其值由的大小來確定，但現(xiàn)在軸承軸向力 A未知，故設(shè)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(guān)不打，因此確定。 主要改進(jìn)措施：為了使全過程更趨于機(jī)械化，本人從原有基礎(chǔ)上再設(shè)計了一個振動分離裝置。滾筒間的固定采用固定板。我的設(shè)計較為 簡潔 ，但是 高 老師仍然細(xì)心地糾正設(shè)計內(nèi)容中的錯誤。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。 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。 并將