US Patent 7533392 Disc apparatus

In the course of the loading of a disc in a slot-in type of disc apparatus, if a user intends to forcefully pull out the disc, there is a possibility that it is wrongly recognized that the disc has been normally loaded, and then a clamping head of a spindle motor collides against a surface of the disc to damage it. In order to solve this problem, during the loading operation of the disc, a safety mechanism for allowing a clamping operation in response to what the disc has reached a normally clamped position. The safety mechanism may be a mechanical stopper or an electrical detector.