The meaning of the abbreviation CVT is Continuously Variable Transmission, and it's a type of single-speed automatic gearbox. The CVT gearbox has been used in a variety of cars, but you'll usually find it fitted to a small car. Its compact size and simplicity of construction means it's more cost-effective to use in a small car than a conventional automatic gearbox. In many ways a CVT gearbox is similar to a regular auto. For starters, there is no clutch pedal in a CVT-equipped car, so you can drive it on an automatic-only UK driving licence.
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The meaning of the abbreviation CVT is Continuously Variable Transmission, and it's a type of single-speed automatic gearbox. The CVT gearbox has been used in a variety of cars, but you'll usually find it fitted to a small car.
Its compact size and simplicity of construction means it's more cost-effective to use in a small car than a conventional automatic gearbox. In many ways a CVT gearbox is similar to a regular auto.
For starters, there is no clutch pedal in a CVT-equipped car, so you can drive it on an automatic-only UK driving licence. You'll also find that if a car is offered with a CVT gearbox, it will be more expensive than the same model with a manual gearbox, just like a regular auto. If you compared them back-to-back, the manual model would have better claimed fuel economy, too. The CVT gearbox, and variations thereof, has been around since the dawn of the motorcar, but it was the introduction of the Variomatic gearbox by Dutch car maker DAF in the s that saw CVT become more commonplace in cars.
A CVT gearbox has a relatively simple arrangement of two cone-shaped pulleys with a V-shaped drive belt connecting them. One pulley is attached to the engine, while the other is joined to the wheels. When you press the accelerator, the engine revs and the cone moves according to the amount of power asked for. The other cone adjusts accordingly so that the drive belt maintains the same tension, and this is what determines how the car accelerates.
As the two cones move independently, that means there are no set gear ratios as you would find in a conventional auto or manual, so a CVT is, in effect, a single-speed unit with infinite gear ratios available.
That also explains why CVT-equipped cars have a familiar high-revving character, because engine revs aren't related to wheel speed. Early CVT-equipped cars, such as those built by Dutch firm DAF, had a familiar whining noise as engine revs soared, but road speed built slowly. Today the latest CVT-equipped cars have plenty of sound proofing to ensure refinement is improved.
Another quirk of the DAF system was that the cars it was fitted to didn't have a reverse gear, instead the CVT box simply worked in reverse, so in theory these cars had a top speed that was achievable going both backwards and forwards.
Technology has progressed so that today the CVT gearbox is a better option than it used to be, both in terms of driving enjoyment and efficiency.
Nissan has developed a CVT gearbox called Xtronic which features 'steps' in its power delivery to make it feel more like a conventional gearbox by 'shifting' through the gears. This has a split power delivery so that the car's engine is either driving the wheels or sending power to the battery.
A CVT gearbox doesn't have many moving parts, so it's relatively reliable. It's also mainly used in low-power applications, so cars running a CVT are usually fairly unstressed. As long as the right fluids are used to lubricate the gearbox, and you stick to a regular maintenance schedule, then a CVT box should be no less reliable than a conventional auto or manual. The only real issue you might have is that the drive belt between the two pulleys can wear out.
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HOW IT WORKS: CVT
Non-synchronous Automatic. Variomatic is the stepless, fully automatic transmission of the Dutch car manufacturer DAF , using a drive belt and two pulleys. It was the first continuously variable transmission CVT as opposed to shifting between separate gears. In theory, this always produces the optimum torque. The variomatic was introduced by DAF in , also putting an automatic gear box in the Netherlands for the first time. The variomatic was introduced on the DAF
While technically the first company to use a continuously variable transmission in an automobile was the British Clyno Engineering in , the concept only got popular in , after DAF introduced the with the wonderful Variomatic which made a small car act very funny. Most of us think trucks when it comes to DAF, but company founder Hub van Doorne turned to cars pretty quickly after he got successful by making trucks and buses that could satisfy the high demand of post-war Europe. He designed the Variomatic transmission which " consists of a "V" shaped drive belt and two pulleys, each of two cones, whose effective diameter can be changed so that the "V" belt runs nearer the spindle or nearer the rim, depending on the separation of the cones. These are synchronized so that the belt always remains at the same optimal tension ", according to its Wikipedia article. Further reading also reveals that " because the system does not have separate gears, but one continuously shifting gear and a separate 'reverse mode' as opposed to a reverse gear , the gear works in reverse as well, giving it the interesting side effect that the can drive backwards as fast as forwards. As a result, in the former Dutch annual backward driving world championship, the DAFs had to be put in a separate competition because no other car could keep up ". There's a fun fact for you!
What is a CVT gearbox?
You may know that Google is tracking you, but most people don't realize the extent of it. Luckily, there are simple steps you can take to dramatically reduce Google's tracking. Completely depends on the driver. The concept says it is a more efficient drivetrain when driven efficiently, but, most do not drive for economy. Be prepared for many contradicting answers on this question, that will move over into manual vs automatic vs CV transmissions.