Adjustable gas spring system

1. A spring-damper assembly comprising:

a damper having a cylinder and a piston assembly adapted to move relative to the cylinder; and

an adjustable gas spring system comprising:

a diaphragm extending between a first end and an opposite second end and defining an interior space, the first end of the diaphragm held in a fixed position relative to the cylinder of the damper;

a housing surrounding the diaphragm and coupled to the piston assembly of the damper, the second end of the diaphragm coupled to the housing for movement with the housing relative to the cylinder, the housing configured to provide a sealed environment around the diaphragm for blocking debris from contact with the diaphragm,

a cover coupled to the housing and positioned radially outwardly of the diaphragm, the cover including an opening wherein the cylinder is configured to be positioned within the opening;

a seal member coupled to the cover proximate the opening for movement with the cover relative to the cylinder, wherein the seal member is configured to slide along the cylinder, and

wherein the interior space of the diaphragm is pressurized to bias the second end of the diaphragm away from the first end such that the housing and piston assembly are biased relative to the cylinder toward an extended position.

2. The spring-damper assembly of claim 1 , further comprising a tube coupled to the cylinder of the damper and wherein the first end of the diaphragm is coupled to the tube, and wherein the seal member is configured to form a radial seal against and slide along the tube.

3. The spring-damper assembly of claim 1 , further comprising a plug coupled to the cylinder of the damper and a second seal member coupled to the housing for movement with the housing relative to the cylinder, wherein the first end of the diaphragm is coupled to the plug.

4. The spring-damper assembly of claim 1 , wherein the housing includes a sleeve, the cover coupled to the sleeve, and an endcap coupled to an opposite side of the sleeve from the cover, wherein the piston assembly is coupled to the endcap.

5. The spring-damper assembly of claim 4 , wherein the second end of the diaphragm is coupled to the endcap.

6. The spring-damper assembly of claim 4 , further comprising a fitting coupled to the endcap, wherein the second end of the diaphragm is coupled to the fitting.

7. The spring-damper assembly of claim 1 , wherein the diaphragm is a rolling diaphragm.

8. The spring-damper assembly of claim 7 , wherein the first end of the diaphragm is inverted and extends toward the second end.

9. A vehicle comprising:

a frame;

a suspension coupled to the frame; and

a wheel coupled to the suspension,

wherein a spring-damper assembly is arranged in the suspension, the spring-damper assembly comprising:

a damper having a cylinder and a piston assembly adapted to move relative to the cylinder; and

an adjustable gas spring system comprising:

a diaphragm extending between a first end and an opposite second end and defining an interior space, the first end of the diaphragm held in a fixed position relative to the cylinder of the damper;

a rigid housing surrounding the diaphragm and coupled to the piston assembly of the damper, the second end of the diaphragm coupled to the housing for movement with the housing relative to the cylinder, the housing configured to provide a sealed environment around the diaphragm for blocking debris from contact with the diaphragm;

a cover coupled to the housing and positioned radially outwardly of the diaphragm, the cover including an opening and the cylinder is configured to be positioned within the opening;

a seal member coupled to the cover proximate the opening for movement with the cover relative to the cylinder, wherein the seal member is configured to form a seal with and slide along the cylinder, and

wherein the interior space of the diaphragm is pressurized to bias the second end of the diaphragm away from the first end such that the spring-damper assembly is biased toward an extended position for biasing the wheel relative to the frame.

10. The vehicle of claim 9 , further comprising a tube coupled to the cylinder of the damper wherein the first end of the diaphragm is coupled to the tube, and wherein the seal member is configured to form a radial seal against and slide along the tube.

11. The vehicle of claim 9 , further comprising a plug coupled to the cylinder of the damper and a second seal member coupled to the housing for movement with the housing relative to the cylinder, wherein the first end of the diaphragm is coupled to the plug.

12. The vehicle of claim 9 , wherein the housing includes a sleeve, the cover coupled to the sleeve, and an endcap coupled to an opposite side of the sleeve from the cover, wherein the piston assembly is coupled to the endcap, and wherein the seal member is coupled to the cover for movement with the cover relative to the cylinder.

13. The vehicle of claim 12 , wherein the second end of the diaphragm is coupled to the endcap.

14. The vehicle of claim 12 , further comprising a fitting coupled to the endcap, wherein the second end of the diaphragm is coupled to the fitting.

15. The vehicle of claim 9 , further comprising a first mount arranged on the damper and a second mount arranged on the housing, wherein the first mount is coupled to one of the frame and a control arm of the suspension, and wherein the second mount is coupled to the other one of the frame and the control arm.

16. The vehicle of claim 9 , wherein the diaphragm is a rolling diaphragm.

17. The vehicle of claim 16 , wherein the first end of the diaphragm is inverted and extends toward the second end.

18. An adjustable gas spring system for connection with a damper having a cylinder and a piston assembly adapted to move relative to the cylinder, the adjustable gas spring system comprising:

a diaphragm extending between a first end and an opposite second end and defining an interior space, the first end of the diaphragm arranged to be held in a fixed position relative to the cylinder of the damper;

a rigid housing surrounding the diaphragm and arranged to be coupled to the piston assembly of the damper, the second end of the diaphragm coupled to the housing for movement with the housing relative to the cylinder, the housing configured to provide a sealed environment around the diaphragm for blocking debris from contact with the diaphragm;

a cover coupled to the housing, the cover including an opening that is configured to extend around the cylinder;

a seal member coupled to the cover proximate the opening for movement with the cover relative to the cylinder, wherein the seal member is configured to form a seal with and slide along the cylinder; and

wherein the interior space of the diaphragm is pressurized to bias the second end of the diaphragm away from the first end.

19. The adjustable gas spring system of claim 18 , further comprising a tube adapted to be coupled to the cylinder of the damper, wherein the first end of the diaphragm is coupled to the tube, and wherein the seal member is configured to seal against and slide along the tube.

20. The adjustable gas spring system of claim 18 , wherein the housing includes a sleeve, the cover coupled to the sleeve, and an endcap coupled to an opposite side of the sleeve from the cover, wherein the piston assembly is coupled to the endcap.

21. The adjustable gas spring system of claim 20 , wherein the second end of the diaphragm is coupled to the endcap.

22. The adjustable gas spring system of claim 20 , further comprising a fitting coupled to the endcap, wherein the second end of the diaphragm is coupled to the fitting.

23. The adjustable gas spring system of claim 18 , wherein the diaphragm is a rolling diaphragm.

24. The adjustable gas spring system of claim 23 , wherein the first end of the diaphragm is inverted and extends toward the second end.