by Sean Killcarr
, in Trucks at Work
In the fall this year, Volvo Trucks plans to introduce a new dual clutch configuration for the European version of its I-Shift automated mechanical
transmission (AMT) to prevent speed and torque losses during gear changes.
Volvo added that the I-Shift Dual Clutch will be introduced first on its Volvo FH European highway tractor spec’d with Euro 6-compliant D13 engines rated at 460, 500 and 540 horsepower. Yet there is no date set for when its new AMT configuration will be offered on its heavy Class 8 models here in the U.S.
However, this new version of the I-Shift will no doubt offer yet another significant milepost in the slow yet steady move away from manual gearboxes in the U.S. within the commercial vehicle sector – a shift that’s ramped up particularly fast of late in the medium-duty segment.
“In situations that require a lot of gear changes, for instance on hills or roads with lots of curves and bends, I-Shift Dual Clutch brings an entirely new dimension to truck driving,” noted Claes Nilsson, president Volvo Trucks, in a statement.
“Power-shift gear changes, where there is no interruption in power delivery, means it is easier to keep up with traffic, especially on tricky stretches of roads,” he added. “The result is more relaxed and safe driving.”
Astrid Drewsen, product manager for drivelines at Volvo Trucks, pointed out that the I-Shift Dual Clutch AMT consists of two input shafts and a dual clutch. This means that two gears can be selected at the same time, with the clutch determining which of the gears is currently active. The only time a power loss is experienced with the dual clutch model is during “range-change,” which takes place when shifting from 6th to 7th gear.
And while the I-Shift Dual Clutch is based on Volvo’s existing I-Shift AMT platform, he stressed that the front half of the gearbox has been redesigned with entirely new components. On top of that, the changes only increase the size of the I-Shift Dual Clutch by 4.72 inches when compared to the existing set up.
“When driving it feels like you have access to two gearboxes,” Drewsen explained. “When one gear is selected in one gearbox, the next gear is already prepared in the other. With dual clutches, gear changes take place without any interruption in power delivery. As a result, engine torque is maintained and driving comfort is significantly improved.”
He added that the I-Shift Dual Clutch should be particularly effective in long haul operations as well as conditions that require a lot of gear changing, for instance on hills or on roads with lots of twists and turns, or when driving through cities with plenty of roundabouts and traffic lights.
“I-Shift Dual Clutch also makes a big difference when transporting moving or liquid cargoes, such as animal transports and tanker operations, since the seamless gear changes prompt less movement in the cargo itself,” Drewsen said. “In addition to efficient driving, the smooth gear changes also mean that the in-cab environment feels quieter.”
The proof of the pudding, though, will be when drivers get their hands on them – and that won’t be for a while in the U.S., so we’ll have to see how European big rig operators react to them first.
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