Demand For Increased Fuel Economy Drives Eaton to Develop New Automotive Technology
As the global focus on improving fuel economy reaches a new level, the writing on the wall has become clear to automakers and those who supply them. Consumers are demanding more efficient and, in many cases, smaller vehicles and governments worldwide are putting new emphasis on reducing emissions… and Eaton Corporation, being one of the largest, oldest and most diverse automotive suppliers in the world, has noticed the shift. At an event last week outside of Detroit, Michigan, Eaton took the time showcase just how much the rapidly changing landscape of the automotive industry is shaping their current and future direction.
After spending an entire day at the Eaton proving grounds learning about, and, in some cases, trying out these new technologies, what is clear to me is that not only has Eaton recognized the scope of the changing landscape, they have grasped a fundamental aspect of it that appears to have shaped their overarching design philosophy. Namely, consumers and regulators want more efficient vehicles, but they don’t want to give up any of the increased safety and convenience features we’ve all come to rely on. Although this seems like a rather simple concept, squeezing more fuel economy (or electric range) out of cars that are loaded with airbags, ABS, traction control, horsepower, GPS, computers, et al., is going to become one of the defining challenges of all automakers in the next two decades.
So what technologies has Eaton been working on to meet these challenges?
Performance and Improved Fuel Economy in a Smaller, Less-Expensive Package
Eaton’s been in the supercharger business for some time now, having put their first production supercharger into the 1988 Ford Thunderbird Supercoupe. In the past, the turbocharging and supercharging arena has been devoted to making cars more powerful and better performing, but recently the trend has been to use the two similar, but different technologies to make smaller displacement engines maintain their fuel economy but perform as if they were larger displacement.
“Performance is our history, we know how to make horsepower,” said Dan Ouwenga, a senior engineer in the Eaton supercharger group. “But now our focus is on supercharging for fuel economy and emissions.” Although many manufacturers have chosen to go with turbo charging systems to attain increased performance from smaller, more fuel efficient engines, Eaton has pursued the supercharger because it is a less-expensive and less complicated avenue to the same results—and automakers are taking notice.
This year alone, Eaton has won four contracts to supply supercharging components, adding to their ever-increasing supercharger client list, including Nissan, Chery, Porsche, Volkswagen, and Audi. Nissan’s recently announced 1.2 liter, 3-cylinder Micra minicar sports the Eaton Twin Vortices Series (TVS) supercharger to make its itty-bitty engine perform like a larger 1.5 liter, 4-cylinder engine. Audi will also be using Eaton superchargers across an increasing swath of their lineup in order to downsize engines, increase fuel economy by about 20% and maintain the performance characteristics of the larger engines.
Improved Traction Control
Most of the Benefits of All-Wheel Drive in a Light Two Wheel Drive System
Of all the technologies I had a chance to test out at the Eaton drive event, the one that most impressed me was their new limited slip differential system known as “Ultra-posi.” This technology is so new, that Eaton doesn’t even have any buyers for it yet, but based on my experience, it won’t be long before it becomes a hot commodity. Why you ask? Simple, it provides the performance and benefits of an all-wheel drive system in a two-wheel drive package. It may sound strange, but when I drove it up a steep incline where one wheel was on ball bearings and the other on solid ground, the difference between the Ultra-posi being engaged and not engaged was the difference between being stuck on that slope and making it all the way to the top.
The Ultra-posi system can be used in either front wheel drive or rear-wheel drive vehicles and works by managing a nearly infinitely dynamic torque transition from the drive wheel that is slipping to the wheel that isn’t (or slipping less). What’s amazing about the system is that is is virtually the same weight as a traditional differential (less than 10′s of pounds), meaning that consumers who want the benefits of AWD could get it in a package that doesn’t compromise fuel economy. Also, according to Jeff Saxton, an Eaton senior product engineer, the addition of an Ultra-posi system to a vehicle would only cost an extra $250 or so, which, when compared to the thousands that an AWD system adds to vehicle, sounds like a steal. Contat also said that the system is production-ready at this point, and it will simply take a manufacturer that wants to add it as an option before it’s available to the mass market.
Better Valves and Valvetrain Components
New Manufacturing Methods and Unique Components Make it Easy For Manufacturers to Improve Fuel Economy
As engines get smaller, yet maintain the power density of a larger engine, the valves in them tend to take a greater beating. In these extreme engine environments, traditional valve materials can’t stand up to the punishment. Unfortunately, the valve materials—so called “exotics”—that do make the grade tend to be extremely pricey and can add significantly to the price of a vehicle.
“This drastic increase in power density has really pushed the capability of valves over time,” said Sandy Schaefer, Eaton valvetrain engineering manager. “Cylinder temperatures are up and the demands on the valves are up, but the ‘exotics’ are out of the price range for conventional vehicles.” One technology that doesn’t rely on using exotic alloys to overcome the issue involves hollowing out the center of the valve stems and then filling them with sodium. The sodium helps to transfer the excess heat of the small, power dense engines away from the valves, increasing engine efficiency and durability. Sodium infill valves are not a new concept, but in the past they have been extremely costly to build. To get around this problem, Eaton has engineered a completely new way of building them that reduces cost and makes them accessible to conventional vehicle pricing.
“We now have a high volume process for manufacturing sodium fill valves,” said Schaefer. “We drill the holes, fill them with sodium and seal them all in one step.” According to Schaefer, the one step process takes about the same time as a manufacturing a traditional valve and, therefore, can be fit into a conventional workflow.
In addition to the new valve manufacturing process, Eaton has designed new rocker arm for overhead camshaft valvetrains that is an off the shelf solution to deactivating unneeded cylinders when cars are traveling at steady speeds. Again, this kind of technology is not new, but Eaton’s new system can be incorporated into an engine without need for much reengineering. “Cylinder deactivation has a proven record in V8 pushrod engines, with millions of vehicles on the road saving fuel,” said Dave Genise, director of engineering for Eaton’s Valvetrain business. “We optimized the system in response to the growing consumer demand for overhead cam, multi-valve engines.” According to Genise, however, the new trend is in turning V6 engines into 4-cylinder engines at cruising speed—in alignment with overall industry trends towards downsizing.
Hybrid Car Fuel Vapor Management
Making Pressurized Fuel Tanks Safer and Minimizing Risk for Extra Pollution
Although Hybrids—both conventional ones like the Prius, and new ones like the Chevy Volt—have done wonders to drive up fuel economy, they have one problem that using less and less fuel and turning on the engine fewer times creates: fuel vapor builds up inside their pressurized tanks and risks being vented to the atmosphere without any pollution control.
“With the proliferation of hybrid vehicles, automakers are researching technologies to improve the performance of fuel systems while meeting safety and emissions regulations,” said Julie Tolley, general manager, Fuel Emissions and Powertrain Controls, Eaton’s Vehicle Group. ”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.”
The Eaton Fuel Tank Isolation Valve is the first in the industry to use both solenoids and vapor management valves. The use of these technologies allows the valve to be simpler, smaller and smarter than traditional venting systems. ”Eaton uses an optimized solenoid design and integrates functions to reduce the number of parts required, resulting in a 33 percent 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. Optional temperature sensing can be added for additional system monitoring and control. In addition, it provides flexible mounting and porting options, configurable electrical connections and variable pressure and flow settings that allow the system to be customized to meet the challenging demands of any auto manufacturer’s specific hybrid packaging requirements.”