MAGNETORHEOLOGICAL FLUID-CONTROLLED VEHICLE SUSPENSION DAMPER

• US 20030102193A1
• Filed: 11/30/2001
• Published: 06/05/2003
• Est. Priority Date: 11/30/2001
• Status: Active Grant

• Current Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Original Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Inventors: Coombs, Joshua D., Osorio, Carlos F., Edmondson, Jeremy R.
• Granted Patent: US 6,681,905 B2
• Time in Patent Office: Days
• US Class Current: 188/267
• CPC Class Codes: B60G 13/001 Arrangements for attachment of dampers mounting arrangements of combined spring and damper units B60G15/00; mountings of fluid dampers in general F16F9/54
• CPC Class Codes: B60G 13/02 having dampers dissipating energy, e.g. frictionally
• CPC Class Codes: B60G 17/0152 characterised by the action on a particular type of suspension unit B60G17/01941 takes precedence
• CPC Class Codes: B60G 17/0157 non-fluid unit, e.g. electric motor
• CPC Class Codes: B60G 2202/22 Rotary Damper
• CPC Class Codes: B60G 2202/25 Dynamic damper
• CPC Class Codes: F16F 9/535 Magnetorheological [MR] fluid dampers springs comprising magnetorheological [MR] elastomers F16F1/361

Abstract

A magnetorheological fluid actuated damper. At least a first and a second cylinder with the first cylinder positioned axially within the second cylinder are provided. A gap is formed between the cylinders. The second cylinder is mounted to a stationary mount of the vehicle chassis and a control arm is mounted at an end of the first cylinder. The first cylinder is mounted on bearings to allow it to rotate relative to the chassis. The gap between the cylinders contains a magnetorheological fluid having an adjustable viscosity in reaction to the application of a magnetic field. A magnetic field is generated over the fluid in the gap.

Claims

1. A magnetorheological fluid actuated damper, said damper comprising:

at least a first and a second concentric cylinder, said first cylinder being positioned axially within said second cylinder, so as to form a gap between said cylinders;

said second cylinder being mounted to a stationary mount of a vehicle chassis;

a control arm mounted at an end of said first cylinder;

said first cylinder being mounted on bearings to allow rotation of said first cylinder relative to said chassis;

said gap between said cylinders containing a magnetorheological fluid having adjustable viscosity in reaction to the application of a magnetic field; and

a magnetic field generated over said fluid in said gap.

2. The magnetorheological fluid actuated damper of claim 1, wherein said second cylinder is unable to rotate.

3. The magnetorheological fluid actuated damper of claim 2, wherein oscillation of said control arm causes said first cylinder to rotate relative to said second cylinder.

4. The magnetorheological fluid actuated damper of claim 3, wherein said magnetic field is generated by a coil.

5. The magnetorheological fluid actuated damper of claim 4, wherein said coil is in contact with at least one of said cylinders and said coil is attached to an electronic circuit allowing variation in current supplied to said coil to adjust the viscosity of said magnetorheological fluid.

6. The magnetorheological fluid actuated damper of claim 5, wherein a second end of said control arm is pivotally mounted to a point on the knuckle of a wheel of said vehicle such that the vertical motion of said wheel causes said control arm to move and rotate said first cylinder relative to said second cylinder.

7. The magnetorheological fluid actuated damper of claim 6, wherein said magnetic coil comprises solenoid windings positioned within said first cylinder.

8. The magnetorheological fluid actuated damper of claim 7, wherein said solenoid windings are connected to an electronic circuit such that said circuit can provide a varying charge to said solenoid windings to create a magnetic field in the vicinity of said solenoid windings.

9. The magnetorheological fluid actuated damper of claim 8, wherein said magnetic field causes an increase in the viscosity of said magnetorheological fluid which in turn increases the amount of force necessary to rotate said first cylinder and relative to said second cylinder.

10. The magnetorheological fluid actuated damper of claim 6, wherein said magnetic coil comprises solenoid windings positioned within said second cylinder.

11. The magnetorheological fluid actuated damper of claim 10, wherein said solenoid windings are connected to an electronic circuit such that said circuit can provide a varying charge to said solenoid windings to create a magnetic field in the vicinity of said solenoid windings.

12. The magnetorheological fluid actuated damper of claim 11, wherein said magnetic field causes an increase in the viscosity of said magnetorheological fluid which in turn increases the amount of force necessary to rotate said first cylinder and therefore decreases the amount of movement of said control arm.

13. The magnetorheological fluid actuated damper of claim 12, wherein said electronic circuit is controlled by an amplifier controlled by a controller that receives feedback from sensors measuring the displacement and velocity of said wheel and the chassis of said vehicle.

14. The magnetorheological fluid actuated damper of claim 13, wherein said damper is mounted on the upper control arm of a double-wishbone suspension system.

15. The magnetorheological fluid actuated damper of claim 13, wherein said damper is mounted on the lower control arm of a double wishbone suspension system.

16. The magnetorheological fluid actuated damper of claim 15, wherein said double wishbone suspension system is a low floor installation.

17. The magnetorheological fluid actuated damper of claim 13, wherein said damper is mounted on the trailing arm of a solid axle suspension system.

18. The magnetorheological fluid actuated damper of claim 13, wherein said damper is mounted to the lower control arm of a strut suspension system.

19. A magnetorheological fluid actuated damper, said damper comprising:

at least a first and a second concentric cylinder, said first cylinder being positioned axially within said second cylinder, so as to form a gap between said cylinders;

said second cylinder being mounted to a stationary mount of a vehicle chassis;

a control arm mounted at an end of said first cylinder;

said first cylinder being mounted on bearings to allow rotation of said first cylinder relative to said chassis;

said gap between said cylinders containing a magnetorheological fluid having adjustable viscosity in reaction to the application of a magnetic field; and

a means for producing a magnetic field over said fluid in said gap.

20. The magnetorheological fluid actuated damper of claim 19, wherein said means for producing a magnetic field is a coil attached to an electronic circuit allowing variation in current supplied to said coil.

21. A magnetorheological fluid actuated damper, said damper comprising:

at least a first and a second concentric cylinder, said first cylinder being positioned axially within said second cylinder, so as to form a gap between said cylinders;

said first cylinder being mounted to a stationary mount of a vehicle chassis;

said second cylinder being mounted on bearings to allow rotation of said second cylinder relative to said chassis;

a control arm mounted on an end of said second cylinder;

said gap between said cylinders containing a magnetorheological fluid having adjustable viscosity in reaction to the application of a magnetic field; and

a magnetic coil in contact with at least one of said cylinders, said coil being attached to an electronic circuit allowing variation in current supplied to said coil to adjust the viscosity of said magnetorheological fluid.

22. A magnetorheological fluid actuated damper, said damper comprising:

at least three concentric cylinders defining gaps therebetween;

a first gap defined between a first and a third cylinder;

a second gap defined between a second cylinder and said third cylinder;

said third cylinder being mounted on bearings to allow rotation of said third cylinder relative to said first and said second cylinders;

said third cylinder being attached to a first end of a control arm at an end of said third cylinder such that the oscillation of said control arm causes said third cylinder to rotate relative to said first and said second cylinders;

said first and said second gaps between said cylinders containing a magnetorheological fluid; and

a coil capable of producing a magnetic field affecting at least one of said gaps to adjust the viscosity of said magnetorheological fluid.

23. The magnetorheological fluid actuated damper of claim 22, wherein said third cylinder is comprised of non-ferrous material.

24. The magnetorheological fluid actuated damper of claim 23, wherein said coil is comprised of solenoid windings.

25. The magnetorheological fluid actuated damper of claim 24, wherein said solenoid windings are within said first cylinder.

26. The magnetorheological fluid actuated damper of claim 24, wherein said solenoid windings are within said second cylinder.

27. The magnetorheological fluid actuated damper of claim 24, wherein said solenoid windings are within said third cylinder.

28. A method for adjustably dampening the suspension system of a vehicle through the use of a magnetorheological fluid actuated barrel damper, said method comprising the steps of:

providing at least a first and a second concentric cylinder, said first cylinder being positioned axially within said second cylinder so as to create a gap between said cylinders;

providing a magnetorheological fluid within said gap;

determining the desired level of dampening;

reading feedback from sensors on the vehicle; and

controlling the viscosity of said magnetorheological fluid through the application of a magnetic field on said magnetorheological fluid such that the resistance to rotation of said rotatable cylinder changes in response to the change in viscosity of said magnetorheological fluid.

29. The method of claim 28, wherein one of said cylinders is attached to the chassis of said vehicle such that said cylinder cannot rotate.

30. The method of claim 29, wherein said other cylinder is attached to a control arm of the suspension system of said vehicle such that said other cylinder can rotate relative to said stationary cylinder in reaction to vertical movement of a wheel of said vehicle.

31. The method of claim 30, wherein said step of applying said magnetic field is accomplished through the provision of an electric charge to a magnetic coil in close proximity to said magnetorheological fluid.

32. The method of claim 31, further comprising the step of adjusting the viscosity of said magnetorheological fluid by varying the electric charge supplied to said magnetic coil.

33. The method of claim 32, wherein increasing the viscosity of said magnetorheological fluid increases the force necessary to rotate said first cylinder.

34. The method of claim 33, wherein decreasing the viscosity of said magnetorheological fluid decreases the force necessary to rotate said first cylinder.

35. The method of claim 34, wherein the step of controlling the viscosity of said magnetorheological fluid is performed by a controller reading feedback from said sensors and activating an amplifier which controls the level of current supplied to said magnetic coil.