Vibrating screening assembly, vibrating screening device and method of controlling vibrating screening

Abstract

This invention provides a vibrating screening component, a vibrating screening device, and a control method for vibrating screening. The vibrating screening component includes: a device frame, a pressure spring, a screening chamber, a vibration component, and an air blowing component. The first end of the pressure spring is connected to the device frame. The screening chamber includes a top cover, a lower base, and a diversion screen, which is located between the top cover and the lower base and connected to the second end of the pressure spring. The vibration component includes a pneumatic vibrator for driving the diversion screen to vibrate. The air blowing component includes a back-blowing nozzle facing the diversion screen. According to the vibrating screening component of this application, the vibration of the vibration component and the back-blowing of the air blowing component combine to form a synergistic anti-clogging mechanism. Even if a blockage occurs, it can be cleared online and quickly without stopping the machine, thus ensuring long-term stable and efficient screening operations.

Description

Technical Field

[0001] This invention relates to the field of additive screening technology, and in particular to a vibrating screening component, a vibrating screening device, and a vibrating screening control method. Background Technology

[0002] Laser selective melting (LSM) is based on the principle of layer-by-layer scanning and deposition, and features high precision and the ability to create complex structures. After forming, the metal powder used needs to be collected and sieved to remove large particles or impurities, thus enabling powder recycling. Without sieving, these large particles and impurities would significantly affect the quality of subsequent products.

[0003] As additive manufacturing products become larger, the amount of powder required increases dramatically, placing higher demands on the efficiency and continuity of powder screening. While existing powder screening machines have reduced the workload of operators to some extent, they generally suffer from screen clogging, requiring frequent shutdowns for manual cleaning, which disrupts production.

[0004] Therefore, there is an urgent need in this field for a new screening solution that can achieve high efficiency, continuous operation, safety and automation, in order to solve the shortcomings of existing technologies such as low screening efficiency, easy clogging and the need for manual intervention. Summary of the Invention

[0005] This invention provides a vibrating screening component, a vibrating screening device, and a corresponding control method. Through the anti-clogging mechanism of the combined action of vibration and air blowing, it solves the problems of low screening efficiency and easy clogging in existing vibrating screening equipment.

[0006] A vibrating screening assembly according to this application includes: Equipment frame; A pressure spring, the first end of which is connected to the device frame; The powder screening chamber includes an upper cover, a lower base, and a diversion screen. The diversion screen is located between the upper cover and the lower base, and is connected to the second end of the pressure spring. A vibration assembly, comprising a pneumatic vibrator for driving the vibration of a diversion screen; An air blowing assembly, the air blowing assembly including a back-blowing nozzle, the back-blowing nozzle being installed at least one of the lower base of the powder screening chamber and the upper top cover of the powder screening chamber, and facing the diversion screen.

[0007] According to the vibrating screening component of this application, the vibration of the vibrating component and the back-blowing of the air blowing component combine to form a synergistic anti-clogging mechanism. Even if a blockage occurs, it can be cleared online and quickly without stopping the machine, thereby ensuring long-term stable and efficient screening operations. The screening efficiency is significantly improved compared with traditional equipment.

[0008] According to a vibrating screening assembly provided by the present invention, the number of pneumatic vibrators is at least three, and the pneumatic vibrators are evenly distributed on the side of the diversion screen.

[0009] According to one embodiment of the present invention, each of the pneumatic vibrators is provided with a corresponding pressure regulating valve, and the input air pressure of each pressure regulating valve is adjustable.

[0010] According to one embodiment of the present invention, a controller is included, which is used to control the opening and closing of pneumatic vibrators at different positions, and to control the input air pressure of different pressure regulating valves.

[0011] According to one embodiment of the present invention, the side of the diversion screen is provided with a connector, which is connected to the second end of the pressure spring.

[0012] According to one embodiment of the present invention, the diversion screen is supported by the pressure spring and forms an inclined angle of 15° relative to the horizontal plane, so that the powder slides down the screen surface under vibration.

[0013] A control method for vibrating screens according to the present invention, applied to the above-mentioned vibrating screen assembly, is characterized by comprising the following steps: The vibration assembly is activated to vibrate the diversion screen to sieve the powder; According to preset conditions, the air blowing component is controlled to blow air onto the screen.

[0014] According to an embodiment of the present invention, activating the vibration assembly to vibrate the diversion screen for sieving the powder includes: The vibration force of at least one of the pneumatic vibrators is adjusted according to the powder collection speed.

[0015] According to an embodiment of the present invention, controlling the air blowing assembly to blow air onto the screen according to preset conditions includes: When inert gas protection is required for the screen, gas washing control is performed, causing the blowing device to blow inert gas onto the screen at a first pressure and flow rate. When it is necessary to clean the clogged screen, backflush control is executed, causing the blowing device to blow gas onto the screen at a second pressure and flow rate, wherein the second pressure is greater than the first pressure.

[0016] An additive screening apparatus according to the present invention includes: The vibrating screening assembly described above.

[0017] This invention combines high-frequency vibration of the vibrating component with pulsed backflushing of the air blowing component to form a synergistic and efficient anti-clogging mechanism. Even if the screen becomes clogged, it can be cleared online and quickly without downtime for maintenance. This not only ensures stable and efficient screening operations over a long period of time, but also greatly improves the safety of handling active metal powders through its sealed design and inert gas protection function, reducing health hazards to operators and environmental pollution. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is one of the structural schematic diagrams of the vibrating screening device provided by the present invention.

[0020] Figure 2 This is the second structural schematic diagram of the vibrating screening device provided by the present invention.

[0021] Figure 3 yes Figure 1 A schematic diagram of the AA cross-sectional structure of the vibrating screening device provided in the embodiment.

[0022] Figure 4 This is the third structural schematic diagram of the vibrating screening device provided by the present invention.

[0023] Figure 5 yes Figure 4 A BB cross-sectional view of the vibrating screening device provided in the embodiment.

[0024] Figure 6 yes Figure 5 An enlarged structural diagram of point C of the vibrating screening device provided in the embodiment.

[0025] Figure 7 This is the fourth structural schematic diagram of the vibrating screening device provided by the present invention.

[0026] Figure 8 This is a schematic diagram of the steps of the vibrating screening method provided by the present invention.

[0027] Figure 9 This is a schematic diagram of the feeding process of the vibrating screening device provided by the present invention.

[0028] Figure 10 This is a schematic diagram of the powder screening process of the vibrating screening device provided by the present invention.

[0029] Figure 11 This is a schematic diagram of the manual backflushing and washing process of the vibrating screening device provided by the present invention.

[0030] Figure label: 1. Feeding system; A1. Feeding hopper top cover; A2. Feeding hopper; A3. First sealing clamp assembly; A4. First pneumatic butterfly valve; A5. First material level sensor; A6. Storage tank; 2. Material feeding control system; B1. Frequent start motor; B2. Motor bracket; B3. Coupling; B4. Inclined chute discharge roller; B5. Discharge bin housing; B6. Left end cover; B7. Sealed bearing; B8. Felt sealing ring; B9. End face sealing ring; B10. Right end cover; 3. Vibrating Screening System; C1. Top Cover of Screening Chamber; C2. Pneumatic Vibrator; C3. Pressure Spring; C4. Lower Base of Screening Chamber; C5. Equipment Frame; C6. Pressure Relief Connector; C7. Diverter Screen; C8. Conical Backflush Nozzle; C9. Protective Air Connector; C10. Large Particle Discharge Pipe; C11. Second Sealing Clamp Assembly; C12. Sealing Blind Plate; C13. Oxygen Content Sensor; C14. Screening Section; C15. Separation Section; C16. First Chamber; C17. Upper Chamber Space; C18. Large Particle Recovery Chamber; C19. Second Chamber; C20. Baffle; C21. Qualified Powder Recovery Chamber; C22. Large Particle Recovery Chamber; C23. Connecting Parts; 4. Material collection system; D1, second pneumatic butterfly valve; D2, third sealing clamp assembly; D3, bellows; D4, material collection bucket; D5, second material level sensor. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0032] A vibrating screening assembly, as described above Figures 1 to 7The vibrating screening assembly includes: a frame C5, a pressure spring C3, a screening chamber, a vibration assembly, and an air blowing assembly. The first end of the pressure spring C3 is connected to the frame C5; the screening chamber includes an upper cover C1, a lower base C4, and a diversion screen C7, which is located between the upper cover C1 and the lower base C4, and is connected to the second end of the pressure spring C3; the vibration assembly includes a pneumatic vibrator C2, which drives the diversion screen C7 to vibrate; the air blowing assembly includes a back-blowing nozzle C8, which is installed at least one of the lower base C4 and the upper cover C1, and faces the diversion screen C7.

[0033] The equipment frame C5 serves as the basic support structure for the entire assembly, providing a mounting base for other components. It can be welded or assembled from rigid materials such as structural steel or aluminum alloy, possessing sufficient strength and stability to withstand vibration.

[0034] Multiple pressure springs C3 are provided, preferably four symmetrically distributed around the central axis of the powder screening chamber. The first end of each pressure spring C3 is fixedly connected to the crossbeam or mounting plate above the equipment frame C5 by bolts or clips. The main function of the pressure springs C3 is to provide elastic support for the powder screening chamber, enabling it to generate slight vibration displacement in the vertical direction, while absorbing some vibration energy and reducing the impact on the equipment frame C5.

[0035] The powder screening chamber adopts a split structure, mainly including the top cover of the powder screening chamber C1, the bottom base of the powder screening chamber C4, and the diversion screen C7.

[0036] The top cover C1 of the sieving chamber is equipped with a feed port for receiving the metal powder to be sieved. The lower base C4 of the sieving chamber has outlets for qualified powder (not shown in the diagram) and coarse powder / impurity powder (not shown in the diagram). A diversion screen C7 is sandwiched between the top cover C1 and the lower base C4 of the sieving chamber, and is detachably and sealingly connected to both via flanges and fasteners such as bolts, facilitating the replacement and cleaning of screens with different mesh sizes. The mesh size of the diversion screen C7 is selected according to the particle size of the required qualified powder. The outer edge of the diversion screen C7 or a specific connection point is connected to the second end of the pressure spring C3 via a connector, thereby suspending the entire sieving chamber below the equipment frame C5.

[0037] A vibration assembly is used to drive the powder screening chamber, particularly to drive the diversion screen C7 to generate high-frequency micro-amplitude vibration. In this embodiment, the vibration assembly includes at least one pneumatic vibrator C2. The pneumatic vibrator C2 is fixed to the outer wall or top of the top cover C1 of the powder screening chamber by a mounting bracket. Its air inlet is connected to an external compressed air source through an air pipe. When compressed air drives the pneumatic vibrator C2 to work, the periodic excitation force generated is directly transmitted to the powder screening chamber, causing the diversion screen C7 to generate high-frequency vibration. This vibration can effectively break the bridging phenomenon of powder, allowing qualified fine powder to efficiently fall through the mesh into the qualified powder outlet of the base C4 under the powder screening chamber, while coarse powder or agglomerates flow along the screen surface to the coarse powder outlet.

[0038] An air-blowing assembly is used for gas protection or online backflushing cleaning of the distribution screen C7 to prevent fine powder from clogging the mesh. The air-blowing assembly includes at least one backflushing nozzle C8. The backflushing nozzle C8 is preferably a fan-shaped or conical nozzle to create an airflow with a wide coverage area. In a preferred embodiment, the backflushing nozzle C8 is mounted on the inner wall of the base C4 under the powder screening chamber, with its nozzle facing the lower surface of the distribution screen C7. This arrangement enables "bottom-up" backflushing, which most effectively blows out the powder clogging the mesh, resulting in a significant cleaning effect.

[0039] The air inlet of the backflush nozzle C8 is connected to an external air source via a pipeline and a solenoid valve. The operation of the air blowing assembly can be linked with the vibration assembly or controlled independently by the controller. For example, it can be set to an intermittent working mode: during the screening process, the pneumatic vibrator C2 works continuously, while the backflush nozzle C8 opens every certain period of time, such as 30 seconds, for 0.5 seconds, to perform pulse-like backflush, which effectively prevents clogging without excessively interfering with the normal screening flow field. The gas protection or backflush cleaning function is specifically manifested in the following ways: when the equipment is in standby or just starting to work, inert gases such as nitrogen or argon can be introduced to form a protective atmosphere to prevent powder oxidation; during the screening process, pulse-like backflush is used to clear mesh blockage and maintain screening efficiency.

[0040] In one embodiment, the backflush nozzle C8 is installed not only on the lower base C4 of the sieving chamber but also on the upper cover C1 of the sieving chamber. Specifically, the backflush nozzle C8 located on the lower base C4 faces the lower surface of the diversion screen C7, and is used to perform a powerful online backflush cleaning function. The backflush nozzle C8 located on the upper cover C1 faces the space above or the upper surface of the diversion screen C7, and its main function is to form a uniform gas protective curtain to prevent external oxygen from entering the chamber and may assist in breaking up powder clumps. This simultaneous upper and lower arrangement integrates the dual advantages of efficient online cleaning and reliable gas protection, and is particularly suitable for sieving highly oxygen-sensitive metal powders such as titanium alloys and aluminum alloys.

[0041] The working principle of this invention is briefly described as follows: The metal powder to be screened enters through the inlet C1 on the top cover of the screening chamber and falls onto the diversion screen C7. The pneumatic vibrator C2 operates, driving the screen to vibrate, allowing qualified fine powder to pass through the filter screen and fall into the qualified powder outlet, while coarse powder or impurities are guided to the coarse powder / impurity outlet. During this process, the air blowing assembly intermittently injects gas, such as compressed air or inert gas, into the screen according to a set program, clearing blockages from below and providing a protective atmosphere from above, thereby ensuring that the screening process is efficient, continuous, and safe.

[0042] According to the present invention, a vibrating screening assembly is provided, wherein the number of pneumatic vibrators C2 is at least three, and the pneumatic vibrators C2 are evenly distributed on the side of the diversion screen C7.

[0043] In this embodiment, the number of pneumatic vibrators C2 is set to at least three. Preferably, as follows: Figure 1 As shown, three pneumatic vibrators C2 are used, which are evenly arranged circumferentially on the sides of the diversion screen C7. More preferably, when the screening chamber is circular and large in size, four, six or more pneumatic vibrators C2 can be used, and their distribution should be ensured to be evenly and symmetrically distributed circumferentially along the diversion screen C7.

[0044] The pneumatic vibrator C2 is fixed to the side wall of the top cover C1 of the powder screening chamber by a special mounting bracket. The direction of its excitation force output shaft is configured to be at a specific angle to the plane of the diversion screen C7, such as perpendicular or with a certain inclination angle, to ensure that the vibration energy is efficiently transmitted to the entire screen surface.

[0045] According to one embodiment of the present invention, each pneumatic vibrator C2 is provided with a corresponding pressure regulating valve, and the input air pressure of each pressure regulating valve is adjustable.

[0046] Each pneumatic vibrator C2 has an independent pressure regulating valve on its air intake passage. The input air pressure of each pressure regulating valve can be adjusted independently according to actual process requirements. Precision pressure regulating valves can be selected, and electromagnetic switching valve functions can be integrated for automated control by a central controller.

[0047] By adjusting the input air pressure of a single pressure regulating valve, the vibration intensity of the corresponding individual pneumatic vibrator C2 can be independently and precisely adjusted. When the powder to be screened is unevenly distributed on the screen, for example, the powder is thicker directly below the feed inlet and thinner at the edges, a differentiated vibration strategy can be implemented. For areas with thicker powder layers, the air pressure of the corresponding pneumatic vibrator C2 can be appropriately increased to enhance its vibration intensity and improve its penetration and screening capabilities; for areas with thinner powder layers, the air pressure can be appropriately reduced to prevent the powder from splashing or breaking due to excessive vibration.

[0048] By asymmetrically setting the intensity of vibrators at different positions, the flow direction and speed of powder on the screen can be actively controlled. For example, by increasing the intensity of the vibrator pointing towards the coarse powder outlet, a stronger directional vibration wave can be generated, thereby accelerating the pushing of coarse powder or agglomerates towards and out of the coarse powder outlet, effectively preventing blockage near the outlet and improving processing efficiency.

[0049] The optimal screening vibration intensity may vary depending on the type of metal powder, such as stainless steel, titanium alloy, or different particle sizes or viscosities. This embodiment allows operators to quickly change the overall or local vibration intensity by adjusting the air pressure, enabling a single device to process multiple materials with optimal parameters, greatly enhancing the equipment's versatility and process adaptability.

[0050] According to one embodiment of the present invention, a controller is included, which is used to control the opening and closing of pneumatic vibrators C2 at different positions, and to control the input air pressure of different pressure regulating valves.

[0051] The vibrating screen assembly also includes a controller (not shown in the figure). The controller is electrically connected to the on / off solenoid valves of each pneumatic vibrator C2 and the pressure regulating valve corresponding to each pneumatic vibrator C2 via circuits and pneumatic control loops.

[0052] During the screening process, uneven feeding or material characteristics may cause powder to accumulate thickly on a certain side or in a local area of ​​the diversion screen C7, resulting in the risk of clogging or a decrease in screening efficiency.

[0053] When this situation occurs, it can be detected by visual sensors, screen load sensors, or manually triggered by the operator based on experience, and the controller can respond immediately. For example, when a large amount of powder is detected on the right side, the controller can execute the following commands: if the right-side vibrator is off, it will be turned on immediately; if it is already on, its vibration intensity will be significantly increased by increasing the air pressure of its regulating valve. The enhanced right-side vibrator generates stronger vibration force, specifically targeting the powder accumulation area. This targeted, powerful vibration can quickly break up clumps, promote powder fluidization, and accelerate the conveying and screening of materials in this area. When the sensor detects that the powder accumulation has subsided, or after a preset time, the controller automatically adjusts the air pressure of the vibrator back to normal, restoring the entire screen to a balanced vibration state.

[0054] According to one embodiment of the present invention, the side of the diversion screen C7 is provided with a connector, which is connected to the second end of the pressure spring C3.

[0055] Specifically, the connectors can be lugs, mounting plates, or connecting flanges that are welded or installed on the side wall of the screen using fasteners.

[0056] To avoid stress concentration and low vibration energy transfer efficiency caused by rigid connections, the connector can be connected to the second end of the pressure spring C3 via a universal joint or spherical joint. This flexible connection design allows the screening chamber to oscillate slightly in multiple directions during vibration without generating excessive bending stress on the spring or connection point, ensuring smooth vibration transmission and extending equipment lifespan.

[0057] The number of connecting parts corresponds to the number of pressure springs C3, and they are evenly and symmetrically distributed around the axis of the diversion screen C7. For example, when four pressure springs C3 are used, the corresponding four connecting parts are also evenly arranged at 90-degree intervals. This symmetrical layout ensures that the screening chamber is uniformly elastically supported, allowing it to maintain a stable posture during vibration and preventing tilting or twisting, thereby ensuring the uniformity of screening.

[0058] According to one embodiment of the present invention, the diversion screen C7 is supported by the pressure spring C3 and forms an inclined angle of 15° relative to the horizontal plane, so that the powder slides down the screen surface under vibration.

[0059] Understandably, the 15° inclination angle provides a clear gravitational component for the movement of powder on the sieve surface. Under the vibration generated by the pneumatic vibrator C2, the powder not only jumps and disperses to promote sieve passage, but also slides continuously and stably along the inclined surface of the sieve to the lower side under the action of the tangential component of gravity. This synergistic effect of "vibration" and "gravitational sliding" achieves the ideal effect of "jumping and sieving while being conveyed forward" during the sieving process.

[0060] This tilt angle ensures a reasonable flow path and residence time for the powder from the higher side of the feed point to the lower side of the coarse powder discharge point. If the angle is too small (<5°), the powder flow is slow, which can easily lead to an excessively thick powder layer on the screen surface, reducing screening efficiency and even causing blockage. If the angle is too large (>25°), the powder flow rate is too fast, the residence time is too short, and fine powder is carried away before it can pass through the screen, resulting in incomplete screening and a decrease in recovery rate. A 15° tilt angle has been proven in practice to ensure sufficient screening while achieving efficient and smooth slag discharge.

[0061] The inclined design allows the powder layer to flow dynamically on the screen surface, rather than being statically accumulated. This creates more favorable conditions for the cleaning effect of the backflushing nozzle C8. The pulsed airflow can more easily penetrate the flowing powder layer and blow away blockages. These blown-away impurities are discharged downwards along with the powder flow, achieving dynamic online cleaning.

[0062] In one embodiment, the air blowing assembly is used for inert gas protection or online backflushing cleaning of the distribution screen C7. The air blowing assembly includes at least one conical backflushing nozzle C8 mounted on the back of the base C4 under the powder screening chamber, with its nozzle facing the lower surface of the distribution screen C7. Preferably, a row of, for example, five sets of conical backflushing nozzles C8 is provided, with an air delivery angle of not less than 60°, capable of generating a high-speed airflow of not less than 700 L / min under a protective gas pressure of 0.5-0.7 Bar, achieving "bottom-up" pulsed backflushing and efficiently cleaning the powder clogging the mesh.

[0063] The air inlet pipe of the air blowing assembly is connected to the protective air connector C9, and the two working modes are switched through a three-position five-way closed solenoid valve: air washing control and backflush control.

[0064] In the gas scrubbing control mode, during the initial startup of the equipment or when processing oxygen-sensitive reactive powders, the controller can cause the blowing device to continuously or intermittently blow inert gas, such as nitrogen or argon, onto the screen at a low initial pressure P1 and flow rate Q1 to replace the air in the chamber and create a protective atmosphere. For example, P1 can be set at 0.1-0.3 MPa to maintain a slight positive pressure inside the chamber.

[0065] In backflushing control mode, the controller can activate the blowing device at regular intervals during the screening process, such as every 0.5 seconds every 30 seconds, or trigger it according to the blockage situation. The controller causes the blowing device to pulse-blow gas (compressed air or inert gas) to the screen at a second pressure P2 and flow rate Q2 that is significantly higher than the first pressure, generating a high-speed, high-impact airflow to blow out the blockage. For example, P2 can be set to 0.5-0.8 MPa.

[0066] In addition, the powder screening chamber is equipped with a pressure relief connector C6 for venting internal gas and an oxygen content sensor C13 for real-time monitoring of the oxygen concentration inside the chamber. The monitoring results can serve as the basis for the controller to perform gas washing control.

[0067] According to the present invention, a control method for vibrating screening, applied to the above-mentioned vibrating screening assembly, includes the following steps: Start the vibration assembly to vibrate the diversion screen C7 to sieve the powder; According to preset conditions, the air blowing component is controlled to blow air onto the screen.

[0068] The controller activates the vibration assembly by turning on one or more pneumatic vibrators C2, causing the diversion screen C7 to vibrate. Powder falls into the sieving chamber through the inlet of the top cover C1 and is sieved on the vibrating diversion screen C7. At this time, the air blowing assembly can be set to standby or operate in basic mode.

[0069] The feedback-based intelligent control cycle control of the air blowing component to blow air onto the screen includes a vibration adaptive adjustment strategy based on powder collection speed, an air blowing component control strategy based on preset program, and a vibration local enhancement strategy based on local blockage identification.

[0070] According to one embodiment of the present invention, activating the vibration assembly to vibrate the diversion screen C7 for sieving powder includes: The vibration force of at least one of the pneumatic vibrators C2 is adjusted according to the powder collection speed.

[0071] The powder collection rate is defined as the amount of powder collected per unit time at the qualified powder outlet, for example, in kilograms per minute. This parameter can be monitored in real time by placing a weight sensor, such as a weighing module or a flow meter, below the qualified powder outlet.

[0072] Vibration adaptive regulation strategies based on powder collection velocity include: The controller compares the real-time monitored powder collection speed with the preset speed threshold, i.e., the preset speed value.

[0073] When the powder collection speed remains below the preset value, it indicates that the sieving efficiency is unsatisfactory, possibly due to powder moisture, changes in particle size distribution, or initial clogging of the screen. In this case, the controller executes an adjustment command: increasing the vibration force of at least one pneumatic vibrator C2. For example, the controller can send a command to the pressure regulating valve responsible for this vibrator, increasing its air pressure from the default 0.2 MPa (approximately 2 bar) to 0.4 MPa (approximately 4 bar). This increase in force helps to enhance vibration intensity, break up clumps, and promote the passage of fine powder through the screen.

[0074] When the powder collection speed is higher than the preset speed value and the equipment is running smoothly, the controller can maintain the current parameters or adjust the vibration intensity back to the energy-saving level.

[0075] The air blowing component control strategy based on the preset program includes: The controller controls the operation of the backflush nozzle C8 of the air blowing assembly according to a preset program. In one embodiment, it includes: Timed backflushing mode: Regardless of the screening status, the controller opens the backflushing nozzle C8 once every 30 seconds for 0.5 seconds at fixed time intervals for preventive cleaning.

[0076] Linked backflush mode: The "preset condition" can be that the vibrator is turned on. For example, after the vibration component is started, air blowing begins a few seconds later, or when the vibration intensity increases, the air blowing time is simultaneously enhanced or extended to form a synergy between vibration and backflush.

[0077] Manual Pulse Mode: Operators can manually trigger a powerful backflush from the control interface to handle sudden blockages.

[0078] The vibration local enhancement strategy based on local blockage identification includes identifying whether abnormal powder accumulation occurs at specific locations, such as a side, on the diversion screen C7 by using visual sensors installed on the side wall of the screen chamber or sensors that monitor vibration loads in different areas.

[0079] When localized accumulation is detected, the controller does not simply increase the intensity of all vibrators, but selectively strengthens the vibration force of the pneumatic vibrator C2 pointing towards the blocked area, and can even briefly shut down the vibrator on the opposite side to form a strong vibration wave pointing towards the slag discharge port, so as to achieve precise and efficient unblocking and avoid energy waste.

[0080] After the screening task is completed, the controller stops the vibration and blowing components. Before the next startup, the air pressure parameters of all pneumatic vibrators C2 can be reset to their initial default values.

[0081] According to an embodiment of the present invention, controlling the air blowing assembly to blow air onto the screen according to preset conditions includes: When inert gas protection is required for the screen, gas washing control is executed, so that the blowing device blows inert gas to the screen at a first pressure and flow rate. When it is necessary to clean the clogged screen, backflush control is executed, causing the air blowing device to blow gas onto the screen at a second pressure and flow rate, wherein the second pressure is greater than the first pressure.

[0082] The operating mode of the air blowing component is automatically determined by the controller based on process requirements or switched upon receiving external commands such as operator input. It is triggered when inert gas protection of the screening chamber is required. This can occur during initial equipment startup, when screening flammable and explosive metal powders such as titanium alloys and aluminum alloys, or when screening highly oxygen-sensitive reactive metal powders. Its fundamental purpose is to replace the air inside the chamber, creating a low-oxygen or oxygen-free environment to prevent oxidation or explosion of the powder during the screening process.

[0083] The controller executes the gas washing control program. In this mode, the controller controls the backflush nozzle C8 to blow inert gas, such as nitrogen or argon, into the screen and screening chamber at a first pressure P1 and a first flow rate Q1.

[0084] The initial pressure P1 is relatively low, and the initial flow rate Q1 is relatively small and can be continuous or intermittent. The goal is not to forcefully impact the screen, but rather to create a stable, uniform gas protective curtain covering the entire screen area and gradually displace the air inside the chamber. For example, P1 can be set at 0.1-0.3 MPa to maintain a slight positive pressure inside the chamber, effectively isolating it from external air.

[0085] This mode can be run separately for a period of time, such as 2-5 minutes, before screening begins to ensure the washing effect and maintain the background level gas supply throughout the screening process.

[0086] Triggered when clogging of the screen needs to be cleared. This can be based on timed, preventative cleaning cycles, feedback based on decreased screening efficiency, or emergency cleaning initiated manually by the operator.

[0087] The controller executes the backflush control program. In this mode, the controller controls the backflush nozzle C8 to blow gas onto the screen at a second pressure P2 and a second flow rate Q2. The gas can be compressed air, if it is not sensitive to oxygen; or an inert gas can continue to be used.

[0088] The second pressure P2 is significantly greater than the first pressure P1, i.e., P2 >> P1, and the second flow rate Q2 is also correspondingly larger. The goal is to generate a high-speed, high-impact airflow that acts directly on the back of the screen, blowing out the powder particles clogging the mesh. This mode can use a short pulse, such as an on-time of 0.2-1.0 seconds, to avoid excessive interference with the sieving flow field. For example, P2 can be set to 0.5-0.8 MPa.

[0089] This mode operates intermittently during the screening process, working in conjunction with vibrating screening.

[0090] This embodiment also provides a control method for vibrating screens, which is applied to the aforementioned vibrating screen assembly and executed by a controller such as a PLC or industrial computer. The method includes the following steps: Step 1: Start vibration. The controller starts one or more pneumatic vibrators C2, causing the diversion screen C7 to vibrate.

[0091] Step Two: Intelligent Vibration Adjustment. The controller monitors the powder collection speed in real time via a weight sensor or flow meter located at the qualified powder outlet. When the collection speed consistently falls below a preset threshold, indicating a decrease in sieving efficiency, the controller will automatically increase the air pressure of at least one pneumatic vibrator C2 to increase the vibration force, break up powder clumps, and promote sieving. When the collection speed returns to normal, the controller can adjust the vibration intensity back to normal or energy-saving levels.

[0092] Step 3: Perform air blowing. The controller controls the air blowing assembly to blow air onto the screen according to preset conditions.

[0093] Preset conditions can be: 1. Timed backflushing: Regardless of the screening status, pulse backflushing is performed at fixed time intervals for preventative cleaning.

[0094] 2. Synchronized backflushing: Backflushing is performed synchronously after the vibrator is started or when the vibration intensity increases, forming a synergistic effect between vibration and backflushing.

[0095] 3. Gas scrubbing protection: During initial startup or when sieving active powder, gas scrubbing control is performed based on the reading of oxygen content sensor C13 until the oxygen content is below a safe threshold, such as 2%.

[0096] 4. Manual Trigger: Operators can manually trigger the powerful backflushing or purging program through the control interface to handle sudden blockages or meet specific process requirements.

[0097] An additive screening device according to the present invention includes: the above-described vibrating screening assembly.

[0098] A vibrating screening assembly according to this application includes: The powder screening chamber is equipped with a diversion screen C7. The vibration assembly includes at least one pneumatic vibrator C2 mounted on the powder screening chamber, the pneumatic vibrator C2 being used to apply vibration to the powder screening chamber; The air blowing assembly is located inside the powder screening chamber and faces the diversion screen C7.

[0099] According to one embodiment of this application, the vibrating screening assembly includes a pressure spring C3, one end of which is connected to the screening chamber and the other end is connected to the equipment frame C5. The pressure spring C3 is used to support the screening chamber. When the pneumatic vibrator C2 applies vibration to the diversion screen C7, the screening chamber as a whole vibrates relative to the equipment frame C5.

[0100] The vibration assembly includes at least one pneumatic vibrator C2. The pneumatic vibrator C2 is fixedly installed on the outer wall of the screening chamber by means of bolts, flanges, or welding. Preferably, the pneumatic vibrator C2 is installed on the side wall or top of the screening chamber, ensuring that the excitation force it generates can be effectively transmitted to the diversion screen C7. The pneumatic vibrator C2 operates by receiving compressed air from an external air source (not shown in the diagram), generating high-frequency, small-amplitude mechanical vibration. This vibration is transmitted through the chamber wall to the internal diversion screen C7, causing the material on the screen to jump and slide, thereby preventing screen clogging and improving screening efficiency and accuracy.

[0101] The elastic support mechanism includes multiple pressure springs C3. One end of each pressure spring C3 is connected, for example, to a protruding support at the bottom or side wall of the screening chamber, and the other end is connected, for example, to a fixed equipment frame C5. The equipment frame C5 can be a rigid frame fixed to the ground or a work platform. The function of the pressure springs C3 is to elastically support the entire screening chamber and its internal components, keeping it in a "suspended" state. When the pneumatic vibrator C2 is working, with the cooperation of the pressure springs C3, the entire screening chamber can freely and efficiently vibrate at small amplitudes relative to the fixed equipment frame C5 without transmitting violent vibrations to the equipment frame C5 or the external environment. This not only amplifies the effective vibration effect of the screen but also plays a role in vibration isolation and noise reduction.

[0102] The material to be screened, such as powder, is added through the feed inlet of the screening chamber and falls onto the high end of the diverting screen C7. The pneumatic vibrator C2 and the air blowing assembly are then activated. Under the vibration of the pneumatic vibrator C2, the material jumps and moves towards the lower end of the inclined screen surface. Simultaneously, the air blowing assembly sprays airflow onto the material layer from above or the side. Qualified fine powder quickly passes through the screen holes under the combined action of vibration and airflow, becoming undersize material and exiting from the fine material outlet. Coarse particles that fail to pass through the screen holes continue to move along the screen surface to the coarse material outlet at the lower end, thus completing the material screening.

[0103] According to one embodiment of this application, the powder screening chamber includes an upper cover C1 and a lower base C4, a diversion screen C7 is disposed between the upper cover C1 and the lower base C4, and a pressure spring C3 is installed on the diversion screen C7.

[0104] The sieving chamber is the core working cavity of this vibrating screening assembly. From top to bottom, it includes a detachably connected upper cover C1 and a lower base C4. The upper cover C1 typically has a feed inlet, and the lower base C4 has a fine powder outlet. A diversion screen C7 is positioned between the upper cover C1 and the lower base C4, forming an independent screening space. This split structure facilitates the installation, cleaning, and replacement of the diversion screen C7.

[0105] Specifically, the upper ends of multiple pressure springs C3 are directly connected to the frame of the diversion screen C7 or a specific mounting point, while the lower ends of the pressure springs C3 are connected to a fixed equipment frame C5. The vibration assembly includes at least one pneumatic vibrator C2. The pneumatic vibrator C2 is preferably mounted directly on the frame of the diversion screen C7, or mounted on the lower base C4 of the screening chamber, which is rigidly connected to the diversion screen C7. In this way, the excitation force generated by the pneumatic vibrator C2 can be transmitted most directly and effectively to the core component requiring vibration—the diversion screen C7—without having to move the massive mass of the entire screening chamber, thus resulting in lower energy consumption and higher vibration efficiency.

[0106] In one embodiment, the base C4 of the powder screening chamber and the diversion screen C7 are rigidly connected by bolts or snap-fit ​​structures to form a unified vibrating body.

[0107] According to one embodiment of this application, at least one of the pressure springs C3 has a different length than the other pressure springs C3, the diversion screen C7 is inclined relative to the horizontal plane, and the pressure spring C3 with a lower relative position has a shorter length than the pressure spring C3 with a higher relative position.

[0108] Specifically, at least one of the pressure springs C3 has a different free length (i.e., its length under no-load condition) than the other pressure springs C3. By giving the pressure springs C3 at different positions different initial lengths, the supported diversion screen C7 can automatically form a certain angle relative to the horizontal plane after installation.

[0109] In one embodiment, the diversion screen C7 is configured to be higher at the front and lower at the rear. To achieve this, the pressure spring C3 located on the lower side of the front of the diversion screen C7 has a longer free length, while the pressure spring C3 located on the higher side of the rear has a shorter free length. When these springs of different lengths are installed in place, the system will naturally stabilize in a tilted state with a lower front and higher rear under the weight of the screen and the cabin.

[0110] According to one embodiment of this application, there are multiple pneumatic vibrators C2, with at least one pneumatic vibrator C2 located on different sides of the powder screening chamber.

[0111] In one embodiment, for an approximately rectangular screening chamber, two pneumatic vibrators C2 can be used. The first pneumatic vibrator C2 is installed on the left side wall of the base C4 under the screening chamber, and the second pneumatic vibrator C2 is symmetrically installed on its right side wall. This symmetrical arrangement allows the excitation force to be applied evenly to both sides of the screen frame, avoiding screen surface twisting that may be caused by unilateral excitation and ensuring the consistency of amplitude at all points on the screen surface.

[0112] In one embodiment, three or four pneumatic vibrators C2 can be used. For example, in addition to being installed on the left and right side walls, pneumatic vibrators C2 can also be installed at the front end of the feed end and / or the rear end of the discharge end of the screening chamber. This multi-point, multi-directional vibration excitation mode can generate complex composite vibration trajectories, more effectively breaking down material adhesion and clogging, and is particularly suitable for difficult-to-screen materials that are prone to adhesion and have high moisture content.

[0113] According to one embodiment of this application, the vibration assembly includes a pressure regulating valve for adjusting the vibration force of the pneumatic vibrator C2. A pressure regulating valve is connected in the air line between the compressed air source and the pneumatic vibrator C2. By adjusting the opening of this valve, the pressure of the compressed air entering the pneumatic vibrator C2 can be precisely controlled. The higher the air pressure, the greater the amplitude and impact force of the vibration generated by the pneumatic vibrator C2; conversely, the lower the pressure, the smaller the impact force.

[0114] Operators can flexibly adjust the vibration force according to the characteristics of the material to be screened, such as particle size, moisture content, and viscosity. For lightweight and fragile materials, a smaller vibration force can be used to prevent material breakage or dust dispersion; for moist and easily agglomerated materials, a larger vibration force can be used to ensure sufficient screening efficiency. This greatly enhances the equipment's process adaptability.

[0115] In one embodiment, the vibration assembly further includes a control switch for controlling the opening and closing of the pneumatic vibrator C2.

[0116] In a preferred embodiment, the control switch is a time relay. The time relay can be preset with a vibration cycle. For example, it can be set to a cycle mode of "vibrate for 30 seconds, stop for 10 seconds".

[0117] The pressure regulating valve and the time relay can be used individually or in combination. When used in combination, they can achieve complex and precise screening processes such as "vibrating at high amplitude for a period of time, then switching to low amplitude vibration, and then stopping," meeting the needs of high-end screening applications.

[0118] According to one embodiment of this application, both the vibration assembly and the pressure spring C3 are disposed on the side of the diversion screen C7.

[0119] A vibrating screening assembly according to this application includes: The powder screening chamber includes a lower base C4 and a diversion screen C7. The diversion screen C7 is installed above the lower base C4 of the powder screening chamber at a preset tilt angle relative to the horizontal plane. The diversion screen C7 is provided with at least one powder screening section C14 and at least one separation section C15; the base C4 of the powder screening chamber is provided with a qualified powder recovery chamber C21 and a large particle recovery chamber C22. Each powder screening section C14 is provided with a qualified powder recovery chamber C21 below it, and each separation section C15 is provided with a large particle recovery chamber C22 below it. A vibration assembly, connected to the diversion screen C7, is used to apply vibration to the diversion screen C7.

[0120] The sieving plane of the diversion screen C7 is provided with functional zones, including at least one sieving section C14 and at least one separation section C15. The sieving section C14 is the area on the diversion screen C7 with effective sieve holes. Its position corresponds one-to-one with the qualified powder recovery chamber C21 below. When powder is spread on the sieving section C14, under vibration, qualified powder with a particle size smaller than the sieve hole diameter can pass through the sieve holes and fall into the qualified powder recovery chamber C21 below. The separation section C15 is a through-hole or opening area on the diversion screen C7, with a size much larger than the sieve holes of the sieving section C14. Its purpose is to allow large particles or impurities to pass through unimpeded. The position of the separation section C15 corresponds one-to-one with the large particle recovery chamber C22 below. The separation section C15 can be a simple screenless area, or it can be equipped with an auxiliary grid with a larger aperture, serving only as a guide and preventing drop.

[0121] The arrangement of the sieving section C14 and the separation section C15 can be varied. In a preferred embodiment, the diversion screen C7 is rectangular. The sieving section C14 is located in the higher region of the rectangular screen in the inclined direction, while the separation section C15 is located in the lower region of the rectangular screen in the inclined direction. In this way, the powder falling from the feed inlet of the sieving chamber first reaches the higher sieving section C14 for primary sieving. Larger particles that are not sieved slide naturally along the inclined screen surface to the lower separation section C15 under the action of vibration and gravity, and finally fall into the large particle recovery chamber C22 through the separation section C15.

[0122] In one embodiment, the sieving section C14 and the separation section C15 on the diversion screen C7 are multiple alternating strip-shaped areas. For example, the entire screen surface can be divided into three strips: from the high end to the low end, the first sieving section C14, the separation section C15, and the second sieving section C14. The mixed powder first undergoes preliminary sieving through the first sieving section C14, with larger particles sliding to the middle separation section C15 and falling down. Some qualified powder entrained within the larger particles may be shaken off during the sliding process and have the opportunity to undergo secondary sieving in the subsequent second sieving section C14. This multi-stage sieving layout helps to further improve sieving efficiency and the recovery rate of qualified powder.

[0123] According to one embodiment of this application, when there is only one sieving section C14 and one separation section C15, the separation section C15 is located at the lower end of the sieving section C14.

[0124] According to one embodiment of this application, a baffle C20 is provided in the lower base C4 of the powder screening chamber. The baffle C20 is located below the edge of the separation section C15 of the diversion screen C7, separating the qualified powder recovery chamber C21 and the large particle recovery chamber C22.

[0125] Baffle C20 is vertically or nearly vertically positioned directly below the edge of the separation section C15 of the diversion screen C7. More specifically, the upper edge of baffle C20 should be as close as possible to the lower surface of the diversion screen C7, but with a small gap to avoid contact friction. The surface of baffle C20 is located between the qualified powder recovery chamber C21 of the powder screening section C14 and the large particle recovery chamber C22 of the separation section C15. It effectively prevents large particles of powder falling from the separation section C15 from splashing or rolling into the adjacent qualified powder recovery chamber C21 due to inertia or vibration; at the same time, it also prevents any trace dust that may be present in the qualified powder recovery chamber C21 from drifting into the large particle recovery chamber C22, thereby ensuring the purity of the collected powders and avoiding cross-contamination.

[0126] In one embodiment, the baffle C20 may be made of stainless steel, aluminum alloy, or engineering plastic.

[0127] According to one embodiment of this application, when there are multiple powder screening sections C14 and separation sections C15, the powder screening sections C14 and separation sections C15 are arranged at intervals.

[0128] Inside the base C4 of the powder sieving chamber, each powder sieving section C14 has a corresponding independent qualified powder recovery chamber C21 directly below it, and each separation section C15 has a corresponding large particle recovery chamber C22 directly below it. The mixed powder first falls onto the highest first powder sieving section C14 for initial sieving. Qualified powder falls into the first qualified powder recovery chamber C21. Large particles that are not sieved slide to the first separation section C15 and fall into the first large particle recovery chamber C22.

[0129] According to one embodiment of this application, the powder screening chamber includes a top cover C1, and the top cover C1 is provided with a feeding port, which is located above the end of the diversion screen C7 with a relatively higher height.

[0130] According to one embodiment of this application, the separation section C15 is constructed as a through slot, so that large particles of powder or impurities fall into the large particle recovery chamber C22 through the through slot.

[0131] A "through-slot" refers to a completely through opening or notch directly cut into the solid plate or mesh surface of the C7 diversion screen. This area is not covered by any screening media such as screens or grids, forming an open channel that allows materials to fall freely through.

[0132] The through-hole can be rectangular, circular, elliptical, or other regular or irregular geometric shapes. As a non-limiting example, the width of the through-hole can be designed to be 1.5 to 1.5 times the aperture of the C14 sieve in the powder screening section, thereby completely eliminating the risk of material jamming.

[0133] According to one embodiment of this application, the top cover of the powder chamber has a viewing window above the diversion screen C7.

[0134] According to one embodiment of this application, the tilt angle of the diversion screen C7 relative to the horizontal plane is adjustable.

[0135] The methods to achieve adjustable tilt angle include, but are not limited to, the following two: The entire sieving chamber can be installed at an adjustable angle. Specifically, an angle adjustment mechanism can be installed on the support frame or external base of the sieving chamber. When the angle needs to be changed, the entire sieving chamber (including the internal fixed screen) is rotated around the axis to the desired angle and then locked again. This method is simple and reliable, and the relative position of the screen and the chamber remains unchanged during adjustment.

[0136] The tilt angle of the diversion screen C7 can also be independently adjusted inside the screening chamber. One specific implementation involves connecting the higher end of the diversion screen C7 to the side wall of the screening chamber via a pivot or hinge structure, allowing it to rotate around this connection point. Simultaneously, a liftable support (e.g., a screw-driven lifting rod or a lockable hydraulic strut) is installed below or to the side of the lower end of the diversion screen C7. By adjusting the height of this support, the position of the lower end of the diversion screen C7 can be changed, thereby continuously and precisely altering the tilt angle of the entire screen plane. This method does not require altering the main body of the equipment, making adjustment more flexible and convenient.

[0137] According to one embodiment of this application, an external adjustment mechanism is included. The external adjustment mechanism is used to adjust the tilt angle of the entire powder screening chamber relative to the horizontal plane. The adjustment mechanism includes a pressure spring C3 and a connector C23. The pressure spring C3 is located outside the powder screening chamber, and the first end of the pressure spring C3 is connected to the equipment frame C5. The connector C23 is located on the side of the diversion screen C7. The connector C23 is used to connect the second end of the pressure spring C3. The connector C23 is configured to rotate and lock at a preset angle to adjust the overall tilt angle of the powder screening chamber.

[0138] Specifically, the pressure spring C3 is located on the outside of the powder screening chamber. Its first end is connected to the fixed equipment frame C5. The connector C23 is fixedly installed on the side of the powder screening chamber, which is rigidly connected to the diversion screen C7. The second end of the pressure spring C3 is connected to this connector C23.

[0139] Connector C23 is specially configured to rotate around its connection point with the side of the sieving chamber and reliably lock at a preset angle when the desired position is reached. When angle adjustment is required, the operator unlocks connector C23, rotates it to the new angle position, and then locks it again. This operation pulls or releases pressure spring C3, thereby changing the force and lever arm of the spring on the side of the sieving chamber, driving the entire sieving chamber to rotate around its fulcrum at the other end, achieving stepless or stepped adjustment of the overall tilt angle of the sieving chamber. Pressure spring C3 not only provides the adjusting force during this process but also acts as a buffer and provides stable support.

[0140] Suppose it is necessary to increase the tilt angle of the screening chamber. The operator unlocks connector C23, rotates it an angle in the direction that reduces the spring tension, and then locks it. At this time, the tension or supporting force of the spring on the screening chamber changes, and the entire chamber rotates to a larger tilt angle under the new balance of gravity and spring force. During the adjustment process, the relative positions of the diversion screen C7, the top cover C1 of the screening chamber, and the lower base remain unchanged, ensuring the integrity of the internal seal.

[0141] All adjusting components (springs, connector C23, locking device) are located outside the screening chamber, allowing the operator to adjust the tilt angle without opening or touching the internal sealed screening chamber.

[0142] According to one embodiment of this application, an internal adjustment mechanism is included. The internal adjustment mechanism is used to adjust the tilt angle of the diversion screen C7 relative to the horizontal plane. The diversion screen C7 is connected to the powder screening chamber through the internal adjustment mechanism. The internal adjustment mechanism includes a rotating component and a lifting component. One end of the diversion screen C7 is provided with one of the rotating component and the lifting component, and the other end of the diversion screen C7 is provided with the other of the rotating component and the lifting component.

[0143] The internal adjustment mechanism is used to independently adjust the tilt angle of the diversion screen C7 relative to the horizontal plane without changing the overall posture of the powder screening chamber. The diversion screen C7 is connected to and supported on the inner wall of the powder screening chamber through this internal adjustment mechanism.

[0144] In terms of specific connection method, the two ends of the diversion screen C7 along its inclined direction are connected separately, one end is connected to the rotating part, and the other end is connected to the lifting part.

[0145] The rotating component can be a hinge, a shaft, or a bearing housing, etc. Its core function is to allow the connecting end of the diversion screen C7 to rotate freely around a fixed axis, thereby providing angular freedom during adjustment and ensuring smooth changes in screen angle.

[0146] The lifting component can be a linear drive device such as a screw lifting mechanism, electric push rod, hydraulic cylinder, or telescopic rod with locking function. Its core function is to actively or passively change its own length, thereby raising or lowering the height of the connecting end of the diversion screen C7.

[0147] When the screen tilt angle needs to be adjusted, operate the lifting mechanism to extend or shorten it. For example, to increase the tilt angle, drive the lifting mechanism to shorten, lowering the height of the lower end of the diversion screen C7. At this time, the lower end of the screen descends under the action of the lifting mechanism, while the upper end swings down naturally around the axis of the rotating component.

[0148] A vibrating screening assembly according to this application includes: The powder screening chamber includes a diversion screen C7, which is inclined relative to the horizontal plane. The material falling on the diversion screen C7 can slide along the surface of the diversion screen C7, and the powder that meets the preset particle size requirements passes through the diversion screen C7. The blowing assembly includes a gas path control mechanism and at least one backflush nozzle. The gas path control mechanism is configured to supply at least two different pressures of gas to the backflush nozzle, which sprays gas toward the diversion screen C7.

[0149] According to one embodiment of this application, the gas path control mechanism includes: Protective air connector C9 is installed on the powder screening chamber and connected to the backflushing nozzle; The three-position five-way solenoid valve has an air inlet, a first output port, and a second output port; a pressure reducing valve is connected in series at the first output port to output gas at a first pressure; a pressure boosting valve is connected in series at the second output port to output gas at a second pressure; the pipelines of the first output port and the second output port are connected to the protective gas connector C9 after they are joined.

[0150] Understandably, the protective air connector C9 is fixedly installed on the wall of the powder screening chamber, serving as the connection interface between the external air path and the internal backflush nozzle, and is connected to the backflush nozzle through the internal pipeline.

[0151] The first output port is connected to a pressure reducing valve, which is used to regulate and stabilize the intake pressure at a preset first pressure. This pressure is usually set to a low value to maintain an inert protective atmosphere.

[0152] The second output port is connected to a booster valve, which is used to increase the intake pressure to a preset second pressure. This pressure is set to a higher value, suitable for periodic, powerful pulse backflushing to clear stubborn blockages.

[0153] According to one embodiment of this application, an oxygen content sensor C13 is included, which is installed on the powder screening chamber for detecting the oxygen content in the chamber; the gas path control mechanism includes a controller, which is electrically connected to the oxygen content sensor C13 and a three-position five-way solenoid valve respectively.

[0154] The controller is electrically connected to both the oxygen content sensor C13 and the three-position five-way solenoid valve. The controller receives the real-time signal from the oxygen content sensor C13 and outputs control commands accordingly to drive the three-position five-way solenoid valve to switch its operating state.

[0155] When the oxygen content data received by the controller is lower than the preset safety threshold, it determines that there is a risk of dust cloud combustion and explosion. The controller immediately issues a control command to switch the three-position five-way solenoid valve to the second operating position. At this time, the main gas line is cut off, and the backup inert gas line is connected to the backflushing nozzle. The system automatically switches to injecting inert gases such as nitrogen into the dust screening chamber.

[0156] According to one embodiment of this application, the powder screening chamber includes an upper cover C1, a lower base C4, and a diversion screen C7. The diversion screen C7 is disposed between the upper cover C1 and the lower base C4. Multiple sets of back-blowing nozzles are provided, which are arranged along the height direction of the lower base C4 to cover the diversion screen C7. The air outlet direction of the back-blowing nozzles forms an angle of more than 60° with the surface of the diversion screen C7.

[0157] To achieve thorough cleaning of the entire diversion screen C7 without any blind spots, multiple sets of backflushing nozzles are installed. These nozzles are arranged linearly or in a matrix along the height of the base C4 under the screening chamber. This layout ensures that the entire inclined surface of the diversion screen C7 is effectively covered by the airflow.

[0158] The installation angle of each set of backflush nozzles is precisely designed so that the air outlet direction forms an angle of more than 60° with the lower surface of the diversion screen C7 (i.e. the side facing away from the material). The larger angle ensures that the jet airflow has the maximum normal force, thereby obtaining the strongest ability to penetrate the screen holes and disturb the attached materials, resulting in the highest cleaning efficiency.

[0159] According to one embodiment of this application, it includes: Baffle C20 is vertically installed in the lower base C4 of the powder screening chamber, dividing the internal space of the lower base C4 into a qualified powder recovery chamber C21 and a large particle recovery chamber C22. The diversion screen C7 is provided with a powder screening section C14 and a separation section C15. The qualified powder recovery chamber C21 is located below the powder screening section C14, and the large particle recovery chamber C22 is located below the separation section C15. The bottom of the large particle recovery chamber C22 is connected to a large particle discharge pipe C10, and the end of the large particle discharge pipe C10 is equipped with a sealing clamp assembly and a sealing blind plate C12.

[0160] According to one embodiment of this application, there are multiple sets of backflushing nozzles, which are arranged along the height direction of the base C4 under the sieve chamber to cover the diversion screen C7.

[0161] This multi-layered vertical arrangement aims to ensure that the airflow ejected from different heights can fully and effectively cover the entire area of ​​the diversion screen C7. In particular, for inclined screens with larger areas or longer vertical projections, it can eliminate cleaning blind spots and achieve uniform cleaning from the near end to the far end.

[0162] According to one embodiment of this application, the air blowing assembly includes an angle adjustment structure. The back-blowing nozzle is mounted on the lower base C4 of the powder screening chamber through the angle adjustment structure. By adjusting the angle adjustment structure, the spray angle of the back-blowing nozzle relative to the diversion screen C7 can be changed.

[0163] This angle adjustment mechanism allows for fine-tuning of the orientation of the backflush nozzle. By adjusting this mechanism, the spray angle of the backflush nozzle relative to the back of the upper diversion screen C7 can be precisely changed, for example, adjusting the airflow from a vertical impact to an oblique impact at a certain acute angle to the screen.

[0164] Furthermore, as mentioned above, the backflush nozzles can be in multiple sets and arranged along the height direction of the base C4 under the sieving chamber to ensure coverage of the entire screen area. Preferably, each set or each backflush nozzle can be independently equipped with an angle adjustment structure, thereby allowing independent optimization of the spray angle for different areas.

[0165] Thanks to the angle adjustment structure, operators can adjust the airflow to the optimal impact angle based on the material's characteristics (such as viscosity and particle size) and the actual screening conditions. For example, for highly viscous materials, a smaller impact angle (closer to the tangential direction of the screen) can be used to generate stronger shearing force to scrape away the attached material; for conventional materials, a larger impact angle (closer to vertical) can be used to generate a direct thrust to remove stuck particles. This adjustability ensures efficient and energy-saving unclogging.

[0166] According to one embodiment of this application, the blowing assembly includes a pressure regulator for adjusting the gas pressure and flow rate delivered to the backflush nozzle.

[0167] This allows operators to dynamically adjust the blowing force during operation based on the characteristics of the material being processed (such as specific gravity, viscosity, and particle size) and the actual blockage situation, from gentle cleaning to powerful blowing, achieving precise control.

[0168] A vibrating screening assembly according to this application includes: The powder screening chamber includes a flow divider screen C7, which is provided with a powder screening section C14 and a separation section C15. The powder screening section C14 is used to allow powder that meets the preset particle size requirements to pass through, and the separation section C15 is used to allow powder that is larger than the preset particle size to pass through. Baffle C20 is connected to the diversion screen C7 and is located between the powder screening section C14 and the separation section C15; The diversion screen C7 and the baffle C20 divide the internal space of the powder screening chamber into a first cavity C16 and a second cavity C19. The first cavity C16 includes an upper cavity space C17 located above the diversion screen C7 and a large particle recovery cavity C18 located below the separation section C15. The second cavity C19 is located below the powder screening section C14.

[0169] Baffle C20 is vertically or inclinedly connected to the lower surface of the diversion screen C7, located at the junction of the powder screening section C14 and the separation section C15, and is used to prevent powder mixing.

[0170] During operation, the powder to be screened falls into the screening chamber from the feed inlet and lands on the diversion screen C7. Under vibration or gravity, fine powder falls through the screening section C14 into the lower second chamber C19 and is finally discharged from the fine powder outlet; larger particles move along the screen surface, pass through the separation section C15 and fall into the large particle recovery chamber C18, where they can be collected from the large particle discharge outlet on the side wall or bottom. The baffle C20 serves as a guide and separator to ensure a clear screening path.

[0171] Optionally, the diversion screen C7 can be designed as a detachable or adjustable structure to allow for the replacement of screens of different specifications to adapt to screening requirements for different particle sizes.

[0172] According to the vibrating screening assembly of this application, a diversion screen C7 integrating a powder screening section C14 and a separation section C15, guided by a baffle C20, simultaneously completes the screening of fine powder and the separation of large particles on the same screen surface. The compact structure reduces the equipment complexity of multi-stage screening in traditional processes. Large particles fall directly into the large particle recovery chamber C18 via the separation section C15, while fine powder falls into the second chamber C19 via the powder screening section C14, achieving synchronous discharge through dual channels. This eliminates the need to stop the machine to clean the material on the screen, making it suitable for continuous production.

[0173] According to one embodiment of this application, the diversion screen C7 forms an angle with the horizontal plane, so that the powder on the sieving section C14 can slide along the screen surface to the separation section C15; the separation section C15 is constructed as a through slot, so that large particles of powder or impurities fall from the upper cavity space C17 into the large particle recovery cavity C18 through the through slot.

[0174] The separation section C15 is specifically constructed as a through slot formed on the diversion screen C7. This through slot is located downstream of the sieving section C14, and its width and length can be designed according to the characteristics of the powder to be processed to ensure that large particles or agglomerated impurities can pass through smoothly. A baffle C20 is preferably located at the upstream edge of the through slot, perpendicular to the screen surface or at a certain angle, to prevent powder from accidentally falling before sliding into the through slot and to clearly separate the sieving areas.

[0175] The through-hole design allows large particles and impurities to be instantly and thoroughly discharged when they reach the end of the screen surface, avoiding the problems of them accumulating on the screen surface or needing to be cleaned in reverse. This ensures that the equipment can operate continuously and stably for a long time, making it particularly suitable for large-scale continuous production lines.

[0176] According to one embodiment of this application, the powder screening chamber includes an upper cover C1, a lower base C4, and a diversion screen C7. The diversion screen C7 is located between the upper cover C1 and the lower base C4. The lower base C4 is connected to a large particle discharge pipe C10, which is connected to a large particle recovery chamber C18. A sealing blind plate C12 is installed at the end of the large particle discharge pipe C10 through a sealing clamp assembly.

[0177] The large particle discharge pipe C10 is typically installed vertically or inclined downwards. A sealing blind flange C12 is installed at the end of the large particle discharge pipe C10 via a sealing clamp assembly. When discharge is required, the clamp can be quickly loosened, the blind flange removed, and the large particles will automatically discharge under gravity. After cleaning, the blind flange is reinstalled and the clamp is tightened to restore the seal.

[0178] A vibrating screening device according to this application includes: The feeding control assembly includes a chute discharge roller B4, which is used to control the amount of powder fed. An automated vibrating screening assembly is located below the feeding control assembly. The automated vibrating screening assembly includes a screening chamber and a vibration assembly. The screening chamber is equipped with a diversion screen C7. The vibration assembly includes at least one pneumatic vibrator C2 installed on the screening chamber. The pneumatic vibrator C2 is used to apply vibration to the diversion screen C7.

[0179] The core function of the feeding control component is to precisely regulate the powder flow rate entering the screening stage, avoiding instantaneous overload and ensuring the stability of screening quality. The inclined chute discharge roller B4 is a horizontally placed cylindrical roller with 3-6 evenly spaced spiral grooves along its axial direction on its surface. The groove depth is 1.5-2 times the powder particle size. Both ends of the roller are fixed to a support frame via bearing seats, and one end is connected to a frequent start motor B1. The output shaft of the frequent start motor B1 drives the roller to rotate via coupling B3. By adjusting the speed of the drive motor, the rotational speed of the roller can be changed, thereby controlling the amount of powder falling into the screening chamber per unit time.

[0180] The powder screening chamber is a rectangular box with an open top, a feed inlet at the top, and two independent discharge outlets at the bottom. A flow-diverting screen C7 is installed inside the screening chamber.

[0181] According to one embodiment of this application, the feeding control component includes a frequent start motor B1, which drives the chute discharge roller B4 to rotate intermittently or continuously.

[0182] According to one embodiment of this application, the feeding control component includes a sealing structure disposed between the inclined chute feeding roller B4 and the powder screening chamber to prevent powder leakage and external gas entry during the feeding process.

[0183] According to one embodiment of this application, the material feeding control component includes a material feeding bin housing B5, a chute material feeding roller B4 rotatably connected inside the material feeding bin housing B5, and a felt sealing ring B8 and an end face sealing ring B9 are provided at the movement gap between the chute material feeding roller B4 and the material feeding bin housing B5.

[0184] According to one embodiment of this application, the automated vibrating screening assembly includes a pressure spring C3, one end of which is connected to the screening chamber and the other end is connected to the equipment frame C5. The pressure spring C3 is used to support the screening chamber. When the pneumatic vibrator C2 applies vibration to the diversion screen C7, the screening chamber as a whole vibrates relative to the equipment frame C5.

[0185] According to one embodiment of this application, each pneumatic vibrator C2 is provided with a corresponding pressure regulating valve, and the input air pressure of each pressure regulating valve is adjustable.

[0186] According to one embodiment of this application, the diversion screen C7 is provided with a powder sieving section C14 and a separation section C15. The powder sieving section C14 is used to allow powder that meets the preset particle size requirements to pass through, and the separation section C15 is used to allow powder that is larger than the preset particle size to pass through. Baffle C20 is connected to the diversion screen C7 and is located between the powder screening section C14 and the separation section C15; The diversion screen C7 and the baffle C20 divide the internal space of the powder screening chamber into a first cavity C16 and a second cavity C19. The first cavity C16 includes an upper cavity space C17 located above the diversion screen C7 and a large particle recovery cavity C18 located below the separation section C15. The second cavity C19 includes a qualified powder recovery cavity located below the powder screening section C14.

[0187] According to one embodiment of this application, the diversion screen C7 forms an angle with the horizontal plane, so that the powder on the sieving section C14 can slide along the screen surface to the separation section C15; the separation section C15 is constructed as a through slot, so that large particles of powder or impurities fall from the upper cavity space C17 into the large particle recovery cavity C18 through the through slot.

[0188] According to one embodiment of this application, an air blowing assembly is included, which includes at least one back-blowing nozzle installed in the powder screening chamber and facing the diversion screen C7.

[0189] According to one embodiment of this application, the automated vibrating screen assembly includes a gas control air path, the air path control mechanism being configured to provide at least two different pressures of gas to a backflush nozzle, the backflush nozzle spraying gas toward the diverting screen C7.

[0190] A vibrating screening device according to this application includes: Equipment frame C5; Vibrating screening system 3 is installed on equipment frame C5. The material collection system 4 is connected to the vibrating screening system 3 and is used to collect the powder after screening. The feeding system 1 and the unloading control system 2 are connected to the vibrating screening system 3 and are used to provide the powder to be screened to the vibrating screening system 3. The feeding system 1, the unloading control system 2, the vibrating screening system 3, and the collecting system 4 are connected in sequence and are sealed to each other through a sealing structure to form a closed space isolated from the external environment.

[0191] This embodiment provides a vibrating screening device, the core design of which is to integrate all functional systems and connect them through a sealed structure to form a closed space that is completely isolated from the external environment, thereby achieving efficient screening while completely preventing dust leakage and ensuring production safety and cleanliness.

[0192] The device mainly includes an equipment frame C5, and a feeding system 1, a discharging control system 2, a vibrating screening system 3, and a collection system 4 installed on it. These systems are connected in sequence to form a complete powder processing flow path.

[0193] The equipment frame C5 can be welded or bolted together from high-strength metal profiles (such as aluminum alloy or steel square tubing), providing a stable support foundation for the entire device. Vibration-damping pads or dampers can be installed at the bottom of the frame to absorb and isolate the vibrations generated during the operation of the vibrating screening system 3, ensuring the smooth operation of the device and reducing noise.

[0194] During operation, the powder to be screened is added to a sealed feeding hopper. After the device is started, the feeding mechanism transports the powder to the discharge control system 2. The discharge control system 2 opens and controls the feeding rate according to a preset program, and the powder enters the sealed screen box in a vibrating state. In the vibrating screening system 3, the powder is stratified by the screen according to particle size. Fine powder that meets the requirements passes through the screen, while coarser particles move along the screen surface and are discharged from different outlets. The screened powders of each grade fall into their corresponding collection containers through sealed pipes. The entire process is completed in a negative pressure or closed environment, with no dust escaping.

[0195] Through modular system design and comprehensive sealing connections, a complete closed powder processing environment is constructed, fundamentally solving the leakage and contamination problem in the sieving process; the coordinated operation of each system realizes full-process automation from feeding, metering, sieving to collection, resulting in high efficiency.

[0196] According to one embodiment of this application, the feeding system 1 includes a storage tank A6, which is connected to the unloading control system 2 below via a first pneumatic butterfly valve A4; The material feeding control system 2 includes a material feeding bin housing B5, and a chute material feeding roller B4 for quantitative material feeding is provided inside the material feeding bin housing B5; The vibrating screening system 3 includes a screening chamber, which includes a top cover C1, a bottom base C4, and a diversion screen C7. The diversion screen C7 is located between the top cover C1 and the bottom base C4. The material collection system 4 is connected to the lower base C4 of the powder screening chamber; The connection ports of the storage bin A6, the discharge bin shell B5, the top cover of the powder screening chamber C1, and the bottom base of the powder screening chamber C4 are all equipped with sealing grooves. The sealing grooves are fitted with sealing rings and are locked together by sealing clamps.

[0197] The feeding system 1 mainly includes a storage bin A6. This storage bin A6 serves as a buffer and temporary storage container for the powder to be screened. It has a top-mounted feeding port with a sealed cap, and a bottom discharge port connected to the inlet of the feeding control system 2 via a first pneumatic butterfly valve A4. The first pneumatic butterfly valve A4 acts as an on / off valve, its opening and closing driven by compressed air, providing rapid response and reliably cutting off or connecting the material flow. The discharge port end face of the storage bin A6 is machined with a sealing groove, within which a sealing ring (such as a silicone or fluororubber ring) is placed. After docking with the inlet flange of the first pneumatic butterfly valve A4, a sealing clamp assembly (e.g., consisting of two semi-circular clamps, a sealing gasket, and fastening bolts) is used to lock the two flange end faces, compressing the sealing ring to achieve a static seal. In some embodiments, a level gauge can be installed on the side wall of the storage bin A6 to monitor the material height in real time, providing alarms for insufficient or full material supply and signals for automated feeding.

[0198] The core of the feeding control system 2 is the feeding hopper housing B5, whose upper inlet is sealed to the outlet of the first pneumatic butterfly valve A4 via the aforementioned method. Inside the feeding hopper housing B5 is a crucial quantitative feeding mechanism—the inclined chute feeding roller B4. This feeding roller has one or more grooves (i.e., inclined grooves) of a specific volume cut along its axial direction. When the drive device (such as a servo motor) rotates the feeding roller, each groove fills with material as it passes the inlet, and when it rotates to the lower outlet, the material is discharged under gravity. By precisely controlling the rotation speed of the feeding roller, precise and continuous quantitative feeding of powder can be achieved, solving the problem of unstable feeding flow in traditional valves. The lower outlet of the feeding hopper housing B5 also has a flange interface with a sealing groove.

[0199] The core of the vibrating screening system 3 is a sealed screening chamber. From top to bottom, the screening chamber mainly includes a top cover C1, a diversion screen C7, and a lower base C4.

[0200] The top cover C1 of the powder screening chamber is equipped with a feed inlet, and the inside of the top cover can be designed with a guide plate to ensure that the material is evenly dispersed.

[0201] The diversion screen C7 is installed between the top cover C1 and the lower base C4 of the sieving chamber and is the core component for particle size separation. Single or multiple layers of screens with different mesh sizes can be installed as needed. The screen is fixed and pressed between the top cover C1 and the lower base of the sieving chamber by an annular pressure frame and butterfly bolts. A sealing strip ensures the sealing of the screen edges, preventing coarse and fine powder from mixing.

[0202] The lower base C4 of the powder screening chamber is located at the bottom of the chamber, and has at least one discharge port on its bottom or side wall for discharging the screened powder. The entire powder screening chamber is mounted on the equipment frame C5 by elastic support components (such as rubber springs) and is driven by a vibration motor to generate high-frequency micro-amplitude vibration, enabling efficient separation of powder on the screen. An observation window can be provided on the top cover C1 or the lower base of the powder screening chamber. This observation window is made of high-strength transparent material (such as polycarbonate) and is sealed by an annular pressure cap and a sealing gasket, facilitating online observation of the screening status.

[0203] The upper end face of the top cover C1 of the powder screening chamber and the upper and lower end faces of the base C4 of the powder screening chamber are all machined with sealing grooves and embedded with sealing rings. When the top cover C1 and the base of the powder screening chamber are closed and clamp the diversion screen C7, their mating surfaces are sealed by the sealing rings; at the same time, their connection ports with external pipes (such as pipes from the discharge hopper shell B5 and pipes leading to the collection system 4) are all locked and connected by the aforementioned sealing clamp assembly.

[0204] The collection system 4 is connected below the base C4 of the sieving chamber. The outlet of the base C4 is connected to the collection interface via a sealed pipe. This collection interface is typically a quick-connect female connector with a pneumatic or manual on / off valve. The inlet of the collection container of the collection system 4 is equipped with a matching male connector. When material needs to be collected, the male connector is mated with the female connector and locked to form a sealed channel; after collection, the connection can be disconnected. Different outlets can accommodate powders of different fineness, achieving classified collection.

[0205] The powder to be screened is stored in storage bin A6. After the system starts, the first pneumatic butterfly valve A4 opens, and the powder falls into the discharge bin housing B5 of the feeding control system 2 under gravity. The inclined chute discharge roller B4 rotates at a set speed, continuously and evenly feeding a fixed amount of powder into the top cover C1 of the screening chamber of the vibrating screening system 3. The powder is screened by the diversion screen C7 in the screening chamber. Fine powder passes through the screen and falls into the fine powder outlet of the base C4 under the screening chamber, while coarse powder moves along the screen surface to the coarse powder outlet. The screened powders are then guided into different collection containers through the corresponding sealed pipes and collection interfaces below the base C4 of the screening chamber. The entire process is completed in a closed space consisting of storage bin A6, discharge bin housing B5, screening chamber, and connecting pipes. The sealing grooves, sealing rings, and sealing clamps at all connections effectively prevent powder from escaping, achieving clean and efficient automated screening operations.

[0206] According to one embodiment of this application, the top of the storage box A6 of the feeding system 1 is provided with a top cover A1 of the feeding hopper A2 and a first material level sensor A5; the collecting system 4 includes a collecting bucket D4 and a second material level sensor D5, and the collecting bucket D4 is connected to the lower base C4 of the powder screening chamber through a bellows D3 and a second pneumatic butterfly valve D1; the first material level sensor A5 and the second material level sensor D5 are used to detect the material level and trigger the opening and closing signal of the second pneumatic butterfly valve D1.

[0207] The material storage bin A6 of the feeding system 1 is equipped with a top cover A1 for a feeding hopper A2. This top cover is connected to the material storage bin A6 via a hinge or a sliding guide rail, and can be equipped with a pneumatic or electric actuator to drive its opening and closing. A sealing strip can be provided between the contact surfaces of the top cover and the material storage bin A6 to ensure a tight seal when closed.

[0208] The storage bin A6 has a first level sensor A5 installed on its internal side wall or top. This sensor can be a radar level gauge, a radio frequency capacitive level gauge, or an ultrasonic level gauge, used to detect the powder level height inside the storage bin A6 in real time and accurately.

[0209] The collection hopper D4 is used to finally hold the sieved powder. The corresponding discharge port of the base C4 under the sieve chamber is connected to the second pneumatic butterfly valve D1 and the bellows D3 in sequence through pipes, and finally connected to the inlet of the collection hopper D4.

[0210] The second pneumatic butterfly valve D1 is the on / off valve of the material collection channel, controlling the opening and closing of the powder flowing into the material collection bucket D4.

[0211] The bellows D3 can be made of metal or plastic. One end is connected to the outlet of the second pneumatic butterfly valve D1 via a sealing clamp assembly, and the other end is connected to the collection bucket D4 via a similar sealing interface. The flexibility of the bellows D3 can effectively seal the material and buffer and isolate the vibration of the screening chamber from the direct impact on the downstream collection bucket D4, while also facilitating the placement and positioning of the collection bucket D4.

[0212] A second level sensor D5 is installed inside or on top of the collection hopper D4. Its type and function are similar to those of the first level sensor A5. It is used to monitor the material height in the collection hopper D4 in real time to prevent overfilling and overflow.

[0213] The first level sensor A5 and the second level sensor D5 constitute the key sensing unit of the device. Their detection signals are directly used to trigger the opening and closing of the relevant second pneumatic butterfly valve D1 to achieve closed-loop control. The specific logic is as follows: When the first level sensor A5 detects that the material level in the storage bin A6 is lower than the set low threshold, the central control system can issue an audible and visual alarm, prompting the need for material replenishment, or trigger the automatic feeding mechanism (such as a vacuum feeder) to start, replenishing material at the top cover A1 of the upper hopper A2. When the material level reaches the set high threshold, material replenishment automatically stops. This ensures continuous material supply and avoids empty bins.

[0214] When the second level sensor D5 detects that the material level in a collection hopper D4 has reached the set full threshold, the central control system immediately sends a signal to close the second pneumatic butterfly valve D1 on the corresponding pipeline, cutting off the powder flow and preventing overflow. Simultaneously, a warning signal can be issued to notify the operator to replace the collection hopper D4. After the empty hopper is in place, the pneumatic butterfly valve is reopened to continue collecting.

[0215] After the system starts, if the first material level sensor A5 indicates sufficient material, the first pneumatic butterfly valve A4 opens, and the powder enters the feeding control system 2. The inclined chute discharge roller B4 feeds the powder quantitatively at a set speed, and the powder enters the vibrating screening system 3 for screening. The qualified powder after screening passes through the outlet of the base C4 under the screening chamber, and falls into the designated collection bucket D4 through the opened second pneumatic butterfly valve D1 and bellows D3. Throughout the process, the second material level sensor D5 monitors the material level in real time. When the material level is detected to be full, the second pneumatic butterfly valve D1 in this passage is immediately closed, and the powder flow is temporarily interrupted before the valve. After the operator replaces the collection bucket D4, the valve is reopened, and the process continues. All connections, especially both ends of the bellows D3, are sealed with sealing clamps to ensure a tight seal, and the entire material path remains closed at all times.

[0216] In one embodiment, the additive screening device includes a vibrating screening system 3 (the vibrating screening component mentioned above), and also integrates a feeding system 1, a discharging control system 2, and a collecting system 4, forming a fully automatic, closed powder processing unit.

[0217] Reference Figures 1 to 7 The feeding system 1 mainly includes a feeding hopper top cover A1, a feeding hopper A2, a first sealing clamp assembly A3, a first pneumatic butterfly valve A4, a material level sensor A5, and a storage tank A6. This system is used to safely and securely add the powder to be screened into the device, and achieves automatic feeding control through the first pneumatic butterfly valve A4 and the material level sensor A5. The bottom of the storage tank A6 has a groove for placing a sealing ring, used to achieve inert gas sealing and prevent powder leakage when connected to the bottom feeding structure; the structure is connected using sealing clamps, which facilitates maintenance and reduces manufacturing costs; the first pneumatic butterfly valve A4 is installed in the middle, which can automatically open and close according to a signal, with rapid response and good sealing performance; the material level sensor A5 is located on the top of the storage tank A6. When the material level in the storage tank A6 exceeds the material level sensor A5, a signal is sent to close the first pneumatic butterfly valve A4, and the signal is manually cleared after the material level decreases.

[0218] Reference Figures 1 to 7 The material feeding control system 2 mainly includes a frequent start motor B1, a motor bracket B2, a coupling B3, a chute discharge roller B4, a discharge bin housing B5, a left end cover B6, a sealed bearing B7, a felt sealing ring B8, an end face sealing ring B9, and a right end cover B10. Located below the storage bin A6, the material feeding control system 2 uses the motor-driven chute discharge roller to evenly and quantitatively distribute the powder onto the distribution screen C7 below, preventing localized accumulation. The top and bottom surfaces of the discharge bin housing B5 have grooves for placing sealing rings, which are used to achieve inert protective gas sealing and prevent powder leakage when connecting other structures. The feeding control system 2 uses a chute discharge roller B4 in conjunction with a frequently starting motor B1 for feeding. This design makes it easy to control the amount of material fed each time and to distribute it evenly across the entire feeding projection area, avoiding local powder accumulation, which would cause impurities and large particles of waste powder to be compacted into the mesh, making cleaning difficult. The movement gap between the chute discharge roller B4 and the discharge bin housing B5 is sealed with a felt sealing ring B8 and an end face sealing ring B9, and a bearing with a sealing cap is used to prevent powder from contaminating the bearing, causing movement to become stiff and protective gas to leak.

[0219] Reference Figures 1 to 7The vibrating screening assembly 3 mainly consists of the top cover of the screening chamber C1, the pneumatic vibrator C2, the pressure spring C3, the lower base of the screening chamber C4, the equipment frame C5, the pressure relief connector C6, the diversion screen C7, the conical backflush nozzle C8, the protective air connector C9, the large particle discharge pipe C10, the second sealing clamp assembly C11, the sealing blind plate C12, and the oxygen content sensor C13. The top and bottom of each component—the sieving chamber top cover C1, the sieving chamber base C4, the diversion screen C7, and the large particle discharge pipe C10—have grooves for installing sealing rings. These grooves are used to achieve inert gas sealing and prevent powder leakage when connecting to other structures. After installation, the diversion screen C7 forms an angle of approximately 15° with the horizontal, allowing powder to slide down the screen surface during vibration. The internal situation can be observed through the explosion-proof glass of the sieving chamber top cover C1, and it is supported at the four corners by four relatively rigid pressure springs C3 to amplify the vibration. The diversion screen C7... Three pneumatic vibrators C2 are mounted on the side. The overall vibration intensity of the pneumatic vibrators C2 can be adjusted by changing the air pressure, and the activation position can be used to control the vibration of a localized area. The gas pipeline connection sequence is: compressed air source, filter, direct-acting solenoid valve, pressure regulating valve assembly, and pneumatic vibrator. The signal line connection sequence is: time relay, oxygen content sensor, and direct-acting solenoid valve. By setting the time relay, the pneumatic vibrators C2 can be set to start and stop at specific times, and the buzzer inside the time relay assembly can be set to provide a timed reminder. Adjusting the pressure regulating valve can adjust the vibration force, with an adjustment range of 0.2-0.4 bar, achieving 100N ultrasonic excitation, which is convenient for screening large batches of powder.The dividing screen C7 is divided into a sieving zone and a separation zone. The sieving zone uses a taut screen for sieving, while the separation zone has a through-hole that allows larger powder particles to roll off the screen. A baffle plate in the middle of the base C4 under the sieving chamber, located at the edge of the separation surface of the separating screen C7, divides the chamber into a qualified powder recovery chamber and a large particle recovery chamber. When the dividing screen C7 is vibrated, powder with a particle size matching the mesh size passes through the screen and enters the qualified powder recovery chamber, while waste powder or impurities larger than the mesh size slowly fall into the large particle recovery chamber. The waste powder and impurities are collected and discharged into the large particle discharge pipe C10. After the screening operation is completed, the second sealing clamp assembly C11 is opened and the sealing blind plate C12 is removed to collect and remove the large particle waste powder and impurities. The pressure relief connector C6 is used to discharge the internal gas and is connected to a direct-acting solenoid valve, which automatically controls the opening and closing according to the signal. In addition, there is a row of 5 sets of air blowing devices on the back of the base C4 under the screening chamber. Among them, the conical back-blowing nozzle C8 operates under a protective gas pressure of 0.5-0.7 Bar. With a flow rate of not less than 700 L / min and an air delivery angle of not less than 60°, this device is mainly used for backflushing screens to prevent clogging. For screening active metal powders, it can provide low-flow inert gas protection gas to improve operational safety. The gas path connection should include an inert gas source, filter, direct-acting solenoid valve, solenoid valve, pressure regulating valve, check valve, protective gas connector C9, and conical backflushing nozzle C8. The solenoid valve should be a three-position, five-way, center-closed solenoid valve with air intake at the center position and output... The left end is connected to a pressure reducing valve and a check valve, and the right end is connected to a booster valve and a check valve. Then, the two lines are combined using a three-way valve and connected to the protective gas connector C9. During gas washing, the signal line controls the normally open delayed disconnect button switch, oxygen content sensor, time relay, three-position five-way solenoid valve, and pressure reducing valve. During backflushing, the signal line controls the normally open normally open button switch, three-position five-way solenoid valve, and booster valve. The two control lines are interlocked, and a normally closed normally closed button switch is set as a stop control for overall control of the control system.

[0220] Reference Figures 1 to 7 The material collection system 4 mainly includes a second pneumatic butterfly valve D1, a third sealing clamp assembly D2, a bellows pipe D3, a collection hopper D4, and a material level sensor D5. This system is located below the qualified powder outlet and is used for the sealed collection of qualified powder after screening. The collection hopper D4 features a detachable design for easy emptying and cleaning. The material level sensor D5 monitors the amount of collected material; when the collection hopper is full, the system automatically stops feeding and prompts the operator to replace it. The bellows pipe D3 can be directly cleaned outdoors using compressed air and a non-woven fabric.

[0221] The working process of the additive screening device is as follows: Figure 6It achieves a high degree of automation: the entire process from feeding, air washing, powder screening, backflushing and screen cleaning to material collection can be carried out automatically in a closed environment, which greatly improves the stringent requirements of high efficiency, high quality and high safety for powder recycling and screening in the additive manufacturing field.

[0222] Reference Figures 8 to 11 In one embodiment, the vibrating screen is prepared before starting the screening operation. This step specifically includes: Check the power connection of the device and whether the protective gas (e.g., argon) supply is normal.

[0223] Inspect the inside of the equipment, especially the chambers, pipes, valves, and barrels through which the powder flows, to ensure they are clean and free of cross-contamination.

[0224] Install the clean collection hopper D4 beforehand and check that all sealing clamp components are locked in place to ensure the system's airtightness.

[0225] Power on the equipment and test the inflation function (washing mode) and backflushing function in sequence through the controller interface to ensure they are normal. Also, confirm that the initial reading of the oxygen content sensor C13 is within the normal range.

[0226] After receiving the feeding command from the operator, the controller enters the feeding stage.

[0227] The operator adds the powder to be screened one by one through the feeding hopper A2.

[0228] The feeding process continues until the material level sensor A5 in the storage bin A6 detects that the bin is full and issues a prompt, or until all the powder to be screened has been added.

[0229] After feeding is completed, any powder that may remain in the feeding hopper A2 should be collected, and the feeding port should be covered with the top cover A1 of the feeding hopper or other cover plates to maintain the airtightness of the system.

[0230] Upon receiving the start screening command, the controller initiates the automatic screening program. This program may include one or more of the following sub-steps: Automatic gas scrubbing: The equipment first executes a gas scrubbing procedure, in which the blowing assembly blows protective gas into the sieving chamber in "gas scrubbing mode" until the oxygen concentration in the chamber, as measured by the oxygen content sensor C13, is lower than a preset safety threshold (for example, the preset safety threshold oxygen concentration is set to 2%). This step aims to provide an inert atmosphere to protect the active metal powder and prevent it from being oxidized during the sieving process.

[0231] Automatic powder sieving: Once the oxygen concentration reaches the standard, the controller activates the feeding control system 2 and the vibration component, and the powder begins to fall evenly from the storage bin A6 onto the vibrating diverting screen C7 for sieving. This process requires no operator supervision.

[0232] Online screen cleaning: It is understandable that for tasks requiring prolonged screening, the screen located directly below the material feeding area is at risk of clogging due to continuous impact and compression from the powder. To address this issue, this method includes an online screen cleaning step. This step can be manually triggered by the operator through the observation window C11 on the top cover of the screening chamber, or it can be automatically triggered by the controller based on a preset working time.

[0233] When online screen cleaning is triggered, the controller pauses the feeding and screening operations and automatically activates the "back-blowing mode" of the air blowing component.

[0234] In a specific example, each backflush nozzle C8 sprays a high flow rate of protective gas (preferably argon) onto the lower surface of the diversion screen C7, for example, at a pressure of 0.4 MPa, achieving a spray angle of not less than 60° and a gas flow rate of not less than 350 L / min, to efficiently clean the diversion screen.

[0235] After backflushing, the equipment undergoes another gas scrubbing process. Once the oxygen content in the screening chamber reaches the required level again, the operator manually presses the reset button on the controller, or the controller automatically resumes material feeding and screening operations. This step, using high-pressure gas pulses, effectively solves the problem of online screen clogging, ensuring screening efficiency and continuity.

[0236] During the screening process, the controller monitors the amount of qualified powder collected in real time through the material level sensor D5 set at the collection hopper D4.

[0237] When the level sensor D5 detects that the collected amount has reached the set upper limit of the warning value, the controller automatically stops feeding and issues a full material prompt.

[0238] After responding to the prompt, the operator manually opens the sealing clamp assembly D2 on the top of the collection bucket D4, and after depressurizing (e.g., waiting 3-5 minutes), safely removes the full collection bucket.

[0239] After replacing the waste collection hopper with a new one and locking it, the operator manually presses the reset button, the controller resumes feeding, and the screening operation continues. This automated monitoring and pause function prevents powder spillage and enables seamless operation during continuous operation.

[0240] Once all the preset screening tasks are completed, the controller automatically stops all operating components.

[0241] The operator depressurizes and removes the collection bucket D4 to recover the qualified circulating powder that has been screened.

[0242] It is understandable that some floating powder will remain in the screening chamber, and it is necessary to wait for it to settle naturally (for example, wait for about 10 minutes). After the operator confirms through the observation window that there is no obvious floating powder, the sealing clamp assembly at the large particle discharge pipe C10 is opened, the sealing blind plate C12 is removed, and the large particle waste powder and other impurities that failed to pass through the screen inside the discharge pipe are cleaned and collected, and then stored separately.

[0243] In a preferred embodiment, to avoid mixing powders of different grades and affecting product performance, it is recommended that each grade of material powder be equipped with an independent sieving device.

[0244] If conditions do not permit, the equipment must be thoroughly cleaned when switching to screen different grades of materials. The main components requiring cleaning include all structural parts through which the powder flows, such as the feeding hopper A2, storage bin A6, discharge hopper shell B5, screening chamber, large particle discharge pipe C10, and collection bucket D4.

[0245] At the same time, it is necessary to replace the existing screen with a dedicated diversion screen C7 that is compatible with the new material.

[0246] It is understood that this invention, through a piston-type pneumatic vibrator and a diversion channel, can achieve automatic sieving of additive manufacturing circulating powder and removal of large particulate impurities from the screen, thereby improving sieving efficiency, ensuring production safety, and eliminating the need for workers to constantly monitor the status, reducing the labor intensity of workers, and avoiding dust pollution to the environment and physical injury to operators.

[0247] This invention uses an automatic feeding control system to precisely control the quantity and timing of feeding, thereby improving the overall automation level of the machine and avoiding frequent screen clogging caused by the inability to adjust the feeding.

[0248] This invention allows manual adjustment of the overall tilt of the sieving chamber according to the flow characteristics of different powder grades, such as angle of repose and Hall velocity, thereby improving sieving efficiency and timely diverting and removing large particles and impurities.

[0249] This invention enables screening operations with different vibration intensities and frequencies through time relays and solenoid valves. It can also achieve timed start-up and shutdown or autonomous control of actions based on the equipment's working environment (material level and oxygen content) and status, thereby improving the level of automation.

[0250] The machine is equipped with back-blowing and air-washing functions; the back-blowing function ensures that the diversion screen can be cleaned without disassembling the machine during long-term powder screening operations; the air-washing function improves the safety of screening powders with strong activity.

[0251] Understandably, this application uses a pneumatic vibrator in conjunction with a diversion channel for powder sieving, improving powder cleaning efficiency and reducing the frequency of worker cleaning and screen replacement. Automatic powder cleaning eliminates the need for constant manual monitoring. The equipment reduces dust pollution and avoids the health risks associated with traditional manual powder sieving, while facilitating powder recycling and the recovery of powder from different materials. The device can flexibly adjust the tilt angle according to powder flow characteristics, preventing powder from accumulating in the same position for extended periods and promoting powder flow on the inclined screen surface, thus improving sieving efficiency. This device maximizes automation and flexibility while maintaining low cost, including the ability to set sieving time, adjust vibrator frequency and intensity, and perform manual backflushing. It also features an automatic control and judgment logic system that identifies environmental factors and automatically performs critical safety control actions.

[0252] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A vibrating screening assembly, characterized in that, include: Equipment frame (C5); A pressure spring (C3), the first end of which is connected to the equipment frame (C5); The powder screening chamber includes an upper cover (C1), a lower base (C4), and a diversion screen (C7). The diversion screen (C7) is located between the upper cover (C1) and the lower base (C4) of the powder screening chamber, and is connected to the second end of the pressure spring (C3). A vibration assembly, comprising a pneumatic vibrator (C2) for driving the diversion screen (C7) to vibrate; An air blowing assembly, the air blowing assembly including a back-blowing nozzle (C8) mounted at least one of the lower base (C4) of the powder screening chamber and the upper cover (C1) of the powder screening chamber, and facing the diversion screen (C7).

2. The vibrating screen assembly according to claim 1, characterized in that, The number of pneumatic vibrators (C2) is at least three, and the pneumatic vibrators (C2) are evenly distributed on the side of the diversion screen (C7).

3. The vibrating screen assembly according to claim 2, characterized in that, Each of the pneumatic vibrators (C2) is provided with a corresponding pressure regulating valve, and the input air pressure of each pressure regulating valve is adjustable.

4. The vibrating screen assembly according to claim 3, characterized in that, It includes a controller for controlling the opening and closing of pneumatic vibrators (C2) at different positions, and for controlling the input air pressure of different pressure regulating valves.

5. The vibrating screen assembly according to claim 1, characterized in that, The diversion screen (C7) has a connector on its side, which is connected to the second end of the pressure spring (C3).

6. The vibrating screen assembly according to claim 5, characterized in that, The diversion screen (C7) is supported by the pressure spring (C3) and forms a 15° inclined angle with respect to the horizontal plane, so that the powder slides down the screen surface under vibration.

7. A method for controlling vibrating screening, applied to a vibrating screening assembly as described in any one of claims 1-6, characterized in that, Includes the following steps: The vibration assembly is activated to cause the diversion screen (C7) to vibrate in order to sieve the powder; According to preset conditions, the air blowing component is controlled to blow air onto the screen.

8. The control method for vibrating screen according to claim 7, characterized in that, The step of activating the vibration assembly to vibrate the diversion screen (C7) for sieving the powder includes: The vibration force of at least one of the pneumatic vibrators (C2) is adjusted according to the powder collection speed.

9. The control method for vibrating screening according to claim 7, characterized in that, The step of controlling the air blowing assembly to blow air onto the screen according to preset conditions includes: When inert gas protection is required for the screen, gas washing control is performed, causing the blowing device to blow inert gas onto the screen at a first pressure and flow rate. When it is necessary to clean the clogged screen, backflush control is executed, causing the blowing device to blow gas onto the screen at a second pressure and flow rate, wherein the second pressure is greater than the first pressure.

10. A vibrating screening device, characterized in that, include: The vibrating screening assembly according to any one of claims 1 to 9.

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