Elevator Traffic Control Including Destination Grouping

• US 20080245618A1
• Filed: 12/20/2005
• Published: 10/09/2008
• Est. Priority Date: 03/18/2005
• Status: Active Grant

• Current Assignee: Otis Elevator Company (Otis Worldwide Corp.)
• Original Assignee: Otis Elevator Company (Otis Worldwide Corp.)
• Inventors: Williams, Daniel S., Stanley, Jannah A., Honma, Hideyuki, Simcik, Paul, Mori, Toshimitsu
• Granted Patent: US 7,921,968 B2
• Time in Patent Office: Days
• US Class Current: 187/383
• CPC Class Codes: B66B 1/20 and for varying the manner of operation to suit particular traffic conditions, e.g. "one-way rush-hour traffic" B66B1/2466 takes precedence
• CPC Class Codes: B66B 3/00 Applications of devices for indicating or signalling operating conditions of elevators
• CPC Class Codes: B66B 3/006 for guiding passengers to their assigned elevator car

Abstract

A elevator traffic control technique includes destination grouping that is selectively implemented during selective traffic conditions by a system controller (36). If, for example, an up-peak traffic condition exists, passenger-to-car (30,20) assignments are grouped bused on passengers'"'"' desired destinations.

Claims

1. A method of controlling elevator traffic, comprising:

determining a plurality of desired passenger destinations before the passengers enter an elevator car; and

grouping passenger-to-car assignments according to the determined destinations if a selected elevator traffic condition exists.

2. The method of claim 1, wherein the selected traffic condition comprises an up peak traffic condition.

3. The method of claim 2, comprising determining that the up peak traffic condition exists by determining a number of desired passenger destinations above a selected originating floor within a selected period of time.

4. The method of claim 2, comprising determining that the up peak traffic condition exists by determining a time of day.

5. The method of claim 1, comprising grouping the passenger-to-car assignments such that an elevator car travels to only one desired passenger destination after departing from an originating floor.

6. The method of claim 1, comprising grouping the passenger-to-car assignments such that an elevator car travels to only contiguous desired passenger destinations after departing from an originating floor.

7. The method of claim 1, comprising grouping the passenger-to-car assignments within a plurality of sectors such that at least one elevator car travels to each sector and each floor from the determined plurality of desired passenger destinations is included in only one sector.

8. The method of claim 1, comprising determining at least one characteristic of elevator traffic during a recent time interval having a selected duration;

and

determining a size and a number of sectors for grouping the passenger-to-car assignments based on the at least one determined characteristic.

9. The method of claim 8, including determining the elevator system capacity and using the determined capacity for determining the size and number of sectors.

10. The method of claim 1, comprising:

determining a first number of requests corresponding to desired passenger destinations in an up direction from an originating floor, a second number of requests corresponding to desired passenger destinations in a down direction toward the originating floor and a third number of requests corresponding to desired passenger destinations corresponding to travel between floors above the originating floor, respectively, within a selected time interval; and

determining if the selected elevator traffic condition exists based on the determined number of requests and the elevator system capacity for the selected time interval.

11. The method of claim 1, comprising

determining a maximum number of sectors based upon a configuration of a corresponding elevator system;

determining a number of requests corresponding to the plurality of determined desired passenger destinations during a selected time interval corresponding to up peak traffic;

determining a handling capacity of the corresponding elevator system during the selected time interval;

determining a number of elevators from the corresponding elevator system available to serve the passengers;

determining a percentage of up peak traffic requests from the determined number of requests from the selected time interval; and

determining a current number of sectors to be used if the selected elevator traffic conditions exists by multiplying the determined percentage of up peak traffic times the determined maximum number of sectors multiplied by the determined number of requests corresponding to up peak traffic divided by the determined handling capacity.

12. The method of claim 11, comprising determining whether the determined current number of sectors exceeds a threshold wherein the selected elevator traffic condition exists when the determined current number of sectors exceeds the threshold.

13. The method of claim 12, comprising

determining how many floors to group into each of the current sectors by dividing the number of floors above an origination floor by the determined current number of sectors.

14. The method of claim 13, comprising

evenly dividing the floors above the origination floor into sectors if the number of floors above the origination floor are evenly divisible into the determined current number of sectors.

15. The method of claim 11, comprising

restricting the maximum number of sectors to a number less than the determined number of elevator cars.

16. The method of claim 1, comprising

selecting a sector from a current set of sectors that includes a determined desired passenger destination;

determining whether an elevator car is currently assigned to the selected sector;

determining whether a first car assigned to the selected sector has capacity to service a request for the desired passenger destination; and

designating the first car in the selected sector as a best sector car if the first car has the capacity.

17. The method of claim 16, comprising

determining which one of a plurality of available elevator cars will reach the origination floor first;

designating the determined car as the best sector car if the first car does not have the capacity to service the request for the desired passenger destination.

18. The method of claim 17, comprising

determining an amount of time it will take for the designated best sector car to reach the origination floor;

determining whether the determined amount of time exceeds an acceptable wait time threshold; and

assigning the request for the desired passenger destination to the designated best sector car if the determined amount of time is less than the acceptable wait time threshold.

19. The method of claim 18, comprising

designating a different car as a best car for serving the request for the desired passenger destination if the determined amount of time exceeds the acceptable wait time threshold;

and

determining whether a difference in arrival time at the origination floor of the designated best sector car and the designated best car exceeds a selected threshold if the arrival time of the designated best car is earlier than the arrival time of the designated best sector car; and

assigning the request for the desired passenger destination to the designated best car if the determined difference exceeds the selected threshold.

20. The method of claim 1, comprising

determining an average time between requests for at least some of the determined plurality of desired passenger destinations that are all within a single sector;

determined an expected number of passengers to board an elevator car at an origination floor; and

extending a wait time for the elevator car at the origination floor if the determined average time indicates that another desired passenger destination request will be received for that sector within a selected time interval and the elevator car has capacity to receive at least one more passenger.