ZF AS Tronic系列-适用于各种商用车辆的自动变速器外文翻译

1、The ZF AS Tronic Family Automotive Transmissions forAll Commercial Vehicle Classes1 Requirements for Commercial Vehicle Transmissions Customers demand high efficiency along with increasing vehicle comfort and safety. As an independent transmission manufacturer, ZF customer needs include the needs of

2、 drivers, forwarding companies, and vehicle manufacturers.Therefore, ZF considers the many requirements that a new transmission concept must fulfill when developing a transmission, Figure 1 . 图1商用车辆的需求Fig. 1 Requirements for commercial vehiclesKeeping costs low is a considerable challenge, initially

3、 in terms of acquisition and later during operation. That is why fuel consumption is increasingly one of the decisive vehicle features that separate the competition. A modern transmission can make an important contribution here: On the one hand by improving efficiency and on the other hand in automa

4、tic transmissions by the optimal selection of the gear ratio dependent on the driving situation. Reducing the transmission, s weight also leads to reduced costs: Using less material reduces acquisition costs and enabling a higher payload reduces operating costs. On the one hand, decreased oil consum

5、ption contributes to environmental protection; additionally, it has an immediate influence on the costs, however, that accrue throughout the vehicle s service life.The demand for system comfort increasingly approaches the standard set by car technology, whereas in this case limits are set by mass ra

6、tios and cost constraints. Low noise emissions are a result of legal regulations on the one hand but also contribute to more comfortable driver workplaces when met. Furthermore, electronic systems increasingly support the driver and relieve him/her from routine tasks. This benefits safety in traffic

7、.2 Advances with Automatic TransmissionsAutomatic transmissions can satisfy many of the demands that customers make on commercial vehicles considerably better than manual transmissions. Despite the fact that automatic transmissions are generally more expensive, if one takes the complete installed ma

8、nual transmission system including the gearshift system into account, the difference in acquisition costs is no longer as great. Moreover, the goal of future developments is to further reduce the costs for automatic transmissions.Even today the higher acquisition costs are already paying for themsel

9、ves relatively quickly due to lower operating costs so that automatic transmissions are economically advantageous in the long run. The efficiency of the AS Tronic family of transmissions is comparable to a manual transition; however, as a rule, the shifting point selection is better due to the appli

10、cation of an automatic driving strategy, which positively affects fuel consumption. A long term study conducted by ZF and DEKRA found that the automatic shifting point selection represents the consumption performance of a very good, concentrated driver. Thus, averaging all drivers and driving situat

11、ions in a commercial fleet, consumption is reduced on the order of 3 percent since the engine operates reliably in the optimum speed range with regard to fuel consumption; a process that is controlled independently of the driver, s qualification.An additional advantage in terms of operating costs is

12、 reduced clutch wear. Reduced differential speeds during starting and shifting operations lengthen the service life of the clutch, which has al so been proven in long term tests. Many vehicle manufacturers take this into account and offer a significantly longer warranty cover on the clutch in AS Tro

13、nic transmissions.By automating the clutch, the clutch pedal is no longer needed, which clearly simplifies operation for the driver, particularly in stop and go traffic or when maneuvering. The automatic gear selection relieves the driver from shifting as well, whereby he/she can concentrate better

14、on road traffic. However, at the same time, the driver can engage manually at any time, for instance in driving situations where the drivers forward field of vision is in question. This takes place according to Shift by Wire via an electromechanical control switch so that only very little actuating

15、forces are applied when manually selecting gears. The rapid automatic shifting and the protection against operating error also contribute to the increase in driver comfort while at the same time protecting the transmission and driveline. In addition, the absence of a mechanical link between shift le

16、ver and transmission reduces cabin noise.Using an automatic transmission also has advantages for vehicle manufacturers. Like the clutch control, the complete shift linkage is no longer needed, which makes both left and right hand steering vehicles easy to manufacture. When designing the driver workp

17、lace, anything is possible in terms of operating the transmission.3 The ZF AS Tronic FamilyZF began developing automated manual transmissions for commercial vehicles early. The first product was a partially automated transmission with automatic pre selection, which was introduced into the market in

18、1984. Ten years later, an automated transmission followed with the introduction of the first AS Tronic; however, the driver still had to select gears. Its successor model was first equipped with an intelligent shift program, which has been in production since 1998. Thus, a fully automatic solution w

19、as offered in a heavy commercial vehicle for the first time.The chosen transmission concept for AS Tronic resulted in the most efficient solution possible for larger volumes. Extensive integration and removal of unnecessary components opened up potential cost savings. As a group drive, AS Tronic is

20、designed with an unsynchronized basic transmission and synchronized splitter and range change group, Figure 2. 图2 ZF AS Tronic的3D剖示图Fig. 2 ZF AS Tronic: 3D section cut In order to reduce the weight of the transmission, a design with two countershafts was chosen, which is optimal in this performance

21、class in terms of weight. Due to a modular design and a basic transmission with 3 or 4 speeds, l6 peed, 12 speed, and 10 speed variants could be represented.In the basic transmission, the synchronizations were replaced with shift dogs, because the synchronization can take place by controlling the in

22、ternal combustion engine in modern EDC engines. An additional transmission brake is then required for up shifts, which is located on one of the two counter shafts. A standard dry clutch is used. It is fully automatic so that a clutch pedal is no longer necessary. All automated components are pneumat

23、ically operated and are combined within modules that are integrated into the transmission housing. The coordinated operation of transmission, clutch, and engine takes place by electronic control, which is located in the shift module. The interfaces to the out side were minimized.AS Tronic was initia

24、lly limited to torques of 2, 300 Nm (12 speed) and 2, 600 Nm (16 speed). Afterward, variants were introduced in a two step development, which expand the torque ranges of 12 speed transmissions upwards. AS Tronic is offered in direct drive and overdrive designs and is generally available with an inte

25、grated secondary retarder “Intarder. Automatic transmissions have found increasing acceptance in heavy commercial vehicles in the past few years and enjoy enormous popularity among customers. However, the advantages of these transmissions are also demonstrated especially in light and medium duty com

26、mercial vehicles. Vehicles in these classes are primarily used in city and regional traffic. Relief from operating the transmission and the clutch is especially important in this case because the traffic environment requires the drivers full attention. Furthermore, this sector is marked by a high nu

27、mber of untrained drivers and frequent driver turnover. Therefore, reducing the drivers influence on fuel consumption and clutch wear is an unmistakable advantage, not to mention safeguarding against transmission and clutch damage caused by the driver.For these reasons ZF decided to expand the produ

28、ct portfolio for automatic transmissions systematically into the area of low torques, Figure 3. 图3变速器型谱:ZF AS Tronic的转矩范围Fig. 3 Transmission portfolio： the ZF AS Tronic products with torque rangesStarting from the technical fundamental principle- two pedal solutions with automatic shifting and a cus

29、tomer benefit that is commensurate with the AS Tronic- smaller AS Tronic transmission will be developed as well. They receive additional coding to their genuine designation in order to mark their association to the respective vehicle applications. AS Tronic mid will be used for applications from 800

30、 Nm to 1, 600 Nm； AS Tronic lite will cover trucks in the lower torque range up to 1, 050 Nm with 6 speed transmissions.4 ZF AS Tronic midThe vehicle sector where the AS Tronic mid series will be used is very sensitive to price and highly differentiated in terms of application types. Thus, midrange

31、vehicles will service both distributor and long distance transport as well as construction sites. Therefore, one of the focal points of development lies in a cost effective design that will fulfill the many and diverse customer requirements easily and also cover the wide torque range.Consistent prod

32、uct planning led to the development of an uncompromising midrange transmission series designed for automation. It encompasses seven transmission types combined into one modular design. With 840 mm short and 900 mm long transmission variants, the modular design concept is primarily based on the varia

33、tion of the wheel widths in order to cover the torque ranges up to 1, 200 Nm and 1，600 Nm respectively. Both transmission lengths will be offered in direct and overdrive de signs. Compared to the AS Tronic, the AS Tronic mid transmissions are approx. 50 to 65 kg lighter. In order to optimize costs,

34、a consistent complexity management system was pursued. Approximately 40% of the components were taken from existing transmissions in production at ZF.In order to offer uniform automation technology for all commercial vehicles in the midrange and heavy duty sectors, the proven AS Tronic components su

35、ch as transmission/clutch actuators, electronics, and software were used. Due to the inter face equality this achieved, the vehicle manufacturer can offer both AS Tronic and AS Tronic mid series in almost identical vehicles with various drive line variants at minimal expense.In a preliminary concept

36、 study, various gear set concepts were considered. Eight gear set formulas were compared using eleven selected evaluation criteria in terms of function, costs, and deadline. In order to provide this complex decision matrix with the necessary transparency, a decision making software tool was used. Th

37、e choice was made for a 12 speed gear set (2x3x2), which is comparable to a conventional 9 speed gear set in terms of design space and weight and even has advantages compared to a 10 speed gear set, Figure 4.图4 ZF AS Tronic mid变速器剖示图 Fig. 4 ZF AS Tronic mid in complete viewIt consists of engaging an

38、d disengaging input constants ( splitter group), 3 speed main transmission, and an output end planetary drive stage (range change group). Synchronizations are used in the splitter and range change group; the main transmission shifting elements are designed as dogs. The gear steps has a slightly prog

39、ressive gear interval due to a small increase in the gear ratio. Thus, at a total gear spread of approx. 12. 8, the gear ratio of 23. 8 % from 11th to 12th speed is on par with a comparable 16 speed transmission. For the first time, the gear ratio of the reverse gear was designed 13. 1, i. e. slower

40、 than 1st gear on a range change group transmission by an offset engagement over the reverse idler gear. In close cooperation with the customers, high drivability was already emphasized in the specification phase. Upon completion of the rough design, the drivability release criteria of one customer

41、were already proven in simulations.A detailed cost analysis of the gear units in ZF transmissions led to the design of the planetary rear mounted range change group in the AS Tronic mid，in which the most cost effective solutions were adopted in each case. Thus, the design of the new gear unit is mar

42、ked by the synchronization of the AS Tronic and the gear set design of the Ecosplit Figure 5. 图5 ZF AS Tronic mid:行星齿轮传动Fig. 5 ZF AS Tronic mid： planetary drive detail The bearings of the swing fork in the range change group are realized between the two housing parts, which minimizes seal points to

43、the outside and possible corrosion weak points. The clutch actuating cylinder was turned in driving direction from the 6 o clock position for AS Tronic to the 8 oclock position for AS Tronic mid. This not only increases vehicle road clearance and brings the actuating cylinder out of the danger zone,

44、 it al so offers the flexibility to react to potential requirements pushed clutch release under compression.Different from the AS Tronic, the AS Tronic mid gear set will only be designed with one counter shaft. The solution was the best in a parameter study for the torque range considered, which tak

45、es into account both the modular design aspects as regards optimal gear set length variation as well as the legally permitted noise requirements. As a result, the developer faced an additional challenge. If the oil pump and transmission brake are each driven by one countershaft in the AS Tronic, the

46、n both components now must be combined in a joint, cost effective brake pump module.Maximizing transmission efficiency in order to reduce fuel consumption attracted much interest during development. By consistently changing splash lubrication to injection lubrication, quasi dry sump lubrication was

47、achieved so that diving losses do not occur. In order to optimize the lubrication system, oil flow calculations were conducted. The oil itself was handled like a structural/ design element. ZF has worked intensively for years with lubricant manufacturers in order to develop synthetic oils such as th

48、e ZF Ecofluid M, which is used in these transmissions. This oil has low viscosity and therefore contributes low internal losses; however, at the same time it offers sufficient lubricating film to guarantee the service life of gears, bearings, and synchronizations. An additional advantage of Ecofluid

49、 M is high stability, which makes clearly longer oil change intervals possible and greatly reduces oil consumption.Shift dogs in the main transmission and a com pact transmission design with small center distance also contribute to loss reduction. All these measures together increased the efficiency

50、 in the direct gear from 99. 2 to 99. 6% under comparable operating conditions. Active heat management enabled additional fuel savings. If the transmission runs at approx. 60 oil sump temperature on road, the oil viscosity can be further reduced by additionally heating to 80. In this case, AS Tronic

51、 mid is optionally available for the addition of a highly integrated heat exchanger. Short payback periods of approx, one year are ensured by cost effectively integrating the heat exchanger cartridge with the integrated bypass valve in the oil circulation on the intake side.ZF AS Tronic系列-适用于各种商用车辆的

52、自动变速器1商用车辆变速器的需求客户的要求是在提高车辆舒适性和平安性的同 时也提高效率。作为一个独立的变速器制造商，ZF 公司的客户还包括驾驶人员、运输公司和车辆制造商。因此，ZF认为在开发变速器时就必须考虑到应 满足各种需求，图1)。图1商用车辆的需求Fig. 1 Requirements for commercial vehicles继续降低制造和使用本钱是一个很大的挑战。这就是燃油经济性为什么正成为车辆竞争的决定性因素之一的缘故。一个现代化的变速器具有以下奉献：一方面通过优化速比改良效率、实现自动化、降低变速器重量以减少本钱、减少金属材料用量降低制造本钱、提供更大的有效载 荷降低使用本钱

53、等。另一方面，减少燃油消耗还有助于环境保护，它直接影响到使用本钱，因而可提高 车辆的效劳寿命。对系统舒适性需求的增加已成为车辆技术的标准配置，尽管这受制于档位数量和本钱限制。低噪声一方面是由于法规要求，同时也提高了驾驶员工作环境的舒适程度。进一步而言，为驾驶员提供支持的电子系统减轻了他们的工作任务。这有益于交通平安。2自动变速器的优点自动变速器比手动变速器更能满足客户对商用车辆的需求。除了自动变速器本钱较高的事实外，但如果考虑到手动变速器及相应的换档操纵系统的话，两者本钱的差距并不太大。因此进一步开展的目标是降低自动变速器的本钱。在今天，较高的制造本钱由于更低的使用本钱而迅速补偿，因此自动变速

54、器最终具有经济性方面的优势。将ZF AS Tronic系列变速器与手动变速器相比，由于采用了自动驾驶模式其换档点的选择更具优势，这有助于燃油经济性。一项由ZF和 DEKRA公司的长期研究发现换档点的自动确定相当于一个具有高超技术驾驶员集中精力的驾驶。因而一个具有平均驾驶水平的车队燃油消耗可降低 3%，因为发动机能可靠地工作在最正确速度区域，而整个过程与驾驶员的素质无关。另一个优点是可降低离合器的磨损。在起步和换档过程中减少滑差可增加离合器的使用寿命，这己被长期试验所证明。许多车辆制造商为配置AS Tronic变速器的车辆提供更长的离合器保修期限。采用自动离合器后，离合器踏板己不再需要，简化了驾

55、驶员的工作，特别是在频繁起步、停车工况下。档位自动选择解放了驾驶员的换档动作，驾驶员的注意力可集中在道路交通上。同时,驾驶员仍可在任何时候切换为手动模式，例如当驾驶员视野出现问题时。这些都根据线控换档系统和机电一体化的控制开关完成，因此在手动换档时仅需很小的操纵力。迅速地自动换档和防止操纵失误增加了驾驶舒适性，同时也保护了变速器和传动系。另外变速器和换档操纵杆之间无机械联接可降低驾驶室的噪声。使用自动变速器对车辆制造商也有好处。像离合器控制和换档操纵装置己不再需要，方便制造转向盘左置和右置的车辆。在设计驾驶员工作区域时更能随心所欲。3 ZF-AS Tronic 系列ZF早就开始开发适用于商用车

56、辆的机械自动变速器。第一个产品是带自动预选档位的半自动变速器，在1984年投入市场。十年后，推出的是AS Tronic的第一代产品，但是驾驶员仍需要选择换档。在1998年，其后续产品采用了智能化的换档程序，而全自动化的产品那么首先用于重型商用车辆。图2 ZF AS Tronic的3D剖示图Fig. 2 ZF AS Tronic： 3D section cut选择ZF AS Tronic变速器将具有更好大批量装车的可能性。高度集成和省略不必要的元件使得在降低本钱方面仍具潜力。作为一组合式变速器，AS Tronic被设计成由不带同步器的主变速器、前置同步分流的副变速器和扩展速比的后置副变速器组成，

57、图2。为减轻主变速器的重量，采用了双副轴结构。由于主变速器是3或4档，因此可构成16、12和10档的变速器。在主变速器，同步器被换档档块所替换，因为同步过程可由现代化的EDC发动机完成。一个附加的变速器制动装置用于升档，它位于两副轴之一上。采用标准的干式离合器。由于是全自动变速器故无需离合器踏板。所有的换档元件由气压操纵并被以模块形式集成在变速器壳体上。利用电控系统控制变速器、离合器及发动机，该装置安装在换档模块上。外部界面做成最小。AS Tronic的输入转矩为2300Nm(12速和 2600Nm(16速。副变速器具有2档速比，它能扩大12速变速器的转矩。AS Tronic提供直接传动和超速

58、，通常集成一个第二缓速器“Intarder。在过去几年里，自动变速器在商用车辆上的应用正在增加并赢得了消费者的巨大信任。然而，变速器的优点主要表达在轻型和中型商用车辆上。这些车辆主要行驶在城市和近郊交通繁忙的区域。这时减轻变速器和离合器的操作特别重要，因为交通情况需要驾驶员集中全部精力。另外，车辆是由大量非专业人员驾驶而且频繁更换驾驶员。因此减少驾驶员对燃油消耗和离合器磨损的影响是一个显著的优点，同时也减少了驾驶员对变速器和离合器的伤害。为此ZF决定系统地扩展自动变速器的产品型谱，如图3。图3变速器型谱:ZF AS Tronic的转矩范围Fig. 3 Transmission portfolio： the ZF AS Tronic pr