Lift cages with improved blocking/releasing devices

A lift cage door comprising:

• a crosspiece,
• an access aperture and two cage doors
• the cage doors being operatively connected to a first motor element which moves the cage doors from an open position to a closed position, and wherein said cage doors are mechanically connected to one or more chutes,
• wherein the cage comprises a second motor element mechanically and operatively separate from the first motor element, wherein said second motor element is connected to a blocking/releasing carriage of the cage doors,
• wherein said blocking/releasing carriage is connected to at least one hooking device connected to at least one of said cage doors, so as to permit the blocking/releasing of the one or more chutes independently of the actuation of the first motor element and of the cage doors,
• wherein the blocking/releasing carriage is provided with seats suitable for housing and engaging with actuation elements of the chute,
• wherein said seats are delimited by profiles which receive the actuation elements of the chute so that when the cage doors are in the open position the actuation elements are disengaged and are not in contact with the profiles,
• and when the cage doors are in the closed position said profiles comprise an entrance slot to facilitate the insertion of the actuation elements inside said seats, and
• wherein the blocking/releasing carriage is provided with an irreversible kinetic coupling to prevent the chutes from disengaging without the prior activation of the second motor element.