Design and Analysis of Lifting Pusher Drop Axle for Heavy Commercial Vehicle

Lifting axles are auxiliary axles that provide increased load carrying capacity in heavy commercial vehicles. Lift axle gives better fuel efficiency as well as it reduces the operational costs by means of increasing the loading carrying capacity. These axles are raised when the vehicle is in unloaded condition, thus increasing the traction on remaining wheels and reducing the tire wear which in turn lower down the maintenance cost of the vehicle. Lifting height and force requires to lift the whole mechanism and are two main considerable factors to design the lifting axle mechanism. Although in India currently, the use of lift mechanism of single tire with continuous axle is more common. But in the case of pusher axle, continuous axle is unable to lift more after certain height because of the draft angle of the propeller shaft, and single tire axle which has less load carrying capacity up to 6T (Tons). Multi-axle vehicles have ‘pusher’ axle that is present in front of the drive tandem axle, which gives additional load carrying capacity for such vehicles. Installing a lifting mechanism in the pusher axle with dual tire and centralized drop axle instead of the continuous axle with using air spring bellows can improve the lifting height without affecting the draft angle of the propeller shaft during the lifting time. Kinematics of lifting mechanism is designed in a way to decrease the lifting force with increase in load carrying capacity of the axle and decrease in packaging value. Dual tire causes less reaction between road and tire due to which tire wear will be reduced. This paper is about to study the whole kinematics; analytical design and to analyze lifting mechanism having 10T dual tire drop axle. © 2017 SAE International.