DISK DRIVE DEVICE

PURPOSE:To reduce the size and the weight of a disk drive device with no deterioration of the reliability by identifying a magnetic disk cartridge FD and deciding the loading or the non-loading of the disk cartridge FD with use of a deciding means via plural identifying means. CONSTITUTION:A sensor controller is provided with a sensor part 161 to detect the states of the write protectors 81, 381 and 481 set at the common position to the floppy disks 1, 301 and 401 respectively. Then the sensor parts 162 and 163 are provided at the positions corresponding to an identification port 491 of a floppy disk 401 of 2MB and an identification port 91 of the disk 1 of 4MB respectively. These parts 161 - 163 send out the H signals when the identification ports are detected and then the L signals when no identification port is detected. Thus plural deciding means combines the levels of the signals to identify the FDs and to decide whether the FDs are loaded or not. As a result, the number of FDs to be identified by a single sensor part are decreased. Then a head is separated from the disk when a drop-out state is detected. Thus the scratches are minimized on the disk surface and furthermore a compact and light-weight disk drive device is obtained.