Suspension system for a vehicle

• US 20030102646A1
• Filed: 01/10/2003
• Published: 06/05/2003
• Est. Priority Date: 12/07/2000
• Status: Active Grant

• Current Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Original Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Inventors: Coombs, Joshua D., Edmondson, Jeremy R., Gloceri, Gary
• Granted Patent: US 6,871,866 B2
• Time in Patent Office: Days
• US Class Current: 280/124.161
• CPC Class Codes: B60G 11/26 having fluid springs only, e.g. hydropneumatic springs B60G11/006, B60G15/12 take precedence
• CPC Class Codes: B60G 11/30 having pressure fluid accumulator therefor, e.g. accumulator arranged in vehicle frame dampers accumulating utilisable energy B60G13/14
• CPC Class Codes: B60G 13/14 having dampers accumulating utilisable energy, e.g. compressing air fluid springs with an accumulator B60G11/30
• CPC Class Codes: B60G 15/06 and fluid damper
• CPC Class Codes: B60G 15/08 having fluid spring
• CPC Class Codes: B60G 15/12 and fluid damper
• CPC Class Codes: B60G 17/033 characterised by regulating means acting on more than one spring
• CPC Class Codes: B60G 17/04 fluid spring characteristics
• CPC Class Codes: B60G 17/0416 regulated by varying the resiliency of hydropneumatic suspensions B60G17/048 takes precedence
• CPC Class Codes: B60G 17/044 Self-pumping fluid springs pumps for liquids F04
• CPC Class Codes: B60G 17/0523 Regulating distributors or valves for pneumatic springs
• CPC Class Codes: B60G 17/056 Regulating distributors or valves for hydropneumatic systemsB60G17/044 - B60G17/048, B60G17/0416 take precedence; Fluid interconnection systems to control vehicle inclination B60G21/06, B60G21/10; valves per se F16K
• CPC Class Codes: B60G 21/0553 adjustable
• CPC Class Codes: B60G 21/073 between wheels on the same axle but on different sides of the vehicle, i.e. the left and right wheel suspensions being interconnected
• CPC Class Codes: B60G 21/10 not permanently interconnected, e.g. operative only on acceleration, only on deceleration or only at off-straight position of steering
• CPC Class Codes: B60G 2202/15 Fluid spring
• CPC Class Codes: B60G 2202/314 The spring being a pneumatic spring
• CPC Class Codes: B60G 2204/80 Interactive suspensions; arrangement affecting more than one suspension unit
• CPC Class Codes: B60G 2204/8304 using a fluid
• CPC Class Codes: B60G 2206/01 Constructional features of suspension elements, e.g. arms, dampers, springs
• CPC Class Codes: B60G 2206/99 : Suspension element selection procedure depending on loading or performance requirements, e.g. selection of damper, spring or bush
• CPC Class Codes: B60G 2500/02 : Supply or exhaust flow rates; Pump operation
• CPC Class Codes: B60G 7/001 : Suspension arms, e.g. constructional features B60G7/006 takes precedence
• CPC Class Codes: F16F 5/00 : Liquid springs in which the liquid works as a spring by compression, e.g. combined with throttling action; Combinations of devices including liquid springs dampers with solid or semi-solid material F16F9/30
• CPC Class Codes: F16F 9/3257 : in twin-tube type devices

Abstract

Suspension system for a vehicle is disclosed and claimed. The suspension system includes a compressible fluid, a suspension strut, a hydraulic cavity, a reservoir, and a volume modulator. The hydraulic cavity is at least partially defined by the suspension strut and is adapted to contain a portion of the compressible fluid. The hydraulic cavity and the compressible fluid supply a suspending spring force that biases a wheel of a vehicle toward the road surface. The volume modulator selectively pushes the compressible fluid into the hydraulic cavity and vents the compressible fluid from the hydraulic cavity, thereby modulating the suspending spring force.

Claims

1. A suspension system for a vehicle having first and second wheels contacting a surface under the vehicle and first and second suspension links respectively suspending the first and second wheels from the vehicle and allowing relative movement of the first and second wheels and the vehicle, said suspension system comprising:

a compressible fluid;

a first suspension strut adapted to couple the first suspension link and the vehicle;

a first hydraulic cavity at least partially defined by said first suspension strut and adapted to contain a portion of said compressible fluid and to cooperate with said compressible fluid to supply a first suspending spring force that biases the first wheel toward the surface;

a second suspension strut adapted to couple the second suspension link and the vehicle;

a second hydraulic cavity at least partially defined by said second suspension strut and adapted to contain a portion of said compressible fluid and to cooperate with said compressible fluid to supply a second suspending spring force that biases the second wheel toward the surface;

a reservoir adapted to contain a portion of said compressible fluid;

a volume modulator coupled to said first and second hydraulic cavities and said reservoir and adapted to selectively push said compressible fluid into said first and second hydraulic cavities and vent said compressible fluid from said first and second hydraulic cavities thereby modulating said first and second suspending spring forces, wherein said volume modulator includes a first cavity-side valve coupled between said first hydraulic cavity and said modulator cavity, a second cavity-side valve coupled between said second hydraulic cavity and said modulator cavity, and a reservoir-side valve coupled between said reservoir and said modulator cavity; and

a control unit coupled to said volume modulator and adapted to influence said volume modulator to push said compressible fluid into said first and second hydraulic cavities to increase the distance between the first and second wheels and the vehicle.

2. The suspension system of claim 1, wherein said control unit is further adapted to control said volume modulator based on the temperature of said compressible fluid.

3. The suspension system of claim 2, wherein said control unit is further adapted to control said volume modulator based on an input from an operator of the vehicle.

4. The suspension system of claim 3, wherein said control unit is further adapted to control said volume modulator based on an input from a road sensor.

5. The suspension system of claim 1, further comprising an anti-roll bar coupled to the first and second suspension links, adapted to selectively connect and restrict movement of the first and second wheels, and adapted to selectively disconnect and allow movement of the first and second wheels.

6. The suspension system of claim 5, wherein said control unit is further adapted to connect said anti-roll bar during a turning maneuver at high speeds to reduce roll of the vehicle.

7. The suspension system of claim 6, wherein said control unit is further adapted to disconnect said anti-roll bar during low speeds to improve ride of the vehicle.

8. The suspension system of claim 7, further comprising a primary cavity-side valve coupled between said modulator cavity and said first and second cavity-side valves.

9. The suspension system of claim 8, wherein said control unit is further adapted to open said primary cavity-side valve, open said first cavity-side valve, open said second cavity-side valve, and close said reservoir-side valve to push said compressible fluid into said first and second hydraulic cavities.

10. The suspension system of claim 9, wherein said control unit is further adapted to open said primary cavity-side valve, open said first cavity-side valve, open said second cavity-side valve, and open said reservoir-side valve to vent said compressible fluid from said first and second hydraulic cavities.

11. The suspension system of claim 10, wherein said control unit is further adapted to close said first cavity-side valve and close said second cavity-side valve during a turning maneuver at high speeds to further reduce roll of the vehicle.

12. The suspension system of claim 10, wherein said control unit is further adapted to close said primary cavity-side valve, open said first cavity-side valve, and open said second cavity-side valve during low speeds to further improve ride of the vehicle.

13. The suspension system of claim 1 wherein said compressible fluid includes a silicone fluid.

14. The suspension system of claim 1 wherein said compressible fluid has a larger compressibility above 2,000 psi than hydraulic oil.

15. The suspension system of claim 1 wherein said compressible fluid is adapted to compress about 1.5% volume at 2,000 psi, about 3% volume at 5,000 psi, and about 6% volume at 10,000 psi.

16. The suspension system of claim 1, further comprising a primary cavity-side valve coupled between said modulator cavity and said first and second cavity-side valves.

17. The suspension system of claim 16, wherein said control unit is further adapted to open said primary cavity-side valve, open said first cavity-side valve, open said second cavity-side valve, and close said reservoir-side valve to push said compressible fluid into said first and second hydraulic cavities.

18. The suspension system of claim 17, wherein said control unit is further adapted to open said primary cavity-side valve, open said first cavity-side valve, open said second cavity-side valve, and open said reservoir-side valve to vent said compressible fluid from said first and second hydraulic cavities.

19. The suspension system of claim 18, wherein said control unit is further adapted to close said first cavity-side valve and close said second cavity-side valve during a turning maneuver at high speeds to reduce roll of the vehicle.

20. The suspension system of claim 18, wherein said control unit is further adapted to close said primary cavity-side valve, open said first cavity-side valve, and open said second cavity-side valve during low speeds to improve ride of the vehicle.