Nissan and JATCO have just announced a new continuously variable transmission that features a wider ratio spread than any previous example of the type. The maximum spread from low to high in the past has been 6:1 but Nissan/JATCO have expanded that range to 7.3:1 facilitating better fuel efficiency. Since this is a friction belt type CVT, expanding the ratio spread can normally be problematic because of the physical limitations of bending the steel belt around the pulleys.

However, the automaker and transmissions builder have developed a novel solution that essentially creates a hybrid transmission. It's not a transmission that transfers electrical and mechanical power, however. Rather, it's a combination belt CVT and conventional geared transmission. A small auxiliary gear-set is added to the CVT to provide extra range to the ratios. In spite of the new hardware, Nissan says this new unit is 10 percent shorter in length and 13 percent lighter than other comparable CVT transmissions.

At this point, Nissan has not announced which vehicles will get the new unit. Check out the official press release after the jump.

[Source: Nissan]


Nissan and JATCO Develop Innovative, Next-Generation CVT

TOKYO (July 22)--Nissan Motor Co., Ltd., a long-time leader in the development and application of CVT (Continuously Variable Transmission) technology, and its affiliate transmission supplier JATCO Ltd. today announced the joint development of a new generation of compact and lightweight CVTs.
Next-generation CVT

Next-generation CVT

The next-generation CVT design features an innovative structure combining conventional CVT belt operation with an auxiliary gearbox and a significantly increased gear ratio range. The new CVT is scheduled to appear in compact Nissan vehicles worldwide in the near future.

Major features of the new CVT are:

* World's highest transmission ratio for quicker starts and acceleration
The new structure raises the available transmission ratio from current 6.0:1 to 7.3:1, more than 20 percent higher than other CVTs, for enhanced responsiveness on starting and acceleration. The 7.3:1 ratio is higher than the average conventional 7-speed automatic transmissions used on high-displacement engine-equipped vehicles, making it among the world's highest ratios for production vehicle use*.
* Compact and lightweight
This revolutionary CVT configuration combines a belt-operated CVT with an auxiliary transmission, shortening its overall length by 10 percent and reducing weight by 13 percent compared to conventional CVTs in its class.
* Superb drivability
The next-generation CVT features the Adaptive Shift Control (ASC), which improves performance by automatically selecting the best ratio for startup, acceleration and uphill or downhill driving.

"Nissan believes the CVT has very good potential as a leading technology for raising the fuel efficiency of internal-combustion engine systems," said Shuichi Nishimura, corporate vice president, Nissan Powertrain Engineering Division. "Nissan first began applying CVT technology in 1991 and has been continuously evolving CVTs, engine-cooperative management and other systems, and expanding their use in Nissan vehicles. The need to improve fuel economy, with the resulting reductions in CO2 emissions motivated us to step up our efforts in the joint development with JATCO of this next-generation CVT."

JATCO, the world's leading CVT manufacturer, is the only company that offers a full range of CVTs for applications from mini-vehicles up to 3.5-liter V6-equipped cars. The company produces 43 percent of CVTs made globally.

"The revolutionary structure of the next-generation CVT, with its auxiliary transmission, not only raises the transmission ratio, reduces weight and adds fuel efficiency, its compact design also expands its applicability to a broader range of vehicles," said Yo Usuba, vice president, JATCO. "We believe it is an excellent choice for automakers seeking to raise the fuel efficiency of their smaller cars."

Based on the mid-term environmental program "Nissan Green Program 2010," Nissan and JATCO have achieved sales of 1 million CVT-equipped vehicles, as well as introducing 7-speed automatic transmissions to improve fuel efficiency. The companies will continue to introduce effective technologies and products into the market in pursuit of a sustainable mobility society.

* Excluding DCTs and manual transmissions.