Abstract: A magnetorheological (MR) piston ring includes an MR-piston-ring body disposable within a cylinder of an MR damper along a central longitudinal axis. The MR-piston-ring body has a radially inner surface defining a boundary of a longitudinally-extending MR passageway. The MR-piston-ring body includes a surface portion which is slidingly engagable with the cylinder and which has first and second longitudinal ends. The surface portion includes at least one surface groove each defining a secondary MR passageway and extending between the first and the second longitudinal ends. The surface groove is substantially straight and tilted with respect to a line drawn on the surface portion parallel to the central longitudinal axis. An MR damper including the MR piston ring is also described.

Abstract: A magnetorheological (MR) piston ring includes an MR-piston-ring body disposable within a cylinder of an MR damper along a central longitudinal axis. The MR-piston-ring body has a radially inner surface defining a boundary of a longitudinally-extending MR passageway. The MR-piston-ring body includes a surface portion which is slidingly engagable with the cylinder and which has first and second longitudinal ends. The surface portion includes at least one surface groove each defining a secondary MR passageway and extending between the first and the second longitudinal ends. The surface groove is substantially straight and tilted with respect to a line drawn on the surface portion parallel to the central longitudinal axis. An MR damper including the MR piston ring is also described.

Abstract: A magnetorheological (MR) piston ring includes an MR-piston-ring body disposable within a cylinder of an MR damper. The MR-piston-ring body has a radially inner surface defining a boundary of a longitudinally-extending MR passageway. The MR-piston-ring body includes a surface portion which is slidingly engagable with the cylinder and which has first and second longitudinal ends. The surface portion includes at least one surface groove each defining a secondary MR passageway and extending from the first to the second longitudinal end or each defining an MR cavity extending from one of the first and second longitudinal ends toward, but not to, the other of the first and second longitudinal ends. An MR damper including the MR piston ring is also described.

Abstract: A magnetorheological (MR) piston ring includes an MR-piston-ring body disposable within a cylinder of an MR damper. The MR-piston-ring body has a radially inner surface defining a boundary of a longitudinally-extending MR passageway. The MR-piston-ring body includes a surface portion which is slidingly engagable with the cylinder and which has first and second longitudinal ends. The surface portion includes at least one surface groove each defining a secondary MR passageway and extending from the first to the second longitudinal end or each defining an MR cavity extending from one of the first and second longitudinal ends toward, but not to, the other of the first and second longitudinal ends. An MR damper including the MR piston ring is also described.

Abstract: A damper provides tunable variable rates in both extension and compression operation. A piston is carried in a cylinder tube separating out extension and compression chambers. The piston carries a first valving assembly that is tuned to provide a first damping level when fluid flows through the piston from the extension chamber to the compression chamber and a second valving assembly that is tuned to provide a second damping level when fluid flows through the piston from the compression chamber to the extension chamber. A control valve assembly is mounted to move with the piston. When the control valve assembly is closed, fluid flow between the compression and extension chamber flows substantially only through the first and second valving assemblies and when the control valve is open at least some fluid flows between the compression and extension chambers through a secondary valve assembly without passing through the first and second valving assemblies.