Abstract
KEYWORDS-Automatic Clutch, Idler gear, Epicyclic Gearbox, Sliding Mesh, Transmission System
ABSTRACT –
Passenger cars equipped with manual transmission includes high degree of driving fatigue. This is due to frequent shift of gears according to the road loads. Use of automatic clutch along with intermediate gearbox mainly epicyclic gearbox is an alternative solution but, it increases the overall cost and weight of transmission system. The objective of this study is to design and develop a new, economical and light weight transmission system which can be used with automatic clutch to meet the wide range of tractive effort requirement of the vehicle along with more driving comfort. The operating principle is of sliding mesh type, but unlike conventional sliding mesh gearbox, this transmission eliminates the need of idler gear for reverse drive. The construction of transmission includes four gears mounted on two shafts, primary and secondary shaft. The forward drive is taken from primary shaft by double stage reduction and reverse drive from secondary splined shaft by single stage reduction. Secondary shaft is made in two half, separated by some axial distance. The gear (internally splined) on secondary shaft which will be in mesh while in forward drive will slide over the axial clearance and it will act as a coupler between two half. The variable reduction from automatic clutch along with the constant permanent reduction of transmission system will provide the wide range of tractive requirement. Thus by eliminating idler and other gears, this transmission system is economical, light in weight and it can be used in passenger cars for better driving comfort.