Patent ID: 6978872

Claim:
A suspension damper comprising: a housing bounding a main chamber; a main piston disposed within the main chamber of the housing, the main piston having a first side and an opposing second side with a compression port extending therebetween; hydraulic fluid disposed within the main chamber; a piston rod having a first end slideably disposed within the main chamber of the housing and an opposing second end disposed outside of the main chamber, the piston rod being selectively movable between an advanced position wherein a portion of the piston rod is advanced into the main chamber causing the fluid pressure of the hydraulic fluid to increase and a retracted position wherein the portion of the piston rod is retracted from the main chamber causing the fluid pressure of the hydraulic fluid to decrease, a portion of the hydraulic fluid passing through the compression port of the main piston as the piston rod is moved between the retracted position and the advanced position; and a control valve assembly disposed within the main chamber adjacent to the main piston, the control valve assembly comprising: a valve guide; and a control valve with at least one of the valve guide or the control valve at least partially encircling the other so that a valve compartment is at least partially formed between the valve guide and the control valve, the valve compartment being sealed from the hydraulic fluid with a gas being disposed within the valve compartment, the control valve assembly being movable between a first position wherein the valve compartment is compressed to a first volume and the control valve is biased against the main piston so as to constrict the passage of the hydraulic fluid through the compression port and a second position wherein the valve compartment is expanded to a second volume larger than the first volume and the control valve is moved away from the main piston so that the hydraulic fluid can more freely flow through the compression port, wherein increasing the fluid pressure of the hydraulic fluid within the main chamber by moving the piston rod from the retracted position to the advanced position acts to move the control valve assembly toward the first position.