Patent ID: 7647601

Claim:
A pickup drive mechanism comprising: a supporter for supporting a pickup device; a plurality of height-adjustable support shafts provided in parallel to each other and slidably supporting the supporter; and a lead screw for sliding the supporter along the height-adjustable support shafts, wherein the pickup device rotates around one of the plurality of height-adjustable support shafts when a posture of the supporter is changed by adjusting heights of the height-adjustable support shafts, the supporter has a screw abutting surface that is formed substantially in parallel to an axial direction of the lead screw while abutting on the lead screw, the screw abutting surface is angled to intersect respectively with a focus direction substantially orthogonal to a recording surface of a disc where a data is reproduced and/or recorded by the pickup device, and a plane direction orthogonal to the focus direction and substantially parallel to the height-adjustable support shafts, and the screw abutting surface being tangent to an arc, the arc including a contact point of the screw abutting surface and the lead screw, the arc being centered on a rotational axis coinciding with one of the plurality of height-adjustable support shafts, and a radius of the arc equaling a distance from the rotational axis to the lead screw; whereby the screw abutting surface abuts on the lead screw at a substantially constant angle as the pickup device rotates, such that a substantially constant driving force is transmitted from the lead screw to the supporter.