With the increase in high-rise buildings, elevators with high transporting ability and shorter waiting times have been in high demand. Up until now, elevator makers had responded by making elevators faster and producing double-decker elevators, but there was a limit to how fast elevators could go, and with double-deckers, the people in one car had to wait when the other car stopped.
Revolving elevators had been seen as a key to the problem, but lack of the technology to move them proved an obstacle. Designers considered a linear motor system using electromagnets, but the huge amount of electricity they used and safety concerns in the event of power failure remained problems.
The revolving elevator Hitachi produced was developed for a 20-story building, using eight elevator cars. The system uses cables, like conventional elevators, but rather than fixing the tops and bottoms of the cables, four pairs of cables are arranged in rings to carry the eight cars. The carriages are placed at opposite angles, and the elevators move in pairs, with one car going down while the other goes up.
Since the elevators operate in pairs, when one of the elevators in the pair stops, the other one does too, but the system is still more efficient than double-decker types.
Is that crazy or what?