US 5,786,550 A · Dynamic scheduling elevator dispatcher for single source traffic conditions

Abstract

A elevator system including a group controller for controlling the dispatching of elevator cars to the lobby. The group controller predicts lobby single source traffic for short periods. When the predicted traffic is below certain limit, cars are assigned to a lobby hall call on demand after hall call registration. When the predicted traffic is above certain limit, cars are assigned to the lobby hall call at intervals. Accordingly, car assignment is scheduled at those intervals. The traffic threshold at which the scheduled mode is activated and the traffic threshold at which it is deactivated is learned by the system. The schedule interval is varied based on predicted traffic and predicted round trip time of the cars. The number of cars assigned and sent to the lobby is varied based on predicted traffic. In order to avoid oscillations in selecting the service mode, proper delays are used to activate and deactivate the scheduled service.

Claims18

Dependent claims

A system for controlling elevator cars in a building having a plurality of floors, said system comprising a group controller for controlling operation of the elevator cars during single source traffic conditions, said group controller assigning the elevator cars at a schedule interval to a lobby in response to a predicted traffic level reaching a determined threshold wherein if more than in one hall call out of a predetermined number of hall calls an elevator car is not available at the lobby for assignment to the hall call, the system sets a predicted traffic as a threshold for increasing the number of elevator cars assigned to the lobby.

A system, including a group controller, for controlling a plurality of elevator cars serving a plurality of floors in a building, said group controller repetitively, in each of a continuous series of time periods, determining the level of passenger traffic entering the elevators at a lobby floor, and in response to the level of traffic, alternatively, either

if the level of traffic is below a first threshold level, assigning a car to respond to a hall call at the lobby floor only in response to a hall call being registered at said lobby floor, or
if the level of traffic is above said first threshold level, without regard to whether a hall call is currently registered at the lobby floor or not, successively assigning cars to travel to the lobby floor and open their doors according to a schedule having a recurring interval of time between the time when one assigned car is scheduled to open its door at the lobby floor and the time when a next assigned car is scheduled to open its door at the lobby floor.

A method of controlling a plurality of elevator cars serving a plurality of floors in a building, comprising:

repetitively, in each of a continuous series of time periods, determining the level of passenger traffic entering the elevators at a lobby floor;
and
in response to the level of traffic, alternatively, either
if the level of traffic is below a first threshold level, assigning a car to respond to a hall call at the lobby floor only in response to a hall call being registered at said lobby floor, or
if the level of traffic is above said first threshold level, without regard to whether a hall call is currently registered at the lobby floor or not, successively assigning cars to travel to the lobby floor and open their doors according to a schedule having a recurring interval of time between the time when one assigned car is scheduled to open its door at the lobby floor and the time when a next assigned car is scheduled to open its door at the lobby floor.

2 more elements

Dependencies are inferred from the claim text.

Dynamic scheduling elevator dispatcher for single source traffic conditions

Life of this patent

Dynamic scheduling elevator dispatcher for single source traffic conditions

Life of this patent

Abstract

Claims18