Huge population density in megalopolises and the central parts of big cities led to the general increase in number of storeys of building and emergence of buildings by height in some hundred meters. Their construction became possible as a result of technological progress, however the high number of storeys generated a number of new problems. Therefore there were special express elevators.

Besides the increased speed of movement of a cabin, feature of a design and operation of multystoried buildings show to such elevators a number of additional requirements. High speed of movement of a cabin initially had a side effect in the form of unpleasant feelings at passengers at the time of the beginning and the end of movement. Modern high-speed elevators are relieved of this shortcoming at the expense of a gradual set of speed at the beginning of a trip and its gradual decrease beginning for some floors to the necessary floor. Modern express elevators are presented among other and models which work doesn't require existence of an engine room, and rather usual lift mine.

Even taking into account the high speed of movement of a cabin the capacity of high-speed elevators not always corresponds to real need, besides, that the increase in number of lift mines in already built multystoried buildings isn't possible for the reasons of technological character. Nevertheless, the capacity of available mines can be increased by means of the unexpected decision. In one mine two cabins, located the friend over the friend and operated by uniform automatic equipment can be placed. Thus each of cabins has own drive and a counterbalance. The suitable model of the high-speed elevator can be picked up today practically for any high-rise building, however proceeding from specifics of these mechanisms, them select at a building design stage.