Abstract: A rail installation assist device includes at least control circuitry. The control circuitry is configured to acquire displacement information representing displacement of individual rail brackets and a rail joint from a reference position, the rail brackets that fix guide rails in an elevator shaft, the rail joint that joins the guide rails together; estimate, from the displacement information, a change in the displacement information of the rail brackets and the rail joint when the rail brackets are moved to given target positions; calculate an evaluation value for variation in the displacement information before the change and an evaluation value for variation in the displacement information after the change; and set positions of the rail brackets based on a result of comparison between the evaluation values.

Abstract: A rail installation assist device includes at least control circuitry. The control circuitry is configured to acquire displacement information representing displacement of individual rail brackets and a rail joint from a reference position, the rail brackets that fix guide rails in an elevator shaft, the rail joint that joins the guide rails together; estimate, from the displacement information, a change in the displacement information of the rail brackets and the rail joint when the rail brackets are moved to given target positions; calculate an evaluation value for variation in the displacement information before the change and an evaluation value for variation in the displacement information after the change; and set positions of the rail brackets based on a result of comparison between the evaluation values.

Abstract: An elevator door system including a landing door, a car door provided on a car, a latch device for locking the landing door when the landing door is closed. The elevator door system also includes a door locking device provided on the landing door composed of a coupling plate for coupling with the car door, an unlocking plate provided in parallel with the coupling plate, and a link for moving the unlocking plate toward the coupling plate. The elevator door system further includes a first linking mechanism for linking the door locking device with the latch device, and a coupling device provided on the car door composed of a pair of coupling rollers for coupling the car door with the landing door. One of the coupling rollers pushes the unlocking plate toward the coupling plate when the car lands the landing floor. A displacement of the unlocking plate caused by being pushed toward the coupling plate by the link is applied to the latch device.