| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the axial load acting on hemi-spherical bearings and a hemi-spherical bush by providing a separation device for maintaining permanents magnets in a non-contact state between the hemi-spherical bearings and hemi- spherical bush. SOLUTION: Permanent magnets are provided respectively to a plane section opposing upper and lower side hemi-spherical bearings 124a and 124b to each other, and one more permanent magnet connected to a hemi-spherical bush 122 is provided between the two permanent magnets. In that case, three permanent magnets are so arranged up and down in one row that repulsive force can be developed. Since a rotational polyhedral mirror device constituted by such constitution maintains a state to separate the hemi-spherical bearings 124a and 124b and hemi-spherical gutters 126a and 126b from each other by repulsive force of the permanent magnets in an original state to have a power source not being applied, and when the power source is applied to rotate a rotary body, rotation is made more smoothly.</p> |
