Roll stabilization mechanisms in vehicular suspension systems

• US 6,302,417 B1
• Filed: 04/20/1998
• Issued: 10/16/2001
• Est. Priority Date: 08/21/1995
• Status: Expired due to Term

• Current Assignee: Kinetic Recruitment Services Ltd. (Apollo Global Management, Inc.)
• Original Assignee: Kinetic Recruitment Services Ltd. (Apollo Global Management, Inc.)
• Inventors: Heyring, Christopher B.
• Primary Examiner(s): English, Peter C.
• Application Number:
  US09/029,082
• Time in Patent Office: 1,275 Days
• Field of Search: 280/124.106, 280/124.107, 280/127.137, 280/124.152, 280/124.162, 280/124.166, 267/187, 267/191, 267/190
• US Class Current: 280/124.106
• CPC Class Codes: B60G 21/02 permanently interconnected
• CPC Class Codes: B60G 21/0555 including an actuator inducing vehicle roll
• CPC Class Codes: B60G 21/067 between wheels on different axles on the same side of the vehicle, i.e. the left or the right side

Abstract

A vehicular suspension system for a vehicle includes at least one pair of transversely adjacent front surface engaging members and at least one pair of transversely adjacent back surface engaging members for supporting a body of the vehicle. The suspension system further includes a first force transmitting device interconnecting the at least one pair of transversely adjacent front surface engaging members, and a second force transmitting device interconnecting the at least one pair of transversely adjacent back surface engaging members. The force transmitting devices transfer forces between the interconnected surface engaging members. Each force transmitting device includes an adjustment device for progressively varying the magnitude and direction of the force transferred between the associated surface engaging members by the force transmitting devices as a function of the relative positions of and the load applied to at least two pairs of the interconnected surface engaging members. The adjustment devices are functionally linked such that the magnitude and the direction of the force transmitted between associated surface engaging members by each of the force transmitting devices is progressively varied to thereby maintain and return the attitude of the vehicle to a position that is at least substantially parallel to the average surface plane supporting the vehicle.

Claims

1. A suspension system for a vehicle, said vehicle having a body and at least one forward pair of transversely adjacent surface engaging means and at least one rearward pair of transversely adjacent surface engaging means connected to the body to allow substantially vertical relative motion of each surface engaging means with respect to the body, the suspension system including resilient support means for providing resilient support for substantially the total mass of the vehicle body with respect to the surface engaging means, at least one forward and at least one rearward force transmitting means, each force transmitting means interconnecting at least one of said pairs of transversely adjacent surface engaging means, each force transmitting means including adjustment means, the adjustment means being longitudinally spaced and functionally linked such that the magnitude and the direction of the force transmitted between associated transversely adjacent surface engaging means by each of the force transmitting means varies progressively as a function of the relative positions of, and the load applied to, at least two pairs of the interconnected transversely adjacent surface engaging means, to thereby restrict roll motions of the vehicle whilst simultaneously facilitating warp motions of the surface engaging means.

2. A vehicular suspension system according to claim 1, wherein said resilient support means are provided between each said surface engaging means and the body of the vehicle.

3. A vehicular suspension system according to claim 1, wherein said resilient support means is provided for at least one of said pairs of transversely adjacent surface engaging means for carrying the load applied to both of the associated transversely adjacent surface engaging means.

4. A vehicular suspension system according to claim 1, wherein said resilient support means is provided for said at least one forward pair of transversely adjacent surface engaging means and said resilient support means is provided for said at least one rearward pair of transversely adjacent surface engaging means for respectively providing substantially equal loading on each of the transversely associated surface engaging means.

5. A vehicular suspension system according to claim 1 wherein the force transmitted by the force transmitting means is a torsional force.

6. A vehicular suspension system according to claim 1 wherein said force transmitting means includes at least one transverse torsion bar.

7. A vehicular suspension system according to claim 6, wherein at least one of said force transmitting means includes a first pair of transverse torsion bars, each torsion bar being respectively connected to one of said surface engaging means, the pair of transverse torsion bars being interconnected by the adjustment means.

8. A vehicular suspension system according to claim 7, wherein each torsion bar in the pair of transverse torsion bars has an elongate axis extending in a substantially transverse direction across the vehicle, the torsion bars being rotatable about their elongate axes, the adjustment means progressively controlling the axial rotation of the associated torsion bars relative to each other such that the surface engaging means are permitted to move when undergoing warp motions while the roll attitude of the vehicle is simultaneously restrained by the torsion bars.

9. A vehicular suspension system according to claim 8 wherein each adjustment means provides a mechanical interconnection of an associated pair of torsion bars, and wherein the adjustment means interconnecting said pair of transversely adjacent forward surface engaging means and the adjustment means interconnecting said pair of transversely adjacent rearward surface engaging means are functionally linked by a mechanical connection.

10. A vehicular suspension system according to claim 9 wherein the mechanical connection is a longitudinal shaft interconnecting said adjustment means, each adjustment means including a pair of linkage members respectively connected at one end thereof to one of the torsion bars, the other end of each pair of linkage members being connected to an end of the longitudinal shaft such that torsional forces can be transmitted between said adjustment means.

11. A vehicle suspension system according to claim 7, wherein the adjustment means provides a hydraulically adjustable connection of the torsion bars.

12. A vehicular suspension system according to claim 11, wherein at least one of the adjustment means includes a double-acting ram, the ram having a cylinder and a piston assembly separating the cylinder into two fluid chambers therein, the cylinder being connected to one of the torsion bars, the piston assembly being connected to the other torsion bar, and wherein a fluid communication is provided between said ram and a longitudinally spaced adjustment means.

13. A vehicular suspension system according to claim 12, further comprising a second pair of transverse torsion bars, wherein the fluid communication is provided by a pair of conduit means connecting the two fluid chambers of a double-acting ram within the adjustment means between the first pair of transverse torsion bars, with the fluid chambers of a double-acting ram within the adjustment means between the second pair of transverse torsion bars, whereby the transfer of fluid between the fluid chambers enables relative displacement between each piston assembly and the respectively associated cylinder.

14. A vehicular suspension system according to claim 13, wherein the fluid chambers are connected such that the surface engaging means are permitted to move when undergoing warp motions with the movement of the respective piston assembly within each respective cylinder allowing the transfer of fluid between the connected fluid chambers causing minimal change in the pressure differential across the piston assembly, while roll motions of the vehicle are reacted by an increase in the pressure differential across the piston assemblies generated by the increase in load on the surface engaging means on one side of the vehicle and the similar reduction in the load on the surface engaging means on the other side of the vehicle to thereby control the roll attitude of the vehicle whilst simultaneously minimising the changes in load on each surface engaging means due to warp motions.

15. A vehicular suspension system according to claim 14, further including fluid supply means for supplying fluid to the pair of conduit means so that fluid can be added to a first conduit of said pair of conduit means and fluid can be at least substantially simultaneously removed from a second conduit of said pair of conduit means to thereby enable the roll angle of the vehicle to be controlled either relatively quickly for an active roll control, or relatively slowly for a simple average levelling function.

16. A vehicular suspension system according to claim 15, further including roll resilience means in fluid communication with both of the conduit means.

17. A vehicular suspension system according to claim 16 wherein the roll resilience is controllable by changing the pressure and volume of fluid in the conduit means and the roll resilience means using the fluid supply means.

18. A vehicular suspension system according to claim 13, further including yoke means interconnecting each pair of torsion bars, double-acting support rams interconnecting the yoke means with the body of the vehicle, second conduit means connecting corresponding chambers of the double-acting support rams, and valve means for controlling the fluid flow through each second conduit means to thereby control the pitch motion of the vehicle.

19. A vehicular suspension system according to claim 18, wherein the second conduit means comprises a pair of conduits and further including at least one accumulator in fluid communication with at least one of the conduits in said second conduit means.

20. A vehicular suspension system according to claim 18, further including fluid supply means for supplying and removing fluid from said pair of conduit means.

21. A vehicular suspension system according to claim 7 wherein the adjustment means is a rotary actuation means including a housing supporting a rotor separating the housing into at least two fluid chambers, the housing being connected to one of the torsion bars, the rotor being connected to the other torsion bar.

22. A vehicular suspension system according to claim 21 including conduit means providing fluid communication between the two fluid chambers of the rotary actuation means of the forward torsion bars and the fluid chambers of the rotary actuation means of the rearward torsion bars.

23. A vehicular suspension system according to claim 22 wherein the fluid chambers are connected to thereby progressively vary the relative rotation of the rotor within the housing in each of the linked rotary actuation means such that the surface engaging means are permitted to move when undergoing warp motions with the movement of the rotor within each housing allowing the transfer of fluid between the connected fluid chambers with minimal change in the pressure differential across the rotor, while roll motions of the vehicle are reacted by an increase in the pressure differential across the rotors generated by the increase in load on the surface engaging means on one side of the vehicle and the similar reduction in the load on the surface engaging means on the other side of the vehicle to thereby control the roll attitude of the vehicle whilst simultaneously minimising the changes in load on each surface engaging means due to warp motions.

24. A vehicular suspension system according to claim 7, including a yoke means interconnecting said pair of torsion bars, wherein said resilient support means connects the yoke means to the body of the vehicle, the yoke means transferring the average load carried by the associated surface engaging means to the resilient support means such that the resilient support means at least substantially supports at least a portion of the vehicle to thereby permit the vehicle to maintain an at least substantially uniform load in each surface engaging means regardless of the warp position of the surface engaging means.

25. A vehicular suspension system according to claim 24 wherein the yoke means is provided by a lever arm respectively extending from each torsion bar, the lever arms being interconnected by a cross member arrangement.

26. A vehicular suspension system according to claim 25 wherein the resilient support means interconnects the cross member arrangement with the chassis of the vehicle, the resilient support means including a load support ram having an accumulator in fluid communication with the ram to provide said resilient support.

27. A vehicular suspension system according to claim 6 wherein the force transmitting means includes a single transverse torsion bar and the adjustment means interconnects the torsion bar to at least one of the associated surface engaging means.

28. A-vehicular suspension system according to claim 27 wherein the adjustment means provides a hydraulic connection of the torsion bar to the associated surface engaging means.

29. A vehicular suspension system according to claim 28 wherein each said adjustment means includes a double-acting ram located at one end of the torsion bar, the ram having a cylinder and a piston assembly separating the cylinder into two fluid chambers therein, the cylinder and the piston assembly being connected between one end of the torsion bar and the adjacent surface engaging means.

30. A vehicular suspension system according to claim 29 wherein the rams are in fluid communication and wherein said fluid communication is provided by conduit means respectively connecting the two fluid chambers of the double-acting ram of the forward torsion bar with the fluid chambers of the double-acting ram of the rearward torsion bar.

31. A vehicular suspension system according to claim 30 wherein the fluid chambers are connected such that the surface engaging means are permitted to move when undergoing warp motions with the movement of the piston assembly within each cylinder allowing the transfer of fluid between the connected fluid chambers causing minimal change in the pressure differential across the piston assembly, while roll motions of the vehicle are reacted by an increase in the pressure differential across the piston assemblies generated by the increase in load on the surface engaging means on one side of the vehicle and the similar reduction in the load on the surface engaging means on the other side of the vehicle to thereby control the roll attitude of the vehicle whilst substantially minimising the changes in load on each surface engaging means due to warp motions.

32. A vehicular suspension system according to claim 31 further including fluid supply means for supplying fluid to the conduit means so that fluid can be added to a first conduit and fluid can be at least substantially simultaneously removed from a second conduit to thereby enable the roll angle of the vehicle to be controlled either relatively quickly for an active roll control, or relatively slowly for a simple average levelling function.

33. A vehicular suspension system according to claim 32 further including roll resilience means in fluid communication with both of the conduit means.

34. A vehicular suspension system according to claim 32 wherein the roll resilience is controllable by changing the pressure and volume of fluid in the conduit means and the roll resilience means using the fluid supply means.

35. A vehicular suspension system according to claim 28 wherein the adjustment means is a single-acting ram located at each end of the torsion bars, each ram having a cylinder and a piston assembly supported therein to provide a fluid chamber within the cylinder, the cylinder and piston assembly being connected to one of the torsion bars and the adjacent surface engaging means.

36. A vehicular suspension system according to claim 35 wherein a fluid communication is provided between the rams wherein said fluid communication is provided by conduit means respectively connecting the fluid chamber of each single-acting ram of the forward torsion bar with the fluid chamber of the longitudinally opposing single-acting ram of the rearward torsion bar, the fluid chambers being connected such that the surface engaging means are permitted to move when undergoing warp motions, while roll motions of the vehicle are reacted to by the torsion bars whilst simultaneously minimising the changes in load on each said surface engaging means due to warp motions.

37. A vehicular suspension system according to claim 27 wherein the torsion bar is mechanically coupled to the associated surface engaging means.

38. A vehicular suspension system according to claim 27 wherein said resilient support means are provided between the surface engaging means and the chassis of the vehicle.

39. A vehicle including a suspension system according to claim 1.

40. A suspension system for a vehicle, said vehicle having a body and at least one forward pair of transversely adjacent surface engaging means and at least one rearward pair of transversely adjacent surface engaging means connected to the body to allow substantially vertical relative motion of each surface engaging means with respect to the body;

the suspension system including resilient support means, for supporting the vehicle body with respect to the surface engaging means, said resilient support means being provided for said at least one forward pair of transversely adjacent surface engaging means and for said at least one rearward pair of transversely adjacent surface engaging means for respectively providing substantially equal loading on each of the transversely associated surface engaging means;

at least one forward and at least one rearward force transmitting means, each force transmitting means interconnecting at least one of said pairs of transversely adjacent surface engaging means,

each force transmitting means including adjustment means, the adjustment means being longitudinally spaced and functionally linked such that the magnitude and the direction of the force transmitted between associated transversely adjacent surface engaging means by each of the force transmitting means varies progressively as a function of the relative positions of, and the load applied to, at least two pairs of the interconnected transversely adjacent surface engaging means, to thereby restrict roll motions of the vehicle whilst simultaneously facilitating warp motions of the surface engaging means such that there is negligible change in the load on each said surface engaging means in relatively low speed warp motions.