CVT Essay

Trends in Continuously Variable Transmission System: A Literature Review Rushikesh Chaware1, Prof. V. H. Bansode 2
1Department of Mechanical Engineering, Smt. Kashibai Navale College of Engineering, Pune, [e-mail]
2Department of Mechanical Engineering, Smt. Kashibai Navale College of Engineering, Pune, [e-mail]

ABSTRACT
Ample amount of research is going on since last two decades for improving the fuel economy and reduce power loses in vehicle by developing power train systems. Continuously variable transmission (CVT) is a solution for it. The CVT gives the continuously varying gear ratio instead of discrete ratios which saves fuel and gives better performance of vehicle that complies with the engine's working conditions and makes it optimal of the use. Vehicles with CVT gives better

1.(a) Principle of a V-belt CVT; (b) Variator geometry[1]
2. VARIOUS TYPES OF CVT
There are many types of CVTs each with its own unique characteristics, but belt and chain CVTs have gained more importance as they were able to meet the requirements at some context. Following are some types of CVTs.

2.1. Push Belt CVT
Push Belt type of CVT is the most common type. It has a belt composed of segmented steel blocks stacked on a steel ribbon as shown in Fig.3. This belt is used to transmit power between two conical pulleys or sheaves, one fixed and one moving. With this special type of belt it also uses a electronic circuit for continuously changing the distance between the pulleys depending on the engine output which is analogous to the shifting of gears. The advancement in push belt type has been rapid in few years and it has drawn more attention of automakers.

Fig. 2.Model of Push Belt CVT [8] Fig. 3.Composition of Push Belt[8]

2.2. Toroidal Traction-Drive