Spring operated device for door movement, having an adjustable lever arm of the spring

摘要

A movement device for pieces of furniture, for articulating a door with respect to a stationary structure, comprises a first articulation element (12; 12a . . . ) linked to the door and pivotable with respect to the stationary structure, and a second articulation element (14) hinged to the stationary structure, the ends of said two articulation elements being hinged together, the first articulation element having an elastically variable extension, so that said two elements may assume with respect to one another a stable retracted position and a stable extended position, passing through a succession of unstable positions, and further comprises adjusting means (30; 30a; 30b . . . ) for adjusting the distance between an axis (a16) of the hinge between the two elements and a rotation axis (a13) of the second element with respect to the stationary structure.