Toyota’s Direct Shift-CVT

Toyota continues to create new technology to make their cars and trucks run better and more efficiently. This is also the case for the new direct shift-CVT, which is a new kind of continuously variable transmission. You’ll see this CVT in the upcoming 2019 Toyota Corolla hatchback and here is a look into how it all works.

What Is a CVT

CVT’s, or continuously variable transmissions, are not new. Many automakers use these instead of a traditional transmission in many of their vehicles because they can be more fuel efficient. A normal CVT uses pulleys and a belt instead of fixed gears to connect the transmission to the wheels. There are fewer working parts with a CVT, and it allows the engine to run using the most efficient RPM’s. The problem is that CVTs can also give drivers a disconnected feel since there is no movement through gears.

The Downside to a CVT

Even though they are more efficient, CVTs are often less responsive when starting from a complete stop, and passing is not always as efficient when traveling at low speeds. Many drivers also miss the feel of the car shifting through the gears. Since a regular CVT’s ratio changes chase the engine speeds instead of the other way around, when you press your foot down on the gas pedal the engine seems to rev out of sync with the car’s acceleration. This is because CVTs work to keep the engine running at the torque’s peak to make it more efficient.

Toyota’s New Direct Shift-CVT

Toyota listened to their drivers and made some exciting changes to their CVT. The new system will use a launch gear to give drivers the feel of a traditional transmission, and it will improve its efficiency in the lower gear ratios. This launch gear is just like the first gear in a regular transmission, and as the vehicle starts to speed up, it switches out and starts working as a normal CVT. By using these fixed ratio gears, the new CVT will improve the belt efficiency and increase the shift speed ratio, resulting in better performance.

The Design

Since the launch gear handles the highest input loads while the car gets up to speed, the equipment in the CVT has much less stress. As a result, the direct shift-CVT will use a narrower belt angle which Toyota reduced from 11 degrees to 9 degrees. This increases the shift speed by 20 percent.
The new system also uses a more compact pulley. Since the launch gears reduce the belt load, a smaller pulley helps to improve the shift responsiveness, and reduced inertia helps to make the shifting more responsive. Because of these design changes, acceleration is more powerful and more rhythmic.
This exciting new CVT design will help to make Toyota vehicles more efficient and more fun to drive. It will come with Toyota’s new 2.0-liter Dynamic four-cylinder engine in the 2019 Toyota Corolla hatchback, and it will hit showroom floors in late July of 2018.

Toyota K CVT transmission. (2022, November 26). In Wikipedia. https://en.wikipedia.org/wiki/Toyota_K_CVT_transmission