Dynamic stress regulation and control method of crusher in bio-fertilizer production process

Abstract

The invention relates to the technical field of bio-fertilizer crushing, and discloses a dynamic stress regulation and control method of a crusher in a bio-fertilizer production process, which comprises the following steps: arranging a non-uniform gradient microgroove array arranged according to a Fibonacci sequence on a working surface of a cutter, filling a beta-glucan-based viscoelastic composite material in the microgrooves, the grain orientation of a tool matrix is regulated and controlled through an electromagnetic field-assisted directional solidification process, and a dynamic stress wave self-interference regulation and control system is constructed. Through the synergistic effect of geometric arrangement of the microgroove array and the nonlinear damping characteristic of the viscous-elastic material, the destructive interference effect of stress waves is spontaneously formed in the crushing process, and space equalization and peak suppression of dynamic stress of the working face of the cutter are achieved; the problems of stress concentration and tool fatigue of a traditional crusher in high-fiber and high-viscosity bio-fertilizer raw material processing are fundamentally solved, the crushing efficiency is remarkably improved, and the service life of equipment is remarkably prolonged.

Description

Technical Field

[0001] The present invention relates to the field of biological fertilizer crushing, and particularly to a method for dynamically regulating the stress of a crusher during the production process of biological fertilizers. Background Art

[0002] Existing technologies generally adopt a dynamic stress regulation method that combines sensor array monitoring and multivariable feedback control. Such methods attempt to balance the impact load generated during the material crushing process by collecting tool strain signals in real time and adjusting the operating parameters of the crusher. Under normal working conditions, such methods can achieve basic stress control. However, when dealing with high-hardness materials mixed with fiber bundles and crystalline salts or highly viscous organic fertilizers containing humic acid, their inherent limitations gradually emerge. For the crushing scenario of high-fiber materials, the direct confrontation mode between traditional rigid tools and materials easily leads to the concentrated release of stress waves in the tip area, triggering the initiation of microcracks. Although existing technologies attempt to alleviate this problem by strengthening the tool material or increasing the control frequency, since the propagation path of stress waves is not actively guided, their improvement solutions can often only achieve local stress attenuation and cannot achieve global equalization distribution at the initial stage of energy conduction. When encountering sudden changes in material composition, the inherent delay between sensor signal acquisition and actuator response further exacerbates the formation of stress peaks.

[0003] During the crushing process of highly viscous organic fertilizers, the problem of stress backpropagation caused by the adhesion effect is particularly prominent. Traditional methods rely on linear control strategies for adjusting the feeding speed and tool rotation speed and are difficult to cope with the dynamic wetting effect of viscous components on the microscopic structure of the tool surface. Existing improvement solutions attempt to introduce surface coating technology, but the static protection characteristics of the coating cannot adapt to the dynamic stress fluctuations caused by viscous materials, and the interfacial bonding strength between the coating and the substrate is prone to degradation under long-term impact.

[0004] The grain orientation control process explored by the industry in recent years has, to a certain extent, improved the fatigue resistance of tool materials, but its mechanism of action is still limited to the material modification level and has not formed a synergistic optimization with the geometric structure of the tool surface. There are generally three core limitations in the existing technology system: 1. The stress regulation logic overly relies on external energy input and lacks active intervention in the spatio-temporal distribution law of energy; 2. The dynamic hysteresis effect leads to a mismatch between the system response speed and the material mutation frequency; 3. The fragmented design of microscopic structure and macroscopic control limits the intelligent reconstruction ability of the stress wave conduction path. Therefore, how to spontaneously achieve the path planning and energy dissipation of stress waves during the crushing process through the active design of tool microscopic structure and the dynamic adaptation of material properties, and thus avoid the adaptability bottleneck of traditional control methods in complex material processing scenarios, has become a key technical problem to be solved in this field. Summary of the Invention

[0005] The present invention addresses the technical problems existing in the prior art, namely, tool fatigue failure and reduced crushing efficiency caused by dynamic stress concentration during the crushing of high-fiber and highly viscous biological fertilizers, and provides a method for regulating the dynamic stress of a crusher during the production process of biological fertilizers to solve these problems.

[0006] The technical solution of the present invention to solve the above technical problems is as follows: A method for regulating the dynamic stress of a crusher during the production process of biological fertilizers, the method comprising the following steps: Step a, setting a non-uniform gradient microgroove array on the tool working surface, the microgrooves having an inclination angle gradient in the range of 5° to 25°, and the depth and spacing of the microgrooves are non-uniformly arranged along the tool working surface according to the variable ratio of the Fibonacci sequence, wherein the depth of the th microgroove is determined by the formula , is the reference depth, is the th term of the Fibonacci sequence; Step b, filling the inside of the microgrooves with a viscoelastic composite material formed by extracting β-glucan from waste edible mushroom mycelia and treating it with alkali and nano-silica to construct an interfacial layer with non-linear damping characteristics, wherein the particle size range of the nano-silica is 10 - 15 nm, and the surface is grafted with a mercapto-modified group to form a disulfide bond cross-linking network with cysteine residues in β-glucan, and the glass transition temperature of the viscoelastic composite material is set in the range of 55°C to 65°C; Step c, regulating the grain orientation of the tool substrate material through an electromagnetic field-assisted directional solidification process, such that the included angle between the long axis of the grains and the cutting force direction is less than 10°, thereby forming a low-impedance stress wave guiding path inside the tool; Step d, real-time monitoring of the working current volatility of the crusher, when exceeds the preset threshold of 10% ( is the instantaneous current value, is the moving average current value of the previous 5 minutes), start the tool cooling system to maintain the tool working temperature within the range of to ; Step e, the geometric parameters of the non-uniform gradient microgroove array, the dynamic mechanical response characteristics of the viscoelastic interfacial layer, and the grain preferred orientation of the tool substrate material together constitute a dynamic stress wave self-interference regulation system. During the crushing process of biological fertilizers, by inducing and regulating the propagation path and phase of stress waves at the microscale, promoting the destructive interference between the primary stress wave and the reflected stress wave to achieve spatial equalization and peak suppression of the dynamic stress on the tool working surface.

[0007] In a preferred embodiment, in the non-uniform arrangement of the Fibonacci sequence ratio in step a, the depth ratio of adjacent micro-grooves along with the groove sequence increasing, gradually approaches the golden ratio .

[0008] In a preferred embodiment, in step b, the mass ratio of nano-silica to β-glucan is controlled within the range of 0.8:1 to 1.2:1 to adjust the damping coefficient and phase transition temperature of the viscoelastic composite material.

[0009] In a preferred embodiment, the electromagnetic field-assisted directional solidification process in step c includes the following stages: In the first stage, an axial static magnetic field is applied, with a magnetic field strength of 1.0 T to 1.2 T and a duration of 20 to 40 minutes; in the second stage, it is switched to a radial rotating magnetic field, with a magnetic field strength of 0.4 T to 0.6 T, a rotation frequency of 1 to 3 Hz, and a duration of 10 to 20 minutes; in the third stage, an axial pulsed magnetic field is applied, with a magnetic field strength of 0.6 T to 1.0 T, a pulse frequency of 3 to 7 Hz, and a duration of 15 to 30 minutes.

[0010] In a preferred embodiment, it further includes setting an infrared spectroscopy on-line monitoring device at the feed inlet of the pulverizer to detect the humic acid content of the biological fertilizer raw material in real time. When the detected humic acid content exceeds 20%, the inclination gradient of the micro-groove array in step a is dynamically adjusted so that the inclination increases with the mass of the processed material and its variation relationship is , where is the inclination adjustment coefficient, and its value range is 0.01° / kg to 0.05° / kg.

[0011] In a preferred embodiment, the cancellation interference effect of the stress wave in step e is quantitatively evaluated through the stress balance degree index , where , and are respectively the minimum and maximum stress values on the tool working surface. When is lower than 85%, the topology optimization program of the micro-groove array is triggered.

[0012] In a preferred embodiment, the topology optimization program is based on a finite element analysis model, iteratively adjusts the depth and spacing of the micro-grooves to maximize the stress balance degree index , and after the optimization is completed, drives the laser etching device to perform in-situ repair on the tool surface, and the repair accuracy is controlled within the range of ±3 μm.

[0013] In a preferred embodiment, the dynamic storage modulus of the viscoelastic interface layer and loss modulus vary with the stress amplitude and satisfy a non-linear relationship: , where is the loss modulus under low stress, is the non-linear coefficient, which is adjusted by controlling the cross-linking density of β-glucan and nano-silica.

[0014] In a preferred embodiment, a piezoelectric sensor is further provided on the tool mounting base to collect vibration signals during the crushing process in real time, and characteristic frequencies related to specific material components are extracted through frequency domain analysis , and according to the changes of, the geometric parameters of the micro-groove array in step a are dynamically adjusted to optimize the stress wave interference effect for different bio-fertilizer raw materials.

[0015] 1. In the crushing scenario of high-hardness materials mixed with fiber bundles and crystal salts, the Fibonacci arrangement law of the non-uniform gradient micro-groove array and the non-linear damping characteristics of the viscoelastic interface layer form a spatio-temporal coupling effect. The gradient change of the micro-groove inclination angle guides the principal stress wave to form a spiral diffusion path on the tool surface, while the phase change lag effect of the viscoelastic material constructs an adaptive dissipation barrier during the impact energy conduction process. The synergistic effect of the two enables the local stress peaks caused by fiber fracture to be resolved by the dual mechanisms of geometric dispersion and material absorption at the initial stage of conduction, fundamentally avoiding the problem of microcrack initiation caused by stress concentration in traditional rigid tools.

[0016] 2. For the crushing condition of viscous organic fertilizers containing humic acid, the dynamic inclination angle adjustment mechanism of the micro-groove array and the guiding path of grain preferred orientation produce cross-scale synergy. When a sudden change in material viscosity is detected, the inclination angle gradient adjustment based on infrared spectrum feedback causes the micro-grooves to form a centrifugal arrangement pattern, forcing the adhesion stress to dissipate radially along the tool; at the same time, the grain boundary channels constructed by the directional solidification process change the anisotropy of stress wave conduction and direct the residual energy to the buffer structure of the tool mounting base; the organic combination of this macroscopic geometric regulation and microscopic grain boundary engineering effectively avoids the problem of stress backpropagation caused by tool surface crusting during the crushing of high-viscosity materials.

[0017] 3. Under complex working conditions with random fluctuations in raw material components, the dynamic stress wave self-interference regulation system exhibits a unique system-level self-optimization ability. The Fibonacci arrangement pattern of the microgroove array inherently contains the self-similar characteristics of the golden ratio, enabling it to match the stress wavelengths of different materials through the natural frequencies of the geometric structure. The linkage control between the glass transition temperature window of the viscoelastic interface layer and the cooling system of the crusher realizes the real-time adaptation of the energy dissipation path through the dynamic switching of the material phase state. The synergistic effect of the two endows the tool system with robustness against the impact of unknown materials, avoiding the limitations of traditional control methods that rely on precise modeling.

[0018] 4. The electromagnetic field-assisted directional solidification process and the closed-loop feedback mechanism of the stress balance degree index jointly construct a double guarantee for improving the anti-fatigue performance. The directional arrangement of the long axes of the grains not only reduces the stress impedance in the main cutting direction, but also suppresses the crack propagation path by reducing the number of grain boundaries due to the formation of a single-crystal-like structure. When the stress balance degree index triggers the repair threshold, the topology optimization program based on finite element analysis corrects the microgroove parameters online, enabling the tool surface to always maintain the optimal stress distribution pattern. This dynamic balance mechanism of material modification and structure optimization significantly extends the service life of the tool under high-frequency impact working conditions. Brief Description of the Drawings

[0019] Figure 1 It is a timing diagram of the stress wave regulation principle of the present invention; Figure 2 It is a schematic structural diagram of the dynamic stress regulation system of the present invention; Figure 3 It is a flowchart of the dynamic stress regulation method of the present invention. Detailed Embodiments

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present invention.

[0021] In the description of the present invention, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of the present invention, "a plurality" means two or more, unless otherwise specifically defined.

[0022] In the description of the present invention, the term "for example" is used to mean "serving as an example, illustration, or explanation". Any embodiment described as "for example" in the present invention is not necessarily to be construed as more preferred or advantageous than other embodiments. The following description is given to enable any person skilled in the art to implement and use the present invention. In the following description, details are set forth for purposes of explanation. It should be understood that those of ordinary skill in the art can recognize that the present invention can be implemented without these specific details. In other instances, well-known structures and processes are not elaborated in detail so as not to obscure the description of the present invention with unnecessary details. Therefore, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

[0023] A method for dynamically regulating the stress of a crusher during the production process of a biological fertilizer, the method comprising the following steps: Step a, setting a non-uniform gradient micro-groove array on the working surface of the cutting tool, the micro-grooves having an inclination gradient ranging from 5° to 25°, and the depth of the micro-grooves and the spacing are non-uniformly arranged along the working surface of the cutting tool according to the variable ratio of the Fibonacci sequence, wherein the depth of the th micro-groove is determined by the formula where is the reference depth, is the th term of the Fibonacci sequence; Step b, filling the inside of the micro-grooves with a viscoelastic composite material formed by extracting β-glucan from waste edible mushroom mycelium and treating it with alkali and nano-silica to construct an interface layer with non-linear damping characteristics, wherein the particle size range of the nano-silica is 10-15 nm, and the surface is grafted with a mercapto-modified group to form a disulfide bond cross-linking network with cysteine residues in β-glucan, and the glass transition temperature of the viscoelastic composite material is set in the range of 55°C to 65°C; Step c, regulating the grain orientation of the cutting tool substrate material through an electromagnetic field-assisted directional solidification process, such that the included angle between the major axis of the grains and the cutting force direction is less than 10°, thereby forming a low-impedance stress wave guiding path inside the cutting tool; Step d, real-time monitoring of the working current volatility of the crusher, and when exceeds the preset threshold of 10% (where is the instantaneous current value and is the moving average current value in the previous 5 minutes), start the cutting tool cooling system to maintain the working temperature of the cutting tool within the range of to ; Step e: The geometric parameters of the non-uniform gradient microgroove array, the dynamic mechanical response characteristics of the viscoelastic interface layer, and the grain preferred orientation of the tool substrate material jointly constitute a dynamic stress wave self-interference regulation system. During the pulverization process of the biological fertilizer, by inducing and regulating the propagation path and phase of the stress wave at the microscale, the destructive interference between the primary stress wave and the reflected stress wave is promoted to achieve spatial equalization and peak suppression of the dynamic stress on the tool working surface.

[0024] In a preferred embodiment, in the non-uniform arrangement with the Fibonacci sequence ratio change in step a, the depth ratio of adjacent microgrooves along with the groove sequence increasing, gradually approaches the golden ratio .

[0025] In a preferred embodiment, in step b, the mass ratio of nano-silica to β-glucan is controlled within the range of 0.8:1 to 1.2:1 to adjust the damping coefficient and phase transition temperature of the viscoelastic composite material.

[0026] In a preferred embodiment, in step c, the electromagnetic field-assisted directional solidification process includes the following stages: In the first stage, an axial static magnetic field is applied, with a magnetic field strength of 1.0 T to 1.2 T and a duration of 20 to 40 minutes; in the second stage, it is switched to a radial rotating magnetic field, with a magnetic field strength of 0.4 T to 0.6 T, a rotation frequency of 1 to 3 Hz, and a duration of 10 to 20 minutes; in the third stage, an axial pulsed magnetic field is applied, with a magnetic field strength of 0.6 T to 1.0 T, a pulse frequency of 3 to 7 Hz, and a duration of 15 to 30 minutes.

[0027] In a preferred embodiment, it further includes setting an infrared spectroscopy on-line monitoring device at the feed inlet of the pulverizer to real-time detect the humic acid content of the biological fertilizer raw material. When the detected humic acid content exceeds 20%, the inclination gradient of the microgroove array in step a is dynamically adjusted, such that the inclination increases with the mass of the processed material, and its variation relationship is , where is the inclination adjustment coefficient, and its value range is 0.01° / kg to 0.05° / kg.

[0028] In a preferred embodiment, in step e, the destructive interference effect of the stress wave is quantitatively evaluated through the stress equalization degree index , , where and are respectively the minimum and maximum stress values on the tool working surface. When is lower than 85%, the topological optimization program of the microgroove array is triggered.

[0029] In a preferred embodiment, the topology optimization program is based on a finite element analysis model and iteratively adjusts the depth and spacing of the micro-grooves to maximize the stress equilibrium degree index. After the optimization is completed, it drives a laser etching device to perform in-situ repair on the tool surface, and the repair accuracy is controlled within the range of ±3 μm.

[0030] In a preferred embodiment, the dynamic storage modulus of the viscoelastic interface layer and the loss modulus vary with the stress amplitude to satisfy a non-linear relationship: where is the loss modulus under low stress, is the non-linear coefficient, which is adjusted by controlling the cross-linking density of β-glucan and nano-silica.

[0031] In a preferred embodiment, it further includes setting a piezoelectric sensor on the tool mounting base to collect vibration signals during the crushing process in real time, extracting characteristic frequencies related to specific material components through frequency domain analysis and dynamically adjusting the geometric parameters of the micro-groove array in step a according to the change to optimize the stress wave interference effect for different raw materials of biological fertilizers.

[0032] In addition, in the embodiments of the present invention, to further verify the influence of grain preferred orientation on stress wave guiding behavior, a microscopic grain finite element model of the tool substrate material was constructed. Comparative simulations were carried out with different angles (θ) between the major axis of the grain and the cutting force direction (5°, 15°, and 30° respectively). The results show that when the angle is less than 10°, the effective velocity of the primary stress wave propagating along the major axis of the grain is increased by about 22% compared with the random orientation, and the wave impedance uniformity index is increased by more than about 18%. This indicates that the directionally arranged grain structure helps to form a stress channel with low scattering and high conductivity. This guiding effect plays a positive role in weakening stress concentration and improving the uniform transmission of wave energy inside the tool, verifying the synergistic relationship between the grain structure and the dynamic regulation system. To verify the spatial equalization efficiency of the dynamic stress wave self-interference regulation system under actual working conditions, the present invention uses a three-dimensional structure finite element model established based on the Abaqus platform to conduct a comparative simulation of the stress distribution on the tool working surface under the action of a typical impact load (peak value 35 MPa, pulse width 0.5 ms). The simulation comparison objects are: the surface of a traditional tool without a microgroove and viscoelastic layer structure and the surface of a composite tool using the structure of the present invention. The results show that within the same time frame, the maximum stress concentration area of the traditional structure tool is concentrated at the cutting edge, and the SEI index is about 72%; while under the tool structure of the present invention, obvious destructive interference occurs to the primary stress wave in the microgroove-induced path, the maximum stress point drops by about 16%, and the SEI increases to 91%. The simulation results fully show that the microgroove-material-guiding ternary system can achieve dynamic stress peak suppression and spatial balanced diffusion, with practical feasibility and significant benefits, which all belong to the extended implementation modes known to those of ordinary skill in the art.

[0033] Example 1: When processing a biological fertilizer raw material containing a mixture of high-fiber waste mushroom bran and partially fermented chicken manure, since this mixture contains both hyphal residues with a dense structure and strong shear resistance and a large number of humic acid groups with significant adhesiveness, traditional crusher tools are prone to serious stress concentration and stress backpropagation phenomena in a short time, resulting in increased tool wear and a significant decrease in efficiency. To address this typical complex working condition, this example combines the dynamic stress regulation mechanism proposed in the present invention and demonstrates stronger stability and adaptability in the actual application scenario.

[0034] First, under this working condition, to ensure that the stress wave forms an effective self-interference peak shaving effect on the tool working surface, a set of non-uniform gradient microgroove arrays are adopted. The microgroove spacing and depth are constructed with a variable ratio based on the eighth to thirteenth terms of the Fibonacci sequence. That is, from the starting groove to the end groove, the depth shows an obvious increasing trend, while the spacing slightly contracts. The formation logic of this arrangement is to initially disperse the high-frequency impact by forming a dense groove group at the front end of the tool, and at the same time, provide stress absorption and buffering with deep grooves in the release area at the tail end, completing the time difference adjustment between the primary stress wave and the reflected wave in the spatial dimension, thus promoting the enhanced occurrence of phase cancellation phenomenon. In specific implementation, the reference depth is selected as four hundred micrometers, and the microgroove array processing is completed by a high-precision five-axis micro-milling device. The total number of grooves on a single tool is controlled between twenty-five and thirty, and its arrangement direction maintains a constant angle with the tool rotation vector, thereby forming a circumferential spiral propagation guiding effect.

[0035] Secondly, considering that during the processing of this type of high-humic acid mixture, the tool working surface is extremely vulnerable to the infiltration of strongly polar molecules containing carboxyl and phenolic hydroxyl structures. When preparing the viscoelastic interface material used in this embodiment, based on β-glucan extracted from waste mushroom bags as the basic component, combined with nano-silica with an average particle size of ten nanometers, after alkaline treatment with triethanolamine as the buffer medium, controlling its pH value in the range of 9.5 to 10, and then adding an organosilane coupling agent containing mercapto groups, a stable cross-linked network is formed after reacting for 12 hours at 60 °C. The disulfide bond structure formed in this network has both structural flexibility and thermal responsiveness, and can undergo reversible conformational changes with the change of stress amplitude during the crushing process, effectively realizing dynamic damping adjustment. The glass transition temperature of the material is set between 58 and 62 °C after being verified by differential scanning calorimetry. During actual operation, the tool surface temperature is controlled within a range of 15 to 10 °C below this temperature zone, which can ensure that the material remains in a highly elastic state, thus continuously demonstrating high-efficiency energy dissipation ability. At the same time, to achieve the temperature control target, an infrared spectroscopic sensor is activated at the initial stage of equipment operation to continuously monitor the absorption peak position of humic acid (especially at 1580 wavenumbers) in the material feed stream. When the detected value stably exceeds the reference threshold by 20%, the cooling system adjustment logic is triggered. This logic first performs frequency domain analysis on the data collected by the piezoelectric sensor set near the tool, extracts the main impact frequency and the tool working current volatility under the current crushing state for joint analysis. When both exceed the corresponding dynamic thresholds, the tool speed is automatically adjusted and the atomized cooling module is activated to make the coolant circulate and spray at 3 °C, ensuring that the tool surface temperature does not exceed the viscoelastic material transition point, so as to maintain the material energy absorption mechanism in the best interval.

[0036] Under this typical mixing working condition, due to the mechanical response differences between different raw material components, frequency drift and energy concentration of stress waves may occur. To improve the adaptability of the tool structure to such frequency changes, in this embodiment, a topology optimization mechanism is further introduced on the original micro-groove structure. Through the real-time linkage between the integrated laser scanning device set at the tool tail and the finite element model, when the amplitude of the sub-harmonic component (such as around 800 Hz) in the vibration spectrum continuously rises and exceeds the set threshold, the system automatically executes the micro-groove parameter fine-tuning logic, that is, within the stress concentration area, the groove depth is adjusted by high-precision laser etching within 10 microns, or the groove spacing is slightly changed within 30 microns, to achieve the redistribution of the stress propagation path. The response time required for this process is controlled within 30 seconds, and due to the limited adjustment range, it basically does not affect the overall tool life or structural integrity. From the perspective of system coordination, the information transmission mechanism between control modules under the working condition is also particularly crucial. In this embodiment, the vibration data is collected 50 times per second by the piezoelectric sensor and transmitted to the central controller in a time series manner. After being synchronized with the tool current value, it is sent to the local neural network model for joint analysis. The model can predict the stress wave peak interval and energy level through learning historical data, and accordingly judge whether dynamic adjustment of the groove structure is required, whether there is a risk of approaching the material performance critical point, or whether the load operation speed should be reduced in advance, thus constituting a real-time stress regulation closed-loop mechanism integrating perception - decision - execution. This mechanism has shown strong robustness to sudden changes in raw material components and high response sensitivity after repeated tests in this scenario.

[0037] Example 2: This example combines Figures 1 to 3 to illustrate the implementation of a dynamic stress regulation method for a crusher during the production process of a biological fertilizer. As Figure 1 shown, first, an impact load is applied to the tool working surface, and then the phenomenon of transmitted stress occurs. The transmitted stress further acts to generate a primary stress wave and a reflected stress wave respectively; next, the propagation of the primary stress wave and the propagation of the reflected stress wave occur simultaneously, and then the reflected wave returns. At this time, by regulating the phase of the primary wave and the reflected wave, the waves interfere in the superposition area, and finally the regulated stress is generated and acts on the tool working surface, the microstructure, and the interface layer again.

[0038] As Figure 2 shown, the monitoring unit includes an on-line infrared spectroscopy monitoring device, a piezoelectric sensor, and a current monitoring module, which provide humic acid content information, vibration signals, and working current information to the control system respectively. After receiving this information, the control system generates a cooling control instruction and an inclination adjustment instruction, and sends these instructions to the execution unit; the execution unit includes a tool cooling system and an inclination adjustment mechanism, which respectively have a cooling effect and an angle adjustment effect on the tool system. The entire system realizes the real-time monitoring and dynamic regulation of the tool working state through a closed-loop feedback mechanism.

[0039] As Figure 3 shown, the process starts with high-fiber raw materials and enters the dynamic stress regulation system. In the system, first, stress wave conduction is carried out through the Fibonacci microgroove array, then non-linear damping is generated through the viscoelastic interface layer, and grain preferred orientation is carried out to form a low-impedance path. At the same time, the system also obtains humic acid signals through infrared spectrum monitoring and conducts dip angle gradient adjustment. The stress balance evaluation module evaluates the above processes and triggers a signal to start the cooling system according to the evaluation results. Finally, peak stress suppression is achieved.

[0040] Example 3: In this example, the depth of the th microgroove of the non-uniform gradient microgroove array is determined by the following formula: , where the depth of the nth microgroove , whose unit is usually micrometer (μm) or millimeter (mm), represents the specific depth value of the microgroove with the serial number in a series of microgrooves arranged along a specific direction (such as the radial direction or the axial direction) on the working surface of the tool. The reference depth , whose unit is the same as , is a basic parameter for calculating the depths of all microgrooves. is not selected arbitrarily, but comprehensively considers the average particle size, maximum particle size of the biological fertilizer raw materials to be crushed, the toughness and brittleness of the materials, the type of the crusher, and the size and material strength of the tool itself. For example, when processing biological organic fertilizer raw materials containing larger lumps or harder fiber bundles, a relatively large reference depth (for example, the range can be considered between 200 micrometers and 800 micrometers) may be required to provide enough space to accommodate and guide the stress wave energy generated by the impact and ensure the initial stress dispersion effect.

[0041] In this example, the calculation of the working current volatility of the crusher adopts the following formula: , where: the working current volatility , whose unit is percentage (%), is a key dynamic index for measuring the load stability of the main motor of the crusher. During the biological fertilizer crushing process, the hardness, humidity, viscosity of the materials and the uniformity of the feeding will all cause fluctuations in the motor current. An excessive volatility usually means that the crushing process is unstable and there may be a risk of material blockage or the tool is subjected to abnormal impact stress; the instantaneous current value , whose unit is ampere (A), is the current reading obtained by real-time acquisition through a current sensor installed in the motor drive circuit of the crusher, reflecting the load condition of the motor at a specific moment; the moving average current value in the previous 5 minutes , with the unit also being Ampere (A), is obtained by performing arithmetic mean or weighted mean calculation on multiple instantaneous current values collected within the past 5 minutes (or other preset statistical time windows), representing a relatively stable average load level of the recent crusher under the current working conditions. At the same time, the calculation relationship of this formula defines the working current volatility which is calculated by calculating the instantaneous current value relative to the moving average current value in the previous 5 minutes and quantifying it as the percentage of the ratio of their absolute deviation to this moving average current value . This value can sensitively capture the load mutation caused by changes in material properties or abnormal comminution states (such as increased tool wear and material accumulation in the comminution chamber). In the present invention, when this value exceeds a preset threshold (e.g., 10%), the tool cooling system will be triggered, aiming to maintain the tool working temperature within the optimal working temperature range of the preset viscoelastic composite material (i.e., below the glass transition temperature to to range), because the drastic fluctuation of the motor current is often accompanied by an increase in comminution power consumption and a rapid rise in tool temperature, resulting in the performance of the viscoelastic material filled in the microgrooves deviating from the designed state and affecting its damping energy dissipation effect. Therefore, the calculation result of the formula is the key input for realizing the active protection and optimized regulation of the performance of the viscoelastic interface layer.

[0042] When it is detected that the humic acid content of the bio-fertilizer raw material exceeds a specific threshold, the inclination angle of the microgroove array is dynamically adjusted , and its variation relationship adopts the following formula: , where: the adjusted inclination angle of the microgroove , with the unit being degree (°), represents the inclination angle of the whole or key area of the microgroove array after processing the high-humic acid bio-fertilizer with a mass of . This inclination angle is relative to a certain reference plane of the tool working surface, and its adjustment aims to change the effect of the microgroove on the highly viscous material, such as promoting the slippage of the material on the tool surface, reducing adhesion, and thus reducing the stress transmitted back due to adhesion. The initial inclination angle is set as , which is an empirical starting value applicable to bio-fertilizer raw materials with general viscosity; the inclination angle adjustment coefficient , with the unit being degree per kilogram ( ) or a similar unit representing the angle change rate caused by the treatment amount of unit mass of material. This coefficient Determination is usually based on experimental data: By crushing a series of biofertilizer samples with different and known humic acid content gradients under laboratory conditions, parameters such as the energy consumption of the crusher, the frequency of material jamming, the adhesion of the cutting tools, and the particle size distribution of the final product are recorded at different inclination angle settings. Then, through data analysis and fitting, the value that can optimally balance these performance indicators is found, and a suitable value (for example, selected within the range of to ) is chosen such that the incremental increase in the inclination angle can effectively cope with the enhanced adhesion effect caused by the increase in humic acid content, but not so much as to overly increase the inclination angle and lead to a decrease in the crushing efficiency of certain material components. The mass of the processed material , with the unit of kilograms (kg) or other mass units, represents the cumulative mass of the biofertilizer raw materials that have passed through the crusher since the start of processing high-humic acid materials (i.e., the moment when the humic acid content exceeds 20%).

[0043] In the present invention, the stress balance degree index is used to quantitatively evaluate the cancellation interference effect of stress waves, and its calculation uses the following formula: , where: The stress balance degree index , with the unit of percentage (%), is used to evaluate the uniformity of the dynamic stress distribution on the cutting tool working surface. A higher value (ideally close to 100%) indicates that the stress difference at each part of the cutting tool working surface is smaller and the stress distribution is more balanced, which means that the stress concentration phenomenon is effectively suppressed, conducive to extending the fatigue life of the cutting tool and improving the crushing efficiency; the minimum stress value on the cutting tool working surface, with the unit usually being Pascal (Pa) or Megapascal (MPa), represents the lowest stress value in the dynamic stress distribution that is real-time monitored through a sensor array (such as a micro strain gauge array) or calculated through a finite element analysis (FEA) model within a certain investigation time period or in a specific area of the cutting tool working surface; the maximum stress value on the cutting tool working surface, with the unit being the same as , represents the highest stress value corresponding to the same investigation conditions. The ways to obtain and In practical applications, high-frequency response micro strain sensors can be arranged in key cutting tool working areas (for example, the parts most prone to wear or stress concentration), real-time collect dynamic strain data, and convert them into dynamic stress values in combination with the elastic modulus of the cutting tool material. The index in the formula is a direct quantitative indicator for evaluating the effect of the dynamic stress wave self-interference regulation system of the present invention. When When it is lower than a preset threshold (e.g., 85%), it indicates that the stress distribution on the tool working surface becomes uneven and new stress concentration points may appear. At this time, the topological optimization program of the micro-groove array will be triggered. By iteratively adjusting parameters such as the depth and spacing of the micro-grooves, the stress distribution is re-optimized to make it rise back to the ideal level. This mechanism constitutes an important closed-loop feedback control link in the dynamic stress regulation method of the present invention, ensuring that the tool can always maintain a good stress balance state during long-term operation.

[0044] In the present invention, the loss modulus of the viscoelastic interface layer varies with the stress amplitude and satisfies a non-linear relationship, which is characterized by the following formula: , where: the loss modulus (of the viscoelastic interface layer) , whose unit is usually Pascal (Pa) or Megapascal (MPa), is a key dynamic mechanical parameter characterizing the energy dissipation ability of the material under alternating stress. The larger the loss modulus, the better the damping performance of the material, that is, more mechanical energy can be converted into heat energy and dissipated; the loss modulus at low stress , whose unit is the same as , represents the initial loss modulus value of the viscoelastic composite material when the stress amplitude tends to zero or is very small. This is a parameter reflecting the inherent damping characteristics of the material under quasi-static or micro-vibration conditions, and its value is mainly determined by the molecular structure of the material, the cross-linking network density, and the environmental temperature (relative to its glass transition temperature ); the non-linear coefficient , whose unit is the reciprocal of the square of the stress unit (e.g., or ), is a parameter characterizing the sensitivity of the loss modulus to the stress amplitude. The larger the value, the faster the loss modulus decreases with the increase of the stress amplitude; the stress amplitude , whose unit is Pascal (Pa) or Megapascal (MPa), refers to the amplitude of the alternating stress acting on the viscoelastic interface layer. During the crushing process of the biological fertilizer, each impact between the tool and the material will generate stresses with different amplitudes on the interface layer. The mathematical relationship expressed by the formula is an exponential decay form, which reveals a very important characteristic of the β-glucan-based viscoelastic composite material used in the present invention: its energy dissipation ability (i.e., the loss modulus ) is not constant, but decreases non-linearly with the increase of the stress amplitude , the material exhibits strong damping; while when the impact stress amplitude is very large, due to term rapidly decreases, and the loss modulus also decreases significantly. This non-linear behavior is of special significance for the regulation of stress waves: it enables the interface layer to efficiently absorb and dissipate medium- and low-intensity stress waves (which are often the main factors causing fatigue cumulative damage of materials), while for extremely high-intensity stress peaks that may cause catastrophic damage, although the direct dissipation ability decreases, combined with the geometric dispersion effect of the microgroove array, effective peak suppression can still be achieved; this intelligent damping characteristic enables the tool system to achieve more optimized energy management and stress regulation under complex and broad impact load spectra.

[0045] Example 4: In a new crushing line upgrade test for highly viscous bio-fertilizer raw materials, a large amount of fermented straw and mycelium waste rich in humic acid was mixed in the raw materials. Due to the strong adhesion and certain crystalline hardening structure formed during the primary fermentation process, typical problems such as abnormal tool temperature rise, increased current fluctuation, and serious stress concentration at the tool tip occurred after the traditional crusher operated continuously for two hours. In order to verify the actual adaptability of the stress regulation mechanism of the present invention in such highly complex raw materials, this example takes this production scenario as the background, combines the linkage mechanism of system perception, structural design, material response, and feedback regulation, and further refines and improves the specific implementation method.

[0046] First, at the initial stage of the equipment entering the crushing operation, the control system receives the data packet uploaded by the upstream material sensor. The data shows that the humic acid absorption peak of the current incoming raw material has stably exceeded the wavenumber range of one thousand five hundred and eighty reciprocal centimeters, and the average value is higher than the reference threshold by 23% in continuous sampling. It is initially determined that the overall viscosity of the material is relatively high. Based on this, the system triggers the inclination dynamic adjustment module. This module gradually applies torque in the inclination adjustment structure in the front area of the tool processing, slowly increasing the trough inclination at a rate of 0.03 degrees for every ten kilograms of material processed, so that it forms an approximately radially diffused arrangement on the tool working surface, thereby inducing the high-adhesion components to dissipate along the set direction at the initial stage of cutting, avoiding their adhesion and accumulation at the tool tail, and thus alleviating the risk of stress backpropagation. At this stage, due to the significant increase in humic acid content, the viscoelastic composite material in the original microgrooves on the tool surface faces stronger shear and rebound loads. To ensure that its dynamic damping ability remains in the efficient range, the tool temperature control system automatically enables the cooling mode through a dual-channel feedback mechanism. Its specific logic is as follows: The piezoelectric sensor on the tool mounting base outputs the frequency-domain signal data in real time. When a continuous increase in amplitude is observed in the middle frequency band (about 900 to 1100 Hz), it is determined that there is a trend of stress wave energy aggregation. If at the same time the motor current volatility is greater than 10%, the system enters the active intervention process. At this time, the cooling module preferentially switches to the low-temperature atomized spraying state, maintaining the tool surface at a constant temperature within 40 degrees Celsius, ensuring that the material filled in the microgrooves always remains in the high elastic state, thereby maintaining its high energy absorption ability in the non-linear damping mechanism, that is, when the stress amplitude is in the medium-high range of 30 MPa to 50 MPa, the loss modulus will not rapidly decrease due to temperature rise, thus maintaining the effective attenuation ability of the material body to dynamic stress.

[0047] At the same time, the system entered the steady-state crushing period. Due to the presence of a certain proportion of incompletely fermented crude fiber clumps in the raw materials, the stress wave showed signs of reflection accumulation in the middle section of the tool. During this process, the monitoring system detected that the stress balance index dropped to 83%, close to the set intervention threshold. After automatic judgment, the topology optimization module optimized the groove depth of the three microgrooves in the trailing edge area of ​​the tool through laser reconstruction technology within a response time of 30 seconds, and adjusted the depth control to within the range of plus or minus ten microns of the original design value. After the change, the groove distribution frequency was fine-tuned by about three percent to form a new local rhythm interval. Its geometric period produced phase cancellation coupling with the current main stress wave propagation wavelength, which reduced the reflected wave intensity by more than ten percent, thereby restoring the overall stress equilibrium state. It is worth mentioning that in order to further enhance the stability of the tool system in long-term operation, this embodiment introduces a predictive judgment mechanism in the system logic, that is, through the collaborative analysis of the vibration spectrum and current fluctuation rate in the past ten minutes, a fluctuation trend model is established, and the stress peak range in the next five minutes is predicted in combination with the current tool surface temperature and processing load conditions. When the system predicts that there is a risk of sudden change in material composition in the next cycle, the cooling intensity and tool speed will be adjusted in advance, and the laser fine-tuning path parameters will be preloaded, so that the system can complete the pre-adjustment preparation before the extreme stress peak actually occurs, thereby effectively shortening the system response time and improving the overall robustness. These are all extended implementation methods that can be known to ordinary technicians in this field.

[0048] Example 5: In a typical bio-fertilizer pretreatment production line upgrade scenario, the processed material is a mixed matrix of corn straw after semi-fermentation treatment, which is mixed with fiber clusters that have not been completely depolymerized and some protein-humic acid complexes, showing physical properties of high viscoelasticity and weak crystallization hardening. In the trial operation of the original system, microscopic stress concentration points appeared on the surface of the crushing tool at the beginning of operation and heated up significantly within twenty minutes, causing the vibration frequency of the equipment to shift upward, the current fluctuation rate to increase and trigger multiple frequency reduction protections, indicating that the traditional scheme cannot effectively construct a dynamic stress regulation closed loop under such complex materials. For this reason, this embodiment introduces the stress regulation mechanism based on microstructure-material-information feedback synergy of the present invention, focusing on the typical pressure input response path under this working condition, and showing its three-level response mechanism of structural dispersion + material absorption + feedback intervention.

[0049] First, before entering this mixture processing section, the infrared monitoring module identifies the absorption peak position of the material. After the system determines that its humic acid content has been higher than 25% for a long time, it is initially preset as a high-risk stress feedback working condition. On this basis, for the non-uniform gradient microgroove array machined at the front end of the tool, a parameter structure is constructed using the depth-to-spacing ratio derived from the 9th to 15th Fibonacci sequences. The initial reference value of the depth is set at 450 micrometers, the total number of microgrooves is 33, and the grooves are continuously arranged from the tip of the tool to the trailing edge. The arrangement direction maintains a 20-degree angle with the tangential direction of the tool rotation to construct a main stress guiding channel in a rotating and twisted shape along the cutting vector direction. This design is based on the analysis results of the impact load spectrum of this type of material in the previous simulation, and it is confirmed that the main peak energy frequency is between 900 and 1000 Hz. Therefore, the equivalent geometric period of the microgrooves forms a certain structural resonance relationship with this wavelength range, which is conducive to inducing the reflection and interference of stress waves and promoting phase cancellation. The viscoelastic material filled in the microgrooves uses β-glucan extracted from discarded Pleurotus eryngii mushroom bags as the main chain material, supplemented with nano-silica with a particle size range of 13 nanometers, and the mass ratio is controlled at 1:1.1. A mercapto-functionalized organosilane modifier is used to increase its cross-linking density with cysteine groups. During the preparation process of the composite material, a stable reaction is carried out at a temperature of 62 °C for 12 hours. The glass transition temperature of the obtained material is distributed between 58 and 63 °C. The dynamic mechanical analysis results show that it exhibits typical stress-dependent nonlinear damping characteristics in the stress range of 30 MPa to 50 MPa. Specifically, the loss modulus first increases and then decreases as the impact amplitude increases. This response mechanism is used to achieve the efficient dissipation of medium-amplitude stress waves, while the response to high-amplitude stress mainly relies on the geometric structure to provide a primary dispersion path, thus forming a hierarchical distribution strategy of stress energy.

[0050] After the material officially enters the crushing area, the system starts the real-time monitoring module. The piezoelectric sensor set on the tool base collects 50 groups of vibration spectrum data per second, and at the same time, synchronously cross-analyzes the instantaneous power data collected by the current sensor. The system couples the working current volatility calculated from the difference between the current five-minute moving average current value and the instantaneous current and the vibration characteristic frequency and inputs them into the local model. If it is determined If it exceeds 11% and the frequency peak shifts to above 1 kHz, the atomization cooling system is activated. Meanwhile, the temperature of the spray liquid is controlled within 2 °C, and the average temperature of the tool surface is maintained below the glass transition temperature of the composite material by 15 °C to ensure that the material is in the high elastic state and maintains a high damping state without being damaged by heat. When the tool temperature exceeds 10 °C above the transition point of the material, the decrease in the dynamic modulus exceeds 40%, which will seriously weaken the energy dissipation efficiency. Therefore, cooling needs to be triggered in advance to avoid the performance degradation of this key material. When the system monitors that the stress balance index is lower than 85, that is, the stress distribution on the tool surface tends to be uneven, the laser fine-tuning system is immediately called to adjust the depth of three micro-grooves with stress concentration in the trailing edge area of the tool respectively. The adjustment range is controlled within plus or minus 7 μm, and the spacing adjustment does not exceed 20 μm. The goal is to re-induce the stress wave reflection path in the local wavelength range through micro-reconstruction means to restore the interference balance state. This process takes no more than 25 seconds, does not affect normal crushing operations, and has the ability to dynamically complete the stress control closed-loop under the condition of uninterrupted operation.

[0051] Starting from identifying the material properties at the upstream of the entire system, through multiple mechanisms such as presetting the inclination gradient, structural guiding arrangement, material property matching, information closed-loop response, and geometric local reconstruction, a stress regulation grid is jointly formed. The typical operation result in this scenario is that the tool usage cycle is extended by 32% and the unit energy consumption is reduced by 17%. Moreover, there is no system response lag at multiple raw material composition mutation nodes. This result can stably construct an effective stress path regulation system through an adaptive mechanism in the working condition of high-viscosity and high-fiber complex mixed materials, achieving dynamic protection of the tool and optimized control of system energy consumption.

[0052] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to include all changes falling within the meaning and scope of the equivalent elements of the claims in the present invention.

Claims

1. A method for dynamically regulating the stress of a crusher during the production process of a biological fertilizer, characterized in that, The method includes the following steps: Step a, set a non-uniform gradient micro-groove array on the tool working surface. The micro-grooves have an inclination gradient ranging from 5° to 25°, and the depth of the micro-grooves and the spacing are arranged non-uniformly along the tool working surface according to the variable ratio of the Fibonacci sequence. Among them, the depth of the nth micro-groove is determined by the formula , is the reference depth, is the th term of the Fibonacci sequence; Step b, fill the inside of the microgroove with a viscoelastic composite material formed by β-glucan extracted from waste edible mushroom mycelium and treated with alkali and nano-silica to construct an interfacial layer with non-linear damping characteristics. The particle size range of the nano-silica is 10-15 nm, and the surface is grafted with a mercapto-modified group to form a disulfide bond cross-linking network with cysteine residues in β-glucan. The glass transition temperature of the viscoelastic composite material is set in the range of 55°C to 65°C; Step c: regulating the grain orientation of the tool substrate material through an electromagnetic field-assisted directional solidification process, such that the included angle between the long axis of the grains and the cutting force direction is less than 10°, thereby forming a stress wave guiding path with low impedance inside the tool; Step d, monitor the working current volatility of the crusher in real time , when exceeds the preset threshold by 10%, is the instantaneous current value, is the moving average current value in the previous 5 minutes, start the tool cooling system, and maintain the tool working temperature within to range; Step e: the geometric parameters of the non-uniform gradient microgroove array, the dynamic mechanical response characteristics of the viscoelastic interface layer, and the grain preferred orientation of the tool substrate material together constitute a dynamic stress wave self-interference regulation system. During the bio-fertilizer pulverization process, by inducing and regulating the propagation path and phase of the stress wave at the microscale, promoting the destructive interference between the primary stress wave and the reflected stress wave to achieve spatial equalization and peak suppression of the dynamic stress on the tool working surface.

2. A method for dynamically regulating the stress of a crusher in the production process of a biological fertilizer according to claim 1, characterized in that In the non-uniform arrangement of the Fibonacci sequence ratio in step a, the depth ratio of adjacent micro-grooves With the increase of the groove sequence gradually approaches the golden ratio .

3. A method for dynamically regulating the stress of a crusher during the production process of a biological fertilizer according to claim 1, characterized in that, In step b, the mass ratio of nano-silica to β-glucan is controlled within the range of 0.8:1 to 1.2:1 to adjust the damping coefficient and phase transition temperature of the viscoelastic composite material.

4. A method for dynamically regulating the stress of a crusher during the production process of a biological fertilizer according to claim 1, characterized in that, The electromagnetic field-assisted directional solidification process in step c includes the following stages: In the first stage, an axial static magnetic field is applied, with a magnetic field strength of 1.0 T to 1.2 T and a duration of 20 to 40 minutes; In the second stage, it is switched to a radial rotating magnetic field, with a magnetic field strength of 0.4 T to 0.6 T, a rotation frequency of 1 to 3 Hz, and a duration of 10 to 20 minutes; In the third stage, an axial pulsed magnetic field is applied, with a magnetic field strength of 0.6 T to 1.0 T, a pulse frequency of 3 to 7 Hz, and a duration of 15 to 30 minutes.

5. A method for dynamically regulating the stress of a crusher during the production process of a biological fertilizer according to claim 1, characterized in that, It also includes an infrared spectroscopy on-line monitoring device arranged at the feed inlet of the crusher to detect the humic acid content of the biological fertilizer raw materials in real time. When the detected humic acid content exceeds 20%, the inclination gradient of the microchannel array in step a is dynamically adjusted so that the inclination increases with the quality of the processed materials , and its variation relationship is , where is the inclination adjustment coefficient, and its value range is 0.01° / kg to 0.05° / kg.

6. A method for dynamically regulating the stress of a crusher during the production process of a biological fertilizer according to claim 1, characterized in that, The cancellation interference effect of the stress wave in step e is quantitatively evaluated by the stress balance degree index and , where and are the minimum and maximum stress values on the tool working surface respectively. When is lower than 85%, the topology optimization program of the micro-groove array is triggered.

7. A method for dynamically regulating the stress of a crusher during the production process of a biological fertilizer according to claim 6, characterized in that, The topology optimization program is based on a finite element analysis model, iteratively adjusting the depth and spacing of the micro-grooves to maximize the stress balance index and driving a laser etching device to perform in-situ repair on the tool surface after optimization, with the repair accuracy controlled within the range of ±3μm.

8. A method for dynamically regulating the stress of a crusher during the production process of a biological fertilizer according to claim 1, characterized in that, Dynamic storage modulus of the viscoelastic interface layer and loss modulus vary with the stress amplitude and satisfy a nonlinear relationship: , where is the loss modulus at low stress, is the nonlinear coefficient, which is adjusted by controlling the crosslinking density of β-glucan and nano-silica.

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