Patent ID: 6318521
Filing Date: 2001-11-20
Classification: F16F

Abstract:
A vibration damping device including:a housing having first and second ends and forming an internal piston chamber;a piston axially movable within the housing and piston chamber and dividing said chamber into two separate fluid subchambers;a fluid transfer duct formed between said housing and piston providing fluid communication between said fluid subchambers on opposite sides of said piston, said fluid subchambers adapted to be filled with an electrorheological (ER) fluid;an electrode attached to one of the housing and piston for applying an electric field across at least a portion of the fluid transfer duct to increase the flow resistance of the ER fluid passing therethrough;a piston rod having first and second ends connected to the piston and extending beyond opposite ends of said piston with the first end of said piston rod being adapted to be connected to a first support structure;connection means mounted on the second end of the housing for connecting said second end of the housing to a second structure spaced from the first structure, whereby load on said damping device is supported by said housing and piston rod;first and second piston-rod-guide-assemblies mounted adjacent respective ends of the housing and slidably supporting the first and second ends, respectively of the piston rod therein, each of the rod guide assemblies being mounted in an end closure ring mounted in respective ends of the housing with one of said closure rings being slidably mounted within the piston chamber and the other of said closure rings being fixed at an opposite end of said piston chamber, each of said first and second guide assemblies having a slide bushing formed with a bore for slidably receiving and supporting a respective one of the first and second ends of the piston rod therein and an elastomeric seal surrounding the piston rod and located between each of said slide bushings and the piston chamber to seal said slide bushings from contact with the ER fluid.