汽車變速器的設(shè)計外文文獻(xiàn)翻譯、中英文翻譯、外文翻譯,汽車,變速器,設(shè)計,外文,文獻(xiàn),翻譯,中英文 外文原文 Automobile Transmission Design Abstract The topic of this project is a design of transmissions for a medium-size truck. The adoption of suitable designs and layout enables the effective utilization of engine to improve the truck's motility and economy. The design was referred to parameters of Beijing Foton truck and relevant books. Via a comprehensive demonstration, the data was collected from various components of the transmission which were modeled by Solidworks. The transmission is a five-speed transmission, including five forward gears and one reverse gear, applying advanced monolithic structure of the intermediate shaft and the shift lock ring-type synchronizer. The gearbox possesses a compact structure, a small size, high transmission efficiency, and a larger ratio range, with good economy and dynamic performance. Keywords: five-speed, intermediate shaft, synchronizer. 1. Introduction The role of transmission: Transmission changes the speed of the engine and exports different rotational speed. At low rotational speed, high torque can be obtained. High speed has better efficiency but the torque is low. So, when you start a machine you need to start at low speed and after running then change high rotational speed maintaining a high efficiency. Specifically, in order to ensure good transmission performance, it should meet the following requirements. 1) Choose the correct gear shift number and transmission gear ratios, and make the optimal matching of engine parameters to ensure that the car has good power and economy. 2) Set neutral to ensure the car engine and the transmission can separate for a long time. 3) Set reverse, so that the car can travel backwards. 4) Set the power output apparatus. 5) Shift quickly, labor-saving, easily. 6) Reliable. During driving, the transmission cannot out-of-mesh, random mesh. 7) Transmission should have a high efficiency. 8) Transmission should be simple, smooth, no noise. 2. Demonstration program 2.1 Select transmission type There are many types of transmissions. By the number of forward gears, transmissions can be divided into three, four, five-speed and the multi-speed transmission, five speed transmission was chosen. According to the shaft of different form, transmission can be divided into fixed shaft and rotating shaft (often with planetary gear transmission) two kinds of transmissions. The main characteristic of fixed axis transmission is easy to realize automatic shift widely used. Two shaft transmission for front engine front-wheel drive. The shaft of rotation type is mainly used for hydraulic mechanical transmission. Fixed shaft type was chosen. According to the number of different shafts, the transmission can be divided into two-shaft transmission, layshaft transmission and multiple shafts transmission. 2.1.1 Two-shaft transmission If the transmission ratio is small, we often choose two shaft types. It has the following characteristics. 1. The gearbox output shaft and the main driving gear speed reducer make it an organic whole. 2. When the engine is longitudinally mounted, the main reducer can use spiral bevel gear or hypoid gear, when the engine is held horizontally, it is tapped with a cylindrical gear, thereby simplifying the manufacturing process. 3. The other gears adopt constant mesh gear transmission, except the reverse gear drive. 4. Most of the synchronizer of gears at the end of the output shaft. 5. If low gear transmission is relatively large, the size of the structure increases, it no longer has the above advantages, it can only drive relatively small conditions before using this program. 6. Two-shaft transmission does not have directly gears, therefore, working at high speed, gears and bearings are bearing, gear noise, and easy to be damaged. 2.1.2 Layshaft transmission From a structural view, there are three shafts: the first and the second shaft are in the same line, and they are directly shifted. When using direct shift transmission, gears, bearings and the second shaft are not loading bearing. The engine torque through the first and second shaft have direct output, and the transmission has high transmission efficiency - up to 90 %. This means that it has less wear and long service life, thus, noise is also smaller. Because the efficiency of direct gear is higher than the other forward gears, it increases the life of the transmission. When the transmission power is transmitted through the first shaft (the intermediate gear shaft and the second shaft), so the distance between them is not too long, but there is still a large transmission gear ratio. High gear uses constant mesh transmission, whereas low speed gear cannot use constant mesh gear. Most transmission schemes except first speed gear shift mechanism are used in synchronization or clutch shift. Few first speed gears are also used to synchronizer type or clutch type shift. Intermediate shaft transmission is widely used in various types of rear-drive cars. That is the reason why the structure is adopted to the design. Twin intermediate shaft transmissions or multiple intermediate shaft types are the mostly used in heavy vehicles. As it does not match with the design, it is not examined further. (Yu, 2009, p.122) 2.2 Gear selection There are two transmission gears: spur gears and helical gears. Spur gear is used for sliding. It is applied in reverse gear and the first gear specifically. The structure is simple and easy to manufacture, but when it is shifting, the root of the gear tooth is prone to bring about noise. That intensifies the wear of gears and lowers the life expectancy. And due to the noise, it easily leads into driver fatigue. Helical gears offer smooth transmission, lower noise, lower wear and longer life. The drawbacks are the axial force generated when working and the structure is complex. This drawback can be balanced when making the calculation of the shaft. By comparing the advantages and disadvantages of the two forms of the gears, reverse and the first speed gear use straight gear, which is considering following factors: the reverse gear and the first speed gear are low usage. Measuring the economy and practicality of the gear structure, the rest of the gears are helical gears, that depends on helical gear has smooth transmission and lower noise. (Yu, 2009, p.126) 2.3 Shift gear structure selection Transmission shift introduces three kinds of forms: straight teeth sliding, gear meshing and synchronizer shifting. 2.3.1: Straight teeth sliding gear This form is easy to manufacture, has a simple structure, but includes various disadvantages. It is prone to impacts due to the shift, leading to fast wearing, lower service life and higher noise. Therefore, it reduces the driving safety and comfort of a car. And technical requirements of the driver are too high, which can influence the driving of the car. 2.3.2: Gear meshing Using a meshing shift increases the number of gear teeth to receive the impact load during the gear shift. In gear meshing, the gear tooth is not involved in the shift, so it is allowing longer life cycle. However, it cannot eliminate shift impact. Therefore, the car safety and ride comfort are affected by a certain amount, and the technical requirements of the driver are too high. In addition, due to adding the mesh and mesh gear, often makes a big moment of inertia of rotating parts of the transmission, so this way of shifting generally is applied to some place without high demand and heavy lorry. 2.3.3 Synchronizer This shift form can eliminate shift shock and the rapid shift. And the manipulation is light. Also, the driver's request is not high. Eliminating noise and shift shock improves the car ride safety, acceleration, comfort and economy. So, modern cars are generally used in this form but due to its complex structure, manufacturing needs high accuracy requirement. The manufacturing of synchronizer is difficult and synchronous ring is easy to damage but it is still widely used. This design adopts this shifting form. (Yu, 2009, p.130) 2.4 The form of reverse selection In order to achieve the reverse drive easily. Cars are equipped with a reverse idle gear between the layshaft and output shaft. This program structure is simple and easy to produce. Figure 2.1 Reverse gears (Drawing by the Solidworks). 2.5 Transmission structure Figure 2.2 Transmission structure (Drawing by hand) 2.6 Synchronizer selection Synchronizer typically has normal pressure type, inertia type and self-servo type. Among them, the inertia type synchronizer is more commonly used. 2.6.1 Normal pressure synchronizer The structure of the synchronization structure is simple. Because the engagement sleeve axial resistance is caused by the spring pressure, the pressure of limited size is not guaranteed. So this form of synchronizer has been applied only on heavy vehicles. The transmission does not use this synchronizer. 2.6.2 Self-servo synchronizer The synchronizer is also known as Boshe Er synchronizer. It can ensure that only in the synchronous state shift, as long as there is the angular velocity difference between clutch and gears, the spring of synchronizer supports force to stop synchronizer ring shrinking, so it prevents movement of meshing sets. Only when the angular speed difference is zero, the spring unloads the load, due to losing the resistance of synchronous ring, shifting process can be achieved. Boshe Er synchronizer has high friction torque, simple structure, reliable operation and short axial dimension. They make transmission in trucks very convenient. 2.6.3 Inertia type synchronizer This form of synchronizer is the same as the normal pressure type synchronizer. It depends on friction effect of synchronization. But it can ensure the joint sets and joint spline gear ring keep distance before the synchronization, and avoid the shock and noise between the teeth. From the structural term, inertia type synchronizer has lock pin type, lock ring type, slider type, chip type and cone type. Although their structures are different, they have the same friction elements, locking elements and elastic elements. 1) The essence of a sliding block type synchronizer is the lock ring synchronizer. It works reliably. It has durable parts but because of the restrictions on the structure arrangement, the bending moment capacity is not big, and tooth surface wear large. So, to be on the safe side, the car does not use this kind of synchronizer. 2) The locking surface of lock ring synchronizer is on the conical surface of synchronous cone ring. That eliminates the teeth of the synchronized cone ring, thus it makes the shaft size is smaller. Considering the rationality of the structural layout, compactness and cone friction torque factors. It is applied for cars and medium trucks transmissions. So this transmission adopts the lock ring synchronizer. 3) The advantage of locking pin type synchronizer is that it has small number of parts, average friction cone radius is larger and torque capacity is improved. The disadvantage is that the axial size is big. So, it is usually for heavy auto transmission. The design does not use this form of synchronizer. 4) The locking surface of cone type synchronizer is still on the synchronization ring joint tooth, but inserting two auxiliary synchronizations between the two cone surfaces. Since the effective area of the cone friction surfaces is exponentially increasing, the synchronizing torque is increased accordingly, thus having a large capacity and a low torque load. This will not only improve the synchronization performance, increase reliability, but also shift power is greatly reduced. If the shift force remains unchanged, the synchronization time can be shortened. Multi-cone synchronizers are used for heavy vehicles. (Liu, 1996, p.175) 2.7 The transmission shaft and parts localization The gears and bearings of output shaft are axial positioned by the snap ring, thrust ring. The axial position of lay shaft is through the snap ring and bearing adjustment shim. Synchronizers are located by shaft shoulder and shaft collar.(Liu, 1996, p.182) Lock ring synchronizer Figure 2.3 The real lock ring synchronizer (Automotive Transmission, 2013,p.1). Figure 2.4 The simulative synchronizer (Drawing by Solidworks) Figure 2.5 The exploded view (Drawing by Solidworks) Figure 2.6 The whole view (Drawing by Solidworks) 中文譯文 汽車變速器的設(shè)計 摘要 本文主要描述一種中型貨車變速器的設(shè)計，通過適當(dāng)?shù)脑O(shè)計和布局，有效利用發(fā)動機(jī)來提高卡車的動力性和經(jīng)濟(jì)性。本次設(shè)計涉及北京福田汽車的參量和相關(guān)書籍。通過一個全面的演示，用Solidworks建好模的變速器的各部件的數(shù)據(jù)都被收集。這是一個五級變速器，其中包括五個前進(jìn)檔和一個倒檔，應(yīng)用先進(jìn)整體結(jié)構(gòu)的中間軸和移位鎖環(huán)式同步器。變速箱具有結(jié)構(gòu)緊湊，體積小，傳輸效率高，且傳動比范圍大，具有良好的經(jīng)濟(jì)性和動態(tài)性能。 關(guān)鍵詞：五級變速，中間軸，同步器 1．引言 變速器的作用： 變速器改變發(fā)動機(jī)轉(zhuǎn)速和轉(zhuǎn)矩。在低轉(zhuǎn)速時，能提供高轉(zhuǎn)矩。高速時不僅效率更高而且轉(zhuǎn)矩較低。因此，當(dāng)你運(yùn)行一個機(jī)器時，你需要能在低轉(zhuǎn)速下啟動，在運(yùn)行換高轉(zhuǎn)速時保持高效率。 具體而言，為了保證良好的傳輸性能，它應(yīng)該滿足以下要求。 1）選擇正確的齒輪換檔數(shù)和傳動齒輪比，并且要使發(fā)動機(jī)參數(shù)的最佳匹配，以確保汽車有良好的電力和經(jīng)濟(jì) 2）設(shè)置空檔，以確保汽車發(fā)動機(jī)和變速器能分離一段時間 3）設(shè)置倒檔，以便汽車倒退行駛 4）設(shè)置功率輸出裝置 5）換檔快，省力，方便 6）可信賴。在駕駛途中，變速器不能脫檔，隨機(jī)嚙合 7）變速器具有高效率 8）變速器應(yīng)該簡單，平滑，無噪音 2．演示程序 2.1 選擇變速器類型 變速器有很多種類。 根據(jù)前進(jìn)檔數(shù)量分，變速器可分為三級，四級，五級和綜合式變速器。在這里選擇五級變速器。 根據(jù)不同形式的軸，變速器可分為固定軸與轉(zhuǎn)軸（常與行星齒輪傳動）2種變速器。固定軸變速器的主要特點(diǎn)是易實(shí)現(xiàn)自動變速，前置發(fā)動機(jī)雙軸傳動前輪驅(qū)動。旋轉(zhuǎn)型軸主要用于液壓機(jī)械傳動。在這里選擇固定軸式。 2.1.1 雙傳動軸變速器 如果轉(zhuǎn)動比小，我們一般選擇雙傳動軸。它有以下特征： 1．變速箱輸出軸和主減速器構(gòu)成一個有機(jī)整體； 2．當(dāng)發(fā)動機(jī)縱向安裝時，主減速器可以使用螺旋錐齒輪和準(zhǔn)雙曲面齒輪；當(dāng)發(fā)動機(jī)保持水平，它是用圓柱齒輪，從而簡化了制造過程； 3．除了反向齒輪傳動，其他的齒輪采用恒定嚙合齒輪傳動； 4．大部分的同步齒輪在輸出軸端； 5．如果齒輪傳動較低，結(jié)構(gòu)尺寸較大增加，它不再有上述優(yōu)勢，它只能驅(qū)動使用此程序前比較小的條件； 6．雙傳動軸變速器沒有直接齒輪，因此，在高速下運(yùn)作時，齒輪和軸承之間有軸承力，齒輪發(fā)出噪音，并且易被損壞。 2.1.2 中間軸變速器 從結(jié)構(gòu)視圖上看，有三個軸：第一根軸和第二根軸在同一直線上，它們能直接轉(zhuǎn)換。當(dāng)直接移位時，變速器，齒輪，軸承和二軸都沒有承載軸承力。發(fā)動機(jī)轉(zhuǎn)矩通過一軸二軸直接輸出，變速器有著高傳輸效率，達(dá)至90%。這意味著它具有較少的磨損和使用壽命長，因此，噪音也較小。因?yàn)橹苯訖n的效率高于其他前進(jìn)檔，所以它增加了變速器的壽命。當(dāng)動力傳輸通過第一軸（中間齒輪軸和二軸），它們之間的距離不太長，但仍有一個大的傳動比。高速檔用常嚙合式傳動，然而低速擋不能用固定嚙合齒輪。大多數(shù)傳輸方案，除了第一變速齒輪換擋機(jī)構(gòu)是在同步或離合器換擋過程中使用的。幾乎沒有第一變速齒輪也被用來同步型或離合器型轉(zhuǎn)變。中軸傳動廣泛應(yīng)用于各類后驅(qū)汽車。這就是為什么采用結(jié)構(gòu)設(shè)計的原因。雙中軸傳動或多個中間軸類型主要用于重型車輛。因?yàn)樗环显O(shè)計，就未進(jìn)一步研究。(Yu, 2009, p.122) 2.2 齒輪的選擇 這里有兩種傳動齒輪：直齒圓柱齒輪和斜齒輪。直齒圓柱齒輪用于滑動，它專門應(yīng)用于倒檔和一檔。結(jié)構(gòu)簡單，易于制造，但是當(dāng)它換檔時輪齒根部容易產(chǎn)生噪音，這加劇了齒輪的磨損，降低了壽命。并且因?yàn)檫@噪音，容易導(dǎo)致司機(jī)疲勞。斜齒輪傳動平穩(wěn)，噪音小，低磨損，壽命長，缺點(diǎn)是工作時產(chǎn)生的軸向力結(jié)構(gòu)復(fù)雜，通過軸的計算可以彌補(bǔ)這一缺點(diǎn)。 通過比較這兩種齒輪的優(yōu)缺點(diǎn)，倒檔和一檔用直齒輪，考慮到以下原因：倒檔和一檔低使用率。衡量齒輪結(jié)構(gòu)的經(jīng)濟(jì)性和實(shí)用性，其余檔位用斜齒輪，這取決于斜齒輪的傳動平穩(wěn)性和低噪聲。(Yu, 2009, p.126) 2.3 變速齒輪結(jié)構(gòu)的選擇 變速器換檔介紹三種形式：直齒滑動，齒輪嚙合和同步器換檔。 2.3.1 直齒滑動齒輪 這種類型齒輪易于制作，結(jié)構(gòu)簡單，但包含各種缺點(diǎn)。易受轉(zhuǎn)向影響，導(dǎo)致快速磨損，使用壽命短和噪音大。因此，它降低了駕駛安全性和汽車舒適性。并且對司機(jī)技術(shù)要求太高，這影響汽車的行駛。 2.3.2 齒輪嚙合 換檔時用嚙合的方式換檔增加齒輪齒數(shù)來獲得沖擊載荷。在齒輪嚙合時，輪齒不參與轉(zhuǎn)換，使它能延長生命周期。但是，它不能消除換檔沖擊。因此，汽車安全性和乘坐舒適性受到一定程度的影響，而且對司機(jī)技術(shù)要求太高。除此之外，由于增加了嚙合齒輪，往往使變速器的旋轉(zhuǎn)部件有一個大的慣性矩，所以這種變速器一般適用于一些要求不高的地方和重型卡車。 2.3.3 同步器 這種換檔方式可以消除換檔沖擊和實(shí)現(xiàn)快速換檔。操作輕便，對駕駛員的要求也沒那么高，消除了噪音和換檔沖擊，提高了汽車行駛安全性，舒適性，動力性和經(jīng)濟(jì)性。因此，現(xiàn)代汽車通常應(yīng)用這種形式，但因?yàn)樗慕Y(jié)構(gòu)復(fù)雜性，制造需要高精度。雖然同步器制造難度大，同步環(huán)容易損壞，但它仍被廣泛使用。本設(shè)計采用這種換檔形式。(Yu,2009, p.130) 2.4 倒檔的選擇 為了實(shí)現(xiàn)反向驅(qū)動容易，汽車在中間軸和輸出軸之間配備了一個反向空轉(zhuǎn)齒輪。這個程序結(jié)構(gòu)簡單，易于制造。 圖2.1 換向齒輪機(jī)構(gòu) （Solidworks繪制） 2.5 變速器結(jié)構(gòu) 圖2.2 變速器結(jié)構(gòu) （手繪） 2.6 同步器的選擇 同步器類型有常壓式，慣性式和自伺服式。在這之中，慣性式同步器比較常用。 2.6.1 常壓式同步器 這種同步器結(jié)構(gòu)簡單，由于彈簧壓力引起的嚙合套筒軸向阻力，這限制的壓力大小是不保證的。因此，這種形式的同步器僅僅適用于重型車輛。變速器不使用這種同步器。 2.6.2 自伺服式同步器 同步器也稱為博舍ER同步。它可以確保只有在同步狀態(tài)轉(zhuǎn)移，只要在離合器和齒輪之間有角速度差，同步器的彈簧支撐力使同步環(huán)停止收縮，所以它可以防止嚙合套運(yùn)動。只有當(dāng)角速度差為零時，彈簧卸負(fù)荷，由于失去了同步環(huán)的阻力，換檔過程可以實(shí)現(xiàn)。博舍ER同步器具有高摩擦力矩，結(jié)構(gòu)簡單，操作可靠性和軸向尺寸短。它們使變速器在卡車?yán)锏膽?yīng)用十分方便。 2.6.3 慣性式同步器 慣性式同步器結(jié)構(gòu)與常壓式結(jié)構(gòu)一樣，取決于同步的摩擦效應(yīng)。但它可以確保接合套和接頭花鍵齒圈在同步保持距離，避免輪齒之間發(fā)生碰撞和噪音。從結(jié)構(gòu)來看，慣性式同步器有鎖銷式、鎖環(huán)式、滑動式、片式和錐式。盡管它們的結(jié)構(gòu)各有不同，但它們有同樣的摩擦元件，鎖定元件和彈性元件。 1）一個滑塊式同步器的本質(zhì)是鎖圈同步器。它工作可靠，具有耐久性，但由于結(jié)構(gòu)布置的限制，彎矩能力不大，且齒面磨損較大。因此，為了安全起見，汽車不使用這種同步器。 2）鎖環(huán)式同步器的鎖面是在同步錐環(huán)的錐面上。這消除了同步錐環(huán)的齒，從而使軸的尺寸較小?？紤]結(jié)構(gòu)布置的合理性，緊湊性和錐形摩擦力矩的影響因素，鎖環(huán)式同步器應(yīng)用于汽車和中型卡車變速器。因此本次變速器采用鎖環(huán)式同步器。 3）鎖銷式同步器的優(yōu)點(diǎn)是零件數(shù)量少，平均摩擦錐半徑較大，扭矩能力提高，缺點(diǎn)是軸的尺寸較大。因此，鎖銷式同步器通常用于重型汽車變速器。本設(shè)計不用這種結(jié)構(gòu)的同步器。 4）錐式同步器的鎖面仍在同步環(huán)齒里，但在兩錐表面插入兩個輔助同步。由于錐形摩擦表面的有效面積是成倍增加，同步轉(zhuǎn)矩相應(yīng)增加，從而具有大容量和低轉(zhuǎn)矩負(fù)載。這不僅提高了同步性能，提高了可靠性，而且大大降低了換擋阻力。如果換檔阻力保持不變，可以縮短同步時間。多錐同步器用于重型車輛。(Liu, 1996, p.175) 2.7 傳動軸及零件定位 輸出軸的齒輪和軸承通過卡環(huán)和推力環(huán)軸向定位。中間軸的軸向位置是通過卡環(huán)與軸承調(diào)整墊片。同步器通過軸肩和軸領(lǐng)定位。（liu，1996，p.182） 鎖環(huán)式同步器（Lock ring synchronizer） 圖2.3 真正鎖環(huán)式同步器 （自動變速器，2013，p.1） 圖2.4 模擬同步器 （Solidworks繪制） 圖2.5 剖視圖 （Solidworks繪制） 圖2.6 全視圖 （Solidworks繪制）