FEV Inc. is again sponsoring the FEV Powertrain Innovation Forum at the SAE World Congress (slated this year for April 13-15 in Detroit, MI) for high-level discussion of hot automotive industry topics. At its booth, the company will be showcasing a number of hot high-tech products including its new internally developed seven-speed hybrid transmission. The 7H-AMT unit is equipped with an electric motor to eliminate torque interruption, a major disadvantage of automated manual transmissions (AMT) usually found in smaller vehicles where shift comfort does not play a key role.
Torque interruption is eliminated because the transmission configuration provides two independent torque paths—one for the internal-combustion engine (ICE) and one for the electric motor. During ICE gear shifts, the electric motor fills the torque gap that would usually occur in a conventional AMT.
The transmission has a torque capacity of 320 N·m (236 lb·ft) and provides 7+R gear ratios for the ICE and 3+R ratios for the electric motor without increasing the complexity and part count of a comparable conventional AMT. In addition, one long 1st gear and one long reverse gear are available for the ICE.
The transmission was designed to be ultracompact and thus able to be installed transversely, paving the way for wider use of extremely fuel-efficient transmissions in smaller vehicles. It offers the same torque range of a six-speed and features all standard operating modes of a full hybrid transmission, according to FEV, including start/stop and boosting/regeneration in all gears.
All-electric driving is possible when using the first electric motor gear and is sufficient for most urban driving situations. When more torque is needed, the ICE is started by controlled slip of the clutch and precise modulation of electric motor torque.
The 7H-AMT was developed by a global team using the company's hybrid experience, including FEV's Hybrid-Electric Vehicle Development Center in Auburn Hills, MI.
Among other FEV products to be displayed are the Extreme Downsized Engine, developed in anticipation of stringent new emissions laws due to take effect in both Europe and the U.S. After analysis of the varying technologies, the company determined that downsizing and boosting are the best ways to meet the needs of the market. Harnessing the potential of a combination of boosting and direct-injection technologies, FEV engineers created a turbocharged two-valve SOHC three-cylinder engine with 698-cm³ (42.6-in³) displacement, which is based on the Smart fortwo Brabus engine.
DI is integrated by replacing the twin spark ignition with a single spark plug on the exhaust side and the DI device in place of the removed spark plug on the intake side. The DI spray pattern layout was accomplished in accordance with FEV’s injector layout process, which combines an early base geometry layout with the FEV Multi-Layout Tool toward reduced wall wetting and the FEV Charge Motion Design. Prevention of wall wetting through this method ensures low content of fuel in oil.
With a bore diameter of 66.5 mm (2.62 in), the Extreme Downsized Engine is the smallest competing powertrain in this market segment, according to FEV.
FEV also will be displaying turbocharger and battery-management technology.