Traditionally, traction elevators use ropes to transform rotational motion of an electric motor into vertical motion of the cabin. A new vertical passenger transportation system does not use any ropes – a linear motor directly provides the vertical driving force. The new propulsion for rope-free elevators is realized through a linear electric motor. The main advantages of the rope-free propulsion are the possibility to move multiple cabins in one shaft, and the possibility for elevator cars to move horizontally.
The primary goal of the project is the development of damping concepts in order to reduce vibrations inside the cabin of the rope-free passenger transportation system, thus achieving the highest level of passenger comfort.
The linear motor demands a lightweight design of the elevator car, due to the reduced load that the linear motor can carry compared to conventional propulsion system. Lightweight constructions render the system more susceptible to vibrations, due to the reduction in stiffness. The riding comfort of passengers decreases in the presence of vibrations and therefore this vibrations should be kept at an acceptable level. In conventional elevators, vibrations are reduced by passive damping elements that are placed in the mounting frame around the exterior of the cabin. This construction decouples the elevator cabin from the rest of the elevator car and leads to an improved riding quality for the passengers. The new structure of the rope-free transportation system omits the mounting frame around the cabin, due to the linear motor, but on the other hand, the high passenger comfort of conventional elevators shall be kept for the rope-free transportation system. It is therefore essential to develop a damping concept that fits the new requirements and achieves a high passenger comfort. One way to reduce the vibration is to accompany passive damping elements by active damping components.
The damping concept for the rope-free passenger transportation system is developed in cooperation with the thyssenkrupp Elevator Innovation GmbH. The damping concept will be implemented on the rope-free passenger transportation system of thyssenkrupp called MULTI. A mock-up of the MULTI will be implemented in the test tower of thyssenkrupp in Rottweil.
- J. Missler, T. Ehrl, B. Meier, S. Kaczmarcyk & O. Sawodny, “Modelling of a rope-free Passenger Transportation System for Active Cabin Vibration Damping”, 6th Symposium on Lift and Escalator Technologies, Northampton, United Kingdom, 2016