On the kinematic design of differential devices for full time four–wheel–drive vehicles

Abstract

According to Ackerman's principle, the equations of motion of automotive gear differentials, and coupling theorem, we propose a methodology for the conceptual design of differential devices for full time four–wheel–drive vehicles. Based on this design methodology and the concept of train value equations of planetary gear trains, we derive mathematical expressions of train values for the kinematic design of automotive gear differentials. Then, we present new differential devices for full time four–wheel–drive vehicles. These differential devices, which have three degrees of freedom, have the advantage of preventing power loss of vehicles without any locking devices.