Twin tube shock with adjustable pressure regulation
A fluid damper having a damper housing with a first and a second fluid volume, and a damping piston located within the damper and separating the first and second fluid volume. The damper piston has a piston fluid pathway formed therethrough and between the first and second fluid volume. The fluid damper includes a fluid accumulator having a pressurizable gas volume and an accumulator fluid volume isolated from one another by a separation member. The fluid damper has a first fluid pathway extending solely between the first fluid volume and the accumulator fluid volume, and the fluid damper has a second fluid pathway extending solely between the second fluid volume and the accumulator fluid volume. A flow control valve is located in at least one of the first and the second fluid pathways, and the flow control valve has a non-zero threshold value.
1 . A fluid damper comprising:
a damper housing having a first fluid volume and a second fluid volume;
a damping piston reciprocatingly disposed within said damper housing separating said first fluid volume from said second fluid volume, said damping piston having damping piston valving coupled thereto;
a piston fluid pathway through said damping piston and said damping piston valving, said piston fluid pathway permitting fluid communication between said first fluid volume and said second fluid volume when a pressure in one of said first fluid volume and the second fluid volume exceeds a threshold value of said damping piston valving;
a fluid accumulator having a pressurizable gas volume and an accumulator fluid volume isolated from one another by a separation member;
a first fluid pathway extending solely between said first fluid volume and said accumulator fluid volume;
a second fluid pathway extending solely between said second fluid volume and said accumulator fluid volume;
a third fluid pathway fluidically coupling said first fluid volume and said second fluid volume to enable fluid flow around said damping piston without passing through said fluid accumulator and without flowing through said piston fluid pathway through said damping piston and said damping piston valving, said third fluid pathway extending between said first fluid volume and said second fluid volume but which does not extend through said fluid accumulator, said third fluid pathway comprising:
an internal bypass fluid path formed within said damper housing; and
internal bypass openings formed in an interior surface of said damper housing, said internal bypass openings fluidly coupled with said internal bypass fluid path;
a first adjustable valve, said first adjustable valve disposed in said first fluid pathway said first adjustable valve having a selectable threshold value which exceeds said threshold value of said damping piston valving, said first adjustable valve including a pressure relief valve, said pressure relief valve of said first adjustable valve disposed to automatically allow fluid flow from said first fluid volume into said accumulator fluid volume when a pressure within said first fluid volume exceeds a first pressure relief valve threshold value, said pressure relief valve of said first adjustable valve for preventing hydrolock of said fluid damper;
a first externally adjustable interface coupled to said first adjustable valve, said first externally adjustable interface configured to enable a user to select between at least two settings for said first adjustable valve;
a second adjustable valve, said second adjustable valve disposed in said second fluid pathway, said second adjustable valve including a pressure relief valve, said pressure relief valve of said second adjustable valve disposed to automatically allow fluid flow from said second fluid volume into said accumulator fluid volume when a pressure within said second fluid volume exceeds a second pressure relief valve threshold value, said pressure relief valve of said second adjustable valve for preventing hydrolock of said fluid damper, such that said fluid damper has two pressure relief valves, said pressure relief valve of said first adjustable valve and said pressure relief valve of said second adjustable valve, for said preventing hydrolock of said fluid damper;
a second externally adjustable interface coupled to said second adjustable valve, said second externally adjustable interface configured to enable said user to select between at least two settings for said second adjustable valve;
wherein adjustments made to said first adjustable valve, via said first externally adjustable interface, do not affect said second fluid pathway through said second adjustable valve;
wherein adjustments made to said second adjustable valve, via said second externally adjustable interface, do not affect said first fluid pathway through said first adjustable valve such that said first adjustable valve and said second adjustable valve are independently adjustable, such that an adjustment to a compression damping characteristic of said fluid damper can be made without affecting a rebound damping characteristic of said fluid damper, and such that an adjustment to said rebound damping characteristic of said fluid damper can be made without affecting said compression damping characteristic of said fluid damper; and
wherein said first externally adjustable interface is operated automatically based upon at least one driving condition of a vehicle to which said damper is coupled, wherein said damping piston valving of said damping piston has a non-maximum compression damping setting, and wherein said damping piston valving of said damping piston does not limit a softness of a soft mode for said fluid damper.
2 . The fluid damper of claim 1 wherein said first fluid volume is a compression chamber of said damper housing and said second fluid volume is a rebound chamber of said damper housing.
3 . The fluid damper of claim 1 wherein said first externally adjustable interface is powered.
4 . The fluid damper of claim 1 wherein said first externally adjustable interface is operable by said user located remotely from said damper.
5 . The fluid damper of claim 1 wherein said second externally adjustable interface is powered.
6 . The fluid damper of claim 1 wherein said second externally adjustable interface is operable by said user located remotely from said damper.
7 . The fluid damper of claim 1 wherein said second externally adjustable interface is operated automatically based upon at least one driving condition of a vehicle to which said damper is coupled.