solar car Innovation Report

M. M. ENGG. COLLEGE

TEAM MOLTRES ESVC030

INNOVATION Objective: To design such a transmission which is light in weight, compact, easy to use, manually controlled and can transmit power effectively.

therefore called the AR-CVT (Axial Radial CVT). The ratio of the AR-CVT is set by pivoting the arm, which is otherwise stationary with respect to the casing. This results in easy and efficient ratio actuation. A torque on the arm is necessary to keep the arm in position and is related to the tension in the belt. The clamping force on the secondary pulley adapts to the output torque using an innovative high performance torque cam mechanism. It can withstand high axial loads nevertheless it shows very little friction. This enables high efficiency even at partial load, by reducing unnecessary over-clamping. The ratio is set by varying the center distance between the input and output pulley. This way the primary pulley can have a fixed geometry. For the actuation of the primary pulley an innovative device is designed to enable simple actuation with the help of lever.

AXIAL RADIAL CVT A.R CVT is used to change gear manually as per requirement without using clutch. It improve acceleration and efficiency of transmission. Unlike a traditional belt type CVT, in ARCVT one pulley has a fixed running radius i.e. the two conical sheaves of that pulley do not move with respect to each other. The fixed groove pulley moves towards and away from the traditional pulley to achieve this and is therefore called radial pulley. The ‘traditional’ pulley is called the axial pulley because the sheaves only move in axial direction. The proposed CVT concept is

Calculations:Variable pulley diameter = 152 mm (max) to 110 mm (min) Fixed pulley diameter = 75 mm Initial Gear ratio = Final Gear ratio =

=

= 2.02

End Gear ratio =

=

= 1.46

× gear ratio between two gears

So final gear ratio varies from 5.4 to 4.2.

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M. M. ENGG. COLLEGE

TEAM MOLTRES ESVC030

The basic design of AR CVT can be understood by the figure below:-

The prototype of Axial Radial CVT is: -

We are coupling this A.R CVT directly to the wheels. The complete assembly of the system is as below:-

The distance between pivot point and axial pulley, the arm length, the pulley radii and the belt length determine the relationship between arm angle and ratio. The angle at which the arm is located determines the center distance between the two pulleys. Because the belt has a fixed length, the ratio is determined by the angle of the arm. A prototype has been built and experimentally evaluated, showing high efficiency values.

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ADVANTAGE:• • •

Need no clutch to change gear Smooth and continuous gear changing Compact, Less in weight, Low maintenance