Operating device in a dish-washing machine

A locking device for a dish-washing machine having a vertically movable hood adapted to take an open position and a closed position, respectively, said hood being locked in its closed position during a cleaning operation, comprising:

• a locking means, an actuating member provided on said hood and co-acting with said locking means, and electro-magnetic means operating to inactivate said locking means, wherein said locking means includes a curved part and a curve follower, an elastic member being provided for biasing said curved part into engagement with said curve follower, said curved part having a recess and a sloped portion, and a sharp edge interconnecting said recess and sloped portion, said actuating member during movement of the hood to its closed portion operating to bring said curve follower into said recess of the curved part, while said actuating member during movement of the hood to its open position operates to force said curve follower against the action of the said elastic means out of the recess through the sharp edge and to the sloped portion of the curved part.