Helical Gear Limited Slip Differential with Locking Function

Military off-road vehicles need good passability to adapt to complex road surfaces.The ordinary planetary gear differential has simple structure. Although it can satisfy the requirement that the wheels on both sides move at different speeds when the vehicle is driving, under the condition that the adhesion coefficients on the left and right sides of the road differ greatly, the wheel slipping on the side with small adhesion is easy to occur based on the torque distribution characteristics, which greatly affects the vehicle’s passability.Limited-slip differential overcomes the disadvantage of common differential, which means that most of the torque transferred from engine to drive axle is transmitted to the drive wheel on the side with high adhesion coefficient and improves vehicle passability.

Military off-road vehicles need high off-road performance due to their special attributes of combat tasks.However, in some complex non-structural road conditions, even with limited-slip differential with large locking coefficient, it is difficult to overcome the obstacles and make the vehicle out of trouble.Based on this, a helical gear limited slip differential with locking function is designed on the basis of the limited slip differential of a military off-road vehicle of Dongfeng Mengshi. The helical teeth part of the differential achieves the limited slip function, and the locking part of the differential can automatically achieve the locking function under the limit condition that one side of the wheel loses its adhesion completely.

Off-road performance of military vehicles determines their adaptability under complex battlefield road conditions and is an extremely important indicator.At present, most of the differentials only have a single slip limit function or a single locking function, which is difficult to meet the requirements of military off-road vehicles to adapt to complex road conditions.Through innovative design of differential for military vehicles, this paper establishes a solid model of helical gear limited-slip differential with locking function, which lays a foundation for subsequent simulation research, and aims to provide reference for improvement of differential for military vehicles and improve vehicle passability under extreme conditions.

This design is only a preliminary design for the differential and its locking mechanism. Quantitative analysis on limited slip and locking has not been studied yet. In the follow-up, static, kinematic and dynamic analysis of the model will be carried out to establish a quantitative model of limited slip and locking function of the differential so as to achieve parametric design effect.