To improve external appearance by making it such that a lock structure of the unit not be seen from outside and to enhance the useability by precluding the possibility of mis-operation of the lock of the unit or reducing mis-operations and allowing the user to confirm the locking.
A battery unit 12 is set in a structure, consisting of a device main body 1 and a cover 3 in pairs which are folded in mutual directions and inserted in the inside via an opening 11 of the device main body 1. The device main body 1 is provided with a unit lock member 15 that is moved in a lock release direction, in response to the insertion of the battery unit 12 and a spring 23 energizing the member 15 in the lock direction, and the cover 3 turnably supports one end of an opening/closing guide 9, the other end of the opening/ closing guide 9 is engaged with the unit lock member 15, in response to the opening of the cover 3 to move the unit lock member 15 in the lock release direction via the opening/closing guide 9.
ISOE TOSHIO
HANEDA ISAMU
