GKN Driveline has developed two lightweight, low-friction joints that improve fuel economy, reduce noise and vibration, and make cars easier to park by enabling the driver to turn a tighter circle.
The constant velocity, or CV, joint is the flexible coupling at the end of the driveshaft that connects the wheels to the transmission in front-wheel-drive cars and the transmission to the axle on rear-wheel-drive vehicles.
GKN says the joints are the first major improvements in constant velocity joint technology since the device was patented in the 1930s and used on the radical fwd Cord 810/812, built in 1936 and 1937.
One new joint, called Countertrack, is designed to fit on driveshafts for rwd vehicles, while the other, called Crosstrack, works on the shafts used in fwd and all-wheel-drive vehicles. Both use unique ball bearings and ball bearing tracks to reduce friction.
On a typical mid-sized V-6-powered fwd sedan, a pair of driveshafts fitted with Crosstrack joints will save 8.8 pounds of weight, said Al Deane, GKN's senior vice president of engineering. That weight savings could improve fuel economy by .02 percent, he added.
Because the Countertrack joint is more flexible than a regular constant velocity joint, the turning radius of a mid-sized vehicle is reduced by about 3.2 feet, according to GKN.
GKN Driveline, a unit of Great Britain's GKN PLC, expects to have the Countertrack joint in production in North America on a 2007 model year vehicle, Deane said. GKN has collaboration contracts with four other automakers, two Japanese and two European, and expects them to lead to production contracts once the joints pass rigid testing.
GKN PLC UK ranks No. 23 on the Automotive News list of the top 100 global suppliers with estimated worldwide original-equipment automotive parts sales of $5.61 billion in 2004.
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