A lifting assembly comprising parallel guides (18, 20), a carriage (26, 28) associated with each parallel guide (18, 20) and movable along the length of the parallel guides, a displacement arm (40) pivotally connected to each carriage (26, 28) and pivotally supporting a bridge (14), preferably a trolley (13) located on the bridge (14) including attachment means (12) for supporting a lifting device.