Patent ID: 7694984
Filing Date: 2010-04-13
Classification: B60G

Abstract:
1. A vehicle roll control system for a vehicle having a pair of front wheels and a pair of rear wheels each rotatable on an axle, comprising a front torsion bar; a front first arm attached to the front torsion bar at one end of the front first arm and being connectable to one of the axles of the front wheels at the other end of the front first arm; a front hydraulic actuator attached to the front torsion bar; a rear torsion bar; a rear first arm attached to the rear torsion bar at one end of the rear first arm and being connectable to one of the axles of the rear wheels at the other end of the rear first arm; a rear hydraulic actuator attached to the rear torsion bar; and control means connected to the front and rear hydraulic actuators and controlling the operation thereof on detection of a predetermined vehicle condition; wherein each front and rear hydraulic actuator comprises a housing, a piston making a sealing sliding fit inside the housing to define a first fluid chamber and a second fluid chamber, and a piston rod connected to the piston and extending through the second fluid chamber and out of the housing; wherein the control means acts on detection of the predetermined vehicle condition to apply a fluid pressure to the first fluid chambers of the front and rear hydraulic actuators and to apply a fluid pressure to the second fluid chambers of the front and rear hydraulic actuators; and wherein the control means comprises a source of fluid pressure, a fluid reservoir, a pressure control valve fluidly connected between the pressure source and the reservoir, a directional valve fluidly connected between the pressure control valve and the hydraulic actuators, and at least two pressure relief valves fluidly connecting the directional valve to the pressure source; wherein the pressure relief valves are actuated to create a pressure differential between one of the first or second fluid chambers of the front and rear hydraulic actuators whilst maintaining the other of the first or second fluid chambers of the front and rear hydraulic actuators at substantially the same pressure.