Concrete mortar mixing and stirring system

Abstract

A concrete mortar mixing and stirring system belongs to the technical field of concrete production equipment. Aiming at the problems that an existing stirring system is difficult to accurately judge the mixing uniformity of concrete mortar and the quality is easily influenced due to excessive stirring or insufficient stirring, the system comprises a stirring tank, a vibration signal acquisition unit, a torque monitoring unit and a control unit, stirring blades in a stirring tank are driven by a motor, a vibration signal acquisition unit captures a tank body vibration signal, a torque monitoring unit detects the torque change of the motor, and a control unit decomposes the tank body vibration signal into a frequency domain signal and extracts a preset aggregate collision vibration frequency band energy value to generate a vibration energy sequence; and analyzing the torque change fluctuation intensity to generate a torque variation coefficient sequence, calculating a correlation coefficient sequence of the two, generating an adaptive shutdown threshold by a sliding time window, and cutting off a motor power supply when the correlation coefficient sequence is continuously lower than the threshold for a preset number of times. The device is mainly used for automatic stirring control of concrete mortar, and precise starting and stopping of the stirring process are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building material production equipment. More particularly, the present application relates to a concrete mortar mixing and stirring system. BACKGROUND

[0002] In the field of building construction, the stirring quality of concrete mortar directly affects the structural strength and stability of subsequent projects, and the precise control of the stirring process is the key link to guarantee the stirring quality. The traditional concrete mortar stirring system usually relies on a preset fixed stirring time to control the stirring process, that is, a fixed time length is set according to experience or formula, and the stirring is automatically stopped when the stirring reaches the time length. The core basis of this method is to assume that materials of the same formula and dosage can reach a uniform mixing state within a fixed time. In actual stirring process, factors such as the initial state of the materials, particle distribution, humidity, and real-time running state of the stirring equipment fluctuate significantly, making it difficult for the fixed stirring time control method to adapt to complex and variable working conditions. To improve this problem, some stirring systems attempt to determine the stirring end point through manual observation or simple parameter monitoring, but manual observation is highly subjective and its accuracy is greatly influenced by the experience of the operator. Therefore, how to realize self-adaptive stop control of the stirring process is a technical problem that has long been urgent to solve in the industry. SUMMARY

[0003] An object of the present application is to provide a concrete mortar mixing and stirring system that realizes precise determination of the stirring end point through correlation analysis of vibration and torque, thereby avoiding insufficient or excessive stirring caused by fixed time control and effectively guaranteeing the stirring quality of concrete mortar.

[0004] To achieve these objects and other advantages and in accordance with the purpose of the application, as embodied and broadly described herein, there is provided a concrete mortar mixing and stirring system, comprising: a stirring tank for containing concrete mortar raw materials, wherein the stirring tank is provided with stirring blades driven by a motor for stirring; a vibration signal acquisition unit installed on the outer wall of the stirring tank or the stirring blades for capturing the tank vibration signal in real time during the stirring process; a torque monitoring unit connected with the output shaft of the motor for detecting the torque change of the motor during operation; a control unit connected with the vibration signal acquisition unit and the torque monitoring unit, wherein the control unit is configured to: decompose the tank vibration signal into a frequency domain signal, extract the energy value of a preset aggregate collision vibration frequency band and generate a vibration energy sequence, analyze the fluctuation intensity of the torque change, generate a torque variation coefficient sequence, and calculate the correlation coefficient sequence between the vibration energy sequence and the torque variation coefficient sequence; In the initial stirring stage, the adaptive shutdown threshold is continuously generated in a sliding time window manner: a continuous dynamic data window is divided according to a time length of 30-120 seconds; the average value of the correlation coefficient in each data window is calculated; the standard deviation of the correlation coefficient in each data window is calculated as the fluctuation amplitude; the adaptive shutdown threshold is set as: the average value of the current window minus the product of the preset sensitivity multiple and the fluctuation amplitude; when the window data is updated, the threshold is updated synchronously, wherein, when the data points are less than 50% of the window capacity, a preset fixed threshold based on the current material formula is used, and the preset sensitivity multiple is 1.5-3; When the correlation coefficient sequence continuously falls below the adaptive shutdown threshold for a preset number of times, the motor power is cut off.

[0005] Preferably, the control unit is further configured to: monitor the rotation speed of the motor; identify a raw material feeding completion signal, and take the raw material feeding completion signal as the starting point of the initial stirring stage; after the starting point, continuously monitor whether the rotation speed of the motor reaches a preset stable running rotation speed; after the rotation speed of the motor reaches the stable running rotation speed and maintains for a preset time length, start acquiring and recording the energy sequence and the torque variation coefficient sequence; based on the energy sequence and the torque variation coefficient sequence recorded in the preset time length, calculate the statistical characteristics of the correlation coefficient sequence, and generate the adaptive shutdown threshold accordingly.

[0006] Preferably, the vibration signal acquisition unit comprises a plurality of vibration sensors installed at different positions of the stirring tank; the control unit is further configured to: based on the signal consistency analysis of the plurality of vibration sensors, identify non-material impact interference from the external environment; when significant external interference is detected, start a vibration signal filtering mechanism: use an adaptive filter to suppress the vibration component related to the external interference; based on the filtered vibration signal, regenerate the vibration energy sequence.

[0007] Preferably, the control unit is further configured to: establish an aggregate collision vibration feature library, which stores the vibration spectrum features of typical aggregate collisions under different working conditions; before generating the vibration energy sequence, analyze the transient characteristics of the vibration signal in real time; when a transient event significantly deviating from the current aggregate collision feature library mode is detected in the vibration signal, it is determined to be non-aggregate collision interference; Start the interference event filtering mechanism: when calculating the vibration energy sequence, remove or significantly attenuate the vibration data in the time period determined as the interference event.

[0008] Preferably, it further comprises a vibration signal preprocessing unit connected with the vibration signal acquisition unit, and the vibration signal preprocessing unit: Before the motor starts, collect the environmental vibration spectrum, identify and record the high-frequency narrow-band noise components greater than 500 Hz in the environmental vibration, and establish a high-frequency noise baseline model; Apply an adaptive notch filter to dynamically remove coherent components; When the control unit extracts the aggregate collision vibration frequency band energy, it is calculated based on the filtered vibration signal; The high-frequency noise baseline model is automatically updated after each material emptying.

[0009] Preferably, the control unit further comprises a restart transient analysis module configured to perform the following operations: During each start of the motor, the vibration energy sequence and the torque coefficient of variation sequence during the period from zero speed to stable speed are recorded in real time; Divide the above two sequences into consecutive time segments, and calculate the correlation coefficient of the two sequences in each time segment; Determine the time required for the correlation coefficient to grow from the initial value to 90% of the stable value as the material stick response time; According to the length of the stick response time, the torque coefficient of variation data in the corresponding time period after the motor starts is marked as transition section data; When calculating the correlation coefficient sequence of the vibration energy sequence and the torque coefficient of variation sequence, the values of the transition section data are weighted according to a predetermined rule: the longer the stick response time, the lower the weighting ratio; the shorter the stick response time, the higher the weighting ratio.

[0010] Preferably, the control unit is configured with a segregation warning module to perform the following operations: During the stable mixing stage, the vibration sensor signals installed at three heights on the mixing tank are synchronously collected; Calculate the average energy of the vibration signals at each height in the aggregate collision frequency band of 50-1500 Hz; Take the middle energy value as the reference, calculate the relative deviation of the upper and lower energy values from the middle value: If the upper deviation is > +15% and the lower deviation is < -10%, it is determined to be aggregate floating type segregation; If the lower deviation is > +15% and the upper deviation is < -10%, it is determined to be paste sinking type segregation; When segregation is detected, the mixing time is automatically extended based on the type of segregation, and a stepwise lifting program of the mixing shaft speed is triggered.

[0011] Preferably, the stirring tank outer wall is integrated with an ambient temperature sensor, and a material moisture content sensor is arranged at the top feeding port of the tank body; the control unit is configured to execute a dynamic reference calibration process: The preset standard working condition parameter reference value is that the temperature reference value is 25 DEG C, and the moisture content reference value is 10 %. The ambient temperature sensor data and the material moisture content sensor data are monitored in real time, and when it is detected that the real-time data deviates from the reference value, compensation is made according to the following rules: The temperature compensation mechanism is that when the ambient temperature is higher than the reference value by 5 DEG C, the determination threshold of the vibration energy sequence is reduced by 5 %, and when the ambient temperature is lower than the reference value by 5 DEG C, the determination threshold is increased by 5 %. The humidity compensation mechanism is that when the material moisture content is higher than the reference value by 1 %, the adaptive shutdown threshold of the correlation coefficient sequence is lowered by 3 %, and when the material moisture content is lower than the reference value by 1 %, the adaptive shutdown threshold is increased by 3 %. The compensation execution constraint is that the single compensation adjustment amplitude does not exceed ± 15 % of the original threshold, and when the ambient temperature or the material moisture content returns to the reference value, the corresponding compensation mechanism is automatically released.

[0012] The present application at least includes the following beneficial effects: First, the present application realizes accurate judgment of the stirring end point through correlation analysis of vibration and torque, avoids insufficient or excessive stirring caused by fixed time control, adapts to changes in different material states, effectively guarantees the stirring quality of concrete mortar, and reduces energy consumption; the present application takes the completion of feeding as the starting point and waits for the speed to be stable before collecting data, effectively eliminates the unstable interference in the feeding process and the initial starting period, makes the calculation of the correlation coefficient sequence more in line with the actual stirring state, further improves the accuracy of the adaptive shutdown threshold, and ensures that the stirring end point judgment is not affected by the transition stage data.

[0013] Secondly, the embodiment effectively distinguishes the effective vibration caused by material collision and external environmental interference through the combination scheme of multi-sensor comparison and adaptive filtering, avoids the problem that a single sensor is easily affected by local interference. Even in a complex environment with equipment vibration, personnel collision and the like on the construction site, pure aggregate collision vibration signals can still be extracted, making the subsequent correlation coefficient calculation more reliable, thereby improving the anti-interference ability and stability of the adaptive shutdown control; through the establishment of a feature library and transient analysis, the vibration interference caused by non-aggregate collision can be accurately identified, compared with simple filtering processing, the abnormal signals irrelevant to the material are more targetedly excluded. This makes the vibration energy sequence only reflect the true state of aggregate collision, ensures that the correlation analysis of the vibration energy sequence and the torque variation coefficient sequence is not disturbed, and further improves the accuracy of the mixing endpoint judgment, and is especially suitable for the working conditions where impurities may be mixed in the raw materials or the equipment has a slight fault.

[0014] Thirdly, the embodiment avoids the mixing of noise energy into the aggregate collision frequency band by targeted elimination of high-frequency noise, makes the calculation of the vibration energy sequence more accurate, provides a reliable data basis for the subsequent correlation coefficient analysis, and is especially suitable for scenarios where the noise characteristics of the equipment change after long-term use; when calculating the correlation coefficient sequence of the vibration energy sequence and the torque variation coefficient sequence, the control unit adjusts the data in the transition section according to the above weighting proportion, that is, the torque variation coefficient value actually participating in the calculation is the original value multiplied by the weighting proportion. This processing method effectively reduces the influence of material stickiness characteristics on the correlation analysis in the starting stage, avoids the low correlation coefficient caused by the distortion of the initial stage data, makes the generation of the adaptive shutdown threshold more consistent with the actual mixing process of the material, and is especially suitable for the mixing control of high-viscosity mortar.

[0015] Fourthly, the embodiment promotes the up-and-down convection of the material and improves the uneven distribution of the aggregate by targeted adjustment of the mixing time and the rotating speed. The embodiment can monitor the segregation state of the material in the tank in real time and automatically take corrective measures, avoids the engineering quality problems caused by the direct use of segregated material, and improves the intelligent level of the mixing system; through dynamic compensation of the environmental parameters, the system can adapt to the mixing requirements under different temperature and humidity conditions, avoids the threshold setting deviation caused by environmental changes, and ensures that the mixing endpoint can be accurately judged under various working conditions.

[0016] Other advantages, objects and features of the present application will be apparent from the following description, and will be appreciated by those skilled in the art. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The working flowchart of the concrete mortar mixing and mixing system according to one of the technical solutions of the present application; Figure 2The flow chart of the shutdown threshold generating according to one of the technical solutions of the present application. DETAILED DESCRIPTION

[0018] The present application will be further described in conjunction with the accompanying drawings so that those skilled in the art can implement the present application according to the description and drawings.

[0019] According to one embodiment of the present application, as shown in Figure 1 , Figure 2 The concrete mortar mixing and stirring system comprises: A stirring tank for containing concrete mortar raw materials, wherein the stirring tank is provided with stirring blades driven to stir by a motor; A vibration signal acquisition unit installed on the outer wall of the stirring tank or the stirring blades for capturing the tank vibration signal in real time during stirring; A torque monitoring unit connected with the motor output shaft for detecting the torque change when the motor is running; A control unit connected with the vibration signal acquisition unit and the torque monitoring unit, wherein the control unit is configured to: decompose the tank vibration signal into a frequency domain signal, extract the energy value of a preset aggregate collision vibration frequency band and generate a vibration energy sequence, analyze the fluctuation intensity of the torque change, generate a torque variation coefficient sequence, and calculate the correlation coefficient sequence between the vibration energy sequence and the torque variation coefficient sequence; In the initial stirring stage, the adaptive shutdown threshold is continuously generated in a sliding time window manner: the continuous dynamic data window is divided according to the time length of 30-120 seconds; the average value of the correlation coefficient in each data window is calculated; the standard deviation of the correlation coefficient in each data window is calculated as the fluctuation amplitude; the adaptive shutdown threshold is set as: the average value of the current window minus the product of the preset sensitivity multiple and the fluctuation amplitude; when the window data is updated, the threshold is updated synchronously, wherein when the data points are less than 50% of the window capacity, a preset fixed threshold based on the current material formula is used, and the preset sensitivity multiple is 1.5-3; When the correlation coefficient sequence is continuously lower than the adaptive shutdown threshold for a preset number of times, the motor power is cut off, and when the correlation coefficient sequence is continuously lower than the adaptive shutdown threshold for N times (N≥5) in the stable stirring stage, and at the same time the following conditions are met, the motor power is cut off: the fluctuation rate of the vibration energy sequence in the period is less than or equal to 15% of the preset reference value; the standard deviation of the torque variation coefficient sequence is in a convergent state (≤30% of the initial fluctuation value) for 3 sampling periods, no significant external interference signal is detected (according to the consistency determination of multiple sensors), and the single sampling interval is not less than 2 seconds (to avoid high-frequency noise interference). The stirring tank is in a cylindrical structure, a feeding port is arranged at the top, a discharge valve is arranged at the bottom, and multiple mounting seats are uniformly distributed on the stirring tank wall for fixing sensors. The stirring blade is in a spiral shape and is welded on the stirring shaft, the stirring shaft is connected with the motor output shaft through a coupling, a three-phase asynchronous motor is selected for the motor and a speed reducer is configured to adjust the stirring speed; the vibration signal acquisition unit adopts a piezoelectric acceleration sensor and is fixed on the mounting seat on the outer wall of the stirring tank through bolts; the torque monitoring unit is a strain gauge torque sensor and is connected in series between the motor output shaft and the speed reducer to output a torque electric signal in real time; the control unit adopts an industrial PLC controller, an A / D conversion module is built-in to receive the vibration and torque signals, and a touch screen is provided for parameter setting and state display; In operation, the operator adds concrete mortar raw materials through the feeding port, starts the motor to drive the stirring blade to rotate, and the raw materials are subjected to shearing, overturning and mixing in the stirring tank. The vibration signal acquisition unit continuously captures the tank vibration signal and transmits it to the control unit. The control unit first performs Fourier transform on the signal to obtain a frequency domain signal, extracts the energy value of the 100-1000Hz frequency band (preset as the aggregate collision vibration frequency band), and generates a vibration energy sequence in time sequence. At the same time, the torque monitoring unit detects the torque change of the motor output shaft in real time, and the control unit calculates the ratio of the standard deviation to the average value of the torque in a unit time as the torque variation coefficient, and generates a torque variation coefficient sequence in time sequence. Subsequently, the control unit calculates the correlation coefficient of the two sequences at the same time point to form a correlation coefficient sequence; in the initial stirring stage, the control unit divides the data with a sliding time window of 60 seconds. For each window, first calculate the average of the correlation coefficient, then calculate the standard deviation as the fluctuation amplitude, and set the adaptive shutdown threshold to the current window average minus 2 times the fluctuation amplitude (preset sensitivity multiple is 2). When the window data is less than 30 seconds (i.e. 50% of the window capacity), a preset fixed threshold (based on the current material formula pre-stored in the system) is called. When the correlation coefficient sequence is less than the adaptive shutdown threshold for 5 times (preset number), the control unit outputs a power-off signal to the contactor of the motor to cut off the power supply and stop stirring. By using the technical scheme, the present application realizes accurate judgment of the stirring end point through the correlation analysis of vibration and torque, avoids insufficient or excessive stirring caused by fixed time control, adapts to the changes of different material states, effectively guarantees the stirring quality of concrete mortar, and reduces energy consumption.

[0020] According to another embodiment of the present application, the control unit is further configured to: monitor the speed of the motor (a Hall speed sensor is installed on the motor to monitor the speed in real time by detecting the speed pulse signal of the motor output shaft); identify the raw material feeding completion signal (the raw material feeding completion signal is triggered by an infrared opposite sensor installed on the edge of the feeding port, and when the sensor detects no material passing for a certain time, it is determined that the feeding is complete, and the time without material passing can be set according to different raw materials), and the raw material feeding completion signal is used as the starting point of the initial stirring stage; After the starting point, continuously monitor whether the speed of the motor reaches the preset stable running speed (the preset stable running speed is set in the touch screen according to the material formula, generally 15-30r / min); After the speed of the motor reaches the stable running speed and maintains for a preset time, start acquiring and recording the energy sequence and the torque variation coefficient sequence; Based on the energy sequence and the torque coefficient of variation sequence recorded in the preset time length, the statistical features of the correlation coefficient sequence are calculated, and the adaptive shutdown threshold is generated accordingly. After starting, the control unit starts timing after receiving the feeding completion signal, and continuously monitors the motor speed through the speed sensor. When the speed reaches the preset stable running speed and there is no fluctuation of more than ±5% for 30 seconds, the control unit determines that the motor enters a stable running state, and at this time the vibration energy sequence and the torque coefficient of variation sequence recording program is started. Within the 30 seconds of stable time length, the control unit collects data at an interval of 1 second to generate corresponding vibration energy and torque coefficient of variation data sets; based on these data, the control unit first calculates the correlation coefficient sequence, and then calculates the average, maximum and minimum of the sequence and other feature parameters, and adjusts the calculation parameters of the initial adaptive shutdown threshold based on this. For example, if the average value of the correlation coefficient in the stable stage is high, it means that the material mixing state is good, and the sensitivity multiple can be appropriately reduced; if the fluctuation is large, the weight of the fluctuation amplitude in the threshold calculation is increased. By using the technical scheme, the present application collects data after waiting for the speed to stabilize after taking the feeding completion as the starting point, effectively eliminates the unstable interference in the feeding process and the initial stage of starting, makes the calculation of the correlation coefficient sequence more in line with the actual mixing state, further improves the accuracy of the adaptive shutdown threshold, and ensures that the mixing endpoint judgment is not affected by the transition stage data.

[0021] According to another embodiment of the present application, the vibration signal acquisition unit comprises a plurality of vibration sensors installed at different positions of the mixing tank; the control unit is further configured to: Based on the signal consistency analysis of the plurality of vibration sensors, non-material impact interference from the external environment is identified; When significant external interference is detected, a vibration signal filtering mechanism is started: an adaptive filter is used to suppress the vibration components related to external interference; The vibration energy sequence is regenerated based on the filtered vibration signal. The vibration signal acquisition unit includes four vibration sensors, which are respectively installed on the mounting seats of the upper part, the lower part, the left side and the right side of the stirring tank, and the sensor models are the same batch of products to ensure the consistency of performance, and the sampling time synchronization error is controlled within 1ms; the control unit is provided with a signal consistency analysis module, which identifies external interference by calculating the waveform similarity and phase difference of the four vibration signals; when a single peak pulse appears in a certain signal and the other three signals have no synchronous response, or the correlation coefficient of the four signals suddenly drops below 0.6 (preset threshold), it is determined that there is non-material impact interference of the external environment; when significant external interference is detected, the control unit automatically starts the adaptive filter, which uses the least mean square algorithm (the algorithm adjusts the filter coefficient through continuous iteration to minimize the mean square error of the output signal and the expected signal), and dynamically adjusts the filter coefficient with the characteristic frequency of the interference signal as the reference. For example, if it is identified that the interference comes from the 50Hz power frequency component of the equipment vibration, the filter will specifically attenuate the signal energy of this frequency band; if the disturbance is a sudden impact, the cutoff frequency of the low-pass filter is temporarily increased to retain the effective signal. The vibration signal after filtering is used to generate the vibration energy sequence, ensuring that the sequence can truly reflect the aggregate collision state. By using the technical scheme, the combination scheme of multi-sensor comparison and adaptive filtering is adopted, and the effective vibration generated by the material collision and the external environmental interference are effectively distinguished, and the problem that a single sensor is easily affected by local interference is avoided. Even in the complex environment of equipment vibration, personnel collision and the like on the construction site, pure aggregate collision vibration signals can still be extracted, the correlation coefficient calculation is more reliable, and the anti-interference ability and stability of the adaptive shutdown control are improved.

[0022] According to a further embodiment of the application, the control unit is further configured to: establishing an aggregate collision vibration feature library, in which vibration spectrum features of typical aggregate collisions under different working conditions are stored; analyzing the transient features of the vibration signal in real time before generating the vibration energy sequence; when a transient event significantly deviating from the current aggregate collision feature library mode is detected in the vibration signal, it is determined as non-aggregate collision interference; Start the interference event filtering mechanism: when calculating the vibration energy sequence, the vibration data in the time period determined as the interference event is removed or significantly attenuated. The control unit prestores a library of aggregate collision vibration characteristics in the memory, which is constructed through a large number of experiments and contains typical vibration spectrum characteristics under different aggregate types (such as gravel, pebbles), particle size distribution (5-20mm) and stirring speed (10-40r / min), which is specifically manifested as the continuous energy distribution in the 100-800Hz frequency band and the peak value characteristics of the specific frequency. The transient feature analysis of the vibration signal is completed by the transient detection module of the control unit, which identifies abnormal transient events by calculating the kurtosis coefficient and short-time energy change rate of the signal. Before generating the vibration energy sequence, the transient detection module compares the spectrum characteristics of the current vibration signal with the patterns in the characteristic library in real time. When the vibration signal spectrum in a certain time period appears a narrow-band peak outside the characteristic library (such as a sudden high-frequency pulse above 2000Hz), or the kurtosis coefficient exceeds 3 times the normal range, it is determined as a non-aggregate collision interference (such as metal part friction, foreign matter falling). At this time, the control unit starts the interference event filtering mechanism, and when calculating the vibration energy sequence, the data in this time period is replaced with zero value or linear interpolation processing to eliminate the interference. By establishing the characteristic library and transient analysis, the embodiment of the application can accurately identify the vibration interference caused by non-aggregate collision, and compared with simple filtering processing, it more specifically excludes abnormal signals unrelated to material mixing. This makes the vibration energy sequence only reflect the true state of aggregate collision, ensures that the correlation analysis of the torque variation coefficient sequence is not disturbed, further improves the accuracy of the mixing endpoint judgment, and is especially suitable for the working conditions where impurities may be mixed in the raw materials or the equipment has a slight fault.

[0023] According to another embodiment of the application, a vibration signal preprocessing unit is further included, which is in signal connection with the vibration signal acquisition unit, and the vibration signal preprocessing unit: The environmental vibration spectrum is collected before the motor starts, the high-frequency narrow-band noise components greater than 500Hz in the environmental vibration are identified and recorded, and a high-frequency noise baseline model is established; The adaptive notch filter is applied to dynamically remove the coherent components; When the control unit extracts the aggregate collision vibration frequency band energy, the vibration signal after filtering is calculated; The high-frequency noise baseline module is automatically updated after each material emptying. The vibration signal preprocessing unit is connected with the vibration signal acquisition unit through a shielded cable, and includes a signal amplification circuit, a filtering module, and a baseline storage module. Before the motor is started, the preprocessing unit automatically enters an environmental vibration acquisition mode, acquires vibration signals for 10 seconds, and performs frequency spectrum analysis, identifies high-frequency narrow-band noise components (such as motor electromagnetic noise and sensor circuit noise) with a frequency greater than 500 Hz and an amplitude exceeding 3 times the background noise, stores the frequency and amplitude characteristics of these components in the baseline storage module, and forms a high-frequency noise baseline module. The adaptive notch filter is integrated in the filtering module, and according to the noise frequency in the baseline storage module, the notch filter parameters of the corresponding frequency are dynamically generated to attenuate the coherent high-frequency noise components in the vibration signal. For example, if the baseline module records narrow-band noise at 600 Hz and 1200 Hz, the filter will simultaneously suppress these two frequency points, and the attenuation amount is set to 30 dB. When the control unit extracts the aggregate collision vibration frequency band energy, it directly calculates based on the preprocessed vibration signal to ensure that the energy value is not disturbed by high-frequency noise; after each mixing is completed, when the discharge valve is completely opened and the material in the mixing tank is empty (detected by the weight sensor at the bottom of the tank), the preprocessing unit automatically starts the high-frequency noise baseline module update program, reacquires environmental vibration and updates the stored noise characteristics. By using the technical scheme, the high-frequency noise is eliminated, the noise energy is avoided from being mixed into the aggregate collision frequency band, the calculation of the vibration energy sequence is more accurate, reliable data basis is provided for subsequent correlation coefficient analysis, and the technical scheme is especially suitable for scenes where the noise characteristics of the equipment change after long-term use.

[0024] According to another embodiment of the application, the control unit further comprises a restart transient analysis module configured to perform the following operations: During each start of the motor, the vibration energy sequence and the torque variation coefficient sequence during the period from zero speed to stable speed are recorded in real time; The above two sequences are divided into continuous time segments, and the correlation coefficient of the two sequences in each time segment is calculated; The time required for the correlation coefficient to increase from the initial value to 90% of the stable value is determined as the material stick response time; According to the length of the stick response time, the torque variation coefficient data in the corresponding time period after the motor is started is marked as transition section data; In the calculation of the correlation coefficient sequence of the vibration energy sequence and the torque coefficient of variation sequence, the numerical values of the transition section data are weighted according to a preset rule: the longer the viscous response time, the lower the weighting proportion; the shorter the viscous response time, the higher the weighting proportion. The restart transient analysis module of the control unit is connected with the control loop and the sensor unit of the motor, and is automatically activated every time the motor starts. The module records the vibration energy sequence and the torque coefficient of variation sequence in real time from the start of the motor (the speed is 0) to the stable running speed, and the sampling interval is set to 0.5 seconds. Then, the module divides the two sequences into continuous 10-second time segments according to time, calculates the correlation coefficient of the two sequences in each segment, and forms the correlation coefficient change curve in the starting stage. The viscous response time is determined by analyzing the curve, specifically the time required for the correlation coefficient to grow from the initial value (usually close to 0) of the start to 90% of the average value of the correlation coefficient in the stable running stage. For example, if the average value of the correlation coefficient in the stable stage is 0.8, when the curve reaches 0.72, the corresponding time is the viscous response time, which is usually in the range of 15-60 seconds, affected by the initial moisture and viscosity of the material. According to the length of the viscous response time, the module marks the torque coefficient of variation data in the corresponding time period after the motor starts as transition section data, and performs weighted processing according to the preset rule: when the viscous response time is more than 40 seconds, the weighting proportion of the transition section data is 30%; within the range of 20-40 seconds, the weighting proportion is 50%; and below 20 seconds, the weighting proportion is 80%. With this technical solution, when calculating the correlation coefficient sequence of the vibration energy sequence and the torque coefficient of variation sequence, the control unit adjusts the transition section data according to the above weighting proportion, that is, the actual torque coefficient of variation value participating in the calculation is the original value multiplied by the weighting proportion. This processing method effectively reduces the influence of the material's viscous characteristics in the starting stage on the correlation analysis, avoids the low correlation coefficient caused by the distortion of the initial stage data, and makes the generation of the adaptive shutdown threshold more in line with the actual mixing process of the material, especially suitable for the mixing control of high-viscosity mortar.

[0025] According to another embodiment of the application, the control unit is configured with a segregation early warning module, which performs the following operations: In the stable mixing stage, the vibration sensor signals installed at three heights of the mixing tank are synchronously collected; The energy average values of the vibration signals at each height in the 50-1500 Hz aggregate collision frequency band are calculated respectively; Taking the middle energy value as the reference, the relative deviations of the upper and lower energy values from the middle are calculated: If the upper deviation is > +15% and the lower deviation is < -10%, it is determined that the aggregate is floating type segregation; If the lower deviation is > +15% and the upper deviation is < -10%, it is determined that the slurry is sinking type segregation; When segregation is detected, the stirring time is automatically extended based on the type of segregation, and a stepwise lifting program of the stirring shaft speed is triggered. Three vibration sensors are installed at the upper, middle and lower heights of the stirring tank, wherein the upper sensor is located at 80% of the height of the tank body, the middle sensor is located at 50%, and the lower sensor is located at 20%, all towards the material in the tank. The segregation early warning module of the control unit is connected with the three sensors, and the vibration signals thereof are synchronously collected in the stable stirring stage (after the motor reaches the stable speed). The segregation early warning module processes the three signals respectively, and calculates the average energy value (calculated every 10 seconds) of the aggregate collision frequency band of 50-1500Hz. Taking the energy value of the middle sensor as the reference, the relative deviations of the upper and lower energy values from the middle are calculated: if the upper deviation is greater than +15% and the lower deviation is less than -10%, it is determined that the segregation is the aggregate floating type; if the lower deviation is greater than +15% and the upper deviation is less than -10%, it is determined that the segregation is the slurry sinking type. When segregation is detected, the control unit automatically extends the stirring time (initially extended by 30 seconds, which can be stacked according to the segregation degree), and at the same time triggers the stepwise lifting program of the stirring shaft speed: each time the speed is increased by 5r / min, and the highest speed does not exceed 120% of the rated speed, and each speed level is maintained for 10 seconds. The preset rule adopts a linear weighting function, specifically: let the original torque variation coefficient at a certain time in the transition section be T, and the weighted value be T', then T'=T*K, wherein K is the weighting coefficient, and the relationship between the weighting coefficient K and the viscous response time t is a linear decay function: when t≤20 seconds, K=0.8; when 20 seconds

[0026] According to another embodiment of the present invention, an ambient temperature sensor is integrated on the outer wall of the mixing tank, and a material moisture content sensor is installed at the feeding port at the top of the tank (a Pt100 temperature sensor is integrated on the mounting base on the outer wall of the mixing tank, with a measurement range of -10℃ to 50℃ and an accuracy of ±0.5℃; a microwave moisture content sensor is installed at the feeding port at the top of the tank, which detects the material moisture content in a non-contact manner, with a measurement range of 5%-20% and an accuracy of ±0.5%); the control unit is configured to perform a dynamic reference calibration process. Preset standard operating condition parameter baseline values: temperature baseline value is 25℃, and moisture content baseline value is 10%. Real-time monitoring of ambient temperature sensor data and material moisture content sensor data; when real-time data deviates from the baseline value, compensation is performed according to the following rules: The temperature compensation mechanism lowers the threshold for determining the vibration energy sequence by 5% for every 5°C increase in ambient temperature above the reference value, and increases the threshold by 5% for every 5°C decrease in ambient temperature below the reference value. The humidity compensation mechanism lowers the adaptive shutdown threshold of the correlation coefficient sequence by 3% for every 1% increase in material moisture content above the benchmark value, and increases the adaptive shutdown threshold by 3% for every 1% decrease in material moisture content below the benchmark value. The compensation execution constraint stipulates that the adjustment range of a single compensation shall not exceed ±15% of the original threshold. When the ambient temperature or material moisture content returns to the benchmark value, the corresponding compensation mechanism is automatically released. When real-time data deviates from the benchmark value, compensation is performed according to the following rules: Temperature compensation mechanism: for every 5°C increase in ambient temperature above the benchmark value, the judgment threshold of the vibration energy sequence is reduced by 5%; for every 5°C decrease in ambient temperature below the benchmark value, the judgment threshold is increased by 5%. Humidity compensation mechanism: for every 1% increase in material moisture content above the benchmark value, the adaptive shutdown threshold of the correlation coefficient sequence is reduced by 3%; for every 1% decrease in material moisture content below the benchmark value, the adaptive shutdown threshold is increased by 3%. The compensation execution constraint stipulates that the adjustment range of a single compensation shall not exceed ±15% of the original threshold. When the ambient temperature or material moisture content returns to the benchmark value, the corresponding compensation mechanism is automatically released. By adopting this technical solution, this invention enables the system to adapt to the stirring requirements under different temperature and humidity conditions through dynamic compensation of environmental parameters, avoiding threshold setting deviations caused by environmental changes and ensuring accurate determination of the stirring endpoint under various operating conditions.

[0027] The number of devices and processing capacity described herein are for the purpose of simplifying the description of the invention. Applications, modifications, and variations of the concrete mortar mixing system of this invention will be readily apparent to those skilled in the art.

[0028] While embodiments of the application have been disclosed in connection with the above specification and drawings this description is not intended to limit the scope of the application and many modifications, enhancements, alternatives, and variations will become apparent to those skilled in the art from this disclosure. Accordingly, it is intended that the application not be limited to the described embodiments, but that it include all variations falling within the scope of the claims, and their equivalents.

Claims

1. A concrete mortar mixing system, characterized in that, include: A mixing tank is used to hold concrete mortar raw materials. The mixing tank is equipped with mixing blades, which are driven by a motor to mix. The vibration signal acquisition unit is installed on the outer wall of the mixing tank or on the mixing blades to capture the tank vibration signal in real time during the mixing process. A torque monitoring unit, which is connected to the motor output shaft, is used to detect torque changes during motor operation; The control unit, which is connected to both the vibration signal acquisition unit and the torque monitoring unit, is configured as follows: The vibration signal of the tank body is decomposed into a frequency domain signal, the energy value of the preset aggregate collision vibration frequency band is extracted and a vibration energy sequence is generated, the fluctuation intensity of the torque change is analyzed, a torque variation coefficient sequence is generated, and the correlation coefficient sequence between the vibration energy sequence and the torque variation coefficient sequence is calculated. During the initial stirring phase, an adaptive shutdown threshold is continuously generated using a sliding time window approach: continuous dynamic data windows are divided into durations of 30-120 seconds; the average value of the correlation coefficient within each data window is calculated. Calculate the standard deviation of the correlation coefficient within each data window as the fluctuation range; The adaptive shutdown threshold is set as: the average value of the current window minus the product of the preset sensitivity multiple and the fluctuation amplitude; the threshold is updated synchronously when the window data is updated; the preset sensitivity multiple is 1.5-3, and when the data points are less than 50% of the window capacity, a preset fixed threshold based on the current material formula is used. When the correlation coefficient sequence falls below the adaptive shutdown threshold for a preset number of consecutive times, the motor power is cut off.

2. The concrete mortar mixing system as described in claim 1, characterized in that, The control unit is further configured as follows: Monitor the speed of the motor; Identify the raw material feeding completion signal and use the raw material feeding completion signal as the starting point of the initial mixing stage; After the starting point, continuously monitor whether the motor speed reaches the preset stable operating speed; Once the motor reaches a stable operating speed and maintains it for a preset duration, the energy sequence and torque variation coefficient sequence are acquired and recorded. Based on the energy sequence and torque variation coefficient sequence recorded within the preset time period, the statistical characteristics of the correlation coefficient sequence are calculated, and the adaptive shutdown threshold is generated accordingly.

3. The concrete mortar mixing system as described in claim 1, characterized in that, The vibration signal acquisition unit includes multiple vibration sensors installed at different locations in the mixing tank; the control unit is further configured to: Based on signal consistency analysis from multiple vibration sensors, non-material impact interference originating from the external environment is identified. When significant external disturbances are detected, a vibration signal filtering mechanism is activated: an adaptive filter is used to suppress vibration components associated with external disturbances. The vibration energy sequence is regenerated based on the filtered vibration signal.

4. The concrete mortar mixing system as described in claim 3, characterized in that, The control unit is further configured to: Establish a vibration feature library for aggregate collisions, which stores the vibration spectrum features of typical aggregate collisions under different working conditions; Before generating the vibration energy sequence, the transient characteristics of the vibration signal are analyzed in real time; When a transient event that significantly deviates from the current aggregate collision feature library pattern is detected in the vibration signal, it is determined to be non-aggregate collision interference; Activate the interference event filtering mechanism: When calculating the vibration energy sequence, remove or significantly attenuate vibration data within the time period that is determined to be an interference event.

5. The concrete mortar mixing system as described in claim 1, characterized in that, It also includes a vibration signal preprocessing unit, which is connected to the vibration signal acquisition unit. The vibration signal preprocessing unit includes: Before the motor starts, the ambient vibration spectrum is collected, the high-frequency narrowband noise component greater than 500Hz in the ambient vibration is identified and recorded, and a high-frequency noise baseline mode is established. An adaptive notch filter is used to dynamically remove coherent components; When the control unit extracts the energy of the aggregate collision vibration frequency band, it calculates based on the filtered vibration signal. The high-frequency noise baseline mode is automatically updated after each material is emptied.

6. The concrete mortar mixing system as described in claim 5, characterized in that, The control unit also includes a restart transient analysis module, configured to perform the following operations: During each motor start-up process, the vibration energy sequence and torque variation coefficient sequence during the period from zero speed to stable speed are recorded in real time; Divide the two sequences into consecutive time segments and calculate the correlation coefficient between the two sequences within each time segment; The time required for the correlation coefficient to increase from its initial value to 90% of its stable value is determined as the material viscous response time. Based on the length of the viscous response time, the torque variation coefficient data within the corresponding time period after the motor starts is marked as transition zone data; When calculating the correlation coefficient between the vibration energy sequence and the torque coefficient of variation sequence, the values ​​of the transition section data are weighted according to a preset rule: the longer the viscous response time, the lower the weighting ratio; the shorter the viscous response time, the higher the weighting ratio.

7. The concrete mortar mixing system as described in claim 1, characterized in that, The control unit is configured with a segregation early warning module and performs the following operations: During the stable mixing phase, vibration sensor signals installed at three heights (top, middle, and bottom) of the mixing tank are collected simultaneously. Calculate the average energy of vibration signals at each height in the aggregate collision frequency band of 50-1500Hz; Using the energy value of the middle section as a benchmark, calculate the relative deviations between the energy values ​​of the upper and lower sections and the middle section: If the upper deviation is greater than +15% and the lower deviation is less than -10%, it is judged as aggregate floating segregation; If the lower deviation is greater than +15% and the upper deviation is less than -10%, it is judged as segregation due to slurry settling. When segregation is detected, the stirring time is automatically extended based on the segregation type, triggering a step-by-step increase in the stirring shaft speed.

8. The concrete mortar mixing system as described in claim 1, characterized in that, An ambient temperature sensor is integrated into the outer wall of the mixing tank, and a material moisture content sensor is installed at the feeding port on the top of the tank; the control unit is configured to perform a dynamic benchmark calibration process. Preset standard operating condition parameter baseline values: temperature baseline value is 25℃, and moisture content baseline value is 10%. Real-time monitoring of ambient temperature sensor data and material moisture content sensor data; when real-time data deviates from the baseline value, compensation is performed according to the following rules: The temperature compensation mechanism lowers the threshold for determining the vibration energy sequence by 5% for every 5°C increase in ambient temperature above the reference value, and increases the threshold by 5% for every 5°C decrease in ambient temperature below the reference value. The humidity compensation mechanism lowers the adaptive shutdown threshold of the correlation coefficient sequence by 3% for every 1% increase in material moisture content above the benchmark value, and increases the adaptive shutdown threshold by 3% for every 1% decrease in material moisture content below the benchmark value. The compensation execution is constrained, and the adjustment range of a single compensation shall not exceed ±15% of the original threshold. When the ambient temperature or the moisture content of the material returns to the benchmark value, the corresponding compensation mechanism will be automatically released.

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