Landing door loock

An improved device for locking the floor door of lifts, applied to a pair of doors or panels (10-12) of a floor door, sliding along an upper track (14) through respective slides (18-20) and along a lower threshold (16), comprises a primary keyhole (24), fixed to the crosspiece (22) of said floor door, whereto a pivoting lock (26) is connected, provided with a bolt (28) engaged with the primary keyhole (24) and the secondary keyhole (30); said device comprises a second bolt (32), placed at or in the proximity of, the lower end of the floor door and fixed inside one of said doors (10) or (12). The second bolt is articulated on a support (34) and pivots along a plane parallel to the plane that identifies the inside and/or outside surface of the same doors hooking the opposite door (10) or (12) to the fitting bolt (32) in a slit made into the door.