Suspension unit

A shock absorber unit comprising a housing means defining a cavity therein;

• a spring means;
• a piston means slidable in said housing means;
• first, second and third chamber means;
• a displaceable separation means defining and separating said second and third chamber means, said second chamber means being also delimited by said piston means and defining therein a first orifice means between said piston means and said separation means;
• a second orifice means defined between said first and second chamber means, said first and second chamber means containing a working fluid with said third chamber means comprising a high pressure accumulator;
• an actuating means for positioning a valve means into one of at least a first and a second position thereof, wherein said valve means is adapted in said first position to allow fluid transfer through said second orifice means and in said second position to block said second orifice means, said spring means being adapted for providing a spring force when said piston means is displaced for both the first and second positions of said valve means, whereby in said second position of said valve means, a movement of said piston means forces a transfer of said working fluid within said second chamber means through said first orifice means thereby producing damping, the working fluid between said first orifice means and said separation means exerting a pressure on said separation means the displacement of which being at least partly opposed by said high pressure accumulator thereby providing a supplemental spring force to the spring force of said spring means, whereas in said first position of said valve means, a movement of said piston means forces a transfer of said working fluid through said second orifice means thereby only producing damping.

A shock absorber unit for mounting parallel to a suspension system comprising a housing means defining a cavity therein;

• a piston means slidable in said housing means;
• first, second and third chamber means, said first chamber means comprising a low pressure accumulator and communicating with said second chamber means through a first passage means provided therebetween, said second chamber means being delimited in said housing means by said piston means and by a first orifice means provided between said second and third chamber means, said first and second chamber means containing a working fluid, said third chamber means including a displaceable separation means having on respective sides thereof working fluid for transfer through said first orifice means and a high pressure accumulator;
• an actuating means for positioning a valve means into one of at least a first and a second position thereof, wherein said valve means is adapted in said first position to allow fluid transfer through said first passage means and in said second position to block said first passage means, whereby, in said second position of said valve means, a movement of said piston means forces a transfer of said working fluid from said second to third chamber means through said orifice means thereby producing damping, said working fluid exerting a pressure on said separation means the displacement of which being at least partly opposed by said high pressure accumulator thereby providing a spring force to said shock absorber unit.