Wind speed sensor for coal mine

Abstract

The invention discloses a wind speed sensor for a coal mine, and relates to the technical field of sensors for coal mines. The wind speed sensor for the coal mine has a wind direction function, can timely and accurately reflect the real underground state under the condition that the wind speed changes rapidly and is unstable, solves the problem of high-frequency interference through the pitot tube principle and algorithm, and utilizes various signal output modules to realize the real-time monitoring of the coal mine. According to the utility model, the integration of current type, frequency type and RS485 bus type output multi-system communication modes is realized, the requirements of different systems of the current coal mine safety monitoring system are met, and the problem of transmission signal interruption caused by frequent wall deviation and roof fall of a mine is solved through the combination of wired and wireless functions; the problem that the wind measurement inlet and outlet of the sensor element are blocked and cannot be accurately measured is solved through a mechanical structure.

Description

Technical Field

[0001] The invention belongs to the technical field of coal mine sensors, and in particular relates to a wind speed sensor for coal mines. Background Art

[0002] At present, my country's coal mine safety monitoring system has made great progress, but there are still some urgent problems in the existing coal mine safety monitoring system, especially in the information collection and transmission technology of the coal mine safety monitoring system, which is restricted by false alarms, backward collection methods, low intelligence, heavy maintenance workload and personnel misoperation, which seriously affects the reliability of the coal mine safety monitoring system. In particular, the existing wind speed sensor for coal mines has no wind direction function, imperfect functions and low accuracy, and cannot be used for intelligent ventilation and leakage detection.

[0003] With the development of coal mine safety production, the market demand for high-precision wind speed sensors has gradually increased, but there are currently no products that meet the requirements. At present, the domestic market generally adopts wind speed sensors designed based on the vortex street principle and the differential pressure principle. Due to the design principle and mechanical structure, the sensor has poor stability and is inconvenient to install. Although coal mine users have many complaints, they can only accept existing products because there are no better products. At the same time, the wind speed sensor using the vortex street principle is easily affected by the high-frequency interference of large underground equipment and does not take into account the hidden dangers of cable damage caused by frequent deviation and roof collapse in the mine, which may interrupt the transmission signal. The wind speed sensor designed based on the differential pressure principle, due to the harsh underground environment, high dust and stickiness, it is easy to block the wind measurement entrance and exit of the sensor element and cannot accurately measure. The wind speed changes quickly and is unstable, making it difficult to accurately reflect the real state of the underground in a timely manner. It is easy to cause cable damage, resulting in the problem of signal transmission failure. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a wind speed sensor for coal mines, which solves the problems of the existing wind speed sensors having no wind direction function, poor stability, inconvenient installation, cable damage resulting in interruption of transmission signals, high-frequency interference, and blockage of wind measurement entrances and exits that make accurate measurements impossible.

[0005] The technical solution of the present invention is:

[0006] A wind speed sensor for coal mines comprises a wind speed detection circuit housing, a cable, a wind speed detection circuit, a first nut, a second nut, two metal pipes, a metal pipe fixing structure, a lower air chamber leak-proof fixing nut kit, a sensor probe housing, a detachable gasket, an ultrasonic probe cable interface, two ultrasonic transmitting probes, two ultrasonic receiving probes and a three-way connection structure;

[0007] The wind speed detection circuit housing is used to protect the wind speed detection circuit installed inside it;

[0008] The first nut is used to connect the metal pipe fixing structure with the three-way connection structure;

[0009] The metal tube fixing structure is provided with two holes, and two metal tubes pass through the holes respectively and are vertically fixed on the metal tube fixing structure through nuts, wherein the two metal tubes are a long metal tube and a short metal tube;

[0010] The second nut is used to connect the metal pipe fixing structure to the sensor probe housing;

[0011] A partition is arranged inside the housing of the sensor probe to divide its internal space into two parts, namely an upper air chamber and a lower air chamber. The lower end of the long metal tube extends into the lower air chamber through an opening on the partition, and the long metal tube is fixed to the partition by a leak-proof fixing nut kit of the lower air chamber, while ensuring the sealing between the upper air chamber and the lower air chamber, and the lower end of the short metal tube is placed in the upper air chamber. A large through hole is arranged on one side of the housing of the sensor probe, and a small through hole is arranged on the other side. The large through hole is located in the lower air chamber, and the small through hole is located in the upper air chamber. When measuring, the large through hole is placed windward and the small through hole is placed leeward.

[0012] The three-way connection structure is located below the wind speed detection circuit housing, the left port of the three-way connection structure is the ultrasonic probe cable interface, the right port of the three-way connection structure is used to place the cable, and the upper ports of the long metal tube and the short metal tube are connected to the wind speed detection circuit in the lower port of the three-way connection structure;

[0013] The two ultrasonic transmitting probes are used to transmit ultrasonic waves to the ultrasonic receiving probe;

[0014] The two ultrasonic receiving probes are used to receive the ultrasonic waves emitted by the ultrasonic transmitting probe and convert them into electrical signals;

[0015] The wind speed detection circuit obtains the total pressure and static pressure from the upper ports of the long metal tube and the short metal tube respectively, and obtains the wind speed measurement result according to the pressure difference between the total pressure and the static pressure, and simultaneously receives the electrical signals collected by the two ultrasonic receiving probes, determines the wind direction according to the vortex street principle and obtains the wind speed measurement result, and the obtained wind speed measurement result is transmitted to the substation switch and the host computer through the cable;

[0016] The cable is connected to the substation switch and the host computer through a port of the three-way connection structure, and is used to transmit the wind speed measurement result of the wind speed detection circuit to the substation switch and the host computer;

[0017] Furthermore, the wind speed sensor for coal mines further comprises a handle, which is mounted on the wind speed detection circuit housing to facilitate the worker to take it;

[0018] Furthermore, the wind speed sensor for coal mines further comprises a detachable gasket, which is fixed to the bottom of the sensor probe housing by means of threads and is used for cleaning coal dust after disassembly;

[0019] Furthermore, the two ultrasonic transmitting probes are respectively a first ultrasonic transmitting probe and a second ultrasonic transmitting probe, and the two ultrasonic receiving probes are respectively a first ultrasonic receiving probe and a second ultrasonic receiving probe, the first ultrasonic transmitting probe is arranged opposite to the first ultrasonic receiving probe, and the second ultrasonic transmitting probe is also arranged opposite to the second ultrasonic receiving probe, and the two sets of ultrasonic transmitting probes and ultrasonic receiving probes are placed perpendicular to the wind flow direction in the test area;

[0020] Further, the wind speed detection circuit includes an intrinsically safe power supply, a power conversion and protection module, a pressure sensor, a signal processing module, a CPU data processing control center module, an infrared remote control module, a data display and remote control signal processing module, a display module, a variety of signal output modules and a wireless module;

[0021] The intrinsically safe power supply is electrically connected to the power conversion and protection module for supplying power;

[0022] The power conversion and protection module is used to convert the voltage provided by the intrinsically safe power supply, provide an adaptive voltage for the pressure sensor, the signal processing module, the CPU data processing control center module, the data display and remote control signal processing module, the display module, the multiple signal output module, the two ultrasonic transmitting probes, the two ultrasonic receiving probes and the wireless module, and isolate the above modules from the intrinsically safe power supply to protect the circuit;

[0023] The pressure sensor is connected to two metal tubes, and uses the Pitot tube principle to obtain the total pressure and static pressure from the upper ports of the long metal tube and the short metal tube respectively and sends them to the CPU data processing control center module;

[0024] The signal processing module is used to amplify and filter the electrical signals collected by the two ultrasonic receiving probes, and send the processed electrical signals to the CPU data processing control center module;

[0025] The infrared remote control module is used to send remote control signals and set the signal output types of the various signal output modules;

[0026] The data display and remote control signal processing module is used to receive the remote control signal and forward it to the CPU data processing control center module; receive the wind speed measurement result calculated by the CPU data processing control center module, convert it into the level required by the display module, and send it to the display module;

[0027] After receiving the remote control signal, the CPU data processing control center module performs self-diagnosis on the output circuit of the signal output type in the multiple signal output modules according to the set signal output type, and determines whether there is a fault. When there is a fault, the wireless module is enabled, otherwise the multiple signal output modules are used; then the pressure difference is calculated according to the received total pressure and static pressure, and the wind speed measurement result is calculated according to the differential pressure principle; the wind direction is determined according to the vortex street principle and the electrical signals collected by the two ultrasonic receiving probes, and the wind speed measurement result is calculated; the wind speed measurement result calculated according to the differential pressure principle and the wind speed measurement result calculated according to the vortex street principle are compared, and when the difference is within the error range, it is determined to be working normally, and then it is further determined whether the current wind speed measurement result is greater than the set threshold value. If so, the wind speed measurement result calculated according to the vortex street principle is taken and sent to the data display and remote control signal processing module, otherwise the wind speed measurement result calculated according to the differential pressure principle is taken and sent to the data display and remote control signal processing module, and sent to the wireless module or the multiple signal output modules at the same time;

[0028] The display module is used to display the wind speed measurement result;

[0029] The various signal output modules are used to transmit wind speed measurement results to the substation switch and the host computer through current output, frequency output and RS485 bus output;

[0030] The wireless module is electrically connected to the CPU data processing control center module and is used to wirelessly transmit the wind speed measurement results to the wireless substation switch and the host computer;

[0031] Furthermore, the method for determining the wind direction based on the vortex street principle and the electrical signals collected by the two ultrasonic receiving probes is as follows:

[0032] A generating rod is set in the middle position of two groups of ultrasonic transmitting probes and ultrasonic receiving probes placed opposite each other. When the wind direction is from the first ultrasonic transmitting probe and the first ultrasonic receiving probe to the second ultrasonic transmitting probe and the second ultrasonic receiving probe, the ultrasonic wave received by the second ultrasonic receiving probe will be affected by the vortex generated by the wind passing through the generating rod, and the collected electrical signal will be larger. When the wind direction is from the second ultrasonic transmitting probe and the second ultrasonic receiving probe to the first ultrasonic transmitting probe and the first ultrasonic receiving probe, the ultrasonic wave received by the first ultrasonic receiving probe will be affected by the vortex generated by the wind passing through the generating rod, and the collected electrical signal will be larger. The wind direction is then judged by the size of the electrical signals collected by the two ultrasonic receiving probes.

[0033] Compared with the prior art, the beneficial effects of the present invention are:

[0034] The coal mine wind speed sensor of the present invention has a wind direction function, and can timely and accurately reflect the actual state of the mine when the wind speed changes rapidly and is unstable. The high-frequency interference problem is solved by the Pitot tube principle and algorithm, and a variety of signal output modules are used to realize the integration of current-type, frequency-type and RS485 bus-type output multi-standard communication modes, meeting the needs of different standards of the current coal mine safety monitoring system. At the same time, the wired and wireless functions are combined to solve the problem of transmission signal interruption caused by frequent mine deviation and roof collapse, and the mechanical structure is used to solve the problem that the wind measurement entrance and exit of the sensor element are blocked and cannot be accurately measured. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a structural diagram of the coal mine wind speed sensor according to an embodiment of the present invention;

[0036] Figure 2 is a cross-sectional view of a metal pipe fixing structure in an embodiment of the present invention;

[0037] Figure 3 A top view of a metal pipe fixing structure in an embodiment of the present invention;

[0038] Figure 4 is a cross-sectional view of a short metal tube in an embodiment of the present invention;

[0039] Figure 5 is a cross-sectional view of a long metal tube in an embodiment of the present invention;

[0040] Figure 6 It is a structural schematic diagram of the lower air chamber leak-proof fixing nut kit in an embodiment of the present invention;

[0041] Figure 7 is a schematic diagram of a detachable gasket in an embodiment of the present invention;

[0042] Figure 8 is a structural diagram of a wind speed detection circuit in an embodiment of the present invention;

[0043] Fig. 9 is a circuit diagram of a power conversion and protection module in an embodiment of the present invention;

[0044] Fig.10 is a circuit diagram of a signal processing module in an embodiment of the present invention;

[0045] Fig.11 The circuit diagram of the CPU data processing control center module in the embodiment of the present invention;

[0046] Fig.12 Schematic diagram of the principle of determining wind direction in an embodiment of the present invention;

[0047] Fig.13 is a circuit diagram of a display module in an embodiment of the present invention;

[0048] Fig.14 is a circuit diagram of various signal output modules in an embodiment of the present invention;

[0049] Among them, 1-handle; 2-wind speed detection circuit housing; 3-cable; 4-first nut; 5-second nut; 6-sensor probe housing; 7-detachable gasket; 8-ultrasonic probe cable interface; 9-three-way connection structure; 10-metal pipe fixing structure. DETAILED DESCRIPTION

[0050] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0051] like Figure 1 As shown, a wind speed sensor for coal mines includes a handle 1, a wind speed detection circuit housing 2, a cable 3, a wind speed detection circuit, a first nut 4, a second nut 5, two metal tubes, a metal tube fixing structure 10, a lower air chamber leak-proof fixing nut kit, a sensor probe housing 6, a detachable gasket 7, an ultrasonic probe cable interface 8, two ultrasonic transmitting probes, two ultrasonic receiving probes and a three-way connection structure 9;

[0052] The handle 1 is installed on the wind speed detection circuit housing 2 to facilitate the staff to take it;

[0053] The wind speed detection circuit housing 2 is used to protect the wind speed detection circuit installed therein;

[0054] The first nut 4 uses the external thread provided on the upper end of the metal pipe fixing structure 10 to connect the metal pipe fixing structure 10 with the three-way connection structure 9;

[0055] like Figure 2 and Figure 3 As shown, two holes are opened on the metal tube fixing structure 10, and two metal tubes pass through the holes respectively and are vertically fixed on the metal tube fixing structure 10 by nuts. Figure 4-Figure 5 As shown, the two metal tubes are a long metal tube and a short metal tube;

[0056] The second nut 5 connects the metal tube fixing structure 10 to the sensor probe housing 6 by using the external thread provided at the lower end of the metal tube fixing structure 10;

[0057] The sensor probe housing 6 is provided with a partition plate to divide its internal space into two parts, namely an upper air chamber and a lower air chamber. The lower end of the long metal tube extends into the lower air chamber through the opening on the partition plate and passes through the Figure 6The lower air chamber leak-proof fixing nut kit shown fixes the long metal tube on the partition, and ensures the sealing between the upper air chamber and the lower air chamber, while the lower end of the short metal tube is placed in the upper air chamber, and a large through hole is set on one side of the sensor probe housing 6, and a small through hole is set on the other side, and the large through hole is located in the lower air chamber, and the small through hole is located in the upper air chamber. When measuring, the large through hole is placed windward and the small through hole is placed leeward;

[0058] like Figure 7 As shown, the removable gasket 7 is fixed to the bottom of the sensor probe housing 6 by means of threads, and is used to clean the coal ash after disassembly to avoid clogging;

[0059] The three-way connection structure 9 is located below the wind speed detection circuit housing 2, the left port of the three-way connection structure 9 is the ultrasonic probe cable interface 8, the right port of the three-way connection structure 9 is used to place the cable 3, and the upper ports of the long metal tube and the short metal tube are connected to the wind speed detection circuit in the lower port of the three-way connection structure 9;

[0060] The two ultrasonic transmitting probes are used to transmit ultrasonic waves to the ultrasonic receiving probe;

[0061] The two ultrasonic receiving probes are used to receive the ultrasonic waves emitted by the ultrasonic transmitting probe and convert them into electrical signals;

[0062] The two ultrasonic transmitting probes are respectively a first ultrasonic transmitting probe and a second ultrasonic transmitting probe, and the two ultrasonic receiving probes are respectively a first ultrasonic receiving probe and a second ultrasonic receiving probe, the first ultrasonic transmitting probe is arranged opposite to the first ultrasonic receiving probe, and the second ultrasonic transmitting probe is also arranged opposite to the second ultrasonic receiving probe, and the two sets of ultrasonic transmitting probes and ultrasonic receiving probes are placed perpendicular to the wind flow direction in the test area;

[0063] The wind speed detection circuit obtains the total pressure and static pressure from the upper ports of the long metal tube and the short metal tube respectively, and obtains the wind speed measurement result according to the pressure difference between the total pressure and the static pressure, and simultaneously receives the electrical signals collected by the two ultrasonic receiving probes, determines the wind direction according to the vortex street principle and obtains the wind speed measurement result, and the obtained wind speed measurement result is transmitted to the substation switch and the host computer through the cable 3, and the two wind speed measurement methods are combined to increase the accuracy of the wind speed measurement result;

[0064] The cable 3 is connected to the substation switch and the host computer through a port of the three-way connection structure 9, and is used to transmit the wind speed measurement result of the wind speed detection circuit to the substation switch and the host computer, so as to facilitate the operators on the ground to view and analyze;

[0065] like Figure 8As shown, the wind speed detection circuit includes an intrinsically safe power supply, a power conversion and protection module, a pressure sensor, a signal processing module, a CPU data processing control center module, an infrared remote control module, a data display and remote control signal processing module, a display module, a variety of signal output modules and a wireless module;

[0066] The intrinsically safe power supply is electrically connected to the power conversion and protection module for supplying power;

[0067] like Fig. 9 As shown, the power conversion and protection module is used to convert the voltage provided by the intrinsically safe power supply, provide an adaptive voltage for the pressure sensor, signal processing module, CPU data processing control center module, data display and remote control signal processing module, display module, multiple signal output module, two ultrasonic transmitting probes, two ultrasonic receiving probes and wireless module, and isolate the above modules from the intrinsically safe power supply to protect the circuit;

[0068] In this embodiment, the power conversion and protection module includes a three-terminal voltage regulator 78L06 and its peripheral circuits, a three-terminal voltage regulator MCP1541 and its peripheral circuits, a switching regulator LM5008A and its peripheral circuits, and a voltage management voltage regulator chip HT7550 and its peripheral circuits;

[0069] Pin 1 of the three-terminal voltage regulator 78L06 is connected to 21V, pin 2 is grounded, pin 3 outputs a +6V voltage, pin 1 is connected to pin 2 via a capacitor C30, two capacitors C31 and C32 are connected in parallel between pin 3 and pin 2, and two diodes D6 and D7 are connected in parallel;

[0070] Pin 1 of the three-terminal voltage regulator MCP1541 is connected to 5V, pin 3 is grounded, pin 2 outputs a 4.1V voltage, pin 1 is connected to pin 3 via a capacitor C56, and two capacitors C54 and C55 are connected in parallel between pin 3 and pin 2;

[0071] The 8th pin of the switching regulator LM5008A is connected to the input voltage, the 6th pin is connected to the input voltage through a resistor R301, the 4th pin is grounded, and the 3rd pin is grounded through a resistor R302. A capacitor C301 is set between the input voltage and the ground; a capacitor C302 is set between the 2nd pin and the 1st pin, the 7th pin is grounded through a capacitor C303, a diode is set between the 1st pin and the 7th pin, and the 1st pin is connected to an inductor L301 and a sliding rheostat in sequence and then grounded, one end of the capacitor C304 is connected to the 5th pin, and the other end is connected to a fixed end of the sliding rheostat, and a capacitor C305 and two diodes D302 and D303 are connected in parallel between the output +5V voltage and the ground;

[0072] Pin 1 of the voltage management and voltage stabilizing chip HT7550 is connected to a 5.3V voltage, pin 2 is grounded, and pin 3 outputs +5V. A capacitor C28 is set between pin 1 and the ground, a capacitor C29 is set between +5V and the ground, and two voltage-dividing resistors R58 and R59 are set between pin 1 and the ground. The voltage between the two resistors is connected to pin 9 of the PIC18F4520 in the CPU data processing control center module.

[0073] The pressure sensor is connected to two metal tubes, and uses the Pitot tube principle to obtain the total pressure and static pressure from the upper ports of the long metal tube and the short metal tube respectively and sends them to the CPU data processing control center module;

[0074] The signal processing module is used to amplify and filter the electrical signals collected by the two ultrasonic receiving probes, and send the processed electrical signals to the CPU data processing control center module;

[0075] The signal processing module in this embodiment is as follows: Fig.10As shown, it includes two identical branches. Taking one of the branches as an example, the ultrasonic receiving probe P2 is connected in parallel with a resistor R203, one end of the resistor R203 is grounded, and the other end is connected to the fixed end of the sliding rheostat through a capacitor C203, and the other fixed end of the sliding rheostat is connected to the 6th pin of the operational amplifier LM833, the 3rd pin of the operational amplifier LM833 is connected to the 5V voltage, the 4th pin is grounded, and a capacitor C204 is set between 5V and the ground, the 5th pin of the operational amplifier LM833 is connected to A2.5V through a resistor R207, a capacitor C51 and a resistor R205 are connected in parallel between the 7th pin and the 6th pin, and the resistor One end of R206 is connected to pin 7 and the other end is grounded. At the same time, pin 7 is connected to pin 2 through capacitor C205 and resistor R209. Pin 3 is connected to A2.5V through resistor R208. Pin 2 is connected to pin 1 through resistor R210. At the same time, a grounding resistor R211 is set at pin 1. One end of capacitor C206 is connected to pin 1 and the other end is connected to a grounding resistor R212 and a diode D201. Then diode D201 is connected to capacitor C208, resistor R214 and connected to pin 2 of operational amplifier MCP6002 in sequence; pin 3 connected to operational amplifier MCP6002 is connected through resistor R21 7 is connected to B2.5V, 8 is connected to 5V voltage, 4 is grounded, and a capacitor C214 is set between 5V and ground. Resistor R215 and capacitor C210 are connected in parallel between pins 1 and 2. At the same time, pin 1 is connected to a grounding resistor R216 and capacitor C211, resistor R219. The circuit connection of pins 5, 6 and 7 of the operational amplifier LM833 is similar to that of pins 1, 2 and 3. The non-grounded pin of the grounding resistor connected to pin 7 is connected to one end of resistor R224. One end of resistor R224 is connected to pins 2 and 6 of the operational amplifier LM2903 respectively, and is grounded through capacitor C215. The 3rd, 5th and 8th pins of the LM2903 are connected to 5V, the 4th pin is grounded, and a capacitor C216 is set between 5V and the ground. One end of the resistor R229 is connected to the 5th pin and the other end is respectively connected to the 7th pin and one end of the resistor R230. The other end of the resistor R230 is connected to 5V. The 7th pin is connected to the CPU data processing control center module through a resistor R231. One end of the resistor R227 is connected to the 3rd pin, and the other end is connected to the 1st pin and the resistor R228. The other end of the resistor R228 is connected to 5V through a diode. The infrared remote control module is used to send remote control signals and set the signal output type of multiple signal output modules.

[0076] The data display and remote control signal processing module is used to receive the remote control signal and forward it to the CPU data processing control center module; receive the wind speed measurement result calculated by the CPU data processing control center module, convert it into the level required by the display module, and send it to the display module;

[0077] like Fig.11 As shown, after receiving the remote control signal, the CPU data processing control center module performs self-diagnosis on the output circuit of the signal output type in the multiple signal output modules according to the set signal output type to determine whether there is a fault. When there is a fault, the wireless module is enabled, otherwise multiple signal output modules are used; then the sensor program is initialized and calibrated. If it cannot be calibrated or adjusted, it is considered damaged; then the pressure difference is calculated according to the received total pressure and static pressure, and the wind speed measurement result is calculated according to the differential pressure principle; according to the vortex street principle and the electrical signals collected by the two ultrasonic receiving probes, the wind direction is determined, and the wind speed measurement result is calculated; the wind speed measurement result calculated according to the differential pressure principle is compared with the wind speed measurement result calculated according to the vortex street principle. When the difference is within the error range, it is determined to be working normally, and then it is further determined whether the current wind speed measurement result is greater than the set threshold. If so, the wind speed measurement result calculated according to the vortex street principle is taken and sent to the data display and remote control signal processing module, otherwise the wind speed measurement result calculated according to the differential pressure principle is taken and sent to the data display and remote control signal processing module, and sent to the wireless module or multiple signal output modules at the same time;

[0078] The method for determining the wind direction based on the vortex street principle and the electrical signals collected by two ultrasonic receiving probes is as follows:

[0079] like Fig.12 As shown, a generating rod is arranged in the middle of two groups of ultrasonic transmitting probes and ultrasonic receiving probes placed opposite to each other. When the wind direction is from the first ultrasonic transmitting probe and the first ultrasonic receiving probe to the second ultrasonic transmitting probe and the second ultrasonic receiving probe, the ultrasonic wave received by the second ultrasonic receiving probe will be affected by the vortex generated by the wind passing through the generating rod, and the collected electrical signal will be larger. When the wind direction is from the second ultrasonic transmitting probe and the second ultrasonic receiving probe to the first ultrasonic transmitting probe and the first ultrasonic receiving probe, the ultrasonic wave received by the first ultrasonic receiving probe will be affected by the vortex generated by the wind passing through the generating rod, and the collected electrical signal will be larger. Then, the wind direction is determined by the size of the electrical signals collected by the two ultrasonic receiving probes.

[0080] like Fig.13 As shown, the display module is used to display the wind speed measurement results for analysis and reference by underground workers;

[0081] like Fig.14 As shown, the various signal output modules are used to transmit wind speed measurement results to the substation switch and the host computer through current output, frequency output and RS485 bus output;

[0082] The wireless module is electrically connected to the CPU data processing control center module and is used to wirelessly transmit the wind speed measurement results to the wireless substation switch and the host computer;

[0083] The chip used for wireless data transmission in this embodiment is the NRF24L01 chip produced by Nordic Semiconductor, which uses the 2.4 GHz globally open ISM frequency band.

Claims

1. A wind speed sensor for coal mines, characterized in that: It includes a wind speed detection circuit housing, a cable, a wind speed detection circuit, a first nut, a second nut, two metal tubes, a metal tube fixing structure, a lower air chamber leak-proof fixing nut kit, a sensor probe housing, a detachable gasket, an ultrasonic probe cable interface, two ultrasonic transmitting probes, two ultrasonic receiving probes and a three-way connection structure; The wind speed detection circuit housing is used to protect the wind speed detection circuit installed inside it; The first nut is used to connect the metal pipe fixing structure with the three-way connection structure; The metal tube fixing structure is provided with two holes, and two metal tubes pass through the holes respectively and are vertically fixed on the metal tube fixing structure through nuts, wherein the two metal tubes are a long metal tube and a short metal tube; The second nut is used to connect the metal pipe fixing structure to the sensor probe housing; A partition is arranged inside the housing of the sensor probe to divide its internal space into two parts, namely an upper air chamber and a lower air chamber. The lower end of the long metal tube extends into the lower air chamber through an opening on the partition, and the long metal tube is fixed to the partition by a leak-proof fixing nut kit of the lower air chamber, while ensuring the sealing between the upper air chamber and the lower air chamber, and the lower end of the short metal tube is placed in the upper air chamber. A large through hole is arranged on one side of the housing of the sensor probe, and a small through hole is arranged on the other side. The large through hole is located in the lower air chamber, and the small through hole is located in the upper air chamber. When measuring, the large through hole is placed windward and the small through hole is placed leeward. The removable gasket is fixed to the bottom of the sensor probe housing by means of threads and is used for cleaning coal dust after disassembly; The three-way connection structure is located below the wind speed detection circuit housing, the left port of the three-way connection structure is the ultrasonic probe cable interface, the right port of the three-way connection structure is used to place the cable, and the upper ports of the long metal tube and the short metal tube are connected to the wind speed detection circuit in the lower port of the three-way connection structure; The two ultrasonic transmitting probes are used to transmit ultrasonic waves to the ultrasonic receiving probe; The two ultrasonic receiving probes are used to receive the ultrasonic waves emitted by the ultrasonic transmitting probe and convert them into electrical signals; The wind speed detection circuit obtains the total pressure and static pressure from the upper ports of the long metal tube and the short metal tube respectively, and obtains the wind speed measurement result according to the pressure difference between the total pressure and the static pressure, and simultaneously receives the electrical signals collected by the two ultrasonic receiving probes, determines the wind direction according to the vortex street principle and obtains the wind speed measurement result, and the obtained wind speed measurement result is transmitted to the substation switch and the host computer through the cable; The cable is connected to the substation switch and the host computer through a port of the three-way connection structure, and is used to transmit the wind speed measurement result of the wind speed detection circuit to the substation switch and the host computer.

2. The wind speed sensor for coal mine according to claim 1, characterized in that: The wind speed detection circuit also includes a handle, which is installed on the wind speed detection circuit housing to facilitate staff to take it.

3. The wind speed sensor for coal mine according to claim 1 or 2, characterized in that: The utility model also comprises a detachable gasket, which is fixed to the bottom of the housing of the sensor probe by means of threads and is used for cleaning coal dust after disassembly.

4. The wind speed sensor for coal mine according to claim 3, characterized in that: The two ultrasonic transmitting probes are respectively the first ultrasonic transmitting probe and the second ultrasonic transmitting probe, and the two ultrasonic receiving probes are respectively the first ultrasonic receiving probe and the second ultrasonic receiving probe. The first ultrasonic transmitting probe is arranged opposite to the first ultrasonic receiving probe, and the second ultrasonic transmitting probe is also arranged opposite to the second ultrasonic receiving probe. The two sets of ultrasonic transmitting probes and ultrasonic receiving probes are placed in the test area perpendicular to the wind flow direction.

5. The wind speed sensor for coal mine according to claim 4, characterized in that: The wind speed detection circuit includes an intrinsically safe power supply, a power conversion and protection module, a pressure sensor, a signal processing module, a CPU data processing control center module, an infrared remote control module, a data display and remote control signal processing module, a display module, a variety of signal output modules and a wireless module; The intrinsically safe power supply is electrically connected to the power conversion and protection module for supplying power; The power conversion and protection module is used to convert the voltage provided by the intrinsically safe power supply, provide an adaptive voltage for the pressure sensor, the signal processing module, the CPU data processing control center module, the data display and remote control signal processing module, the display module, the multiple signal output module, the two ultrasonic transmitting probes, the two ultrasonic receiving probes and the wireless module, and isolate the above modules from the intrinsically safe power supply to protect the circuit; The pressure sensor is connected to two metal tubes, and uses the Pitot tube principle to obtain the total pressure and static pressure from the upper ports of the long metal tube and the short metal tube respectively and sends them to the CPU data processing control center module; The signal processing module is used to amplify and filter the electrical signals collected by the two ultrasonic receiving probes, and send the processed electrical signals to the CPU data processing control center module; The infrared remote control module is used to send remote control signals and set the signal output types of the various signal output modules; The data display and remote control signal processing module is used to receive the remote control signal and forward it to the CPU data processing control center module; receive the wind speed measurement result calculated by the CPU data processing control center module, convert it into the level required by the display module, and send it to the display module; After receiving the remote control signal, the CPU data processing control center module performs self-diagnosis on the output circuit of the signal output type in the multiple signal output modules according to the set signal output type, and determines whether there is a fault. When there is a fault, the wireless module is enabled, otherwise the multiple signal output modules are used; then the pressure difference is calculated according to the received total pressure and static pressure, and the wind speed measurement result is calculated according to the differential pressure principle; the wind direction is determined according to the vortex street principle and the electrical signals collected by the two ultrasonic receiving probes, and the wind speed measurement result is calculated; the wind speed measurement result calculated according to the differential pressure principle and the wind speed measurement result calculated according to the vortex street principle are compared, and when the difference is within the error range, it is determined to be working normally, and then it is further determined whether the current wind speed measurement result is greater than the set threshold value. If so, the wind speed measurement result calculated according to the vortex street principle is taken and sent to the data display and remote control signal processing module, otherwise the wind speed measurement result calculated according to the differential pressure principle is taken and sent to the data display and remote control signal processing module, and sent to the wireless module or the multiple signal output modules at the same time; The display module is used to display the wind speed measurement result; The various signal output modules are used to transmit wind speed measurement results to the substation switch and the host computer through current output, frequency output and RS485 bus output; The wireless module is electrically connected to the CPU data processing control center module and is used for wirelessly transmitting the wind speed measurement result to the wireless substation switch and the host computer.

6. The wind speed sensor for coal mine according to claim 5, characterized in that: The method for determining the wind direction based on the vortex street principle and the electrical signals collected by two ultrasonic receiving probes is as follows: A generating rod is set in the middle position of two groups of ultrasonic transmitting probes and ultrasonic receiving probes placed opposite each other. When the wind direction is from the first ultrasonic transmitting probe and the first ultrasonic receiving probe to the second ultrasonic transmitting probe and the second ultrasonic receiving probe, the ultrasonic wave received by the second ultrasonic receiving probe will be affected by the vortex generated by the wind passing through the generating rod, and the collected electrical signal will be larger. When the wind direction is from the second ultrasonic transmitting probe and the second ultrasonic receiving probe to the first ultrasonic transmitting probe and the first ultrasonic receiving probe, the ultrasonic wave received by the first ultrasonic receiving probe will be affected by the vortex generated by the wind passing through the generating rod, and the collected electrical signal will be larger. The wind direction is then judged by the size of the electrical signals collected by the two ultrasonic receiving probes.

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