A MO cartridge jukebox cartridge door and closure mechanism which employs a pair of parallel door panels and a pair of parallel cranks all connected together to form a parallelogram which is moved by engagement with a mechanical linkage to the cartridge receiving tray within the jukebox to ...http://www.google.com/patents/US5689490?utm_source=gb-gplus-sharePatent US5689490 - MO cartridge jukebox doors which open in a plane parallel to the front panel of the jukebox 
