Elevator and method for providing access to electrical safety device of elevator

Abstract

An elevator comprising: an elevator car (10) adapted to transfer passengers and / or goods between landing; an electric drive (4) for operating the elevator car; the manual operation panel (2) is arranged in the elevator shaft and used for manually driving the elevator car; an elevator safety chain (50) comprising a controller (110) connected to a plurality of safety devices for monitoring elevator safety; the safety chain comprises an electrical safety device (20, 21) configured to provide information about the access of the elevator car to the temporary refuge space; the controller is configured to obtain information from the electrical safety device and generate a stop command to stop movement of the elevator car before entering the refuge space. The controller is configured to, in response to a maintenance request for the electrical safety device, exclude the electrical safety device from operation of the elevator safety chain (50) to enable manual actuation of the elevator car with the manual operation panel. A method for providing access to an electrical safety device of an elevator.

Description

Technical Field

[0001] The invention relates to an elevator for transferring passengers and / or freight between landings in an elevator shaft, and to a method for providing access to an electrical safety device of an elevator. Background Art

[0002] In addition to the normal operating mode, the elevator may have a manual drive operating mode. The manual drive operating mode is useful, for example, in conjunction with inspection and / or maintenance operations of the elevator system. In the manual drive operating mode, normal operation is prevented and the elevator car can only be manually driven at a reduced speed (e.g., 0.3 m / s). The manual drive operating mode can be executed by continuously activating an input device, such as a button or switch in a manual operating panel. When the input device in the manual operating panel is deactivated, the movement of the elevator car stops. This means that in the manual drive operating mode, the elevator car moves only when the input device remains activated. The manual operating panel can be arranged in the elevator shaft pit or on the roof of the elevator car.

[0003] The elevator may have a safety chain configured to control elevator safety during maintenance and inspection operations. In order to improve elevator safety, a temporary refuge space may be arranged for service personnel working in the shaft. The elevator safety chain may include an electrical safety device mounted in the shaft to provide information about the elevator car approaching the temporary refuge space in the manual drive operation mode. Such an electrical safety device may be a limit switch that sets a limit on the movement of the car toward the temporary refuge space. In the manual drive operation mode, the limit switch interrupts the elevator safety chain when the car reaches the switch. This will result in the activation of the lifting machinery brake and interrupt the power supply to the lifting motor. Therefore, the elevator car movement will stop before the car enters the refuge space.

[0004] Abnormal operation of the limit switch (such as failure or installation error) can disable manual drive operation to ensure that maintenance personnel located in the shaft cannot move the car into the temporary refuge space. In this case, the movement of the car will be possible only from outside the shaft, such as by manually opening the hoisting machinery brake or using the rescue drive switch in the elevator control cabinet for rescue operation. The rescue drive switch bypasses the safety chain to achieve low-speed rescue operation of the car.

[0005] However, in order to repair said operating anomaly, the maintenance technician must access the limit switch. In many cases, this can only be achieved by working from the car roof of the elevator car located below the limit switch, which is in close proximity to the switch. All this means that repairing the limit switch can be difficult, since in practice two maintenance technicians are required to carry out the work, one to operate the rescue drive switch in the control cabinet to move the car into a suitable working position, while the other enters the shaft and stands on the roof of the moving car. Furthermore, bypassing the safety chain can also be an additional safety risk for the maintenance technician in the shaft. Summary of the invention

[0006] The object of the present invention is to solve at least one of the above problems. The present invention proposes an elevator with a novel maintenance operation function, which provides maintenance technicians with safe and easy access to electrical safety devices in the elevator shaft.

[0007] A new elevator according to claim 1 is proposed.

[0008] A new method according to claim 15 is also proposed.

[0009] Further embodiments of the invention are described in the dependent claims and in the following description.

[0010] The elevator comprises an elevator car adapted to transfer passengers and / or cargo between landings in the elevator shaft and an electric drive for operating the elevator car. The elevator may also comprise a counterweight moving in a direction opposite to the elevator car, as known in the art. According to an embodiment, the electric drive comprises an elevator hoisting machinery and an elevator drive unit. According to one embodiment, the elevator hoisting machinery comprises an elevator hoisting motor (e.g. a permanent magnet motor) and a traction sheave for hoisting ropes of the car / counterweight. According to an embodiment, the elevator drive unit comprises a frequency converter providing an electric power signal to the elevator hoisting motor.

[0011] Furthermore, the elevator comprises a manual operating panel arranged inside the elevator shaft and used for manually driving the elevator car. The manual operating panel comprises input means, such as buttons and / or switches. The low-speed manual drive can be performed by continuously activating the input means. When the input means in the manual operating panel are deactivated, the movement of the elevator car stops. This means that in the manual drive operating mode, the elevator car moves only when the input means remain activated. The manual operating panel can be arranged, for example, in the elevator shaft pit or on the roof of the elevator car.

[0012] The elevator also includes an elevator safety chain. The safety chain includes a controller connected to a plurality of safety devices (eg safety contacts) for monitoring elevator safety during maintenance and inspection operations.

[0013] The elevator safety chain comprises an electrical safety device configured to provide information about the elevator car approaching a temporary refuge space in the shaft. According to one embodiment, the electrical safety device is configured to set a limit, such as a limit switch, for the movement of the car towards the temporary refuge space. According to one embodiment, when the car reaches the limit switch in the manual drive operating mode, the limit switch opens and interrupts the safety chain. This will cause the car to stop moving before entering the refuge space.

[0014] Furthermore, the controller is configured to obtain information from the electrical safety device and generate a stop command, for example, for lifting the mechanical brake to stop the movement of the car and interrupt the low-speed manual drive before entering the refuge space. According to an embodiment, the controller is an electronic safety controller running safety software. According to an embodiment, the electronic safety controller is designed to comply with the safety specification IEC61508 and meet the safety integrity level 3 (SIL 3) of the specification.

[0015] In response to a maintenance request for the electrical safety device, the controller is configured to exclude the electrical safety device from operation of the elevator safety chain to allow manual driving of the car using the manual operating panel.

[0016] In the event that an operational anomaly (e.g., a malfunction or installation error) of an electrical safety device prevents manual driving of the car in the elevator shaft using a manual operating panel, a maintenance technician may generate a specific maintenance request for repairing the electrical safety device. According to an embodiment, the maintenance request is generated via a manual input panel, a mobile device, or received from a remote location (such as from a service center).

[0017] According to an embodiment, in response to said maintenance request, the controller bypasses, for example in its software, the part of the elevator safety chain comprising the electrical safety device. In this way, only said safety chain part can be bypassed and thus said bypass does not affect the operation of the rest of the safety chain. This means that it is possible to manually drive the car using a manual operating panel under the control of the safety chain (still a functional part of the safety chain).

[0018] Thus, the safety chain (with the bypass) allows the car to be manually driven by a maintenance technician standing on the car roof to a position where the maintenance technician can access the electrical safety device from the elevator car roof, i.e., provides the maintenance technician with safe and easy access to the electrical safety device to independently repair the electrical safety device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be described in more detail below by means of preferred embodiments with reference to the accompanying drawings, in which:

[0020] Figure 1 shows an elevator,

[0021] Figure 2 A block diagram showing some elements of an elevator,

[0022] Figure 3 A prior art example of repairing an elevator limit switch is shown, and

[0023] Figure 4 An example of providing access to an electrical safety device is shown. DETAILED DESCRIPTION

[0024] Figure 1 Some aspects of an exemplary elevator 100 are schematically shown, the elevator 100 comprising an elevator car 10 and an electric drive 4 operable to drive the car 10 in an elevator shaft 1 to transfer passengers and / or freight between landings 30 . Figure 1 The electric drive 4 in the embodiment of the present invention comprises an elevator hoisting machine 5 and an elevator drive unit. The hoisting machine 5 comprises an elevator hoisting motor 51 (such as a permanent magnet motor) for driving the car 10 and a hoisting machine brake 52, which is configured to be applied to a traction sheave 53 or a rotation axis of the hoisting machine to stop the movement of the car or keep the car stationary at a landing 30 in the shaft 1.

[0025] Figure 1 The elevator in has hoisting ropes 6 supporting a car 10 , which run via a traction sheave 53 and are connected to a counterweight 7 .

[0026] Figure 1 and Figure 2 The elevator 100 in the embodiment includes an elevator controller 110, which is configured to control the elevator operation in a normal operation mode and a manual operation mode. The elevator 100 includes an electric drive 4 for operating an elevator car 10, and a manual operation panel 2 arranged inside the elevator shaft for manually driving the elevator car. The manual operation panel can be arranged, for example, in the elevator shaft pit 1b or on the car roof 10a of the elevator car.

[0027] The elevator 100 comprises a safety chain 50, and the safety chain 50 comprises a plurality of safety devices 20; 21 for controlling the safety of the elevator.

[0028] The safety chain 50 comprises electrical safety devices 20; 21, such as limit switches, which are configured to provide information about the elevator car 10 approaching the temporary refuge space 1a; 1b in the shaft 1. Figure 3 and Figure 4 As shown, a temporary refuge space 1a; 1b can be established near the end of the shaft. According to an embodiment, instead of a mechanical switch, the electrical safety device can be, for example, a camera or a contactless proximity switch.

[0029] The safety chain 50 further comprises a controller 110 configured to obtain information from the electrical safety device and to generate a stop command 4 . 1 to stop the movement of the car 10 before entering the refuge space 1 a ; 1 b .

[0030] In response to the maintenance request 3 of the electrical safety device 20 ; 21 , the controller 110 excludes the electrical safety device 20 ; 21 from operation of the safety chain 50 by bypassing the portion of the safety chain 50 including the electrical safety device in software to allow manual driving of the car using the manual operating panel 2 .

[0031] The car 10 is provided with a car door 11 and a car floor 12. The car door 11 includes a door that can move between a closed position and an open position. The car door 11 can remain locked when the car 10 moves, unlock when the car 10 enters a landing area located at and near the landing 30, and open when the car 10 stops at the landing 30. The car door 11 can be closed before the car 10 leaves the landing 30, and locked when the car 10 leaves the landing area. The car 10 is provided with a door operator 13, which is connected to the car door 11 and is used to temporarily connect the car door 11 to a landing door 31 provided at each landing 30 when the car 10 resides in the landing area of ​​the landing 30, so that the landing door 31 moves between a closed position and an open position together with the car door 11, thereby allowing passengers to move between the landing 30 and the car 10 when the car 10 is at the landing 30, and preventing passengers from entering the shaft 1 when the elevator car 10 is not at the landing 30.

[0032] Figure 2 An exemplary block diagram of some elements of elevator 100 is shown.

[0033] According to one embodiment, the elevator 100 comprises means for determining an operating condition of the electrical safety device 20; and means for generating a signal indicating an abnormality in the operation of the electrical safety device.

[0034] According to one embodiment, the controller 100 is configured to bypass the portion of the safety chain 50 including the electrical safety devices 20; 21 to allow the car 10 to be manually driven to a position where a service technician can access the electrical safety devices from the elevator car roof 10a.

[0035] According to one embodiment, the elevator 100 further comprises a mechanical safety device configured to protect a temporary refuge space 1a; 1b in the elevator shaft 1. According to one embodiment, the mechanical safety device comprises a buffer in the temporary refuge space and / or a railing on the car roof 10a.

[0036] According to one embodiment, the controller 110 is configured to bypass the portion of the safety chain 50 including the electrical safety device 20; 21 to allow manual driving of the car under the control of the rest of the elevator safety chain. According to an embodiment, the controller 110 is an electronic safety controller configured to run safety software. According to an embodiment, the controller 110 is configured to generate a stop command 4.1 for the lifting machinery brake 52.

[0037] According to one embodiment, the electrical safety device is a limit switch 20; 21 configured to open and interrupt the safety chain 50 when the car 10 reaches the limit switch in the manual drive operation mode. According to one embodiment, the electrical safety device is a camera or a non-contact proximity switch.

[0038] According to one embodiment, the electrical safety device is configured to set a limit to the movement of the car towards a temporary refuge space 1a; 1b, preferably established near the end of the shaft.

[0039] Figure 3 A prior art example of repairing a faulty limit switch of an elevator is shown.

[0040] In phase I, the top check limit switch 21 has an incorrect polarity, in other words, there is a malfunction of the electrical safety device 21. The elevator car 10 passes the limit switch 21 during normal operating mode and due to the wrong polarity, a malfunction of said limit switch 21 is detected, since it does not function during cooperation with its counterpart 22 in the car 10 at the top landing 30.

[0041] In Phase II, a maintenance technician arrives on site to perform maintenance on the elevator. They enter shaft 1 and attempt to perform a top car inspection, but are prevented from doing so due to a faulty limit switch 21. They are unable to resolve the limit switch problem because car 10 blocks access.

[0042] In Phase III, one maintenance technician leaves the shaft 1 to the manual operating panel or machine room to lower the elevator to a better position in rescue drive mode in order to resolve the problem with the faulty limit switch 21. Another maintenance technician stays on the car roof 10a during the manual lowering of the car. The bypass jumper in the maintenance user interface needs to be used to bypass the fault input. The use of the bypass input also bypasses other safety devices and contacts. In order to approach the faulty limit switch 21, the car 10 needs to be stopped to a position where maintenance work can be performed. Because this is usually not at the level of the landing 30, multiple attempts may be required. If the car does not stop to a feasible position, this operation needs to be repeated. The position where the maintenance technician can approach the car roof 10a is not necessarily the best position for resolving the problem with the faulty limit switch 21, so a ladder or similar assistance is required.

[0043] Figure 4 An example of providing access to an electrical safety device 21 is shown. The example shows how a faulty electrical safety device 21 can be safely repaired by a single service technician.

[0044] In phase A, the top check limit switch 21 has an incorrect polarity, in other words, the electrical safety device 21 fails. A maintenance technician drives the car 10 to the lower landing 30 closest to the fault check limit switch 21. The door at the lower landing 30 remains open. The maintenance technician secures the area and manually drives the elevator car using the manual operation panel 2 provided on the car roof 10a inside the elevator shaft.

[0045] In phase B, the maintenance technician manually drives the car upward to a position where the maintenance technician can access the fault limit switch 21 from the car roof 10a.

[0046] In phase C, once the faulty limit switch 21 has been repaired and the operation of the corresponding limit switch 20 has been verified, the maintenance technician runs the elevator down to the level of the landing 30. The maintenance technician deactivates the input device, such as a button and / or a switch, on the manual operating panel 2 to end the manual drive operating mode and leaves the shaft 1.

[0047] The method for providing access to the electrical safety device 20; 21 comprises obtaining, by the controller 110, information provided by the electrical safety device about the elevator car 10 approaching the temporary refuge space 1a; 1b. In addition, the method comprises generating, by the controller, a stop command 4.1 to stop the movement of the elevator car before entering the refuge space; and in response to a maintenance request 3 for the electrical safety device, excluding, by the controller, the electrical safety device from the operation of the elevator safety chain 50 to allow manual driving of the elevator car using the manual operating panel 2; and driving the elevator car 10 by means of the manual operating panel 2 to a position where the electrical safety device is accessible from the elevator car roof.

[0048] The use of the present invention is not limited to the embodiments disclosed in the accompanying drawings. It is obvious to those skilled in the art that, with the advancement of technology, the inventive concept can be implemented in various ways. The present invention and its embodiments are not limited to the above examples, but can be varied within the scope of the claims.

Claims

1. An elevator (100), comprising: An elevator car (10) within an elevator shaft (1) adapted to transfer passengers and / or freight between landings (30); an electric drive (4) for operating the elevator car; A manual operation panel (2), the manual operation panel (2) being arranged inside the elevator shaft and used for manually driving the elevator car; An elevator safety chain (50), the elevator safety chain (50) comprising a controller (110) connected to a plurality of safety devices for monitoring elevator safety; wherein the safety chain comprises an electrical safety device (20, 21) configured to provide information about the elevator car approaching a temporary refuge space (1a, 1b) in the shaft; and wherein the controller (110) is configured to obtain information from the electrical safety device and generate a stop command (4.1) to stop the movement of the elevator car before entering the refuge space; Features: The controller (110) is configured to: In response to a maintenance request for the electrical safety device (20, 21), the electrical safety device (20, 21) is excluded from the operation of the elevator safety chain (50) so that the elevator car can be manually driven using the manual operation panel (2).

2. The elevator according to claim 1, wherein: The elevator comprises means for determining an operating condition of the electrical safety device (20; 21) and means for generating a signal indicating an abnormality in the operation of the electrical safety device.

3. An elevator according to claim 1 or 2, wherein the controller (110) is configured to bypass the portion of the elevator safety chain (50) including the electrical safety device (20, 21) to allow the car (10) to be manually driven to a position where a maintenance technician can access the electrical safety device from the elevator car roof (10a).

4. An elevator according to any one of the preceding claims, wherein: The elevator further comprises a mechanical safety device, which is configured to protect the temporary refuge space (1a, 1b) in the elevator shaft (1).

5. An elevator according to any one of the preceding claims, wherein: The controller (110) is configured to bypass the portion of the elevator safety chain (50) including the electrical safety devices (20, 21) to allow manual driving of the car under control of the remainder of the elevator safety chain.

6. An elevator according to any one of the preceding claims, wherein: The controller (110) is an electronic security controller configured to run security software.

7. An elevator according to any one of the preceding claims, wherein: The electrical safety devices (20, 21) are limit switches.

8. The elevator according to claim 7, wherein: The limit switch (20; 21) is configured to open and interrupt the elevator safety chain (50) when the car (10) reaches the limit switch in a manual drive operation mode.

9. The elevator according to claim 1, wherein: The electrical safety device is a camera or a contactless proximity switch.

10. An elevator according to any one of the preceding claims, wherein The electrical safety device (20; 21) is configured to set a limit on the movement of the car toward the temporary refuge space (1a; 1b).

11. An elevator according to any one of the preceding claims, wherein: The temporary refuge space (1a, 1b) is established near the end of the shaft.

12. An elevator according to any one of the preceding claims, wherein: The electric drive (4) comprises an elevator hoisting machine (5) and an elevator drive unit.

13. The elevator according to claim 12, wherein: The controller (110) is configured to generate a stop command (4.1) to a brake (52) of a lifting machine (5).

14. The elevator according to claim 12 or 13, wherein: The elevator hoisting machine (5) comprises an elevator hoisting motor (51), for example a permanent magnet motor, and a traction sheave (53) for the hoisting ropes (6) of the car and the elevator counterweight (7).

15. A method for providing access to an electrical safety device (20, 21) of an elevator (100) according to any one of the preceding claims, comprising: The controller (110) obtains information provided by the electrical safety device regarding the elevator car (10) approaching a temporary refuge space (1a; 1b) in the shaft (1); as well as generating a stop command (4.1) by the controller to stop the movement of the elevator car before entering the refuge space; as well as In response to a maintenance request (3) for the electrical safety device (20, 21), the controller (110) excludes the electrical safety device from operation of the elevator safety chain (50) to allow manual driving of the elevator car using the manual operation panel (2); as well as The elevator car is driven by means of the manual operating panel (2) to a position where the electrical safety device can be accessed from the elevator car roof.

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