Load distribution unit for vehicle suspension system

A load distribution unit for a vehicle suspension system having at least one pair of laterally adjacent forward wheel assemblies, and at least one pair of laterally adjacent rear wheel assemblies, a wheel ram associated with each said wheel assembly, each wheel ram including a major chamber therein,

• wherein the load distribution unit includes three fluid chambers aligned along a common axis to thereby provide opposing first and second end chambers and a central chamber therebetween,
• the first and second end chambers being respectively divided by a piston supported therein into two control chambers, the central chamber being divided by two pistons into two control chambers and a central bump chamber,
• respective connection means interconnecting each of the pistons in the central chamber to the piston in an adjacent said end chamber to respectively provide first and second piston assemblies, said respective connection means comprising a rod extending between said first and second end chamber respectively and said central chamber, and contained entirely within said fluid chambers,
• two of the control chambers providing first and second bump chambers, the remaining four control chambers providing system chambers,
• wherein the two system chambers formed by each of the first and second piston assemblies, respectively provide front and rear system chambers respectively connectable to the major chamber of the wheel ram of a said forward wheel assembly, and a said rear wheel assembly on the same side of the vehicle, such that a pressure increase in the major chambers of the wheel rams on one side of the vehicle or a pressure decrease in the major chambers of the wheel rams on one side of the vehicle is reacted by the interconnection means, thereby providing a roll stiffness,
• the central bump volume providing a first bump volume, the first and second bump chambers being in fluid communication to form a second bump volume, such that when the wheel assemblies are undergoing cross-axle articulation motions, the first and second piston assemblies are urged to move in the same axial direction, thereby providing minimal cross-axle articulation stiffness,
• the first and second bump volumes varying in volume proportionately and in opposite senses with relative motion between the first and second piston assemblies, one of said bump volumes providing a front bump volume which varies in volume proportionally and in an opposite sense to the front system chambers, the other said bump volume providing a rear bump volume, to thereby provide a pitch stiffness,
• wherein the front bump volume is in fluid communication with a front bump accumulator means and the rear bump volume is in fluid communication with a rear bump accumulator means.

A load distribution unit for a vehicle suspension system having at least one pair of laterally adjacent forward wheel assemblies, and at least one pair of laterally adjacent rear wheel assemblies, a wheel ram associated with each said wheel assembly, each wheel ram including a major chamber therein,

• wherein the load distribution unit includes a housing divided into a pair of chamber sets, each chamber set including two axially aligned end chambers and a central chamber located and axially aligned therebetween,
• pistons respectively located within the central chamber and within each said end chamber, the pistons being interconnected to thereby provide for common movement of the interconnected pistons within each chamber set, the piston within the central chamber dividing said central chamber into two control chambers, the piston within each said end chamber dividing said end chamber to provide a control chamber on one side thereof, the piston interconnection means comprising a rod contained entirely within said housing,
• two pairs of the control chambers providing bump chambers which vary in volume proportionally and in opposite senses with piston motion, the remaining two pairs of the control chambers providing system chambers,
• a flexible fluid container being located within each said system chamber and being respectively adapted to be in fluid communication with the major chamber of a said wheel ram the interconnected pistons within each chamber set capable of being urged for movement in the same axial direction when the wheel assemblies are undergoing cross-axle articulation motion and capable of being urged for movement in opposing axial directions when the vehicle is undergoing pitch motion to thereby confer minimal articulation stiffness and provide a pitch stiffness which is independent of the roll, four wheel bounce or articulation stiffnesses,
• a flexible fluid container being located within each bump chamber, with fluid communication being provided between the fluid containers in each pair of bump chambers such that the fluid pressure within the communicating bump chambers is transferable therebetween to thereby enable a pressure balance to be achieved between the system chambers,
• wherein each said pair of bump chambers is in fluid communication with a bump accumulator means.