ZF's TraXon transmission with dual clutch.
ALDENHOVEN, GERMANY. Among the many innovations and prototype products ZF Friedrichshafen AG (ZF) displayed this week to industry journalists here at the Aldenhoven Testing Center were its new TraXon transmission, a cab suspension system that smoothes a driver’s ride and a steering system capable of autonomous driving.
All three technologies are part of the company’s Innovation Truck 2014 and will be on display at the upcoming IAA Commercial Vehicle show in Hanover, Germany, Sept. 25 through Oct. 2.
ZF produces individual driveline components including control, actuation, and clutch systems, dual-mass flywheels, PTOs, and retarder systems.
The TraXon is a modular transmission system offered in dual-clutch and hybrid models. It features PreVision GPS, which uses GPS to monitor road grades ahead and adjusts the vehicle’s gear to put it in the proper gear and provide a more fuel efficient ride.
The transmission features two countershafts and one main shaft. It can produce torques considerably above 2,220 lbs-ft. for heavy-duty applications and will be available in 12 or 16 speed, each in either direct drive or overdrive.
New gearing has reduced noise by 6 dB over ZF’s AS Tronic transmission and it has four reverse gears. The TraXon’s modular design allows for five starting or shift modules for maximum flexibility in spec’ing.
A hybrid version will also be available. This model features an electric motor with 120 kW power and a separating clutch enabling all hybrid functions – such as recuperation, electric driving, boosting, and the start-stop function. For special transports, the electric motor can also be used for the power supply of additional units – e.g. for cooling, XF said.
“Studies have shown that the use of hybrid drives in heavy trucks bears considerable savings potential,” said Winfried Gründler, responsible for Truck and Van Driveline Technology at ZF’s Commercial Vehicle Technology division. “It is true that the roughly 5% fuel savings are below the savings that can be achieved in delivery traffic. With the considerably higher mileage and fuel consumption of heavy trucks, hybrid technology is nevertheless an economical solution that goes easy on resources and pays off within a reasonable time period.”
ZF is also introducing a “dual clutch” model. The TraXon Dual allows drivers of long rear axle ratios to upshift or downshift the vehicle while under load under the highest gears without torque interrupt for fuel efficiency.
The TraXon will be available in 2016, although not in the U.S. initially.
Also introduced is a prototype cab suspension system with active roll stabilization. First developed as a joint project with Paccar’s DAF Trucks, the system is designed for driver comfort.
ZF is now developing the system on its own. It features an active roll stabilization system on the front stabilizer. A special control unit, which receives signals on the driving condition from sensors, controls the cabin suspension by means of a hydraulic actuator, the company explained. The respective vehicle conditions are recognized within a split second and the driver’s cabin is then actively stabilized.
It also features the company’s “lightweight design” (LCM), which includes air-spring bellows made out of glass-fiber reinforced plastics (GRP) replacing a conventional steel spring. The GRP spring provides the housing for the hydraulic damper and assumes the function of the outer tube, which is no longer required. As such, a static seal using two O-rings is sufficient for the external seal. The previously required piston rod seal which is subject to wear is also eliminated. The LCM is connected to the vehicle with plastic ring eyes.
Also shown was a new ZF-Servotwin electrohydraulic steering system. According to ZF, the ZF-Servotwin is the world’s first integrated electrohydraulic steering system for heavy commercial vehicles to enter volume production.
The Servotwin is a steering system with “superimposed torque.” The first generation featured speedsensitive steering assistance and an active return to the straight-ahead position.
The target group for the second-generation Servotwin is primarily long-distance heavy commercial vehicles. The steering’s ability to provide automated and semi-automated driving control is a key component of the Innovation Truck, also shown this week.
Corrective steering intervention or a warning signal can also prevent the vehicle from inadvertently wandering out of the lane. All thanks to the lane keeping function.
For stop-and-go driving, the system can maintain proper distance to traffic in front.
In a crosswind situation, the system’s control unit provides the necessary steering correction and initiates it through the electric motor.
The driver can override the system at any time, ZF said.