| 摘要 |
The present invention relates to a step motor with a preload member used for optical pickup devices such as OA devices and optical disk drive devices. More specifically, the step motor includes: a motor unit which is composed of a stator, a rotor with a rotation shaft, and a case; a lead screw which is combined with one end of the rotation shaft to be rotatable; a center guide which includes a supporting member at one end of the case and supports the other end of the rotation shaft on the internal diameter of the supporting member; and the preload member which preloads the center guide towards the rotation shaft. The preload member includes an elastic piece bent at a certain angle at the center thereof and preloads the center guide towards the rotation shaft. The preload member includes a stopper unit in a part where the elastic piece is not formed, so when the center guide is pushed in the opposite direction of preloading, the center guide is stopped by the stopper unit at a certain position to prevent the center guide from being pushed away. By doing so, even if the center guide is pushed completely in the opposite direction of the preloading by the preload member, the elastic piece of the preload member maintains the preloading force, so the reduction of the spring load (spring constant) can be prevented. |
