Method and device for monitoring the state of a screen

Abstract

The application discloses a kind of screen state monitoring method and device, applied to battery field.The method in monitoring equipment can automatically obtain the first overall deformation variable of screen, the first center deformation variable of the center area of screen and the first vibration signal of screen in the case where screen meets the condition of material accumulation detection.If target condition is detected, it can be determined that the screen is in the state of material accumulation, thereby realizing automatic monitoring whether screen is material accumulation.Based on the two parameters of first overall deformation variable and first center deformation variable, whether screen is material accumulation is monitored cooperatively, avoiding the problem of misjudgment that local shape is identified as material accumulation, improving the accuracy of material accumulation detection.And in the case where deformation variable and vibration signal are used to detect whether screen is material accumulation, through the cooperative monitoring of two dimensions of deformation variable and vibration signal, the accuracy of material accumulation determination is further improved.

Description

Technical Field

[0001] This application relates to the field of batteries, specifically to a method and apparatus for monitoring the state of a screen. Background Technology

[0002] Screens are widely used in the screening and grading process of lithium battery cathode materials to ensure the uniformity and consistency of the cathode materials, thereby improving the performance and lifespan of lithium batteries and ensuring product quality.

[0003] During the production process, the screen continuously sieves materials, causing them to accumulate on the screen and form deposits. However, current technology cannot effectively detect whether material accumulation has occurred on the screen. Summary of the Invention

[0004] This invention provides a method and apparatus for monitoring the state of a screen, which can effectively detect whether material accumulation occurs on the screen. The technical solution includes: On the one hand, a method for monitoring the state of a screen is provided, the method including: Under the condition that the screen meets the material accumulation detection conditions, the first overall deformation of the screen, the first central deformation of the central region of the screen, and the first vibration signal of the screen are obtained. If the target condition is detected, it is determined that the screen is in a material accumulation state; The target conditions include at least one of the following: The first overall shape variable is greater than or equal to the first shape variable threshold, and the first central shape variable is greater than or equal to the second shape variable threshold; The frequency of the first vibration signal is less than or equal to the first frequency threshold, and the total harmonic distortion of the first vibration signal is greater than the harmonic distortion threshold.

[0005] Optionally, obtain the first overall deformation of the screen, including: Obtain the edge deformation of multiple edge regions of the screen; The first central shape variable and multiple marginal shape variables are weighted to obtain the first overall shape variable.

[0006] Optionally, the weight of the central region is greater than the weight of each edge region.

[0007] Optionally, the method also includes: Based on at least two second overall deformations of the sieve, obtain the rate of change of the first deformation; Based on at least two second vibration signals from the screen, the first frequency change rate is obtained; If the first deformation rate of change is greater than the deformation rate of change threshold and the first frequency rate of change is less than the frequency rate of change threshold, then the screen is determined to meet the material accumulation detection conditions.

[0008] Optionally, if the screen meets the conditions for material accumulation detection, the method further includes: Reduce the material feeding frequency to the first parameter threshold; Acquiring the first overall deformation of the screen, the first central deformation of the central region of the screen, and the first vibration signal of the screen, including: After the feeding frequency is reduced for a period of time until the first duration is reached, if the screen still meets the material accumulation detection conditions, the first overall deformation of the screen, the first central deformation of the central area of ​​the screen, and the first vibration signal of the screen are obtained.

[0009] Optionally, after determining that the screen is in a state of material accumulation, the method further includes: Reduce the material feeding frequency to the second parameter threshold; If the rate of decrease of the third overall deformation of the screen is less than the rate threshold when the screen changes from a state of material accumulation to a state of no material accumulation, the feeding frequency of the material should be increased.

[0010] Optionally, after increasing the feeding frequency of the material, the method further includes: After increasing the feeding frequency for a period of time until the second duration is reached, if the second central shape variable of the central region is greater than or equal to the second shape variable threshold, then the feeding frequency of the material is reduced.

[0011] Optionally, the method also includes: In response to the threshold parameter acquisition instruction, when the screen does not meet the material accumulation detection conditions, the rate of change of the second deformation is obtained based on at least two fourth overall deformations of the screen. The second frequency change rate is obtained based on at least two third vibration signals from the screen. Obtain the material type that matches the second deformation rate and the second frequency rate; Obtain the threshold parameter that matches the material type; The threshold parameters include at least one of the following: a first deformation threshold, a second deformation threshold, a first frequency threshold, and a harmonic distortion threshold.

[0012] Optional, the target conditions may also include: The transducer temperature is greater than the first temperature threshold. The current of the vibratory motor is greater than the current threshold.

[0013] On the other hand, a computer-readable storage medium is provided that stores a computer program thereon, which, when executed by a processor, implements the screen state monitoring method described above.

[0014] In another aspect, a monitoring device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the screen state monitoring method described above.

[0015] Furthermore, a screen condition monitoring device is provided, the device comprising: The acquisition module is used to acquire the first overall deformation of the screen, the first central deformation of the central region of the screen, and the first vibration signal of the screen, when it is determined that the screen meets the material accumulation detection conditions. The determination module is used to determine if the screen is in a material accumulation state if the target condition is detected. The target conditions include at least one of the following: The first overall shape variable is greater than or equal to the first shape variable threshold, and the first central shape variable is greater than or equal to the second shape variable threshold; The frequency of the first vibration signal is less than or equal to the first frequency threshold, and the total harmonic distortion of the first vibration signal is greater than the harmonic distortion threshold.

[0016] In summary, this application provides a method and apparatus for monitoring the state of a screen. In this method, when the monitoring device determines that the screen meets the material accumulation detection conditions, it can automatically acquire the first overall deformation of the screen, the first central deformation of the central region of the screen, and the first vibration signal of the screen. If the target condition is detected, it can be determined that the screen is in a material accumulation state, thereby achieving automatic monitoring of whether the screen is accumulating material.

[0017] By collaboratively monitoring both the first overall deformation and the first central deformation parameters to determine if material is accumulating on the screen, the problem of misidentifying local deformation as material accumulation is avoided, thus improving the accuracy of material accumulation detection. Furthermore, when using both deformation and vibration signals to detect material accumulation on the screen simultaneously, the collaborative monitoring of these two dimensions further enhances the accuracy of material accumulation determination.

[0018] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a material screening device provided in an embodiment of this application; Figure 2 This is a flowchart of a screen status monitoring method provided in an embodiment of this application; Figure 3 This is a flowchart of another screen status monitoring method provided in the embodiments of this application; Figure 4This is a schematic diagram of the structure of a monitoring device provided in an embodiment of this application; Figure 5 This is a block diagram of a screen condition monitoring device provided in an embodiment of this application; Figure 6 This is a block diagram of another screen status monitoring device provided in the embodiments of this application. Detailed Implementation

[0020] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0021] Screens are widely used in the screening and grading process of lithium battery cathode materials to ensure the uniformity and consistency of the cathode materials, thereby improving the performance and lifespan of lithium batteries and ensuring product quality.

[0022] The functions of a sieve include: First, grading: separating cathode materials of different particle sizes to ensure the uniformity and consistency of the cathode materials. Second, impurity removal: removing dust, impurities, and other fine particles from the material to ensure the purity of the cathode materials. This helps ensure uniform particle size of the cathode materials, improving their electrochemical performance and cycle life.

[0023] The applicant of this application discovered that during the process of material passing through a screen, the material accumulates on the screen due to differences in moisture content, particle size, and flowability, forming material buildup. Furthermore, the continuous screening of material during production also causes material to accumulate on the screen, eventually leading to screen breakage and product quality issues. However, current technologies cannot detect material accumulation on the screen in real time. The material may include cathode materials.

[0024] Figure 1 This is a schematic diagram of the structure of a material screening device provided in an embodiment of this application, as shown below. Figure 1 As shown, the screening equipment may include a raw material silo 11, a pneumatic gate valve 12, a variable frequency screw feeder 13, a vibrating screen 14, a screen mesh 141, a discharge port 15, a finished product silo 16, and multiple displacement sensors. Figure 1 (Not shown), vibration signal acquisition component 17, current monitoring component ( Figure 1 (Not shown), transducer 18 and vibration motor 19.

[0025] The main principle of the screening equipment is to separate materials of different particle sizes through vibrating screening technology. The raw material silo 11 stores the materials to be screened, and the pneumatic gate valve 12 controls whether the materials enter the variable frequency screw feeder 13, which then conveys the materials to the vibrating screen 14. The screen mesh 141 in the vibrating screen 14 is used to screen the materials, and the qualified materials are conveyed to the finished product silo 16 through the discharge port 15.

[0026] In this embodiment, all displacement sensors can be laser displacement sensors, each with a resolution ≤0.01 mm. These sensors are distributed in the edge and center regions of the screen 141. Each sensor is used to detect the displacement of its corresponding region.

[0027] The vibration signal acquisition component 17 may include a piezoelectric sensor or an accelerometer, and the vibration signal acquisition component 17 is fitted to the mesh frame of the vibrating screen 14.

[0028] The current monitoring component is located between the pneumatic gate valve 12 and the variable frequency screw feeder 13, and is used to detect the current of the motor of the variable frequency screw feeder 13.

[0029] The transducer 18 is an ultrasonic transducer located on the mesh frame. It is used to convert electrical energy into high-frequency ultrasonic vibrations and transmit them to the screen 141 to improve screening efficiency and accuracy.

[0030] The vibrating motor 19 is used to drive the vibrating screen 14 to vibrate, so that the screen 141 in the vibrating screen 14 can screen the material.

[0031] Figure 2 This is a flowchart of a screen status monitoring method provided in an embodiment of this application, applied to monitoring equipment, such as... Figure 2 As shown, the method includes: Step 201: After determining that the screen meets the material accumulation detection conditions, obtain the first overall deformation of the screen, the first central deformation of the central region of the screen, and the first vibration signal of the screen.

[0032] When the monitoring equipment determines that the screen meets the material accumulation detection conditions, it can determine that the screen may be in a material accumulation state. Therefore, it can obtain the first overall deformation of the screen at the first moment, the first central deformation of the central area of ​​the screen, and the first vibration signal of the screen.

[0033] Step 202: If the target condition is detected, it is determined that the screen is in a material accumulation state.

[0034] If the processing equipment detects the target conditions, it can determine that the screen is in a state of material accumulation.

[0035] The target condition may include at least one of the following: The first overall shape variable is greater than or equal to the first shape variable threshold, and the first central shape variable is greater than or equal to the second shape variable threshold; The frequency of the first vibration signal is less than or equal to the first frequency threshold, and the total harmonic distortion of the first vibration signal is greater than the first harmonic distortion threshold.

[0036] Understandably, material accumulation alters the inherent vibration frequency of the screen and can cause abnormalities in its deformation (such as excessive load leading to abnormal deformation). Deformation is used to directly quantify the load on the screen in the mechanical dimension, while vibration signals are used to indirectly reflect damping changes in the vibration dimension. By using both deformation and vibration signals to collaboratively detect material accumulation on the screen, the true load and usage status of the screen can be reflected more directly and accurately. This improves the accuracy of material accumulation determination, reduces the number of ineffective start-ups and shutdowns of the screening equipment, and ensures production continuity.

[0037] Furthermore, by coordinating the monitoring of whether the screen accumulates material based on two parameters—the first overall deformation and the first central deformation of the central region—the problem of misjudging local deformation as material accumulation is avoided, thus improving the accuracy of material accumulation determination.

[0038] In summary, this application provides a method for monitoring the state of a screen. In this method, when the monitoring device determines that the screen meets the material accumulation detection conditions, it can automatically acquire the first overall deformation of the screen, the first central deformation of the central region of the screen, and the first vibration signal of the screen. If the target condition is detected, it can be determined that the screen is in a material accumulation state, thereby achieving automatic monitoring of whether the screen is accumulating material.

[0039] The target conditions may include at least one of the following: the first overall deformation is greater than or equal to the first deformation threshold, and the first central deformation is greater than or equal to the second deformation threshold; the frequency of the first vibration signal is less than or equal to the first frequency threshold, and the total harmonic distortion of the first vibration signal is greater than the first harmonic distortion threshold.

[0040] By collaboratively monitoring both the first overall deformation and the first central deformation parameters to determine if material is accumulating on the screen, the problem of misidentifying local deformation as material accumulation is avoided, thus improving the accuracy of material accumulation detection. Furthermore, when using both deformation and vibration signals to detect material accumulation on the screen simultaneously, the collaborative monitoring of these two dimensions further enhances the accuracy of material accumulation determination.

[0041] Figure 3 This is a flowchart of another screen status monitoring method provided in this application embodiment, applied to monitoring equipment, such as... Figure 3 As shown, the method may include: Step 301: Based on at least two second overall deformations of the sieve, obtain the rate of change of the first deformation.

[0042] The monitoring equipment can obtain the rate of change of the first deformation based on at least two second overall deformations of the screen. Each second overall deformation refers to the overall deformation of the screen at a corresponding second time moment, and at least two second overall deformations correspond to at least two consecutive second time moments. Each second overall deformation reflects the global load of the screen at its corresponding second time moment.

[0043] For each second overall deformation at a second time step, the monitoring device can acquire the edge deformation of each edge region of the screen at the second time step, and the center deformation of the center region at the second time step. Then, the monitoring device can perform weighted processing on the edge deformations and center deformations at multiple second time steps to obtain the second overall deformation at the second time step.

[0044] In this calculation, the weight of the central region is greater than the weight of each edge region. Assuming there are two edge regions, the weight of the central region could be 0.8, and the weight of each edge region could be 0.1. This weighting process can be weighted summation, weighted averaging, etc. The edge deformation variable can be the deformation variable of the edge region at the second time step, and the central deformation variable can be the deformation variable of the central region at the second time step.

[0045] For each of the central and peripheral regions, in one implementation of this application, the monitoring device can acquire the actual displacement of the region at a second moment through a displacement sensor in that region, and use the displacement difference between the actual displacement and the standard displacement as the deformation of the region at the second moment. The standard displacement can be the initial displacement of the region before deformation, pre-stored in the monitoring device.

[0046] In another implementation of this application, strain gauges are also provided in each region. The monitoring device can acquire the resistance of the strain gauges in each region and determine the strain based on the resistance. For each region, the monitoring device can normalize both the displacement difference and the strain in that region, and then weight the normalized displacement difference and the normalized strain to obtain the deformation of that region. This method is suitable for high-temperature dust environments. Both the normalized displacement difference and the normalized strain are within a preset value range, and the weight of the displacement difference is greater than the weight of the strain.

[0047] After acquiring the second overall deformation of the screen at at least two second time points, the monitoring equipment can acquire the rate of change of the second overall deformation between every two adjacent second time points, obtaining at least one rate of change of deformation. Each rate of change of deformation can be characterized by Δd / Δt, where Δd represents the difference in the second overall deformation between two adjacent second time points, and Δt represents the time interval between two adjacent second time points. If there is only one rate of change of deformation, this single rate of change of deformation can be used as the first rate of change of deformation. If there are multiple rates of change of deformation, the first rate of change of deformation can be determined based on these multiple rates of change of deformation.

[0048] For example, the monitoring device can use the mean of the multiple rates of change of deformation as the first rate of change of deformation. Alternatively, it can use the median of the multiple rates of change of deformation as the first rate of change of deformation.

[0049] Optionally, the weights of each region can be set manually, or the monitoring device can input the screen model into the weight prediction model to obtain the weights of each region. This method is suitable for complex screen structures, such as three-layer screens.

[0050] Step 302: Based on at least two second vibration signals from the screen, obtain the first frequency change rate.

[0051] The monitoring device can also acquire the first frequency change rate based on at least two second vibration signals from the screen. Each second vibration signal refers to the vibration signal of the screen at a corresponding second moment, and this vibration signal can be acquired by a piezoelectric sensor.

[0052] For each vibration signal at a second time moment, the monitoring device can perform a Fourier transform on the vibration signal at that second time moment to obtain a first frequency domain graph, and then use the dominant frequency in the first frequency domain graph as the frequency of the vibration signal, thereby obtaining the frequency at multiple second time moments.

[0053] The monitoring device can acquire the frequency change rate between every two adjacent second time moments, obtaining at least one frequency change rate, which can be characterized by Δf / Δt, where Δf represents the frequency difference between two adjacent second time moments. If there is only one frequency change rate, the monitoring device can use this frequency change rate as the first frequency change rate. If there are multiple frequency change rates, the monitoring device can obtain the first frequency change rate based on these multiple frequency change rates.

[0054] For example, the monitoring device can use the average of the multiple frequency change rates as the first frequency change rate. Alternatively, it can use the median of the multiple frequency change rates as the first frequency change rate.

[0055] Step 303: If the first deformation rate of change is greater than the deformation rate of change threshold and the first frequency rate of change is less than the frequency rate of change threshold, then the screen is determined to meet the material accumulation detection conditions.

[0056] After acquiring the first deformation rate of change and the first frequency rate of change, the monitoring equipment can detect whether the first deformation rate of change is greater than a deformation rate of change threshold and whether the first frequency rate of change is less than a frequency rate of change threshold. If the first deformation rate of change is greater than the deformation rate of change threshold and the first frequency rate of change is less than the frequency rate of change threshold, it can be determined that the deformation of the screen is rapidly increasing and the vibration frequency of the screen is rapidly decreasing. Therefore, it can be determined that material accumulation may occur on the screen, and thus the screen meets the material accumulation detection conditions.

[0057] If the first condition is detected, it can be determined that the screen does not meet the material accumulation detection conditions. The first condition includes at least one of the following: the first deformation change rate is less than or equal to the deformation change rate threshold; the first frequency change rate is greater than or equal to the frequency change rate threshold.

[0058] For example, the deformation rate of change threshold can be 0, and the frequency rate of change threshold can be -1 Hz / s.

[0059] Step 304: Reduce the material feeding frequency to the first parameter threshold.

[0060] Once the monitoring equipment determines that the screen meets the material accumulation detection conditions, it can reduce the material feeding frequency to a first parameter threshold. For example, the first parameter threshold could be 1 Hz.

[0061] For example, if the current feeding frequency of the material is 5Hz, the monitoring device can reduce that 5Hz by 1Hz.

[0062] Step 305: Obtain the first overall deformation of the screen, the first central deformation of the central region, and the first vibration signal of the screen.

[0063] After reducing the material feeding frequency to a first parameter threshold, the monitoring equipment can acquire the first overall deformation of the screen at a first moment, the first central deformation of the central region at a first moment, and the first vibration signal of the screen at a first moment. The first moment is later than the second moment. The first overall deformation reflects the global load of the screen at the corresponding first moment, the first central deformation can be the deformation of the central region at the first moment, and the first vibration signal can be the vibration signal of the screen at the first moment.

[0064] Optionally, if the screen still meets the material accumulation detection conditions after the feeding frequency has been reduced for a certain period of time, it can be determined that the state of the screen has not changed after the feeding frequency has been reduced, and therefore the probability of material accumulation on the screen is relatively high. The monitoring equipment can then acquire the first overall deformation of the screen, the first central deformation of the central area, and the first vibration signal of the screen to further determine whether material has accumulated on the screen.

[0065] In this embodiment, the monitoring device can acquire the edge deformation of multiple edge regions of the screen at a first moment, and perform weighted processing on the first central deformation of the central region and the edge deformation of the multiple edge regions to obtain the first overall deformation. The edge deformation can be the deformation of the edge region at the first moment. The process of acquiring the first overall deformation and determining the first overall deformation can refer to step 301 above, and will not be repeated here.

[0066] Step 306: If the target condition is detected, it is determined that the screen is in a material accumulation state.

[0067] If the monitoring equipment detects the target condition when the screen meets the material accumulation detection conditions, it can determine that the screen is in a material accumulation state. If the target condition is not detected, it can determine that the screen is not in a material accumulation state. The target condition includes at least one of the following: The first overall deformation is greater than or equal to the first deformation threshold, and the first central deformation is greater than or equal to the second deformation threshold; the frequency of the first vibration signal is less than or equal to the first frequency threshold, and the total harmonic distortion of the first vibration signal is greater than the first harmonic distortion threshold.

[0068] The second deformation threshold is less than the first deformation threshold; for example, the second deformation threshold is 0.8 × d1, where d1 is the first deformation threshold. The first overall deformation D ≥ d1, and the first central deformation ≥ 0.8 × d1. The frequency f of the first vibration signal ≤ the first frequency threshold f1, and the total harmonic distortion TH of the first vibration signal > the first harmonic distortion threshold th. For example, the first harmonic distortion threshold th can be 5%.

[0069] When the overall deformation is greater than or equal to the first deformation threshold and the central deformation is greater than or equal to the second deformation threshold, the monitoring equipment can determine that the mechanical load on the screen exceeds the limit. When the frequency of the first vibration signal is less than or equal to the first frequency threshold, the monitoring equipment can determine that the damping of the screen is abnormal. When the total harmonic distortion of the first vibration signal is greater than the first harmonic distortion threshold, the monitoring equipment can determine that the harmonic components in the vibration signal exceed the standard, and the screen vibration is abnormal.

[0070] Optionally, the monitoring device can perform a Fourier transform on the first vibration signal to obtain a second frequency domain diagram, and then use the dominant frequency in the second frequency domain diagram as the frequency of the first vibration signal, and extract the total harmonic distortion from the second frequency domain diagram.

[0071] By using both deformation and vibration signals to collaboratively determine whether material has accumulated on the screen, the problem of misjudgment based on a single parameter can be eliminated, thus improving the accuracy of material accumulation determination.

[0072] In this embodiment of the application, the target condition may further include at least one of the following: the temperature of the transducer is greater than a first temperature threshold; the current of the vibration motor is greater than a current threshold.

[0073] For example, target conditions may include: the first overall deformation is greater than or equal to a first deformation threshold, and the first central deformation is greater than or equal to a second deformation threshold; the frequency of the first vibration signal is less than or equal to a first frequency threshold, and the total harmonic distortion of the first vibration signal is greater than a first harmonic distortion threshold; the temperature of the transducer is greater than a first temperature threshold; and the current of the vibration motor is greater than a current threshold. This multi-dimensional collaborative judgment improves the accuracy of material accumulation detection.

[0074] Step 307: Reduce the material feeding frequency to the second parameter threshold.

[0075] When the monitoring equipment determines that the screen is in a state of material accumulation, it can reduce the material feeding frequency to a second parameter threshold, thereby alleviating the material accumulation on the screen. This second parameter threshold is greater than the first parameter threshold; for example, the reduced feeding frequency can be 0, meaning feeding is stopped.

[0076] Step 308: When the state of the screen changes from the material accumulation state to the non-material accumulation state, if the rate of decrease of the third overall deformation of the screen is less than the rate threshold, then the feeding frequency of the material is increased.

[0077] When the screen changes from a material-accumulating state to a non-material-accumulating state, the monitoring equipment can acquire the third overall deformation of the screen. If the rate of decrease of the third overall deformation R is less than the rate threshold R0, i.e., R < R0, the screen's elasticity is considered stable, and the material feeding frequency can be increased to improve screening efficiency. If the rate of decrease of the third overall deformation R is greater than or equal to the rate threshold R0, i.e., R ≥ R0, the screen's elasticity is considered unstable, and therefore, there is no need to adjust the material feeding frequency.

[0078] The increased feeding frequency is less than the initial frequency of the screen; for example, the increased feeding frequency can be 80% of the initial frequency. The rate threshold can be 0.05 millimeters per second (mm / s).

[0079] Assuming that after feeding stops, the screen changes from a material-accumulating state to a non-material-accumulating state, and the monitoring equipment determines that the rate of decrease of the third overall deformation of the screen is less than the rate threshold, the feeding frequency of the material can be increased, for example, by restarting feeding at 80% of the initial frequency.

[0080] In this embodiment of the application, after reducing the feeding frequency of the material to the second parameter threshold, if the material accumulation release condition is detected, it can be determined that the state of the screen changes from the material accumulation state to the non-material accumulation state.

[0081] The conditions for releasing accumulated material may include at least one of the following: The current overall deformation of the screen is less than the third deformation threshold; The frequency of the vibration signal is within the preset frequency range; The total harmonic distortion of the vibration signal is less than or equal to the first harmonic distortion threshold.

[0082] Among them, the threshold of the third shape variable is less than the threshold of the first shape variable, and the lower limit within the preset frequency range is greater than the threshold of the first frequency.

[0083] Step 309: If the second central shape variable of the central region is greater than or equal to the second shape variable threshold, then reduce the feeding frequency of the material.

[0084] After increasing the feeding frequency for a second duration, the monitoring device can acquire the second central shape variable of the central region at a third time point. Since the third time point is later than the first time point, this second central shape variable is the central shape variable of the central region at the third time point. If the second central shape variable of the central region is greater than or equal to the second shape variable threshold (e.g., 0.8 × d1), it can be determined that the probability of material accumulation on the screen is relatively high. Therefore, the feeding frequency can be reduced to avoid secondary material accumulation and extend the screen's lifespan. For example, the monitoring device can reduce the feeding frequency to 60% of the initial frequency. If the second central shape variable of the central region is less than the second shape variable threshold, it can be determined that the possibility of material accumulation on the screen is low. Therefore, there is no need to adjust the feeding frequency, or the feeding frequency can be appropriately increased until it is restored to the initial frequency.

[0085] In this embodiment of the application, when the first deformation change rate is less than the deformation change rate threshold and the first frequency change rate is within the change rate threshold range, the monitoring device can increase the material feeding frequency to improve screening efficiency.

[0086] When the first rate of change of deformation is less than the threshold value, the monitoring equipment can determine that the deformation of the screen is small. When the first rate of change of frequency is within the threshold range, the monitoring equipment can determine that the damping of the screen is normal, and the vibration frequency of the screen is stable.

[0087] The lower limit of the rate of change threshold range is greater than or equal to the frequency rate of change threshold. For example, the rate of change threshold range can be [-0.5Hz / s, 0.5Hz / s].

[0088] If the first deformation rate of change is less than the deformation rate of change threshold and the first frequency rate of change is within the range of the rate of change threshold, the monitoring device can increase the feeding frequency according to the first step length, and after the third time length, detect whether the first deformation rate of change is still less than the deformation rate of change threshold and whether the first frequency rate of change is still within the range of the rate of change threshold.

[0089] If the first deformation rate of change is still less than the deformation rate of change threshold, and the first frequency rate of change is still within the range of the rate of change threshold, then the feeding frequency can be increased further. Otherwise, the monitoring equipment does not need to adjust the feeding frequency, thereby achieving dynamic adjustment of the feeding frequency based on the deformation of the screen and the frequency of the vibration signal, avoiding screen overload or wasted production capacity.

[0090] In one implementation, the monitoring device can use a proportional-integral-derivative (PID) controller to dynamically adjust the feeding frequency.

[0091] In some embodiments of this application, the monitoring device can, in response to a threshold parameter acquisition command, acquire a second deformation rate of change based on at least two fourth overall deformations of the screen, and acquire a second frequency rate of change based on at least two third vibration signals of the screen, when the screen does not meet the material accumulation detection conditions. It can then acquire the material type that matches the second deformation rate of change and the second frequency rate of change, and subsequently acquire a threshold parameter that matches the material type.

[0092] The threshold parameter may include at least one of the following: a first deformation threshold, a second deformation threshold, a first frequency threshold, and a first harmonic distortion threshold. The threshold parameter may also include all other thresholds used in the above steps.

[0093] Optionally, the monitoring device may, in response to a threshold parameter acquisition command, acquire a second deformation rate of change based on at least two fourth overall deformations of the screen, and acquire a second frequency rate of change based on at least two third vibration signals of the screen, when the screen does not meet the material accumulation detection conditions and the feeding frequency is the initial frequency.

[0094] The material type can be adaptively determined by the deformation of the screen and the frequency of the vibration signal, and then the threshold parameter corresponding to the material type can be obtained. Therefore, in the case of multiple material switching, there is no need to manually set the threshold parameter, which shortens the parameter adjustment time in the case of multiple material alternating screening and reduces labor costs.

[0095] For example, if the second deformation change rate is <0.1 mm / s and the second frequency change rate is <0.3 Hz / s, the monitoring device can determine that the material is a low-viscosity dry material.

[0096] When the second deformation rate is less than 0.2 mm / s and the second frequency rate is less than 0.3 Hz / s, the monitoring equipment can determine that the material is a medium-viscosity wet material.

[0097] When the second deformation rate is less than or equal to 0.2 mm / s and the second frequency rate is less than or equal to 0.6 Hz / s, the monitoring equipment can determine that the material is a highly viscous agglomerate.

[0098] If the material is determined to be a high-viscosity agglomerate, the first parameter threshold can be 1.5 Hz. If the rate of decrease R of the third overall deformation is less than the rate threshold R0, then increasing the material feeding frequency can result in an increased feeding frequency of 70% of the initial frequency. Furthermore, compared to the deformation change rate threshold corresponding to medium-viscosity wet materials, the deformation change rate threshold corresponding to high-viscosity materials decreases by 10%-15%.

[0099] In some embodiments of this application, if a second condition is detected, the monitoring device can determine that the screen is damaged, wherein the damage is caused by uneven deformation due to crack propagation or abnormal vibration.

[0100] The second condition may include at least one of the following: the overall deformation of the screen undergoes a sudden change within the fourth time period; the total harmonic distortion of the screen's vibration signal is greater than the second harmonic distortion threshold.

[0101] For example, the fourth duration can be 1 second. If the overall deformation of the screen increases by more than or equal to 1 mm within 1 second, the monitoring device can determine that the overall deformation of the screen has changed abruptly within 1 second. The second harmonic distortion threshold can be 8%.

[0102] If the standard deviation of the vibration signal frequency is greater than a standard deviation threshold, the monitoring equipment can determine that the vibration signal frequency is fluctuating continuously, and therefore can determine whether the screen is loose or the material is stuck. For example, the standard deviation threshold could be 2 Hz.

[0103] In some embodiments of this application, if the temperature of the transducer is greater than a first temperature threshold, but the overall deformation of the screen is less than the first deformation threshold, and the frequency of the vibration signal of the screen is within the normal frequency range, the monitoring device can determine that the transducer itself has malfunctioned, for example, the transducer is aging or the heat dissipation of the transducer has failed.

[0104] If the temperature of the transducer is greater than the first temperature threshold, but the overall deformation of the screen is greater than or equal to the first deformation threshold, and the frequency of the screen's vibration signal is less than or equal to the first frequency threshold, then the monitoring equipment may be experiencing a load-related fault, i.e., material accumulation causing transducer overload.

[0105] If the current of the vibratory motor is greater than the current threshold, but the overall deformation of the screen is less than the first deformation threshold, and the total harmonic distortion of the vibration signal is less than or equal to the first harmonic distortion threshold, then the monitoring equipment can determine that the vibratory motor itself has a fault, such as bearing wear or coil aging.

[0106] If the current of the vibratory motor exceeds the current threshold, but the overall deformation of the screen is greater than or equal to the first deformation threshold, and the total harmonic distortion of the vibration signal exceeds the first harmonic distortion threshold, then the monitoring equipment may be experiencing a load-related fault, i.e., material accumulation is causing the vibratory motor to overload. This allows for accurate differentiation between a fault "inherently caused" and one "related to the load," accurately pinpointing the cause of the fault and reducing the rate of incorrect repairs. Furthermore, it can provide early warnings of potential faults such as screen breakage, fatigue, or loosening, significantly reducing the risk of sudden equipment downtime and ensuring production continuity.

[0107] In some embodiments of this application, the monitoring device can upload different types of historical data to the cloud. The cloud can fit the same type of historical data sent by multiple monitoring devices, determine the preferred threshold corresponding to the historical data, and then send the determined preferred threshold to each monitoring device.

[0108] The monitoring equipment can upload hourly historical data to the cloud (avoiding high-frequency data congestion), while the cloud can send daily optimized thresholds downwards, achieving collaborative "real-time control + global optimization" and improving the stability of cluster production capacity. Furthermore, a fault mode library can be established based on historical data to identify new fault characteristics. For example, using "slow increase in overall deformation and slow exceedance of total harmonic distortion" can determine localized screen blockage, allowing these new fault characteristics to be synchronized to the monitoring equipment. This leverages the commonalities of the same model of equipment across multiple workshops to improve fault resolution efficiency.

[0109] In some embodiments of this application, the monitoring device can determine the fault level of the screen and then execute a response strategy that matches the fault level.

[0110] Optionally, if a third condition is detected, the monitoring device can determine that the fault level is an emergency fault. Therefore, the monitoring device can cut off the feeding power, issue the first alarm message, and push the fault report to the terminal where the manager is located.

[0111] The fault report may include fault parameters and fault level. Fault parameters may include a third condition, etc. The third condition may include at least one of the following: the overall deformation of the screen is greater than or equal to the third deformation threshold; the frequency of the vibration signal is less than the second frequency threshold; the temperature of the transducer is greater than the second temperature threshold.

[0112] The third shape variable threshold is greater than the first shape variable threshold. For example, the third shape variable threshold is equal to 1.5 times the first shape variable threshold. The second frequency threshold is less than the first frequency threshold. The second temperature threshold is greater than the first temperature threshold; for example, the difference between the second and first temperature thresholds can be 10 degrees Celsius.

[0113] If the fourth condition is detected, the monitoring equipment can determine the fault level as a general fault. Therefore, the monitoring equipment can reduce the feeding frequency and issue a second alarm message. If the fault is not resolved within the target time, the screening equipment can be shut down. For example, the monitoring equipment can reduce the feeding frequency to 50% of the initial frequency.

[0114] The fourth condition may include at least one of the following: the overall deformation of the screen is greater than or equal to the first deformation threshold and less than the third deformation threshold; the number of times the screen accumulates material within a preset time period reaches the target number; the total harmonic distortion of the vibration signal is greater than or equal to the second harmonic distortion threshold and less than or equal to the third harmonic distortion threshold.

[0115] For example, the preset duration can be 1 hour, the target number of harmonics can be 2, and the third harmonic distortion threshold can be 10%.

[0116] If the fifth condition is detected, the monitoring equipment can determine that the fault level is a warning fault. Therefore, the monitoring equipment can issue a third alarm message and record the fault level.

[0117] The fifth condition may include: the total harmonic distortion of the vibration signal is less than the second harmonic distortion threshold and greater than or equal to the fourth harmonic distortion threshold; the standard deviation of the frequency of the vibration signal is within a preset standard deviation range; and the temperature of the transducer is less than the first temperature threshold.

[0118] For example, the fourth harmonic distortion threshold can be 6%. The preset standard deviation range has a lower limit of 2Hz and an upper limit of 3Hz.

[0119] In this embodiment, corresponding response strategies are set for different fault levels, which can reduce unnecessary downtime, significantly improve production continuity, and optimize fault diagnosis accuracy and maintenance efficiency.

[0120] This application embodiment constructs a more direct and accurate material accumulation identification and equipment protection system through dual-dimensional collaborative monitoring of screen deformation and vibration acoustic characteristics. Using the solution provided in this application embodiment, the feeding frequency can be dynamically adjusted by detecting the deformation and vibration signal frequency, achieving intelligent and significantly optimized feeding control. Furthermore, by dynamically adjusting the feeding frequency and recovery logic based on the screen deformation change rate and vibration acoustic characteristic change rate, the feeding speed is precisely matched with the screen's real-time processing capacity, improving the stability of vibrating screen production capacity, reducing the frequency of manual intervention, and lowering labor costs.

[0121] In addition, due to the reduction in material accumulation misjudgment and the improvement in feeding adaptability, the equipment's ineffective running time is shortened, reducing energy consumption compared to traditional technologies, and the energy consumption control effect is outstanding.

[0122] Furthermore, there is no need for large-scale structural modifications to existing vibrating screen equipment. Upgrades can be achieved simply by adding displacement sensors and vibration signal acquisition components. The modification cost is low, and it can be adapted to screening scenarios for various materials such as granules, powders, and lumps. It has a wide range of applications and strong system compatibility and scalability.

[0123] In summary, this application provides a method for monitoring the state of a screen. In this method, when the monitoring device determines that the screen meets the material accumulation detection conditions, it can automatically acquire the first overall deformation of the screen, the first central deformation of the central region of the screen, and the first vibration signal of the screen. If the target condition is detected, it can be determined that the screen is in a material accumulation state, thereby achieving automatic monitoring of whether the screen is accumulating material.

[0124] By collaboratively monitoring both the first overall deformation and the first central deformation parameters to determine if material is accumulating on the screen, the problem of misidentifying local deformation as material accumulation is avoided, thus improving the accuracy of material accumulation detection. Furthermore, when using both deformation and vibration signals to detect material accumulation on the screen simultaneously, the collaborative monitoring of these two dimensions further enhances the accuracy of material accumulation determination.

[0125] This application provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the screen state monitoring method described in the above embodiments.

[0126] Figure 4 This is a schematic diagram of the structure of a monitoring device provided in an embodiment of this application, as shown below. Figure 4 As shown, the monitoring device 40 includes a memory 401, a processor 402, and a computer program stored in the memory 401 and executable on the processor 402. When the processor 402 executes the computer program, it implements the screen status monitoring method described in the above embodiments.

[0127] Figure 5This is a block diagram of a screen status monitoring device provided in an embodiment of this application, such as... Figure 5 As shown, the device includes: The acquisition module 501 is used to acquire the first overall deformation of the screen, the first central deformation of the central region of the screen, and the first vibration signal of the screen when it is determined that the screen meets the material accumulation detection conditions. The determination module 502 is used to determine that the screen is in a material accumulation state if the target condition is detected; The target conditions include at least one of the following: The first overall shape variable is greater than or equal to the first shape variable threshold, and the first central shape variable is greater than or equal to the second shape variable threshold; The frequency of the first vibration signal is less than or equal to the first frequency threshold, and the total harmonic distortion of the first vibration signal is greater than the harmonic distortion threshold.

[0128] Optionally, module 501 is used for: Obtain the edge deformation of multiple edge regions of the screen; The first central shape variable and multiple marginal shape variables are weighted to obtain the first overall shape variable.

[0129] Optionally, the weight of the central region is greater than the weight of each edge region.

[0130] Optionally, module 501 is used for: Based on at least two second overall deformations of the sieve, obtain the rate of change of the first deformation; Based on at least two second vibration signals from the screen, the first frequency change rate is obtained; If the first deformation rate of change is greater than the deformation rate of change threshold and the first frequency rate of change is less than the frequency rate of change threshold, then the screen is determined to meet the material accumulation detection conditions.

[0131] Optionally, module 501 is used for: If the screen meets the material accumulation detection conditions, the material feeding frequency is reduced to the first parameter threshold. After the feeding frequency is reduced for a period of time until the first duration is reached, if the screen still meets the material accumulation detection conditions, the first overall deformation of the screen, the first central deformation of the central area of ​​the screen, and the first vibration signal of the screen are obtained.

[0132] refer to Figure 6 The device also includes an adjustment module 503 for: After determining that the screen is in a state of material accumulation, the material feeding frequency is reduced to the second parameter threshold. If the rate of decrease of the third overall deformation of the screen is less than the rate threshold when the screen changes from a state of material accumulation to a state of no material accumulation, the feeding frequency of the material should be increased.

[0133] Optionally, adjustment module 503 is also used for: After increasing the feeding frequency of the material, and after the duration of increasing the feeding frequency reaches the second duration, if the second central shape variable of the central region is greater than or equal to the second shape variable threshold, then the feeding frequency of the material is reduced.

[0134] Optionally, module 501 is used for: In response to the threshold parameter acquisition instruction, when the screen does not meet the material accumulation detection conditions, the rate of change of the second deformation is obtained based on at least two fourth overall deformations of the screen. The second frequency change rate is obtained based on at least two third vibration signals from the screen. Obtain the material type that matches the second deformation rate and the second frequency rate; Obtain the threshold parameter that matches the material type; The threshold parameters include at least one of the following: a first deformation threshold, a second deformation threshold, a first frequency threshold, and a harmonic distortion threshold.

[0135] Optional, the target conditions may also include: The transducer temperature is greater than the first temperature threshold. The current of the vibratory motor is greater than the current threshold.

[0136] In summary, this application provides a screen state monitoring device. When the screen meets the material accumulation detection conditions, the device can automatically acquire the screen's first overall deformation, the screen's first central deformation of its central region, and the screen's first vibration signal. If the target condition is detected, it can be determined that the screen is in a material accumulation state, thereby achieving automatic monitoring of whether the screen is accumulating material.

[0137] By collaboratively monitoring both the first overall deformation and the first central deformation parameters to determine if material is accumulating on the screen, the problem of misidentifying local deformation as material accumulation is avoided, thus improving the accuracy of material accumulation detection. Furthermore, when using both deformation and vibration signals to detect material accumulation on the screen simultaneously, the collaborative monitoring of these two dimensions further enhances the accuracy of material accumulation determination.

[0138] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0139] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0140] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0141] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0142] Furthermore, the terms "first," "second," etc., used in the embodiments of this invention are for descriptive purposes only and should not be construed as indicating or implying relative importance, or implicitly specifying the number of technical features indicated in this embodiment. Therefore, features defined with terms such as "first" and "second" in the embodiments of this invention can explicitly or implicitly indicate that the embodiment includes at least one of those features. In the description of this invention, the word "multiple" means at least two or more, such as two, three, four, etc., unless otherwise explicitly specified in the embodiments.

[0143] In this invention, unless otherwise explicitly specified or limited in the embodiments, the terms "installation," "connection," "joining," and "fixing" appearing in the embodiments should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral part; it can also be a mechanical connection, an electrical connection, etc. Of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components, or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific implementation.

[0144] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0145] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for monitoring the state of a screen, characterized in that, The method includes: If the screen meets the material accumulation detection conditions, the feeding frequency of the material is reduced to a first parameter threshold. After the feeding frequency is reduced for a first duration, if the screen still meets the material accumulation detection conditions, the first overall deformation of the screen, the first central deformation of the central region of the screen, and the first vibration signal of the screen are obtained. If a target condition is detected, the screen is determined to be in a material accumulation state; wherein, the target condition includes at least one of the following: the first overall deformation is greater than or equal to a first deformation threshold, and the first central deformation is greater than or equal to a second deformation threshold; the frequency of the first vibration signal is less than or equal to a first frequency threshold, and the total harmonic distortion of the first vibration signal is greater than a harmonic distortion threshold; After determining that the screen is in a material accumulation state, the method further includes: The method further includes reducing the feeding frequency of the material to a second parameter threshold, and when the state of the screen changes from the material accumulation state to the non-material accumulation state, if the rate of decrease of the third overall deformation of the screen is less than a rate threshold, then increasing the feeding frequency of the material; the method also includes: In response to the threshold parameter acquisition instruction, when the screen does not meet the material accumulation detection condition, a second deformation change rate is obtained based on at least two fourth overall deformations of the screen, and a second frequency change rate is obtained based on at least two third vibration signals of the screen. Obtain a material type that matches the second deformation rate of change and the second frequency rate of change, and obtain a threshold parameter that matches the material type; wherein the threshold parameter includes at least one of the first deformation threshold, the second deformation threshold, the first frequency threshold, and the harmonic distortion threshold.

2. The method according to claim 1, characterized in that, Obtaining the first overall deformation of the screen includes: Obtain the edge deformation of multiple edge regions of the screen; The first central shape variable and the plurality of marginal shape variables are weighted to obtain the first overall shape variable.

3. The method according to claim 2, characterized in that, The weight of the central region is greater than the weight of each of the edge regions.

4. The method according to any one of claims 1 to 3, characterized in that, The method further includes: Based on at least two second overall deformations of the sieve, the rate of change of the first deformation is obtained; Based on at least two second vibration signals from the screen, a first frequency change rate is obtained; If the first deformation rate of change is greater than the deformation rate of change threshold and the first frequency rate of change is less than the frequency rate of change threshold, then the screen is determined to meet the material accumulation detection condition.

5. The method according to claim 1, characterized in that, After increasing the feeding frequency of the material, the method further includes: After the feeding frequency is increased for a second duration, if the second central shape variable of the central region is greater than or equal to the second shape variable threshold, the feeding frequency of the material is reduced.

6. The method according to any one of claims 1 to 3, characterized in that, The target conditions also include: The transducer temperature is greater than the first temperature threshold. The current of the vibratory motor is greater than the current threshold.

7. A computer-readable storage medium, characterized in that, It stores a computer program, which, when executed by a processor, implements the screen state monitoring method according to any one of claims 1 to 6.

8. A monitoring device, characterized in that, The device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the screen state monitoring method according to any one of claims 1 to 6.

9. A device for monitoring the state of a screen, characterized in that, For implementing the screen state monitoring method according to any one of claims 1 to 6; the device comprises: The acquisition module is used to acquire the first overall deformation of the screen, the first central deformation of the central region of the screen, and the first vibration signal of the screen when it is determined that the screen meets the material accumulation detection conditions. A determination module is used to determine that the screen is in a material accumulation state if a target condition is detected; The target conditions include at least one of the following: The first overall shape variable is greater than or equal to the first shape variable threshold, and the first central shape variable is greater than or equal to the second shape variable threshold; The frequency of the first vibration signal is less than or equal to a first frequency threshold, and the total harmonic distortion of the first vibration signal is greater than the harmonic distortion threshold.

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