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US 8,261,893 B2Granted
Suspension damper having inertia valve and user adjustable pressure-relief
AssigneeFox Factory, Inc.
InventorsWilliam Becker, Robert C. Fox, Dennis K. Wootten
Life of this patent
Estimating the term…
Abstract
A modern suspension damper, for example, a shock absorber or a suspension fork, including an inertia valve and a pressure-relief feature is disclosed. The pressure-relief feature includes a rotatable adjustment knob that allows the pressure-relief threshold to be externally adjusted by the rider “on-the-fly” and without the use of tools.
Claims10
A suspension damper operable between a compressed position and an extended position, comprising:
- a compression chamber having a volume reducing in response to operation of the suspension damper from the extended position to the compressed position;
- a rebound chamber having a volume reducing in response to operation of the suspension damper from the compressed position to the extended position;
- a reservoir chamber;
- damping fluid for flowing between the chambers and gas disposed in the reservoir chamber;
- an inertia valve, including a valve member comprising a substantial inertia mass and being slideably mounted and moveable relative to a first fluid path, at least substantially closing the first fluid path between the compression and reservoir chambers when in a closed position and movable to an open position in response to an acceleration of at least a portion of the suspension damper, such acceleration equaling or exceeding a first threshold,
- a blowoff valve at least substantially closing a second fluid path between the compression and reservoir chambers when in a closed position and movable to an open position in response to pressure in the compression chamber equaling or exceeding a second threshold,
- wherein the second threshold is operable so the blowoff valve opens in response to a severe shock and remains closed in response to a mild and medium shock;
- and
- a pressure relief valve at least substantially closing a third fluid path between the compression and reservoir chambers when in a closed position and movable to an open position in response to pressure in the compression chamber equaling or exceeding an externally adjustable third threshold.
6 more elements
A suspension damper operable between a compressed position and an extended position, comprising:
- a compression chamber having a volume reducing in response to operation of the suspension damper from the extended position to the compressed position;
- a rebound chamber having a volume reducing in response to operation of the suspension damper from the compressed position to the extended position;
- a reservoir chamber;
- damping fluid for flowing between the chambers and gas disposed in the reservoir chamber;
- an inertia valve, including a valve member comprising a substantial inertia mass and being slideably mounted and moveable relative to a first fluid path, at least substantially closing the first fluid path between the compression and reservoir chambers when in a closed position and movable to an open position in response to an acceleration of at least a portion of the suspension damper, such acceleration equaling or exceeding a first threshold, wherein the inertia valve comprises:
- an outer flow tube having first and second flow ports formed through a wall thereof;
- an inner flow tube disposed within the outer flow tube so that an annulus is formed therebetween and having a head isolating the first flow port from the annulus;
- the substantial inertia mass made from a high density material, having a recess formed therein, and movable between the open and closed positions, wherein the recess provides fluid communication between the first and second flow ports in the open position;
- a spring biasing the inertia mass toward the closed position;
- a pocket receiving the inertia mass in the open position;
- and
- a check valve allowing flow from the pocket and obstructing flow into the pocket;
- and
- a blowoff valve at least substantially closing a second fluid path between the compression and reservoir chambers when in a closed position and movable to an open position in response to pressure in the compression chamber equaling or exceeding a second threshold,
- wherein the second threshold is operable so the blowoff valve opens in response to a severe shock and remains closed in response to a mild and medium shock.
12 more elements
Dependencies are inferred from the claim text.