Method for transmitting messages in an elevator communications system

• US 5,551,532 A
• Filed: 02/28/1994
• Issued: 09/03/1996
• Est. Priority Date: 02/28/1994
• Status: Expired due to Fees

• Current Assignee: Otis Elevator Company (Otis Worldwide Corp.)
• Original Assignee: Otis Elevator Company (Otis Worldwide Corp.)
• Inventors: Kupersmith, Bertram F.
• Primary Examiner(s): NAPPI, ROBERT E
• Application Number:
  US08/203,139
• Time in Patent Office: 918 Days
• Field of Search: 187/391, 187/393, 187/247, 187/248, 340/825.01, 340/825.05, 371/11.1, 371/11.2, 371/20.1, 371/20.6
• US Class Current: 187/391
• CPC Class Codes: B66B 1/2458 For elevator systems with multiple shafts and a single car per shaft
• CPC Class Codes: B66B 1/34 Details , e.g. call counting devices, data transmission from car to control system, devices giving information to the control system
• CPC Class Codes: B66B 1/3415 Control system configuration and the data transmission or communication within the control system
• CPC Class Codes: B66B 1/3423 Control system configuration, i.e. lay-out
• CPC Class Codes: B66B 1/3438 Master-slave control system configuration
• CPC Class Codes: B66B 1/3446 Data transmission or communication within the control system
• CPC Class Codes: B66B 2201/233 Periodic re-allocation of call inputs

Abstract

In a two-way ring elevator communications system, characterized in that a controller is associated with each elevator to process inter-elevator messages and the controllers of the elevators are linked together in serial fashion on a two-way communications system so that the messages of each controller are passed along to and processed by each of the other controllers in two directions on two independent rings, whichever of the two rings is properly functioning is used at full capacity but if neither ring is properly functioning then both rings are operated at reduced capacity, the reduction being carried out by reducing the time between reassignments of elevator hall calls.

Claims

1. A method for transmitting messages in an elevator communications system comprising:

providing a two-way ring communications system including a plurality of elevator controllers, said elevator controllers being peers in that none has exclusive control over the operation of the others, each elevator controller providing two serial asynchronous full duplex I/O channels to communicate with the next and previous elevator controllers, each elevator controller having three remote serial link interfaces including one to elevator fixtures, elevator buttons and elevator tell tale lights, another interface to elevator-related hall fixtures and hall lanterns, and a third interface for group-related hall fixtures, hall buttons and hall lights;

checking operation of a first ring of said two-way elevator ring communications system including transmitting from an originating elevator controller a status message to see if said status message is received by said originating elevator controller after traveling around said ring and providing a first-ring-good signal if the status message is received at the originating controller within a watchdog time after traveling around said first ring and providing a first-ring-bad signal if said status message is not received by said originating elevator controller within said watchdog time after traveling around said first ring;

checking the operation of a second of said two-way elevator communications ring system including transmitting a second status message around the ring to see if said second status message is received by said originating elevator controller afar traveling around said second ring and providing a second-ring-good signal if the second status message is so received within said watchdog time and a second-ring-bad signal if said second status message is not so received by said originating elevator controller within said watchdog time;

transmitting on said first ring in response to said first-ring-good signal;

transmitting on said second ring in response to said second-ring-good signal;

transmitting messages on both rings in response to said first-ring-bad signal and second-ring-bad signal; and

varying a reassignment time at which assignment of hall calls to elevators is decided, wherein said varying step is provided in response to both said first-ring-bad signal and second-ring-bad signal.

2. A method for transmitting messages in an elevator communications system, comprising:

providing a two-way ring communications system including a plurality of elevator controllers, said elevator controllers being peers in that none has exclusive control over the operation of the others, each elevator controller providing two serial asynchronous full duplex I/O channels to communicate with the next and previous elevator controllers, each elevator controller having three remote serial link interfaces including one to elevator fixtures, elevator buttons and elevator tell tale lights, another interface to elevator-related hall fixtures and hall lanterns, and a third interface for group-related hall fixtures, hall buttons and hall lights;

checking operation of a first ring of said two-way elevator ring communications system including transmitting from an originating elevator controller a status message to see if said status message is received by said originating elevator controller after traveling around said ring and providing a first-ring-good signal if the status message is received at the originating controller within a watchdog time after traveling around said first ring and providing a first-ring-bad signal if said status message is not received by said originating elevator controller within said watchdog time after traveling around said first ring;

checking the operation of a second ring of said two-way elevator communications ring system including transmitting a second status message around the ring to see if said second status message is received by said originating elevator controller after traveling around said second ring and providing a second-ring-good signal if the second status massage is so received within said watchdog time and a second-ring-bad signal if said second status message is not so received by said originating elevator controller within said watchdog time;

transmitting on said first ring in response to said first-ring-good signal;

transmitting on said second ring in response to said second-ring-good signal; and

transmitting messages on both rings in response to said first-ring-bad signal and second-ring-bad signal;

varying a reassignment time at which assignment of hall calls to elevators is decided, wherein said varying step is provided in response to both said first ring bad signal and second ring bad signal and said reassignment time is varied as a function of the number of elevator controllers communicating on both said first and second ring, and the number of elevator stops available.

3. A method for transmitting messages in an elevator communications system, comprising:

providing a two-way ring communications system including a plurality of elevator controllers, said elevator controllers being peers in that none has exclusive control over the operation of the others, each elevator controller providing two serial asynchronous full duplex I/O channels to communicate with the next and previous elevator controllers, each elevator controller having three remote serial link interfaces including one to elevator fixtures, elevator buttons and elevator tell tale lights, another interface to elevator-related hall fixtures and hall lanterns, and a third interface for group-related hall fixtures, hall buttons and hall lights;

checking operation of a first ring of said two-way elevator ring communications system including transmitting from an originating elevator controller a status message to see if said status message is received by said originating elevator controller after traveling around said ring and providing a first-ring-good signal if the status message is received at the originating controller within a watchdog time after traveling around said first ring and providing a first-ring-bad signal if said status message is not received by said originating elevator controller within said watchdog time after traveling around said first ring;

checking the operation of a second ring of said two-way elevator communications ring system including transmitting a second status message around the ring to see if said second status message is received by said originating elevator controller after traveling around said second ring and providing a second-ring-good signal if the second status message is so received within said watchdog time and a second-ring-bad signal if said second status message is not so received by said originating elevator controller within said watchdog time;

transmitting only on said first ring in response to said first-ring-good signal;

transmitting only on said second ring in response to said first-ring-bad signal and said second-ring-good signal; and

transmitting messages on both rings in response to said first-ring-bad signal and second-ring-bad signal.

4. The method of claim 3, further including the step:

varying a reassignment time at which assignment of hall calls to elevators is decided, wherein said varying step is provided in response to both said first-ring-bad signal and second-ring-bad signal.

5. The method of claim 4, wherein said reassignment time is varied as a function of the number of elevator controllers communicating on said first and second ring, and the number of elevator stops available.