Energy collecting device, scraper chain tension monitoring system and monitoring method

Abstract

The invention discloses an energy collecting device and a scraper chain tension monitoring system and method, and belongs to the technical field of scraper conveyors. The scraper chain tension monitoring system comprises a tension monitoring node and an aggregation node, and the tension monitoring node is installed on a scraper and comprises an energy collection device, an energy management module, a data processing module, a strain gauge and a wireless transceiver. An energy collection device, an energy management module, a data processing module and a wireless transceiver are mounted at each of the two ends of each scraper, and a strain gauge is mounted on the scraper chain; the energy management module is used for processing a voltage signal generated by the energy collection device; the data processing module is used for acquiring tension monitoring data of the strain gauges; and the wireless transceiver is used for transmitting the monitoring data acquired by the data processing module to the sink node. According to the invention, power can be supplied to the tension monitoring node through the energy collection device, and high-quality sustainable monitoring of the tension of the scraper chain can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of scraper conveyors, and in particular to an energy collection device, a scraper chain tension monitoring system and a monitoring method. Background Art

[0002] As an important load-bearing component of heavy-duty scraper conveyors, scraper chains are subjected to long-term heavy-load operation in harsh working conditions, and are prone to chain jams, chain breaks and other faults, which in turn affect the safety and efficiency of coal mine transportation. Scraper chain tension can intuitively reflect the tension of the scraper chain and directly characterize fault conditions such as chain jams / chain breaks. It is a key parameter for real-time monitoring of the scraper chain's operating status. Therefore, it is very necessary to study the scraper chain tension monitoring method. Wireless sensor networks have the advantages of self-power (battery installation) and flexible deployment. From a technical perspective, it has the potential to monitor scraper chain tension in real time. However, the mobility and complexity of the working conditions of the scraper chain pose great challenges to the energy supply and service quality assurance of the monitoring network. Specifically, the tension monitoring node needs to be attached to the scraper chain for embedded deployment, and the limited size of the scraper chain restricts the use of large-capacity node batteries. The mobility of the scraper chain makes it difficult to replace the batteries of the accompanying nodes in time, resulting in the node being unable to obtain continuous energy supply. The fully mechanized mining operation mode of underground coal mines determines that the scraper chain will dynamically switch between light-load and heavy-load conditions. The operating speed and failure rate are low when light-loaded, and the operating speed and failure rate are high when heavy-loaded. The node needs to have a sampling frequency adjustment mechanism that can adapt to different scraper chain working conditions. Therefore, it is urgent to carry out key technology research on scraper chain tension monitoring wireless sensor network nodes to achieve high-quality and continuous monitoring of the scraper chain status and ensure the safe operation of the scraper conveyor. Summary of the invention

[0003] In order to overcome the defects in the prior art, the present invention proposes an energy collection device, a scraper chain tension monitoring node and a monitoring method, which can, on the one hand, realize node self-powering, and on the other hand, perform high-quality sustainable monitoring of the scraper chain tension of the scraper conveyor, and combine the detection of the real-time speed of the scraper chain to realize adaptive adjustment of the node sampling frequency under different working conditions.

[0004] The technical solution adopted by the present invention is as follows: in the first aspect, the present invention proposes an energy collection device, including an energy application unit, including a passive roller, a ball, a bearing seat, a turntable and a main excitation magnet, wherein the rotating shaft on the passive roller is supported by two bearing seats; the turntable is installed at one end of the rotating shaft; at least one main excitation magnet is installed at the edge of the turntable surface; the ball is located below the passive roller, and the upper part is in frictional contact with the bottom of the passive roller, and the bottom receives the friction force to rotate, driving the passive roller to rotate, and then driving the main excitation magnet on the turntable to rotate;

[0005] The energy receiving unit comprises a bracket, a beam, a piezoelectric vibrator and an excited magnet, wherein one end of the beam is fixedly connected to the bracket, the other end is provided with the excited magnet, and the piezoelectric vibrator is provided in the middle;

[0006] The main exciting magnet rotates and generates mutual force when encountering the excited magnet, and the excited magnet vibrates up and down, driving the piezoelectric vibrator to vibrate and generate a periodic voltage signal.

[0007] As a further improvement of the present invention, there are two main excitation magnets, which are located at both ends of the diameter of the turntable.

[0008] As a further improvement of the present invention, the main exciting magnet and the excited magnet generate mutual attraction.

[0009] In a second aspect, the present invention proposes a scraper chain tension monitoring system, comprising a convergence node and a tension monitoring node, wherein the tension monitoring node is installed on a scraper; the tension monitoring node comprises the energy collection device, energy management module, data processing module, strain gauge and wireless transmitter and receiver described above; the energy collection device, energy management module, data processing module and wireless transmitter and receiver are installed at both ends of each scraper, and the strain gauge is installed on the scraper chain;

[0010] The energy management module is used to process the voltage signal generated by the energy collection device, and to sense the current running speed of the scraper chain by periodically monitoring the frequency of the piezoelectric vibrator power generation voltage;

[0011] The data processing module is used to collect the tension monitoring data of the strain gauge;

[0012] The wireless transmitter and receiver is used to transmit the tension monitoring data acquired by the data processing module to the aggregation node.

[0013] As a further improvement of the present invention, the bracket on the energy collection device is installed on a substrate, and a circular hole is opened on the substrate directly below the ball. The bottom of the ball is exposed from the circular hole and is in friction contact with the middle groove of the scraper conveyor.

[0014] As a further improvement of the present invention, a strain gauge is installed on each of the two side-by-side chain links installed on the same scraper, and each strain gauge is electrically connected to the two data processing modules on the same scraper at the same time.

[0015] As a further improvement of the present invention, the current running speed of the scraper chain is sensed by periodically monitoring the frequency of the piezoelectric vibrator power generation voltage, specifically:

[0016] Step S1, converting the simple sine wave voltage generated by the piezoelectric vibrator into a square wave voltage through the energy management module; Step S2, detecting the high and low pulse periods of the square wave voltage in a unit time, and obtaining the frequency of the force applied to the piezoelectric vibrator by calculation;

[0017] Step S3: Since the rotation speed of the turntable is related to the running speed of the scraper, and the excitation frequency of the force acting on the piezoelectric vibrator is related to the rotation speed of the turntable, the current running speed of the scraper is obtained by calculating the frequency of the piezoelectric vibrator power generation voltage.

[0018] In a third aspect, the present invention further proposes a method for monitoring the tension of a scraper chain, based on the tension monitoring system described above, comprising the following steps:

[0019] Step S1, taking all the tension monitoring nodes on the same side of the scraper as a node group, respectively recorded as node group N1 and node group N2; each node group is combined with one tension monitoring node at a time, and divided into two monitoring groups, and the two groups of node group N1 are recorded as group Z1 and group Z2;

[0020] Step S2: within the set operation cycle T of the scraper conveyor, the node group N1 monitors the tension data, and the node group N2 is in a dormant state;

[0021] Step S3, within the set operation cycle T of the scraper conveyor, the monitoring group Z1 collects the tension data of the strain gauges of the two scraper chain links on the same scraper without transmitting, and the monitoring group Z2 collects the tension data of the strain gauges of the two scraper chain links on the same scraper and transmits it wirelessly;

[0022] Step S4: In the set operation cycle T of the scraper conveyor, the working modes of the two monitoring groups are switched, that is, the monitoring group Z2 performs data collection without transmission, and the monitoring group Z1 performs data collection and wireless transmission; Step S5: In the set next operation cycle T of the scraper conveyor, the two node groups switch the working modes, that is, the node group N2 monitors the tension data, and the node group N1 is in a dormant state;

[0023] Step S6: Within N operation cycles T, the node group N1 and the node group N2 periodically monitor the tension data.

[0024] As a further improvement of the present invention, if the speed is monitored to be in the low speed range, it is determined that the current scraper conveyor is in a light load condition, and the data processor switches the tension data acquisition frequency of the strain gauge to a low sampling frequency mode; if the speed is monitored to be in the high speed range, it is determined that the current scraper conveyor is in a heavy load condition, and the data processor switches the tension data acquisition frequency of the strain gauge to a high sampling frequency mode.

[0025] As a further improvement of the present invention, all tension monitoring nodes on the scraper are numbered; when the convergence node receives abnormal tension data, the tension monitoring node is marked as a warning.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] (1) The energy harvesting device proposed in the present invention is constructed based on the technical principle of generating a periodic voltage signal by the non-contact piezoelectric effect. The energy harvesting is triggered by the movement of the scraper, and then a periodic voltage signal is obtained, which solves the problem of short life of the traditional wireless sensor nodes that rely on battery power supply, and is safe and reliable.

[0028] (2) The periodic voltage signal collected by the energy collection device of the present invention can be used for power supply of various loads on the one hand, and can be used for real-time perception of the scraper chain speed of the scraper conveyor on the other hand. That is, the present invention provides energy for the node while realizing automatic perception of the scraper chain speed of the scraper conveyor, thereby reflecting the operating condition of the scraper conveyor and adaptively adjusting the tension data sampling frequency, thereby ensuring the service quality of the scraper chain tension monitoring system;

[0029] (3) The tension monitoring system of the present invention realizes multi-point monitoring of the scraper chain by setting tension monitoring nodes at both ends of each scraper; and improves the tension monitoring quality of the scraper chain by realizing data exchange between the tension monitoring nodes and the convergence nodes;

[0030] (4) The monitoring method of the present invention can realize real-time monitoring of the normal / abnormal operation status of the scraper chain, and reduce the overall energy consumption of the monitoring network nodes under normal operation, thereby realizing the organic coordination of energy-saving monitoring and real-time monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Figure 1 It is a schematic diagram of the arrangement of the scraper chain tension monitoring system of the present invention;

[0033] Figure 2 It is the principle diagram of the scraper chain tension monitoring system of the present invention;

[0034] Figure 3 This is the installation process diagram of the tension monitoring node on the scraper;

[0035] Figure 4 Schematic diagram of the structure of the energy collection device in the tension monitoring node of the present invention I;

[0036] Figure 5 It is a structural schematic diagram II of the energy collection device in the tension monitoring node of the present invention;

[0037] Figure 6 It is a schematic diagram of the structure of a turntable of the energy collection device of the present invention;

[0038] Figure 7 It is a periodic voltage waveform diagram generated by the piezoelectric vibrator of the present invention;

[0039] Figure 8 It is a circuit diagram of an energy management module of a scraper chain tension monitoring node of the present invention;

[0040] Fig. 9 is a schematic diagram of energy management of the present invention;

[0041] Fig.10 is a circuit diagram of a data processing module of the present invention;

[0042] Fig.11 It is a process diagram of obtaining the running speed of the scraper chain of the present invention;

[0043] Fig.12 is a flow chart of the scraper chain tension monitoring method of the present invention;

[0044] In the figure: 1-substrate; 2-excited magnet; 3-main exciting magnet; 4-turntable; 5-passive roller; 6-bearing; 7-bearing seat; 8-piezoelectric vibrator; 9-beam; 10-bracket; 11-ball; 100-convergence node; 200-tension monitoring node; 300-scraper; 400-scraper chain; 500-hydraulic support. DETAILED DESCRIPTION

[0045] like Figure 1 As shown, the present invention proposes a scraper chain tension monitoring system, including a convergence node 100 and a tension monitoring node 200, wherein the tension monitoring node 200 is installed on the scraper 300 and the scraper chain 400, and the convergence node 100 is installed outside the scraper conveyor. In this embodiment, it is installed on the hydraulic support 500 of the underground working surface, and data communication is performed between the tension monitoring node 200 and the convergence node 100.

[0046] like Figure 2 The figure shows the working principle diagram of the tension monitoring system of the scraper chain. The tension monitoring node 200 includes an energy collection device, an energy management module, a data processing module, a wireless transmitter and receiver, and a strain gauge.

[0047] Please refer to Figure 3On the scraper conveyor, the scraper 300 is fixedly connected to two parallel scraper chains 400, and the scraper chains 400 are connected by chain links. The lower part of the scraper 300 is the middle groove on the scraper conveyor (not shown in the figure). Installation grooves are opened at both ends of each scraper 300, and each installation groove is installed with an energy collection device, an energy management module, a data processing module and a wireless transmitter and receiver. A strain gauge is installed on each chain link of the scraper chain 400 that cooperates with the scraper 300, namely the left chain strain gauge and the right chain strain gauge in the figure. The two strain gauges are electrically connected to the two data processors through cables, that is, each data processor is responsible for collecting the tension data on the chain links on the two scraper chains 400.

[0048] like Figure 4 As shown, the energy collection device includes two parts, an energy application unit and an energy contact unit, and the energy application unit and the energy receiving unit are installed on a substrate 1. Among them, the energy application unit includes a main excitation magnet 3, a turntable 4, a passive roller 5, a bearing seat 7 and a ball 11. The rotating shaft on the passive roller 5 is rotatably supported by two bearing seats 7. The turntable 4 is installed on one side of the rotating shaft and rotates with the rotating shaft. The bearing seat 7 is installed on the substrate 1. There are two main excitation magnets 3, which are symmetrically installed on the edge of the turntable 4. The passive roller 5 is an arc-shaped structure with the middle part retracted. A circular hole is opened on the substrate 1 directly below the passive roller 5, and the ball 11 is placed in the circular hole. The diameter of the circular hole is slightly larger than the diameter of the ball 11. The upper part of the ball 11 is in friction contact with the passive roller 5, and the lower part is placed in the middle groove and is in friction contact with the middle groove, as shown in FIG. Figure 5 As shown. The energy receiving unit includes an excited magnet 2, a piezoelectric vibrator 8, a beam 9 and a bracket 10. The bracket 10 is mounted on the substrate 1, one end of the beam 9 is fixedly connected to the bracket 10, the other end is mounted with the excited magnet 2, and the piezoelectric vibrator 8 is mounted in the middle. The excited magnet 2 is provided with an N pole and an S pole, and the excited magnet 2 is placed horizontally with its S pole facing outward. Please refer to Figure 6 , the main excitation magnet 3 is also provided with an N pole and an S pole, wherein the N pole faces outward. When the turntable 4 rotates, the excited magnet 2 and the main excitation magnet 3 have a closest distance to each other, i.e., a close distance. A slide groove is provided on the substrate 1, and the bracket 10 is installed on the slide groove. By adjusting the position of the bracket 10 on the slide groove, the close distance between the excited magnet 2 and the main excitation magnet 3 can be adjusted.

[0049] The working principle of the energy collection device is as follows: when the scraper 300 moves, the middle groove does not move. The ball 11 moves with the scraper 300, and the bottom thereof generates friction with the middle groove, which drives the ball 11 to rotate through the friction. The upper part of the ball 11 is in frictional contact with the passive roller 5, thereby driving the passive roller 5 to rotate, and the passive roller 5 drives the turntable 4 and the main excitation magnet 3 on the turntable 4 to rotate. When a main excitation magnet 3 approaches the excited magnet 2, a magnetic attraction is generated between the two. As the main excitation magnet 3 rotates upward, the magnetic attraction drives the excited magnet 3 upward, thereby driving the beam 9 to bend upward at a certain angle, driving the piezoelectric vibrator 8 to bend upward. When the first main excitation magnet 3 moves away from the excited magnet 2, the excited magnet 2 falls, and due to inertia, it moves downward, driving the piezoelectric vibrator 8 to bend downward. When the second main excitation magnet 3 rotates to the position of the excited magnet 2, its action is the same as that of the first main excitation magnet 3. As the turntable 4 rotates continuously, the piezoelectric vibrator 8 will vibrate up and down at a certain frequency, thereby generating a periodic voltage signal, such as Figure 7 shown.

[0050] Specifically, the upper and lower layers of the piezoelectric vibrator 8 are piezoelectric ceramics, and the middle layer is a copper substrate. The piezoelectric ceramics are bonded to the copper substrate by epoxy resin conductive adhesive.

[0051] In the tension monitoring node 200, the energy collection module is used to provide electrical energy to the energy management module, data processing module, strain gauge and wireless transmitter and receiver. The energy management module is used to process the voltage signal generated by the energy collection device, and to sense the current running speed of the scraper chain by periodically monitoring the frequency of the piezoelectric vibrator power generation voltage. Specifically, the energy management module uses the LTC3331 chip to rectify, filter, boost / step down the collected electrical signals. A lithium-ion battery is provided on the energy management module. When the energy collection device has surplus energy, the electrical energy is charged into the lithium-ion battery for standby use. Its structure is as follows: Figure 8 The energy transfer process of the energy management module is shown in Fig. 9 The data processing module is used to collect the tension monitoring data of the strain gauge. Specifically, the data processing module includes a data acquisition module and a data storage and transmission module. The data acquisition module collects the monitoring data of the strain gauge. The data storage and transmission module uses a CC2530 low-power module to transmit the monitoring data to the storage module of the CC2530 chip. Its structure is as follows Fig.10 The wireless transmitter and receiver are used to transmit the monitoring data acquired by the data processing module to the aggregation node. The wireless transmitter and receiver are transmitted to the aggregation node 100 via the ZigBee network. The aggregation node 100 is a controller, and the instructions sent by it are received and processed by the data processing module via the wireless transmitter and receiver.

[0052] Fig.11For the process diagram of obtaining the running speed of the scraper chain for the tension monitoring node, please refer to Figure 7 and Fig.11 , the specific process of obtaining the running speed of the scraper chain 400 is: using the comparator of the microprocessor in the data processing module to convert the simple sine wave voltage generated by the piezoelectric vibrator into a square wave voltage first; detecting the high and low pulse periods of the square wave voltage in a unit time; finally calculating the frequency of the excitation force on the piezoelectric vibrator; since the rotation speed of the rotating body is related to the running speed of the scraper, and the excitation frequency of the excitation force on the piezoelectric vibrator is related to the rotation speed of the rotating body, the frequency of the piezoelectric vibrator's generated voltage is calculated to obtain the current running speed of the scraper. Specifically, a part of the AC signal generated by the energy collection device enters the energy management module, which is mainly used to power the wireless transmitter and receiver and the CC2530 processor. The other part converts the generated AC signal into a square wave signal that can be detected by the CC2530 processor through signal pre-processing, that is, the frequency value f of the current AC signal is converted by detecting the period of high and low pulses in unit time, and its period value, that is, time, is obtained from the frequency f. Since two main exciting magnets 3 are arranged on the turntable 4, one rotation of the turntable will cause the excited magnet 2 or the piezoelectric vibrator to vibrate for two periods, thereby obtaining the time for the turntable 4 to rotate one circle. The rotation speed of the turntable 4 is the same as the rotation speed of the passive roller. The time required for the ball 11 to rotate one circle is obtained by the ratio of the circumference of the lowest point of the arc of the passive roller to the circumference of the ball 11. The speed is obtained from the time and its circumference, which is the same as the speed of the scraper 300. The speed of the scraper 300 is obtained, that is, the speed of the scraper chain 400 is obtained.

[0053] Please refer to Fig.12 The present invention also proposes a method for monitoring the tension of a scraper chain, comprising the following steps:

[0054] (1) All tension monitoring nodes on the same side of the scraper are regarded as a node group, which are respectively recorded as node group N1 and node group N2; each node group is divided into two monitoring groups according to the combination of tension monitoring nodes, and the two groups of node group N1 are recorded as group Z1 and group Z2.

[0055] (2) Within the set operation cycle T of the scraper conveyor, such as 2 hours or 4 hours, the node group N1 monitors the tension data and the node group N2 is in a dormant state; dormancy means that part of the hardware of the data processing module stops working.

[0056] (3) Within the set operation cycle T of the scraper conveyor, the monitoring group Z1 collects the tension data of the strain gauges of the two scraper chain links on the same scraper without transmitting it, and the monitoring group Z2 collects the tension data of the strain gauges of the two scraper chain links on the same scraper and transmits it wirelessly.

[0057] (4) Within the set operation cycle T of the scraper conveyor, the working modes of the two monitoring groups are switched, that is, the monitoring group Z2 performs data collection without transmission, and the monitoring group Z1 performs data collection and wireless transmission.

[0058] In step (3) and step (4), the operation cycle T is divided into two identical sub-cycles, for example, T is 4 hours and the sub-cycle is 2 hours. The first sub-cycle is executed according to step (3) and the second sub-cycle is executed according to step (4).

[0059] (5) In the next operation cycle T of the scraper conveyor, the two node groups switch working modes, that is, the node group N2 monitors the tension data, and the node group N1 is in a dormant state;

[0060] (6) Within N operating cycles T, node group N1 and node group N2 periodically monitor tension data.

[0061] Specifically, all tension monitoring nodes on the scraper are numbered, that is, the strain gauges are numbered, and the position of the tension monitoring node where it is located can be displayed regardless of normal tension data or abnormal tension data.

[0062] Since a data processing module is set at both ends of each scraper, a strain gauge is attached to the chain link of each scraper chain. The two strain gauges are connected to two data processing modules at the same time, that is, one data processing module can collect tension data of two scraper chains at the same time. The normal and abnormal tension data are determined by setting a data threshold range in the data processing module and comparing the data of the abnormal node and the surrounding nodes. If the tension data collected by the abnormal node and some of the surrounding nodes are above or below the threshold range, and abnormal conditions occur, the cause of the abnormality is the abnormality of the tension data of the scraper chain itself. The above may be a stuck chain fault, and the below may be a broken chain fault; conversely (the data of the surrounding nodes are normal), the cause of the abnormality may be a fault of the sensor itself. When a monitoring group Z2 on the same side collects and transmits tension data, if the data is abnormal, the abnormal data in the scraper chain it monitors is acquired by the convergence node 100, marked, and then sent to the host computer. At this time, Z1 only collects data but does not send data. If abnormal data appears in one of the nodes, the data of this node and some surrounding nodes will be sent to the aggregation node to determine whether the abnormal data is caused by a sensor failure or abnormal tension data of the scraper chain itself. Because the links of the scraper chain are interlocking, the abnormal tension data can be reflected in the links before and after it, that is, expressed by the tension data sent, and the scraper chain areas before and after it are marked.

[0063] In this method, whether the node group N2 on the other side is dormant or the monitoring group Z1 is not transmitting, it will not affect the monitoring of the scraper chain tension.

[0064] The monitoring method of the present invention, on the one hand, periodically monitors the running speed of the scraper chain. If the monitored speed is in the low speed range, it is determined that the current scraper conveyor is in a light load condition, and the data processor switches the tension data acquisition frequency of the strain gauge to a low sampling frequency mode; if the monitored speed is in the high speed range, it is determined that the current scraper conveyor is in a heavy load condition, and the data processor switches the tension data acquisition frequency of the strain gauge to a high sampling frequency mode. Thereby effectively improving the monitoring service quality of the scraper chain; on the other hand, the use of a cyclic monitoring method of the tension monitoring node can achieve the purpose of energy saving, so as to realize long-term monitoring of the scraper chain. Thirdly, the aggregation node uses the detected abnormal tension data to make a warning mark on the corresponding scraper chain area on the host computer to remind the staff to pay attention and handle it.

[0065] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited thereto. Various changes that can be made within the knowledge scope of technicians in the relevant technical field without departing from the spirit of the present invention are all within the protection scope of the claims of the present invention.

Claims

1. An energy collection device, characterized in that: include An energy application unit comprises a passive roller (5), a ball (11), a bearing seat (7), a turntable (4) and a main excitation magnet (3), wherein the rotating shaft on the passive roller (5) is supported by two bearing seats (7); the turntable (4) is mounted at one end of the rotating shaft; at least one main excitation magnet (3) is mounted on the edge of the turntable (4); the ball (11) is located below the passive roller (5), the upper part of which is in frictional contact with the bottom of the passive roller (5), and the bottom part receives the friction force to rotate, thereby driving the passive roller (5) to rotate, and then driving the main excitation magnet (3) on the turntable (4) to rotate; An energy receiving unit comprises a bracket (10), a beam (9), a piezoelectric vibrator (8) and an excited magnet (2), wherein one end of the beam (9) is fixedly connected to the bracket (10), the other end is mounted with the excited magnet (2), and the piezoelectric vibrator (8) is mounted in the middle; The main exciting magnet (3) rotates and generates a mutual force when it meets the excited magnet (2), causing the excited magnet (2) to vibrate up and down, driving the piezoelectric vibrator (8) to vibrate and generate a periodic voltage signal.

2. The energy collection device according to claim 1, characterized in that: There are two main exciting magnets (3), which are located at two ends of the diameter of the rotating disk (4).

3. The energy collection device according to claim 1, characterized in that: The main exciting magnet (3) and the excited magnet (2) generate mutual attraction.

4. A scraper chain tension monitoring system, characterized in that: It comprises a convergence node (100) and a tension monitoring node (200), wherein the tension monitoring node (200) is installed on a scraper (300); the tension monitoring node (200) comprises an energy collection device, an energy management module, a data processing module, a strain gauge and a wireless transmitter and receiver according to any one of claims 1 to 3; the energy collection device, the energy management module, the data processing module and the wireless transmitter and receiver are installed at both ends of each scraper (200), and the strain gauge is installed on a scraper chain (400); The energy management module is used to process the voltage signal generated by the energy collection device, and is used to sense the current running speed of the scraper chain (400) by periodically monitoring the frequency of the generated voltage of the piezoelectric vibrator (8); The data processing module is used to collect the tension monitoring data of the strain gauge; The wireless transmitter and receiver is used to transmit the tension monitoring data acquired by the data processing module to the aggregation node (100).

5. The scraper chain tension monitoring system according to claim 4, characterized in that: The bracket (10) on the energy collection device is installed on a substrate (1), and a circular hole is opened at the substrate (1) directly below the ball, and the bottom of the ball is exposed from the circular hole and is in friction contact with the middle groove of the scraper conveyor.

6. The scraper chain tension monitoring system according to claim 4, characterized in that: A strain gauge is installed on each of the two side-by-side chain links installed on the same scraper (300), and each strain gauge is electrically connected to the two data processing modules on the same scraper (300) at the same time.

7. The scraper chain tension monitoring system according to claim 4, characterized in that: The current running speed of the scraper chain is sensed by periodically monitoring the frequency of the piezoelectric vibrator power generation voltage, specifically: Step S1, converting the simple sine wave voltage generated by the piezoelectric vibrator (8) into a square wave voltage through the energy management module; Step S2, detecting the high and low pulse periods of the square wave voltage within a unit time, and obtaining the frequency of the force applied to the piezoelectric vibrator (8) by calculation; Step S3: Since the rotation speed of the turntable (4) is related to the running speed of the scraper (300), and the excitation frequency of the force acting on the piezoelectric vibrator (8) is related to the rotation speed of the turntable, the current running speed of the scraper (300) is obtained by calculating the frequency of the generated voltage of the piezoelectric vibrator (8).

8. A method for monitoring the tension of a scraper chain, based on the tension monitoring system according to any one of claims 4 to 7, characterized in that: The following steps are involved: Step S1, treating all tension monitoring nodes on the same side of the scraper (300) as a node group, respectively denoted as node group N1 and node group N2; each node group is combined with one tension monitoring node in between, and is divided into two monitoring groups, and the two groups of node group N1 are denoted as group Z1 and group Z2; Step S2: within the set operation cycle T of the scraper conveyor, the node group N1 monitors the tension data, and the node group N2 is in a dormant state; Step S3, within the set operation cycle T of the scraper conveyor, the monitoring group Z1 collects the tension data of the strain gauges of the two scraper chain links on the same scraper without transmitting, and the monitoring group Z2 collects the tension data of the strain gauges of the two scraper chain links on the same scraper and transmits it wirelessly; Step S4, within the set operation cycle T of the scraper conveyor, the working modes of the two monitoring groups are switched, that is, the monitoring group Z2 performs data collection without transmission, and the monitoring group Z1 performs data collection and wireless transmission; Step S5: In the next operation cycle T of the scraper conveyor, the two node groups switch working modes, that is, the node group N2 monitors the tension data, and the node group N1 is in a dormant state; Step S6: Within N operation cycles T, the node group N1 and the node group N2 periodically monitor the tension data.

9. The method for monitoring the tension of a scraper chain according to claim 8, characterized in that: If the speed is monitored to be in the low speed range, the current scraper conveyor is determined to be in a light load condition, and the data processor switches the strain gauge tension data acquisition frequency to a low sampling frequency mode; if the speed is monitored to be in the high speed range, the current scraper conveyor is determined to be in a heavy load condition, and the data processor switches the strain gauge tension data acquisition frequency to a high sampling frequency mode.

10. The method for monitoring the tension of a scraper chain according to claim 8, characterized in that: All tension monitoring nodes on the scraper are numbered; when the aggregation node receives abnormal tension data, the tension monitoring node is marked as a warning.

Images