Mount for subframe and magnetorheological elastomer unit
When forces are input to a mount in a plurality of directions, an ECU changes the magnitude of a coil excitation current to change the strength of a magnetic field. At this moment, the elastic force of the mount can be changed in directions in response to the plurality of directions in which the forces are input using a plurality of magnetorheological elastomers (a brim-shaped MRE portion and a cylindrical MRE portion) in which magnetic particles are arranged in different manners.
1. A mount for a subframe disposed on the subframe at a position where the subframe is supported by a vehicle body, the mount comprising:
an inner cylinder composed of a magnetic body having a hollow shaft portion for fastening the mount to the vehicle body;
an outer cylinder composed of a magnetic body coaxially disposed on a radially outer side of the inner cylinder;
a magnetorheological elastomer disposed between the inner cylinder and the outer cylinder; and
a coil configured to apply a magnetic field to the magnetorheological elastomer to change viscoelasticity of the magnetorheological elastomer;
wherein the magnetorheological elastomer comprises a plurality of the magnetorheological elastomers including magnetic particles arranged in different manners,
the plurality of the magnetorheological elastomers include at least a first magnetorheological elastomer and a second magnetorheological elastomer;
the magnetic particles in the first magnetorheological elastomer are arranged parallel to a direction of an axis of the inner cylinder; and
the magnetic particles in the second magnetorheological elastomer are radially arranged from a central axis of the inner cylinder in directions perpendicular to the axis.
2. The mount for the subframe according to claim 1 , further comprising:
an elastic body having a cylindrical shape disposed between the inner cylinder and the outer cylinder.
3. A magnetorheological elastomer unit comprising:
a first cylindrical portion composed of a magnetorheological elastomer in which magnetic particles are arranged in a direction of an axis of the first cylindrical portion; and
a second cylindrical portion having a diameter different from the diameter of the first cylindrical portion and composed of a magnetorheological elastomer in which magnetic particles are radially arranged in directions perpendicular to an axis of the second cylindrical portion;
wherein the first cylindrical portion and the second cylindrical portion are disposed on top of each other on a common hollow shaft.
4. The magnetorheological elastomer unit according to claim 3 , wherein:
the second cylindrical portion has a diameter smaller than the diameter of the first cylindrical portion; and
the first cylindrical portion and the second cylindrical portion disposed on top of each other on the common hollow shaft form a flange shape.