An automatic tightening closure device for doors and hatches comprising: a first lock adapted to be mounted onto a door associated with a corresponding opening, said first lock comprising a rod; a second lock adapted to be mounted onto the edge of said opening in a corresponding position, facing said first lock, said second lock comprising a mouth movable between a first position, corresponding to the opening of the door, in which said mouth does not interfere with the end of the rod, and a second position, in which said mouth can engage the end of the rod and force the closing of the door; moving means connected to said movable mouth and further associated with means for detecting the position of said rod with respect to said mouth, wherein said movement means connected to said movable mouth are adapted to hold said movable mouth in a closed position when the alignment between said rod and said mouth is sufficient to allow the mutual engagement thereof, wherein said moving means connected to said movable mouth comprise a shaft connected to said movable mouth associated with an electric motor provided with a drive circuit, characterized in that the electric motor is provided with a first cam integrally connected to the end of the shaft of said electric motor and adapted to engage a second cam integrally connected to an end of said shaft and associated with resistant means adapted to hold said second cam in the position corresponding to the open position of the movable mouth, said first cam and said second cam being capable of rotating between two end positions, one corresponding to the opening of the movable mouth, the other corresponding to the closure of said movable mouth. a first lock adapted to be mounted onto a door associated with a corresponding opening, said first lock comprising a rod; a second lock adapted to be mounted onto the edge of said opening in a corresponding position, facing said first lock, said second lock comprising a mouth movable between a first position, corresponding to the opening of the door, in which said mouth does not interfere with the end of the rod, and a second position, in which said mouth can engage the end of the rod and force the closing of the door; moving means connected to said movable mouth and further associated with means for detecting the position of said rod with respect to said mouth, wherein said movement means connected to said movable mouth are adapted to hold said movable mouth in a closed position when the alignment between said rod and said mouth is sufficient to allow the mutual engagement thereof, wherein said moving means connected to said movable mouth comprise a shaft connected to said movable mouth associated with an electric motor provided with a drive circuit, characterized in that the electric motor is provided with a first cam integrally connected to the end of the shaft of said electric motor and adapted to engage a second cam integrally connected to an end of said shaft and associated with resistant means adapted to hold said second cam in the position corresponding to the open position of the movable mouth, said first cam and said second cam being capable of rotating between two end positions, one corresponding to the opening of the movable mouth, the other corresponding to the closure of said movable mouth.