Patent ID: 7213119

Claim:
A portable storage device comprising: a main unit including a receiving and ejecting device that receives a storage cartridge from an outside of said main unit into a predetermined inner position within said main unit, and ejects said storage cartridge out of said main unit from the predetermined inner position, and a storage operation control device that controls storage operation for storing data in said storage cartridges, wherein said storage cartridge includes a storage medium, a storage medium control device that performs writing of data in said storage medium and reading of data from said storage medium, and a casing that contains said storage medium and said storage medium control device; a receiving/ejecting operation determining device that determines which of a standby state in which a loading operation for receiving said storage cartridge is awaited, a loading state in which the loading operation is being performed, a loading completed state in which the loading operation has been completed, and an ejecting state in which an ejecting operation for ejecting said storage cartridge is being performed, the operative state of said receiving and ejecting device corresponds to; and an access inhibiting device that inhibits access to said storage medium based on control by said storage operation control device from being gained, when the operative state corresponds to one of the loading state and the ejecting state, wherein said access inhibiting device comprises a signal cutoff semiconductor device that electrically cuts off at least part of the electric signals transmitted between said storage operation control device and said storage cartridge.