A disk drive including a tray and an opener. The tray includes a disk cartridge mounted thereon and is loaded into and unloaded from a main body. The opener is installed in the main body and elastically contacts a guide formed on the tray. The opener includes a second gear and a first protrusion. The second gear rotates a rotating wheel when in contact with a first gear. The first protrusion formed on a first end of the second gear temporarily rotates the rotating wheel so that the first and second gears can mesh. The guide has a first cam that moves the opener such that the first protrusion does not interfere with the latch when the tray is loaded/unloaded.