To provide a damping force adjusting device of small and light construction capable of reducing the power consumption, securing wide the variable range of the damping force by increasing and decreasing quickly and largely the viscosity of a magnetic fluid by effective convergence of the magnetic flux, and exerting a sufficient damper effect at all times for vibrations over a wide range.
A piston 1 made of a magnetic material is fitted slidably in a cylindrical casing 2 made of a magnetic substance, and ring-shaped recesses 1a, 1a in a plurality of stages are formed in the sliding direction at the periphery of the piston 1, and electromagnets 5A and 5B are accommodated in these recesses 1a, 1a in such a condition that their same polarities are confronting, and a capsule-form magnetic fluid 4 is interposed ring-shapedly between the inside surface of the casing 2 and the peripheral surface of the piston 1, and a magnetic flux control device is installed to adjust the size of the magnetic flux generated by a magnetic circuit 6 by changing the magnetic forces of the electromagnets 5A and 5B.
SAKATA TOSHIFUMI
OKU TAKESHI
OKAMOTO SHUICHI
