Surface dust removal control system for powder compression molding

Abstract

The invention relates to the technical field of dust removal control, in particular to a surface dust removal control system for powder compression molding, which comprises a dust removal control module, a dust feature acquisition module, a dust removal performance judgment module, a dust removal working condition acquisition module, a dust removal working condition judgment module and a dust removal process correction module, the dust characteristic acquisition module acquires wall surface shear force, purging coverage rate and airflow dead zone residual value in a powder compression molding demolding purging period, and analyzes dust particle size characteristic characterization value; the dust removal performance judgment module determines whether the momentum transfer effectiveness of the dust removal pulse injection device meets the standard or not; in response to the non-compliance with the standard, the dust removal working condition acquisition module acquires the airflow pressure attenuation rate and the local airflow backflow amplitude in the same purging period, and analyzes the feature representation value of the dust removal pulse valve; the dust removal working condition judgment module determines whether the stability of the airflow pressure field of the dust removal pulse injection device meets the standard or not so as to determine a treatment strategy. The surface dust removal control efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of dust control technology, and in particular to a surface dust control system for powder pressing and molding. Background Technology

[0002] In powder molding, residual powder often adheres to the surface of the target product after demolding, requiring cleaning via air-blowing dust removal to ensure product surface quality and the reliability of subsequent processing steps. Existing air-blowing dust removal systems typically operate with preset fixed blowing parameters, including fixed air pressure, fixed pulse count, and fixed blowing time. They lack the ability to monitor and adjust the actual blowing effect in real time throughout the production cycle. In actual production, product surface morphology is complex and variable, with differences in dust particle size. Fluctuations in air source pressure, nozzle wear, and pipeline blockages can also cause the actual blowing state to deviate from the initial settings. Because current technology cannot obtain dust particle size data in real time, when problems such as incomplete dust removal, blind spots in blowing coverage, and residual dust in airflow dead zones occur, it is difficult to accurately determine whether the root cause of poor dust removal is insufficient blowing strategy or abnormal airflow performance. That is, it is impossible to distinguish whether the problem originates from insufficient pulse count, excessive pressure attenuation, or uneven airflow distribution. Often, empirical and blind parameter adjustments are adopted, leading to recurring problems and poor process stability, ultimately affecting product molding quality and the processing effect of subsequent steps.

[0003] Chinese Patent Publication No. CN119634729A discloses an air-blowing demolding device and method for powder metallurgy products. The device includes a support base, with the output end of a motor connected to a first bevel gear. An air-blowing mechanism is fixed to one side of the support base and meshes with the bottom of the first bevel gear. After the injection molding operation is completed, the second piston, moving frame, and sealing plug move downwards to facilitate connection between the mold pipe and the air-blowing channel. Simultaneously, the turntable rotates, and all the extrusion blocks alternately extrude the pull rod. The movable frame, pull rod, and striking block move back and forth under the extrusion of the extrusion blocks and the support of the second compression spring, facilitating repeated striking of the mold pipe to completely separate the product from the inner wall of the mold pipe for subsequent rapid demolding. The air-blowing channel automatically blows air upwards to achieve automatic demolding and prevent product damage.

[0004] Chinese Patent Publication No. CN114101216A discloses an automatic micro-atomized programmed automatic cleaning mechanism for an automatic powder forming press mold, comprising: a mounting plate and a housing, the housing being fixedly connected to the mounting plate; a dust removal mechanism connected to the housing; and an atomizing air blowing mechanism located outside and connected to the dust removal mechanism. The dust removal mechanism includes: a dust suction component located outside the housing; a rotary connecting component located between the dust suction component and the housing; and a dust removal pressurizing component located inside the housing and connected to the rotary connecting component. By combining the dust removal mechanism and the atomizing air blowing mechanism, the mechanism can not only clean the dust located inside the mold but also recycle the dust. Summary of the Invention

[0005] To address this, the present invention provides a surface dust removal control system for powder pressing molding, which overcomes the problems in the prior art where the dust removal airflow for powder pressing molding is difficult to adapt to the complex surface morphology of the product, and cannot distinguish whether the momentum transfer effectiveness and the stability of the airflow pressure field meet the process requirements, resulting in insufficient dust removal from the wall, blind spots in the blowing coverage, and residual dust in the airflow dead zone, thus reducing the surface dust removal control efficiency.

[0006] To achieve the aforementioned objective, the present invention provides a surface dust removal control system for powder pressing and molding, comprising: Dust control module, used for air blowing dust control on the surface of the target product during the powder pressing and demolding process; The dust feature acquisition module is used to acquire dust particle size characteristic parameters during the powder pressing, molding, demolding, and blowing cycle; and to analyze the dust particle size characteristic values ​​based on the dust particle size characteristic parameters. The dust removal performance determination module is used to determine whether the momentum transfer effectiveness of the dust removal pulse jet device meets the standard based on the comparison result between the dust particle size characteristic characterization value and the dust particle size characteristic characterization threshold. The dust removal operating condition acquisition module is used to collect characteristic parameters of the dust removal pulse valve within the same purging cycle in response to the fact that the momentum transfer effectiveness of the dust removal pulse jet device does not meet the standard; and to analyze the characteristic value of the dust removal pulse valve based on the characteristic parameters of the dust removal pulse valve. The dust removal operating condition determination module is used to determine whether the airflow pressure field stability of the dust removal pulse valve meets the standard based on the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve. The dust removal process correction module is used to respond to the fact that the airflow pressure field stability of the dust removal pulse jet device meets the standard. If it is determined that the momentum transfer of the dust removal pulse jet device is insufficient to cope with complex surfaces, the number of pulses will be increased. In response to the fact that the airflow pressure field stability of the dust removal pulse jet device does not meet the standard, the adjustment range of the nozzle outlet flow rate distribution is determined based on the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve. The dust particle size characteristic parameters include wall shear force, purging coverage, and residual value of airflow dead zone; The characteristic parameters of the dust removal pulse valve include airflow pressure attenuation rate and local airflow backflow amplitude.

[0007] Furthermore, the dust feature acquisition module analyzes the dust particle size characteristic value and determines it based on the sum of the first characteristic limiting parameter, the second characteristic limiting parameter, and the third characteristic limiting parameter, wherein, The first feature defines the characterization parameter as the ratio of wall shear force to a predetermined wall shear force threshold. The second feature defines the characterization parameter as the ratio of the purge coverage rate to a predetermined purge coverage rate threshold; The third feature defines the characterization parameter as the ratio of a predetermined airflow dead zone residual value threshold to the airflow dead zone residual value.

[0008] Furthermore, the dust removal performance determination module is used to determine the condition that the momentum transfer effectiveness of the dust removal pulse jet device meets the standard: the dust particle size characteristic value is greater than the dust particle size characteristic threshold.

[0009] Furthermore, the dust removal performance determination module is used to determine the condition that the momentum transfer effectiveness of the dust removal pulse jet device does not meet the standard: the dust particle size characteristic characterization value is less than or equal to the dust particle size characteristic characterization threshold.

[0010] The dust removal operating condition acquisition module is used to analyze the characteristic values ​​of the dust removal pulse valve, which are determined based on the sum of the first operating condition limiting characteristic parameters and the second operating condition limiting characteristic parameters. The first operating condition is defined by the ratio of the airflow pressure attenuation rate to a predetermined airflow pressure attenuation rate threshold. The second operating condition is defined by the ratio of the local airflow recirculation amplitude to a predetermined local airflow recirculation amplitude threshold.

[0011] Furthermore, the dust removal condition determination module determines that the airflow pressure field stability of the dust removal pulse jet device meets the standard when the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve is less than the predetermined difference threshold.

[0012] Furthermore, the dust removal condition determination module determines that the condition under which the airflow pressure field stability of the dust removal pulse jet device does not meet the standard is that the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve is greater than or equal to the predetermined difference threshold.

[0013] Furthermore, the dust removal process correction module determines that the condition for increasing the number of pulses is that the airflow pressure field stability of the dust removal pulse jet device meets the standard.

[0014] Furthermore, the condition for the dust removal process correction module to determine the adjustment range of the nozzle outlet airflow distribution is that the airflow pressure field stability of the dust removal pulse jet device does not meet the standard.

[0015] Furthermore, the dust removal process correction module determines the adjustment range of the nozzle outlet airflow distribution based on the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention provides a surface dust removal control system for powder pressing molding, including: a dust removal control module, a dust feature acquisition module, a dust removal performance determination module, a dust removal working condition acquisition module, a dust removal working condition determination module, and a dust removal process correction module. The dust removal control module is used for air blowing dust removal control of the target product surface in the powder pressing molding demolding process; the dust feature acquisition module is used to acquire the wall shear force, blowing coverage, and airflow dead zone residue value during the powder pressing molding demolding blowing cycle, thereby analyzing the dust particle size characteristic value; the dust removal performance determination module is used to determine whether the momentum transfer effectiveness of the dust removal pulse jet blowing device meets the standard based on the comparison result of the dust particle size characteristic value and the dust particle size characteristic threshold, and can quantitatively identify the airflow dead zone residue and local insufficient coverage problems caused by the complex surface morphology of the product. In response to the dust removal pulse jet cleaning device's momentum transfer effectiveness not meeting the standard, the dust removal condition acquisition module collects the airflow pressure attenuation rate and local airflow backflow amplitude within the same purging cycle; it analyzes the characteristic values ​​of the dust removal pulse valve based on the characteristic parameters of the dust removal pulse valve; the dust removal condition judgment module determines whether the airflow pressure field stability of the dust removal pulse jet cleaning device meets the standard based on the difference between the characteristic values ​​of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve, thus realizing independent diagnosis of the air source supply capacity and pipeline transmission status; in response to the dust removal pulse jet cleaning device's airflow pressure field stability meeting the standard, the dust removal process correction module determines that the airflow coverage capacity of the dust removal control module is insufficient to cope with complex surfaces and determines to increase the number of pulses; in response to the dust removal pulse jet cleaning device's airflow pressure field stability not meeting the standard, it determines the adjustment range of the nozzle outlet airflow distribution. By performing stratified judgment and diagnosis of momentum transfer effectiveness and airflow pressure field stability, the cause of dust removal failure was accurately located. Corresponding process correction methods were matched according to the fault type. This ensured the dust removal effect on the complex surface of powder-pressed products while avoiding energy waste and product surface impact damage caused by blindly increasing pressure. It also improved the consistency and process stability of surface dust removal in the demolding process.

[0017] In particular, by ratioing the wall shear force, purging coverage, and residual value of the airflow dead zone to their respective predetermined thresholds and summing them to obtain the dust particle size characteristic value, a normalized fusion of the three dimensions of airflow stripping intensity, spatial coverage, and local cleaning blind zone is achieved, overcoming the difficulty of comprehensively characterizing purging uniformity with a single parameter. The relationship between the dust particle size characteristic value and the preset threshold is used as the quantitative criterion for determining whether the momentum transfer effectiveness of the dust removal pulse jet device is qualified. When the characteristic value is greater than the threshold, the momentum transfer effectiveness is determined to be qualified; when the characteristic value is less than or equal to the threshold, the momentum transfer effectiveness is determined to be unqualified, triggering the subsequent stratified diagnostic process. This ensures the accuracy of multi-dimensional comprehensive evaluation while ensuring that secondary acquisition and diagnosis are only initiated when the momentum transfer effectiveness is unqualified, avoiding unnecessary consumption of system resources.

[0018] In particular, by ratioing the airflow pressure attenuation rate and the local airflow backflow amplitude to their respective predetermined thresholds, and summing the two, the characteristic value of the dust removal pulse valve is obtained. The airflow pressure attenuation rate reflects the degree of pressure loss from the air source to the nozzle outlet, and the local airflow backflow amplitude characterizes the backflow intensity of the airflow caused by the abrupt change in morphology between the nozzle and the complex surface of the product. The comparison between the characteristic value of the dust removal pulse valve and the predetermined threshold and the difference threshold is used as the quantitative judgment basis for whether the airflow pressure field stability of the dust removal pulse jet device is qualified. When the difference is less than the difference threshold, the airflow pressure field stability is judged to meet the standard. When the difference is greater than or equal to the difference threshold, the airflow pressure field stability is judged to not meet the standard.

[0019] In particular, when the airflow pressure field stability meets the standard, it indicates that the momentum transfer effectiveness is not up to standard due to insufficient airflow coverage. In this case, the number of pulses is increased to enhance the dynamic coverage effect of complex surfaces through multiple intermittent impacts. When the airflow pressure field stability does not meet the standard, it indicates that the air supply capacity is insufficient or the pipeline pressure drop is too large. In this case, the adjustment range of the nozzle outlet flow distribution is determined to optimize the airflow supply from the source. The adjustment range of the outlet flow distribution is quantitatively determined based on the difference between the characteristic value of the dust removal pulse valve and the predetermined threshold, so that the correction amount matches the actual deviation and avoids the problem of insufficient or excessive correction caused by fixed step size adjustment. Attached Figure Description

[0020] Figure 1 This is a structural block diagram of the surface dust removal control system for powder pressing molding according to an embodiment of the present invention; Figure 2 This is a flowchart illustrating the steps of the surface dust removal control method for powder pressing molding according to an embodiment of the present invention. Figure 3This is a logic diagram for determining whether the momentum transfer effectiveness of the dust removal pulse jet cleaning device meets the standard in an embodiment of the present invention. Figure 4 This is a logic diagram for determining whether the airflow pressure field stability of the dust removal pulse jet cleaning device meets the standard in an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0022] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0023] Please see Figure 1 The diagram shown is a structural block diagram of a surface dust removal control system for powder pressing molding according to an embodiment of the present invention. The present invention provides a surface dust removal control system for powder pressing molding, comprising: Dust control module, used for air blowing dust control on the surface of the target product during the powder pressing and demolding process; The dust removal feature acquisition module is used to acquire dust particle size characteristic parameters during the powder pressing, molding, demolding, and blowing cycle; and to analyze the dust particle size characteristic values ​​based on the dust particle size characteristic parameters. The dust removal performance determination module is used to determine whether the momentum transfer effectiveness of the dust removal pulse jet device meets the standard based on the comparison result between the dust particle size characteristic characterization value and the dust particle size characteristic characterization threshold. The dust removal operating condition acquisition module is used to collect characteristic parameters of the dust removal pulse valve within the same purging cycle in response to the fact that the momentum transfer effectiveness of the dust removal pulse jet device does not meet the standard; and to analyze the characteristic value of the dust removal pulse valve based on the characteristic parameters of the dust removal pulse valve. The dust removal operating condition determination module is used to determine whether the airflow pressure field stability of the dust removal pulse valve meets the standard based on the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve. The dust removal process correction module is used to respond to the fact that the airflow pressure field stability of the dust removal pulse jet device meets the standard. If it is determined that the momentum transfer of the dust removal pulse jet device is insufficient to cope with complex surfaces, the number of pulses will be increased. In response to the fact that the airflow pressure field stability of the dust removal pulse jet device does not meet the standard, the adjustment range of the nozzle outlet flow rate distribution is determined based on the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve. The dust particle size characteristic parameters include wall shear force, purging coverage, and residual value of airflow dead zone; The characteristic parameters of the dust removal pulse valve include airflow pressure attenuation rate and local airflow backflow amplitude.

[0024] In this embodiment, the present invention provides a surface dust removal control system for powder pressing molding, including: a dust removal control module, a dust feature acquisition module, a dust removal performance judgment module, a dust removal working condition acquisition module, a dust removal working condition judgment module, and a dust removal process correction module. The dust removal control module is used for air blowing dust removal control of the target product surface during the powder pressing molding demolding process; the dust feature acquisition module is used to acquire the wall shear force, blowing coverage, and airflow dead zone residue value during the powder pressing molding demolding blowing cycle, thereby analyzing the dust particle size characteristic value; the dust removal performance judgment module is used to determine whether the momentum transfer effectiveness of the dust removal pulse jet device meets the standard based on the comparison result of the dust particle size characteristic value and the dust particle size characteristic threshold, and can quantitatively identify the airflow dead zone residue and local insufficient coverage problems caused by the complex surface morphology of the product; responding to the dust removal pulse... If the momentum transfer effectiveness of the pulse jet cleaning device does not meet the standard, the dust removal condition acquisition module collects the airflow pressure attenuation rate and local airflow backflow amplitude within the same purging cycle; it analyzes the characteristic values ​​of the dust removal pulse valve based on the characteristic parameters of the dust removal pulse valve; the dust removal condition judgment module determines whether the airflow pressure field stability of the dust removal pulse jet cleaning device meets the standard based on the difference between the characteristic values ​​of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve, thus realizing independent diagnosis of the air supply capacity and pipeline transmission status; if the airflow pressure field stability of the dust removal pulse jet cleaning device meets the standard, the dust removal process correction module determines that the airflow coverage capacity of the dust removal control module is insufficient to cope with complex surfaces and determines to increase the number of pulses; if the airflow pressure field stability of the dust removal pulse jet cleaning device does not meet the standard, it determines the adjustment range of the nozzle outlet flow rate distribution. By performing stratified judgment and diagnosis of momentum transfer effectiveness and airflow pressure field stability, the cause of dust removal failure was accurately located. Corresponding process correction methods were matched according to the fault type. This ensured the dust removal effect on the complex surface of powder-pressed products while avoiding energy waste and product surface impact damage caused by blindly increasing pressure. It also improved the consistency and process stability of surface dust removal in the demolding process.

[0025] Please see Figure 2 The diagram shown is a flowchart illustrating the steps of a surface dust control method for powder pressing molding according to an embodiment of the present invention. The present invention provides a surface dust control method for powder pressing molding, comprising: Step S1: Collect the dust particle size characteristic parameters during the powder compression molding demolding and blowing cycle; analyze the dust particle size characteristic value based on the dust particle size characteristic parameters; Step S2: Based on the comparison results between the dust particle size characteristic characterization value and the dust particle size characteristic characterization threshold, determine whether the momentum transfer effectiveness of the dust removal pulse jet device meets the standard; Step S3: In response to the fact that the momentum transfer effectiveness of the dust removal pulse jet device does not meet the standard, collect the characteristic parameters of the dust removal pulse valve within the same purging cycle; and analyze the characteristic value of the dust removal pulse valve based on the characteristic parameters of the dust removal pulse valve. Step S4: Determine whether the airflow pressure field stability of the dust removal pulse valve meets the standard based on the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve. Step S5: In response to the fact that the airflow pressure field stability of the dust removal pulse jet device meets the standard, it is determined that the momentum transfer of the dust removal pulse jet device is insufficient to cope with complex surfaces, and it is determined to increase the number of pulses. Step S6: In response to the fact that the airflow pressure field stability of the dust removal pulse jet device does not meet the standard, the adjustment range of the nozzle outlet flow rate distribution is determined based on the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve. The dust particle size characteristic parameters include wall shear force, purging coverage, and residual value of airflow dead zone; The characteristic parameters of the dust removal pulse valve include airflow pressure attenuation rate and local airflow backflow amplitude.

[0026] Understandably, wall shear force refers to the tangential force exerted by the airflow on a unit area of ​​the product surface under the action of the purge airflow. During measurement, a total pressure sensor is installed at the outlet of the purge nozzle, and a MEMS static pressure sensor is embedded at a key location on the target product surface. Based on a flat-plate jet wall shear force model, the force is calculated from the measured pressure value and preset nozzle angle and distance. The calculation is based on the following relationship: the wall shear force is equal to half the product of the local friction coefficient, air density, and the square of the near-wall velocity, where the near-wall velocity is derived from the nozzle outlet pressure.

[0027] As can be understood, the purging coverage rate refers to the proportion of the area actually covered by the purging airflow on the target product surface to the total area to be dusted. During measurement, a high-speed industrial camera is used to capture the coverage pattern of the airflow on the product surface during the purging process, and the outline of the covered area is extracted through image processing.

[0028] As can be understood, the airflow dead zone residual value refers to the proportion of the area on the target product surface where dust remains due to the ineffective action of airflow after purging, relative to the total area to be cleaned. During measurement, the same high-speed industrial camera images the product after purging, and the residual area is extracted using a dust residue recognition algorithm.

[0029] As can be understood, the airflow pressure attenuation rate refers to the degree to which the pressure decreases along the path of the airflow as it is delivered from the dust collector pulse valve outlet to the purge nozzle, reflecting the energy loss characteristics of the airflow transmission channel. During measurement, pressure sensors at the dust collector pulse valve outlet and the purge nozzle inlet are simultaneously collected; the calculation basis is: the airflow pressure attenuation rate equals the absolute value of the difference between the nozzle inlet pressure and the valve outlet pressure divided by the valve outlet pressure.

[0030] It is understandable that the local airflow backflow amplitude refers to the intensity of airflow reversal in a localized area during the purging process due to abrupt changes in the product surface structure or uneven airflow organization, reflecting the degree of local instability in the airflow pressure field. During measurement, pressure sensors are placed in areas on the target product surface prone to backflow to collect airflow direction and velocity fluctuations; the calculation is based on the ratio of the hourly average velocity of the reverse airflow to the velocity of the forward mainstream airflow.

[0031] In this embodiment, the purging cycle refers to the time interval from the start to the stop of the purging airflow during a complete purging dust removal process performed by the dust removal control module; the cycle includes the number of pulses, the duration of a single pulse, and the pulse interval.

[0032] In this embodiment, the purging cycle is set according to the surface complexity and dust adhesion characteristics of the target product. The purging cycle is [3 seconds, 15 seconds], and preferably 8 seconds in this embodiment; the number of pulses within the purging cycle is [3 times, 10 times], and preferably 5 times in this embodiment; the duration of a single pulse is [0.5 seconds, 2 seconds], and preferably 1 second in this embodiment; the pulse interval is [0.3 seconds, 1 second], and preferably 0.5 seconds in this embodiment.

[0033] In this embodiment, the three processes of pressing, demolding, and purging are controlled by time-coupling. The purging process starts synchronously when the demolding stroke reaches the preset threshold position and gradually covers the entire surface of the product as the demolding process progresses. The purging cycle is set from the start of purging to the completion of demolding, plus an additional 2 seconds of continuous purging. The pulse frequency is related to the demolding stroke. Before 70% of the demolding is completed, low-frequency pulses are used to avoid dust being pressed back in. Afterward, high-frequency pulses are switched to enhance the coverage effect, thereby achieving dynamic matching between the purging airflow and the demolding process.

[0034] Furthermore, the dust removal feature acquisition module analyzes the dust particle size characteristic value and determines it based on the sum of the first characteristic limiting parameter, the second characteristic limiting parameter, and the third characteristic limiting parameter, wherein, The first feature defines the characterization parameter as the ratio of wall shear force to a predetermined wall shear force threshold. The second feature defines the characterization parameter as the ratio of the purge coverage rate to a predetermined purge coverage rate threshold; The third feature defines the characterization parameter as the ratio of a predetermined airflow dead zone residual value threshold to the airflow dead zone residual value.

[0035] In this embodiment, the predetermined wall shear force threshold refers to the minimum wall shear force required to effectively peel off the attached dust, which is obtained through experimental calibration; the predetermined purging coverage threshold refers to the lower limit of the effective coverage area of ​​the airflow required to ensure the overall cleaning effect, which is set according to the complexity of the product shape; the predetermined airflow dead zone residual value threshold refers to the upper limit of the maximum amount of dust residue allowed to ensure product quality, which is determined according to the cleanliness requirements.

[0036] Please see Figure 3 As shown, this is a logic diagram for determining whether the momentum transfer effectiveness of the dust removal pulse jet cleaning device meets the standard according to an embodiment of the present invention. The process for determining whether the momentum transfer effectiveness of the dust removal pulse jet cleaning device meets the standard according to the present invention includes: The comparison results of the extracted dust particle size characteristic values ​​with the predetermined dust particle size characteristic threshold are obtained. If the dust particle size characteristic value is greater than the predetermined dust particle size characteristic threshold, then the momentum transfer effectiveness of the dust removal pulse jet device is determined to meet the standard. If the dust particle size characteristic value is less than or equal to the predetermined dust particle size characteristic threshold, then the momentum transfer effectiveness of the dust removal pulse jet device is determined to be non-compliant with the standard.

[0037] In this embodiment, the predetermined dust particle size characteristic characterization threshold is obtained in advance. All dust particle size characteristic characterization values ​​are collected during the powder pressing, molding, demolding, and blowing cycle, and their average value is calculated. The predetermined dust particle size characteristic characterization threshold is selected within the range [3.05, 3.35] in this embodiment. Preferably, the predetermined dust particle size characteristic characterization threshold is 3.15.

[0038] In this embodiment, by ratioing the wall shear force, purging coverage, and residual value of the airflow dead zone to their respective predetermined thresholds and summing them to obtain the dust particle size characteristic value, a normalized fusion of the three dimensions of airflow stripping intensity, spatial coverage, and local cleaning blind zone is achieved, overcoming the difficulty of comprehensively characterizing the uniformity of purging with a single parameter. The relationship between the dust particle size characteristic value and the preset threshold is used as the quantitative judgment basis for whether the momentum transfer effectiveness of the dust removal pulse jet device is qualified. When the characteristic value is greater than the threshold, the momentum transfer effectiveness is judged to be qualified; when the characteristic value is less than or equal to the threshold, the momentum transfer effectiveness is judged to be unqualified, triggering the subsequent hierarchical diagnosis process. This ensures the accuracy of multi-dimensional comprehensive evaluation while ensuring that secondary acquisition and diagnosis are only initiated when the momentum transfer effectiveness is unqualified, avoiding unnecessary consumption of system resources.

[0039] Specifically, the dust removal operating condition acquisition module is used to analyze the characteristic values ​​of the dust removal pulse valve, which are determined based on the sum of the first operating condition limiting characteristic parameters and the second operating condition limiting characteristic parameters, wherein... The first operating condition is defined by the ratio of the airflow pressure attenuation rate to a predetermined airflow pressure attenuation rate threshold. The second operating condition is defined by the ratio of the local airflow recirculation amplitude to a predetermined local airflow recirculation amplitude threshold.

[0040] In this embodiment, the predetermined airflow pressure attenuation rate threshold refers to the upper limit of the maximum pressure loss rate allowed to ensure sufficient impact pressure at the nozzle outlet, which is obtained through calculation and calibration based on the pipeline system design parameters and the minimum outlet pressure required by the process; the predetermined local airflow backflow amplitude threshold refers to the upper limit of the maximum backflow intensity allowed to ensure stable airflow at complex surfaces, which is obtained based on product morphology characteristics and flow field simulation calibration; the two thresholds define the qualified boundaries of airflow supply performance from the two dimensions of delivery efficiency and flow stability, respectively.

[0041] Please see Figure 4 As shown, this is a logic diagram for determining whether the airflow pressure field stability of the dust removal pulse jet cleaning device meets the standard according to an embodiment of the present invention. The process for determining whether the airflow pressure field stability of the dust removal pulse jet cleaning device meets the standard includes: Calculate the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve; If the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve is less than the predetermined difference threshold, then the airflow pressure field stability of the dust removal pulse jet device is determined to meet the standard. If the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve is greater than or equal to the predetermined difference threshold, then the airflow pressure field stability of the dust removal pulse jet device is determined to be non-compliant with the standard.

[0042] In this embodiment, the predetermined threshold value for the dust removal pulse valve is obtained in advance. All characteristic values ​​of the dust removal pulse valve are collected and the average value is calculated. The predetermined threshold value for the dust removal pulse valve is selected within the range [1.95, 2.35]. Preferably, the predetermined threshold value for the dust removal pulse valve is 2.15.

[0043] In this embodiment, the predetermined difference threshold is obtained in advance. All differences between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve within the same purging cycle are calculated, and their average value is calculated. In this embodiment, the predetermined difference threshold is selected within the range [0.05, 0.35]. Preferably, the predetermined difference threshold is 0.15.

[0044] By ratioing the airflow pressure attenuation rate and the local airflow backflow amplitude to their respective predetermined thresholds, and summing the two, the characteristic value of the dust removal pulse valve is obtained. The airflow pressure attenuation rate reflects the degree of pressure loss from the air source to the nozzle outlet, and the local airflow backflow amplitude characterizes the backflow intensity caused by the abrupt change in morphology between the nozzle and the complex surface of the product. The comparison between the characteristic value of the dust removal pulse valve and the predetermined threshold and the difference threshold is used as the quantitative judgment basis for whether the airflow pressure field stability of the dust removal pulse jet device is qualified. When the difference is less than the difference threshold, the airflow pressure field stability is judged to meet the standard. When the difference is greater than or equal to the difference threshold, the airflow pressure field stability is judged to not meet the standard.

[0045] Specifically, the dust removal process correction module determines that the condition for increasing the number of pulses is that the airflow pressure field stability of the dust removal pulse jet device meets the standard.

[0046] In the embodiment, when the stability of the airflow pressure field meets the standard, it indicates that the reason for the failure of momentum transfer effectiveness is insufficient airflow coverage. At this time, the number of pulses is increased, and the dynamic coverage effect of the complex surface is enhanced by multiple intermittent impacts.

[0047] Specifically, the condition for the dust removal process correction module to determine the adjustment range of the nozzle outlet flow distribution is that the airflow pressure field stability of the dust removal pulse jet device does not meet the standard.

[0048] In the embodiment, when the stability of the airflow pressure field does not meet the standard, it indicates that the air supply capacity is insufficient or the pipeline pressure drop is too large. At this time, the adjustment range of the nozzle outlet flow distribution is determined to optimize the airflow supply from the source.

[0049] Specifically, the dust removal process correction module determines the adjustment range of the nozzle outlet flow distribution based on the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve.

[0050] In this embodiment, the adjustment range of the exhaust flow distribution is quantitatively determined by the difference between the characteristic value of the dust removal pulse valve and a predetermined threshold. The larger the difference, the larger the adjustment range, so that the correction amount matches the actual deviation and avoids the problem of insufficient or excessive correction caused by fixed step size adjustment.

[0051] The technical solution of the present invention has been described in conjunction with the embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to the specific implementation methods of the embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A surface dust removal control system for powder pressing and molding, characterized in that, include: Dust control module, used for air blowing dust control on the surface of the target product during the powder pressing and demolding process; The dust feature acquisition module is used to acquire dust particle size characteristic parameters during the powder pressing, molding, demolding, and blowing cycle; and to analyze the dust particle size characteristic values ​​based on the dust particle size characteristic parameters. The dust removal performance determination module is used to determine whether the momentum transfer effectiveness of the dust removal pulse jet device meets the standard based on the comparison result between the dust particle size characteristic characterization value and the dust particle size characteristic characterization threshold. The dust removal operating condition acquisition module is used to collect characteristic parameters of the dust removal pulse valve within the same purging cycle in response to the fact that the momentum transfer effectiveness of the dust removal pulse jet device does not meet the standard; and to analyze the characteristic value of the dust removal pulse valve based on the characteristic parameters of the dust removal pulse valve. The dust removal operating condition determination module is used to determine whether the airflow pressure field stability of the dust removal pulse valve meets the standard based on the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve. The dust removal process correction module is used to respond to the fact that the airflow pressure field stability of the dust removal pulse jet device meets the standard. If it is determined that the momentum transfer of the dust removal pulse jet device is insufficient to cope with complex surfaces, the number of pulses will be increased. In response to the fact that the airflow pressure field stability of the dust removal pulse jet device does not meet the standard, the adjustment range of the airflow distribution of the purging nozzle is determined based on the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve. The dust particle size characteristic parameters include wall shear force, purging coverage, and residual value of airflow dead zone; The characteristic parameters of the dust removal pulse valve include airflow pressure attenuation rate and local airflow backflow amplitude.

2. The surface dust removal control system for powder pressing and molding according to claim 1, characterized in that, The dust feature acquisition module analyzes the dust particle size characteristic value based on the sum of the first characteristic limiting parameter, the second characteristic limiting parameter, and the third characteristic limiting parameter, wherein, The first feature defines the characterization parameter as the ratio of wall shear force to a predetermined wall shear force threshold. The second feature defines the characterization parameter as the ratio of the purge coverage rate to a predetermined purge coverage rate threshold; The third feature defines the characterization parameter as the ratio of a predetermined airflow dead zone residual value threshold to the airflow dead zone residual value.

3. The surface dust removal control system for powder pressing and molding according to claim 2, characterized in that, The dust removal performance determination module is used to determine whether the momentum transfer effectiveness of the dust removal pulse jet device meets the standard condition that the dust particle size characteristic value is greater than the dust particle size characteristic threshold.

4. The surface dust removal control system for powder pressing and molding according to claim 3, characterized in that, The dust removal performance determination module is used to determine the condition that the momentum transfer effectiveness of the dust removal pulse jet device does not meet the standard: the dust particle size characteristic characterization value is less than or equal to the dust particle size characteristic characterization threshold.

5. The surface dust removal control system for powder pressing and molding according to claim 4, characterized in that, The dust removal operating condition acquisition module is used to analyze the characteristic values ​​of the dust removal pulse valve, which are determined based on the sum of the first operating condition limiting characteristic parameters and the second operating condition limiting characteristic parameters. The first operating condition is defined by the ratio of the airflow pressure attenuation rate to a predetermined airflow pressure attenuation rate threshold. The second operating condition is defined by the ratio of the local airflow recirculation amplitude to a predetermined local airflow recirculation amplitude threshold.

6. The surface dust removal control system for powder pressing and molding according to claim 5, characterized in that, The dust removal condition determination module determines that the airflow pressure field stability of the dust removal pulse jet device meets the standard when the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve is less than the predetermined difference threshold.

7. The surface dust removal control system for powder pressing and molding according to claim 6, characterized in that, The dust removal condition determination module determines that the condition under which the airflow pressure field stability of the dust removal pulse jet device does not meet the standard is that the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve is greater than or equal to the predetermined difference threshold.

8. The surface dust removal control system for powder pressing and molding according to claim 7, characterized in that, The dust removal process correction module determines that the condition for increasing the number of pulses is that the airflow pressure field stability of the dust removal pulse jet device meets the standard.

9. The surface dust removal control system for powder pressing and molding according to claim 8, characterized in that, The condition for the dust removal process correction module to determine the adjustment range of the nozzle outlet flow distribution is that the airflow pressure field stability of the dust removal pulse jet device does not meet the standard.

10. The surface dust removal control system for powder pressing and molding according to claim 9, characterized in that, The dust removal process correction module determines the adjustment range of the nozzle outlet flow distribution based on the difference between the characteristic value of the dust removal pulse valve and the predetermined characteristic threshold of the dust removal pulse valve.

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