The door has one or more levers (2) swung out by a first lever (13) on the vehicle and which slides in a guide in the leaf, and guided by a second lever (5) working in a guide (7) on the vehicle. The two levers are coupled to each other by a mechanism continuously regulating the distance between them, and which is actuated by a single drive mechanism (11). The second lever can be continuously driven during opening and shutting by a slide (6) travelling along a lengthwise main guide, while also actuating a thrust-rod mechanism (14,16) with rod working in an auxiliary guide (17). One end (16A) of this rod engages in the guide (18) on the leaf.
