Anti-interference self-calibration mining coal piling height sensor

Abstract

The invention discloses an anti-interference self-calibration mining coal piling height sensor, and relates to the field of height sensors, the anti-interference self-calibration mining coal piling height sensor comprises a sensing mechanism used for monitoring the coal piling height, a lifting rope used for pulling the sensing mechanism, and a positioning frame arranged around the sensing mechanism, the top of the sensing mechanism is fixedly provided with a connection block used for connecting the lifting rope, and the connection block is fixedly provided with a positioning block used for positioning the lifting rope. One ends of the four lifting ropes are fixedly connected to the periphery of the connecting block, and the other ends of the lifting ropes are fixedly connected with collecting rods used for winding the lifting ropes. The influence of an external signal on the sensing mechanism is reduced by arranging the first interlayer and the second interlayer, the self-calibration module collects data of an external environment through the data acquisition module, the calibration module compares the data collected by the data acquisition module with a standard value and calculates an error needing to be compensated, and the self-calibration module performs self-calibration on the error. Therefore, the effect of improving the accuracy of the detection data is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of height sensors, and particularly to an anti-interference self-calibrating coal heap height sensor for mines. Background Art

[0002] A coal heap height sensor is a device used to monitor the height of a coal heap. In a coal mine belt conveyor system and a coal bunker storage system, it can monitor the height of the coal heap in real time. When the height of the coal heap reaches or exceeds a set limit value, it issues an alarm signal in a timely manner, causing related equipment such as a belt conveyor to stop working, avoiding the coal heap from piling up too high and submerging the head of the conveyor, preventing equipment failures and possible safety accidents, and also avoiding coal bunker overflow and endangering the safety of personnel and equipment.

[0003] For example, the "novel coal heap sensor for mines" with the publication number CN208171375U includes a coal heap upper cover, a coal heap lower housing, a coal heap plastic base, a nozzle, a circuit board, an adjustable contact rod, and a fixed mounting plate. A lifting ring is provided at the top of the coal heap upper cover, and the lifting ring is fixedly connected to the coal heap upper cover by threading. A first sealing ring is provided between the coal heap upper cover and the coal heap lower housing, and a second sealing ring is provided between the coal heap lower housing and the coal heap plastic base.

[0004] However, in the prior art, temperature is one of the important factors affecting the accuracy of height sensors. Different temperatures will cause the materials of the sensors to expand or contract, change the structural dimensions of the sensors, and affect their measurement performance. During the process of piling coal, after the height sensor absorbs heat, the dimensions of its internal structure will change slightly, which will directly lead to errors in the measurement results. Moreover, after the traditional sensor is used for a period of time, during the long-term operation of the height sensor, it is easy to cause a decline in measurement performance due to component aging and temperature drift, and its accuracy will deviate from the initial calibration value. If it is not recalibrated in time, the measurement error will gradually increase. Summary of the Invention

[0005] The purpose of the present invention is to provide an anti-interference self-calibrating coal heap height sensor for mines, so as to solve the problem that after the height sensor absorbs heat, the dimensions of its internal part of the structure will change slightly, which will directly lead to errors in the measurement results as put forward in the above background art.

[0006] To achieve the above object, the present invention provides the following technical solution: An anti-interference self-calibrating coal heap height sensor for mines, which includes a sensing mechanism for monitoring the coal heap height, a suspension rope for pulling the sensing mechanism, and a positioning frame deployed around the sensing mechanism. A connection block for connecting the suspension rope is fixedly installed at the top of the sensing mechanism. One ends of the four suspension ropes are respectively fixedly connected to the periphery of the connection block. The other ends of the suspension ropes are fixedly connected to a collecting rod for winding the suspension ropes. The collecting rod is rotatably installed at the bottom of the positioning frame. The sensing mechanism takes itself as the coordinate origin, takes the vertical distance between the sensing mechanism and the positioning frame as the X-axis and Y-axis, and takes the vertical height of the positioning frame itself as the Z-axis to establish a space coordinate system; The sensing mechanism includes a sensor main body, an anti-interference module, and a self-calibration module. The anti-interference module is used to reduce the interference of external signals on the sensor main body. The self-calibration module is used to calibrate the initial data and detection data of the sensor main body. The anti-interference module includes a first layer and a second layer. The first layer is fixedly installed on the outer shell of the sensor main body. The second layer is a metal mesh layer covering the outer wall of the first layer; The self-calibration module includes a data acquisition module and a calibration module. The data acquisition module is used to acquire height data and temperature data and transmit the data to the calibration module. The calibration module is used to adjust the sensor output, including a calibration unit and an error compensation unit. During use, the calibration unit combines the detected value with the standard value to calculate the error data, and then transmits each value to the error compensation unit to calculate the error to be compensated. After the error compensation unit calculates, it feeds back the calculation result to the calibration unit.

[0007] Preferably, the calibration unit includes the following steps: A1. Trigger condition: Trigger regularly; A2. Perform calibration: Acquire the data of the sensor main body and temperature data in the current environment; A3. Verify the calibration result: Verify the calibrated measurement value at a known height.

[0008] Preferably, the calibration unit exchanges data with the error compensation unit and sequentially executes a zero-point self-calibration unit, a linear self-calibration unit, and a temperature compensation unit; The zero-point self-calibration unit is used to eliminate the zero-point offset error of the sensor, that is, to adjust the sensor output under known zero-point conditions; The linear self-calibration unit is used to reduce the linear error of the sensor; The temperature compensation unit is used to calculate the influence value of temperature on the sensor.

[0009] Preferably, the zero-point self-calibration unit includes the following: B1. The sensor is in an environment at a known height, which is the zero height, and at the same time, ensure that the environment at this height is in a stable state; B2. Collect data: Collect N sample data at the zero height ; B3. Calculate the zero offset: Calculate the zero offset value , ; B4. Apply zero compensation: Compensate all subsequent measurement values with the compensation value being , 。

[0010] Preferably, the linear self-calibration unit includes the following: C1. Collect the sensor output value at a known height ; ; C2. Establish an error model. There is a linear relationship between the sensor output value and the actual height, and the calculation formula is: In the formula, is the gain coefficient, is the variance, is the random error; C3. Use the least squares method to fit and : ; ; In the formula, M is the number of samples; C4. Apply linear compensation: Compensate all subsequent measurement values with the compensation value being , 。

[0011] Preferably, the temperature compensation unit includes the following: D1. Collect data. Use a temperature sensor to collect the temperature T at the current height ; D2. Establish a temperature error model: , in the formula is the temperature compensation coefficient, and the temperature compensation coefficient is between and , , is the reference temperature, that is, the temperature reference value corresponding to the current height; D3. Apply temperature compensation.

[0012] Preferably, one side of the top of the positioning frame is fixedly installed with a guide rod, and the lower surface of the top of the positioning frame is rotatably installed with a threaded rod. The threaded rod is obliquely below the guide rod, and one end of the threaded rod is fixedly connected with a second reduction motor. The second reduction motor is fixedly installed at one end of the top of the positioning frame; A connecting rod is rotatably connected between the collecting rod and the limiting block. One side of the connecting rod is fixedly installed with an extension rod, and one end of the extension rod is threadedly connected to the outer wall of the threaded rod.

[0013] Preferably, a limiting block is sleeved on the outer wall of the guide rod, the suspension rope is lapped on the surface of the limiting block, and a first reduction motor is fixedly installed at the bottom of the positioning frame. The output shaft of the first reduction motor is fixedly connected with a rotating rod through a coupling.

[0014] Preferably, an arc-shaped convex block is fixedly installed on the outer wall of the rotating rod. The collecting rod is sleeved on the outer wall of the rotating rod through the arc-shaped convex block, and a through hole adapted to the arc-shaped convex block and the rotating rod is formed inside the collecting rod.

[0015] Preferably, a partition ring is rotatably installed inside the collecting rod, the suspension rope is wound on the outer wall of the partition ring, a blocking block is rotatably connected to the inner wall of the partition ring through a torsion spring, a ratchet wheel is fixedly installed at the edge of the through hole, and one end of the blocking block is lapped in the tooth groove of the ratchet wheel.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. In the present invention, by providing a first partition layer and a second partition layer to reduce the influence of external signals on the sensing mechanism, the self-calibration module collects data of the external environment through the data acquisition module, and the calibration module compares the data collected by the data acquisition module with the standard value and calculates the error that needs to be compensated, so as to improve the accuracy of the detection data. The positioning frame around the sensing mechanism can be used as a reference for the space coordinate system. When actually used, the sensing mechanism establishes a coordinate system with itself as the coordinate origin, which can greatly improve the accuracy of the height detection data.

[0017] 2. In the present invention, the calibration unit cooperates with the error compensation unit to execute the zero-point self-calibration unit, the linear self-calibration unit and the temperature compensation unit. When actually used, during the long-term and continuous height measurement process, the errors accumulated due to the passage of time and the increase in the number of measurements are eliminated. The linear self-calibration unit can automatically correct the sensing mechanism when a non-linear deviation occurs, so that the output of the sensing mechanism and the input maintain a linear relationship as much as possible, ensuring an accurate corresponding relationship between the measured value and the actual value within the entire measurement range. The temperature compensation unit can correct the measurement error caused by thermal expansion and contraction according to the temperature change situation to ensure the accuracy of the measurement.

[0018] 3. In the present invention, a first reduction motor and a second reduction motor are provided on the positioning frame. The first reduction motor is used to adjust the height of the sensing mechanism, and the second reduction motor is used to adjust the horizontal position of the sensing mechanism. Their combined use can meet various requirements of coal stacking, and the sufficient moving area can ensure that the sensing mechanism can monitor the height of the coal pile in each area to prevent monitoring dead spots. By continuously moving the sensing mechanism, it can obtain more data, which can be used as a basis for calibration to assist in improving the accuracy of the detection results. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a three-dimensional structural schematic diagram of an anti-interference self-calibrating mine coal pile height sensor of the present invention; Figure 2 is a partial three-dimensional structural schematic diagram of an anti-interference self-calibrating mine coal pile height sensor of the present invention; Figure 3 is a planar structural schematic diagram of an anti-interference self-calibrating mine coal pile height sensor of the present invention; Figure 4 is a connection and structural schematic diagram of a connecting rod, a limit block and a collecting rod of an anti-interference self-calibrating mine coal pile height sensor of the present invention; Figure 5 is a planar structural schematic diagram of a connecting rod and a half-sectional schematic diagram of a collecting rod of an anti-interference self-calibrating mine coal pile height sensor of the present invention; Figure 6 is of the present invention Figure 5 a magnified structural schematic diagram of part A; Figure 7 is a planar structural schematic diagram of a sensing mechanism of an anti-interference self-calibrating mine coal pile height sensor of the present invention; Figure 8 is a module schematic diagram of a sensing mechanism of an anti-interference self-calibrating mine coal pile height sensor of the present invention.

[0020] In the figure: 1, connecting block; 2, sensing mechanism; 3, suspension rope; 4, collecting rod; 5, rotating rod; 6, first reduction motor; 7, positioning frame; 8, arc-shaped convex block; 21, first partition layer; 22, second partition layer; 23, data acquisition module; 24, calibration module; 241, calibration unit; 242, error compensation unit; 243, zero-point self-calibration unit; 244, linear self-calibration unit; 245, temperature compensation unit; 41, dividing ring; 42, ratchet; 43, blocking block; 44, through hole; 71, threaded rod; 72, guide rod; 73, limit block; 74, connecting rod; 75, second reduction motor; 76, extension rod. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] Referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 7 and Figure 8 as shown: An anti-interference self-calibrating mine coal heap height sensor includes a sensing mechanism 2 for monitoring the coal heap height, a suspension rope 3 for pulling the sensing mechanism 2, and a positioning frame 7 deployed around the sensing mechanism 2. A connection block 1 for connecting the suspension rope 3 is fixedly installed at the top of the sensing mechanism 2. One ends of the four suspension ropes 3 are respectively fixedly connected around the connection block 1. The other ends of the suspension ropes 3 are fixedly connected to a collecting rod 4 for winding the suspension ropes 3. The collecting rod 4 is rotatably installed at the bottom of the positioning frame 7. The positioning frame 7 is arranged at the edge of the sensing mechanism 2 and perpendicularly to each other to form a quadrilateral structure. The sensing mechanism 2 takes itself as the coordinate origin, takes the vertical distance between the sensing mechanism 2 and the positioning frame 7 as the x-axis and y-axis, and takes the vertical height of the positioning frame 7 itself as the Z-axis to establish a space coordinate system; The sensing mechanism 2 includes a sensor main body, an anti-interference module, and a self-calibration module. The anti-interference module is used to reduce the interference of external signals on the sensor main body, and the self-calibration module is used to calibrate the initial data and detection data of the sensor main body. The anti-interference module includes a first layer 21 and a second layer 22 arranged in sequence from the inside to the outside. The first layer 21 is fixedly installed on the outer shell of the sensor main body, and the second layer 22 is coated on the outer wall of the first layer 21. In this embodiment, the second layer is preferably a metal mesh layer structure, and the first layer 21 is made of fiberglass, which can not only play an anti-interference role, but also ensure the structural strength of the sensing mechanism 2.

[0023] The self-calibration module includes a data acquisition module 23 and a calibration module 24. The data acquisition module 23 is used to acquire height data and temperature data and transmit the data to the calibration module 24. The calibration module 24 is used to adjust the sensor output, including a calibration unit 241 and an error compensation unit 242. When in use, the calibration unit 241 combines the detected value with the standard value for calculation, and then transmits each value to the error compensation unit 242 to calculate the error that needs to be compensated. After the error compensation unit 242 finishes the calculation, it feeds back the calculation result to the calibration unit 241.

[0024] In this embodiment, one end of the suspension rope 3 is wound around the collecting rod 4, and the other end is fixedly connected to the connecting block 1 after passing around the limiting block 73. The sensing mechanism 2 is suspended by the connecting block 1. Four suspension ropes 3 respectively suspend the four sides of the connecting block 1 to ensure the stability of the sensing mechanism 2. When detecting the height of the coal pile, the sensing mechanism 2 stays above the coal pile under the pulling of the suspension ropes 3. The sensing mechanism 2 emits ultrasonic signals, and the signals propagate in the air to the surface of the coal pile and then are reflected back. The sensing mechanism 2 calculates the distance between the sensing mechanism 2 and the surface of the coal pile by measuring the time difference between the transmitted signal and the received echo, and then obtains the height of the coal pile.

[0025] During the process of monitoring the height of the coal pile, the sensing mechanism 2 takes itself as the origin, takes the vertical distance between it and the positioning frame 7 as the X-axis and the X-axis, and takes the vertical height of the positioning frame 7 as the Z-axis to establish a spatial coordinate system, so as to obtain the accurate height and horizontal position of the sensing mechanism 2. The data acquisition module 23 collects height data and temperature data in real time. After these data are sent to the calibration module 24, the calibration unit 241 calculates the data under various conditions. These data are then calculated by the error compensation unit 242 to obtain the error results that need to be compensated. Finally, the calibration unit 241 adjusts the display result according to the error results.

[0026] According to Figure 8 shown, the calibration unit 241 includes the following steps: A1. Trigger condition: Trigger regularly; A2. Perform calibration: Collect the data of the sensor body and temperature data in the current environment; A3. Verify the calibration result: Verify the calibrated measured value at a known height.

[0027] The calibration unit 241 exchanges data with the error compensation unit 242 and sequentially executes the zero-point self-calibration unit 243, the linear self-calibration unit 244 and the temperature compensation unit 245; Among them, the specific way of exchanging data is that the calibration unit 241 combines the detection value obtained by the sensor body with a predetermined standard value for calculation, and then transmits the calculated result to the error compensation unit 242. The error compensation unit 242 calculates the error that needs to be compensated, and then feeds the calculation result back to the calibration unit 241; The zero-point self-calibration unit 243 is used to eliminate the zero-point offset error of the sensor, that is, to adjust the sensor output under known zero-point conditions. The zero-point self-calibration unit 243 includes the following content: B1. The sensor is in an environment with a known height, which is the zero-point height, and at the same time ensure that the environment at this height is in a stable state; B2. Collect data: Collect N sample data at the zero-point height ; B3. Calculate zero offset: Calculate the zero offset value , ; B4. Apply zero compensation: Compensate all subsequent measurement values with the compensation value being , .

[0028] The linear self - calibration unit 244 is used to eliminate the linear error of the sensor. The linear self - calibration unit 244 includes the following: C1. Collect the sensor output value at a known height ; ; C2. Establish an error model. There is a linear relationship between the sensor output value and the actual height, and the calculation formula is: , where in the formula is the gain coefficient, is the variance, is the random error; C3. Use the least - squares method to fit and : ; ; where M is the number of samples; C4. Apply linear compensation: Compensate all subsequent measurement values with the compensation value being , .

[0029] The temperature compensation unit 245 is used to reduce the influence of temperature change on the sensor. The temperature compensation unit 245 includes the following: D1. Collect data. Use a temperature sensor to collect the temperature T at the current height ; D2. Establish a temperature error model: , where in the formula is the temperature compensation coefficient, and the temperature compensation coefficient is between and , , is the reference temperature, that is, the temperature reference value corresponding to the current height; D3. Apply temperature compensation.

[0030] In this embodiment, during the manufacturing, installation, and use of the height sensor, its output at the zero position is not zero, that is, there is an initial deviation. In some systems that require long-term and continuous height measurement, if the zero point of the sensor is inaccurate, with the passage of time and the increase in the number of measurements, errors will gradually accumulate, which may cause the measurement results to deviate significantly from the true values. The zero-point self-calibration unit 243 can collect multiple sample data and calculate the zero-point offset to determine the compensation value at the same time, which can timely correct the zero-point error, prevent the accumulation of errors, and ensure the long-term stable operation of the system. The measurement principle of the height sensor is based on a certain linear relationship, and the zero point is an important reference point to determine this linear relationship. Accurate zero-point calibration helps to ensure the linearity of the sensor within the entire measurement range, so that a stable and accurate linear correspondence relationship is maintained between the sensor output and the measured height, thereby improving the accuracy of measurement values at different heights. After zero-point calibration, the sensor can return to the accurate zero position at the beginning of each measurement, thus improving the repeatability of measurement, that is, for the measurement of the same height, the results obtained each time can be more consistent, reducing the discreteness of the measurement results and making the measurement results of the system more reliable and repeatable; The linear self-calibration unit 244 can monitor the relationship between the output signal and the input physical quantity of the sensor in real time. When it is found that the measurement curve shows a non-linear deviation, an error model is established based on the sensor output value, and the least squares method is used to calculate the compensation value at the same time to automatically correct it, so that the output of the sensor and the input maintain a linear relationship as much as possible, ensuring that there is an accurate correspondence relationship between the measured value and the actual value within the entire measurement range and improving the measurement accuracy. The linear self-calibration unit 244 can perform linear calibration on the sensor regularly or in real time, timely adjust the linearity changes caused by various factors, ensure that the sensor always maintains stable measurement performance during long-term use, reduce the fluctuations and drifts of the measurement results, and in practical applications, the sensor will be affected by various interference signals, such as electromagnetic interference, noise, etc. These interferences may cause the output of the sensor to be distorted and affect the linearity of the measurement. By calculating the compensation value to correct the measured data after being interfered, the sensor can still maintain stable linear measurement in an environment with interference, improving the reliability of the measurement; Many components of the sensor will expand and contract due to temperature changes, which may cause changes in the size and shape of the measuring element, thereby affecting the accuracy of the measurement results. The performance of electronic components is greatly affected by temperature. For example, the parameters of components such as resistors and capacitors will change with temperature, which will cause changes in the circuit characteristics of the sensor, affecting the output signal of the sensor. Moreover, temperature changes are likely to cause zero drift of the sensor, that is, the output value of the sensor when there is no input signal changes. The temperature compensation unit 245 can monitor the temperature of the sensing mechanism 2 in real time and adjust the zero point according to the temperature change, controlling the zero drift within the minimum range to ensure the stability and reliability of the sensor measurement, compensating for the performance fluctuations of electronic components caused by temperature changes, and enabling the sensor to output stable and accurate signals.

[0031] According to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 and Figure 6 As shown, the positioning frame 7 is of I-shaped structure. One side of the top of the positioning frame 7 is fixedly installed with a guide rod 72. The lower surface of the top of the positioning frame 7 is rotatably installed with a threaded rod 71. The threaded rod 71 is obliquely below the guide rod 72. One end of the threaded rod 71 is drivingly connected to a second reduction motor 75, and the second reduction motor 75 is fixedly installed at one end of the top of the positioning frame 7; A connecting rod 74 is rotatably connected between the collecting rod 4 and the limiting block 73. One side of the connecting rod 74 is fixedly installed with an extension rod 76. One end of the extension rod 76 is threadedly connected to the outer wall of the threaded rod 71; A limiting block 73 is sleeved on the outer wall of the guide rod 72. The suspension rope 3 is lapped on the surface of the limiting block 73. The bottom of the positioning frame 7 is fixedly installed with a first reduction motor 6. The output shaft of the first reduction motor 6 is fixedly connected to a rotating rod 5 through a coupling; An arc-shaped convex block 8 is fixedly installed on the outer wall of the rotating rod 5. The collecting rod 4 is sleeved on the outer wall of the rotating rod 5 through the arc-shaped convex block 8. A through hole 44 whose shape is adapted to the arc-shaped convex block 8 and the rotating rod 5 is opened inside the collecting rod 4; A partition ring 41 is rotatably installed inside the collecting rod 4. The suspension rope 3 is wound around the outer wall of the partition ring 41. A blocking block 43 is rotatably connected to the inner wall of the partition ring 41 through a torsion spring. A ratchet 42 is fixedly installed at the edge of the through hole 44. One end of the blocking block 43 is lapped in the tooth groove of the ratchet 42.

[0032] In this embodiment, the positioning frame 7 is used to determine the position of the lifting rope 3 and wind the lifting rope 3 around the collecting rod 4 on the outer wall of the rotating rod 5. During actual use, the four first reduction motors 6 simultaneously drive the rotating rod 5 to drive the partition ring 41 to wind the lifting rope 3 and raise the height of the lifting and sensing mechanism 2. When it is necessary to adjust the horizontal position of the sensing mechanism 2, the first reduction motor 6 drives the threaded rod 71, drives the connecting rod 74 through the extension rod 76, and uses the connecting rod 74 to drive the limiting block 73 and the collecting rod 4 simultaneously to achieve the purpose of adjusting the horizontal position of the sensing mechanism 2; Combined with Figure 3 、 Figure 5 and Figure 6 , when the height of the sensing mechanism 2 changes, the collecting rod 4 rotates clockwise driven by the rotating rod 5. The collecting rod 4 pushes the blocking block 43 through the ratchet 42, prompting the partition ring 41 to also rotate clockwise, and wind the lifting rope 3 onto the surface of the partition ring 41. The shape of the arc-shaped convex block 8 on the outer wall of the rotating rod 5 is adapted to the through hole 44, which can prevent the collecting rod 4 from reversing and improve the stability of the sensing mechanism 2; When the sensing mechanism 2 moves horizontally, the second reduction motor 75 in its moving direction operates to pull the lifting rope 3 on the moving route of the sensing mechanism 2 to achieve the purpose of adjusting the horizontal position of the sensing mechanism 2. During this process, the connecting block 1 drives the partition ring 41 to pull the partition ring 41 to rotate counterclockwise through the other three lifting ropes 3 to release more lifting ropes 3 for the connecting rod 74 to move.

[0033] Usage method and working principle of this device: During actual use, the sensing mechanism 2 is suspended above the coal pile by four lifting ropes 3 for height detection. During the process of piling coal, the sensing mechanism 2 establishes a space coordinate system with itself as the origin, emits ultrasonic signals, the signals propagate in the air to the surface of the coal pile and then are reflected back. The sensing mechanism 2 calculates the distance between the sensing mechanism 2 and the surface of the coal pile by measuring the time difference between the transmitted signal and the received echo and combining the propagation speed of ultrasonic waves in the air, so as to obtain height information. During the detection process, the first layer 21 and the second layer 22 can reduce the interference of external signals on the sensing mechanism 2; The four first reduction motors 6 simultaneously drive the rotating rod 5 to wind the lifting rope 3 onto the surface of the partition ring 41 to achieve the purpose of raising the height of the sensing mechanism 2. When it is necessary to adjust the horizontal position of the sensing mechanism 2, the first reduction motor 6 drives the threaded rod 71, drives the connecting rod 74 through the extension rod 76, and uses the connecting rod 74 to drive the limiting block 73 and the collecting rod 4 simultaneously to achieve the purpose of adjusting the horizontal position of the sensing mechanism 2; The zero-point self-calibration unit 243 can timely correct the zero-point error, prevent the accumulation of errors, ensure the long-term stable operation of the system. After zero-point calibration, the sensor can return to the accurate zero-point position at the beginning of each measurement, thus improving the repeatability of the measurement; The linear self-calibration unit 244 can monitor the relationship between the output signal of the sensor and the input physical quantity in real time. When a non-linear deviation appears in the measurement curve, it automatically corrects it to make the output and input of the sensor maintain a linear relationship as much as possible, ensuring an accurate corresponding relationship between the measured value and the actual value throughout the measurement range; The temperature compensation unit 245 can monitor the temperature of the sensing mechanism 2 in real time, adjust the zero point according to the temperature change, control the zero point drift within the minimum range, ensure the stability and reliability of the sensor measurement, and compensate for the performance fluctuations of the electronic components caused by temperature changes by adopting a specific algorithm, so that the sensor outputs a stable and accurate signal.

[0034] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An anti-interference self-calibration coal pile height sensor for mining, characterized by: The invention comprises a sensing mechanism (2) for monitoring the height of a coal pile, a lifting rope (3) for pulling the sensing mechanism (2), and a positioning frame (7) arranged around the sensing mechanism (2); a connecting block (1) for connecting the lifting rope (3) is fixedly installed on the top of the sensing mechanism (2); one end of four lifting ropes (3) are respectively fixedly connected to the four sides of the connecting block (1); the other end of the lifting rope (3) is fixedly connected to a collecting rod (4) for winding up the lifting rope (3); the collecting rod (4) is rotatably installed on the bottom of the positioning frame (7); the sensing mechanism (2) establishes a spatial coordinate system with itself as the coordinate origin, the vertical distance between the sensing mechanism (2) and the positioning frame (7) as the X-axis and the Y-axis, and the vertical height of the positioning frame (7) itself as the Z-axis; The sensing mechanism (2) comprises a sensor body, an anti-interference module and a self-calibration module, wherein the anti-interference module is used to reduce interference of external signals on the sensor body, and the self-calibration module is used to calibrate initial data and detection data of the sensor body, and the anti-interference module comprises a first partition layer (21) and a second partition layer (22), wherein the first partition layer (21) is fixedly mounted on the outer shell of the sensor body, and the second partition layer (22) is a metal mesh layer covering the outer wall of the first partition layer (21); The self-calibration module comprises a data acquisition module (23) and a calibration module (24); the data acquisition module (23) is used to acquire altitude data and temperature data and transmit the data to the calibration module (24); the calibration module (24) is used to adjust the sensor output and comprises a calibration unit (241) and an error compensation unit (242); when in use, the calibration unit (241) combines the detection value with the standard value to calculate error data, and then transmits each value to the error compensation unit (242) to calculate the error to be compensated; after the error compensation unit (242) completes the calculation, the calculation result is fed back to the calibration unit (241).

2. The anti-interference self-calibration coal pile height sensor for mining according to claim 1, characterized in that: The calibration unit (241) comprises the following steps: A1. Triggering conditions: regular triggering; A2. Perform calibration: collect data and temperature data of the sensor body in the current environment; A3. Verify calibration results: Verify the calibrated measurements at a known altitude.

3. The anti-interference self-calibration coal pile height sensor for mining according to claim 2, characterized in that: The calibration unit (241) exchanges data with the error compensation unit (242) and sequentially executes a zero point self-calibration unit (243), a linearity self-calibration unit (244) and a temperature compensation unit (245); The zero point self-calibration unit (243) is used to eliminate the zero point offset error of the sensor, that is, to adjust the sensor output under a known zero point condition; The linear self-calibration unit (244) is used to reduce the linear error of the sensor; The temperature compensation unit (245) is used to calculate the impact value of temperature on the sensor.

4. The anti-interference self-calibration coal pile height sensor for mining according to claim 3, characterized in that: The zero point self-calibration unit (243) includes the following contents: B1. The sensor is in an environment with a known height, which is the zero point height; B2. Collect data: Collect N sample data at zero altitude ; B3. Calculate zero point offset: Calculate zero point offset , ; B4. Apply zero compensation: for all subsequent measurements Compensation is performed, and the compensation value is , .

5. The anti-interference self-calibration coal pile height sensor for mining according to claim 3, characterized in that: The linear self-calibration unit (244) includes the following contents: C1. At a known height Collect sensor output values ; C2. Establish an error model. There is a linear relationship between the sensor output value and the actual height. The calculation formula is: , in the formula is the gain coefficient, is the variation, is a random error; C3. Fitting using the least squares method and : ； ； Where M is the sample size; C4. Apply linear compensation: for all subsequent measurements Compensation is performed, and the compensation value is , .

6. The anti-interference self-calibration coal pile height sensor for mining according to claim 3, characterized in that: The temperature compensation unit (245) includes the following contents: D1. Collect data and use the temperature sensor to collect the current height Temperature T below; D2. Establish temperature error model: , where is the temperature compensation coefficient. to between, , is the reference temperature, that is, the temperature reference value corresponding to the current altitude; D3. Apply temperature compensation.

7. The anti-interference self-calibration coal pile height sensor for mining according to claim 1, characterized in that: A guide rod (72) is fixedly mounted on one side of the top of the positioning frame (7); a threaded rod (71) is rotatably mounted on the lower surface of the top of the positioning frame (7); the threaded rod (71) is located obliquely below the guide rod (72); one end of the threaded rod (71) is fixedly connected to a second reduction motor (75); the second reduction motor (75) is fixedly mounted on one end of the top of the positioning frame (7); A connecting rod (74) is rotatably connected between the collecting rod (4) and the limiting block (73), an extension rod (76) is fixedly mounted on one side of the connecting rod (74), and one end of the extension rod (76) is threadedly connected to the outer wall of the threaded rod (71).

8. The anti-interference self-calibration coal pile height sensor for mining according to claim 7, characterized in that: A limit block (73) is sleeved on the outer wall of the guide rod (72), the suspension rope (3) is overlapped on the surface of the limit block (73), a first reduction motor (6) is fixedly mounted on the bottom of the positioning frame (7), and an output shaft of the first reduction motor (6) is fixedly connected to a rotating rod (5) via a coupling.

9. The anti-interference self-calibration coal pile height sensor for mining according to claim 8, characterized in that: An arc-shaped protrusion (8) is fixedly mounted on the outer wall of the rotating rod (5); the collecting rod (4) is sleeved on the outer wall of the rotating rod (5) via the arc-shaped protrusion (8); and a through hole (44) having a shape matching that of the arc-shaped protrusion (8) and the rotating rod (5) is provided inside the collecting rod (4).

10. The anti-interference self-calibration coal pile height sensor for mining according to claim 9, characterized in that: A separation ring (41) is rotatably mounted inside the collecting rod (4), the suspension rope (3) is wound around the outer wall of the separation ring (41), a blocking block (43) is rotatably connected to the inner wall of the separation ring (41) via a torsion spring, a ratchet (42) is fixedly mounted at the edge of the through hole (44), and one end of the blocking block (43) is overlapped in the tooth groove of the ratchet (42).

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