CENTRIFUGAL SEPARATOR

PROBLEM TO BE SOLVED: To have all the states exclusive of a perfectly locked state of a door judged as abnormal states and to sufficiently assure the safety of a user even in the event of the single fault state by detecting the moving quantity of a bar by a sensor for detecting the locking state of the door and judging the locking state of the door with the signal from the sensor by the microcomputer. SOLUTION: The door locking device of the centrifugal separator for separating the sample in a rotor is constituted by inserting a plunger 3 into a solenoid 2 fixed to a frame 1. This plunger 3 is vertically driven by the solenoid 2. A bar 5 used for locking the door 4 is fixed by a pin 6 to the plunger 3. The photosensor 7 is mounted at a position where light is shielded at the time of the locking state of the door. The photosensor is designed to prevent the fall of light to a light receiving part 18 when the light from a light projecting part 17 is shielded. Then, when the pin 6 desends the photosensor 7 is put into a light incident state by the fall of the light from the light projecting part 17 to the light receiving part 18. The signal is then turned off and the abnormal state is judged by the microcomputer 10.