Double-tube shock absorber using a hydraulic fluid and a magnetorheological fluid

摘要

A double-tube shock absorber includes an outer cylinder (112) having a first working chamber (116), an inner cylinder (114) located inside the first working chamber and having a second working chamber (118), a first piston (132) movably inserted into the first working chamber and a second piston (142) having a coil and movably inserted into the second working chamber. The first and the second working chamber are filled with a hydraulic fluid (126) and a magnetorheological (MR) fluid (128), respectively. The first and the second piston have one or more orifices, respectively. The double-tube shock absorber further includes one or more first piston rods (152) for leading the first piston in a reciprocating motion and a second piston rod (154) for leading the second piston in a reciprocating motion. The double-tube shock absorber can sensitively respond to the impulse applied thereto by using the hydraulic fluid having relatively low viscosity and, at the same time, can modulate the damping force by using the MR fluid having changeable viscosity.