Design and analysis of symmetric and asymmetric helical gear mechanisms

Together with the developing technology, it is aimed to design and manufacture mechanisms of smaller size and weight that transmit high torque in power transmission systems. By using asymmetric gears in the same size gear mechanisms with that of symmetric gear, it is possible to obtain higher load-bearing capacity. Beside, asymmetrical gear mechanisms reduce noise and increase efficiency. Gears in most gear wheel mechanisms are not subjected to the equal load in clockwise and anti-clockwise directions. For this reason, the symmetrical structure of the gear is broken and the gear is optimized with asymmetrical form. In this study, the asymmetrical helical gear design for helical gear wheel mechanisms has been developed and compared with the gear design in the mechanisms used the existing symmetrical gear. The load bearing capacity of the gear mechanisms having gears with asymmetrical teeth profile were increased according to that the gear mechanisms of the symmetrical gears having the same material quality of gears. The gear wheel design with the most suitable pressure angle was determined by examining the working condition of the gear wheels designed with different pressure angles. Asymmetric gears in the helical gearwheels was examinated the capacity of reduce the size and weight and increase the load capacity. As a result, asymmetric gear design of the same dimensions with symetric gear was made and an increase in gear strength of 23,43-33,68% was obtained.