Disc centering device

A disc centering device includes a base plate, a chuck which is installed on the base plate, a hub unit which is detachably engaged to the chuck and receives discs and spacers to be stacked, disc pushers which are slidably provided outside the hub unit and include corresponding pressure members which center the discs by pushing circumferences of the discs, a driving unit which slides the disc pushers, and biasing units which are slidably provided outside the hub unit and push circumferences of the spacers. Accordingly, by performing a spacer biasing along with a disc centering, the accuracy of a centering is increased, thereby providing the discs having data recorded thereon with a uniform quality. Additionally, vibration of a rotation body can be minimized due to the simple configuration of the disc centering device. Furthermore, the productivity and manufacturability of HDDs are improved in view of the simplified maintenance and repair of the same.