Gas spring with travel control

Abstract

In one embodiment, a gas spring having a travel control includes positive and negative chambers and a valve mechanism that controls the fluid communication between the chambers. The valve mechanism includes a valve bore that while only moving a small amount, allows for large changes in gas spring travel length.

1 . A gas spring assembly for a suspension system comprising:
 a tube;   a piston assembly slidably displaceable relative to the tube, the piston assembly separating the tube into a positive spring gas chamber and a negative spring gas chamber; and   a valve mechanism configured to permit gas flow between the positive and negative spring gas chambers when the gas pressure in the negative spring gas chamber exceeds the gas pressure in the positive gas spring chamber.   
     
     
         2 . The gas spring assembly of  claim 1 , wherein the valve mechanism is a one-way valve mechanism permitting gas flow from the negative spring gas chamber to the positive spring gas chamber. 
     
     
         3 . The gas spring assembly of  claim 2 , further including an axial gas passageway extending from the negative spring gas chamber to the positive spring gas chamber, the passageway selectively conducting gas flow through one of a plurality of ports in a wall of the passageway and between the negative and positive spring gas chambers wherein the valve mechanism limits gas flow though the passageway. 
     
     
         4 . The gas spring assembly of  claim 1 , wherein the valve mechanism comprises a valve seat and a valve displaceable toward the valve seat to prevent gas flow between the positive and negative spring gas chambers when the pressure in the positive spring gas chamber exceeds the pressure in the negative spring gas chamber, the valve displaceable away from the valve seat to permit gas flow between the positive and negative spring gas chambers when the pressure in the negative spring gas chamber exceeds the pressure in the positive spring gas chamber. 
     
     
         5 . The gas spring assembly of  claim 1 , wherein the piston assembly comprises a piston slideably displaceable relative to the tube, the piston including a piston rod, the piston having a gas passageway to allow a gas flow between the positive and negative spring gas chambers. 
     
     
         6 . The gas spring assembly of  claim 3 , wherein the valve mechanism further includes a seal disposed between the valve and the valve seat to prevent gas flow between the chambers when the valve is displaced toward the valve seat. 
     
     
         7 . The gas spring assembly of  claim 5 , wherein the seal is an O-ring. 
     
     
         8 . The gas spring assembly of  claim 3 , wherein the valve is an O-ring. 
     
     
         9 . The gas spring assembly of  claim 1 , wherein the piston assembly comprises a piston slideably displaceable relative to the tube and a piston rod operatively connected to the piston, the piston having a gas passageway to allow gas flow between the positive and negative spring gas chambers. 
     
     
         10 . A valve mechanism for a gas spring suspension system having positive and negative spring gas chambers, the valve mechanism comprising:
 a gas passageway extending between the positive and negative spring gas chambers;   a valve seat; and   a valve displaced toward the valve seat to prevent gas flow through the gas passageway when the pressure in the positive spring gas chamber exceeds the pressure in the negative spring gas chamber, the valve displaced away from the valve seat to permit gas flow through the gas passageway when the pressure in the negative spring gas chamber exceeds the pressure in the positive spring gas chamber.   
     
     
         11 . The valve mechanism of  claim 10 , further including a seal disposed between the valve head and the valve seat to prevent gas flow between the positive and negative spring gas chambers when the valve is displaced toward the valve seat. 
     
     
         12 . The valve mechanism of  claim 10 , the gas passageway comprising an axially extending tube having a plurality of orifices through a wall thereof. 
     
     
         13 . The valve mechanism of  claim 11 , wherein the seal is an O-ring. 
     
     
         14 . The valve mechanism of  claim 10 , wherein the valve is an O-ring. 
     
     
         15 . A valve assembly for a suspension system comprising:
 a housing having a plurality of housing fluid flow paths through a housing wall thereof;   a fluid conduit disposed adjacent the housing and having at least one conduit fluid flow path through a conduit wall thereof;   a seal, located between two of the housing fluid flow paths and isolating a surface of the conduit wall from a surface of the housing wall;   a first position wherein the conduit fluid flow path is in fluid communication with a first of the housing fluid flow paths and isolated from a second of the housing fluid flow paths; and   a second position wherein the conduit fluid flow path is in fluid communication with the second of the housing fluid flow paths and isolated from the first of the housing fluid flow paths.   
     
     
         16 . The valve assembly of  claim 15 , further comprising a one way valve blocking fluid flow from entering the fluid conduit. 
     
     
         17 . The valve assembly of  claim 16 , wherein the one way valve comprises a valve member and a valve seat, the valve member biased toward engagement with the valve seat. 
     
     
         18 . The valve assembly of  claim 17 , wherein the valve member comprises an elastomer. 
     
     
         19 . The valve assembly of  claim 18 , further including a seal disposed between the valve member and the valve seat. 
     
     
         20 . The valve assembly of  claim 18 , wherein the valve member is an O-ring. 
     
     
         21 . The valve assembly of  claim 15 , wherein a distance between the first position and the second position is smaller than a distance between the first and second housing fluid flow paths. 
     
     
         22 . The valve assembly of  claim 21 , further comprising a third position wherein the conduit fluid flow path is in fluid communication with a third of the housing fluid flow paths and isolated from the first and second of the housing fluid flow paths. 
     
     
         23 . The valve assembly of  claim 22 , wherein a distance between the third position and the furthest of the first and second positions is less than one half of the distance between the third of the housing fluid flow paths and the furthest of the first and second of the housing fluid flow paths. 
     
     
         24 . A multi-position valve assembly comprising:
 a first tube having an axial fluid flow path through an interior thereof and a first aperture through a first tube wall and in communication with the flow path;   a second tube substantially coaxially disposed relative to the first tube and having a plurality of second apertures through a second tube wall, at least two second apertures being spaced at a first distance apart, the first and the second tubes forming an annulus there between;   a plurality of seals disposed in the annulus, at least one each of the seals being located on each side of each of the second apertures thereby forming a discreet annular chamber for each of the second apertures;   a first position wherein the first aperture is in fluid communication with a first of the chambers and a second position wherein the first aperture is in fluid communication with a second of the chambers and wherein a distance between the first and second positions is less than half of the first distance.   
     
     
         25 . A gas spring suspension system comprising:
 a tube;   a piston assembly disposed within and movable relative to the tube;   a first spring gas chamber and a second spring gas chamber; and   a valve mechanism selectively permitting gas flow between the first and second spring gas chambers.   
     
     
         26 . The gas spring suspension system of  claim 25 , further comprising a damper. 
     
     
         27 . The gas spring suspension system of  claim 26 , wherein the damper comprises a chamber containing a liquid and a damping piston within the chamber. 
     
     
         28 . The gas spring suspension system of  claim 25 , wherein the second spring gas chamber is a negative spring gas chamber. 
     
     
         29 . The gas spring suspension system of  claim 25 , wherein the valve mechanism selectively permits gas flow between the first and second spring gas chambers when the gas pressure in the second spring gas chamber exceeds the gas pressure in the first gas spring chamber. 
     
     
         30 . The gas spring suspension system of  claim 29 , wherein the valve mechanism is operated manually and thereby selectively permits gas flow between the first and second spring gas chambers.