Elevator Flexible Body Monitoring System

Abstract

This invention discloses an elevator flexible body monitoring system, comprising: a detection unit connected to the end of the flexible body, used to detect the force exerted on the detection unit by the portion of the flexible body located below the detection unit; a first acquisition unit used to acquire the elevator car position; a calculation unit used to calculate a reference value based on the elevator car position, the reference value being the force exerted on the detection unit by the portion of the flexible body located below the detection unit when the flexible body is not abnormal; a first determination unit used to determine a reference range based on the reference value; and a judgment unit used to determine that the flexible body is not abnormal when the detection result of the detection unit is within the reference range, otherwise determining that the flexible body is abnormal. The elevator flexible body monitoring system of this invention can timely and accurately detect abnormalities such as hooking and entanglement between the flexible body in the elevator system and other devices in the shaft.

Description

Technical Field

[0001] This invention relates to the field of elevator technology, and specifically to a monitoring system for detecting the safety of flexible components such as traveling cables and compensating chains in an elevator system during the elevator car's vertical movement in the shaft. Background Technology

[0002] In elevator systems, a traveling cable is typically used to transmit electrical energy and signals between the elevator control cabinet and the car. Simultaneously, a compensating chain is usually installed to eliminate imbalances caused by the weight of the main elevator rope. Both the traveling cable and the compensating chain share several common characteristics: 1) they are both flexible materials that can be bent at will; 2) one end is fixed to the bottom of the car; 3) during elevator operation, they may sway due to building vibrations (such as earthquakes or strong winds). This swaying can cause the flexible materials to hook or become entangled with other devices in the hoistway. Such hooking or entanglement can lead to the flexible materials breaking due to excessive stress or seriously threaten the safety of elevator operation. Therefore, it is necessary to monitor in real time any abnormalities such as hooking or entanglement between the flexible materials (e.g., the traveling cable and compensating chain) and other devices in the elevator system.

[0003] To address the aforementioned problem of anomaly monitoring in flexible structures, Reference 1 (CN202310680547.X) proposes: setting the load applied to the car by the compensating chain when the unmanned car is on the top floor as the first reference value, and setting the load applied to the car by the compensating chain when the unmanned car is on the bottom floor as the second reference value. When the actual load applied to the car by the compensating chain during elevator operation exceeds the second reference value, it is considered that the compensating chain has experienced a jamming anomaly; when the actual load applied to the car by the compensating chain during elevator operation is less than the first reference value, it is considered that the compensating chain has experienced a cutting anomaly. Although this scheme can detect jamming and cutting anomalies of the compensating chain using the actual load value applied to the car by the compensating chain, the setting method of the first and second reference values ​​as the judgment criteria shows that the judgment criteria are very conservative, which leads to the following drawbacks:

[0004] 1. The possibility of missed detection is very high. For example, when the compensation chain is cut off abnormally, if the part of the compensation chain under the car after the cut is very long, that is, the ratio between the distance between the break point and the end point on one side of the car and the total length of the compensation chain is close to 1, then the scheme in Reference 1 will have missed detection.

[0005] 2. Low timeliness of detection. For example, when the car is ascending from a lower position in the hoistway and a jamming anomaly occurs, the load applied to the car by the portion of the compensating chain located at the bottom of the car is much smaller than the first reference value. Therefore, the tension generated by the jamming anomaly is relatively small at the beginning. The sum of this tension and the load applied to the car by the portion of the compensating chain located at the bottom of the car is still less than the first reference value. Therefore, the detection system cannot detect the jamming anomaly immediately. It needs to wait until the car continues to ascend, allowing the tension to increase until the sum of this tension and the load applied to the car by the portion of the compensating chain located at the bottom of the car reaches the first reference value before it can be detected. Such a detection delay may lead to more serious consequences caused by the anomaly.

[0006] Therefore, how to detect abnormalities such as hooking and entanglement between the flexible body in the elevator system and other devices in the shaft in a timely and accurate manner has become a technical problem to be solved. Summary of the Invention

[0007] The technical problem to be solved by this invention is how to detect in a timely and accurate manner any abnormalities such as hooking or entanglement between the flexible body in the elevator system and other devices in the shaft.

[0008] To address the aforementioned technical problems, this invention discloses an elevator flexible body monitoring system, comprising: a detection unit connected to the end of the flexible body, used to detect the force exerted on the detection unit by the portion of the flexible body located below the detection unit; a first acquisition unit used to acquire the elevator car position; a calculation unit used to calculate a reference value based on the elevator car position, the reference value being the force exerted on the detection unit by the portion of the flexible body located below the detection unit when the flexible body is not abnormal; a first determination unit used to determine a reference range based on the reference value; and a judgment unit used to determine that the flexible body is not abnormal when the detection result of the detection unit is within the reference range, otherwise determining that the flexible body is abnormal.

[0009] Preferably, the calculation unit calculates the reference value according to the following steps:

[0010] Step T1: Determine the first length of the portion of the flexible body located below the detection unit based on the position of the elevator car;

[0011] Step T2: Calculate the first mass of the portion of the flexible body located below the detection unit based on the linear density of the flexible body and the first length;

[0012] Step T3: Calculate the gravity acting on the portion of the flexible body located below the detection unit based on the first mass;

[0013] Step T4: Use the gravity as the reference value and output it.

[0014] Preferably, the first determining unit offsets the reference value by a preset offset along at least one offset direction by a preset offset amount, and determines the reference range according to the offset direction.

[0015] Preferably, when the offset is made in only one direction, the first determining unit takes the interval formed by the reference value and the point where the offset is located as the reference range; when the offset is made in two directions at the same time, the first determining unit takes the interval formed by the point where the reference value is located after the offset as the reference range.

[0016] Preferably, when the monitoring result is greater than the first boundary, the judgment unit determines that the flexible body has a stuck abnormality; when the monitoring result is less than the second boundary, the judgment unit determines that the flexible body has a disconnected abnormality; when the monitoring result is between the first boundary and the second boundary, the judgment unit determines that the flexible body has no abnormality; the first boundary is the larger of the two boundaries of the reference range, and the second boundary is the smaller of the two boundaries of the reference range.

[0017] Preferably, the elevator flexible body monitoring system further includes: a second acquisition unit for acquiring the acceleration and direction of movement of the elevator car; and a first adjustment unit for adjusting the reference value output by the calculation unit and / or the detection result of the detection unit according to the acceleration and direction of movement.

[0018] The first adjustment unit adjusts the reference value as follows: First, it calculates the adjustment force using Newton's second law based on the first mass and the acceleration. Then, when the direction of movement is upward, the sum of the reference value and the adjustment force is used as the adjusted reference value. When the direction of movement is downward, the difference between the reference value and the adjustment force is used as the adjusted reference value.

[0019] The first adjustment unit adjusts the detection result as follows: First, it calculates the adjustment force based on the first mass and the acceleration using Newton's second law. Then, when the direction of movement is upward, it subtracts the adjustment force from the detection result as the adjusted detection result. When the direction of movement is upward, it uses the sum of the detection result and the adjustment force as the adjusted detection result.

[0020] Preferably, the elevator flexible body monitoring system further includes: a second determining unit, used to determine whether the flexible body is swaying based on the detection result of the detection unit, and further determine the swaying condition of the flexible body when swaying is determined; and a second adjusting unit, used to adjust the reference range and / or the detection result of the detection unit based on the swaying condition of the flexible body.

[0021] Preferably, the second determining unit determines whether the flexible body is swaying according to the following steps, and further determines the swaying condition of the flexible body when swaying is determined:

[0022] Step 1: Select a specific time period;

[0023] Step 2: Determine the position of the first elevator car at the start time and the position of the second elevator car at the end time corresponding to the specified time period;

[0024] Step 3: Calculate the difference between the position of the first elevator car and the position of the second elevator car, and use the difference as the change in the first length of the part of the flexible body located below the detection unit during the specified time period;

[0025] Step 4: Calculate the corresponding change in gravity using the linear density of the flexible body and the change in the first length of the portion of the flexible body located below the detection unit during the specified time period;

[0026] Step 5: Subtract the change in gravity from the detection results within the specified time period, and use the resulting difference as the first difference;

[0027] Step 6: Determine the constant component in the first difference, and subtract the constant component from the first difference to obtain the second difference;

[0028] Step 7: When the second difference exceeds the threshold, it is determined that the flexible body is shaking; otherwise, it is determined that there is no shaking.

[0029] Step 8: When the swaying of the flexible body is determined in step 7, the swaying condition of the flexible body is determined based on the second difference.

[0030] Preferably, the length of the specified time period is such that the second difference contains at least one complete positive value portion and one connected complete negative value portion.

[0031] Preferably, the swaying condition includes the swaying amplitude, and the second adjustment unit first determines the two boundaries of the reference range, and then pushes the two boundaries in the direction of expanding the reference range, and the pushing distance is the sum of the swaying amplitude and a non-negative adjustment margin, thereby realizing the adjustment of the reference range.

[0032] Preferably, the shaking condition includes a shaking period, and the second adjustment unit adjusts the detection result of the detection unit according to the shaking period as follows:

[0033] The first position in the swaying period of the flexible body is determined at the current moment. The swaying change of the detection result at the current moment is determined based on the first position. The difference between the detection result at the current moment and the swaying change of the detection result is taken as the final detection result at the current moment. The swaying change of the detection result is the difference between the detection result of the flexible body when there is swaying and the detection result when there is no swaying.

[0034] Preferably, the second adjustment unit determines the amount of fluctuation in the detection result at the current moment according to the following steps:

[0035] Step S1: Determine the detection result corresponding to the first position within the swaying cycle of the flexible body;

[0036] Step S2: Subtract the constant component of the swaying period from the detection result corresponding to the first position to obtain the first difference;

[0037] Step S3: Determine the moment corresponding to the first position within the swaying period of the flexible body, and take it as a specific moment;

[0038] Step S4: Use the specific time and the current time as the designated time period;

[0039] Step S5: Determine the position of the first elevator car at the start time and the position of the second elevator car at the end time corresponding to the specified time period;

[0040] Step S6: Calculate the difference between the first elevator car position and the second elevator car position, and use the difference as the change in the first length of the portion of the flexible body located below the detection unit during the specified time period;

[0041] Step S7: Calculate the corresponding change in gravity using the linear density of the flexible body and the change in the first length of the portion of the flexible body located below the detection unit during the specified time period;

[0042] Step S8: Calculate the change in gravity between a specific moment and the current moment using the change in the linear density of the flexible body and the change in the first length of the portion of the flexible body located below the detection unit during the specified time period;

[0043] Step S9: Subtract the gravity change obtained in step S5 from the first difference, and use the resulting difference as the shaking change of the detection result.

[0044] The present invention also provides an elevator flexible body monitoring system, comprising: a detection unit connected to the end of the flexible body for detecting the force exerted on the detection unit by the portion of the flexible body located below the detection unit; a third acquisition unit for acquiring the elevator car position; a reference value calculation unit for calculating a reference value based on the elevator car position information, wherein the reference value refers to the force exerted on the detection unit by the portion of the flexible body located below the detection unit when the flexible body is not abnormal; a difference calculation unit for obtaining a third difference value by subtracting the reference value from the detection result of the detection unit; and a judgment unit for determining that the flexible body is abnormal when the third difference value is greater than a third threshold value, otherwise determining that the flexible body is not abnormal, wherein the third threshold value is a positive real number.

[0045] Preferably, the elevator flexible body monitoring system further includes: a fourth acquisition unit for acquiring the acceleration of the elevator car; and a third adjustment unit for adjusting the third threshold according to the acceleration.

[0046] Preferably, the third adjustment unit calculates the adjustment force using Newton's second law based on the third mass and acceleration of the portion of the flexible body located below the detection unit, and uses the sum of the reference value and the adjustment force as the adjusted third threshold.

[0047] Preferably, the elevator flexible body monitoring system further includes: a fifth determining unit, used to determine whether the flexible body is swaying based on the detection result of the detection unit, and further determine the swaying situation of the flexible body when swaying is determined; and a fourth adjusting unit, used to adjust the third threshold according to the swaying situation of the flexible body.

[0048] Beneficial technical effects

[0049] The elevator flexible body monitoring system of the present invention can detect abnormalities such as hooking and entanglement between the flexible body in the elevator system and other devices in the shaft in a timely and accurate manner. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of the elevator flexible body monitoring system in Example 1;

[0051] Figure 2 This is a schematic diagram of the elevator structure when the flexible body is a traveling cable in Example 1;

[0052] Figure 3 This is a schematic diagram of the elevator structure when the flexible body is a compensation chain in Example 1. Detailed Implementation

[0053] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0054] Example 1

[0055] like Figure 1 As shown, this embodiment discloses an elevator flexible body monitoring system, including: a detection unit connected to the end of the flexible body, used to detect the force exerted on the detection unit by the portion of the flexible body located below the detection unit; a first acquisition unit used to acquire the elevator car position; a calculation unit used to calculate a reference value based on the elevator car position, the reference value being the force exerted on the detection unit by the portion of the flexible body located below the detection unit when the flexible body is not abnormal; a first determination unit used to determine a reference range based on the reference value; and a judgment unit used to determine that the flexible body is not abnormal when the detection result of the detection unit is within the reference range, otherwise determining that the flexible body is abnormal.

[0056] The calculation unit calculates the reference value according to the following steps: Step T1, determine the first length of the portion of the flexible body located below the detection unit based on the position of the elevator car; Step T2, calculate the first mass of the portion of the flexible body located below the detection unit based on the linear density of the flexible body and the first length; Step T3, calculate the gravity acting on the portion of the flexible body located below the detection unit based on the first mass; Step T4, output the gravity as the reference value.

[0057] The first determining unit offsets the reference value by a preset offset along at least one offset direction by a preset offset amount, and determines the reference range according to the offset direction.

[0058] Specifically, when the offset is only along one direction, the first determining unit takes the interval formed by the reference value and the point where it is located after the offset as the reference range; when the offset is simultaneously along two directions, the first determining unit takes the interval formed by the point where the reference value is located after the offset as the reference range.

[0059] When the monitoring result is greater than the first boundary, the judgment unit determines that the flexible body has a stuck abnormality; when the monitoring result is less than the second boundary, the judgment unit determines that the flexible body has a disconnected abnormality; when the monitoring result is between the first boundary and the second boundary, the judgment unit determines that the flexible body has no abnormality; the first boundary is the larger of the two boundaries of the reference range, and the second boundary is the smaller of the two boundaries of the reference range.

[0060] Taking flexible cables as an example, such as Figure 2As shown, the traction sheave 4 drives the car 1 and counterweight 3 to move up and down in the hoistway via the traction rope 2. One end of the traveling cable 6 is fixed to the fixing device 7 on the hoistway wall, and the other end is fixed to the bottom of the car via the detection unit 5. The detection unit 5 detects the force exerted on the car (or the detection unit 5) by gravity on the portion of the traveling cable 6 located below the car, and outputs the detection result corresponding to the force. Of course, the detection unit can also be installed on the fixing device 7 and used to detect the force exerted on the fixing device 7 (or the detection unit 5) by gravity on the portion of the traveling cable 6 located below the fixing device 7.

[0061] Taking a flexible body as a compensation chain as an example, such as Figure 3 As shown, one end of the compensation chain 6 is fixed to the lower part of the counterweight 3, and the other end is fixed to the bottom of the car 1 (or the detection unit 5) via the detection unit 5. The detection unit 5 detects the force exerted on the car (or the detection unit 5) by gravity on the portion of the compensation chain 6 located below the car, and outputs the detection result corresponding to the force. Of course, the detection unit 5 can also be located at the lower part of the counterweight 3 and be used to detect the force exerted on the counterweight 3 (or the detection unit 5) by gravity on the portion of the compensation chain 6 located below the counterweight 3.

[0062] For a detailed implementation of the detection department, please refer to reference 1. Figure 2 The corresponding explanations in Figure 4 and the instruction manual will not be repeated here.

[0063] The elevator flexible body monitoring system disclosed in this embodiment determines the reference value and reference range based on the elevator car position information, so that the reference range changes with the change of the elevator car position, which greatly improves the accuracy of the judgment reference for whether the flexible body has an abnormality. Therefore, it can significantly improve the accuracy and timeliness of whether the flexible body has hooked, entangled or other abnormalities.

[0064] Example 2

[0065] This embodiment is similar to Embodiment 1; the differences will be explained below.

[0066] The elevator flexible body monitoring system also includes:

[0067] The second acquisition unit is used to acquire the acceleration (positive acceleration indicates that the elevator car is accelerating, and negative acceleration indicates that the elevator car is decelerating) and direction of movement of the elevator car;

[0068] The first adjustment unit adjusts the reference value output by the calculation unit and / or the detection result of the detection unit based on the acceleration and the direction of movement;

[0069] The first adjustment unit adjusts the reference value as follows: First, it calculates the adjustment force using Newton's second law based on the first mass and the acceleration. Then, when the direction of movement is upward, the sum of the reference value and the adjustment force is used as the adjusted reference value. When the direction of movement is downward, the difference between the reference value and the adjustment force is used as the adjusted reference value.

[0070] The first adjustment unit adjusts the detection result as follows: First, it calculates the adjustment force based on the first mass and the acceleration using Newton's second law. Then, when the direction of movement is upward, it subtracts the adjustment force from the detection result as the adjusted detection result. When the direction of movement is upward, it uses the sum of the detection result and the adjustment force as the adjusted detection result.

[0071] The elevator flexible body monitoring system of this embodiment further considers the force exerted on the car by the flexible body during the acceleration or deceleration of the elevator (i.e., the force exerted on the detection unit by the part of the flexible body located below the detection unit). By adjusting the reference value (reference range) and / or detection results according to the acceleration, the accuracy and timeliness of detecting whether the flexible body has experienced abnormalities such as hooking or entanglement can be significantly improved.

[0072] Example 3

[0073] In reality, flexible structures installed in shafts will experience varying degrees of swaying due to factors such as strong winds and earthquakes causing structural swaying. Even without structural swaying, the mere movement of the car within the shaft can cause swaying in the flexible structure. This swaying indicates movement not only vertically but also horizontally. This horizontal movement creates the risk of snagging or entanglement with other components in the shaft. Therefore, it is precisely because of the swaying of the flexible structure that monitoring for anomalies such as snagging and entanglement becomes necessary. In other words, if the swaying is ignored, monitoring for anomalies such as snagging and entanglement is completely unnecessary. Reference 1 clearly implements anomaly monitoring for the compensation chain without considering the swaying of the flexible structure, leaving significant room for improvement in its approach.

[0074] Based on the aforementioned embodiments, this embodiment further considers the impact of the swaying of the flexible body on monitoring and provides an adjustment method based on sway compensation.

[0075] The elevator flexible body monitoring system in this embodiment also includes:

[0076] The second determining unit is used to determine whether the flexible body is swaying based on the detection result of the detection unit, and to further determine the swaying situation of the flexible body when swaying is determined.

[0077] The second adjustment unit is used to adjust the reference range and / or the detection result of the detection unit according to the swaying of the flexible body.

[0078] The second determining unit determines whether the flexible body is swaying according to the following steps, and further determines the swaying condition of the flexible body when swaying is determined:

[0079] Step 1: Select a specific time period;

[0080] Step 2: Determine the position of the first elevator car at the start time and the position of the second elevator car at the end time corresponding to the specified time period;

[0081] Step 3: Calculate the difference between the position of the first elevator car and the position of the second elevator car, and use the difference as the change in the first length of the part of the flexible body located below the detection unit during the specified time period;

[0082] Step 4: Calculate the corresponding change in gravity using the linear density of the flexible body and the change in the first length of the portion of the flexible body located below the detection unit during the specified time period;

[0083] Step 5: Subtract the change in gravity from the detection results within the specified time period, and use the resulting difference as the first difference;

[0084] Step 6: Determine the constant component in the first difference (e.g., calculate the mean, median, mean square, etc.), and subtract the constant component from the first difference to obtain the second difference;

[0085] Step 7: When the second difference exceeds the threshold, it is determined that the flexible body is shaking; otherwise, it is determined that there is no shaking.

[0086] Step 8: When the swaying of the flexible body is determined in step 7, the swaying condition of the flexible body is determined based on the second difference.

[0087] The length of the specified time period should be such that the second difference contains at least one complete positive value and one connected complete negative value; or further, the time interval between the endpoint closest to the current time and the current time is less than a time threshold.

[0088] The shaking condition includes the shaking amplitude, and the second adjustment unit first determines the two boundaries of the reference range, and then pushes the two boundaries in the direction of expanding the reference range, and the pushing distance is the sum of the shaking amplitude and a non-negative adjustment margin, thereby realizing the adjustment of the reference range.

[0089] The shaking condition includes a shaking period. The second adjustment unit adjusts the detection result of the detection unit according to the shaking period as follows: the first position in the shaking period is determined according to the shaking period of the flexible body, the shaking change of the detection result at the current time is determined according to the first position, and the difference between the detection result at the current time and the shaking change of the detection result is taken as the final detection result at the current time. The shaking change of the detection result is the difference between the detection result when the flexible body is shaking and the detection result when there is no shaking, that is, the part of the detection result corresponding to the shaking of the flexible body.

[0090] The second adjustment unit determines the amount of fluctuation in the detection result at the current moment according to the following steps:

[0091] Step S1: Determine the detection result corresponding to the first position within the swaying cycle of the flexible body;

[0092] Step S2: Subtract the constant component of the swaying period (e.g., calculate the average, median, mean square value, etc.) from the detection result corresponding to the first position to obtain the first difference;

[0093] Step S3: Determine the moment corresponding to the first position within the swaying period of the flexible body, and take it as a specific moment;

[0094] Step S4: Use the specific time and the current time as the designated time period;

[0095] Step S5: Determine the position of the first elevator car at the start time and the position of the second elevator car at the end time corresponding to the specified time period;

[0096] Step S6: Calculate the difference between the first elevator car position and the second elevator car position, and use the difference as the change in the first length of the portion of the flexible body located below the detection unit during the specified time period;

[0097] Step S7: Calculate the corresponding change in gravity using the linear density of the flexible body and the change in the first length of the portion of the flexible body located below the detection unit during the specified time period;

[0098] Step S8: Calculate the change in gravity between a specific moment and the current moment using the change in the linear density of the flexible body and the change in the first length of the portion of the flexible body located below the detection unit during the specified time period;

[0099] Step S9: Subtract the gravity change obtained in step S5 from the first difference, and use the resulting difference as the shaking change of the detection result.

[0100] Based on the aforementioned embodiments, the elevator flexible body monitoring system in this embodiment further considers the impact of the flexible body's swaying on the monitoring results of the detection unit, and uses the swaying situation to adjust the detection results and / or reference range. Therefore, it can more accurately and timely monitor the abnormalities of the flexible body.

[0101] Example 4

[0102] This embodiment provides an elevator flexible body monitoring system that differs from the previous embodiments, including...

[0103] A detection unit, connected to the end of the flexible body, is used to detect the force exerted on the detection unit by the portion of the flexible body located below the detection unit;

[0104] The third acquisition unit is used to acquire the position of the elevator car.

[0105] The reference value calculation unit calculates a reference value based on the elevator car position information. The reference value refers to the force exerted on the detection unit by the portion of the flexible body located below the detection unit when the flexible body is not abnormal.

[0106] The difference calculation unit subtracts the reference value from the detection result of the detection unit to obtain a third difference value;

[0107] The judgment unit determines that the flexible body is abnormal when the third difference (or its absolute value when the third difference is negative) is greater than the third threshold; otherwise, it determines that the flexible body is not abnormal. The third threshold is a positive real number.

[0108] Example 5

[0109] This embodiment, based on embodiment 4, further considers the influence of the car's angular velocity.

[0110] The elevator flexible body monitoring system also includes:

[0111] The fourth acquisition unit is used to acquire the acceleration of the elevator car;

[0112] The third adjustment unit adjusts the third threshold according to the acceleration.

[0113] The third adjustment unit calculates the adjustment force using Newton's second law based on the third mass and acceleration of the portion of the flexible body located below the detection unit, and uses the sum of the reference value and the adjustment force as the adjusted third threshold.

[0114] Example 6

[0115] This embodiment, based on embodiment 4 or 5, further considers the influence of flexible body sway.

[0116] The elevator flexible body monitoring system also includes:

[0117] The fifth determining unit is used to determine whether the flexible body is swaying based on the detection result of the detection unit, and to further determine the swaying condition of the flexible body when swaying is determined.

[0118] The fourth adjustment unit is used to adjust the third threshold according to the swaying of the flexible body.

[0119] The fifth determining unit determines whether the flexible body is swaying according to the following steps, and further determines the swaying situation of the flexible body when swaying is determined.

[0120] Step 1: Select a specific time period;

[0121] Step 2: Determine the position of the first elevator car at the start time and the position of the second elevator car at the end time corresponding to the specified time period;

[0122] Step 3: Calculate the difference between the position of the first elevator car and the position of the second elevator car, and use the difference as the change in the first length of the part of the flexible body located below the detection unit during the specified time period;

[0123] Step 4: Calculate the corresponding change in gravity using the linear density of the flexible body and the change in the first length of the portion of the flexible body located below the detection unit during the specified time period;

[0124] Step 5: Subtract the change in gravity from the detection results within the specified time period, and use the resulting difference as the first difference;

[0125] Step 6: Determine the constant component in the first difference, and subtract the constant component from the first difference to obtain the second difference;

[0126] Step 7: When the second difference exceeds the threshold, it is determined that the flexible body is shaking; otherwise, it is determined that there is no shaking.

[0127] Step 8: When the swaying of the flexible body is determined in step 7, the swaying condition of the flexible body is determined based on the second difference.

[0128] The shaking condition includes the shaking amplitude, and the fourth adjustment unit uses the sum of the shaking amplitude and the third threshold as the adjusted third threshold.

[0129] The elevator flexible body monitoring system disclosed herein is designed to monitor anomalies such as hooking and scraping of flexible bodies (mainly traveling cables or compensating chains) in elevator systems. The monitoring method involves using a detection unit to monitor the force exerted on the detection unit by gravity on the portion of the flexible body located below the detection unit, and then appropriately processing the detected force. Specifically, embodiments 1 and 4 implement flexible body anomaly monitoring based on car position information; embodiments 2 and 5 implement flexible body anomaly monitoring based on car position information and acceleration information; embodiment 3 implements flexible body anomaly monitoring based on car position information and flexible body swaying information; and embodiment 6 implements flexible body anomaly monitoring based on car position information, car acceleration information, and flexible body swaying information. Embodiment 3 is the first preferred embodiment of this application, implementing flexible body anomaly monitoring based on car position information, car acceleration information, and flexible body swaying information. Embodiments 1 and 2 are obtained by appropriate simplification of the first preferred embodiment. Embodiment 6 is the second preferred embodiment of this application, implementing flexible body anomaly monitoring based on car position information, car acceleration information, and flexible body swaying information.

[0130] Examples 4 and 5 are obtained by making appropriate simplifications based on the second best embodiment.

[0131] This application is very similar to Document 1 (202310680547.X) in the background art. Both are for monitoring abnormalities such as hooking and entanglement of flexible bodies (Document 1 is limited to compensation chains) in elevator systems. Both are based on the force exerted by the flexible body on the detection unit during hooking and other abnormalities—that is, the detection result of the detection unit—to achieve abnormal monitoring of the flexible body. The difference is that Document 1 uses the force exerted when the car is at the top and bottom of the hoistway as the benchmark value, while this application considers the influence of car position, car acceleration, and the swaying of the flexible body on the monitoring results. It uses car position, car acceleration, and the swaying of the flexible body to determine or adjust the benchmark range and / or monitoring results, thereby enabling more accurate and timely monitoring of abnormalities such as hooking of the flexible body.

Claims

1. An elevator flexible body monitoring system, characterized in that, include: A detection unit, connected to the end of the flexible body, is used to detect the force exerted on the detection unit by the portion of the flexible body located below the detection unit; The first acquisition unit is used to acquire the position of the elevator car. The calculation unit calculates a reference value based on the position of the elevator car. The reference value refers to the force exerted on the detection unit by the portion of the flexible body located below the detection unit when the flexible body is not abnormal. The first determining unit determines the reference range based on the reference value; The judgment unit determines that the flexible body is not abnormal when the detection result of the detection unit is within the reference range; otherwise, it determines that the flexible body is abnormal. The second determining unit is used to determine whether the flexible body is swaying based on the detection result of the detection unit, and to further determine the swaying situation of the flexible body when swaying is determined. The second determining unit determines whether the flexible body is swaying according to the following steps, and further determines the swaying condition of the flexible body when swaying is determined: Step 1: Select a specific time period; Step 2: Determine the position of the first elevator car at the start time and the position of the second elevator car at the end time corresponding to the specified time period; Step 3: Calculate the difference between the position of the first elevator car and the position of the second elevator car, and use the difference as the change in the first length of the part of the flexible body located below the detection unit during the specified time period; Step 4: Calculate the corresponding change in gravity using the linear density of the flexible body and the change in the first length of the portion of the flexible body located below the detection unit during the specified time period; Step 5: Subtract the change in gravity from the detection results within the specified time period, and use the resulting difference as the first difference; Step 6: Determine the constant component in the first difference, and subtract the constant component from the first difference to obtain the second difference; Step 7: When the second difference exceeds the threshold, it is determined that the flexible body is shaking; otherwise, it is determined that there is no shaking. Step 8: When the swaying of the flexible body is determined in step 7, the swaying condition of the flexible body is determined based on the second difference.

2. The elevator flexible body monitoring system according to claim 1, characterized in that, The calculation unit calculates the benchmark value according to the following steps: Step T1: Determine the first length of the portion of the flexible body located below the detection unit based on the position of the elevator car; Step T2: Calculate the first mass of the portion of the flexible body located below the detection unit based on the linear density of the flexible body and the first length; Step T3: Calculate the gravity acting on the portion of the flexible body located below the detection unit based on the first mass; Step T4: Use the gravity as the reference value and output it.

3. The elevator flexible body monitoring system according to claim 1, characterized in that, The first determining unit offsets the reference value by a preset offset along at least one offset direction by a preset offset amount, and determines the reference range according to the offset direction.

4. The elevator flexible body monitoring system according to claim 3, characterized in that, When the offset is made in only one direction, the first determining unit takes the interval formed by the reference value and the point where the offset is located as the reference range; when the offset is made in two directions at the same time, the first determining unit takes the interval formed by the point where the offset reference value is located as the reference range.

5. The elevator flexible body monitoring system according to claim 1, characterized in that, When the detection result is greater than the first boundary, the determination unit determines that the flexible body has a stuck abnormality; when the detection result is less than the second boundary, the determination unit determines that the flexible body has a disconnected abnormality. When the detection result is located between the first boundary and the second boundary, the judgment unit determines that the flexible body has no abnormality; The first boundary is the larger of the two boundaries of the reference range, and the second boundary is the smaller of the two boundaries of the reference range.

6. The elevator flexible body monitoring system according to claim 2, characterized in that, The elevator flexible body monitoring system also includes: The second acquisition unit is used to acquire the acceleration and direction of movement of the elevator car; The first adjustment unit adjusts the reference value output by the calculation unit and / or the detection result of the detection unit based on the acceleration and the direction of movement; The first adjustment unit adjusts the reference value as follows: First, it calculates the adjustment force using Newton's second law based on the first mass and the acceleration. Then, when the direction of movement is upward, the sum of the reference value and the adjustment force is used as the adjusted reference value. When the direction of movement is downward, the difference between the reference value and the adjustment force is used as the adjusted reference value. The first adjustment unit adjusts the detection result as follows: First, it calculates the adjustment force based on the first mass and the acceleration using Newton's second law. Then, when the direction of movement is upward, it subtracts the adjustment force from the detection result as the adjusted detection result. When the direction of movement is upward, it uses the sum of the detection result and the adjustment force as the adjusted detection result.

7. The elevator flexible body monitoring system according to claim 1 or 6, characterized in that, The elevator flexible body monitoring system also includes: The second adjustment unit is used to adjust the reference range and / or the detection result of the detection unit according to the swaying of the flexible body.

8. The elevator flexible body monitoring system according to claim 1, characterized in that, The length of the specified time period is such that the second difference contains at least one complete positive value portion and one complete negative value portion connected to it.

9. The elevator flexible body monitoring system according to claim 7, characterized in that, The shaking condition includes the shaking amplitude, and the second adjustment unit first determines the two boundaries of the reference range, and then pushes the two boundaries in the direction of expanding the reference range, and the pushing distance is the sum of the shaking amplitude and a non-negative adjustment margin, thereby realizing the adjustment of the reference range.

10. The elevator flexible body monitoring system according to claim 7, characterized in that, The shaking condition includes a shaking period, and the second adjustment unit adjusts the detection result of the detection unit according to the shaking period as follows: The first position in the swaying period of the flexible body is determined at the current moment. The swaying change of the detection result at the current moment is determined based on the first position. The difference between the detection result at the current moment and the swaying change of the detection result is taken as the final detection result at the current moment. The swaying change of the detection result is the difference between the detection result of the flexible body when there is swaying and the detection result when there is no swaying.

11. An elevator flexible body monitoring system, characterized in that, include: A detection unit, connected to the end of the flexible body, is used to detect the force exerted on the detection unit by the portion of the flexible body located below the detection unit; The third acquisition unit is used to acquire the position of the elevator car. The reference value calculation unit calculates a reference value based on the elevator car position information. The reference value refers to the force exerted on the detection unit by the portion of the flexible body located below the detection unit when the flexible body is not abnormal. The difference calculation unit subtracts the reference value from the detection result of the detection unit to obtain a third difference value; The judgment unit determines that the flexible body is abnormal when the third difference is greater than the third threshold; otherwise, it determines that the flexible body is not abnormal. The third threshold is a positive real number. The fifth determining unit is used to determine whether the flexible body is swaying based on the detection result of the detection unit, and to further determine the swaying condition of the flexible body when swaying is determined. The fifth determining unit determines whether the flexible body is swaying according to the following steps, and further determines the swaying situation of the flexible body when swaying is determined. Step 1: Select a specific time period; Step 2: Determine the position of the first elevator car at the start time and the position of the second elevator car at the end time corresponding to the specified time period; Step 3: Calculate the difference between the position of the first elevator car and the position of the second elevator car, and use the difference as the change in the first length of the part of the flexible body located below the detection unit during the specified time period; Step 4: Calculate the corresponding change in gravity using the linear density of the flexible body and the change in the first length of the portion of the flexible body located below the detection unit during the specified time period; Step 5: Subtract the change in gravity from the detection results within the specified time period, and use the resulting difference as the first difference; Step 6: Determine the constant component in the first difference, and subtract the constant component from the first difference to obtain the second difference; Step 7: When the second difference exceeds the threshold, it is determined that the flexible body is shaking; otherwise, it is determined that there is no shaking. Step 8: When the swaying of the flexible body is determined in step 7, the swaying condition of the flexible body is determined based on the second difference.

12. The elevator flexible body monitoring system according to claim 11, characterized in that, The elevator flexible body monitoring system also includes: The fourth acquisition unit is used to acquire the acceleration of the elevator car; The third adjustment unit adjusts the third threshold according to the acceleration.

13. The elevator flexible body monitoring system according to claim 12, characterized in that, The third adjustment unit calculates the adjustment force using Newton's second law based on the third mass of the portion of the flexible body located below the detection unit and the acceleration, and uses the sum of the reference value and the adjustment force as the adjusted third threshold.

14. The elevator flexible body monitoring system according to claim 11 or 12, characterized in that, The elevator flexible body monitoring system also includes: The fourth adjustment unit is used to adjust the third threshold according to the swaying of the flexible body.

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