599_NJ1062輕型貨車設計（離合器總成設計）

599_NJ1062輕型貨車設計（離合器總成設計）,_nj1062,輕型,貨車,設計,離合器,總成 畢業(yè)設計（論文）任務書 （指導教師填表） 學生姓名 專業(yè)班級 指導教師 課題類型 題目 NJ1062輕型貨車設計（離合器總成設計） 主要研 究內(nèi)容 1. 設計內(nèi)容：參考NJ1062DB輕型貨車，完成所要求條件的輕型貨車離合器及操縱機構設計；繪制離合器與操縱機構總成圖；裝配圖及主要零部件工作圖不少于3張零號圖紙，其中應包含一張以上用計算機繪制的具有中等難度的1號圖紙，同時至少有折合1號圖幅以上的圖紙用手工繪制。 2. 計算內(nèi)容：完成離合器及操縱機構方案分析，完成離合器的設計計算。 3. 設計說明書內(nèi)容：不少于12000字，其中的曲線及插圖全部用計算機繪制；閱讀參考文獻不少于15篇；撰寫中英文摘要，中文摘要400-500字，英文摘要300-450個實詞，關鍵詞一般為4-6個；設計說明書全部用計算機打印。 4. 外文翻譯：完成不少于10000印刷符的外文翻譯（并附原文）。 主要技 術指標(或研究目標) 驅(qū)動型式：4╳2(后驅(qū))；駕駛室：平頭；整車外形尺寸：5995╳2076╳2285；整車整備質(zhì)量：2625kg；額定最大裝載質(zhì)量：2750 kg；軸距：3308 mm；輪距（前/后）：1675/1485 mm；最小離地間隙：213 mm；最高車速：95 km/h；最小轉(zhuǎn)彎半徑：76 00mm； 發(fā)動機型號：YZ4102Q1-1，最大功率 70.6KW/3200rpm，最大扭矩245Nm/2000～2200rpm； 該離合器及操縱機構設計應滿足它們各自系統(tǒng)的基本要求，以及該參考車型的設計要求。 進度計劃 (5周): 調(diào)研、收集、分析資料； (6周): 全組集體討論，制定、確定總體方案； (7～9周): 完成主要總圖設計； (10～12周): 完成零件圖、部件圖、設計說明書等； (13周): 整理圖紙及全部設計資料，上交所有設計資料； (14周): 審核、互審評閱設計； (14周): 答辯，評定成績； 主要參 考文獻 1. 機械設計手冊（1、2、3、4）.機械工業(yè)出版社 或 化工出版社； 2. 汽車工程手冊.機械工業(yè)出版社； 3. 汽車構造教學圖冊. 人民交通出版社； 4. 汽車標準匯編（1～6）.中國標準出版社； 5. 農(nóng)用運輸車標準匯編.機械工業(yè)出版社； 6. 汽車構造、汽車設計、汽車理論。 教研室主任簽字： 年 月 日 CLUTCH The engine produces the power to drive the vehicle. The drive line or drive train transfers the power of the engine to the wheels. The drive train consists of the parts from the back of the flywheel to the wheels. These parts include the clutch, the transmission, the drive shaft, and the final drive assembly (Figure 8-1). The clutch which includes the flywheel, clutch disc, pressure plate, springs, pressure plate cover and the linkage necessary to operate the clutch is a rotating mechanism between the engine and the transmission (Figure 8-2). It operates through friction which comes from contact between the parts. That is the reason why the clutch is called a friction mechanism. After engagement, the clutch must continue to transmit all the engine torque to the transmission depending on the friction without slippage. The clutch is also used to disengage the engine from the drive train whenever the gears in the transmission are being shifted from one gear ratio to another. To start the engine or shift the gears, the driver has to depress the clutch pedal with the purpose of disengagement the transmission from the engine. At that time, the driven members connected to the transmission input shaft are either stationary or rotating at a speed that is slower or faster than the driving members connected to the engine crankshaft. There is no spring pressure on the clutch assembly parts. So there is no friction between the driving members and driven members. As the driver lets loose the clutch pedal, spring pressure increases on the clutch parts. Friction between the parts also increases. The pressure exerted by the springs on the driven members is controlled by the driver through the clutch pedal and linkage. The positive engagement of the driving and driven members is made possible by the friction between the surfaces of the members. When full spring pressure is applied, the speed of the driving and driven members should be the same. At the moment, the clutch must act as a solid coupling device and transmit all engine power to the transmission, without slipping. However, the transmission should be engaged to the engine gradually in order to operate the car smoothly and minimize torsional shock on the drive train because an engine at idle just develops little power. Otherwise, the driving members are connected with the driven members too quickly and the engine would be stalled. The flywheel is a major part of the clutch. The flywheel mounts to the engine’s crankshaft and transmits engine torque to the clutch assembly. The flywheel, when coupled with the clutch disc and pressure plate makes and breaks the flow of power from the engine to the transmission. The flywheel provides a mounting location for the clutch assembly as well. When the clutch is applied, the flywheel transfers engine torque to the clutch disc. Because of its weight, the flywheel helps to smooth engine operation. The flywheel also has a large ring gear at its outer edge, which engages with a pinion gear on the starter motor during engine cranking. The clutch disc fits between the flywheel and the pressure plate. The clutch disc has a splined hub that fits over splines on the transmission input shaft. A splined hub has grooves that match splines on the shaft. These splines fit in the grooves. Thus, the two parts are held together. However, back-and-forth movement of the disc on the shaft is possible. Attached to the input shaft, At disc turns at the speed of the shaft. The clutch pressure plate is generally made of cast iron. It is round and about the same diameter as the clutch disc. One side of the pressure plate is machined smooth. This side will press the clutch disc facing are against the flywheel. The outer side has various shapes to facilitate attachment of spring and release mechanisms. The two primary types of pressure plate assemblies are coil spring assembly and diaphragm spring (Figure 8-3). In a coil spring clutch the pressure plate is backed by a number of coil springs and housed with them in a pressed-steel cover bolted to the flywheel. The springs push against the cover. Neither the driven plate nor the pressure plate is connected rigidly to the flywheel and both can move either towards it or away. When the clutch pedal is depressed a thrust pad riding on a carbon or ball thrust bearing is forced towards the flywheel. Levers pivoted so that they engage with the thrust pad at one end and the pressure plate at the other end pull the pressure plate back against its springs. This releases pressure on the driven plate disconnecting the gearbox from the engine (Figure 8-4). Diaphragm spring pressure plate assemblies are widely used in most modern cars. The diaphragm spring is a single thin sheet of metal which yields when pressure is applied to it. When pressure is removed the metal springs back to its original shape. The centre portion of the diaphragm spring is slit into numerous fingers that act as release levers. When the clutch assembly rotates with the engine these weights are flung outwards by centrifugal forces and cause the levers to press against the pressure plate. During disengagement of the clutch the fingers are moved forward by the release bearing. The spring pivots over the fulcrum ring and its outer rim moves away from the flywheel. The retracting spring pulls the pressure plate away from the clutch plate thus disengaging the clutch (Figure 8-5). When engaged the release bearing and the fingers of the diaphragm spring move towards the transmission. As the diaphragm pivots over the pivot ring its outer rim forces the pressure plate against the clutch disc so that the clutch plate is engaged to the flywheel. The advantages of a diaphragm type pressure plate assembly are its compactness, lower weight, fewer moving parts, less effort to engage, reduces rotational imbalance by providing a balanced force around the pressure plate and less chances of clutch slippage. The clutch pedal is connected to the disengagement mechanism either by a cable or, more commonly, by a hydraulic system. Either way, pushing the pedal down operates the disengagement mechanism which puts pressure on the fingers of the clutch diaphragm via a release bearing and causes the diaphragm to release the clutch plate. With a hydraulic mechanism, the clutch pedal arm operates a piston in the clutch master cylinder. This forces hydraulic fluid through a pipe to the clutch release cylinder where another piston operates the clutch disengagement mechanism. The alternative is to link the clutch pedal to the disengagement mechanism by a cable. The other parts including the clutch fork, release bearing, bell-housing, bell housing cover, and pilot bushing are needed to couple and uncouple the transmission. The clutch fork, which connects to the linkage, actually operates the clutch. The release bearing fits between the clutch fork and the pressure plate assembly. The bell housing covers the clutch assembly. The bell housing cover fastens to the bottom of the bell housing. This removable cover allows a mechanic to inspect the clutch without removing the transmission and bell housing. A pilot bushing fits into the back of the crankshaft and holds the transmission input shaft. Torque Converter The Basics Just like manual transmission cars, cars with automatic transmissions need a way to let the engine turn while the wheels and gears in the transmission come to a stop. Manual transmission cars use a clutch, which completely disconnects the engine from the transmission. Automatic transmission cars use a torque converter. A torque converter is a type of fluid coupling, which allows the engine to spin somewhat independently of the transmission. If the engine is turning slowly, such as when the car is idling at a stoplight, the amount of torque passed through the torque converter is very small, so keeping the car still requires only a light pressure on the brake pedal. If you were to step on the gas pedal while the car is stopped, you would have to press harder on the brake to keep the car from moving. This is because when you step on the gas, the engine speeds up and pumps more fluid into the torque converter, causing more torque to be transmitted to the wheels. Inside a Torque Converter There are four components inside the very strong housing of the torque converter: 1. Pump; 2. Turbine; 3. Stator; 4. Transmission fluid. The housing of the torque converter is bolted to the flywheel of the engine, so it turns at whatever speed the engine is running at. The fins that make up the pump of the torque converter are attached to the housing, so they also turn at the same speed as the engine. The cutaway below shows how everything is connected inside the torque converter (Figure 8-6). The pump inside a torque converter is a type of centrifugal pump. As it spins, fluid is flung to the outside, much as the spin cycle of a washing machine flings water and clothes to the outside of the wash tub. As fluid is flung to the outside, a vacuum is created that draws more fluid in at the center. The fluid then enters the blades of the turbine, which is connected to the transmission. The turbine causes the transmission to spin, which basically moves the car. The blades of the turbine are curved. This means that the fluid, which enters the turbine from the outside, has to change direction before it exits the center of the turbine. It is this directional change that causes the turbine to spin. The fluid exits the turbine at the center, moving in a different direction than when it entered. The fluid exits the turbine moving opposite the direction that the pump (and engine) is turning. If the fluid were allowed to hit the pump, it would slow the engine down, wasting power. This is why a torque converter has a stator. The stator resides in the very center of the torque converter. Its job is to redirect the fluid returning from the turbine before it hits the pump again. This dramatically increases the efficiency of the torque converter. The stator has a very aggressive blade design that almost completely reverses the direction of the fluid. A one-way clutch (inside the stator) connects the stator to a fixed shaft in the transmission. Because of this arrangement, the stator cannot spin with the fluid - it can spin only in the opposite direction, forcing the fluid to change direction as it hits the stator blades. Something a little bit tricky happens when the car gets moving. There is a point, around 40 mph (64 kph), at which both the pump and the turbine are spinning at almost the same speed (the pump always spins slightly faster). At this point, the fluid returns from the turbine, entering the pump already moving in the same direction as the pump, so the stator is not needed. Even though the turbine changes the direction of the fluid and flings it out the back, the fluid still ends up moving in the direction that the turbine is spinning because the turbine is spinning faster in one direction than the fluid is being pumped in the other direction. If you were standing in the back of a pickup moving at 60 mph, and you threw a ball out the back of that pickup at 40 mph, the ball would still be going forward at 20 mph. This is similar to what happens in the turbine: The fluid is being flung out the back in one direction, but not as fast as it was going to start with in the other direction. At these speeds, the fluid actually strikes the back sides of the stator blades, causing the stator to freewheel on its one-way clutch so it doesn’t hinder the fluid moving through it. Benefits and Weak Points In addition to the very important job of allowing a car come to a complete stop without stalling the engine; the torque converter actually gives the car more torque when you accelerate out of a Stop. Modern torque converters can multiply the torque of the engine by two to three times. This effect only happens when the engine is turning much faster than the transmission. At higher speeds, the transmission catches up to the engine, eventually moving at almost the same speed. Ideally, though, the transmission would move at exactly the same speed as the engine, because this difference in speed wastes power. This is part of the reason why cars with automatic transmissions get worse gas mileage than cars with manual transmissions. To counter this effect, some cars have a torque converter with a lockup clutch. When the two halves of the torque converter get up to speed, this clutch locks them together, eliminating the slippage and improving efficiency. NJ1062輕型貨車設計（離合器總成設計） 摘要 在這三個月的時間里，我的最重要的任務之一就是設計汽車離合器、其操縱機構，以及傳動軸的設計。 眾所周知汽車底盤包括傳動系、行駛系和轉(zhuǎn)向系，傳動系部件包括離合器、變速器、傳動軸、驅(qū)動橋、半軸及驅(qū)動輪。在傳動系的這些部件中，離合器和變速器無疑是兩個最為重要的部件。駕駛員通過操縱離合器既可以在變速器換檔時使發(fā)動機與離合器暫時分離，也可以在汽車起步時使發(fā)動機與離合器平穩(wěn)接合。離合器的設計采用膜片彈簧壓緊機構，液壓式操縱機構。在國外，常采用液壓操縱機構的離合器以減輕駕駛員的疲勞， 通過對傳動軸的傳動類型分析，對傳動方式和傳動軸進行了選型；通過對傳動軸的類型與結構分析，選擇了傳動軸的十字軸滾針軸承的密封形式——蓋板式密封。通過對萬向節(jié)的十字軸、滾針軸承、萬向節(jié)叉的設計計算，確定了所設計車輛使用的這些部件的具體尺寸。 綜合各部分的設計及校核結果，所設計的離合器、傳動軸能滿足所設計的輕型貨車的傳動要求。 關鍵詞：離合器，傳動軸，十字軸，操縱機構 THE DESING OF A LIGHT TRUCK (THE CLUTCKAND THE MANIPULATION OF INSTITUTIONS AND SHAFT DESIGN) ABSTRACT In these two month-long time, one of my most vital duties is designs the automobile clutch ,Its control mechanism, as well as drive shaft design. The well known motor car chassis including the power transmission, the travel is and the steering system, the power transmission part including the meeting and parting Transmission gearbox, drive shaft, driving axle, rear axle and driving gear. In power transmission these parts, to Gathering and the transmission gearbox are two most important parts without doubt. The pilot through operates the coupling already to be possible in The transmission gearbox shifts gears when causes the engine and the coupling separates temporarily, also may starts when the automobile cause the engine and Coupling steady joint. The coupling design used the disk spring to contract the organization, hydraulic control organization. In overseas, often uses the hydraulic control organization the coupling by to reduce pilot's weariness. Through to the drive shaft transmission type analysis, has carried on the shaping to the type of drive and the drive shaft; Through to the drive shaft type and the structure analysis, chose the drive shaft cross axle needle bearing seal form to cover the board style seal. Through to the universal joint cross axle, the needle bearing, the universal joint sliding yoke design calculation, had determined designs these parts concrete sizes which the vehicles uses. Synthesizes each part of designs and the check result, designs the coupling, the drive shaft can satisfy skin truck which designs to use the transport vehicle the transmission request. KEY WORDS: Coupling drive shaft cross axle control mechanism 目　錄 前　言 …………………………………………………………………1 第一章 離合器設計分析與方案選擇…………………………………3 §1.1 概述……………………………………………………………3 §1.2 離合器結構方案分析…………………………………………4 §1.2.1　從動盤數(shù)的選擇 …………………………………5 §1.2.2 壓緊彈簧和布置形式的選擇 ……………………6 §1.2.3　膜片彈簧支承形式 ………………………………7 §1.2.4　壓盤驅(qū)動方式的選擇 ……………………………8 第二章 離合器基本參數(shù)和主要尺寸選擇……………………………9 §2.1 離合器基本參數(shù)計算…………………………………………10 §2.2 膜片彈簧主要參數(shù)的選擇……………………………………12 §2.3 扭轉(zhuǎn)減震器的設計……………………………………………13 §2.4 離合器壓盤的設計……………………………………………17 §2.5 離合器從動盤轂花鍵的強度校核……………………………19 §2.6 離合器操縱機構的設計計算…………………………………19 第三章 傳動軸的設計與計算…………………………………………23 §3.1 概　述…………………………………………………………23 §3.2 萬向節(jié)結構方案分析…………………………………………24 §3.3 萬向節(jié)的設計計算……………………………………………24 §3.3.1 萬向節(jié)設計 ………………………………………24 §3.3.2 傳動軸的設計 ……………………………………26 第四章 結 論 …………………………………………………………29 參考文獻 ………………………………………………………………30 致　 謝 ………………………………………………………………31 III