Intelligent laser flow scale for air cushion machine and implementation method

Abstract

The invention discloses an intelligent laser flow scale for an air cushion machine and an implementation method, and belongs to the technical field of belt conveyors. An intelligent laser flow scale for an air cushion machine comprises a belt body, a driving roller and a turnabout roller are installed at the two ends of the belt body respectively, a speed detector is installed on the turnabout roller, a laser range finder is installed above the belt body, and a volume-weight instrument is installed at the tail of the belt body. And data acquired by the laser range finder, the speed detector and the volume-weight instrument are transmitted to the accounting device. The problems that in the prior art, interference factors are many, the application range cannot be expanded, and the structure is complex are solved, non-contact, high-precision and real-time weight measurement can be achieved, meanwhile, the measurement efficiency and accuracy are improved, and the device has the advantages of being high in measurement precision, high in measurement speed and easy and convenient to operate, can be universally applied to various belt conveyors and has wide application prospects. And the scale body has the advantages of wide practicability, simple structure and small installation workload.

Description

Technical Field

[0001] The invention relates to the technical field of belt conveyors, and in particular to an intelligent laser flow scale for an air cushion machine and an implementation method thereof. Background Art

[0002] Air cushion belt conveyor (hereinafter referred to as air cushion machine) is a special belt conveyor. Unlike common belt conveyors that bear pressure with rollers, it is a belt conveyor that supports the conveyor belt and materials with a thin air film. When the air source provides air with a certain pressure and flow rate to the air chamber, the air in the air chamber overflows through the throttle holes on the disc groove, forming a layer of air film with a certain pressure between the conveyor belt and the disc groove, called an air cushion, which supports the conveyor belt and the materials on it. In this way, the roller friction of ordinary belt conveyors is changed to fluid friction with air as the medium, which reduces the running resistance and brings many advantages.

[0003] A belt scale is a metering device that automatically and continuously weighs materials while they are being transported by a roller belt conveyor. It is characterized by a continuous and automatic weighing process, and usually requires no operator intervention to complete the weighing operation. In modern industrial process lines, belt scales are an important metering device and are widely used. They not only provide important parameters for production process control, but also play an important role in production batching. It can be said that the operation of a belt scale directly affects the normal progress of production.

[0004] The main components of the belt scale are the weighing part, the speed measuring part, and the signal processor. The weighing part mainly includes: scale frame, metering roller, weighing sensor and auxiliary mechanism (such as shaping roller, counterweight meter), etc. Its main function is to convert the weight signal into a voltage signal. The speed measuring part mainly measures the pulse speed to get the running speed of the belt. The signal processor processes the analog voltage value output by the weighing sensor and the speed signal output by the electronic speed sensor, and generates the load rate through the processing and calculation of the electronic calculator, and finally gets the instantaneous flow rate and cumulative flow rate of the material, and outputs the signal to other control devices or control systems at the same time. However, the existing belt scales still have the following disadvantages during use:

[0005] 1. Many interference factors: The weighing principle of the belt scale is to measure the weight of the material through the pressure carried by the conveyor belt, so the condition of the belt conveyor, such as belt tension, belt hardness, belt deviation, uncalibrated rollers, eccentric rollers, etc., has a great influence on the accuracy of the symmetry;

[0006] 2. The scope of application cannot be expanded: Since the key data in the weight measurement of the belt scale - pressure value, must be obtained through a weighing sensor, and for the air cushion machine, its conveyor belt is suspended during operation, and there is no condition to obtain this data, so the traditional belt scale cannot be applied to the air cushion machine;

[0007] 3. Complex structure: The traditional belt scale frame is large and complex. For example, the double-lever scale frame with counterweight in the multi-roller electronic belt scale often weighs more than 1000kg. During installation, the support and longitudinal beam of the conveyor must be reinforced. Therefore, it does not meet the existing needs. In this regard, we propose an intelligent laser flow scale for air cushion machines and its implementation method. Summary of the invention

[0008] The object of the present invention is to provide an intelligent laser flow scale for an air cushion machine and an implementation method thereof. By using a laser rangefinder, a speed detector and a bulk density meter to weigh the materials on the air cushion machine, non-contact, high-precision and real-time weight measurement can be achieved, while improving the measurement efficiency and accuracy. The laser rangefinder uses the time delay or phase difference of the laser beam to determine the distance, and has the advantages of high measurement accuracy, fast measurement speed and simple operation. It can be commonly used on various belt conveyors and has wide practicality. The scale body has a simple structure and a small installation workload. The laser rangefinder only needs to be fixed on the bracket below the air cushion machine cover plate, and there is no need to install various pressure sensors, thereby solving the problems raised in the above-mentioned background technology.

[0009] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an intelligent laser flow scale for an air cushion machine, comprising a belt body, a driving roller and a redirecting roller, wherein the driving roller and the redirecting roller are respectively installed at both ends of the belt body, a speed detector is installed on the redirecting roller, a laser rangefinder is installed above the belt body, two groups of laser rangefinders are arranged, which are respectively installed at both ends of the middle section of the air cushion machine, a bulk density meter is installed at the tail of the belt body, and data collected by the laser rangefinder, the speed detector and the bulk density meter are all transmitted to the accounting device.

[0010] Preferably, the accounting device comprises:

[0011] A signal receiver is used to receive and transmit real-time monitoring data and fixed data collected by a laser rangefinder, a speed detector and a bulk density meter;

[0012] A material accounting module, used to calculate the material on the belt body using the data transmitted by the signal receiver;

[0013] The display module is used to display the calculation results and process of the material accounting module, as well as the data collected by the laser rangefinder, speed detector and bulk density meter.

[0014] Preferably, the signal receiver comprises:

[0015] A receiving module is used to receive real-time monitoring data and fixed data collected by a laser rangefinder, a speed detector and a bulk density meter;

[0016] The transmission module is used to transmit the received real-time monitoring data and fixed data to the material accounting module

[0017] Preferably, the fixed data are the length between the two laser rangefinders and the height from the laser rangefinder to the bottom of the belt body, and the real-time measurement data are the running speed of the belt body, the material density monitored by the bulk density meter and the height from the laser rangefinder to the material.

[0018] Preferably, the material accounting module includes:

[0019] A calculation module, used to calculate the mass of the material on the belt body within a unit length, the material moving time within a unit length, and the instantaneous flow rate of the air cushion machine according to the output data of the signal receiver;

[0020] An integrator is used to calculate the data calculated by the calculation module and perform time integration on the calculated data to generate an output signal;

[0021] The accumulator is used to store the intermediate results generated in the weight calculation of the material on the belt body 1 and accumulate the weight data of each measurement.

[0022] Preferably, the calculation module specifically includes:

[0023] Calculate the material mass M on the belt body per unit length using the following formula:

[0024]

[0025] Calculate the material movement time t per unit length using the following formula:

[0026]

[0027] Calculate the instantaneous flow rate Q of the air cushion machine, the calculation formula is as follows:

[0028]

[0029] Where, L is the length between the two sets of laser rangefinders, H is the height from the laser rangefinder to the bottom of the air cushion skin, v is the running speed of the belt body measured by the speed detector, ρ is the material density measured by the bulk density meter, h is the height between the laser rangefinder and the material, and M is the material mass on the belt body per unit length.

[0030] Preferably, the calculation module further includes a detection device for monitoring the current deviation threshold state of the belt body, and the detection device includes:

[0031] A speed sensor is arranged on the output shaft of the driving roller and is used to detect the running speed of the belt body;

[0032] The tension sensor is installed at the drive roller or the redirection roller bearing to monitor the tension change of the belt body and determine whether the belt is affected by uneven force;

[0033] The eccentricity sensor is set at the axis of the driving roller or the redirecting roller, and determines the eccentricity of the roller by measuring the deviation between the axis and the roller;

[0034] Strain sensors are installed on the load-bearing part of the belt body, especially at the tension point or support wheel position of the belt body, to monitor the local stress and deformation of the belt, thereby reflecting the change in belt stiffness. When the belt stiffness weakens, the belt deformation increases and it is easy to deviate.

[0035] Vibration sensors are installed in the middle, on both sides or at the supporting points of the belt body to monitor the vibration amplitude and frequency of the belt in real time;

[0036] A timer, mounted on the frame of the belt body, is used to detect the running time of the belt;

[0037] Alarm: set on the frame of the belt body;

[0038] The calculation module controls the alarm to work based on the speed sensor, the tension sensor, the eccentricity sensor, the strain sensor, the vibration sensor, and the timer, including the following steps:

[0039] Step 1: The calculation module calculates the basic deviation index of the belt body based on the detection values ​​of the tension sensor, eccentricity sensor, strain sensor, vibration sensor, timer, and formula (1):

[0040]

[0041] Among them, X is the basic deviation index of the belt body, t represents the time variable, which is detected by the timer; T represents the upper limit of the time integral, that is, the time range of the formula calculation; T(t) represents the belt tension at a certain time t, which is detected by the tension sensor; E(t) represents the eccentricity of the roller on the belt body, which is detected by the eccentricity sensor; K(t) represents the stiffness of the belt body, which is detected by the strain sensor; M represents the load of the material transported on the belt, v represents the vibration amplitude of the belt, which is detected by the vibration sensor; W max Indicates the maximum vibration amplitude of the belt; W indicates the width of the belt; R min Indicates the minimum roughness of the belt surface;

[0042] Step 2: The calculation module calculates the nonlinear correction coefficient of the belt body offset based on the detection value of the speed sensor and formula (2):

[0043]

[0044] Where Y is the nonlinear correction coefficient of the belt body offset, D is the belt wear coefficient; R avg Indicates the average value of belt surface roughness; s v Indicates the belt running speed, which is detected by the speed sensor; s max Indicates the maximum speed of the belt;

[0045] Step 3: The calculation module is based on formula (1) and formula (2), and is calculated by formula (3).

[0046] Calculate the belt deviation index in the belt body:

[0047] Δ=X Y (three)

[0048] Step 4: The calculation module compares the deviation index of the belt in the belt body with the preset deviation index. When the deviation index of the belt in the belt body is greater than the preset deviation index, the calculation module controls the alarm to issue an alarm prompt.

[0049] Preferably, a controller is provided on the outside of the hopper, and the controller is electrically connected to the discharge valve to control the opening and closing of the discharge valve and the opening and closing degree of the valve plate;

[0050] The bulk density meter is electrically connected to the controller, and the bulk density meter detects the material density above the belt body in real time, and synchronizes the detected material density value to the controller in real time;

[0051] The laser rangefinder is electrically connected to the controller. The two laser rangefinders detect the distance to the upper surface of the material in real time, and calculate the real-time thickness of the material based on the height from the laser rangefinder to the bottom of the air cushion skin, and synchronize the detected real-time thickness value of the material to the controller;

[0052] The controller counts multiple material density values ​​and real-time material thickness values ​​within a unit time, and counts fluctuations in the material density values ​​and the real-time material thickness values. When the fluctuation is greater than a preset fluctuation range, it is determined that there is a blockage at the opening and closing of the material plate of the discharge valve, and the controller controls the opening and closing degree of the material plate of the discharge valve to perform a reciprocating adjustment of first increasing and then retracting;

[0053] The rule of reciprocating adjustment is that the opening and closing degree of the material plate increases by 10% from the initial position to the first position, then increases by 20% to the second position, then retracts from the second position to the first position, and then retracts from the first position to the initial position. The time interval of a reciprocating adjustment cycle is 3 to 5 minutes. After one interval of the reciprocating cycle, the fluctuation of the material density value and the real-time thickness value of the material is re-measured;

[0054] When the fluctuation of the material density value and the real-time thickness value measured again meets the preset range, the controller controls the material plate of the discharge valve to stop moving, otherwise repeats the previous adjustment until the fluctuation of the material density value and the real-time thickness value of the material meets the preset range.

[0055] A method for realizing an intelligent laser flow scale for an air cushion machine comprises the following steps:

[0056] Step 1: Obtain the length between the two laser distance meters and the height from the laser distance meter to the bottom of the belt body;

[0057] Step 2: Use a laser rangefinder to measure the material height when the belt body is running, use a speed detector to measure the running speed of the belt body, and use a bulk density meter to measure the density of the material;

[0058] Step 3: Calculate the material mass on the belt body per unit length using the length between the laser rangefinders, the height from the laser rangefinder to the bottom of the belt body, the material height when the belt body is running, the running speed of the belt body, the density of the material, and the height from the laser rangefinder to the material;

[0059] Step 4: Calculate the material moving time per unit length using the length between the two sets of laser rangefinders and the running speed of the belt body measured by the speed detector;

[0060] Step 5: Calculate the instantaneous flow rate of the air cushion machine using the material movement time per unit length and the material mass on the belt body per unit length.

[0061] Preferably, the method of using a laser rangefinder to measure the material height when the belt body is running specifically includes:

[0062] Use a laser rangefinder to emit a laser beam to the surface of the material and receive the reflected laser signal;

[0063] By measuring the running time of the laser beam, the distance from the material surface to the laser rangefinder is calculated, and then the material height when the belt body is running is obtained.

[0064] Compared with the prior art, the present invention has the following beneficial effects:

[0065] The present invention uses a laser rangefinder, a speed detector and a bulk density meter to weigh the materials on the air cushion machine, so as to achieve non-contact, high-precision and real-time weight measurement, and improve the measurement efficiency and accuracy. The laser rangefinder uses the time delay or phase difference of the laser beam to determine the distance, and has the advantages of high measurement accuracy, fast measurement speed and simple operation.

[0066] The present invention can measure the volume or volume change of the material by using a laser rangefinder in the weighing of the material of the air cushion machine, calculate the volume of the material by measuring the distance of multiple points, and then obtain the weight of the material by combining the density of the material. The speed detector can monitor the movement speed of the material on the air cushion machine in real time, and can more accurately calculate the weight change of the material within a specific time through the speed information, thereby improving the dynamic accuracy of weighing. The bulk density meter is used to measure the density of the material, and the accurate density information is combined with the volume measured by the laser rangefinder to accurately calculate the weight of the material. The present invention can be generally used on various belt conveyors and has wide practicability.

[0067] 3. The intelligent laser flow scale of the present invention has a simple structure and small installation workload. It only needs to fix the laser rangefinder on the bracket below the air cushion machine cover, and there is no need to install various pressure sensors. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 It is a schematic diagram of the plan structure of the intelligent laser flow scale for the air cushion machine of the present invention;

[0069] Figure 2 It is a front view structural schematic diagram of the intelligent laser flow scale for the air cushion machine of the present invention;

[0070] Figure 3 It is a schematic diagram of a calculation device of an intelligent laser flow scale for an air cushion machine of the present invention;

[0071] Figure 4 It is a schematic diagram of a method for realizing an intelligent laser flow scale for an air cushion machine of the present invention.

[0072] In the figure: 1. Belt body; 2. Driving roller; 3. Redirecting roller; 4. Laser rangefinder; 5. Speed ​​detector; 6. Bulk density meter; 7. Hopper; 8. Discharge valve. DETAILED DESCRIPTION

[0073] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0074] In order to solve the problems of many interference factors, limited application scope and complex structure of existing technologies, please refer to Figure 1-Figure 4 , this embodiment provides the following technical solutions:

[0075] An intelligent laser flow scale for an air cushion machine comprises a belt body 1, a driving roller 2 and a redirecting roller 3. The driving roller 2 and the redirecting roller 3 are respectively installed at both ends of the belt body 1. A speed detector 5 is installed on the redirecting roller 3 to measure the running speed of the belt. A laser rangefinder 4 is installed above the belt body 1. The laser rangefinder 4 is fixed to a bracket below the air cushion machine cover. Two groups of laser rangefinders 4 are arranged, which are respectively installed at both ends of the middle section of the air cushion machine. A bulk density meter 6 is installed at the tail of the belt body 1. Data collected by the laser rangefinder 4, the speed detector 5 and the bulk density meter 6 are all transmitted to a calculation device. A hopper 7 is arranged above the belt body 1, and a discharge valve 8 is provided at the discharge port of the hopper 7.

[0076] The flow scale has a simple structure and small installation workload. In terms of installation, it only needs to fix the laser rangefinder 4 on the bracket under the air cushion machine cover. It does not need to install various pressure sensors under the upper belt and remove the belt conveyor body like ordinary belt scales.

[0077] The bulk density meter 6 can monitor the density of the material on the belt body 1 in real time, timely reflect the quality changes of the material, and can accurately measure the density of the material, reducing human errors and measurement uncertainties. The automated measurement of the bulk density meter 6 reduces manual intervention and labor intensity, while also reducing material waste and increased production costs caused by inaccurate measurements. The bulk density meter 6 can also record measurement data to facilitate data tracing and quality control.

[0078] In summary, the bulk density meter 6 plays an important role in the material density detection on the belt body 1. It can not only improve the measurement accuracy and real-time performance, but also optimize the production process, reduce costs and improve efficiency, while achieving data traceability and quality control.

[0079] The accounting device comprises:

[0080] A signal receiver, used to receive and transmit real-time monitoring data and fixed data collected by the laser rangefinder 4, the speed detector 5 and the bulk density meter 6;

[0081] A material accounting module, used to calculate the material on the belt body 1 using the data transmitted by the signal receiver;

[0082] The display module is used to display the calculation results and process of the material accounting module, as well as the data collected by the laser rangefinder 4, the speed detector 5 and the bulk density meter 6.

[0083] The signal receiver comprises:

[0084] A receiving module is used to receive real-time monitoring data and fixed data collected by the laser rangefinder 4, the speed detector 5 and the bulk density meter 6;

[0085] The transmission module is used to transmit the received real-time monitoring data and fixed data to the material accounting module.

[0086] The fixed data are the length between the two laser rangefinders 4 and the height from the laser rangefinder 4 to the bottom of the belt body 1. The real-time measurement data are the running speed of the belt body 1, the material density monitored by the bulk density meter 6, and the height between the laser rangefinder 4 and the material.

[0087] Material accounting module, including:

[0088] A calculation module, used to calculate the mass of the material on the belt body 1 per unit length, the material moving time per unit length, and the instantaneous flow rate of the air cushion machine according to the output data of the signal receiver;

[0089] An integrator is used to calculate the data calculated by the calculation module and perform time integration on the calculated data to generate an output signal;

[0090] The integrator plays a core role in calculating the weight of the material on the belt body 1. It integrates the weight signal and the speed signal to obtain the instantaneous flow rate and the cumulative weight of the material. Specifically, when the material is transmitted with the belt body 1, the real-time monitored material flow rate is accumulated. At the same time, the speed detector 5 measures the speed of the belt body 1 and converts the speed signal into an electrical signal. Through the integral operation, the integrator can calculate the instantaneous flow rate of the material, that is, the weight of the material passing through per unit time, and the cumulative weight, that is, the total weight of the material passing through within a period of time, ensuring the accuracy of material measurement and the improvement of production efficiency.

[0091] An accumulator, used for storing intermediate results generated in the weight calculation of the material on the belt body 1, and accumulating the weight data of each measurement;

[0092] The main function of the accumulator in the weight calculation of the material on the belt body 1 is to store and accumulate the weight data of each measurement, so as to obtain the total weight of the material. It can perform operations such as addition, subtraction, and reading, and store the intermediate results generated by the calculation. In the process of calculating the weight of the material on the belt body 1, the accumulator is used to continuously accumulate the weight of the material measured each time. Whenever the material on the belt body 1 is added, the material accounting module is used to calculate the material mass. The calculated material mass will be transmitted to the accumulator and accumulated with the previous accumulated weight. In this way, the accumulator can update and store the total weight of the material in real time;

[0093] The accumulator eliminates the need to write the result back to memory after each measurement and then read it out for the next calculation, which not only greatly improves computing efficiency, but also enables direct storage of intermediate results, thereby increasing computing speed and helping to track changing values ​​in a loop or a series of operations, thereby simplifying the processing of multiple operations and improving the efficiency and speed of the computing system.

[0094] Computing module, including:

[0095] Calculate the material mass M on the belt body 1 per unit length using the following formula:

[0096]

[0097] Calculate the material movement time t per unit length using the following formula:

[0098]

[0099] Calculate the instantaneous flow rate Q of the air cushion machine, the calculation formula is as follows:

[0100]

[0101] Wherein, L is the length between the two sets of laser rangefinders 4, H is the height from the laser rangefinder 4 to the bottom of the air cushion machine skin, v is the running speed of the belt body 1 measured by the speed detector 5, ρ is the material density measured by the bulk density meter 6, h is the height between the laser rangefinder 4 and the material, and M is the material mass on the belt body 1 per unit length.

[0102] The calculation module further includes a detection device for monitoring the current deviation threshold state of the belt body 1, and the detection device includes:

[0103] A speed sensor is arranged on the output shaft of the driving roller 2 and is used to detect the running speed of the belt body 1;

[0104] The tension sensor is arranged at the bearing of the driving roller 2 or the redirecting roller 3 to monitor the tension change of the belt body 1 and determine whether the belt is affected by uneven force;

[0105] The eccentricity sensor is arranged at the axis of the driving roller 2 or the redirecting roller 3, and determines the eccentricity of the roller by measuring the deviation between the axis and the roller;

[0106] The strain sensor is installed at the load-bearing part of the belt body 1, especially at the tensioning point or the support wheel position of the belt body 1, to monitor the local stress and deformation of the belt, thereby reflecting the change of the belt stiffness. When the belt stiffness weakens, the belt deformation increases and it is easy to deviate;

[0107] A vibration sensor is installed in the middle, on both sides or at a supporting point of the belt body 1 to monitor the vibration amplitude and frequency of the belt in real time;

[0108] A timer, mounted on the frame of the belt body 1, for detecting the running time of the belt;

[0109] Alarm: arranged on the frame of the belt body 1;

[0110] The calculation module controls the alarm to work based on the speed sensor, the tension sensor, the eccentricity sensor, the strain sensor, the vibration sensor, and the timer, including the following steps:

[0111] Step 1: The calculation module calculates the basic deviation index of the belt body 1 based on the detection values ​​of the tension sensor, eccentricity sensor, strain sensor, vibration sensor, timer and formula (1):

[0112]

[0113] Among them, X is the basic deviation index of the belt body, t represents the time variable, which is detected by the timer (since the belt transportation process is continuous, many influencing factors change with time, so time is one of the key variables in the formula); T represents the upper limit of the time integral, that is, the time range of the formula calculation; T(t) represents the belt tension at a certain time t (the belt tension directly affects the stability of the belt. Too large or too small will increase the risk of deviation. The tension change usually changes with factors such as belt load and environmental changes and is detected by the tension sensor); E(t) represents the eccentricity of the roller on the belt body, which is detected by the eccentricity sensor (that is, the degree to which the center of the roller deviates from the center of the belt. The increase in roller eccentricity will cause the belt to be unstable during operation, thereby increasing the risk of deviation, E(t) 2 is the square term of the roller eccentricity, reflecting that the effect of eccentricity on deviation is nonlinear, that is, the greater the eccentricity, the more significant the effect); K(t) represents the stiffness of the belt body, which is detected by the strain sensor (that is, the belt's ability to resist deformation under external forces. Belts with lower stiffness are more likely to deform under load or external force, resulting in deviation. is the square root of the belt stiffness, indicating the effect of stiffness on deviation); M is the load of the material transported on the belt (when the material load is too large or unevenly distributed, the belt will become unstable, thus affecting deviation. The nonlinear effect of material load. As the load increases, the effect of material on belt deviation will gradually increase, but this effect has a gradual increase); v represents the vibration amplitude of the belt, which is detected by the vibration sensor (that is, the vibration and fluctuation caused by factors such as unevenness and uneven load during the operation of the belt. Bumping will affect the stability of the belt and increase the possibility of deviation); V max Indicates the maximum belt vibration amplitude (i.e. the maximum speed or amplitude of belt vibration, = is the second third of the bump speed, used to describe the impact of bumps on deviation. The greater the bump speed, the higher the risk of deviation); W represents the width of the belt (the belt width affects the uniform distribution of materials. Too wide or too narrow will cause uneven material flow); R min Indicates the minimum roughness of the belt surface (i.e. the roughness of the belt surface texture. The surface roughness has a direct impact on the friction coefficient and the adhesion of the material); It is the combined effect of belt width and roughness, reflecting the complexity of material movement on the belt. The relative relationship between the two determines another important factor of belt stability;

[0114] Step 2: The calculation module calculates the nonlinear correction coefficient of the belt body 1 offset based on the detection value of the speed sensor and formula (2):

[0115]

[0116] Among them, Y is the nonlinear correction coefficient of the belt body offset, and D is the belt wear coefficient (with the increase of use time, the surface of the belt will wear, the friction force may change, affecting the stability of the belt, is the nonlinear effect of belt wear. When the degree of wear increases, the increase in the effect gradually slows down); R avg Indicates the average value of the belt surface roughness (the roughness directly affects the friction between the material and the belt. Too much roughness will cause the material to be unevenly distributed, increasing the risk of deviation. The effect of roughness on deviation is a square relationship, so the square of it is taken to reflect this effect); v Indicates the running speed of the belt, which is detected by the speed sensor (i.e. the speed change of the belt during operation. The speed fluctuation may cause uneven distribution of materials, thereby increasing the risk of deviation); s max Indicates the maximum speed of the belt (i.e. the maximum running speed the belt can withstand), sin(s v (t)) The periodic effect of speed fluctuation is represented by a sine function, which indicates that the speed change of the belt has periodic fluctuations, which will affect the material flow and belt stability; Indicates the ratio of the current speed to the maximum speed, which helps to measure whether the belt is close to the limit state during operation, so as to determine whether there is a risk of deviation;

[0117] Step 3: The calculation module calculates the deviation index of the belt in the belt body 1 by formula (3) based on formula (1) and formula (2):

[0118] Δ=X Y (three)

[0119] Step 4: The calculation module compares the deviation index of the belt in the belt body 1 with the preset deviation index. When the deviation index of the belt in the belt body 1 is greater than the preset deviation index, the calculation module controls the alarm to issue an alarm prompt.

[0120] The working principle and beneficial effects of the above scheme are as follows: Belt deviation refers to the deviation of the belt from the normal track due to external environment, equipment problems or improper operation during the belt transportation process. This will not only affect the stable transportation of materials, but also cause errors in the measurement results of laser rangefinders and other sensors, resulting in inaccurate material weighing. In severe cases, deviation will also damage other parts of the belt conveyor and increase maintenance costs.

[0121] Therefore, timely detection and correction of belt deviation is crucial to ensure the normal operation and accurate weighing of the air cushion machine. To achieve this, the above scheme is used to quantify and predict the possibility of belt deviation, and an alarm is issued when it exceeds the safety threshold to remind the operator to intervene.

[0122] The above solution first captures the key factors affecting belt deviation from a physical perspective, such as belt tension, roller eccentricity, belt stiffness, material load, belt bumps and width changes.

[0123] Among them, belt tension T(t): The tension of the belt is the key factor to maintain the stability of the belt. If the tension is too large or too small, it may cause the belt to deform or slip, and then cause deviation. The integral term in the formula This indicates the effect of belt tension on belt deviation over time. This means we can monitor belt tension fluctuations in real time and quantify their effect to determine if there is a risk of belt deviation.

[0124] Roller eccentricity E(t): The operation of the belt depends on the normal operation of the roller. If the eccentricity of the roller is too large, the belt will run along an unstable track. The term E(t) in the formula 2 It shows the effect of eccentricity on belt deviation. When the eccentricity increases, the risk of deviation increases sharply.

[0125] Belt stiffness K(t): Changes in belt stiffness will affect the elasticity and load-bearing capacity of the belt, thus affecting the object.

[0126] The stability of material transportation is affected. We can quantitatively calculate the effect of stiffness on belt stability.

[0127] Material load (M): If the material load is uneven, it may cause greater pressure on one side of the belt, causing deviation. The formula item takes into account the risk of deviation caused by uneven material distribution as the material load increases.

[0128] The combined effect of these physical factors can be monitored in real time through formula (1), helping operators to promptly detect abnormal belt conditions and make corresponding adjustments. For example, if the belt tension is too high or the material load is too heavy, the formula will give a predicted value and indicate whether the safety threshold has been reached.

[0129] In addition to direct physical factors, the operation of the belt is also affected by the external environment, especially factors such as belt speed and belt wear.

[0130] Belt wear (D): As the belt is used for a long time, it will wear out, which may cause changes in the friction of the belt surface, thus affecting its stability. Formula 2 can simulate the incremental impact of wear and tear and help identify potential problems caused by wear and tear in advance.

[0131] Belt speed fluctuations v (t): Belt speed fluctuation is also an important factor causing deviation. Especially under high load conditions, drastic speed fluctuations can lead to uneven material distribution, which in turn exacerbates deviation. v (t)), the effect of this periodic fluctuation on the belt stability can be quantified.

[0132] All these factors are taken into account in the formula to obtain a comprehensive belt deviation index (Δ). When the index is greater than the preset deviation index, the system will immediately sound an alarm to remind the staff to take measures such as adjusting the belt tension, checking the eccentricity of the roller, reducing the material load or correcting the environmental conditions.

[0133] Assume that a certain material is being transported by an air cushion machine. The laser rangefinder, speed sensor and bulk density meter monitor the weight, density and speed of the material in real time. In this process, factors such as belt tension, roller eccentricity and temperature all affect the stability of the belt. With the above solution, the system can evaluate at any time whether the belt deviates from the normal operating track.

[0134] For example, when the belt tension increases, the system calculates the risk of deviation through the tension part of the formula and issues an alarm.

[0135] When the belt surface roughness (R avg ) increases, the friction coefficient may also change accordingly. The system will make adjustments through a nonlinear correction formula to predict whether deviation will occur due to uneven friction.

[0136] If the material load is uneven, the terms in the formula will give the risk of deviation based on the change in load, prompting the operator to take measures to adjust the material flow.

[0137] By combining the above scheme with actual application scenarios, the intelligent laser flow scale system can not only accurately predict the risk of belt deviation, but also provide timely intervention suggestions to avoid weighing errors, equipment damage and reduced production efficiency caused by deviation. The system can significantly improve the working accuracy, stability and production efficiency of the air cushion machine by comprehensively monitoring various variables and calculating the real-time deviation index using physical and nonlinear correction formulas.

[0138] Preferably, during the material transmission process, in order to detect the stability of material transmission, a controller is provided on the outside of the hopper 8, and the controller is electrically connected to the discharge valve 7 to control the opening and closing of the discharge valve 7 and the opening and closing degree of the valve plate;

[0139] The bulk density meter 6 is electrically connected to the controller, and the bulk density meter 6 detects the material density above the belt body 1 in real time, and synchronizes the detected material density value to the controller in real time;

[0140] The laser rangefinder 4 is electrically connected to the controller. The two laser rangefinders 4 detect the distance value to the upper surface of the material in real time, and calculate the real-time thickness of the material based on the height from the laser rangefinder 4 to the bottom of the air cushion skin, and synchronize the detected real-time thickness value of the material to the controller;

[0141] The controller counts multiple material density values ​​and real-time material thickness values ​​within a unit time, and counts fluctuations in the material density values ​​and real-time material thickness values. When the fluctuation is greater than a preset fluctuation range, it is determined that there is a blockage at the opening and closing of the material plate of the discharge valve 7, and the controller controls the opening and closing degree of the material plate of the discharge valve 7 to reciprocate and adjust the opening and closing degree of the material plate of the discharge valve 7 to first increase and then retract.

[0142] The rule of reciprocating adjustment is that the opening and closing degree of the material plate increases by 10% from the initial position to the first position, then increases by 20% to the second position, then retracts from the second position to the first position, and then retracts from the first position to the initial position. The time interval of a reciprocating adjustment cycle is 3 to 5 minutes. After one interval of the reciprocating cycle, the fluctuation of the material density value and the real-time thickness value of the material is re-measured;

[0143] When the fluctuation of the material density value and the real-time thickness value measured again is within the preset range, the controller controls the material plate of the discharge valve 7 to stop moving, otherwise repeats the previous adjustment until the fluctuation of the material density value and the real-time thickness value of the material is within the preset range.

[0144] The principle and effect of the above technical solution is that by detecting the material density value and the real-time thickness value of the material in real time over a period of time, the running condition of the material on the belt body 1 after falling from the hopper 8 can be grasped. If the fluctuations of the material density value and the real-time thickness value of the material are relatively large, it means that the material falling from the hopper 8 may be stuck. The main reason for the jam of the material falling is that there is a blockage at the opening and closing of the material plate of the discharge valve 7. At this time, it is necessary to adjust the opening and closing degree of the material plate of the discharge valve 7 to solve the jam or blockage. The controller can control the opening and closing degree of the discharge valve 7. In the case of jam, it is necessary to first increase the opening and closing degree of the valve plate of the discharge valve 7 to increase the chance of material falling and make the blocked position unblocked. Therefore, it is necessary to increase the opening and closing degree of the material plate first, and gradually increase the process. The material blockage will be unblocked during the process, and then the opening and closing of the material plate will gradually return to the initial position after unblocking. After a round of cyclic adjustment, the fluctuation of the material density value and the real-time thickness value of the material will be re-detected. If the fluctuation returns to the normal range, it means that the blockage has been resolved. If it still has not returned to the normal range, it means that further adjustments are needed to resolve the blockage of the material plate. The opening and closing size of the material plate of the discharge valve 7 is readjusted until the requirements are met. On the one hand, this method has a high degree of intelligence and can detect and adjust the blockage of the material during the transmission process. On the other hand, the controller controls the opening and closing size of the material plate of the discharge valve 7 to resolve the blockage by itself. It can be resolved without stopping the machine operation, and the operation is convenient and reliable.

[0145] The present invention also discloses a method for realizing an intelligent laser flowmeter for an air cushion machine, which is applied in an intelligent laser flowmeter for an air cushion machine, and comprises the following steps:

[0146] Step 1: Obtain the length between the two laser rangefinders 4 and the height from the laser rangefinder 4 to the bottom of the belt body 1, start the driving roller 2 to make the belt body 1 run, and use the speed detector 5 to measure the running speed of the belt body 1;

[0147] Step 2: Open the discharge valve 8 to allow the material in the hopper 7 to be transported to the belt body (1). When the material passes through the laser distance meter 4, the laser distance meter 4 is used to measure the height of the material when the belt body 1 is running. When the material is transported, the bulk density meter 6 is used to measure the density of the material;

[0148] Step 3: Calculate the mass of the material on the belt body 1 per unit length by using the length between the laser rangefinder 4 and the height from the laser rangefinder 4 to the bottom of the belt body 1, the height of the material when the belt body 1 is running, the running speed of the belt body 1, the density of the material, and the height between the laser rangefinder 4 and the material;

[0149] Step 4: Calculate the material moving time per unit length using the length between the two sets of laser rangefinders 4 and the running speed of the belt body 1 measured by the speed detector 5;

[0150] Step 5: Calculate the instantaneous flow rate of the air cushion machine by using the material moving time per unit length and the material mass on the belt body 1 per unit length.

[0151] By using the laser rangefinder 4, the speed detector 5 and the bulk density meter 6 to weigh the materials on the air cushion machine, non-contact, high-precision and real-time weight measurement can be achieved, while improving the measurement efficiency and accuracy. The laser rangefinder 4 uses the time delay or phase difference of the laser beam to determine the distance, and has the advantages of high precision, fast speed and easy operation. In the weighing of the materials on the air cushion machine, the laser rangefinder 4 can measure the volume or volume change of the material, calculate the volume of the material by measuring the distance of multiple points, and then combine the density of the material to obtain the weight of the material. The speed detector 5 can monitor the movement speed of the material on the air cushion machine in real time, and the speed information can be used to In order to more accurately calculate the weight change of the material within a specific time and improve the dynamic accuracy of weighing, the bulk density meter 6 is used to measure the density of the material. The accurate density information combined with the volume measured by the laser rangefinder 4 can accurately calculate the weight of the material. The non-contact measurement avoids direct contact with the material and reduces interference and errors in the measurement process. The high-precision measurement of the laser rangefinder 4 and the speed detector 5, as well as the accurate density information provided by the bulk density meter 6, jointly ensure the accuracy and real-time nature of weighing. Compared with traditional manual measurement or single instrument measurement, this combined measurement method can greatly improve measurement efficiency and reduce measurement time.

[0152] The laser distance meter 4 is used to measure the material height when the belt body 1 is running, specifically including:

[0153] Use the laser rangefinder 4 to emit a laser beam to the surface of the material and receive the reflected laser signal;

[0154] By measuring the running time of the laser beam, the distance from the material surface to the laser rangefinder 4 is calculated, and then the material height when the belt body 1 is running is obtained.

[0155] In summary, the intelligent laser flow scale for air cushion machine and its implementation method of the present invention have simple scale structure and small installation workload. In terms of installation, it is only necessary to fix the laser rangefinder 4 on the bracket below the air cushion machine cover plate. It is not necessary to install various pressure sensors under the upper belt like ordinary belt scales and remove the belt machine body. Ordinary belt scales are affected by factors such as belt bumps, overload, roller eccentricity, belt tension changes and stiffness changes, and the pressure sensor used has a device accuracy that is greatly affected by the ambient temperature and is not suitable for working in high temperature, dusty, and highly corrosive places. The laser flow scale of the present design has no other factors except belt deviation. It does not affect the measurement. In addition, the accuracy of the laser flow scale is weaker than that of the ordinary flow scale, but its stability is higher. This flow scale needs to be simulated and calibrated with a calibration board every month according to the calibration cycle. It requires less maintenance than an ordinary belt scale, and does not require on-site configuration of weights and other accessories. This flow scale can generally maintain its initial accuracy when the air cushion machine is in poor operating condition and there is almost no maintenance. Except for the dust accumulation on the laser rangefinder 4 under the belt that affects the accuracy, the rest of the parts do not require frequent maintenance. Ordinary belt scales cannot be used on air cushion machines, but this flow scale can be used on various types of belt conveyors and has wide practicality.

[0156] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0157] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that many changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the invention.

Claims

1. An intelligent laser flowmeter for an air cushion machine, comprising a belt body (1), a driving roller (2) and a redirecting roller (3), characterized in that: The two ends of the belt body (1) are respectively provided with a driving roller (2) and a redirecting roller (3), a speed detector (5) is installed on the redirecting roller (3), a laser rangefinder (4) is installed above the belt body (1), two groups of laser rangefinders (4) are arranged, and they are respectively arranged at the two ends of the middle section of the air cushion machine, a bulk density meter (6) is installed at the tail of the belt body (1), and data collected by the laser rangefinder (4), the speed detector (5) and the bulk density meter (6) are all transmitted to the accounting device, and a hopper (8) is arranged above the belt body (1), and a discharge valve (7) is arranged at the discharge port of the hopper (8).

2. The intelligent laser flow scale for an air cushion machine according to claim 1, characterized in that: The accounting device comprises: A signal receiver, used for receiving and transmitting real-time monitoring data and fixed data collected by the laser rangefinder (4), the speed detector (5) and the bulk density meter (6); A material accounting module, used to calculate the material on the belt body (1) using the data transmitted by the signal receiver; The display module is used to display the calculation results and process of the material accounting module, as well as the data collected by the laser rangefinder (4), the speed detector (5) and the bulk density meter (6).

3. The intelligent laser flow scale for an air cushion machine according to claim 2, characterized in that: The signal receiver comprises: A receiving module, used for receiving real-time monitoring data and fixed data collected by a laser rangefinder (4), a speed detector (5) and a bulk density meter (6); The transmission module is used to transmit the received real-time monitoring data and fixed data to the material accounting module.

4. The intelligent laser flow scale for an air cushion machine according to claim 3, characterized in that: The fixed data are the length between the two laser rangefinders (4) and the height from the laser rangefinder (4) to the bottom of the belt body (1); the real-time measurement data are the running speed of the belt body (1), the material density monitored by the bulk density meter (6) and the height from the laser rangefinder (4) to the material.

5. The intelligent laser flow scale for an air cushion machine according to claim 4, characterized in that: The material accounting module includes: A calculation module, used to calculate the mass of the material on the belt body (1) per unit length, the material moving time per unit length, and the instantaneous flow rate of the air cushion machine according to the output data of the signal receiver; An integrator is used to calculate the data calculated by the calculation module and perform time integration on the calculated data to generate an output signal; The accumulator is used to store intermediate results generated in the weight calculation of the material on the belt body (1) and accumulate the weight data of each measurement.

6. The intelligent laser flowmeter for an air cushion machine according to claim 5, characterized in that: The computing module specifically includes: Calculate the material mass M on the belt body (1) per unit length using the following formula: Calculate the material movement time t per unit length using the following formula: Calculate the instantaneous flow rate Q of the air cushion machine, the calculation formula is as follows: Wherein, L is the length between the two sets of laser rangefinders (4), H is the height from the laser rangefinder (4) to the bottom of the air cushion machine skin, v is the running speed of the belt body (1) measured by the speed detector (5), ρ is the material density measured by the bulk density meter (6), h is the height between the laser rangefinder (4) and the material, and M is the material mass on the belt body (1) per unit length.

7. The intelligent laser flowmeter for an air cushion machine according to claim 5, characterized in that: The calculation module further comprises a detection device for monitoring the current deviation threshold state of the belt body (1), the detection device comprising: A speed sensor, arranged on the output shaft of the driving roller (2), for detecting the running speed of the belt body (1); A tension sensor is arranged at the bearing of the driving roller (2) or the redirecting roller (3) and is used to monitor the tension change of the belt body (1) and determine whether the belt is affected by uneven force; An eccentricity sensor is arranged at the axis of the driving roller (2) or the redirecting roller (3) to determine the eccentricity of the roller by measuring the deviation between the axis and the roller; The strain sensor is installed at the load-bearing part of the belt body (1), especially at the tensioning point or the support wheel position of the belt body (1), and is used to monitor the local stress and deformation of the belt, thereby reflecting the change of the belt stiffness. When the belt stiffness weakens, the belt deformation increases and it is easy to deviate. A vibration sensor is installed in the middle, on both sides or at a supporting point of the belt body (1) so as to monitor the vibration amplitude and frequency of the belt in real time; A timer, mounted on the frame of the belt body (1), for detecting the running time of the belt; Alarm: arranged on the frame of the belt body (1); The calculation module controls the alarm to work based on the speed sensor, the tension sensor, the eccentricity sensor, the strain sensor, the vibration sensor, and the timer, including the following steps: Step 1: The calculation module calculates the basic deviation index of the belt body (1) based on the detection values ​​of the tension sensor, the eccentricity sensor, the strain sensor, the vibration sensor, the timer, and the formula (1): Wherein, X is the basic deviation index of the belt body (1), t represents the time variable, which is detected by the timer; T represents the upper limit of the time integral, that is, the time range of the formula calculation; T(t) represents the belt tension at a certain time t, which is detected by the tension sensor; E(t) represents the eccentricity of the roller on the belt body (1), which is detected by the eccentricity sensor; K(t) represents the stiffness of the belt body (1), which is detected by the strain sensor; M represents the load of the material transported on the belt, v represents the vibration amplitude of the belt, which is detected by the vibration sensor; V max Indicates the maximum vibration amplitude of the belt; W indicates the width of the belt; R min Indicates the minimum roughness of the belt surface; Step 2: The calculation module calculates the nonlinear correction coefficient of the belt body (1) offset based on the detection value of the speed sensor and formula (2): Where Y is the nonlinear correction coefficient of the belt body (1) offset, D is the belt wear coefficient; R avg Indicates the average value of belt surface roughness; s v Indicates the belt running speed, which is detected by the speed sensor; s max Indicates the maximum speed of the belt; Step 3: The calculation module calculates the deviation index of the belt in the belt body (1) by formula (3) based on formula (1) and formula (2): Δ=X Y (three) Step 4: The calculation module compares the deviation index of the belt in the belt body (1) with a preset deviation index. When the deviation index of the belt in the belt body (1) is greater than the preset deviation index, the calculation module controls the alarm to issue an alarm prompt.

8. The intelligent laser flow scale for an air cushion machine according to claim 4, characterized in that: A controller is provided on the outside of the hopper (8), and the controller is electrically connected to the discharge valve (7) and is used to control the opening and closing of the discharge valve (7) and the opening and closing degree of the valve plate; The bulk density meter (6) is electrically connected to the controller, and the bulk density meter (6) detects the material density above the belt body (1) in real time, and synchronizes the detected material density value to the controller in real time; The laser rangefinder (4) is electrically connected to the controller, and the two laser rangefinders (4) detect the distance value to the upper surface of the material in real time, and calculate the real-time thickness of the material based on the height from the laser rangefinder (4) to the bottom of the air cushion machine skin, and synchronize the detected real-time thickness value of the material to the controller; The controller counts multiple material density values ​​and real-time material thickness values ​​within a unit time, and counts fluctuations in the material density values ​​and the real-time material thickness values. When the fluctuations are greater than a preset fluctuation range, it is determined that there is a blockage at the opening and closing of the material plate of the discharge valve (7). The controller controls the opening and closing degree of the material plate of the discharge valve (7) to perform a reciprocating adjustment of first increasing and then retracting; The rule of reciprocating adjustment is that the opening and closing degree of the material plate increases by 10% from the initial position to the first position, then increases by 20% to the second position, then retracts from the second position to the first position, and then retracts from the first position to the initial position. The time interval of a reciprocating adjustment cycle is 3 to 5 minutes. After one interval of the reciprocating cycle, the fluctuation of the material density value and the real-time thickness value of the material is re-measured; When the fluctuation of the material density value and the real-time thickness value measured again meets the preset range, the controller controls the material plate of the discharge valve (7) to stop moving, otherwise the previous adjustment is repeated until the fluctuation of the material density value and the real-time thickness value of the material meets the preset range.

9. A method for realizing an intelligent laser flowmeter for an air cushion machine, applied to the intelligent laser flowmeter for an air cushion machine as claimed in claim 6, characterized in that: The following steps are involved: Step 1: Obtain the length between the two laser rangefinders (4) and the height from the laser rangefinder (4) to the bottom of the belt body (1); Step 2: Use a laser rangefinder (4) to measure the height of the material when the belt body (1) is running, use a speed detector (5) to measure the running speed of the belt body (1), and use a bulk density meter (6) to measure the density of the material; Step 3: Calculate the mass of the material on the belt body (1) per unit length by using the length between the laser rangefinder (4), the height from the laser rangefinder (4) to the bottom of the belt body (1), the height of the material when the belt body (1) is running, the running speed of the belt body (1), the density of the material, and the height from the laser rangefinder (4) to the material; Step 4: Calculate the material moving time per unit length using the length between the two sets of laser distance meters (4) and the running speed of the belt body (1) measured by the speed detector (5); Step 5: Calculate the instantaneous flow rate of the air cushion machine using the material moving time per unit length and the material mass on the belt body (1) per unit length.

10. The method for realizing an intelligent laser flowmeter for an air cushion machine according to claim 9, characterized in that: The method of using a laser rangefinder (4) to measure the height of the material when the belt body (1) is running specifically includes: Using a laser rangefinder (4) to emit a laser beam to the surface of the material and receive the reflected laser signal; By measuring the running time of the laser beam, the distance from the material surface to the laser distance meter (4) is calculated, and then the material height when the belt body (1) is running is obtained.

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