Patent ID: 6520510
Filing Date: 2003-02-18
Classification: B60G

Abstract:
A vehicle roll control system for a vehicle having a pair of wheels each rotatable on an axle, the roll control system comprising:a torsion bar; a hydraulic actuator connected to selectively exert a torque on the torsion bar in a first direction or a second direction opposite the first direction, the hydraulic actuator comprising 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, the cross-sectional area of the first fluid chamber being substantially double the cross-sectional area of the piston rod; a fluid reservoir at essentially atmospheric pressure; a fluid pump providing an activating fluid pressure greater than atmospheric pressure; a directional valve, the directional valve having a first position in which the first fluid chamber and the second fluid chamber are fluidly connected to the pump and a second position in which the second fluid chamber is fluidly connected to the pump and the first fluid chamber is fluidly connected to the fluid reservoir; and control means effective upon detection of a predetermined vehicle condition indicating vehicle roll to activate the fluid pump and the directional valve, the directional valve being activated to its first position when the vehicle roll tends to compress the hydraulic actuator, whereby the activating fluid pressure applied to the first and second fluid chambers tends to extend the hydraulic actuator in opposition to such compression, the directional valve being activated to its second position when the vehicle roll tends to extend the hydraulic actuator, whereby the activating fluid pressure applied to the second fluid chamber relative to the atmospheric pressure applied to the first fluid chamber tends to compress the hydraulic actuator in opposition to such extension.