Piston rod surface finish requirement for MR dampening devices
AssigneeDelphi Technologies, Inc.
InventorsIlya Lisenker, Patrick Neil Hopkins, William Charles Kruckemeyer
Life of this patent
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Abstract
A piston rod for use in a magnetorheological dampening device having a surface finish that renders the device resistant to wear at the elastomeric seal/piston rod interface. The piston rod has a surface finish of Ra<0.065 μm and Δa≦1.4°, as measured using a Gaussian filter with a 0.08 mm cut-off length. There is further provided a method of achieving the surface finish, including rotating the piston rod while moving an abrasive tape against the outer surface of the rod.
Claims15
A method for finishing the surface of a piston rod for use a magnetorheological dampening device, the method comprising:
- rotating the piston rod;
- and
- pressing against an outer surface of the rotating rod an abrasive tape for a time sufficient to achieve a surface finish of Ra<0.065 μm and Δa≦1.4°, as measured using a Gaussian filter with a 0.08 mm cut-off length.
A method for finishing the surface of a piston rod for use a magnetorheological dampening device, the method comprising:
- placing the piston rod between two driven rollers to rotate the piston rod in a first direction;
- and
- moving against an outer surface of the rotating rod an abrasive tape in the first direction for a time sufficient to achieve a surface finish of Ra<0.065 μm and Δa≦1.4°, as measured using a Gaussian filter with a 0.08 mm cut-off length.
A piston rod for use in a magnetorheological dampening device containing an MR fluid having particles of less than about 16 μm in diameter, the rod having a surface finish of Ra<0.065 μm and Δa≦1.4°, as measured using a Gaussian filter with a 0.08 mm cut-off length.
A magnetorheological dampening device comprising an elastomeric seal slidably receiving a piston rod having a surface finish of Ra<0.065 μm and Δa≦1.4°, as measured using a Gaussian filter with a 0.08 mm cut-off length, and an MR fluid having particles of less than about 16 μm in diameter in fluid communication with the rod and seal.
Dependencies are inferred from the claim text.