I don't know what a gantry lift is really supposed to describe but if it's not a hotel elevator, the doors thing bothers me less.
A gantry is a (usually) scaffold-like structure to create a high beam from which you can hang things, especially a pulley from which you can create a lift/elevator system for materials or people. Often the pulley can slide along the top beam so that the things/people being hoisted can move laterally as well as up and down. Modern elevators and cranes have supplanted the widespread use of gantries. Consequently, a work-elevator meant more for supplies than people will sometimes still be called a gantry lift/elevator.