純電動迷你巴士驅(qū)動橋設計[3張cad圖紙+文檔全套資料]

喜歡就充值下載吧。。資源目錄里展示的文件全都有，，請放心下載，，有疑問咨詢QQ:414951605或者1304139763 ======================== 喜歡就充值下載吧。。資源目錄里展示的文件全都有，，請放心下載，，有疑問咨詢QQ:414951605或者1304139763 ======================== 開題報告 （學生填表） 學院： 課題名稱 純電動迷你巴士（驅(qū)動橋設計） 學生姓名 專業(yè)班級 課題類型 指導教師 職稱 課題來源 1. 設計（或研究）的依據(jù)與意義 驅(qū)動橋位于傳動系末端，其基本功用首先是增扭、降速，改變轉(zhuǎn)矩的傳遞方向，即增大由傳動軸或直接從變速器傳來的轉(zhuǎn)矩，并合理的分配給左、右驅(qū)動車輪，其次，驅(qū)動橋還要承受作用于路面和車架或車廂之間的垂直力、縱向力和橫向力，以及制動力矩和反作用力矩。? 汽車驅(qū)動橋是汽車的重大總成，承載著汽車的滿載簧荷重及地面經(jīng)車輪、車架及承載式車身經(jīng)懸架給予的鉛垂力、縱向力、橫向力及其力矩，以及沖擊載荷；驅(qū)動橋還傳遞著傳動系中的最大轉(zhuǎn)矩，橋殼還承受著反作用力矩。汽車驅(qū)動橋結(jié)構(gòu)形式和設計參數(shù)除對汽車的可靠性與耐久性有重要影響外，也對汽車的行駛性能如動力性、經(jīng)濟性、平順性、通過性、機動性和操動穩(wěn)定性等有直接影響。另外，汽車驅(qū)動橋在汽車的各種總成中也是涵蓋機械零件、部件、分總成等的品種最多的大總成。例如，驅(qū)動橋包含主減速器、差速器、驅(qū)動車輪的傳動裝置、橋殼和各種齒輪。由上述可見，汽車的驅(qū)動橋設計涉及的機械零部件及元件的品種極為廣泛，對這些零部件、元件及總成的制造也幾乎要設計到所有的現(xiàn)在機械制造工藝。因此，通過對汽車驅(qū)動橋的學習和設計實踐，可以更好的學習并掌握現(xiàn)代設計與機械設計的全面知識和技能。 本論文的研究目的在于通過對汽車整體的匹配性設計完成驅(qū)動橋的主減速器、產(chǎn)俗氣等部件型號的設計與計算，并完成校核的設計計算。 2. 國內(nèi)外同類設計（或同類研究）的概況綜述 獨立懸架早期只單純用于轎車上，目前大部分輕型貨車和越野汽車為了提高舒適性也開始采用獨立懸架，同時一些中型卡車及客車為了提高駕乘的舒適性和行駛性也開始采用獨立懸架，在國外甚至一些輪式工程機械如吊車和重型卡車也開始采用獨立懸架。因此對于獨立懸架的設計技術(shù)，國內(nèi)外都進行了研究，這些研究主要集中在以下幾個方面：獨立懸架設計方法，獨立懸架參數(shù)對汽車行駛平順性的影響；獨立懸架對汽車操縱穩(wěn)定性的影響。國內(nèi)的研究主要表現(xiàn)為：獨立懸架和轉(zhuǎn)向系的匹配；獨立懸架與轉(zhuǎn)向橫拉桿長度和斷開點的確定；懸架彈性元件的設計分析；獨立懸架的優(yōu)化設計等。國外除上述研究外還進入了微觀領(lǐng)域的研究，如用原子力學顯微鏡觀察懸架材料內(nèi)部聚合體的電子轉(zhuǎn)化情況，研究懸架作為彈性介質(zhì)的流變特性等，從而使得獨立懸架向著智能化，輕量化，小型化，通用化方向發(fā)展。同時由于電子，微機技術(shù)的發(fā)展，使得獨立懸架技術(shù)向著半主動、主動懸架方向發(fā)展。 非獨立懸架早期廣泛應用于除了轎車以外的其它車型中，由于其可靠性和簡單的特性，現(xiàn)在還被廣泛的用于轎車的后橋，輕型貨車和越野汽車的后橋，重型貨車的前后橋都采用非獨立懸架。 由于汽車行駛的平順性和操縱穩(wěn)定性的要求，具有安全、智能和清潔的綠色智能懸架將是今后汽車后橋的發(fā)展趨勢。 汽車驅(qū)動橋是汽車的重要總成，驅(qū)動橋設計是汽車設計的重要組成部分之一。目前國內(nèi)外驅(qū)動橋設計出現(xiàn)了一下一些變化：1、主要部件和功能向驅(qū)動橋的中部集中。有些廠家開始把主減速器,?制動器和行星減速機構(gòu)等集合在橋的中部,?但其優(yōu)點尚待考證。2、橋殼采用球墨鑄鐵,?以提高整橋外觀質(zhì)量。橋殼采用球墨鑄鐵,?加工成本低,?其鑄造及加工后的外觀質(zhì)量均比現(xiàn)在大多采用的鑄鋼橋有了很大的提高。3、適應特種要求的多功能驅(qū)動橋。為適應主機產(chǎn)品的特殊要求,?驅(qū)動橋產(chǎn)品供應廠家設法在橋上增加引進了一些特殊功能:自動充氣功能、超載報警功能、增添轉(zhuǎn)向油缸功能等,?增加了驅(qū)動橋產(chǎn)品的適應性。驅(qū)動橋的結(jié)構(gòu)型式與驅(qū)動車輪的懸掛型式密切相關(guān)。當驅(qū)動車輪采用非獨立懸掛時，都是采用非斷開式驅(qū)動橋；當驅(qū)動車輪采用獨立懸掛時，則配以斷開式驅(qū)動橋。與非斷開式驅(qū)動橋相比較，斷開式驅(qū)動橋能顯著減少汽車簧下質(zhì)量，從而改善汽車行駛平順性，提高了平均行駛速度；減少了其策劃行駛時作用于車輪和車橋上的動載荷，提高了零部件的使用壽命；增加了汽車的離地間隙；由于驅(qū)動車輪與路面的接觸情況及對各種地形的適應性較好，增強了車輪的抗側(cè)滑能力；若與之配合的獨立懸架導向機構(gòu)設計合理，可增加汽車的不足轉(zhuǎn)向效應，提高汽車的操縱穩(wěn)定性。但其結(jié)構(gòu)復雜，成本較高。斷開式驅(qū)動橋在乘用車和部分越野汽車上應用廣泛。非斷開式驅(qū)動橋結(jié)構(gòu)簡單，成本低，工作可靠，但由于其簧下質(zhì)量較大，對汽車的行駛平順性和降低動載荷有不利的影響。 3. 課題設計（或研究）的內(nèi)容 主要研究：純電動迷你巴士的驅(qū)動橋設計。參照純電動迷你客車的基本參數(shù)及相關(guān)汽車的參數(shù)，查閱有關(guān)資料，完成純電動迷你巴士的驅(qū)動橋的計算和結(jié)構(gòu)設計。 4. 設計（或研究）方法 通過查閱汽車構(gòu)造、汽車理論、汽車設計、汽車車身結(jié)構(gòu)與設計、車身造型、汽車車型手冊、現(xiàn)代電動汽車、混合動力電動汽車和燃料電池車基本原理、理論和設計及網(wǎng)上的有關(guān)汽車的資料來進行設計。 5. 實施計劃 第6周 全組集體討論，確定總體方案 第7-10周 完成設計計算，開始繪圖。 第10-12周 完成繪圖。 第13周 按要求整理、編寫設計說明書、整理圖紙及全部設計文件，翻譯英文資料，將全部畢業(yè)設計資料交給指導教師。 第14周 老師審核、互審評閱設計，答辯，評定成績。 指導教師意見 指導教師簽字：年月日 教研室意見 教研室主任簽字：年月日 外文資料譯文 Driving Axle l automobile driving axle The driving axle is one of cross bars supporting a vehicle, on which the driving wheels turn .The driving axle includes a housing ,an axle drive ,a differential , tow axle shafts (half axles ),and final drives (if any ) . The axle .or main, drive is a drive-line unit that increases the torque delivered by the transmission and transmits it to the driving wheels, via the differential. In automobiles, the axle drive shaft, usually called the propeller shaft. The axle drive may be a Single or a double-stage type, the former comprising a pair of gears and the latter .tow pairs of gear. Drive pinion I may be made integral with its shaft, or it may be detachable from the shaft. Driving gears and are usually made in the form of detachable gear rings that are bolted or riveted to the differential case .Alex drive bevel pinions and gears are made with helical teeth in order to reduce noise in operation. The tow-stage axle drive consists of a pair of bevel gears and a pair of spur gears. Drive bevel pinion drives bevel gear that is fixed to the flange of the intermediate shaft made integral with 2nd –stage driving spur gear .Gears meshes with driven spur gear which is fastened to the case rotates in taper roller bearings installed in the differential carrier that makes part of the driving axle housing. The differential is a drive-line unit that divides the torque applied to it between the tow axle shafts and allows one driving wheel to turn at a different speed from the other. The differential consists of case, cross or spider pinion .and side gears, also known as axle gears .the differential pinions are freely mounted on the cylindrical arms of the spider, which is held in the differential case, and remain in constant mesh with the differential side gears. When the automobile is moving down a straight and even road, both driving wheels meet with one and the same rolling resistance. In this case, axle driven gear, or differential ring gear, causes the differential case to rotate .when the differential case rotates pinions and their spider arms move around in a circle with tow differential side gears are meshed with the pinions, the side gears must rotate, causing the axle shafts and their associated driving wheels to turn. With equal resistance applied to each wheel, the differential pinions do not rotate. They apply equal torque to the side gears and therefore both driving wheels rotate at one and the same speed is unequal ,the differential pinions rotate on their spider arms as well as drive round with the differential case .supposing that one of the axle shaft is prevented from rotating ,the differential pinions would have to walk around the stationary side gear ,causing the other side gear to rotate at twice its normal speed .You can now see how the differential can allow one driving wheel to turn faster than the other . Whenever the automobile goes around a turn ,the outer driving wheel travels a greater distance than the inner drive wheel .the inner wheel speeds up proportionately ,thanks to the differential pinions that rotate on their spider arms and ,rolling around the slower side gear send more rotary motion to the outside wheel. The differential side gears are splined on to the inner ends of the axle shafts .The other ends of the shafts are attached to the driving wheel hubs by means of flanges .Trucks use full floating axle shafts .Such axle shafts are acted upon by torque only .All the other loads acting on the driving wheels are taken by the driving axle housing, because the wheel hubs are supported by bearings mounted on the housing. l Driving axle of general-purpose wheeled tractor General-purpose wheeled tractors are a four-wheel drive type, they have tow driving axles-front and rear .Both axles are similar in construction, expect for the housing. Each driving axle consist if a housing, an axle drive ,a differential ,and final drives .The front and rear-axles drives are interchangeable and comprise a pair of spiral bevel gears . The axle drive pinion is made integral with a shaft that is supported by tow taper roller bearings installed in axle drive pinion carrier .The latter is accommodated in differential carrier and is fixed to it by bolts. The flange of the axle drive pinion carrier is provided with threaded holes to fit puller screws that are used to remove the axle drive pinion carrier from the differential carrier .The position of the drive pinion relative to the centerline of the axle is adjust by means of a pack of shims placed under the flange of the drive pinion carrier Shims palace under the cone of the front bearing are used to adjust the preload on the drive pinion bearings. Splined to adjust the preload on the drive pinion shaft is universal-joint flange .The axle drive gear is bolted to the differential case flange. THE DIFFERENTIAL consists of case, four pinions, and tow side gears .The differential case comprise tow halves that are bolted together and supported by taper roller bearings installed in the differential carrier .Screwed in the bearings housing from the outside are nuts used to adjust the backlash between the ring gear and drive pinion teeth and the side bearing preload. Welded to the top of the driving axle housing at both its ends are spring pads .The housing of both its ends are spring axels are provided with filler ,overflow ,and drain holes closed by plugs .Both housing also have vents ,The rotating components of the driving axles are lubricated with transmission oil . As distinct from the automobiles considered in this text, all tractors include final drives in their power trains .The final drives of general-purpose wheel tractors are referred to as wheel-hub reduction gears. While transmitting power to the driving wheels, wheel-hub reduction can increase their torque .These are planetary reduction gear sets consist of sun gear ,or wheel ,three planet ,or pinion ,gears ,planet or pinion ,carrier .stationary internal ,or ring ,gear ,and housing. The sun gear is splined to the outer end of the axle shaft is splined to the differential side gear .The cylindrical planet gears are in constant mesh with both the sun gear and the ring gear and are free to rotate on roller bearings mounted on shafts that are attached to the planet carrier .The planet carrier is fasted to the reduction gear housing by means of studs and nuts .The flange of housing ,driving wheel brake drum 13,and wheel hub are clamped together by bolts .The planet carrier and reduction gear housing form the driven part of the planetary gear set and rotate with the driving wheel of the tractor .The driving gear hub is supported by taper roller bearings mounted on axle shaft housing ,or axle sleeve .The axle sleeve is connected to the stationary ring gear by means of adapter hub that has internal splines and external teeth . The splines are meshed with matching splines on the axle sleeve, and the teeth are meshed with internal teeth ring gear. Wheels and its maintain Modern wheeled tractors and automobiles use pneumatic-tired disc wheels. As a result of the driving wheel tires gripping the road, the rotary motion of the wheels is transformed into the translational motion of the tractor or automobile. According to their purpose, wheels are classified as driving .driven steerable, and combination types. Trucks and general-purpose wheeled tractors have all their wheels of one and the same size .Row-crop tractors have their rear wheels larger than the front wheels .The rear wheels carry the major proportion of the load due to the weight of the tractor .The front wheels are loaded lighter and this makes them easier to turn and provide good directional steering stability, which is essential for row-crop work. A TRUCK WHEEL consists of disc and flat base rim that is made integral with it, while the other flange is formed by detachable side ring that is held to the rim by split lock ring on the rim .which doubles as a side ring and a lock ring. The wheel disc is provided with holes for mounting the wheel on the wheel mounting bolts ,or wheel studs ,on the wheel hub ,where it is fixed by nuts .Both the holes and the nuts are tapered to ensure exact location of the wheel on its hub .The rear driving axles of trucks carry tow wheels at each end .The inner wheels are held to the hubs by cap nuts that are threaded both on the inside and on the outside .and the outer wheels are mounted on the cap nuts and fixed in place by taper nuts screwed on the nuts . The wheel nuts on the right side of truck have right-hand threads, whereas the nuts on the left side of the truck are threaded left-hand .The reason is to tighten the nuts, not loosen them, and thus prevent them from working loose on acceleration and braking. An automobile pneumatic tire consists of casing, inner tube, and flap .The tire casing comprises tread, side walls, and beads .Tires for good roads use small tread patterns, while those for bad roads or cross –country service large tread patterns. The inner tube is made in the form of a hollow elastic rubber doughnut that is inflated with air after it is installed inside the tire and the tire is put on the wheel rim .The inner tube is inflated through tire valve that consists of housing 11,valve inside ,and cap .The valve housing is made of brass in the dorm of a flanged tube that is mounted in the inner tube by means of a washer and a nut and sticks out through a hole in the wheel .Some tire valve housing are of comprise construction :the upper part is made of brass and the lower part ,of rubber that is vulcanized on to the inner tube .The valve inside is a check valve that opens to let air in the inner tube when an air closed ,spring pressure and air pressure inside the tube hold the valve .When the valve is closed ,spring pressure and air pressure inside the tube hold the valve in its seat .It includes core with a rubber ring ,a plunger pin ,and a spring .The valve inside is Screwed in the tire valve housing and is closed by the cap Screwed on the housing. To the construction of the driving and steerable wheels, each wheel comprises hub , disc with rim ,and tire with inner tube .The rim is welded to the disc and the disc is bolted to the hub . The driving wheel tires are of low-pressure type and have heavy tread bars for better traction. The driving wheel hub is keyed to axle shaft and is fixed in place by means of bolted-on insert with worm whose threads mesh with the rack teeth cut in the half axle .By turning the worm one can change the position of the wheel on the axle shaft to obtain the desired track width .Before doing this ,it is necessary to jack up the rear part of the tractor to clear the wheels of the ground and loosen the bolts that hold the inserts to the wheels hubs .Should this adjustment prove insufficient ,the track width can further be increased by placing the wheels with the concaves of their discs facing inwards. On some row-crop tractors ,the rear wheel discs are bolts to lugs welded on the wheel rims .In this case ,the crack width can be changed by bolts the discs in alternative positions to the lugs .Also the concave wheel discs may be used either with the concave facing inwards or outwards. Trouble-free operation of automobiles and wheeled tractors largely depends on the condition of the tires. Therefore, during operation, one should adhere to following rules. Prevent fuel and, or oil from getting onto the tires. Cleans the tires regularly from dirt and remove all foreign articles, such as stones, form the treads. Do not apply brakes sharply, never start away form rest with a jerk, and avoid making sharp turns, for all this causes uneven wear of the tires. Do not allow excessive slipping of the driving wheels. When preparing your tractor or automobile for a long-term storage, jack up the wheels and put trestles under the axles or frame to relieve the tires. The service life of tires is expressed in terms of their mileage. For most bias (ordinary) truck tires, the guaranteed mileage amounts to 50000 km. Observing the above rules will help prolong the useful service life of tires. 驅(qū)動橋 汽車的驅(qū)動橋 驅(qū)動橋是一個支撐車輛的十字交叉的軸，它可以驅(qū)動車輪運動。驅(qū)動橋包括：驅(qū)動橋殼、主減速器傳動軸、差速器、兩個半軸和末端傳動裝置。 主減速器在傳動中的功用是增大變速器傳來的轉(zhuǎn)矩，憑借差速器把它傳遞給驅(qū)動車輪。在汽車中主減速器傳動軸把轉(zhuǎn)矩按正確的方向傳給驅(qū)動輪，通常被叫做推進器。 主減速器有單級和雙級兩種形式，前者包含一對齒輪，后者包含兩對齒輪。主動小齒輪可以和軸做成一個整體，也可以做成分開的。從動齒輪常做成齒圈形式，差速器殼可以用螺栓或鉚釘連接在齒圈上，主減速器的小齒輪和大齒輪可以做成螺旋齒，這樣可以在嚙合時減少噪音。 雙級主減速器包含一對錐齒輪和一對圓柱齒輪，主動齒輪帶動從動錐齒輪旋轉(zhuǎn)而從動錐齒輪和小圓柱齒輪通過中間軸連在一起從而使小圓柱齒輪轉(zhuǎn)動，它與差速器殼固定在一起的大圓柱齒輪嚙合，差速器殼的旋轉(zhuǎn)帶動差速器運動并和軸承裝設構(gòu)成橋殼的一部分。 差速器在傳動系中將轉(zhuǎn)矩分開分別驅(qū)動兩側(cè)半軸，并且允許一側(cè)驅(qū)動輪和另一側(cè)驅(qū)動輪以不同的角速度運動。 差速器包括差速器殼、行星齒輪軸（十字軸），行星齒輪，側(cè)面齒輪即半軸齒輪。行星齒輪可以安裝在卡在差速器殼上的圓柱形十字軸上，并且保持與半軸齒輪的不斷嚙合。 當汽車直線行駛和在水平路面上運動時，兩側(cè)驅(qū)動輪將會遇到相同的滾動阻力。在這種情況下，主減速器從動齒輪帶動差速器殼旋轉(zhuǎn)。當差速器殼旋轉(zhuǎn)時差速器行星齒輪和十字軸也旋轉(zhuǎn)運動，因為半軸齒輪差速器行星齒輪嚙合，半軸齒輪必須旋轉(zhuǎn)，導致半軸與兩側(cè)車輪也運動。當每一個車輪承受的阻力相等時，差速器小齒輪不再旋轉(zhuǎn)，它們給半軸齒輪提供相等的轉(zhuǎn)矩且兩側(cè)車輪以一個相同的角速度旋轉(zhuǎn)。當然，當阻力不相等時，差速器行星齒輪既繞著差速器殼公轉(zhuǎn)又繞十字軸自轉(zhuǎn)，如果一側(cè)半軸不旋轉(zhuǎn)時，行星齒輪不會繞著固定不動的半軸齒輪運動，使另一側(cè)半軸齒輪以平常兩倍的速度旋轉(zhuǎn)。這樣你就明白差速器是怎么使一側(cè)齒輪轉(zhuǎn)速大于另一側(cè)的。 無論什么時候汽車轉(zhuǎn)彎行駛時，外側(cè)車輪總比內(nèi)側(cè)的車輪移過的距離大。內(nèi)側(cè)車輪會慢下來，而外側(cè)車輪則成比例地加速，由于差速器在十字軸上自轉(zhuǎn)，且在速度慢的一側(cè)的半軸齒輪上滾動，它將使外側(cè)車輪移動的快一些。 半軸內(nèi)端用花鍵與差速器半軸齒輪連接，外端用凸緣與驅(qū)動輪輪轂相連。載貨汽車采用全浮式半軸。這樣的半軸只承受轉(zhuǎn)矩作用。其余的負載由橋殼承擔，因為輪轂由安裝在橋殼上的軸支撐的。 輪式拖拉機的驅(qū)動橋 一般的輪式拖拉機采用四輪驅(qū)動的形式，它有兩個驅(qū)動橋——前驅(qū)動橋和后驅(qū)動橋。除了橋殼之外，兩個橋的構(gòu)造很相似。每個驅(qū)動橋都包括橋殼，主減速器，差速器和末端傳動裝置。前后驅(qū)動橋可以互換，且都包含一對螺旋錐齒輪。主減速器的主動錐齒輪與軸做成一體，并由兩對圓錐滾子軸承支撐，并用螺栓與差速器殼聯(lián)接。主動錐齒輪凸緣外有螺紋孔與配套的螺釘，用于防止主動錐齒輪在差速器殼作用下運動。關(guān)系到車軸中心線的主動錐齒輪的位置是由裝在主動錐齒輪后的調(diào)整墊片來調(diào)整的，裝在圓錐滾子軸承內(nèi)座圈的調(diào)整墊片用來調(diào)試安裝在主動錐齒輪上的軸承的預緊力。齒輪軸的軸徑末端的凸緣采用一般的花鍵聯(lián)接。從動錐齒輪用螺栓與差速器殼凸緣固定在一起。 差速器包括差速器殼、四個小行星齒輪，兩側(cè)半軸齒輪。差速器殼由兩部分構(gòu)成，它們用螺栓連接在一起，并由圓錐滾子軸承裝置支撐。軸承套外面的螺母用來避免齒圈和主動錐齒輪發(fā)生運動干涉，使它們正確嚙合，并調(diào)整軸承的預緊力。 焊在橋殼兩端頂部的是彈簧緩沖器，每個橋殼上都有注油孔，并用油塞塞住。每個橋殼都有一個通風孔。橋殼內(nèi)的旋轉(zhuǎn)運動部件都涂有潤滑劑。 在本書之中所有靠末端傳動提供動力的拖拉機與汽車考慮的地方有所不同?？磕┒藗鲃拥囊话阌猛镜妮喪酵侠瓩C有的裝有輪邊減速器。 當傳來的轉(zhuǎn)矩驅(qū)動車輪運動時，輪邊減速器也可以增大扭矩。這些像行星般運動的減速齒輪裝置包括太陽輪、行星齒輪、行星架、齒圈和減速器殼。 太陽輪用花鍵聯(lián)結(jié)在半軸外側(cè)的末端并且用鎖緊螺母擰緊固定。半軸的另一端則用花鍵聯(lián)結(jié)著半軸齒輪。圓柱行星齒輪分別與太陽輪和齒圈嚙合，且繞裝在行星齒輪軸上的滾子軸承自轉(zhuǎn)，行星齒輪軸安裝在行星架上，行星架用螺栓和螺母固定在減速器殼上。減速器殼上的凸緣，制動鼓，輪轂，用螺栓固定在一起，行星架，減速器殼上的行星裝置的運動部件與驅(qū)動輪一起旋轉(zhuǎn)運動。齒輪座由半軸套管上的滾子軸承支撐。半軸套管與固定的齒圈用接合套連接起來，接合套有內(nèi)花鍵槽和外齒。內(nèi)花鍵槽與半軸套上的花鍵嚙合，外齒與齒圈的內(nèi)齒嚙合。 太陽輪驅(qū)動行星齒輪運動，并使固定的齒圈旋轉(zhuǎn)。因為行星齒輪軸與行星架固定在一起，所以行星齒輪可以帶動行星架旋轉(zhuǎn)，并通過減速器殼驅(qū)動驅(qū)動輪運動。 輪邊減速器的部件都通過減速器殼中央的一個孔來注入潤滑油。這個孔有量油尺并用油塞塞住。量油尺上刻有兩個痕跡，一個是減速器殼內(nèi)的最大油位，另一個是其最低油位。 車輪及其保養(yǎng) 現(xiàn)代的輪式拖拉機和汽車都采用充氣式輪胎，輪胎與路面接觸，汽車和拖拉機的車輪滾動來驅(qū)動汽車運動。 按它們的用途分，車輪可分為乘用車用輪胎和牽引車用輪胎以及兩者相結(jié)合的類型。 在貨車及一般的輪式拖拉機中，每輛車所用的輪胎型號是一樣的。農(nóng)用拖拉機后輪比前輪大，后輪承受拖拉機載重的70%，并且后輪能提供更好的牽引力。前輪承受的重量少，它比較容易轉(zhuǎn)向且提供良好的行駛方向，這是農(nóng)用車必不可少的。 貨車的車輪包括輻板, 輪輞，輪輞是焊在輻板上的。當輪輞與一個凸緣做成整體時，與另一凸緣則做成可分的側(cè)擋圈，它是由分裂的擋圈支撐，一些貨車車輪只有擋圈，它包含側(cè)擋圈和鎖環(huán)。 輻板上裝有車輪框架的螺栓孔，在輪轂上有雙頭螺栓，它配有螺母。在輪轂上的孔及螺母安裝在精確的位置。貨車后車橋采用雙車輪，內(nèi)側(cè)車輪有輪轂支撐并由螺母固定，螺栓兩頭都有螺紋，且內(nèi)側(cè)車輪裝有螺母，螺母上的外螺紋用鎖緊螺母固定。 貨車右側(cè)車輪輻板固定螺栓用右旋螺紋，左側(cè)車輪輻板固定螺栓用左旋螺紋。這可以使汽車在行駛中螺母變緊不拖松，并且可以防止它在汽車加速或制動時變松。 汽車可沖氣式輪胎包括外胎、內(nèi)胎和墊帶。外胎有胎冠、棉布層和束帶層。輪胎在良好路面上使用的花紋細而淺，在壞路面上花紋則深而寬。 橡膠輪胎內(nèi)部是中空的，它可以充氣，它裝在輪圈內(nèi)。輪胎充氣用氣門閥充氣的，它包括座筒、閥體和蓋。座筒是有黃銅做成的，它用螺栓和墊片擰緊裝在車輪輪輞上的孔內(nèi)。一些輪胎氣門閥的材料是合成的，上面用黃銅制成，下面用經(jīng)過硫化的橡膠制成的。氣門閥的內(nèi)部有一裂縫，是為了讓空氣能充入輪胎。當氣門閥關(guān)閉時，彈簧壓力和輪胎內(nèi)的空氣壓力使管子恢復原位。它包括帶橡膠環(huán)的氣門芯、活塞和彈簧。 對于農(nóng)用拖拉機的驅(qū)動和前進輪來說，每個輪子都由輪轂，帶輪圈的輪輞，帶內(nèi)胎的輪胎的構(gòu)成。輪圈焊接在輪輞上，輪輞與輪轂用螺栓固定在一起。 驅(qū)動輪的輪胎是低壓的，胎面有深花紋，這可以獲得較好的牽引力。 驅(qū)動輪的輪轂要于半軸相適應，且能代替螺栓，使螺紋與半軸的鍵齒嚙合。轉(zhuǎn)動螺紋可以改變輪子在半軸上的位置，獲得想得到的輪距。那樣做之前需要用千斤頂支起拖拉機的后部，并清潔與地面接觸的輪子，松開螺栓，使其插入輪轂，如果這樣的調(diào)整還不適合，輪距可以通過使輪輞凹面向內(nèi)來進一步加大。 在一些收割機上，后輪輞與焊接在輪圈上的把手用螺栓固定在一起。在這種情況下，輪距可以通過改變在把手上輪輞螺栓的位置來改變。同樣，輪輞凹面可以朝向內(nèi)也可以朝向外。 汽車和拖拉機在使用過程中遇到的問題多數(shù)是由輪胎的狀況引起的。所以，在使用過程中，應遵循以下規(guī)定。 避免燃料或油弄到輪胎上。經(jīng)常清洗污物和胎面上英文字母縫里的沙石。盡量不要緊急制動、不要長時間不清理和避免急轉(zhuǎn)彎。這些因素會使輪胎磨損不均勻。同時也不允許驅(qū)動輪過度滑動。當準備長時間擱置汽車時，要用千斤頂頂起車輪，在車軸下放一個支架或者框架，使車輪受到的壓力得以緩解。 輪胎的使用壽命是用行駛里數(shù)來表示的。對于大多數(shù)普通貨車的輪胎，它的壽命是50000Km。但是如果注意以上的規(guī)定，則可以延長輪胎的使用壽命。 10