Magneto-rheological dampers for semi-active suspension systems

• US 8,322,497 B2
• Filed: 11/02/2009
• Issued: 12/04/2012
• Est. Priority Date: 05/01/2006
• Status: Active Grant

• Current Assignee: Lord Corporation (Parker-Hannifin Corporation)
• Original Assignee: Lord Corporation (Parker-Hannifin Corporation)
• Inventors: Marjoram, Robert H., Hildebrand, Stephen F., Ivers, Douglas E., Ericksen, Gregory, McMahon, William J., St. Clair, Kenneth A.
• Primary Examiner(s): Rodriguez, Pamela
• Application Number:
  US12/610,648
• Publication Number:
  US 20100096818A1
• Time in Patent Office: 1,128 Days
• Field of Search: 267/64.11, 267/64.15, 267/64.21, 267/64.24, 921/65.R, 921/68, 188/267, 188/267.1, 188/267.2, 188/322.16, 188/322.17
• US Class Current: 188/267
• CPC Class Codes: B60G 2300/07 Off-road vehicles
• CPC Class Codes: B60G 2600/184 Semi-Active control means
• CPC Class Codes: B60G 99/002 Suspension details of the suspension of the vehicle body on the vehicle chassis
• CPC Class Codes: B60G 99/008 Other suspension arrangements with fluid springs
• CPC Class Codes: F16F 13/002 comprising at least one fluid spring F16F13/005, F16F13/02, F16F13/04 take precedence
• CPC Class Codes: F16F 9/064 Units characterised by the location or shape of the expansion chamber F16F9/068, F16F9/08 take precedence
• CPC Class Codes: F16F 9/535 Magnetorheological [MR] fluid dampers springs comprising magnetorheological [MR] elastomers F16F1/361

Abstract

A magneto-rheological fluid damper includes a damper body having a reservoir for a magneto-rheological fluid, a piston rod, a piston rod guide disposed within the damper body, where the piston rod guide has a passage therein for receiving the piston rod. The magneto-rheological fluid damper further includes at least a first piston rod seal and at least a second piston rod seal arranged to seal between the piston rod guide and the piston rod. The magneto-rheological fluid damper further includes a fluid chamber defined between the piston rod guide and the piston rod, the fluid chamber being in communication with the reservoir. The magneto-rheological fluid damper further includes a piston rod guide filter arranged in a communication path between the fluid chamber and the reservoir to filter particulates out of the magneto-rheological fluid entering the fluid chamber. The magneto-rheological fluid damper further includes an accumulator arranged between the piston rod guide and the damper body.

Claims

1. A magneto-rheological damper, comprising:

a damper body having a reservoir for a magneto-rheological fluid;

a piston rod;

a piston rod guide disposed within the damper body, the piston rod guide having a passage therein for receiving the piston rod;

at least a first piston rod seal and at least a second piston rod seal arranged to seal between the piston rod guide and the piston rod;

a fluid chamber defined between the piston rod guide and the piston rod, the fluid chamber being in communication with the reservoir;

a piston rod guide filter arranged in a communication path between the fluid chamber and the reservoir to filter particulates out of the magneto-rheological fluid entering the fluid chamber, wherein the piston rod guide filter includes a magnetic field generator; and

an accumulator arranged between the piston rod guide and the damper body.

2. The magneto-rheological damper of claim 1, further comprising a piston rod bearing assembly coupled to the piston rod guide and arranged to engage and support reciprocal motion of the piston rod.

3. The magneto-rheological damper of claim 1, wherein the accumulator comprises a diaphragm.

4. The magneto-rheological damper of claim 1, wherein the accumulator comprises a gas charged piston.

5. The magneto-rheological damper of claim 1, wherein the magnetic field generator is a permanent magnet.

6. The magneto-rheological damper of claim 1, wherein the magnetic field generator is an electromagnetic coil.

7. The magneto-rheological damper of claim 1, wherein the piston rod guide filter includes a fluid conduit in communication with the reservoir.

8. The magneto-rheological damper of claim 7, wherein the filtering media is disposed in the fluid conduit.

9. The magneto-rheological damper of claim 1, wherein the fluid chamber is defined between the at least first and second piston rod seals.

10. A magneto-rheological damper, comprising:

a damper body having a reservoir for a magneto-rheological fluid;

a piston rod;

a piston rod guide disposed within the damper body, the piston rod guide having a passage therein for receiving the piston rod;

a piston rod bearing assembly coupled to the piston rod guide and arranged to engage and support reciprocal motion of the piston rod;

at least a first piston rod seal and at least a second piston rod seal arranged to seal between the piston rod guide and the piston rod;

a fluid chamber defined between the piston rod guide and the piston rod, the fluid chamber being in communication with the reservoir;

a piston rod guide filter defining a means for filtering fluid entering the fluid chamber, wherein the piston rod guide filter includes a magnetic field generator; and

an accumulator arranged between the piston rod guide and the damper body.

11. The magneto-rheological damper of claim 10, wherein the accumulator comprises a diaphragm.

12. The magneto-rheological damper of claim 10, wherein the accumulator comprises a gas charged piston.

13. The magneto-rheological damper of claim 10, wherein the magnetic field generator is a permanent magnet.

14. The magneto-rheological damper of claim 10, wherein the magnetic field generator is an electromagnetic coil.

15. The magneto-rheological damper of claim 10, wherein the piston rod guide filter includes a fluid conduit in communication with the reservoir.

16. The magneto-rheological damper of claim 15, wherein the filtering media is disposed in the fluid conduit.

17. A method of controlling motion, said method including:

providing a magneto-rheological fluid;

providing a damper body having a reservoir for containing the magneto-rheological fluid;

providing a piston rod;

providing a piston rod guide disposed within the damper body, the piston rod guide having a passage therein for receiving the piston rod;

providing a piston rod assembly coupled to the piston rod guide and arranged to engage and support reciprocal motion of the piston rod;

providing at least a first piston rod seal and at least a second piston rod seal arranged to seal between the piston rod guide and the piston rod;

providing a fluid chamber defined between the piston rod guide and the piston rod;

providing a piston rod guide filter arranged in a communication path between the fluid chamber and the reservoir to filter particulates out of fluid entering the fluid chamber, wherein the piston rod guide filter includes a magnetic field generator; and

providing an accumulator arranged between the piston rod guide and the damper body.

18. A magneto-rheological damper, comprising:

a damper body;

a piston rod guide disposed within the damper body, the piston rod guide having a passage therein for receiving a piston rod;

a piston rod bearing assembly disposed in the piston rod guide to engage with and support reciprocal motion of the piston rod;

at least a first piston rod seal and at least a second piston rod seal arranged to seal between the piston rod guide and the piston rod;

a lubrication chamber defined between the piston rod guide and the piston rod;

a piston rod guide filter, said piston rod guide filter filtering fluid entering the lubrication chamber, wherein said piston rod guide filter includes a magnetic field generator; and

a piston rod guide gas charged accumulator, said piston rod guide gas charged accumulator arranged between the piston rod and the damper body.

19. The magneto-rheological damper of claim 18, wherein the accumulator comprises a diaphragm.

20. The magneto-rheological damper of claim 18, wherein the accumulator comprises an accumulator piston.

21. A land vehicle suspension system fluid damper, comprising:

a damper body;

a piston rod guide disposed within the damper body, the piston rod guide having a passage therein for receiving a piston rod;

a piston rod bearing assembly disposed in the piston rod guide to engage with and support reciprocal motion of the piston rod;

at least a first piston rod seal and at least a second piston rod seal arranged to seal between the piston rod guide and the piston rod;

a lubrication chamber defined between the piston rod guide and the piston rod;

a piston rod guide gas charged accumulator, said piston rod guide gas charged accumulator arranged between the piston rod and the damper body; and

a piston rod guide filter, said piston rod guide filter filtering a plurality of particles entering the lubrication chamber wherein said piston rod guide filter includes a magnetic field generator.

22. The damper of claim 21, wherein the damper includes a magneto-rheological fluid reservoir with a magneto-rheological damper fluid with a plurality of magnetic fluid particles and a filter, said filter filtering said magnetic fluid particles entering the lubrication chamber.