At a Live Drive Event in Marshall Michigan, Eaton highlighted a number of new products to reduce fuel consumption and emissions, including an all-new electronic limited slip differential; an electronic fuel vapor management valve for hybrid-electric vehicles; a range of next-generation variable valvetrain systems; and new engine valve product designs.
The diversified manufacturer also said that in addition to boosting engine performance, its superchargers can provide up to a 5% fuel savings and reduce emissions compared to competing technologies.
Electronic Limited Slip Differential. The all-new electronic limited slip differential, Ultra Posi is designed for front and rear-wheel drive vehicles, performs comparably to four-wheel-drive and all-wheel-drive systems and provides up to a 10% savings in fuel economy, Eaton says. The new differential provides instant traction and stability under slippery road conditions and improves driver enjoyment under normal conditions.
Our engineering team is employing all the knowledge we have demonstrated as a global leader in developing electronic and mechanical locking and limited slip differentials for larger rear and four-wheel-drive systems that require added performance and utility, and applying it to the unique requirements of more compact, front-wheel-drive vehicles.
We’re focused on the customers’ most critical issue—smaller packaging. This allows our customers to reduce vehicle weight up to 300 lbs. [136 kg], which translates into improved fuel economy and enhanced performance and safety for the end consumer.—Chris Ostrander, vice president and general manager - Eaton Torque Controls
The new Ultra Posi differential is located inside the transaxle and it receives input from the existing brake, wheel-speed, steering-wheel, throttle, yaw and lateral acceleration sensors to ensure each wheel is receiving sufficient torque. In the event of slippage it instantaneously engages a hydraulic power supply to transfer extra torque to the wheel with the most traction by modulating the differential from fully open to fully locked, and anywhere in between, depending on driving conditions.
Electronic Fuel Vapor Management Valve for Hybrid-Electric Vehicles. The electronic fuel vapor management valve for hybrid-electric vehicles manages fuel vapor pressure contained within the fuel tank, increasing safety and enabling automakers to meet emissions regulations. The new system is expected to be in production vehicles by 2011.
Hybrid-electric vehicles have significantly reduced the time the engine is on, which inhibits the ability to purge fuel vapor stored in the carbon canister. Eaton’s Hybrid Fuel Tank Isolation Valve enables fuel vapor containment within the tank until the engine is available and prevents canister saturation and hydrocarbon leakage. Our Fuel Tank Isolation Valve design allows for quick tank venting, minimizing refueling splash-back caused by high fuel tank pressures.—Julie Tolley, general manager, Fuel Emissions and Powertrain Controls, Eaton’s Vehicle Group
The Fuel Tank Isolation Valve leverages two key Eaton technologies—solenoids and vapor management valves—into a simpler, customizable, smaller and smarter system than traditional venting systems.
Eaton uses an optimized solenoid design and integrates functions to reduce the number of parts required, resulting in a 33% weight savings and a significant reduction in size, said Tolley. The Fuel Tank Isolation Valve also has an available integrated pressure sensor that can be used for fuel system leak detection and purge control.
Next-Generation of Variable Valvetrains. Eaton has developed a range of next-generation variable valvetrain systems for high-speed overhead camshaft engines. The company’s new cylinder deactivation and variable valve lift systems will debut with multiple global automakers over the next three years.
Eaton’s cylinder deactivation system is designed specifically for engines with overhead camshaft valvetrains and works seamlessly with the engine management system to efficiently reduce engine displacement when full power is not needed. The system comprises a deactivation rocker arm and oil control valve. When engine conditions are right, for example in highway cruise, the engine computer gives a command to the oil control valve and the unneeded cylinders shut down to save fuel.
Cylinder deactivation has a proven record in V8 pushrod engines, with millions of vehicles on the road saving fuel. We optimized the system in response to the growing consumer demand for overhead cam, multi-valve engines.—Dave Genise, director of engineering for Eaton’s Valvetrain business
Eaton’s new variable valve lift systems eliminates the trade-off between fuel economy and power by providing the ability to switch valve lift profiles to deliver both when required. The system can provide a fuel economy benefit of up to 7% when combined with existing cam phaser technology, Eaton said. The variable valve lift system switches modes in the same manner as the cylinder deactivation rocker arm and can be designed as interchangeable to enable the manufacturers maximum flexibility to utilize a family of engines in diverse markets by changing the valvetrain components.
New Engine Valves. Eaton said that a series of process improvements and new engine valve product designs will help engine manufacturers address issues related to engine downsizing to achieve better fuel economy and reduced emissions.
The pursuit of fuel efficient vehicles is driving the development of smaller engines with a greater power density which puts more stress on the internal components like the intake and exhaust valves. To address this trend and help our customers to achieve their fuel economy and emissions goals, we’re developing new alloys, manufacturing processes and original valve designs to meet their needs.—Dave Genise
When alloy choice alone is not enough to handle thermal loads, Eaton offers a full range of internally cooled engine valves. Commonly found in aircraft valves through the years, internally cooled, or sodium-cooled valves are effective at reducing valve temperatures but a new approach was needed to be a viable option for high volume automotive engines.
To meet this need, Eaton developed a new laser welding process, which facilitates high volume manufacture of internally cooled valves with conventional equipment. The new valve design is not limited by size or stem diameter considerations, and offers up to 50% reduction in weight and up to a 65 °C decrease in valve operating temperatures, permitting the use of standard valve materials.
Supercharger Technologies. Eaton has won four new programs this year because of the advancements in overall performance and value of its superchargers, said Darryl Niven, general manager, Eaton Supercharger Division.
Recent examples of the trend toward supercharging include:
Nissan recently announced its 2011 1.2L, 3-cylinder Micra city car will be powered an engine with Eaton’s most advanced supercharger, the Twin Vortices Series (TVS). Nissan says the engine is aiming to achieve the lowest level of fuel consumption in the world for a gasoline-powered engine, and offers the engine power output equivalent to a 1.5L engine.
China’s largest independent automaker, Chery Automobile Co. Ltd., will debut the first use of Eaton superchargers in China on three vehicles, the 2010 1.6S Tiggo, 1.3S A3 and Riich 1.3S G3.
Volkswagen’s 2010 1.4L TSI Twincharger four-cylinder engine combines a supercharger with turbocharging, and won the International Engine of the Year Award for the second consecutive year. The engine is used in more than eight Volkswagen models.
The 2010 Porsche Cayenne S Hybrid SUV features an Audi 3.0L V6 direct fuel- injection engine with Eaton’s TVS supercharger that produces 20% less carbon dioxide emissions compared to gas-only systems and achieves 26 mpg.
The 2010 Volkswagen Touareg Hybrid features a supercharged 3.0L TSI V6 engine that is shared with the automaker’s Audi brand and matched with a new 8-speed automatic transmission and an electric-hybrid system to provide 17 to 25 percent better fuel economy than a conventional Touareg.
Audi will replace the 3.6-liter V-6 and the 4.2-liter V-8, in favor of two versions of the company’s relatively new 3.0-liter supercharged V-6 on its 2011 Q7 sport utility vehicle (SUV). The new supercharged V6 will provide 17 to 24% better fuel economy than the current 3.6L V6 and 4.2L V8 engines.
The original Eaton supercharger design is a Roots-type positive displacement supercharger that features twin three-lobe rotors that are twisted 60-degrees. The intermeshing, high-speed rotor design pumps air directly into the engines intake system that when mixed with fuel creates more power instantly and without the lag that is common with turbo charging.
The Eaton TVS supercharger is also a Roots-type positive displacement device but it has twin four-lobe rotors that are twisted 160-degrees. The fourth lobe and added twist, when combined with redesigned air inlet and outlet ports, creates a smooth, highly efficient flow of air into the engine and has improved noise and vibration characteristics.
Eaton superchargers perform well with all engine types, including diesel, which produce cooler exhaust temperatures that can limit the efficiency of turbochargers. Supercharged engines can also provide up to a 50% reduction in emissions during acceleration and deceleration events when compared to a non-supercharged engine creating the same amount of power, Eaton said.
Eaton superchargers also lower emissions on cold starts and for start/stop hybrid motors; because they are relatively compact they can be placed anywhere near the engine.