What Is A CVT?
CVTs are “continuously variable transmissions.” It’s a relatively new type of system that uses pulleys instead of a traditional gearbox to shift gears. To understand how it works, we need to review the purpose of conventional transmissions. During acceleration, your car depends upon horsepower. The transmission’s job is to modify the speed of the engine based upon RPMs in order to maximize that horsepower. It does this through changing gears that interlock with each other.
As the engine’s RPMs climb to a certain level, the transmission shifts gears, reducing them. The problem is that horsepower is most efficient at approximately 5,500 RPMs. When you shift gears, they drop far below that level, effectively making the engine much less efficient.
System Advantages
The main difference about these transmissions is that they don’t use normal interlocking gears to modify the RPMs. Instead, pulleys are used. The benefit of using pulleys is that transmissions are no longer limited to only 4 or 5 gears. They can take advantage of an infinite number of them, delivering the power needed for various driving conditions. Instead of dropping the RPMs to levels at which the engine cannot produce power, a CVT allows your car to continually maintain the RPMs needed. Not only does that provide a smoother ride, but it also promotes better fuel efficiency and quicker acceleration.
Types Of CVTs
There are 3 main types of CVTs that are produced by manufacturers: pulleys, toroidals, and hydrostatics. The most common are those that operate from a pulley system. Though my description about how they work makes them sound complicated, they’re actually simple. Instead of a gearbox, clutch, and interlocking toothed wheels, a pulley-based system uses a belt and 2 pulleys (an input and an output).
Toroidals use discs and power rollers instead of pulleys. Though they look different, they operate under the same principle as pulleys. The third type is called a hydrostatic system, though it’s far less popular than the other 2 options.
Cars With CVTs
Years ago, CVTs were extremely expensive to produce. As a result, few cars had them installed and few people could afford the models that did have them. However, over the past few years, car manufacturers have taken a proactive approach to reducing their production costs. Today, many hybrid cars, such as the Toyota Camry and Nissan Altima, come equipped with them.
There’s little doubt that CVTs are going to eventually become the default transmission installed within most cars. Their inherent benefits are too important to ignore. As technology continues to advance and production costs decline, conventional transmissions will one day disappear.
