To prevent the third person from touching a work or stealing it by providing a door lock means, with which a door is locked or unlocked based on the input of a password number from an input means provided at the main body of a machine, and unlocking the door after the lapse of prescribed time from the lock of the door.

When the power source of a main control part 2 is turned on, a controller 1 is made operable, a program starts and it is judged whether the password number is inputted to laundry 3a-3n or not. A person in charge to use the laundry 3a-3n opens the unlocked door of the laundry 3a-3n, puts objects to be washed into the laundry 3a-3n, closes the door and inputs the password number through an input/output part 12 of the laundry 3a-3n. At such a time, a lock signal is outputted from a control part 13 to a lock mechanism part 14 and the door of the laundry 3a-3n is locked. After the lapse of prescribed time, the door of the laundry 3a-3n is unlocked.