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US 7,621,382 B2Granted
Shock absorber
AssigneeNissan Technical Center North America, Inc.
InventorDavid T. Zdeb
Life of this patent
Estimating the term…
Abstract
A dampening mechanism is described having 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 is disposed within the pressure tube and divides the working chamber into an upper working chamber and a lower working chamber. A piston rod is secured to the piston. A reservoir tube surrounds the pressure tube defining a reservoir chamber between the reservoir tube and the pressure tube. At least one passage is disposed through the pressure tube between the reservoir chamber and the working chamber and a bypass valve is disposed between the piston and the at least one passage.
Claims19
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.
5 more elements
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 and guided by the rod guide;
- 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
- an elastomeric bypass valve disposed within the pressure tube and between the piston and the rod guide, the bypass valve cooperating with a portion of the valve pressure tube to define a gap between the bypass valve and the pressure tube in an open position whenever the piston is stationary or moving with a velocity less than a predetermined velocity, the bypass valve including a first portion selectively secured to the rod guide and a second portion that pivots between the open position and a closed position when piston is moving the predetermined velocity or faster in each of a direction away from the rod guide and an opposing direction toward the rod guide.
4 more elements
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 and guided by the rod guide;
- 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
- an elastomeric bypass valve disposed between piston and the at least one passage, the bypass valve cooperating with a portion of the pressure tube to define a gap between the bypass valve and the pressure tube in an open position, the bypass valve including a first portion selectively secured to the rod guide and a second portion that pivots between three consecutive positions including the open position and first and second closed positions at opposing pivotal extremes;
- whereby the bypass valve is in the open position resulting from low velocity piston operation and the bypass valve is in the first and second closed positions resulting from high velocity piston operation.
5 more elements
Dependencies are inferred from the claim text.