Method for early detection of landing door switch in multi-car parallel elevator system

Abstract

The application provides a method for early detection of landing door switch of multi-car parallel elevator system. Each landing door is provided with a landing door switch for reflecting opening or closing of the landing door. Each landing door switch is connected to a safety circuit. All landing door switches belong to more than one safety circuit. At least one connecting device for connecting to the safety circuit is arranged on the car. The connecting device for connecting to the safety circuit on one car is not fixed in position on the car. When the landing door switch is closed, the safety circuit is connected. When the landing door switch is opened, the safety circuit is disconnected. When the safety circuit connected by the connecting device is connected, the control system controls the car where the connecting device is located to normally operate. When the safety circuit connected by the connecting device is disconnected, the control system controls the car where the connecting device is located to stop. The application improves the operation efficiency of the car and can detect the state of the landing door switch in front of the car to respond in advance.

Description

Technical Field

[0001] This invention belongs to the field of elevator technology, specifically a method for early detection of landing door opening and closing in a multi-car parallel elevator system. Background Technology

[0002] In modern society and economic activities, elevators have become an indispensable vertical transportation tool for carrying people and goods. Since the invention of the elevator in 1854, elevator cars have always operated using a wire rope traction drive system. This involves a machine room, traction motor, and reduction gear located on the top floor of the building, which drives the wire rope to pull the car and counterweight along tracks within the shaft. This drive method typically allows only one car to operate within a single shaft. While single-car elevators can meet the needs of low-rise buildings and floors with low passenger traffic, with the rapid development of modern cities and the rise of high-rise and super high-rise buildings, the drawbacks of single-car elevators—long waiting times and low transport efficiency—have become increasingly apparent. This traditional single-car elevator operating mode is no longer suitable for the rapidly evolving needs of modern urban architecture.

[0003] To improve building space utilization and elevator efficiency, and reduce building and elevator costs, a multi-car parallel elevator is being developed and applied as engineering technology continues to advance. This multi-car parallel elevator utilizes direct drive technology without traction steel wire ropes, enabling multiple elevator cars to operate simultaneously within the same shaft. Elevators in different shafts can switch shafts for operation, achieving overtaking maneuvers.

[0004] In traditional traction machine elevators, each shaft corresponds to a single car and associated landing doors. To ensure the safety of the elevator system and prevent falls and shearing injuries caused by abnormal opening of the landing doors, each landing door is equipped with a landing door lock electrical interlock switch. All landing door lock electrical interlock switches for a single shaft are connected in series to form a safety circuit. The elevator can only operate normally when all landing door lock electrical interlock switches are closed; if at least one landing door lock electrical interlock switch is not closed, the safety circuit is open, and the elevator cannot operate.

[0005] However, in a multi-car intelligent parallel elevator system, there may be multiple cars running simultaneously on the same track. If the traditional elevator safety circuit's method of locking the landing doors is still used, then when a car opens its door normally at a landing in the shaft, the safety circuit of the entire shaft will be cut off, forcing all cars on that track to stop running. This will obviously greatly reduce the operating efficiency of the elevator system. Summary of the Invention

[0006] To address the aforementioned problems in existing technologies, the purpose of this invention is to provide a method for early detection of landing door opening and closing in a multi-car parallel elevator system. The car's operating state is only related to its currently connected safety circuit and is unrelated to the states of other safety circuits. This does not affect the operating state of cars connected to other safety circuits, thus improving car operating efficiency. The position of the connecting device on the car for accessing the safety circuit relative to the car is adjustable, not fixed. This allows for early detection of the landing door opening and closing status ahead of the car, enabling a timely response.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A method for early detection of landing door opening and closing in a multi-car parallel elevator system, the elevator system comprising at least two vertical tracks, at least one switching device, and at least two self-driven cars that can smoothly switch between the two tracks via the switching device, the elevator system including a control system, each landing door having a landing door switch for responding to the opening or closing of the landing door, each landing door switch being connected to a safety circuit, all landing door switches belonging to more than one safety circuit, the car having at least one connection device for connecting to the safety circuit, the position of the connection device on the car being not fixed, when the landing door switch is closed, the safety circuit is connected, when the landing door switch is open, the safety circuit is disconnected, when the safety circuit connected to the connection device is connected, the control system controls the car where the connection device is located to operate normally, when the safety circuit connected to the connection device is disconnected, the control system controls the car where the connection device is located to stop.

[0009] As a further improvement to the above technical solution:

[0010] When the safety circuit connected to the connecting device is disconnected, the control system controls the car containing the connecting device to stop. After the car stops, the car can switch from being connected to one safety circuit to being connected to another safety circuit.

[0011] The connection device for accessing the safety circuit on a car is located at the front of the car or at the front end of the car along the current direction of car travel.

[0012] The car is equipped with a connecting device that is movably mounted on the car.

[0013] Each car is equipped with at least two connecting devices connected in series, and all connecting devices on each car are configured such that only one connecting device can be connected to the safety circuit at a time.

[0014] Each car is equipped with at least two switches, and each connecting device is connected in series with a switch. The connecting device and the switch connected in series with it are connected to or disconnected from the safety circuit as a whole. When the switch is closed, the connecting device is connected to the safety circuit. When the switch is open, the connecting device cannot be connected to the safety circuit.

[0015] The control system controls the switches to close or open. In the current direction of travel of the car, the switch connected in series with one of the connecting devices located at the front or foremost end of the car is closed, while the switches connected in series with the other connecting devices on the car are opened.

[0016] Each safety circuit has at least one floor door switch. When a safety circuit has at least two floor door switches, the floor door switches are connected in series in the safety circuit.

[0017] The connecting device is a current collector.

[0018] When the safety circuit of the landing door switch corresponding to a certain hall door on a certain floor is disconnected, the connecting device on the car moving towards that hall door is connected to the safety circuit of the landing door switch corresponding to that hall door and is stopped. The car stops above or below the floor corresponding to that hall door and cannot enter that floor.

[0019] The beneficial effects of this invention are:

[0020] 1) The landing door switches are detected in sections or in zones, and multiple independent safety circuits are provided. The car's operating status is only related to the safety circuit it is currently connected to, and is not related to the status of other safety circuits. This does not affect the operating status of the car connected to other safety circuits, thus improving the car's operating efficiency.

[0021] 2) The position of the safety circuit in the hoistway is fixed, but the position of the connecting device on the car for accessing the safety circuit is adjustable relative to the car, not fixed. This allows for advance detection of the opening and closing status of the landing doors ahead of the car, enabling an early response and making the car's operating status adjustable. When there are at least two connecting devices, if one connecting device fails or the safety circuit connected to one connecting device is disconnected, causing the car to stop, but this disconnection is due to a landing door opening failure, the car can actively escape by relying on the connecting device in another position to connect to other normally connected safety circuits.

[0022] 3) When the utilization rate of the car in the entire system is very low, the idle cars can be arranged in a concentrated location as much as possible through the control of the safety circuit. Attached Figure Description

[0023] Figure 1 This is a schematic diagram illustrating that the distance between two adjacent cars is greater than the safety distance in one embodiment of the present invention.

[0024] Figure 2 This is a schematic diagram of the safety circuit where the lower car stops at the landing level and the upper car enters the landing level for stopping, according to one embodiment of the present invention. Detailed Implementation

[0025] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0026] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0027] Methods for early detection of landing door opening and closing in multi-car parallel elevator systems, such as... Figure 1 and 2 As shown, the elevator system includes at least two vertical tracks, at least one switching device, and at least two self-driven cars that can be smoothly switched between the two tracks via the switching device.

[0028] Each hall door, or landing door, is equipped with a landing door switch. When a hall door is closed, its corresponding landing door switch is closed; when a hall door is normally or abnormally opened, its corresponding landing door switch is open. The landing door switch is connected to a safety circuit. When the landing door switch is closed, the safety circuit is connected; when the landing door switch is open, the safety circuit is disconnected. Each hall door's landing door switch corresponds to one safety circuit, or the landing door switches of at least two adjacent hall doors can be connected in series and then connected to a safety circuit, meaning multiple hall doors connected in series to a single safety circuit share one safety circuit. As can be seen, the elevator system has multiple safety circuits, each independent of the others. That is, the elevator system's safety circuits are zoned or segmented. For detailed information, please refer to the applicant's patent applications 202111337196X and 2020112707004.

[0029] At least one connecting device is installed on the car, which is used to connect to a safety circuit. When the safety circuit connected to the connecting device of a car is open, it means that the landing door switch of the connected safety circuit is closed and the corresponding hall door is closed. At this time, the passengers in the car passing through it will not be at risk of falling or being cut off, and the control system controls the car to operate normally and pass through the hall door. When the safety circuit connected to the connecting device of a car is closed, it means that the landing door switch of the connected safety circuit is open and the corresponding hall door is open. At this time, the passengers in the car passing through it will be at risk of falling or being cut off, and the control system controls the car to stop and prevents it from running.

[0030] Preferably, the connecting device is a current collector.

[0031] Based on the above structure, the elevator system has multiple safety circuits. As the car travels along the tracks, the connecting devices on the car sequentially connect to different safety circuits corresponding to the door switches on each floor. If the connected safety circuit is closed, the car can operate normally; if the connected safety circuit is open, the control system stops the car. In other words, the car's operating state depends only on the state of its connected safety circuits and is independent of other safety circuits in the elevator system.

[0032] The above-mentioned detection method is segmented detection or zoned detection. Opening a landing door on the same shaft that is far from the car will not affect the operation of that car. That is, in a multi-car parallel elevator system, a segmented detection method for landing door opening and closing can be used. This way, even if a car levels normally in another location, it will not affect the normal operation of other cars located further away. However, the overall height of the car is usually higher than the floor height. When the connection devices installed in each car are in relatively consistent positions, the above method requires at least two consecutive floors' landing door switches to be connected in series at locations other than the shaft ends to be effective. This prevents the most efficient use of the operational clearance between cars, affecting the operating efficiency of the multi-car parallel elevator system.

[0033] To accurately detect the current operating environment of the car, only one safety circuit can be connected to a car at a time. To ensure safe operation and improve car operating efficiency, it is necessary to detect the status of the safety circuit that the car is about to reach in advance. This is to ensure the safety of car operation and stopping. If another car (the car in front) is stopped in front of the car behind, and the safety circuit connected to the car behind is connected, the car behind will continue to operate normally, which may result in the car behind colliding with the car in front. Therefore, the car behind must detect the status of the car in front in advance and react accordingly.

[0034] To detect the safety circuit status of the landing door the car will reach in advance and to ensure that only one safety circuit is connected to a car at a time, this solution uses a variable-position connection device on the car. This variable-position connection device can be implemented in several ways: Solution 1: The connection device is movably installed on the car. Specifically, it can be mounted on a robotic arm, which can be controlled to move, extending upwards when the car is moving upwards and downwards when the car is moving downwards. Solution 2: At least two connection devices are installed on the car, located at different positions within the car. These devices are connected in parallel, with only one device connected to the safety circuit at a time.

[0035] As can be seen from the above, each car is provided with one or more connecting devices, but only one connecting device is connected to the safety circuit at a time. The location of the connecting device on a car that connects to the safety circuit is either in front of the car or at the front end of the car along the current direction of car travel.

[0036] When there is only one connecting device on the car, the control system controls the connecting device to move to the front end of the car or in front of the car in its running direction. Specifically, the controller controls the movement of the robotic arm connected to the connecting device, so that the robotic arm drives the connecting device to move.

[0037] When multiple connecting devices are installed on each car, only one of these devices can be connected to the safety circuit at a time. Specifically, each car has multiple switches, and each connecting device is connected in series with a switch. The connecting device and the switch connected in series with it are connected to or disconnected from the safety circuit as a whole. When the switch is closed, the connecting device is connected to the safety circuit; when the switch is open, the connecting device is disconnected from the safety circuit, meaning the connecting device cannot be connected to the safety circuit at this time. The opening and closing of the switch can be controlled by a PLC or other controller. In the current direction of travel of the car, the connecting device located at the frontmost or foremost point of the car is in a state where it can be connected to the safety circuit, meaning the switch connected in series with this connecting device is in a closed state, and the other switches are in an open state.

[0038] Preferably, each car is equipped with two connecting devices, which are connected in series and spaced apart along the length of the track. The position of the connecting device at the connection point with a safety circuit meets the following requirements: when the safety circuit of the landing door switch corresponding to a landing door on a certain floor is disconnected, when the connecting device on the car running towards that landing door is stopped in the safety circuit of the landing door switch corresponding to that landing door, the car stops above or below the floor corresponding to that landing door and cannot enter that floor, so as to avoid collision between the car and the car parked at the landing door. In addition, after the car stops, the connecting device on the car can also be connected to other safety circuits: for a car with only one connecting device, the connecting device can be moved by controlling the robotic arm so that the connecting device can be connected to other safety circuits; for a car with two connecting devices, the positions of the two connecting devices allow them to be connected to different safety circuits respectively, preferably to two adjacent safety circuits.

[0039] To meet the above requirements, the connection device can be inserted into the safety circuit of the corresponding landing door switch by reasonably setting the position. Specifically, the connection device on the car can extend out of the car, that is, along the car's running direction, the connection device is located at the front end of the car, or the two ends of the safety circuit can be extended along the length of the track, leaving an inertial buffer length for the car from the start of braking to the final stop. Through the above methods, while ensuring the safety of the car, the distance between the car and the car leveling at the landing can be reduced, thus reducing the overall track length occupied by the car and the adjacent leveling car, and improving the car's operating efficiency.

[0040] In other words, the position of the connecting device refers to its position relative to the car when it is connected to the safety node pool. A safety node refers to a necessary safety switch that needs to be detected; the set of these safety switches is called the safety node pool. For more details, please refer to the applicant's patent applications No. 202111337196X and 2020112707004.

[0041] The above solution will be further illustrated by an example below.

[0042] like Figure 1 and 2 As shown, two adjacent cars on the track are car M and car N, with car M located above car N. Both car M and car N are equipped with two parallel connecting devices. The two connecting devices on each car are a first connecting device A and a second connecting device B, with the first connecting device A located above the second connecting device B. Each connecting device on each car is also connected in series with a switch.

[0043] Car N stops at the second floor. At this time, the safety circuit connected to the landing door switch on the second floor is open, while other safety circuits are connected. When car M moves downwards, the switch connected in series with the second connecting device B on car M closes, and the switch connected in series with the first connecting device A opens. That is, the second connecting device B can be connected in series with the safety circuit, but the first connecting device A cannot. During the descent of car M, the second connecting device B of car M sequentially connects to the other safety circuits it passes through. These other safety circuits are connected and do not affect the normal operation of car M. When car M reaches above car N, the second connecting device B of car M connects to the safety circuit corresponding to the second floor. That is, the safety circuit connected to car M is now open, and the controller stops car M, preventing it from continuing to descend. At this time, car M will not collide with car N. When car M stops, the safety circuit connected to the first connecting device A and its corresponding switch is different from the safety circuit connected to the second connecting device B. The safety circuit connected to the first connecting device A and its corresponding switch is connected, but because the switch connected to the first connecting device A is disconnected, the first connecting device A cannot be connected to the safety circuit.

[0044] When the car M moves upward, the controller controls the switch connected in series with the first connecting device A on the car M to close and the switch connected in series with the second connecting device B to open. At this time, the first connecting device A is connected in another safety circuit, and the controller controls the car M to move upward.

[0045] As can be seen from the above, after the car M descends to the set distance above the car N, it can no longer descend, but it can ascend.

[0046] Finally, it is necessary to state that the above embodiments are only used to further illustrate the technical solution of the present invention in detail, and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A method for early detection of landing door opening and closing in a multi-car parallel elevator system, the elevator system comprising at least two vertical tracks, at least one switching device, and at least two self-driven cars that can smoothly switch between the two tracks via the switching device, the elevator system comprising a control system, characterized in that, Each landing door is equipped with a landing door switch to indicate whether the landing door is open or closed. Each landing door switch is connected to a safety circuit. All landing door switches belong to more than one safety circuit. Each safety circuit is equipped with at least one landing door switch. Each safety circuit is independent of the others. The car is equipped with a connection device for connecting to the safety circuit. Each of the cars is provided with a connecting device, which is movably mounted on the car; or each of the cars is provided with at least two connecting devices, and all the connecting devices on each car are configured such that only one connecting device can be connected to the safety circuit at a time. When the safety circuit of the landing door switch corresponding to a certain hall door on a certain floor is disconnected, the connecting device on the car running towards this hall door is connected to the safety circuit of the landing door switch corresponding to this hall door in advance. When the disconnection of the safety circuit is detected, the car is stopped and stops above or below the floor corresponding to this hall door, and cannot enter this floor. When the landing door switch is closed, the safety circuit is connected; when the landing door switch is open, the safety circuit is disconnected. When the safety circuit connected to the connecting device is connected, the control system controls the car where the connecting device is located to operate normally. When the safety circuit connected to the connecting device is disconnected, the control system controls the car where the connecting device is located to stop.

2. The method according to claim 1, characterized in that, After the car stops, it can switch from being connected to one safety circuit to being connected to another safety circuit.

3. The method according to claim 1, characterized in that, The connection device for accessing the safety circuit on a car is located at the front of the car or at the front end of the car along the current direction of car travel.

4. The method according to claim 1, 2, or 3, characterized in that, Each car is equipped with at least two connecting devices, which are connected in parallel.

5. The method according to claim 4, characterized in that, Each car is equipped with at least two connecting devices and at least two switches. Each connecting device and a switch are connected in series. The connecting device and the switch connected in series with it are connected to or disconnected from the safety circuit as a whole. When the switch is closed, the connecting device is connected to the safety circuit. When the switch is open, the connecting device cannot be connected to the safety circuit.

6. The method according to claim 5, characterized in that, The control system controls the switches to close or open. In the current direction of travel of the car, the switch connected in series with one of the connecting devices located at the front or foremost end of the car is closed, while the switches connected in series with the other connecting devices on the car are opened.

7. The method according to claim 1, characterized in that, Each safety circuit has at least two door switches connected in series.

8. The method according to claim 1, characterized in that, The connecting device is a current collector.

Images