June 21, 2002
Ford demonstrates new hydraulic power assist technology
Fontana, California – Ford Motor Company is developing a Hydraulic Power Assist (HPA) technology that may help tomorrow’s trucks be up to one-third more fuel efficient in stop-and-go driving than they are today.
Ford demonstrated the HPA system on a Lincoln Navigator at FutureTruck ’02, a competition involving 15 North American university teams working to develop practical means of integrating breakthrough technologies like fuel cells and hybrid electric powertrains on sport utility vehicles of the future.
The Ford HPA system will reduce fuel consumption while increasing vehicle performance. A reversible hydraulic motor and an energy-storage accumulator recover energy normally lost during braking – storing it as hydraulic pressure to be later released to provide a boost for acceleration. Launching a heavy vehicle from a stop requires much more energy than keeping that vehicle in motion. Adding a hydraulic boost allows the vehicle to accelerate much more quickly than the same truck without it, while greatly decreasing fuel consumption and exhaust emissions.
Ford first showcased HPA in a concept truck, the Mighty F350 Tonka, at the North American International Auto Show in January.
Ford research indicates that the installation of a HPA system on a medium-duty truck could increase fuel efficiency in stop-and-go driving by 30 to 35 percent and cut exhaust emissions by at least 20 percent.
“America needs large commercial trucks,” said Leo Shedden, director – Ford Truck Programs. “They perform many essential services, especially in our cities. But we need to find ways to make large vehicles more fuel efficient and environmentally compatible. HPA holds the promise to efficiently power these trucks without compromising their utility and performance.”
HPA could be used in commercial trucks and vans operating in stop-and-go duty cycles – such as delivery trucks and airport shuttle vans. These fleet vehicles would be ideal because their drive cycles would result in a rapid payback in operator fuel savings.
The installation of HPA could allow for smaller, more fuel-efficient engines in commercial vehicles – since less engine horsepower and torque would be required to move the vehicle from a stop or in hill-climbing. The Lincoln Navigator research vehicle with HPA features a 4.0-liter V8 Jaguar engine developing 290 hp at 6,100 rpm and a peak of 290 lbs-ft. of torque at 4,250 rpm. Designed for the 4,000-lb. Jaguar XJR, the engine needs the torque boost from HPA at low engine speeds to competitively accelerate the 6,000-lb. Navigator from a stop.
The Ford HPA system demonstrated on this research vehicle provides up to 600 lbs-ft of torque up to 2,000 rpm (drive shaft speed). Navigator’s standard engine is a 5.4-liter 32-valve V8 that develops 300 hp at 5,000 rpm and a peak of 355 lbs-ft. of torque at 2,750 rpm.