Schaeffler Showcases Torque Converter Innovations More Compact, Efficient and Versatile

More compact, lighter and more efficient – these attributes characterize today’s generation of torque converters of the Schaeffler brand LuK. Thus they fully satisfy the requirements of automotive manufacturers and ultimately, of the drivers too. They want to drive environmentally friendly cars; albeit without giving up the comfort they are accustomed too. This is exactly what Schaeffler offers: Vehicle components that help reduce emissions and fuel consumption, whilst increasing the driving comfort and performance.

Taking a look at the new torque converter generation W238 reveals just how much the development has progressed. The key technical data of this generation are: 400 Nm torque and a hydraulic diameter of 238 millimeters. And all of this with a weight of only 14 kilograms and a hydraulic width of just about 5 centimeters. The previous version, W258, weighed in at over 17 kilograms and measured 258 mm in diameter as well as being nearly 70 mm wide. More compact, lighter and yet more efficient – the comparison of these two generations puts it in a nutshell.

Since 1998 Schaeffler has been strengthening its position in the USA by setting up its own torque converter development and production facilities in Wooster/Ohio. The location serves as a center of competence in Schaeffler’s global development network, which comprises 5,500 engineers and technicians.

Continued development work is an important aspect for ensuring the market success of the LuK torque converter. But the company’s innovative strength is just as important. Time and time again, it enables spectacular technology leaps to be achieved. For example, the introduction of the centrifugal pendulum-type absorber virtually revolutionized the field of converter technology. This product has set new standards in the optimization of torque converters. It provides the appropriate answer for automatic transmissions when it comes to the two main trends in engine development: downspeeding and downsizing.

Successfully used in Europe in combination with the dual-mass flywheel, the innovative centrifugal pendulum-type absorber reduces vibration in the drivetrain, thus ensuring lower fuel consumption and emissions as a result of reduced speeds – is now also available for torque converter transmissions. This means the foundations have now been laid for great success in the USA in particular.

The function of the centrifugal pendulum-type absorber is simple: In the new converters, a centrifugal pendulum-type absorber is located on the turbine side of the converter and operated in the oil chamber. A spring damper provides basic isolation of vibrations when the lockup clutch is closed, the remaining irregularities are almost totally canceled out by the centrifugal pendulum-type absorber. The maximum speed fluctuations in the differential input can easily be reduced in this way by more than 70 percent compared to a conventional damper – ideal prerequisites for reducing fuel consumption and CO2 emissions.

Marc McGrath, Head of the Torque Converter Product Line in the USA, is proud of the new product: “The centrifugal pendulum-type absorber sets another milestone in the history of the converter. A reduction in fuel consumption combined with an improvement of driving comfort, where else can you find that? I am sure the North American market will soon recognize the advantages of this converter with centrifugal pendulum-type absorber.”

##IMAGE_3_R##Another converter innovation has been tailored to modern, charged engines and is a revolutionary invention in the field of torque converters: The multi-function torque converter (MFTC) can be ideally combined with start-stop systems and is capable of compensating for the customary delayed response behavior, also known as turbo lag. In addition, the multi-function converter enables a reduction in fuel consumption of up to 5 percent to be achieved, using idle disconnect and the early lock-up of the converter. The disconnection of the transmission and the engine made possible through the MFTC eliminates idle losses of the converter. Moreover this converter configuration allows a more favorable distribution of the mass moments of inertia, which results in excellent vibration isolation in all driving situations. Thanks to this engine disconnection, the engine is able to reach higher start-up speeds as soon as the torque converter is activated. This leads to significant improvements in the launch behavior of turbo-charged vehicles and is a key to overcoming the dreaded turbo lag.

“With the dual-mass flywheel invented by LuK some time ago, we came up with a solution for effectively eliminating vibration in the drivetrain of manual transmission vehicles,” says Norbert Indlekofer, Member of the Schaeffler Executive Board in charge of Transmission Systems. “With the centrifugal pendulum-type absorber and the multi-function torque converter we are now presenting a corresponding solution for vehicles with automatic transmissions. The latest torque converter innovations of the LuK brand impressively document the performance capability of this comfort and performance oriented component at the heart of the advanced automobile.”