Magnetorheological (MR) piston, MR piston assembly, and MR damper system

1. A magnetorheological (MR) piston ( 12 ) comprising:

a) first and second MR piston end plates ( 36 and 38 ) having corresponding first and second orifices ( 44 and 46 );

b) an MR piston core ( 40 ) having a central longitudinal axis ( 16 ) and disposed longitudinally between and attached to the first and second MR piston end plates ( 36 and 38 );

c) an MR piston ring ( 42 ) attached to the first and second MR piston end plates ( 36 and 38 ) and radially spaced apart from the MR piston core ( 40 ) creating a gap ( 48 ) therebetween, wherein the gap ( 48 ) is in fluid communication with the first and second orifices ( 44 and 46 ) to overall define an MR passageway ( 22 );

d) a main electric coil ( 24 ) disposed in the MR piston core ( 40 ) to magnetically energize the gap ( 48 ) of the MR passageway ( 22 ); and

e) an electromagnetic valve ( 26 ) operatively connected to the MR passageway ( 22 ), wherein the electromagnetic valve ( 26 ) has an electromagnetic-valve coil ( 32 ), a spring-loaded restrictor plate ( 50 ), a first state which magnetically attracts the spring-loaded restrictor plate ( 50 ) toward the electromagnetic-valve coil ( 32 ) when the electromagnetic-valve coil ( 32 ) is electrically activated, and a second state which releases the magnetically-attracted spring-loaded restrictor plate ( 50 ) to partially, but not completely, restrict the MR passageway ( 22 ) when the electromagnetic-valve coil ( 32 ) is not electrically activated.

2. The MR piston ( 12 ) of claim 1 , wherein the electromagnetic-valve coil ( 32 ) is attached to the MR piston core ( 40 ).

3. The MR piston ( 12 ) of claim 2 , wherein the spring-loaded restrictor plate ( 50 ) includes a restrictive channel ( 52 ) which is disposed out of fluid communication with the MR passageway ( 22 ) in the first state and which is disposed in fluid communication with the MR passageway ( 22 ) in the second state.

4. The MR piston ( 12 ) of claim 3 , wherein the electromagnetic-valve coil ( 32 ) is substantially coaxially aligned with the central longitudinal axis ( 16 ).

5. The MR piston ( 12 ) of claim 4 , wherein the spring-loaded restrictor plate ( 50 ) is annular and substantially coaxially aligned with the central longitudinal axis ( 16 ).

6. The MR piston ( 12 ) of claim 5 , wherein the spring-loaded restrictor plate ( 50 ) moves substantially parallel to the central longitudinal axis ( 16 ) when the electromagnetic valve ( 26 ) transitions between the first and second states.

7. The MR piston ( 12 ) of claim 6 , wherein the restrictive channel ( 52 ) bends an MR fluid flow ( 54 ) therein substantially ninety degrees.

8. A magnetorheological (MR) damper system ( 60 ) comprising:

a) first and second MR piston end plates ( 36 and 38 ) having corresponding first and second orifices ( 44 and 46 );

b) an MR piston core ( 40 ) having a central longitudinal axis ( 16 ) and disposed longitudinally between and attached to the first and second MR piston end plates ( 36 and 38 );

c) an MR piston ring ( 42 ) attached to the first and second MR piston end plates ( 36 and 38 ) and radially spaced apart from the MR piston core ( 40 ) creating a gap ( 48 ) therebetween, wherein the gap ( 48 ) is in fluid communication with the first and second orifices ( 44 and 46 ) to overall define an MR passageway ( 22 );

d) a main electric coil ( 24 ) disposed in the MR piston core ( 40 ) to magnetically energize the gap ( 48 ) of the MR passageway ( 22 );

e) an electromagnetic valve ( 26 ) operatively connected to the MR passageway ( 22 ), wherein the electromagnetic valve ( 26 ) has an electromagnetic-valve coil ( 32 ), a spring-loaded restrictor plate ( 50 ), a first state which magnetically attracts the spring-loaded restrictor plate ( 50 ) toward the electromagnetic-valve coil ( 32 ) when the electromagnetic-valve coil ( 32 ) is electrically activated, and a second state which releases the magnetically-attracted spring-loaded restrictor plate ( 50 ) to partially, but not completely, restrict the MR passageway ( 22 ) when the electromagnetic-valve coil ( 32 ) is not electrically activated;

f) a rod ( 14 ) attached to at least one of the first MR piston end plate ( 36 ) and the MR piston core ( 40 ) proximate the first MR piston end plate ( 36 );

g) a controller ( 62 ) operatively connectable to an electric power source ( 64 );

h) a first wire ( 28 ) extending from the controller ( 62 ), through the rod ( 14 ), and to the main electric coil ( 24 ); and

i) a second wire ( 30 ) extending from the controller ( 62 ), through the rod ( 14 ), and to the electromagnetic-valve coil ( 32 ).

9. The MR damper system ( 60 ) of claim 8 , wherein the electromagnetic valve ( 26 ) is attached to the MR piston core ( 40 ) proximate the second MR piston end plate ( 38 ).

10. The MR damper system ( 60 ) of claim 9 , wherein the spring-loaded restrictor plate ( 50 ) includes a restrictive channel ( 52 ) which is disposed out of fluid communication with the MR passageway ( 22 ) in the first state and which is disposed in fluid communication with the MR passageway ( 22 ) in the second state.

11. The MR damper system ( 60 ) of claim 10 , wherein the electromagnetic-valve coil ( 32 ) is substantially coaxially aligned with the central longitudinal axis ( 16 ), and wherein the spring-loaded restrictor plate ( 50 ) is annular and substantially coaxially aligned with the central longitudinal axis ( 16 ).

12. The MR damper system ( 60 ) of claim 11 , wherein the spring-loaded restrictor plate ( 50 ) moves substantially parallel to the central longitudinal axis ( 16 ) when the electromagnetic valve ( 26 ) transitions between the first and second states.

13. The MR damper system ( 60 ) of claim 12 , wherein the restrictive channel ( 52 ) bends an MR fluid flow ( 54 ) therein substantially ninety degrees.

14. A magnetorheological piston assembly ( 10 ) comprising;

a piston ( 12 ) extending a longitudinal axis ( 16 ) between first and second longitudinal ends ( 18 and 20 ) and defining an passageway ( 22 ) extending between said first and second longitudinal ends ( 18 and 20 ) for conveying an MR fluid therebetween,

a main electric coil ( 24 ) for magnetically energizing the MR fluid in said passageway ( 22 ),

an electromagnetic valve ( 26 ) operatively connected to said passageway ( 22 ) including a resistor plate ( 50 ) moveable between a first state for allowing the MR fluid to unobstructedly flow through said passageway ( 22 ) and a second state for restricting the flow of the MR fluid through said passageway ( 22 ), and

said electromagnetic valve ( 26 ) further including an electromagnetic valve coil ( 32 ) for imparting a magnetic force on said resistor plate ( 50 ) to move said resistor plate ( 50 ) between said first and second states.

15. The assembly ( 10 ) as set forth in claim 14 further including a spring ( 56 ) engaging said resistor plate ( 50 ) for biasing said resistor plate ( 50 ) to one of said first and second states.

16. The assembly ( 10 ) as set forth in claim 14 wherein said resistor plate ( 50 ) defines a restrictive channel ( 52 ) which is disposed out of fluid communication with said passageway ( 22 ) in said first state and which is disposed in fluid communication with said passageway ( 22 ) in said second state.

17. The assembly ( 10 ) as set forth in claim 14 further including a rod ( 14 ) attached to said piston.

18. The assembly ( 10 ) as set forth in claim 17 further including a controller ( 62 ) and a first wire ( 28 ) extending from said controller ( 62 ) through said rod ( 14 ) to said main electric coil ( 24 ).

19. The assembly ( 10 ) as set forth in claim 18 further including a second wire ( 30 ) extending from said controller ( 62 ) through said rod ( 14 ) to said electromagnetic-valve coil ( 32 ).

20. The assembly ( 10 ) as set forth in claim 14 wherein said piston ( 12 ) defines a piston core ( 40 ) and includes a piston ring ( 42 ) radially spaced from said piston core ( 40 ) to define said passageway ( 22 ) between said piston core ( 40 ) and said piston ring ( 42 ).