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With the 8HP transmission generation, ZF established a model range on the market offering considerable progress in terms of fuel savings, power-to-weight ratio, and functionality. A front-transverse transmission derived from the 8HP transmission generation gear set concept leads to higher design costs and to an unfavorable design, contradicting the very restricted installation spaces for front-transverse transmissions. With the transmission concept of the 9HP48 transmission, the advantages of the 8HP transmission generation were successfully transferred to a front-transverse transmission design and, at the same time, all restrictions regarding the installation space were solved. Thanks to its number of gears the high efficiency and the reduced drag torque, the 9HP48 transmission delivers fuel savings of up to 16 percent compared with today's standard 6-speed automatic transmissions with front-transverse installation.

The legislative and market pressure for CO2 reduction and fuel efficient powertrains lead to a variety of automatic transmission concepts in recent years. The CVT technology, the dual clutch technology (DCT) and optimized architectures of torque converter / planetary gear based automatic transmissions (AT), such as 6, 7, and 8 speed ATs entered the market in the last decade. Also different hybrid technologies have entered the market offering further improvement for fuel consumption especially in city driving. Helpful for OEMs and suppliers to flexibly meet market demands proofed the use of modular hybrid solutions. Clear demand to meet were packages of existing vehicles and powertrains with AT and hybrid transmission (HT), e.g. the modular transmission kit based on the ZF 8 speed AT. Hybrid technology is offering fuel efficiency benefits, but there are also reasons for a slow market penetration.

This paper presents an introduction to the requirements for shock absorbers in e-vehicles by means of a comparative study of two pure-electric vehicles from different OEM's tested in real road conditions. In this investigation the focus was on the shock absorbers, the most critical suspension components with regards to ride comfort. Different damper designs were used to investigate both in the vehicle and on the test bench. The results of the analysis in the time and frequency domains are presented.

In view of legal requirements and measures for climate protection, fuel efficient vehicles have become increasingly important. Against this background, transmissions are a key factor for two main reasons: Energy consumption and emissions can be reduced by optimization of conventional transmissions. The "ideal" transmission has a potential of contributing to this goal by about 10%. Between 4 and 5% out of this 10% can realistically be achieved. Driveline electrification constitutes another necessary step for CO₂ savings. To this end, an ideal option is integrating the electric components into the transmission. In view of the uncertain market development for hybrid car demand, a modular approach to electrification in transmissions is essential. This article outlines the electrification approach.

The worldwide increasing acceptance and success of modern automatic transmissions in passenger cars is based on innovative technology, driving comfort, shifting dynamic and - most important - fuel consumption reduction. New concepts are facing the challenge of further improvements in internal efficiency and very tough future goals on CO2 emissions in connection with more sophisticated gasoline and diesel engine technologies. Based on the competition and current diversity in automatic transmission concepts, high investments in production facilities must be taken also well into account when thinking about follow-up technologies of installed 8-speed and 9-speed technologies. This must also be considered for the different demands in regions and markets. So, how may a successful automatic transmission system look like in 2020 and beyond? Do we have even more gears than the current 8-speed and 9-speed? Does it make sense to increase the total gear ratio any further?

Hydrodynamic launch elements, from the Foettinger principle of the torque converter to the first series production HCC wet clutch, are becoming more relied on in the transmission world for their high power density, launch comfort, and vibrational isolation capability. In order to attain the ambitious fuel economy objectives of the future, engine vibrations have to be successfully isolated from the driveline at low engine speed ranges without the use of the hydrodynamic circuit. This is now all the more challenging as new combustion engines are producing higher torsional vibrations as a result of fewer cylinders, higher combustion pressures, cylinder deactivation, and lower critical speeds. This paper will describe the next generation of powertrain vibrational isolation, dampening via powersplit. Additionally, a next generation wet launch element, the Hydrodynamically Cooled Clutch will be discussed.

Under the name “ZF ECOnnect”, ZF has recently developed a variety of AWD driveline solutions with an available AWD disconnect function. The ZF AWD disconnect systems are mainly designed for FWD-based AWD architectures and greatly help to solve the conflict between AWD performance the additional fuel consumption caused by AWD in comparison to FWD. AWD disconnect means that when no AWD function is required, there will be no torque transfer to the secondary axle. Therefore, the speed-dependent losses due to friction and oil churning are avoided by bringing the normally rotating elements to a standstill, while the vehicle is still driving. Compared to a conventional hang-on AWD system, the disconnect system therefore reduces the friction losses in the AWD driveline by up to 90% in the disconnected mode. This is achieved by the overall design of the units including special features and optimized coupling elements resulting in very low drag torque.