Elevator system and method for operating elevator system

Abstract

The invention relates to an elevator system (1) comprising: a hoistway (4) having a marking object (18) arranged at a predetermined position in the hoistway; an elevator car (2) having a sensor (16) that provides an indication when the elevator car (2) reaches the position of the marking object (18); a supplemental positioning system providing a supplemental indication of the position of the elevator car (2) in the hoistway (4); and a controller (12) that receives the indication and supplementation indication. In order to minimize the need for manual checks, the controller (12) comprises a memory (29) that maintains a set position (18) for each marking object and, during operation of the elevator, stores the set position (18) for each marking object. The controller is configured to calculate an offset of the marking object (18) for which the sensor (16) provides the indication by comparing a set position of the marking object (18) in question with a position indicated by the supplementary positioning system at the indication of the marking object (18), and to trigger an alarm if the calculated offset satisfies a predetermined criterion.

Description

Technical Field

[0001] The present invention relates to an elevator system and a method for operating an elevator. More precisely, the present invention relates to the problem of ensuring that an elevator system is able to track the position of an elevator car. Background Art

[0002] In order to operate the elevator in a safe manner, the elevator system needs to know the position of the elevator car. A previously known solution is to provide the hoistway with marking objects at predetermined positions in the hoistway. Sensors on the elevator car are then able to detect and provide an indication when the elevator car reaches the position of the marking object.

[0003] Since the marking object and the sensor only provide an indication of the position of the elevator car when the elevator car is located at the marking object, previously known elevator systems are additionally provided with a supplementary positioning system. In this way, the position of the elevator car is known, regardless of where the elevator car is located in the elevator shaft.

[0004] There are alternative ways to implement supplemental positioning systems. However, a common problem is that supplemental positioning systems are not accurate enough in all cases. Therefore, supplemental positioning systems are used in combination with marker objects and sensors.

[0005] Naturally, the exact position of the elevator car in the hoistway is a critical safety issue. Therefore, a lot of effort is required to ensure that the positioning works correctly. Therefore, regular manual checks are required. Summary of the invention

[0006] The object of the present invention is to solve the above mentioned drawbacks and to provide a solution which facilitates automatic monitoring. This object is achieved by an elevator system according to independent claim 1 and a method according to independent claim 11.

[0007] By maintaining a set position for each marking object and by calculating the offset during elevator operation by comparing the set position with the position indicated by the supplementary positioning system when an indication of a marking object is received, it is possible to detect when the calculated offset meets a predetermined criterion for triggering an alarm. This facilitates easy and reliable automatic monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In the following, the present invention will be described in more detail by way of examples and with reference to the accompanying drawings, in which:

[0009] Figure 1 shows an elevator system,

[0010] Figure 2 and Figure 3 A rotating element with an encoder implemented together with a hoisting rope pulley of an elevator car is shown, and

[0011] Figure 4 A rotating element with an encoder implemented with a roller guide of an elevator car is shown. DETAILED DESCRIPTION

[0012] Figure 1 An elevator system 1 is shown, in which a method for operating an elevator can be carried out.

[0013] exist Figure 1 In the example shown, an elevator car 2 moves, for example, in a hoistway 4 between landings 3 with doors, which are located on different floors 5 of a building. In the example shown, the elevator car 2 is moved by a hoisting machine 6 with the aid of ropes 7. The same ropes are also used to move a counterweight 8 in the hoistway 4.

[0014] The hoist 6 comprises an electric motor 9 which drives a wheel 11 via a shaft 10, around which a rope 7 runs. In the example shown, the operation of the elevator system is controlled by a controller 12 comprising one or more components. These components may be arranged in a single device cabinet, as shown in the example, or alternatively distributed in different locations around the elevator installation site. For example, the illustrated controller may be implemented by circuits, by one or more processors running program code, or as a combination of these.

[0015] exist Figure 1 In the embodiment, the electric motor 9 of the hoist 6 is controlled by a motion controller 13, which may include a plurality of components, including a frequency converter for supplying power to the electric motor 9. Figure 1 In the example shown, the controller 12 may include a main safety circuit 14, which may be implemented, for example, as a programmable electronic controller running safety monitoring software that monitors the operation of the entire elevator system. The main safety circuit 14 may receive signals from a plurality of components in the elevator system 1, and it may control the electromechanical brakes and the emergency brake of the hoist, for example, so that the emergency brake can be activated when necessary.

[0016] In order to be able to correctly move the elevator car 2 in the hoistway 4 during elevator operation, the controller 12 (such as the motion controller 13) requires information on the positioning of the elevator car 2 in the hoistway 4. For this purpose, Figure 1 The elevator system is provided with a relative positioning system and a supplementary positioning system.

[0017] The relative positioning system includes a plurality of marking objects 18 arranged at predetermined positions in the hoistway 4. Typically, the marking objects 18 are arranged at least at the position of the landing 3. In addition, the marking objects 18 can be arranged at selected positions near the end of the elevator hoistway 4 to give an indication of the extreme limit of the allowable movement of the elevator car 2 in the elevator hoistway. An alternative is that the marking objects 18 are magnets, and the elevator car is provided with a sensor 16, which provides an indication to the controller 12 when the elevator car 2 has reached the position of the magnet. In any case, the relative positioning system only provides an indication of the position of the elevator car when the sensor 16 is located at one of the marking objects 18. At this stage, the controller 12 will know at which of the marking objects 18 the elevator car is located.

[0018] exist Figure 1 , the marking object 18 of the landing 3 and the sensor 16 of the elevator car 2 are positioned so that the sensor provides an indication when the floor of the elevator car 2 is correctly aligned, in other words, at the same level as the floor 5 of the landing 3. The motion controller 13 receives an indication from the sensor 16, thanks to which the elevator car 2 can be stopped at the right moment to facilitate loading and unloading of the passengers of the elevator car via the doors at the landing 3.

[0019] exist Figure 1 In the embodiment shown, the elevator system 1 is provided with five different supplementary positioning systems, but in practice it is sufficient to provide only one supplementary positioning system in the elevator system at a time. Each of the supplementary positioning systems shown provides a supplementary indication of the position of the elevator car 2 to the controller. Thus, although the relative positioning system only provides a position indication when the sensor 16 is located at the marking object 18, the motion controller 13 of the controller 12 can continuously track the position of the elevator car, regardless of where the elevator car 2 is located in the hoistway 4, thanks to the additional information from the supplementary positioning systems.

[0020] Figure 1 The first supplementary positioning system implemented in the embodiment comprises an encoder 15 combined with a rotating element in the form of a rope pulley 17, which rotates when the hoisting machine 6 ropes 7 and the elevator car 2 move in the hoistway 4. Figure 2 and Figure 3 The bottom of the sling 20 of the elevator car 2 is provided with a rope pulley 17 via which the hoisting machine ropes are guided. Figure 3One of these rope pulleys is shown in cross section. Encoder 15 includes a stationary part, for example, attached to the sling 20 and a movable part that rotates with the pulley 17. In the case of a magnetic encoder, the moving part can be a magnetic belt and the stationary part is a magnetic reader. However, other types of encoders, such as optical encoders, can also be used. In any case, when the pulley 17 rotates, the encoder provides an indication of the rotation by generating pulses. By counting the number of pulses, the amount of rotation and the travel distance of the elevator car can be calculated. This calculation can be implemented by the motion controller 13, for example, in order to provide the controller 12 with a supplementary position of the elevator car 2 based on the incremental travel distance indicated by the encoder.

[0021] also, Figure 1 The second complementary positioning system implemented in comprises an encoder 15 combined with a rotating element, however, the encoder 15 is located in or connected to the hoist 16. In this embodiment, the rotating element can be a wheel 11 or a shaft 10 of the hoist 6, which rotates when the electric motor 9 rotates the wheel 11 via the shaft 10 to move the rope 7 and the elevator car 2. Similarly, as combined with Figure 2 and Figure 3 As explained, the encoder 15 generates pulses that can be counted to determine the position of the elevator car in the hoistway 4.

[0022] also, Figure 1 The third supplementary positioning system in comprises an encoder 15 combined with a rotating element, however, the rotating element is in the form of a rope pulley 21 of an overspeed governor. The overspeed governor is used to ensure that the speed of the elevator car does not exceed a predetermined limit. If the predetermined limit is exceeded, an emergency brake can be triggered. Figure 1 In the embodiment, the rope 22 of the overspeed limiter is connected to the elevator car 2, and the rope 22 is guided from the elevator car 2 around the rope pulley 21. Therefore, when the elevator car 2 and the rope 22 move, the pulley 21 rotates. Figure 2 and Figure 3 As explained, the encoder 15 generates pulses that can be counted to determine the position of the elevator car in the hoistway 4.

[0023] also, Figure 1 The fourth supplementary positioning system in the embodiment comprises an encoder 15 combined with a rotating element, however, the rotating element is in the form of a roller guide 24 of the elevator car 2. The roller guide 24 is Figure 4 When the elevator car 2 moves in the hoistway 4, the roller guide 24 rotates due to contact with the guide rail 23 installed in the hoistway 4. Figure 2 and Figure 3 As explained, the encoder 15 generates pulses that can be counted to determine the position of the elevator car in the hoistway 4.

[0024] at last, Figure 1 A fifth supplemental positioning system in comprises an acceleration sensor provided to the elevator car 2. Thus, as the elevator car moves, the acceleration sensor 25 can provide a signal to the motion controller 13 to provide a supplemental indication of the position of the elevator car 2 to the controller.

[0025] No matter which of the above-mentioned supplementary positioning systems is used in the elevator system, there is always a certain degree of inaccuracy in the supplementary indication of the position. The reason is that slippage may occur at the rotating elements, such as the slippage of the rope 7, 22 relative to the pulley 17, 21 or the wheel 11, or the slippage of the roller guide 24 relative to the guide rail 23. When using acceleration sensors, a certain degree of inaccuracy can also be expected. Therefore, the supplementary positioning system needs to be used in combination with the relative positioning system, so that when the sensor has provided an indication of the marking object, the exact position will be known at each moment, and the position of the elevator car when it moves between the marking objects is obtained from the supplementary positioning system.

[0026] However, inaccuracies may also occur to the relative positioning system when, for example, one or more of the marker objects 18 may become misaligned over time. Alternatively, it is possible that a marker object may become damaged and require replacement.

[0027] Thus, the controller 12 maintains a set position for each marker object 18 in the memory 29. During operation of the elevator 2, the controller 12 is configured to calculate the offset of the marker object 18 for which the sensor 16 provides an indication. At the moment of indicating a marker object 18, the offset is calculated by comparing the set position of the marker object in question obtained from the memory 29 with the position indicated by the currently used supplementary positioning system. If the marker object 18 has moved, the offset value will indicate how much the marker object has moved compared to the set position. On the other hand, if the marker object has not moved since the set position, the offset of this marker object will be zero.

[0028] In the event that the calculated offset meets predetermined criteria, for example when the offset value is high and indicates that the marker object has moved a greater distance than the offset value allows, the controller 12 will trigger an alarm. At this stage, the alarm may be triggered so that further elevators are prevented from running with the elevator car until maintenance personnel inspect the elevator in question.

[0029] In practice, the elevator system can also utilize the calculated offset value to improve the positioning accuracy, although the criterion for triggering an alarm has not yet been met. An alternative is to use the offset value of a specific marker object 18 to assess when the elevator car is close to the marker object. Thus, instead of assuming that the elevator is at the marker object when the supplementary positioning system indicates that the supplementary position of the elevator car corresponds to the set position for the marker object stored in the memory 29, the last calculated offset value for the marker object can be taken into account. In this way, it is possible to estimate with better accuracy when the elevator car has reached the position of the marker object based on the obtained supplementary position.

[0030] The controller 12 can be configured to store the calculated offset values ​​in the memory individually for each marker object 18 also when no alarm is triggered. In this way, once the alarm is triggered, the controller can process the stored offset values, and based on the result of the processing, an alarm can be triggered with an indication of the type of error detected. If a high offset value is calculated for only one of the marker objects 18 when the alarm is triggered, it is likely that only one of the marker objects 18 has moved a longer distance than allowed. In this case, the alarm can be triggered with the indication of a single misplaced marker object 18. However, if high offset values ​​have been calculated for multiple marker objects 18, an alarm can be triggered, indicating an error in the supplemental positioning system.

[0031] exist Figure 1 In the embodiment of the present invention, it is assumed, as an example, that the elevator system has an interface 26 to a communication system for sending messages to a predetermined receiver, which can be located outside the installation site of the elevator. For example, the communication system can be a wired or wireless communication system, such as a mobile communication system. In this case, the triggered alarm can be transmitted from the controller 12 to a remote monitoring center 27, which monitors the operation of a plurality of elevators, for example. The monitoring center 27 can include a server or utilize a cloud service to store incoming messages, so that maintenance personnel can utilize a portable terminal 28 to, for example, check the status of the monitored elevator equipment. Alternatively or additionally, for example, the message with the alarm can be sent directly to the terminal 28 of the maintenance personnel.

[0032] In addition to sending when an alarm has been triggered, the controller 12 may also send data to a predetermined receiver in other circumstances.An alternative is to periodically transmit information about the calculated offset values ​​so that maintenance personnel have this information available when considering and evaluating the maintenance needs of the elevator in question.

[0033] when Figure 1When an elevator system of the type 200 is put into use for the first time and also after maintenance involving adjustments, it is beneficial to implement a setting procedure to ensure that the set position of the marking object 18 is correctly stored in the memory 29. This can be achieved by moving the elevator car 2 from the position of the marking object to a position where the sensor 16 receives an indication that the elevator car has reached the position of the subsequent marking object 18 during the setting period. At this stage, a supplementary indication provided by the supplementary positioning system used is received. This position received from the supplementary positioning system is then stored as the set position of the marking object 18 in question. The process is then repeated for all marking objects in the hoistway 4, so that the memory 29 contains the correct set positions of all marking objects indicated by the supplementary positioning system during the setting period.

[0034] It should be understood that the above description and the accompanying drawings are only intended to illustrate the present invention. It is obvious to those skilled in the art that the present invention can be changed and modified without departing from the scope of the present invention.

Claims

1. An elevator system (1), comprising: A shaft (4) having a marking object (18) arranged at a predetermined position in the shaft, An elevator car (2) having a sensor (16) which provides an indication when the elevator car (2) has reached the position of a marking object (18), a supplementary positioning system providing a supplementary indication of the position of the elevator car (2) in the hoistway (4) between the marking objects, and A controller (12), which receives the indication and the supplemental indication, is characterized in that: The controller (12) includes a memory (29) that holds a set position (18) for each marking object, and During elevator operation, the controller is configured to calculate the offset of the marking object (18) for which the sensor (16) provides an indication by comparing the set position of the marking object (18) in question with the position indicated by the supplementary positioning system at the indication of the marking object (18), and to trigger an alarm if the calculated offset meets a predetermined criterion.

2. The elevator system according to claim 1, wherein: The marking object (18) is a magnet.

3. The elevator system according to any one of claims 1 to 2, wherein: The supplemental positioning system includes a rotating element that rotates as the elevator car (2) moves in the hoistway (4), and an encoder (15) that provides an indication of the rotation of the rotating element.

4. The elevator system according to claim 3, wherein: The rotating element is a shaft (10) of a hoisting machine (6), a rope wheel (11) or a pulley (17, 21) of a hoisting machine rope (7) or an overspeed governor rope (22) which rotates when the rope moves in the hoistway during operation of the elevator car (2), or a roller guide (24) of the elevator car (2) which rotates during operation of the elevator car due to contact with a guide rail (23) in the hoistway.

5. The elevator system according to any one of claims 1 to 4, wherein: The supplementary positioning system comprises an acceleration sensor (25) provided to the elevator car (2).

6. The elevator system according to any one of claims 1 to 5, wherein: If the calculated deviation is outside the allowed tolerance, the controller (12) triggers an alarm, preventing the elevator from running with the elevator car (2).

7. The elevator system according to any one of claims 1 to 6, wherein: The controller (12) processes the offset values ​​calculated for the different marker objects and triggers an alarm indicating that the marker object (18) is misplaced if a high offset value is calculated for only one of the marker objects (18).

8. The elevator system according to any one of claims 1 to 7, wherein: The controller (12) processes the offset values ​​calculated for the different marker objects (18) and triggers an alarm indicating an error in the supplemental positioning system if a high offset value has been calculated for a plurality of marker objects.

9. The elevator system according to any one of claims 1 to 8, wherein: The elevator system comprises an interface (26) to a communication system for sending at least one of a triggered alarm and a calculated offset value to a predetermined receiver (27, 28).

10. The elevator system according to any one of claims 1 to 9, wherein: A marking object (18) is arranged in the shaft (4) at least at the position of a landing (3) so that when the sensor provides an indication that the elevator car has reached the position of the marking object at the landing, the floor of the elevator car is aligned with the floor (5) of the landing (3).

11. A method for operating an elevator, comprising: receiving an indication when the elevator car (2) has reached the location of the marking object (18), and Receiving an indication of the position of the elevator car (2) from a supplemental positioning system, the supplemental positioning system sensing the position of the elevator car (2) in the hoistway (4) between the marking objects, characterised in that the method comprises: maintaining a set position for each marking object (18) in a memory (29), When an indication of said marking object is received, calculating an offset by comparing said set position of the marking object (18) in question with the position indicated by said supplementary positioning system, and If the calculated deviation meets predetermined criteria, an alarm is triggered.

12. The method according to claim 11, wherein: If a high offset value is calculated for only one of the marker objects, an alarm is triggered to indicate that the marker object (18) is misplaced.

13. The method according to claim 11 or 12, wherein: If high offset values ​​have been calculated for a plurality of marker objects (18), an alarm is triggered indicating an error in the supplementary positioning system.

14. The method according to any one of claims 11 to 13, wherein: At least one of the alarm or the calculated offset value is sent to a predetermined receiver (27, 28) via the interface (26) and the communication system.

15. The method according to any one of claims 11 to 14, wherein: The method comprises storing a set position of a marking object (18) in the memory (29) during setting by: moving the elevator car (2) from the position of the marking object to a position where an indication is received that the elevator car (2) has reached the position of a subsequent marking object (18), receiving a supplemental indication of the position from the supplemental positioning system, the supplemental indication indicating the position of the elevator car, and The position of the elevator car (2) from the supplementary positioning system is stored in the memory (18) as the set position of the marking object (18).

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