Magnetorheological Devices with Permanent Field Bias

摘要

A magneto-rheological damping device comprises a piston (112) and a case element (116), both capable of acting to carry a magnetic flux. A passage (146) exists between the piston and the case element, and an amount of MR fluid (144) is positioned between the piston and the case element to flow within the passage. A first magnetic flux generator and a second magnetic flux generator cooperate to generate a net flux that is disposed to act upon the MR fluid in the passage to affect the flow of fluid in the passage. One of the flux generators comprises a permanent magnet (150) to generate a bias flux between the piston and the case element, and the other flux generator comprises a means (134) for providing a controllable magnetic flux between the piston and the case element.