Elevator control system and method of operating an elevator system

Patent metadata

Field	Value
Publication number	US-10906775-B2
Application number	US-201515752966-A
Country	US
Kind code	B2
Filing date	Aug 19, 2015
Priority date	Aug 19, 2015
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

Disclosed is an elevator control system configured to control movement of an elevator car ( 12 ) along an elevator hoistway ( 26 ) between a starting position and a destination position (L 2 ), the control system comprising a car holding position monitoring unit configured to monitor whether the elevator car ( 12 ) has moved upwards or downwards in the hoistway ( 26 ) during a holding period ( 68 ) where the car ( 12 ) was intended to remain stationary at the destination position (L 2 ). The car holding position monitoring unit is configured to: Receive a first trigger signal ( 62 ) from a first car position reference system ( 40 ); upon receipt of the first trigger signal, receive signals from a further car position reference system to detect a first indicator ( 66 ) indicative of a travel distance (X 2 ) between the position of the elevator car ( 12 ) in the hoistway ( 26 ) when receiving the first trigger signal ( 62 ) and the position of the elevator car ( 12 ) in the hoistway ( 26 ) when stopping at the destination position (L 2 ); upon receipt of a further service call for the elevator car ( 12 ), receive further signals from the further car position reference system and receive a second trigger signal ( 70 A) from the first car position reference system ( 40 ) to detect a second indicator ( 74 A) indicative of a travel distance between the position of the elevator car ( 12 ) in the hoistway ( 26 ) at the end of the holding period ( 68 ) and the position of the elevator car ( 12 ) in the hoistway ( 26 ) when the elevator car ( 12 ) receives the second trigger signal ( 72 A) from the first car position reference system ( 40 ); and detect whether the elevator car ( 12 ) has moved during the holding period ( 68 ) based on a comparison of the first indicator ( 66 ) and the second indicator ( 74 A).

First claim

The invention claimed is:

1. An elevator control system configured to control movement of an elevator car ( 12 ) along a hoistway ( 26 ) between a starting position and a destination position (L 2 ), the control system comprising a car holding position monitoring unit configured to monitor whether the elevator car ( 12 ) has moved upwards or downwards in the hoistway ( 26 ) during a holding period ( 68 );
the car holding position monitoring unit being configured to:
receive a first trigger signal ( 62 ) from a first car position reference system ( 40 ),
upon receipt of the first trigger signal ( 62 ), receive a signal from a further car position reference system to detect a first indicator ( 66 ) indicative of the travel distance (X 2 ) between the position of the elevator car ( 12 ) in the hoistway ( 26 ) when receiving the first trigger signal ( 62 ) and the position of the elevator car ( 12 ) in the hoistway ( 26 ) when stopping at the destination position ( 64 ),
upon receipt of a further service call for the elevator car ( 12 ), receive a further signal from the further car position reference system and a second trigger signal ( 72 A, 72 B) from the first car position reference system ( 40 ) to detect a second indicator ( 74 A, 74 B) indicative of a travel distance between the position of the elevator car ( 12 ) in the hoistway ( 26 ) at the end of the holding period ( 68 ) and the position of the elevator car ( 12 ) in the hoistway when the elevator car ( 12 ) receives the second trigger signal ( 72 A, 72 B) from the first car position reference system ( 40 ); and
detect whether the elevator car ( 12 ) has moved during the holding period ( 68 ) based on a comparison of the first indicator ( 66 ) and the second indicator ( 74 A, 74 B).

2. The elevator control system according to claim 1 , wherein the car holding position monitoring unit is configured to detect that the elevator car ( 12 ) has moved in the hoistway ( 26 ) during the holding period ( 68 ) in case a difference between the first indicator ( 66 ) and the second indicator ( 74 A, 74 B) differs from a predetermined difference.

3. The elevator control system according to claim 1 , wherein the first car position reference system ( 40 ) is a hoistway-based car position reference system.

4. The elevator control system according to claim 3 , wherein the first car position reference system ( 40 ) comprises a plurality of switching elements ( 44 , 46 , 48 ) configured to interact with a sensor ( 42 ) mounted to the elevator car ( 12 ), each of the switching elements ( 44 , 46 , 48 ) being positioned at a predetermined position (L 1 , L 2 , L 3 ) along the hoistway ( 26 ).

5. The elevator control system according to claim 1 , wherein the destination position (L 2 ) is a landing position (L 1 , L 2 , L 3 ) in the hoistway ( 26 ) and the first car position reference system ( 40 ) is a landing position reference system.

6. The elevator control system according to claim 5 , wherein receiving the first trigger signal ( 62 ) indicates that the elevator car ( 12 ) is approaching the destination landing (L 2 ) and receiving the second trigger signal ( 72 A, 72 B) indicates that the elevator car ( 12 ) has left the destination landing (L 2 ).

7. The elevator control system according to claim 1 , wherein the further position reference system is a machine-based car position reference system configured to detect movement of at least one component ( 30 , 34 , 36 , 38 ) of a hoist machine ( 18 ) driving the elevator car ( 12 ).

8. The elevator system according to claim 7 , wherein the further position reference system detects rotation of the traction sheave ( 36 ) or drive motor ( 30 ).

9. The elevator control system according to claim 1 , being configured to suppress opening the car doors and/or landing doors in case it is detected that the elevator car ( 12 ) has moved in the hoistway ( 26 ) during the holding period ( 68 ) by an offset distance equal to or larger than a predetermined threshold.

10. The elevator control system according to claim 9 , being configured to perform a correction movement of the elevator car ( 12 ) in the hoistway ( 26 ) before opening the car doors and/or the landing doors.

11. The elevator control system according to claim 1 , being configured to evaluate the offset distance of the elevator car ( 12 ) during the holding period ( 68 ) as a function of the duration of the holding period ( 68 ).

12. An elevator system ( 10 ) comprising a hoist machine ( 18 ), a tension member ( 16 ) coupled to the hoist machine ( 18 ) and to an elevator car ( 12 ), such as to move the elevator car ( 12 ) in vertical direction between landings (L 1 , L 2 , L 3 ), and an elevator control system according to claim 1 .

13. The elevator system ( 10 ) according to claim 12 , wherein the elevator system ( 10 ) is a traction drive elevator system comprising a hoist machine ( 18 ) having a traction sheave ( 36 ) rotationally coupled to a drive motor ( 30 ), the tension member ( 16 ) running over the traction sheave ( 36 ) and frictionally engaging a traction surface ( 38 ) of the traction sheave ( 36 ) in its section running over the traction sheave ( 36 ); the elevator system ( 10 ) further comprising a holding brake ( 32 ) engaging the hoist machine ( 18 ) for holding the elevator car ( 12 ) at a desired position.

14. A method of controlling movement of an elevator car ( 12 ) along a hoistway ( 26 ) between a starting position and a destination position (L 2 ), the method comprising monitoring whether the elevator car ( 12 ) has moved upwards or downwards in the hoistway ( 26 ) during a holding period ( 68 ) by carrying out the following:
receiving a first trigger signal ( 62 ) from a first car position reference system ( 40 ),
upon receipt of the first trigger signal, receiving signals from a further car position reference system to detect a first indicator ( 66 ) indicative of a travel distance (X 2 ) between the position of the elevator car ( 12 ) in the hoistway ( 26 ) when receiving the first trigger signal ( 62 ) and the position of the elevator car ( 12 ) in the hoistway ( 26 ) when stopping at the destination position ( 64 ),
upon receipt of a further service call for the elevator car ( 12 ), receiving further signals from the further car position reference system and receiving a second trigger signal ( 72 A) from the first car position reference system ( 40 ) to detect a second indicator ( 74 A) indicative of a travel distance between the position of the elevator car ( 12 ) in the hoistway ( 26 ) at the end of the holding period ( 68 ) and the position of the elevator car ( 12 ) in the hoistway ( 26 ) when the elevator car ( 12 ) receives the second trigger signal ( 72 A) from the first car position reference system ( 40 ); and
detecting whether the elevator car ( 12 ) has moved during the holding period ( 68 ) based on a comparison of the first indicator ( 66 ) and the second indicator ( 74 A).

15. The method according to claim 14 , further comprising:
detecting that the elevator car ( 12 ) has moved in the hoistway ( 26 ) during the holding period ( 68 ) in case a difference between the first indicator ( 66 ) and the second indicator ( 70 A) differs from a predetermined difference.

16. The method according to claim 14 , wherein the destination position (L 2 ) is a landing position (L 1 , L 2 , L 3 ) in the hoistway ( 26 ), the first car position reference system ( 40 ) is a landing position reference system, and receiving the first trigger signal ( 62 ) indicates that the elevator car ( 12 ) is approaching the destination landing (L

Assignees

• Schoenauer Uwe
• Otis Elevator Co

Inventors

• Schoenauer Uwe

Classifications

• B66B5/0037 Primary

  Performance analysers · CPC title

• B66B1/3492

  Position or motion detectors or driving means for the detector (B66B1/40, B66B1/50 take precedence; length measuring G01B; speed measuring G01P) · CPC title

• B66B1/28

  electrical (detecting excessive speed B66B5/04 {; control of electrical motor H02P}) · CPC title

• B66B1/36

  Means for stopping the cars, cages, or skips at predetermined levels · CPC title

• B66B5/0018 Primary

  Devices monitoring the operating condition of the elevator system · CPC title