According to the required transmission ratio in the working section, the transmission ratio function in the non-working section was constructed by using a polynomial. The linear functional noncircular gear pair, whose transmission ratio is a linear function in the working section, to realize continuously variable transmission was the research object in this paper. Although the characteristics and design methods of noncircular gear pairs have been continuously studied in China, the noncircular gear CVT is still in the preliminary exploration and research stage. The key technology of CVT with noncircular gear has been broken through some countries, and is in the stage of deep application research. The analysis of the system's dynamical response demonstrates that the simulation model established represents the system efficiently.Continuously variable transmission (CVT) of noncircular gear has the technical advantages of large bearing capacity and high transmission efficiency. ![]() The results of the simulation shows that the system becomes steady after a short period of time. The governing differential equations were numerically solved In order to predict the behavior of the different mechanical parts of the system. The kinematical, geometrical and momentum equations governing the performance of the whole system were formulated and solved. In this paper, the slip between the belt and the pulleys and the CVT traction curve were considered. The model takes into consideration each component of the vehicle, including: the engine dry friction disc clutch, belt type CVT, car differential, wheels and body. Aiming at determining the behavior of the CVT transmission, a complete mathematical model have been constructed for the whole vehicle equipped with CVT, simulating the whole vehicle dynamics. The CVT is also fuel efficient, because it reduces the engine speed at high vehicle speed and allows the engine to run at its optimal point. This allows the engine to run at its most efficient RPM independent of the car speed, making CVT the most efficient transmission system. A continuously variable transmission (CVT) provides an infinite number of gear ratios between two finite limits. The underlying theories and mechanisms are also discussed. ![]() This project report evaluates the current state of CVTs and upcoming research and development, set in the context of past development and problems traditionally associated with CVTs. For internal combustion engines this would be 36 percent, while for diesel engines it is 45 percent. This allows the engine to operate at or near its best brake specific fuel consumption rate, which means that the engine is operating at its highest average adiabatic efficiencies. Using a CVT-configured power train, the engine operates at or near maximum load conditions. The operational philosophy of conventional power trains makes it difficult to reach maximum engine fuel efficiency because the opportunities for operating at the lowest fuel consumption or best "brake specific fuel consumption" are restricted and generally do not agree with the torque and speed conditions imposed on the engine by the vehicle. Conventional power train configurations consist of an internal combustion engine operating across a wide range of torque and speed conditions and a transmission that has, by comparison, only a few discrete gear ratios. To achieve gains in this area, we have challenged the conventional thinking associated with power train functions and designs. This stems from the fact that transmissions operate over a range of power conditions, such as low speed-high torque to high speed-low torque, as well as through a variety of gear ratios. ![]() To achieve additional fuel economy improvements, we have begun to focus on increasing efficiency in areas where improvements are much more difficult and costly to achieve-largely on power train components such as the transmission. Unfortunately, improving the variables in that equation is becoming increasingly difficult. One hardly needs to be an automotive engineer to understand that the less fuel an engine consumes, the fewer pollutants produced, and the cleaner the air we breathe.
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