Method and apparatus to prevent or minimize the entrapment of passengers in elevators during a power failure

• US 20070084673A1
• Filed: 10/18/2005
• Published: 04/19/2007
• Est. Priority Date: 10/18/2005
• Status: Active Grant

• Current Assignee: ThyssenKrupp Elevator Corporation (Thyssenkrupp AG)
• Original Assignee: Thyssen Elevator Capital Corporation (Thyssenkrupp AG)
• Inventors: Peters, Richard, Smith, Rory, Al-Sharif, Lutfi
• Granted Patent: US 7,540,356 B2
• Time in Patent Office: Days
• US Class Current: 187/290
• CPC Class Codes: B66B 5/027 to permit passengers to leave an elevator car in case of failure, e.g. moving the car to a reference floor or unlocking the door

Abstract

The invention provides a system and method for handling power outages in a multiple car elevator system in a building having a plurality of floors. The system includes an energy calculator connected to the elevators, and determines a total energy of the elevator system, a total energy required to handle a power outage, a plan to prepare for a power outage and a plan to handle a power outage. The system also includes a movement controller connected to the elevator(s) and the energy calculator. The movement controller receives the plan to prepare and the plan to handle from the energy calculator, and the movement controller executes the plan to prepare if there is no power outage and the movement controller executes the plan to handle if there is a power outage.

Claims

1. An apparatus for handling power outages in an elevator system in a building having a plurality of floors, the apparatus comprising:

one or more elevators;

an energy calculator connected to the elevators and capable of determining a total energy of the elevator system, a total energy required to handle a power outage, a plan to prepare and a plan to handle; and

a movement controller connected to the elevator(s) and the energy calculator, wherein the movement controller receives the plan to prepare and the plan to handle from the energy calculator, and the movement controller executes the plan to prepare if there is no power outage and the movement controller executes the plan to handle if there is a power outage.

2. The apparatus of claim 1 wherein:

the elevator(s) comprise a variable speed drive and a direct current bus;

a common direct current bus is connected to the direct current bus of each elevator such that the variable speed drive of each elevator supplies power to the direct current bus when the elevator produces energy and consumes power from the direct current bus when the elevator consumes energy; and

,

the movement controller is connected to the variable speed drive of the elevator(s) and executes the plan to prepare and the plan to handle by controlling the variable speed drive of the elevator(s).

3. The apparatus of claim 2, wherein one or more capacitors are connected to the common direct current bus.

4. The apparatus of claim 2 or 3, wherein the elevators that are consuming power receive power from the common direct current to execute the plan to handle.

5. The apparatus of claim 4, wherein the elevators that are consuming power receive power from the capacitors to execute the plan to handle.

6. The apparatus of claim 4, wherein the elevators that are consuming power use kinetic energy to execute the plan to handle.

7. The apparatus of claim 1, wherein:

the elevator(s) comprise a load weighing device and a speed measuring device; and

,

the energy calculator is connected to the load weighing device and speed measuring device of the elevator(s), and receives information on the load from the load weighing device and the speed and direction from the speed measuring device.

8. The apparatus of claim 1, wherein:

the energy calculator comprises a map of the floors in the building, a counterweight ratio of elevator, and a plurality of energy consumption parameters for the elevator(s).

9. The apparatus of claim 1, wherein:

the total energy of the system comprises energy being regenerated by the elevator(s) moving in the direction of gravity; and

,

the energy needed to handle a power outage comprises energy needed to move the elevator(s) moving in the direction opposite gravity to a floor in the building.

10. The apparatus of claim 1, wherein the energy calculator comprises a plurality of rules for determining the plan to prepare, the rules comprising:

if the total energy in the elevator system is greater than the total energy required to handle a power outage, move an empty elevator down;

if the total energy in the elevator system is less than the total energy required to handle a power outage, move an empty elevator up, reduce the speed of an empty elevator that is consuming energy and/or reduce the speed of an occupied elevator that is consuming energy.

11. The apparatus of claim 1, wherein the plan to prepare comprises any one or more of:

a command to move an empty elevator down;

a command to move an empty elevator up;

a command to reduce the speed of an empty elevator; and

,

a command to reduce the speed of an occupied elevator.

12. The apparatus of claim 1, wherein the energy calculator comprises a plurality of handling rules for determining the plan to handle, the rules comprising:

an elevator that is empty and consuming power will be stopped;

an elevator that is moving in the direction of gravity will be stopped at the furthest floor in its direction of travel; and

an occupied elevator that is moving in a direction opposite of gravity will be stopped at the next floor in its direction of travel.

13. The apparatus of claim 1, wherein the plan to handle comprises a speed for the elevator(s) and a destination for the elevator(s).

14. The apparatus of claim 1, further comprising an uninterruptible power source connected to and providing power to the energy calculator and the movement controller.

15. The apparatus of claim 14, wherein the uninterruptible power source comprises an inverter and one or more batteries.

16. A method of handling power outages in an elevator system comprising:

calculating the total energy in the elevator system and the total energy required to handle a power outage;

preparing a plan to prepare and a plan to handle;

executing the plan to prepare if there is no power outage; and

executing the plan to handle if there is a power outage.

17. A method of evacuating building occupants in the event of a power outage using an elevator system-comprising the steps of:

permitting building occupants to load one or more elevators up to load capacity;

assessing a position and a load for the elevators in the elevator system;

preparing an optimum evacuation plan to evacuate elevators having a load sufficient to regenerate power, and to evacuate elevators having an insufficient load by consuming regenerated power;

using a movement controller to execute the evacuation plan;

monitoring a voltage on a common direct current bus connected to the elevators;

adjusting the speed of moving elevators to handle any variation in the voltage on the common direct current bus;

permitting building occupants to exit elevators once the evacuation plan is complete;

using a movement controller to dispatch empty elevators upwards; and

repeating the above steps until no elevators have a sufficient load to regenerate power.

18. The method of claim 17, further comprising the steps of:

using the energy remaining in the system to supply power to evacuate elevators that do not have a sufficient load to regenerate power; and

,

repeating the above step until there is not enough energy left in the system to evacuate an elevator in the elevator system.

19. An apparatus for evacuating building occupants in the event of a power outage using an elevator system, the apparatus comprising:

one or more elevators having a load of zero to capacity;

an energy calculator connected to the elevators and capable of determining a total energy of the elevator system, a total energy required to evacuate elevators having a load greater than zero, and a plan to evacuate; and

a movement controller connected to the elevator(s) and the energy calculator, wherein the movement controller receives the plan to evacuate, and the movement controller executes the plan to evacuate.

20. The apparatus of claim 19, wherein:

the elevator(s) comprise a variable speed drive and a direct current bus;

a common direct current bus is connected to the direct current bus of each elevator such that the variable speed drive of each elevator supplies power to the direct current bus when the elevator produces energy and consumes power from the direct current bus when the elevator consumes energy; and

the movement controller is connected to the variable speed drive of the elevator(s) and executes the plan to evacuate by controlling the variable speed drive of the elevator(s).

21. The apparatus of claim 20, wherein one or more capacitors are connected to the common direct current bus.

22. The apparatus of claim 20 or 21, wherein the elevators that are consuming power receive power from the common direct current bus to execute the plan to evacuate.

23. The apparatus of claim 21, wherein the elevators that are consuming power receive power from the common direct current bus and the capacitors to execute the plan to evacuate.

24. The apparatus of claim 23, wherein the elevators that are consuming power use kinetic energy to execute the plan to evacuate.

25. The apparatus of claim 19, wherein:

the elevator(s) comprise a load weighing device; and

the energy calculator is connected to the load weighing device.

26. The apparatus of claim 19, wherein:

the energy calculator comprises a map of the floors in the building, a counterweight ratio of elevator, and a plurality of energy consumption parameters for the elevator(s).

27. The apparatus of claim 19, wherein the plan to evacuate comprises any one or more of:

a command to move an empty elevator up;

a command to move a loaded elevator down;

a command to reduce the speed of an empty elevator; and

a command to reduce the speed of a loaded elevator.

28. The apparatus of claim 19, further comprising an uninterruptible power source connected to and providing power to the energy calculator and the movement controller.

29. The apparatus of claim 28, wherein the uninterruptible power source comprises an inverter and one or more batteries.