Method and elevator system for rescue operation

Abstract

The invention relates to an elevator system comprising at least a first elevator (3) having a first elevator car (8), a first counterweight (4) and a first drive system (5), and a second elevator (13) having a second elevator car (18), a second counterweight (14) and a second drive system (16). For a simple and quick rescue operation, the elevator system comprises a regenerative operation interface (22) in the first elevator (3) for providing electric power from the first elevator (3) to the second elevator (13), and a regenerative operation interface (22) in the second elevator (13) for receiving electric power from the first elevator (3) and for energizing the second drive system (16) for driving the second elevator car (18) to a rescue position.

Description

Technical Field

[0001] The present invention relates to a solution for facilitating rescue operations in elevator systems, for example, during power outages in power grids. Background Technology

[0002] Sometimes, operational abnormalities (such as power outages) can disrupt elevator operation, causing the elevator car to stop between floors. In such cases, the elevator car needs to be repositioned to a rescue floor to release passengers. This operation is known as a rescue operation.

[0003] Traditionally, on-site technicians would travel to the elevator site and use a manual lever to disengage the lifting machinery brakes, allowing the elevator car to drift to the rescue floor by gravity. This solution, of course, only works with unbalanced loads, where gravity can be used to move the elevator car in the desired direction.

[0004] However, if the load is unbalanced or unbalanced in the wrong direction to prevent the elevator car from moving to the rescue position by gravity, a separate, manually operated hoist is required. In this case, the position of the elevator car can be changed using this hoist. Such a rescue operation is slow and laborious. Summary of the Invention

[0005] If the obtained load information indicates a balanced state of the second elevator car or an unbalanced state in the direction preventing the second elevator car from drifting toward the rescue position, then by initiating a regenerative operation using the first elevator, the drive system of the second elevator, which has a second elevator car requiring rescue operation, can be energized using power from the first elevator. The term "drift" in this document refers to the uncontrolled movement of the second elevator car by gravity when the brake is open, i.e., without power being supplied to the drive system of the second elevator car from an external power source. With this solution, the power required to drive the second elevator car to the rescue position can be generated without the need for expensive additional equipment. Attached Figure Description

[0006] In the following description, the invention will be described in more detail by way of example and with reference to the accompanying drawings, wherein,

[0007] Figure 1 It is a flowchart illustrating the method, and

[0008] Figure 2 It shows that it can be implemented Figure 1 Elevator systems using this method. Detailed Implementation

[0009] Figure 1 It is a flowchart illustrating the method, and Figure 2 This indicates that it can be implemented. Figure 1Elevator system 1.

[0010] Elevator system 1 includes a first elevator 3 having a first elevator car 8, a first counterweight 4, and a first drive system 5. The first drive system 5 includes a first hoist 6 having a motor and a brake 23, and a first control cabinet 7 having a motor drive (e.g., a frequency converter). The first drive system 5 moves the first elevator car 8 and the first counterweight 4 in a first elevator shaft 10 via a rope 11 between the building's floors 9. In the illustrated example, as an example, it is assumed that the first elevator also has a compensating rope 12 between the elevator car 8 and the counterweight 4.

[0011] In addition, elevator system 1 includes at least one additional elevator. Figure 2 In the second elevator 13, therein, there is a second elevator car 18, a second counterweight 14, and a second drive system 15. The second drive system 15 includes a second hoist 16 having a motor and a brake 23, and a second control cabinet 17 having a motor driver (e.g., a frequency converter). The second drive system 15 moves the second elevator car 18 and the second counterweight 14 in the second elevator shaft 20 via ropes 11 and by compensating ropes 12 utilizing the building's floors 9.

[0012] In the illustrated example, as an example, it is assumed that the first control cabinet 7 and the second control cabinet 17 are implemented as separate control cabinets spaced a distance from each other. In some embodiments, the first and second control cabinets may be placed side by side, as shown, or alternatively integrated into a single control cabinet. In this case, the single control cabinet includes the necessary components for the first elevator 3 and the second elevator 13.

[0013] If one of the first and second elevator cars becomes stuck between floors 9 of the building due to a power outage in the main power grid supplying power to the building, a rescue operation is performed to move the stuck elevator car to a floor where passengers can exit the second elevator car, such as... Figure 1 The implementation is shown below. As an example, in the following text, assume that the second elevator car is stuck and requires rescue operation.

[0014] In step A, the load information of the second elevator car 18 is obtained. If such a load sensor is provided, this load information can be obtained from load sensor 2. In the illustrated example, as an example, it is assumed that both the first elevator car 8 and the second elevator car 18 are equipped with load sensors at the interface where the elevator cars in question are suspended from the rope 11. In this way, the load of the elevator car, i.e., the weight of the elevator car carrying passengers and goods, can be determined based on the indication from load sensor 2 of the second elevator car 18. This reading, combined with prior information about the load, is used to determine the load information, which is about what the load should be when the second elevator car is in a balanced state.

[0015] An alternative method to obtain load information for the second elevator car 18 is to briefly open the brake of the second elevator car 18 and monitor any movement and direction of movement of the second elevator car 18 while the brake is open. For example, the opened brake may include the lifting mechanical brake 23 of the second drive system 16. This monitoring of brake opening and movement can be performed manually by field service personnel. Using this alternative method, a load sensor is not required to obtain load information.

[0016] If an imbalance in the correct direction is determined in step B—in other words, the second elevator car 18 drifts towards the rescue position by gravity when brake 23 is released—then in step C, by releasing the brakes in the second elevator and allowing the second elevator car 18 to drift to the rescue position by gravity while applying motor braking to maintain a suitable speed, it is sufficient to initiate the drift of the second elevator car 18 to the rescue position. Depending on the implementation, drifting may require the release of other brakes besides the lifting mechanical brake. For example, motor braking can be influenced by actively modulating the motor inverter transistors to generate a rotating magnetic field. Alternatively, motor braking may be affected by a passive short circuit in the motor windings of the permanent magnet elevator motor to achieve passive dynamic braking. In either case, no electricity is required to drive the second elevator car 18 to the rescue position. In this case, a suitable rescue position is the nearest floor 9 below the position where the second elevator car 18 is stuck in the second elevator shaft 14, where passengers and goods can be removed from the second elevator car 18.

[0017] However, if a state of balance or an imbalance in the wrong direction is detected in step B, additional measures are required for the rescue operation. If balance is determined, it means that the second elevator car 18 and the counterweight 14, as well as the ropes 11 and compensating ropes 12, are in equilibrium, and therefore the second elevator car 18 remains stationary in the elevator shaft 14 when the brake 23 is released. On the other hand, if an imbalance in the wrong direction is determined, it means that the imbalance is in the direction preventing the second elevator car from drifting towards the rescue position. This could occur if the second elevator car 18 is heavily loaded and located below the lowest floor 9, causing, for example, a downward drift due to gravity in the wrong direction.

[0018] Therefore, if it is determined in step B that the second elevator car 18 is in a balanced state or in an unbalanced state in the wrong direction, then in step D, a regeneration operation is initiated in the first elevator 3 to provide power to the second drive system 15 of the second elevator 13.

[0019] In step E, the second drive system 15 of the second elevator 13 is powered by the power supplied from the first elevator 3 to drive the second elevator car 18 to the rescue position.

[0020] To supply power from the first elevator 3 to the second elevator 13, the building's power distribution system will be utilized. According to an exemplary embodiment, the building's power distribution network can be utilized. Alternatively, a power supply conductor 21 (e.g., a cable) can be used, which can connect between the regeneration operation interfaces 22 in the first elevator 3 and the second elevator 13, for example, between the first and second control cabinets 7 and 17. This power supply conductor can, for example, be permanently attached between these interfaces, in which case a maintenance technician can use it by turning one or more switches in the elevator system's rescue operation control. Alternatively, the power supply conductor 21 can be a separate cable, which is installed and connected in a separate method step before initiating the regeneration operation of the first elevator 3. Using the power supply conductor 21, the drive systems of the first and second elevators can be connected to provide a common power distribution network for the elevator systems, thereby enabling power sharing between the elevators. Alternatively, the DC links of the power converters of the drive systems can be interconnected via one or more power cables or busbars.

[0021] Depending on the balance within the first elevator during the moment when it is allowed to rise or fall in the first elevator shaft 10 by gravity, a regenerative operation can be implemented to utilize the potential energy of the first elevator car 8, or alternatively, the potential energy of the first counterweight 4. In this case, the regenerative operation of the first lifting mechanism 6 of the first elevator can be used to generate electricity.

[0022] In some implementations, the power consumption of the second elevator 13 is monitored during power-on. This monitoring can be performed by the motor driver in the second control cabinet 17, from which information about power consumption is transmitted to the first control cabinet 7. The first control cabinet 7 uses the received information to control the power supplied to the second elevator 13 to match the power consumption of the second elevator 13 during power-on. This matching can be achieved by using a resistor (e.g., the braking resistor of the first elevator) or the motor of the first hoist 6 to dissipate the additional regenerative power as heat in the drive system of the first elevator 3. This proactive control of regenerative power eliminates the risk of UPS (uninterruptible power supply) failure due to the supplied regenerative power, which is supplied to the elevator system or each individual elevator in the elevator system.

[0023] The advantage of the solution described above is that during rescue operations required due to a power failure in the main power grid, it is not necessary to provide a backup power source, such as a UPS, for elevator system 1, which has sufficient power to drive the elevator car. Elevator system 1 can instead be equipped with, for example, a much smaller backup battery, which provides sufficient power only for emergency lighting, brake control operations, and control circuitry; however, it is not necessary to draw power from the backup battery to drive the hoisting machinery to move the elevator to the rescue position. This small and relatively inexpensive backup battery can be provided individually for each elevator in the elevator system, or it can serve as a single common backup battery for all elevators in the same system.

[0024] In the preceding explanation, for simplicity, it has been stated that the first elevator is used for regeneration operations, while the second elevator car is driven to the rescue position. However, in practice, the roles can be reversed, such that the first elevator car is driven to the rescue position during the regeneration operation of the second elevator.

[0025] It should be understood that the above description and accompanying drawings are for illustrative purposes only. It will be apparent to those skilled in the art that changes and modifications can be made to the invention without departing from its scope.

Claims

1. A method for performing a rescue operation in an elevator system to move a stuck elevator car to a rescue position at a floor, the elevator system having at least a first elevator (3) with a first elevator car (8), a first counterweight (4) and a first drive system (5), and a second elevator (13) with a second elevator car (18), a second counterweight (14) and a second drive system (15), characterized in that, The rescue operation for the stuck second elevator car includes: By opening the brake (23) of the second elevator (13), monitoring the movement of the second elevator car (18), and determining the load information of the second elevator car (18) based on the detected movement and direction of the second elevator car when the brake (23) is opened, the load information of the second elevator car (18) is obtained (A). If the obtained load information indicates an imbalance in the second elevator car (18) or an imbalance in the direction preventing the second elevator car from drifting toward the rescue position, then the first elevator (3) is used to initiate (D) regeneration operation to supply power from the first elevator (3) to the second drive system (15), and Power is supplied from the first elevator (3) to power the second drive system (17) to drive the second elevator car (18) to the rescue position at the floor.

2. The method according to claim 1, comprising: Prior to the start-up, the building’s power distribution system, which supplies power from the first elevator (3) to the second drive system (15), is connected between the first elevator (3) and the second elevator (13).

3. The method according to claim 1 or 2, comprising: If the obtained load information indicates an imbalance in the second elevator car (18) in the direction that allows the second elevator car (18) to drift to the rescue position, then the second elevator car (18) is initiated to drift to the rescue position.

4. The method according to any one of claims 1 to 3, comprising: During the power-on period, the power consumption of the second elevator (13) was monitored, and During the power-on period, the power supplied to the second elevator (13) is controlled to match the power consumption of the second elevator.

5. The method according to claim 4, comprising: The excess regenerative power generated by the resistor of the first elevator (3) is used to control the power supplied to the second elevator (13) during the power-on period to match the power consumption of the second elevator (13).

6. The method of claim 4, comprising: The first hoist (6) of the first elevator (3) uses excess regenerative power to generate heat to control the power supplied to the second elevator (13) during the power-on period to match the power consumption of the second elevator (13).

7. An elevator system, comprising: At least a first elevator (3) and a second elevator (13), the first elevator (3) having a first elevator car (8), a first counterweight (4) and a first drive system (5), and the second elevator (13) having a second elevator car (18), a second counterweight (14) and a second drive system (15). The regenerative operation interface (22) in the first elevator (3) is used to supply power from the first elevator (3) to the second elevator (13), and The regeneration operation interface (22) in the second elevator (13). The elevator system is characterized by the following features: For the rescue operation of moving the stuck elevator car to a rescue position at a floor level, the elevator system includes: The power supply conductor (21), which is a separate cable, is connected in a separate step between the regeneration operation interfaces (22) in the first elevator (3) and the second elevator (13) before initiating the regeneration operation, so that if the balance of the second elevator car (18) is determined or if there is an imbalance in the wrong direction, power is supplied from the first elevator (3) to the second elevator (13) during the rescue operation to energize the second drive system (15) to drive the second elevator car (18) to the rescue position at the landing floor, or One or more switches in the rescue operation control of the elevator system, and a power supply conductor (21) permanently attached to the regeneration operation interface (22), which is used by a service technician who turns the switches to provide power from the first elevator (3) to the second elevator (13) in regeneration operation to activate the second drive system (15) to drive the second elevator car (18) to the rescue position at the landing floor in the event of a determination of the balance of the second elevator car (18) or an imbalance in the wrong direction during the rescue operation.

8. The elevator system according to claim 7, wherein, The elevator system includes at least one control cabinet (7, 17) which monitors the power consumption of the second elevator (13) while the second drive system (15) drives the second elevator car to the rescue position, and adjusts the power supplied by the regeneration operation from the first elevator (3) through the building's power distribution system to match the power consumed by the second elevator (13) during operation.

9. The elevator system as described in claim 7 or 8, characterized in that, The power is supplied from the first elevator (3) to the second elevator (13) via the building's power distribution system.

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