Escalator key component bolt loosening effectiveness monitoring device

Abstract

The utility model discloses an escalator key component bolt looseness online effectiveness monitoring device, relates to the field of escalator bolt looseness monitoring, can monitor the fastening and looseness degree of a fastening bolt online in real time, and provides portability for daily maintenance and regular inspection of an escalator. According to the online validity monitoring device for bolt looseness of the key component of the escalator, a bolt head side vibration sensor is arranged on the bolt head side of a monitored bolt, a nut end side vibration sensor is arranged on the nut side, and bolt looseness vibration signals of a fastening nut are collected; the method comprises the following steps: receiving a vibration signal, performing amplification and analog-to-digital conversion transmission on the vibration signal through acquisition end hardware, performing signal filtering through two filters, namely an FIR filter 1 and an FIR filter 2, in an FPGA system, performing vibration data processing and sorting functions, and finally uploading the vibration data to an upper computer system through receiving end hardware and a CAN bus for data calculation processing. And extracting the loosening characteristic quantity of the bolt to analyze and judge the fastening and loosening conditions of the bolt.

Description

Technical Field

[0001] The utility model belongs to the technical field of escalator bolt loosening monitoring, and in particular relates to an online effectiveness monitoring device for the loosening of bolts of key components of an escalator. Background Art

[0002] Bolts play an important role as connectors and fasteners for many mechanical products and structures. Bolt connections under normal working conditions can reliably complete the load transfer between the connected structures, but under the action of vibration, the loosening of bolts causes the decrease in preload, which seriously endangers the safety and reliability of the overall structure and causes serious accidents when riding escalators.

[0003] For example, in 2010, the elevator at Guomao Station on Shenzhen Metro Line 1 slipped down due to loose main unit fixing bolts, and the accident caused 25 people to be injured; in 2011, the "7.5" Otis escalator accident on Beijing Metro Line 4 caused one death and multiple injuries. According to the investigation results of the accident investigation team, the main cause of the accident was that during the operation of the escalator, the fixing bolts of the driving main unit loosened and then broke, causing the main unit to overturn and lead to the accident.

[0004] Traditionally, the method of manually judging whether the bolts are tightened to determine whether there are any problems with the connection has been limited by the working space of the equipment, the inability of manual real-time monitoring for a long time, and certain working environments that are harmful to the inspectors. Therefore, there is an urgent need for a new method of online monitoring of bolt loosening with an intelligent system to achieve high real-time performance, avoid accidents, and ensure the safety of passengers and pedestrians. Utility Model Content

[0005] The purpose of this utility model patent is to be able to monitor the degree of tightening and loosening of fastening bolts in real time online when the escalator is in operation, especially to provide convenience for daily maintenance, repair and regular inspection of escalators, and improve the efficiency of inspection and testing work.

[0006] The utility model aims to provide a device for monitoring the loosening of bolts of key components of an escalator, which is mainly composed of four parts: an acquisition hardware module, an FPGA system, a receiving end hardware and a host computer system, and can accurately monitor the tightness of bolts at key parts of an escalator.

[0007] In order to achieve the above object, the technical solution of the utility model is:

[0008] The online effectiveness monitoring device for bolt loosening of key components of escalator, firstly, selects the bolts to be monitored of the key components of escalator, uses the vibration sensor in the acquisition end hardware to monitor the signal of bolt loosening, the bolt head side vibration sensor is installed on the bolt head side of the monitored bolt, and the nut end side vibration sensor is installed on the nut side, collects the vibration signal of the bolt loosening of the fastening nut, amplifies the vibration signal through the analog amplification signal module, and then performs analog-to-digital conversion through the AD sampling module and transmits it to the AD sampling driver, performs signal filtering through two-way filters FIR filter I and FIR filter II in the FPGA system, and performs vibration data processing and sorting function, finally uses the receiving serial port end hardware and CAN bus to upload to the upper computer system for data calculation and processing, extracts the bolt loosening feature quantity to analyze and judge the bolt tightening and loosening conditions.

[0009] Preferably, the vibration sensor is used to monitor the signal of bolt loosening, the bolt head side vibration sensor is installed on the bolt head side, and the nut end side vibration sensor is installed on the nut side, to collect the vibration signal of the bolt loosening that tightens the nut.

[0010] Preferably, the degree of tightening and loosening of bolts at key parts of the escalator is monitored online in real time, and the loosening of the bolts is determined through data processing, feature extraction and calculation analysis.

[0011] The main functions of the FPGA system module include: driving and controlling the AD chip to ensure that the sampling rate and sampling interval of the sampling signal meet the filter requirements; digital filtering of the vibration signal to filter out high-order harmonics; caching of the two signal data streams to meet the requirements of the subsequent transmission; and corresponding configuration guidance and control of the CAN bus controller to obtain the sending and receiving functions of data packets during data transmission.

[0012] The bolt head side vibration sensor is installed on the bolt head side of the monitored bolt, and the nut end side vibration sensor is installed on the nut side to collect the vibration signal of the loosening bolt that tightens the nut. The two sets of vibration signals collected are respectively passed through the analog amplification module to amplify the weak vibration signal, which is conducive to the next step of data processing.

[0013] The collected bolt vibration amplified signal is converted into a digital signal by the AD sampling module on the acquisition end hardware, uploaded to the AD sampling module in the FPGA system for analog-to-digital conversion, and integrated into a continuous vibration data signal.

[0014] After the vibration data is converted from AD, there are signals of external environmental interference in the data. FIR filter I is used to filter the vibration signal on the nut side, and FIR filter II is used to filter the vibration signal on the bolt head side to filter out the interference signal in the vibration data, which is beneficial to the subsequent data volume feature extraction.

[0015] The main function of the CAN bus system is to send and receive data packets in the form of CAN bus messages, so that the data transmission system has the advantages and indicators of the CAN bus, and convert the messages sent by CAN into serial port data at the receiving end and send them to the PC host computer.

[0016] The CAN bus is used to connect the FPGA system, the acquisition end hardware and the receiving end hardware for data transmission. The CAN bus is used here for the stability of system communication.

[0017] The host computer system has the functions of data caching, data extraction and reorganization, bolt loosening feature quantity, data phase difference calculation and analysis, and related data display and storage. The characteristic values ​​of bolt looseness in different degrees are extracted according to the frequency of vibration, and the results of the measured bolt looseness are obtained through analysis and calculation.

[0018] Method for implementing the phase difference algorithm of the vibration signals on both sides of the bolt:

[0019] Step S1, in the process of extracting the cache data of the host computer, extract m times, each extraction is a sampling, and the number of sampled data is W+1 data values, where W is the number of sampling points in one cycle of the signal in theory; the following steps are included in the process of calculating the phase difference by single sampling: in the cache data within the next second, perform this algorithm operation m times in total;

[0020] Step S2: Calculate a by applying formula (1) from the sampling starting point j=1 k (0); Formula (2) calculates b k (0), where a k With b k are the real and imaginary parts of the kth harmonic respectively, and f(i) is the value of the i-th sampling point;

[0021]

[0022]

[0023] Step S3: Change the sampling point starting point to j=1, and apply (1) and (2) again to calculate a k (1) and b k (1);

[0024] Step S4, applying the following formula (3) to obtain the frequency drift value m1 of the signal;

[0025]

[0026] Step S5: The calculation of the above process completes the calculation of the relevant parameters of the fundamental wave, and the calculation of the relevant parameters of the multiple harmonics is completed by applying formulas (4), (5), and (6):

[0027] m k =km1 (4)

[0028]

[0029]

[0030] Step S6, (Since this application is a real-time monitoring system, a compromise must be made between real-time performance and accuracy, so this method only calculates the second harmonic parameters) (5) The process only undergoes one operation. After obtaining the relevant fundamental wave parameters and first harmonic parameters, the amplitude and initial phase of the fundamental wave and the first harmonic need to be determined; use formula (7) to determine the amplitude A K , formula (8) determines its initial phase φ k ; This system only determines the amplitude and initial phase of the fundamental wave and the second harmonic:

[0031]

[0032]

[0033] Step S7: After completing the above steps and calculating the harmonic parameter A of the signal k With φ k Then, the Newton iteration method is used to find the initial phase of the signal; in the first iteration, let φ m =φ1, get the initial phase φ of the first sampling m1 , that is: the obtained parameter A k With φ k Substituting into equations (9) and (10), we get the initial phase with lower accuracy. Then, we iterate through equation (11) to improve its accuracy. Similarly, in order to improve the real-time performance, this system adopts three iterations to get the initial phase φ1 of a single column signal with relatively high accuracy:

[0034]

[0035]

[0036] Initially, let φ m =φ1, where φ1 is the initial phase of the fundamental wave; Substitute it into formulas (9) and (10) to calculate f(φi) and f′(φi), and then substitute it into the following formula to obtain φ i+1 , where i is the number of iterations:

[0037]

[0038] After reaching the new φ value, repeat the above iterative process until φ i+1 -φ i The value of satisfies the accuracy requirement set by the system; at this time, the initial phase value of this signal with higher accuracy is obtained;

[0039] Step S8, after the initial phase φ of the two columns of signals is obtained, the difference is obtained by using formula (12); in this case, φ1 and φ2 represent the initial phases of the two columns of signals respectively, and are different from the previous steps in representing the initial phases of the fundamental wave and the second harmonic; at this time, the phase difference calculation of one extraction sampling is completed:

[0040] Δφ=φ1-φ2 ​​(12);

[0041] Step S9: Since there are m extracted samples in the one-second cache data, the above process is repeated m times; the phase difference of the m segments of the two columns of sampled signals is calculated respectively; the average phase difference in this one-second process is calculated using formula (13); where Δφ i is the phase difference value of the i-th segment; so far, the average phase difference in one second can be calculated:

[0042]

[0043] The beneficial effects of the utility model are:

[0044] The online effectiveness monitoring device for bolt loosening of key components of escalator first selects the bolts to be monitored of the key components of escalator, uses the vibration sensor in the acquisition end hardware to monitor the signal of bolt loosening, the bolt head side vibration sensor is installed on the bolt head side of the monitored bolt, and the nut end side vibration sensor is installed on the nut side, collects the vibration signal of the bolt loosening of the fastening nut, amplifies the vibration signal through the analog amplification signal module, and then performs analog-to-digital conversion through the AD sampling module and transmits it to the AD sampling driver, performs signal filtering through two-way filters FIR filter I and FIR filter II in the FPGA system, and performs vibration data processing and sorting functions, finally uses the receiving serial port end hardware and CAN bus to upload to the upper computer system for data calculation and processing, extracts the bolt loosening feature quantity to analyze and judge the bolt tightening and loosening conditions, and outputs the detection result of each group of bolt tightness, which can improve work efficiency and has good practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 Schematic diagram of bolt connection structure of key components;

[0046] Figure 2 Structure diagram of the escalator component bolt loosening monitoring device;

[0047] Figure 3 Function diagram of bolt loosening monitoring of key components of escalator;

[0048] Figure 4 Flowchart of software for monitoring loose bolts of key escalator components. DETAILED DESCRIPTION

[0049] The utility model is described in detail below with reference to the accompanying drawings and specific implementation modes.

[0050] The utility model provides a system device for detecting loose bolts of key components of an escalator:

[0051] Figure 1 Schematic diagram of bolt connection structure of key components. Nut side 1, bolt head side 2, nesting part 3, washer 4, bolt head 5, nut 6, use bolts to fasten nut side 1 and bolt head side 2 together to prevent loosening and cause dangerous conditions, in order to monitor bolt loosening.

[0052] Figure 2 Structural diagram of the bolt loosening monitoring device for escalator components, acquisition end hardware 7: bolt head side vibration sensor, nut end side vibration sensor, analog amplifier module, AD sampling module, CAN controller and transceiver; FPGA system 8: AD sampling drive, FIR filter I, FIR filter II, data sorting, CAN drive control module; receiving end hardware 9: CAN controller and transceiver, serial port transmission; host computer system 10: data cache, data extraction and reorganization, data analysis and calculation, bolt loosening feature quantity, related data display and storage function; use the bolt head side vibration sensor and the nut end side vibration sensor to collect the bolt vibration signal of the fastener, then amplify and convert the analog to digital through the analog amplifier module and the AD sampling module, input it into the FPGA system 8 for a series of data processing, and transmit the signal to the host computer system 10 through the receiving end hardware 9, the CAN controller and transceiver and the serial port transmission for two signal phase calculation and analysis processing.

[0053] Figure 3The function diagram of bolt loosening monitoring of key components of escalator includes a function module 11 for monitoring bolt loosening of key components of escalator, a user management module 12, a user login module 13, a function interface selection module 14, a file reading module 15, a signal display module 16, a loosening feature analysis module 17, an AI intelligent diagnosis module 18, and a loosening result display module 19; the user login module 13 in the function module 11 for monitoring bolt loosening of key components of escalator is a user who can click to enter the operation interface, the user of the user management module 12 can use this module to configure the system connection debugging and parameters before use, the user of the function interface selection module 14 can use this column to click to find the function to be found, the file reading module 15 automatically reads the data collected by the vibration sensor and displays the real-time image data on the system display interface, the signal display module 16 and the loosening feature analysis module 17 are for displaying the vibration waveform and the historical data line chart, the AI ​​intelligent diagnosis module 18 is for diagnosing the vibration signals on both sides of the collected bolts, judging whether the bolts are loose and the degree of looseness, and then the monitoring results can be displayed in real time on the loosening result display module 19.

[0054] Figure 4 Flow chart of the bolt loosening monitoring software for key components of escalator; Data collection in the host computer system 20: First start data collection, initialize data cache, initialize data controls, select serial port number, set serial port parameters, open the serial port, wait for data reception, determine whether data is received, if no data is received, continue to return to wait for data reception, and perform the next step of data calculation and analysis 21 after receiving the data; In the data calculation and analysis 21, first parse the data, cache the data, read the cached data according to the algorithm requirements, call the algorithm to calculate the phase difference, filter the data, save the phase difference data, and then start to determine whether it is greater than the threshold, diagnose whether the bolt is tight or loose, and perform calculation processing and analysis The data result is sent to the display module 22 of the next step; in the display module 22, the sub-interface is opened, and real-time data display can be received, and cached data can be directly read, and the data is displayed on the display module. The data is judged whether to save the data, which can be divided into saving the data to the specified directory and returning to directly read the cached data; the historical phase difference curve is displayed on the display module, and the corresponding file is read to determine whether the file data is valid. If invalid, it returns to read the corresponding file, or enters the initialization drawing control to display the historical phase difference waveform curve; then the real-time vibration waveform is displayed, the waveform drawing control is initialized, the cached data is directly read, and the real-time vibration curve is displayed.

[0055] The working process of a bolt loosening detection system device for key components of an escalator provided by the embodiment of the utility model is as follows:

[0056] The online effectiveness monitoring device for bolt loosening of key components of escalator, firstly, selects the bolts to be monitored of the key components of escalator, uses the vibration sensor in the acquisition end hardware to monitor the signal of bolt loosening, the bolt head side vibration sensor is installed on the bolt head side of the monitored bolt, and the nut end side vibration sensor is installed on the nut side, collects the vibration signal of the bolt loosening of the fastening nut, amplifies the vibration signal through the analog amplification signal module, and then performs analog-to-digital conversion through the AD sampling module and transmits it to the AD sampling driver, performs signal filtering through two-way filters FIR filter I and FIR filter II in the FPGA system, and performs vibration data processing and sorting function, finally uses the receiving serial port end hardware and CAN bus to upload to the upper computer system for data calculation and processing, extracts the bolt loosening feature quantity to analyze and judge the tightening and loosening of the bolt, outputs the detection result of the tightness of each group of bolts, and uses the phase difference algorithm of the vibration signal on both sides of the bolt to compare and analyze the difference of the vibration signal on both sides of the nut and the screw of the bolt. The monitoring results of loose bolts of key components of escalator can be displayed on the upper computer monitoring system. On the function module of loose bolts monitoring of key components of escalator, users can click to enter the operation interface. Users can use the user management module to debug the system connection and configure the parameters before use. Users can select the module in this column through the function interface and click to find the function they need to find. The file reading module can automatically read the data collected by the vibration sensor and display the real-time image data on the system display interface. The signal display module and the loose feature analysis module display the vibration waveform and the historical data line chart. The AI ​​intelligent diagnosis module diagnoses the vibration signals on both sides of the collected bolts to determine whether the bolts are loose and the degree of looseness. Then the monitoring results can be displayed in real time on the loose result display module, which can effectively improve work efficiency and has good practical value.

[0057] The device for monitoring the effectiveness of bolt loosening of key components of an escalator provided by the embodiment of the utility model has a simple structure, high precision of bolt loosening detection result, easy operation, easy maintenance, low manufacturing cost and good practical value.

Claims

1. A device for monitoring the effectiveness of bolt loosening of key components of an escalator, characterized in that: include: Vibration sensor on the bolt head side, vibration sensor on the nut end side, acquisition end hardware, FPGA system, receiving end hardware and upper computer system display module; The bolt head side vibration sensor is installed on the bolt head side of the monitored bolt, and the nut end side vibration sensor is installed on the nut side. The loosening vibration signal of the bolt tightening the nut is collected, and the vibration signal is amplified and transmitted through the acquisition end hardware. In the FPGA system, the signal is filtered through two filters FIR filter I and FIR filter II, and the vibration data processing and sorting function is performed. Finally, the receiving end hardware and CAN bus are used to upload the data to the host computer system for data calculation and processing, and the bolt loosening feature quantity is extracted to analyze and judge the tightening and loosening of the bolt.

2. The device for monitoring the effectiveness of bolt loosening of key components of an escalator according to claim 1 is characterized in that: The bolt head side vibration sensor is placed on the bolt head side to collect vibration frequency data, and the nut end side vibration sensor is placed on the nut side to collect vibration frequency data.

3. The device for monitoring the effectiveness of bolt loosening of key components of an escalator according to claim 1 is characterized in that: The data collected by the vibration sensor on the bolt head side and the vibration sensor on the nut end side are respectively passed through the analog amplification module in the acquisition end hardware, and then through the AD sampling module for analog-to-digital conversion and transmitted to the AD sampling driver.

4. The device for monitoring the effectiveness of bolt loosening of key components of an escalator according to claim 1 is characterized in that: Also includes: User management module, user login module, function interface selection module, file reading module, signal display module, loose feature analysis module, AI intelligent diagnosis module, and loose result display module.

5. The device for monitoring the effectiveness of bolt loosening of key components of an escalator according to claim 1 is characterized in that: The data calculation and analysis module in the host computer system can judge whether the real-time data of the calculation result is greater than the threshold set by the system; When it is greater than the threshold, it means that the bolt has become loose; when it is less than the threshold, it means that the bolt has been in a tightened state.

6. The device for monitoring the effectiveness of bolt loosening of key components of an escalator according to claim 1 is characterized in that: The display module in the host computer system can display the data in the display data unit according to the data; open the secondary interface on the display module, which has a real-time data receiving unit display window and a specified path selection for saving data, a real-time vibration waveform display unit window and a real-time vibration curve display unit window, and a historical data search and historical phase difference waveform curve display unit window.

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