Patent ID: 8235882

Claim:
A centrifuge comprising a drum with an axis of rotation and a housing for the drum, said housing comprising a lower part and a lid, the lid being attached to the lower part by at least one hinge comprising two hinge parts one of which is connected to the lid and one of which is connected to the lower part, said hinge having a horizontal hinge axis, whereby the lid is able to rotate around the hinge axis between a closed position, in which a centre of gravity of the lid is positioned on a proximal side of a vertical plane through the hinge axis, and a fully opened position, in which the centre of gravity is positioned on a distal side of the vertical plane through the hinge axis, the lid being provided with a handle for manually opening the lid, at least one spring unit being attached to the hinge for assisting raising of the lid during opening, the spring unit being a longitudinal spring unit having a longitudinal direction, the spring unit being connected to a connection member for urging the connection member in the longitudinal direction, the connection member being connected to one of the hinge parts at a hinge point at a distance from the hinge axis, the spring unit having a neutral extension in which it is not urging the connection member in the longitudinal direction, when the lid is in an intermediate position between its closed position and its fully opened position, the spring unit being stressed away from its neutral extension to urge the connection member in the longitudinal direction and thus the lid in a direction towards the fully opened position, when the lid is in the closed position, wherein the connection member is connected to the spring unit to stress it during at least a final part of the lids rotation around the hinge axis to the fully opened position, whereby the spring unit will urge the lid through the connection member in a direction from the fully opened position towards the closed position, when the lid is in the fully opened position, and wherein the lid has a position of stable equilibrium in an intermediate position of the lid between the closed position and a vertical position, in which the centre of gravity is positioned vertically above the hinge axis.