HYDRAULIC TORQUE VECTORING DIFFERENTIAL

摘要

A hydraulic torque vectoring differential includes two epicyclic gear sets and two variable displacement hydrostatic units. Each hydrostatic unit is coupled to a reaction member of one of each of the epicyclic gear sets, each of which also has a first gear element coupled to an input drive shaft for power input from a prime mover of said vehicle and a third gear element coupled to an output shaft operatively driving the wheels of the vehicle. The hydrostatic units are hydraulically coupled so that the hydraulic fluid pressurized in one hydrostatic unit drives the other hydrostatic unit, and fluid pressurized in the other hydrostatic unit drives the one hydrostatic unit. A control system controls the displacement of the variable displacement hydrostatic units. Power from the prime mover flows primarily through the epicyclic gear sets to the output shafts, and only differential power is passed through the hydrostatic units, thereby isolating the hydraulic units from the primary power flow and making use of low displacement hydrostatic units possible for said differential power flow through said differential. The desired torque distribution between the two wheels is determined by existing conventional computer controls based on inputs from known traction sensors.