Group control for elevators

In a group control for elevators each having an elevator cabin and containing at least one storey call storage controllable by means of a storey call transmitter, cabin call storages for controlling by means of cabin call transmitters each cabin of the group, selectors operatively correlated with each elevator of the group indicating that storey at which the cabin still could stop, load measuring devices operatively correlated with each elevator cabin, a scanner device having at least one position for each storey, wherein each elevator is provided with a computer device possessing an adder which forms at least the distance between a considered storey and the selector position, the number of intermediate stops to be expected within such distance based upon the prevailing cabin and allocated storey calls as well as the momentary cabin load, a time-proportional sum corresponding to the servicing capability of a cabin of the group with respect to the considered storey, and at least one comparison device by means of which the cabin having the lowest servicing costs corresponding to the smallest previously computated loss time and therefore the optimum servicing capability can be allocated to the considered storey, the improvement which comprises:

• each elevator being provided with a computer device for counting the number of allocated storey calls and one of a number of cabin calls between a selector position and the considered storey;
• each elevator further being provided with a device which stores the momentary operating state of the elevator cabins;
• the computer device being provided with a subtractor unit for forming a difference from the number of said allocated storey calls multiplied by a number of passengers expected to enter the elevator cabin and the number of cabin calls multiplied by a number of passengers expected to exit from the elevator cabin;
• said difference and a momentary operating state of the elevator cabin being infeedable as a further summand to the adder of the computer device;
• the scanner device being connected with the computer device which for each position of the scanner device forms the sum corresponding to the servicing costs of a cabin with respect to a real or imaginary storey call of such position;
• a storage device connected with the computer device and the scanner device;
• said storage device can be filled by means of said scanner device;
• and
• said storage device receiving the correlations of the momentarily most optimumly employable cabin having the lowest servicing costs for the relevant position of the scanner device.