초록 ▼

A magneto-rheological (MR) damper provides a higher than minimum level of damping when a power source to the MR damper is not supplying a control current. The present invention damper includes magnets positioned to direct a magnetic flux across a MR fluid path. The fluid path is created when a rod a

A magneto-rheological (MR) damper provides a higher than minimum level of damping when a power source to the MR damper is not supplying a control current. The present invention damper includes magnets positioned to direct a magnetic flux across a MR fluid path. The fluid path is created when a rod and piston assembly stroke the fluid though a control valve assembly attached to a damper chamber causing a resistance to MR fluid flow. An electric coil cancels an effect of the permanent magnets when the control current is available to allow a control circuit more operating range. The permanent magnets allow for damping when no control current is available.

대표청구항 ▼

1. A magnetorheological (MR) damper assembly comprisinga housing with a first end and a second end; a piston attached to a rod, said rod and said piston being contained within said housing and movable within said housing; a first chamber and a second chamber, each said chamber filled with a MR fluid

1. A magnetorheological (MR) damper assembly comprisinga housing with a first end and a second end; a piston attached to a rod, said rod and said piston being contained within said housing and movable within said housing; a first chamber and a second chamber, each said chamber filled with a MR fluid, said first chamber formed between said piston and said first end of said housing; said second chamber formed between said piston and said second end of said housing; a control valve assembly adjacent said housing for controlling flow of said MR fluid between said first chamber and said second chamber, comprising: a first orifice and a second orifice fluidly connecting said first chamber with said second chamber respectively, a magnetic core with a plurality of coils for controlling a fluid flow through said control valve assembly when a power supply to said control valve assembly is in an on condition supplying a current to said plurality of coils; a power off control assembly mounted on said magnetic core, said power off control assembly comprising a second coil and a plurality of magnets, said second coil being activated by said magnets when said power supply is in an off condition, said power off control assembly being operable to control said fluid flow through said control valve assembly when said power supply is in an off condition; means for operably connecting said first opening of the control valve to said first chamber to provide fluid communication therewith; means for operably connecting said second opening of the control valve to said second chamber to provide fluid communication therewith.