柴油SUV后驅(qū)動橋與后懸架的設(shè)計(jì)

柴油SUV后驅(qū)動橋與后懸架的設(shè)計(jì),柴油,suv,驅(qū)動,懸架,設(shè)計(jì) 車輛與動力工程學(xué)院畢業(yè)設(shè)計(jì)說明書 柴油SUV后驅(qū)動橋與后懸架的設(shè)計(jì) 摘 要 車橋有兩種基本形式：非斷開式和斷開式。非斷開式車橋不轉(zhuǎn)動，而車輪在車橋上轉(zhuǎn)動。最常見的例子就是在馬車上所見到的非斷開式車橋。斷開式車橋與車輪相連接，這樣兩者一起轉(zhuǎn)動。斷開式車橋根據(jù)其承載方式可分為：半浮式，四分之三浮式和全浮式。 后橋與車輪相連，內(nèi)端裝有一個半軸齒輪。差速器殼支撐在左側(cè)車橋上，而且能夠在軸承上做獨(dú)立轉(zhuǎn)動。差速器殼支承在行星齒輪軸上，行星齒輪與兩個半軸齒輪相嚙合。冠狀齒輪與差速器殼相連接，這樣當(dāng)冠狀齒輪由傳動齒輪驅(qū)動轉(zhuǎn)動時，差速器殼也轉(zhuǎn)動。也就是說，驅(qū)動力是從傳動軸末端的傳動齒輪輸送到差速器的。當(dāng)汽車直線行駛時，兩個行星齒輪不在齒輪軸上轉(zhuǎn)動，但卻向兩個半軸齒輪傳遞動力，這樣半軸齒輪與冠狀齒輪的轉(zhuǎn)速相等。從而使兩個后輪也以同樣的速度轉(zhuǎn)動。當(dāng)汽車轉(zhuǎn)彎時，外側(cè)車輪就必須比內(nèi)側(cè)車輪轉(zhuǎn)的更快。為了達(dá)到這一目的，兩個行星齒輪在齒輪軸上傳動，給外側(cè)的車輪提供比內(nèi)側(cè)的車輪更多的運(yùn)動，這樣外側(cè)車輪軸上的半軸齒輪比內(nèi)側(cè)車輪軸上的半軸齒輪轉(zhuǎn)動的更快。 目前使用的懸掛系統(tǒng)基本上為兩種，一種是整體橋與剛板彈簧組成的非獨(dú)立懸架，另一種是使用長短擺臂的獨(dú)立懸架。這些懸掛系統(tǒng)有各種不同的搭配，但是均運(yùn)用相同的工作原理。非獨(dú)立懸掛使用整體式車橋，兩側(cè)用鋼板彈簧連接。通過裝在輪軸和車橋之間的驅(qū)動軸，兩端的車輪可以轉(zhuǎn)動。使用獨(dú)立懸架，每個車輪都可以自由的上下運(yùn)動，幾乎不受另一車輪的影響。 關(guān)鍵詞：車橋，行星齒輪，半軸齒輪，非獨(dú)立懸架，獨(dú)立懸架，鋼板彈簧 DIESEL-POWERED SUV DESIGN REAR AXELS AND SUSPENSION ABSTRACT There are two basic tyes of axle:dead axleds and live axle.The dead axle does not rotate:the wheel rotates on it .A common example is the axle on a horse –drawn wagon.Live axles are attached to the wheel so that both the wheel and the axle rotate together.Live axles are classified accorading to manner in which they are supported:semifloating,three-quarter-floaring,and full-floating. The rear axles are attached to the wheels and have bevel side gears on their inner ends.The differential case isassembled on the left axle but can rotate on a bearing independently of the axle.The differential case supports the differdntial-pinion gear on a shaft,and this gear meshs with the two bevel gears.The ring gear is attched to the differential case so that the case rotates with the ring gear when the latter is driven by the drive pinpion.The driving power enters the diffential throuth the drive pinpion on the end of the ropeller shaft.When the car is on a straight road ,the two differential-pinion gears do not rotate on the pinion shaft ,but they do exert pressure on the side gear,causing both rear wheels to turn at the same speed ,also.When the car rounds a curve ,the outer wheel must turn faster than the inner wheel.To permit this,the two pinion gears rotate on their pinion shaft,transmitting more turning movement to the outer side gear than to the inner side gear.Thus the side gear on the outer-wheel axle turns more rapidly than the side gear on the inner-wheel axle . There are two basic suspension systems is use today.One is the solid axle,leaf spring type;the other is the independent suspension using long and short swing arms.There are various sdaptations of these systenms,but all use the same basic principle.The solid axle suspension uses a solid steel dead axle with a leaf spring at each side.The wheels swivel on each end via a pivot arrangment between the axle and the wheel spindle.With independent suspension,each wheel is free to move up and down with minimum effect on the other wheel. Key word: Rear axles,differential-pinion gear,bevel side fears,solid axle, independent suspension,leaf spring. 符號說明 rr: 車輪的滾動發(fā)半徑 np: 最大功率時發(fā)動機(jī)的轉(zhuǎn)速 vamax: 最高車速 igH: 變速器最高檔傳動比 Temax: 發(fā)機(jī)最大轉(zhuǎn)矩 N: 驅(qū)動橋數(shù)目 iTL: 由發(fā)動機(jī)至所計(jì)算的主減速器從動齒輪之間的傳系最檔傳動比 ηT：上述傳動部分傳動效率 K0：離合器產(chǎn)生沖擊載荷時超載系數(shù) G2: 滿載時一個驅(qū)動輪上的靜載荷系數(shù) ?: 輪胎與路面間的附著系數(shù) rr: 車輪的滾動半徑 ηlB ilB ： 分別為所計(jì)算的主減速器從動齒輪到驅(qū)動車輪之間的傳動效率和傳動比 p：單位齒長上的圓周力 N/mm ig：變速器Ⅰ檔傳動比 d1：主動齒輪節(jié)圓直徑 F：動齒輪的齒面寬 τ: 半軸的扭轉(zhuǎn)應(yīng)力 T ：半軸的計(jì)算轉(zhuǎn)矩 d：半軸桿部直徑 K ：超載系數(shù) Ks：尺寸系數(shù)，反映材料性質(zhì)的不均勻性，與齒輪尺寸及熱處理等有關(guān)。 Km：載荷分配系數(shù) Kv：質(zhì)量系數(shù)，對于汽車驅(qū)動橋齒輪，當(dāng)齒輪接觸良好、周節(jié)及徑向跳動精度高時 目 錄 第一章 前 言 ……………………………………………………1 第二章 驅(qū)動橋的設(shè)計(jì) …………………………………………2 §2.1 驅(qū)動橋概述 ……………………………………………2 §2.2 驅(qū)動橋型式及選擇………………………………………3 第三章 主減速器的設(shè)計(jì) ……………………………………4 §3.1 主減速器結(jié)構(gòu)方案分析…………………………………4 §3.2 主減速比及計(jì)算載荷的確定 …………………………4 §3.3 主減速器齒輪主要參數(shù)的計(jì)算…………………………6 §3.4 主減速器齒輪強(qiáng)度計(jì)算……………………………… 20 §3.5 主減速器齒輪的材料及熱處理 ………………………22 第四章 差速器的設(shè)計(jì) ………………………………………23 §4.1 差速器機(jī)構(gòu)方案分析 …………………………………23 §4.2 差速器齒輪參數(shù)的計(jì)算 ………………………………24 §4.3 差速器齒輪強(qiáng)度計(jì)算 …………………………………26 第五章 半軸及橋殼設(shè)計(jì) ……………………………………28 §5.1 半軸的設(shè)計(jì)計(jì)算 ……………………………………28 §5.2 橋殼的設(shè)計(jì) ……………………………………………31 第六章 后懸架 ………………………………………………33 §6.1 鋼板彈簧的設(shè)計(jì) ………………………………………33 §6.2 筒式減振器 ……………………………………………35 第七章 結(jié) 論……………………………………………………37 參考文獻(xiàn) …………………………………………………………38 致 謝 ……………………………………………………………39 IV