Patent ID: 7621382
Filing Date: 2009-11-24
Classification: F16F

Abstract:
1. A dampening mechanism comprising: a pressure tube defining a working chamber between a rod guide proximate a first end and an end cap proximate a second end; a piston disposed within the pressure tube, the piston dividing the working chamber into an upper working chamber and a lower working chamber; a piston rod secured to the piston; a reservoir tube surrounding the pressure tube defining a reservoir chamber between the reservoir tube and the pressure tube; at least one passage disposed through the pressure tube between the reservoir chamber and the working chamber; and a selectively operable bypass valve disposed within the pressure tube and between the piston and the at least one passage, wherein the bypass valve includes a first portion selectively secured to the rod guide and a second portion that pivots about the first portion between an open position and at least one closed position, wherein the bypass valve is in the closed position when a pressure in the working chamber is greater than a pressure in the reservoir tube by at least a threshold amount, the bypass valve is in the closed position when the pressure in the reservoir tube chamber is greater than the pressure in the working chamber by at least the threshold amount, and the bypass valve is in the open position whenever a pressure differential between the working chamber and reservoir tube is less than the threshold amount.