DETECTION SYSTEM FOR AN ABNORMAL SITUATION DURING ELEVATOR OPERATION

Abstract

The invention concerns a method, system and computer program for monitoring the run of a roping interconnecting a car and a counterweight of an elevator and for detecting an abnormal operation condition during the drive of a traction sheave intending therewith the car and the counterweight to be moved via said roping. Said roping is running on its way from the car to the traction sheave via at least one pulley and on its way from the counterweight to the traction sheave via at least one pulley, wherein the rotation of said at least two pulleys is monitored by sensing their rotation. These rotation data are then analysed in view of a mutual correlation indicating therewith a synchronized run of the roping on either side of the traction sheave, and detecting therewith an abnormal situation when detecting an absence of such correlation.

Claims

1. A method for monitoring the run of a roping interconnecting a car and a counterweight of an elevator and for detecting an abnormal operation condition during the drive of a drive pulley intending therewith the car and the counterweight to be moved by said roping, wherein the roping runs from the car to the drive pulley via at least one diverting pulley and from the counterweight to the traction drive pulley via at least one diverting pulley, said method comprising the steps of: monitoring the rotation of at least two of said pulleys by sensing rotation thereof; and analysing rotation data in view of a mutual correlation indicating unobstructed advancing of the car or counterweight or both, and detecting therewith an abnormal situation when detecting an absence of such correlation.

2. The method according to claim 1, wherein a stopping of the run of the elevator is initiated as a response of an abnormal difference in the mutual rotation data.

3. The method according to claim 1, further comprises further comprising the step of launching an alarm as a response to a detected abnormal operation condition.

4. A computer program comprising a program code embodied on a non-transitory computer readable medium and adapted to cause the method according to claim 1 to be executed on a data-processing system.

5. A system for monitoring the run of a roping interconnecting a car and a counterweight of an elevator and for detecting an abnormal operation condition during the drive of a drive pulley intending therewith the car and the counterweight to be moved by said roping, the system comprising: at least one diverting pulley coupled to the car, the drive pulley and at least one diverting pulley coupled to the counterweight, wherein the at least two pulleys are equipped with sensors sensing rotation thereof, respectively; and a control unit configured to receive the sensor data and to analyse the sensor data by monitoring a mutual correlation indicating therewith unobstructed advancing of the car or counterweight or both.

6. The system according to claim 5, wherein the system is configured to stop the run of the elevator as a response of the detection of an abnormal difference in the mutual correlation.

7. The system according to claim 5, wherein the system is configured to launch an alarm as a response to a detected abnormal difference in the mutual correlation.

8. The method according to claim 2, further comprising launching an alarm as a response to a detected abnormal operation condition.

9. A computer program comprising a program code embodied on a non-transitory computer readable medium and adapted to cause the method according to claim 2 to be executed on a data-processing system.

10. A computer program comprising a program code embodied on a non-transitory computer readable medium and adapted to cause the method according to claim 3 to be executed on a data-processing system.

11. The system according to claim 6, wherein the system is configured to launch an alarm as a response to a detected abnormal difference in the mutual correlation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The FIGURE illustrates the elevator system according to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] The invention is now described in more detail by taking reference to the enclosed drawing. Therein, The FIGURE shows the inventive concept. The elevator system shown includes an elevator car 10 being suspended by a roping 13 which roping is guided over a traction sheave 14 to reach and suspend the counterweight 12. The roping is guided over pulley1 16, pulley2 17 both belonging to the elevator car, while there is a further pulley3 18 belonging to the counterweight. As soon as the roping is moving for raising or lowering the car, there is inherently a rotation of each of the pulleys 16, 17, 18 that is linked to such movement. This means that each pulley 16, 17, 18 is showing a characteristic angle-distance running over as soon as the roping travels over the pulleys, respectively. In other words, there is a velocity v1 for pulley1 16, there is a velocity v2 for pulley2 17 and there is a velocity v3 for pulley3 18. Although being dependent from the size of the respective pulley there can be nevertheless a comparison between all these running-values with each other so that in a normal operation specific data must be provided from each pulley to know about a correct run of the roping. This means that, in case all pulleys, i.e. pulley1, pulley2 and pulley3 are of the same size, there must be the same velocity and the same rotational angle-distance for all of them as long as the elevator is running correctly. As soon as a match between the speeds of the pulleys or the rotated distances, respectively, can no longer be determined, a stalling situation can be identified that indicates that either the car or counterweight is not advancing freely.

[0027] Therewith, an emergency situation can be triggered by starting an alarm or even by stopping the run of the elevator.

[0028] At least, the rotation of the traction sheave 14 can be included into the comparison-process by adding its torque or the energy consumption by means of the current needed to evaluate whether a normal operation is present or not.

[0029] Reference Numerals:

[0030] 10 elevator car

[0031] 12 counterweight

[0032] 13 roping

[0033] 14 traction sheave

[0034] 16 pulley1

[0035] 17 pulley2

[0036] 18 pulley3