Independent suspension assembly

1. An independent suspension assembly for a vehicle having a frame and a plurality of wheels, said independent suspension assembly comprising:

a wheel support member, one of the vehicle wheels being mountable on said wheel support member;

an upper control arm, said upper control arm being pivotally secured to said wheel support member at a first location on said upper control arm and pivotally supported relative to the frame at a second location on said upper control arm;

a lower control arm, said lower control arm being pivotally secured to said wheel support member at a first location on said lower control arm and pivotally supported relative to the frame at a second location on said lower control arm;

a linkage member disposed between said lower control arm and the frame, said lower control arm being pivotally secured to said linkage member at a first location on said linkage member and said linkage member being pivotally supported relative to the frame at a second location on said linkage member;

wherein said wheel support member is vertically displaceable relative to the frame by pivotal movement of said upper and lower control arms relative to the frame and to said wheel support member,

a leaf spring assembly having first and second ends and a central area disposed therebetween, each of said first and second ends of said leaf spring assembly being operably coupled with the frame and said central area being operably coupled with said lower control arm, said leaf spring assembly thereby being operably disposed between said lower control arm and the frame wherein a load communicated between said wheel support member and the frame is at least partially transferrable through said leaf spring assembly; and

an air spring assembly operably disposed between said lower control arm and the frame wherein a load communicated between said wheel support member and the frame is at least partially transferrable through said air spring assembly.

2. The independent suspension assembly of claim 1 wherein said linkage member is pivotally secured to the frame at said second linkage member location and wherein said second linkage member location is spaced vertically above said first linkage member location.

3. The independent suspension assembly of claim 2 wherein said linkage member is a substantially V-shaped linkage member having a vertex and first and second arms, said first and second arms defining first and second distal ends opposite said vertex wherein said linkage member is pivotally secured to said lower control arm at said vertex and said linkage member is pivotally secured to the frame at said first and second distal ends.

4. The independent suspension assembly of claim 1 wherein the vehicle defines a longitudinal centerline and said first and second locations on said lower control arm are disposed on opposite sides of the longitudinal centerline.

5. The independent suspension assembly of claim 1 wherein said wheel support member is controllably rotatable about a substantially vertical axis whereby a wheel mounted on said wheel support member is a steerable wheel.

6. The independent suspension assembly of claim l wherein said upper control arm is a substantially V-shaped control arm having a vertex and first and second arms, said first and second arms defining first and second distal ends opposite said vertex wherein said upper control arm is pivotally secured to said wheel support member at said vertex and said upper control arm is pivotally secured to the frame at said first and second distal ends.

7. Au independent suspension assembly for a vehicle having a frame and a plurality of wheels, said independent suspension assembly comprising:

a wheel support member, one of the vehicle wheels being mountable on said wheel support member;

an upper control arm, said upper control arm being pivotally secured to said wheel support member at a first location on said upper control arm and pivotally supported relative to the frame at a second location on said upper control arm;

a lower control arm, said lower control arm being pivotally secured to said wheel support member at a first location on said lower control arm and pivotally supported relative to the frame at a second location on said lower control arm;

wherein said wheel support member is vertically displaceable relative to the frame by pivotal movement of said upper and lower control arms relative to the frame and to said wheel support member; and

a linkage member disposed between said lower control arm and the frame, said lower control arm being pivotally secured to said linkage member wherein said pivotal connection between said lower control arm and said linkage member defines said second lower control arm location and a first location on said linkage member; and wherein said linkage member is pivotally supported relative the frame at a second location on said linkage member.

8. The independent suspension assembly of claim 7 wherein said second linkage member location is spaced vertically above said first linkage member location.

9. The independent suspension assembly of claim 7 wherein said linkage member is a substantially V-shaped linkage member having a vertex and first and second arms, said first and second arms defining first and second distal ends opposite said vertex wherein said linkage member is pivotally secured to said lower control arm at said vertex and said linkage member is pivotally secured to the frame at said first and second distal ends.

10. The independent suspension assembly of claim 7 further comprising:

a leaf spring assembly operably disposed between said lower control arm and the frame wherein a load communicated between said wheel support member and the frame is at least partially transferrable through said leaf spring assembly; and

an air spring assembly operably disposed between said lower control arm and the frame wherein a load communicated between said wheel support member and the frame is at least partially transferrable through said air spring assembly.

11. The independent suspension assembly of claim 7 wherein the vehicle defines a longitudinal centerline and said first and second locations on said lower control arm are disposed on opposite sides of the longitudinal centerline.

12. The independent suspension assembly of claim 7 wherein said wheel support member is controllably rotatable about a substantially vertical axis whereby a wheel mounted on said wheel support member is a steerable wheel.

13. An independent suspension system for a vehicle having a frame and a plurality of wheels wherein the vehicle defines a longitudinal centerline and the plurality of wheels includes paired first and second wheels located on opposite sides of the longitudinal centerline, the first and second wheels being steerable wheels; said independent suspension system comprising:

a first independent suspension assembly for supporting the first wheel and a second independent suspension assembly for supporting the second wheel wherein each of said first and second independent suspension assemblies includes:

a wheel support member, one of the first and second wheels being mountable on said wheel support member, said wheel support member being controllably rotatable about a substantially vertical axis;

an upper control arm, said upper control arm being pivotally secured to said wheel support member at a first location on said upper control arm and pivotally supported relative to the frame at a second location on said upper control arm;

a lower control arm, said lower control arm being pivotally secured to said wheel support member at a first location on said lower control arm and pivotally supported relative to the frame at a second location on said lower control arm;

wherein said wheel support member is vertically displaceable relative to the frame by pivotal movement of said upper and lower control arms relative to the frame and to said wheel support member;

wherein said first and second locations on said lower control arm are disposed on opposite sides of the longitudinal centerline;

a linkage member disposed between said lower control arm and the frame, said lower control arm being pivotally secured to said linkage member at a first location on said linkage member and said linkage member being pivotally supported relative to the frame at a second location on said linkage member; and

a leaf spring assembly having first and second ends and a central area disposed therebetween, each of said first and second ends of said leaf spring assembly being operably coupled with the frame and said central area being operably coupled with said lower control arm, said leaf spring assembly thereby being operably disposed between said lower control arm and the frame wherein a load communicated between said wheel support member and the frame is at least partially transferrable through said leaf spring assembly.

14. The independent suspension system of claim 13 wherein the vehicle includes an engine and wherein at least a portion of each of said lower control arms is disposed below the engine.

15. The independent suspension system of claim 13 wherein each of said first and second suspension assemblies further comprises:

an air spring assembly operably disposed between said lower control arm and the frame wherein a load communicated between said wheel support member and the frame is at least partially transferrable through said air spring assembly.

16. The independent suspension system of claim 13 wherein each of said upper control arms is disposed entirely on one side of the longitudinal centerline.

17. The independent suspension system of claim 13 wherein:

wherein each of said linkage members is respectively pivotally secured to the frame at said second linkage member locations and wherein each of said linkage members is oriented to respectively position said second linkage member locations vertically above said first linkage member locations;

wherein the vehicle includes an engine and at least a portion of each of said lower control arms is disposed below the engine; and

each of said upper control arms is disposed entirely on one side of the longitudinal centerline.

18. The independent suspension system of claim 17 wherein each of said first and second suspension assemblies further comprises:

an air spring assembly operably disposed between said lower control arm and the frame wherein a load communicated between said wheel support member and the frame is at least partially transferrable through said air spring assembly.