| 摘要 |
PURPOSE:To provide a deflector easy for working, capable of controlling the vibration of a rotation part in the direction of thrust due to external force and preventing the damage of a constitution member due to an external rapid shock and rotating in the optional direction by making a fixed shaft outer peripheral shape a specific shape and providing an air chamber whose pressure is changed according to the displacement the rotation part in the direction of thrust. CONSTITUTION:A fixed shaft 1 whose shaft outer peripheral shape is formed to a multi circular arc, e.g. three circular arc shape and is fixed to a case 11. Then, the air chamber 6 whose inner pressure is changed according to the displacement of the rotation part is arranged for adjusting the displacement in the direction of thrust of the rotation part of a dynamic pressure air bearing type light deflector forming a dynamic pressure generating radial bearing mechanism 9 between a hollow rotation shaft 2 and the fixed shaft 1, and a shock absorbent member 7a is arranged on an abutment part between the rotation part and the fixed part. In such a constitution, when vibration, shock, etc., are applied from the outside while the hollow rotation shaft 2 is rotated, the vibration of the rotation part in the direction of thrust is suppressed by the damper effect of the air chamber 6, and the rotation without the vibration in the direction of thrust is obtained. |
