A dust filtering device for food chemical industry raw material pneumatic conveying process

Abstract

The present application relates to the technical fields of dust filtration and gas-solid separation, and discloses a dust filtration device for food chemical raw material pneumatic conveying process, which comprises a filter shell and an alternating filter assembly arranged in the filter shell. The alternating filter assembly comprises a middle moving seat, two groups of filter material plates and a switching shell. When the middle moving seat moves, the two groups of filter material plates are in a folded state and an unfolded state respectively. The air passage on the switching shell corresponds to the folded side, and the dust collection groove corresponds to the unfolded side. The switching shell can synchronously switch the working states of the two sides. The device is further provided with a vibration dust removal assembly for vibrating and cleaning the filter material plates on the unfolded side. The present application can form a larger effective filtration area in a limited filtration space in the folded state, and provide a cleaning space in the unfolded state, so as to realize the alternating filtration and cleaning of the two groups of filter material plates, reduce the downtime maintenance, and improve the continuity and cleaning efficiency of dust filtration in the pneumatic conveying process.

Description

Technical Field

[0001] This invention relates to the field of dust filtration and gas-solid separation technology, and in particular to a dust filtration device for pneumatic conveying of food and chemical raw materials. Background Technology

[0002] In the production, transportation, and processing of food and chemical raw materials, pneumatic conveying is often used to transport powdery or granular raw materials in order to improve conveying efficiency and reduce manual handling. During the process of airflow carrying materials and materials entering receiving equipment, some small-sized raw material particles are prone to forming dust-laden gas with the airflow. Therefore, it is usually necessary to install filter devices at the corresponding exhaust positions so that the gas can be discharged after passing through the filter material and the dust entrained in it can be intercepted to reduce material loss and pollution caused by dust directly entering the production environment or external environment. At the same time, it is also conducive to maintaining the cleanliness of the production area.

[0003] In existing filtration devices for treating such dusty gases, the filter media is usually placed in a relatively fixed filtration position. As the dusty gas continuously passes through the filter media, dust gradually adheres to and accumulates on the surface of the filter media, increasing airflow resistance. Therefore, the filter media needs to be cleaned or maintained regularly. When the cleaning space is limited or the filter media is always in the filtration airflow channel, it is often necessary to suspend the filtration operation for cleaning, disassembly, or replacement, which can easily affect the continuous pneumatic conveying process. Although it is possible to maintain the filtration operation by adding a backup filter structure, this will correspondingly increase the space occupied by the equipment and the structural configuration. Therefore, there is still room for further improvement in how to balance a large effective filtration area and the operating space required for filter media cleaning within a limited filtration space, while ensuring that the filtration and cleaning processes can be carried out relatively continuously. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that existing dust filtration devices are difficult to balance a large effective filtration area and the space required for filter media cleaning within a limited filtration space. Cleaning and maintenance can easily cause filtration operations to be interrupted, affecting the continuity of the pneumatic conveying process. Therefore, we propose a dust filtration device for the pneumatic conveying process of food and chemical raw materials.

[0005] To achieve the above objectives, this application adopts the following technical solution: a dust filtration device for pneumatic conveying of food chemical raw materials, comprising a filter housing, an air inlet and an air outlet provided on the filter housing, and an alternating filtration assembly provided inside the filter housing;

[0006] The alternating filtration assembly includes a mounting frame, a central movable seat, two sets of filter media plates, and a switching housing. The central movable seat is horizontally slidably mounted on the mounting frame. The two sets of filter media plates are respectively mounted on both sides of the central movable seat. Each set includes multiple filter media plates that are sequentially and movably connected. The end of each set of filter media plates away from the central movable seat is movably connected to the filter housing, while the end closer to the central movable seat is driven by the central movable seat. When the central movable seat moves horizontally, one set of filter media plates folds and the other set of filter media plates unfolds. In the folded state, a gap is maintained between adjacent filter media plates for gas to pass through.

[0007] The switching shell is rotatably located in the lower inner cavity of the filter housing. One end of the switching shell is provided with a ventilation channel, and the other end opposite the ventilation channel is provided with a dust collection groove. The switching shell is connected to the middle moving seat by a transmission, and is configured such that when the switching shell is rotated to the working position, the ventilation channel corresponds to the folded filter material plate and is connected to the air inlet, and the dust collection groove corresponds to the bottom of the unfolded filter material plate.

[0008] Preferably, multiple connecting seats are slidably arranged on the mounting frame. Multiple filter media plates on the same side are divided into multiple groups through the connecting seats. Each group includes two filter media plates. The two filter media plates in the same group are rotatably connected at their closest ends, and their far ends are rotatably connected to the central moving seat, the filter housing, or an adjacent connecting seat, respectively.

[0009] Preferably, push rods are provided on the side of the central movable seat and the side of the connecting seat away from the central movable seat. When the central movable seat moves to the corresponding side, the push rod on the central movable seat pushes the adjacent connecting seat to move, and the push rod on the connecting seat pushes the next connecting seat in sequence.

[0010] Preferably, the connecting seat is provided with a limiting protrusion for limiting the unfolding angle of the filter media plate. When the filter media plate is in the unfolding limit position, the connection position of the adjacent filter media plates is pre-deflected upward, so that an obtuse angle with a predetermined folding direction is formed between the adjacent filter media plates.

[0011] Preferably, the upper end of the switching housing is provided with a traction member that is offset from its rotation axis, and the bottom of the middle moving seat is provided with a groove. The traction member extends into the groove and is movably engaged with the groove to convert the rotation of the switching housing into the horizontal movement of the middle moving seat.

[0012] Preferably, the top outer edge of the ventilation duct and the dust collection tank are provided with a flexible or elastic sealing ring. When the switching shell is rotated to the working position, the sealing ring is in contact with the bottom wall of the mounting frame and the middle moving seat.

[0013] Preferably, an air baffle is provided at the top of the central movable seat, which separates the airflow areas above the two sets of filter media plates.

[0014] Preferably, the filter housing is further provided with a vibration dust removal component. The vibration dust removal component can generate vibration by the upward flow of gas after filtration by the folded filter media plates, and transmit the vibration mainly to the filter media plates in the unfolded state according to the folded and unfolded states of the two sets of filter media plates.

[0015] The vibratory dust removal assembly includes an impeller, an excitation shaft, a vibration isolation groove, an elastic element, and an eccentric wheel. The air baffle plate is provided with an installation groove, and the impeller is rotatably installed in the installation groove. The vibration isolation groove is located at the top of the central movable seat. The lower end of the air baffle plate is movably installed in the vibration isolation groove and connected to the inner wall of the vibration isolation groove through the elastic element. The excitation shaft is rotatably installed at the lower end of the air baffle plate and is connected to the impeller drive. The eccentric wheel is installed on the excitation shaft.

[0016] Traction L-plates are movably installed on both sides of the central movable seat. The filter material plate closest to the central movable seat is rotatably connected to the corresponding traction L-plate. The traction L-plate is provided with a groove corresponding to the end of the excitation shaft, and the end of the excitation shaft extends into the groove.

[0017] Preferably, the traction L-plate corresponding to the filter media plate in the unfolded state contacts the excitation shaft to form a vibration transmission connection, while the traction L-plate corresponding to the filter media plate in the folded state is separated from the excitation shaft.

[0018] Preferably, the blades of the impeller protrude from both sides of the baffle plate, and the rotation axis of the impeller is intersected with the direction of the upward airflow after filtration by the filter media plate, so that the filtered gas flowing upward on either side of the baffle plate can act on the impeller.

[0019] The technical effects and advantages of this invention are as follows:

[0020] In this invention, two sets of filter media plates that can switch between folded and unfolded states are configured. When one set is in the folded state for filtration, a larger actual filter media area can be concentrated within a smaller horizontal footprint, while maintaining airflow space between adjacent filter media plates for dust-laden gas to pass through. Simultaneously, the other set of filter media plates is in the unfolded state, fully opening up the original folded positions and the dust accumulation areas between adjacent filter media plates, providing space for dust to fall off and be collected. With the linkage between the switching shell and the central moving seat, the folding and unfolding states of the two sets of filter media plates, as well as the corresponding positions of the air duct and dust collection tank, can be switched simultaneously. This allows the two sets of filter media plates to alternately perform filtration and dust removal functions, thereby continuously filtering dust on one side while cleaning dust on the other side. This reduces the need for long-term downtime or frequent disassembly and maintenance due to filter media cleaning, and improves the continuity of dust filtration and equipment efficiency during pneumatic conveying.

[0021] In this invention, the filtered clean airflow drives the impeller to rotate, and vibration is generated through the excitation shaft and eccentric wheel. Simultaneously, the positional changes of the traction L-plates on both sides as the filter media plates fold and unfold allow the excitation shaft to selectively connect with the traction L-plates on the unfolded side to transmit vibration. This primarily transmits vibration to the unfolded filter media plates, causing the dust adhering to the filter media surface to detach and fall into the dust collection trough. Meanwhile, the traction L-plates on the folded filter side remain separated from the excitation shaft, and the transmission of vibration to the central moving seat and the filter media plates on the filter side is weakened by elastic elements. This reduces the re-raising and secondary entrainment of dust already trapped during filtration due to vibration, allowing the vibration cleaning target to automatically switch with the working state of the filter media plates on both sides. This improves the cleaning effect on the unfolded side while ensuring the stability of the filter side. Attached Figure Description

[0022] The disclosure of this invention is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings, the same reference numerals are used to refer to the same parts:

[0023] Figure 1 This is a schematic diagram of the structure of the present invention;

[0024] Figure 2 This is a structural diagram of the present invention in its disassembled state;

[0025] Figure 3 This is a schematic diagram of the internal structure of the present invention;

[0026] Figure 4 This is a structural diagram of the present invention with the switching shell and mounting frame in a disassembled state;

[0027] Figure 5 This is a schematic diagram of the filter material plate and the central movable seat of the present invention in a disassembled state with the mounting frame.

[0028] Figure 6 For the present invention Figure 5 A structural diagram from the bottom perspective;

[0029] Figure 7 This is a schematic diagram of the structure of the connector and filter media plate in the connected state of the present invention;

[0030] Figure 8 This is a schematic diagram of the structure of the present invention with the traction L-plate and the middle moving seat separated.

[0031] Figure 9 This is a cross-sectional structural diagram of the central movable seat of the present invention;

[0032] Figure 10 This is a schematic diagram of the structure of the excitation shaft, impeller, and air baffle plate of the present invention in a disassembled state.

[0033] Legend: 1. Filter housing; 2. Air inlet; 3. Air outlet; 4. Switching housing; 5. Air duct; 6. Dust collection tank; 7. Air baffle plate; 8. Mounting frame; 9. Filter media plate; 10. Traction component; 11. Impeller; 12. Central moving seat; 13. Traction L-plate; 14. Connecting seat; 15. Push rod; 16. Groove; 17. Vibration shaft; 18. Mounting through groove; 19. Vibration isolation groove; 20. Elastic component; 21. Eccentric wheel. Detailed Implementation

[0034] It is readily understood that, based on the technical solution of this invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solution of this invention.

[0035] Reference Figures 1-10 As shown, the present invention provides a technical solution: a dust filtration device for pneumatic conveying of food and chemical raw materials, comprising a filter housing 1, an outlet 3 disposed at the upper end of the filter housing 1, and an inlet 2 disposed at the lower end of the filter housing 1. This device can be installed at the location in the pneumatic conveying system for food and chemical raw materials where gas-solid separation or end-of-line dust removal is required. The inlet 2 can be connected to the pneumatic conveying pipeline or the dust-laden exhaust pipeline of the corresponding receiving equipment. The power required for airflow can be provided by the air supply equipment, induced draft equipment, or negative pressure suction equipment configured in the pneumatic conveying system itself, so that the dust-laden gas carrying fine powder and dust of food and chemical raw materials during the conveying process enters the filter housing 1 through the inlet 2. The clean gas formed after filtration of the dust-laden gas is discharged through the outlet 3. The outlet 3 can be connected to the subsequent exhaust pipeline, fan inlet, or further purification equipment according to the on-site process requirements, so as to reduce the dust pollution caused by the dust generated during the pneumatic conveying process directly entering the working environment or the external environment.

[0036] An alternating filtration assembly is provided in the filter housing 1. In a preferred embodiment of the present invention, the alternating filtration assembly includes a mounting frame 8 installed in the inner cavity of the filter housing 1. A central movable seat 12 is horizontally slidably connected to the mounting frame 8. Specifically, a guide rail can be provided to achieve a stable sliding connection. Multiple filter media plates 9 connected in series are movably connected to both sides of the central movable seat 12. One end of the filter media plate 9 farthest from the central movable seat 12 is movably connected to the inner wall of the filter housing 1. The filter media plate 9 closest to the central movable seat 12 is connected to the corresponding side of the central movable seat 12 and is driven by the central movable seat 12. Adjacent filter media plates 9 are movably connected to each other. Multiple filter media plates 9 located on the same side of the central movable seat 12 can be folded or unfolded together, and are configured such that when multiple filter media plates 9 on one side are in a folded state, multiple filter media plates 9 on the other side are in an unfolded state.

[0037] In this invention, the folding state of the filter media plate 9 is not a stacking of multiple filter media plates 9 pressed together, but rather a sequential folding state with a certain included angle between multiple filter media plates 9, with an airflow gap between adjacent filter media plates 9 for the dust-laden gas to enter. Therefore, with the actual filtration area of ​​the filter media plate 9 itself remaining basically unchanged, the horizontal projection range occupied by multiple filter media plates 9 after folding is significantly reduced, thereby enabling a larger actual filter media area to be concentrated within the limited filtration station range inside the filter housing 1. The dust-laden gas can enter between adjacent filter media plates 9 and be filtered through multiple filter media surfaces. Thus, multiple filter media plates 9 on one side can form a larger effective filtration area with a smaller horizontal occupation range, while leaving space for the multiple filter media plates 9 on the other side to unfold.

[0038] When multiple filter media plates 9 are in the unfolded state, the included angle between adjacent filter media plates 9 increases, fully opening up the dust accumulation areas that were originally located in the folded position, creases, and between adjacent filter media plates 9. At the same time, the angle change that occurs when the filter media plates 9 change from the folded state to the unfolded state can cause some of the dust layer attached to the filter media surface to bend and crack, creating conditions for subsequent dust removal. The degree of mutual obstruction between adjacent filter media plates 9 after unfolding is reduced, and the detached dust can fall downwards more smoothly, making the unfolded state more suitable for dust removal. Based on the above structure, the filter media plates 9 on both sides can respectively undertake the functions of filtration and dust removal, and can exchange working states with the horizontal movement of the central moving seat 12, so that one side can filter while the other side can be cleaned, without the need for long-term shutdown and disassembly of the filter media plates 9 for routine dust removal operations.

[0039] In one specific embodiment, the filter media plate 9 may include a rigid outer frame with a certain structural strength and a filter media layer disposed within the rigid outer frame. The rigid outer frame is used to maintain the basic shape of the filter media plate 9 and form movable connection positions between it and adjacent filter media plates 9 and other structures. The filter media layer may be selected from fiber filter media, needle-punched filter media, membrane filter media, or other filter materials that can allow gas to pass through and trap dust particles, depending on the dust particle size, temperature, and material characteristics of the food and chemical raw materials being transported. In applications where there is a requirement for static electricity accumulation, filter media with corresponding antistatic properties may also be used. The rigid outer frame can reduce excessive deformation of the filter media layer during filtration pressure difference and folding and unfolding processes, so that each filter media plate 9 can maintain a relatively stable filtration shape.

[0040] The alternating filtration assembly also includes a switching shell 4 rotatably disposed in the lower inner cavity of the filter housing 1. One end of the switching shell 4 has a through-hole vent 5, and the opposite end has a dust collection groove 6. The vent 5 is always aligned with the folded filter media plate 9. A confluence space is formed between the bottom of the switching shell 4 and the bottom of the filter housing 1. The air inlet 2 corresponds to this confluence space, and the vent 5 is always connected to it, facilitating filtration of the gas to be filtered through the folded filter media plate 9 after entering the vent 5. The dust collection groove 6... The bottom of the filter media plate 9 in the unfolded state on the other side is used to correspond to the bottom of the filter media plate 9, which facilitates dust collection. Therefore, when the switching shell 4 is in any stable working position, the air passage 5, the folded filter media plate 9 and the air outlet 3 form the main filtration airflow path, while the dust collection groove 6 is located below the unfolded filter media plate 9 to form a corresponding dust collection area, so that the filtration airflow path and the dust collection area correspond to each other. The filter shell 1 is also equipped with a motor for driving the switching shell 4 to rotate, which is used when it is necessary to clean the filter media plate 9 on one side.

[0041] To increase the sealing between the air duct 5 and the dust collection tank 6 and the corresponding filter media plate 9, sealing rings are provided on the top outer edges of the air duct 5 and the dust collection tank 6. The sealing rings protrude from the top of the switching housing 4 and are flexible or elastic. The bottom of the middle moving seat 12 is flush with the bottom of the mounting frame 8. When the switching housing 4 is rotated into place, the sealing rings on the switching housing 4 can fit tightly against the bottom wall of the mounting frame 8 and the middle moving seat 12, thereby restricting the dust-laden gas entering the air inlet 2 from bypassing the air duct 5 and entering the upper part of the filter housing 1.

[0042] A V-shaped or lip-shaped flexible sealing structure can also be provided on the edge of the filter media plate 9 near the inner wall of the filter housing 1. Specifically, this can be achieved by forming a V-shaped or lip-shaped groove on the corresponding edge and providing a flexible sealing material. This flexible sealing structure can maintain sliding contact with the inner wall of the filter housing 1 during the folding and unfolding of the filter media plate 9. This not only provides room for movement when folding and unfolding the filter media plate 9, but also reduces the direct upward flow of dust-laden gas around the filter media from the edge gap between the filter media plate 9 and the filter housing 1.

[0043] To achieve regular folding or consistent folding angles for the filter media panels 9, a connecting seat 14 corresponding to the filter media panels 9 is slidably connected to the mounting frame 8. The connecting seat 14 divides multiple filter media panels 9 on the same side into multiple groups, with two filter media panels 9 in each group. The two filter media panels 9 in each group are rotatably connected at one end close to each other, and the other end is rotatably connected to the side of the central moving seat 12, the inner wall of the filter housing 1, or the connecting seat 14, thus forming a series connection. Push rods 15 are provided on the side of the central moving seat 12 and on the side of the connecting seat 14 away from the central moving seat 12. When multiple filter media panels 9 on one side need to be converted from an unfolded state to a folded state, the central moving seat 12 moves towards that side, first driving... The filter media plates 9 adjacent to it rotate relative to each other; as the central moving seat 12 continues to move, the push rod 15 on its side abuts against the nearest connecting seat 14 and pushes the connecting seat 14 to move along the mounting frame 8. Then, the push rod 15 on the connecting seat 14 continues to push the next connecting seat 14, and the movement of the central moving seat 12 is transmitted to the far end in sequence until the push rod 15 at the farthest position from the central moving seat 12 forms a limiting fit with the inner wall of the filter housing 1, thereby causing multiple filter media plates 9 on the same side to form a regular interval folded state in a predetermined direction; when the central moving seat 12 moves in the opposite direction, each connecting seat 14 is pulled open in sequence with the filter media plates 9, so that multiple filter media plates 9 on the corresponding side are unfolded again.

[0044] It should be noted that when the filter material plate 9 reaches its unfolded limit position, the adjacent filter material plates 9 are preferably not in a completely collinear horizontal dead point position, but rather their connection positions are kept in a slightly upward pre-deflected state, so that the adjacent filter material plates 9 form an obtuse angle that is close to unfolded but still has a predetermined folding direction. Specifically, a limiting protrusion corresponding to the filter material plate 9 can be provided on the connecting seat 14. The limiting protrusion restricts the filter material plate 9 from continuing to rotate to a completely horizontal position. Thus, when the middle moving seat 12 moves in the folding direction again and applies compression to the filter material plate 9, the adjacent filter material plates 9 can be stably folded up along the pre-formed upward deflection direction, avoiding multiple active connection points being in a nearly collinear state and forming a folding dead point, reducing the possibility of random downward folding, jamming, or inconsistent folding directions.

[0045] To achieve the horizontal displacement of the middle movable seat 12, a transmission connection can be established between the middle movable seat 12 and the rotation of the switching shell 4. Specifically, a traction member 10 can be provided at the upper end of the switching shell 4. The traction member 10 is offset from the axis of rotation of the switching shell 4. A groove 16 is provided at the bottom of the middle movable seat 12. The upper end of the traction member 10 extends into the inner side of the groove 16 and is movably connected to the groove 16. When the switching shell 4 drives the traction member 10 to rotate, the traction member 10 can achieve the horizontal displacement of the middle movable seat 12 through the groove 16. The traction member 10 can preferably be a roller rotatably provided at the top of the switching shell 4 to reduce friction. The groove 16 provides space for the traction member 10 to slide relative to the switching shell 4 during rotation, allowing the eccentric circular motion of the traction member 10 to... The central moving seat 12 is converted to reciprocating linear movement along the mounting frame 8. The traction component 10, groove 16, and switching shell 4 are configured such that when the switching shell 4 rotates 180 degrees, the central moving seat 12 is displaced to its limit distance, with multiple filter media plates 9 on one side in a folded state and multiple filter media plates 9 on the other side in an unfolded state. The air passage 5 corresponds to the folded filter media plate 9, and the dust collection groove 6 corresponds to the unfolded filter media plate 9. The same applies when the switching shell 4 rotates 180 degrees in the opposite direction. Thus, the switching of the filter air passage position, dust collection position, and the folded and unfolded states of the filter media plates 9 on both sides can be completed synchronously with only one rotation of the switching shell 4, avoiding asynchronous coordination caused by separate driving of the air passage switching and the filter media plate 9 state switching.

[0046] Furthermore, flexible sealing gaskets or sealing sheets can be provided at the movable connections between adjacent filter media plates 9, the movable connections between filter media plates 9 and the inner wall of the filter housing 1, and the movable connections between filter media plates 9 and the connecting seat 14 and the central movable seat 12. The sealing gaskets or sealing sheets have bending or overlapping allowances adapted to the movement range of the corresponding movable connections, so that during the relative rotation of the filter media plates 9, the sealing gaskets or sealing sheets can still span the connection gaps between adjacent components and remain in contact, without restricting the normal rotation of the filter media plates 9. This reduces the bypass flow path formed by dust-laden gas through each movable connection gap, increases the proportion of dust-laden gas passing through the filter media layer, and improves the overall filtration sealing performance.

[0047] An air baffle 7 is vertically installed at the top of the central movable seat 12. The air baffle 7 separates the airflow area above the filter material plates 9 on both sides of the central movable seat 12, so that the clean gas formed by the filter material plates 9 in the current folded state mainly flows upward along the corresponding side, which is convenient to be discharged from the air outlet 3.

[0048] In addition, the present invention also includes a vibration dust removal component. As a preferred embodiment, the vibration dust removal component includes an installation groove 18 disposed on the side wall of the air baffle 7. An impeller 11 is rotatably disposed inside the installation groove 18. The blades of the impeller 11 protrude from both sides of the air baffle 7. The rotation axis of the impeller 11 is intersected with the direction of the clean airflow flowing upward after being filtered by the filter media plate 9, preferably nearly perpendicular. Since the blades of the impeller 11 extend into both sides of the air baffle 7, the clean gas flowing upward on either side of the central moving seat 12 can act on the corresponding blades of the impeller 11 and drive the impeller 11 to rotate, regardless of which side of the filter media plate 9 is in a folded filtering state.

[0049] The vibration dust removal assembly also includes a vibration isolation groove 19 disposed on the top of the central movable seat 12. The lower end of the air baffle 7 extends to the inner side of the vibration isolation groove 19 and is movably connected to the vibration isolation groove 19. An elastic element 20 is disposed between the lower end of the air baffle 7 and the inner wall of the vibration isolation groove 19. An excitation shaft 17 is rotatably disposed on the lower end of the air baffle 7. The excitation shaft 17 is connected to the impeller 11. An eccentric wheel 21 is mounted on the excitation shaft 17. When the impeller 11 rotates, it drives the excitation shaft 17 and the eccentric wheel 21 to rotate. During the rotation, the eccentric wheel 21 generates a periodically changing centrifugal inertial force, causing the air baffle 7 and the excitation shaft 17 disposed thereon to vibrate within the range allowed by the elastic element 20. The vibration isolation groove 19 reserves a corresponding vibration space for the air baffle 7, while the elastic element 20 provides elastic support for the air baffle 7 on the one hand and reduces the direct transmission of vibration to the central movable seat 12 on the other hand.

[0050] The vibration dust removal assembly also includes traction L-plates 13 movably disposed on both sides of the central movable seat 12. The traction L-plates 13 can be displaced relative to the central movable seat 12 within a certain range, and the direction of displacement corresponds to the folding or unfolding direction of the filter material plate 9. The filter material plate 9 closest to the central movable seat 12 is rotatably connected to the side of the traction L-plate 13. The traction L-plate 13 is provided with a groove 16 corresponding to the end of the excitation shaft 17. The end of the excitation shaft 17 extends into the inside of the groove 16. The longitudinal height and transverse length of the groove 16 are both greater than the diameter of the excitation shaft 17, and the transverse length of the groove 16 is greater than its longitudinal height.

[0051] The grooves 16 on the two traction L-plates 13 and the travel of the traction L-plates 13 relative to the central moving seat 12 are configured as follows: when multiple filter media plates 9 on one side are in the unfolded state, the traction L-plate 13 on that side moves with the unfolding action of the filter media plates 9 to a position where the inner wall of the groove 16 contacts and fits against the end of the excitation shaft 17; while when multiple filter media plates 9 on the other side are in the folded state, the corresponding traction L-plate 13 moves to a position where a gap is formed between the inner wall of the groove 16 and the end of the excitation shaft 17; since the air baffle 7 is installed on the central moving seat 12 and moves synchronously with the central moving seat 12, and the two traction L-plates 13 on both sides are constrained by the folded and unfolded states of the corresponding filter media plates 9 respectively, when the central moving seat 12 completes one filtration station switch, the contact state between the two traction L-plates 13 and the excitation shaft 17 is automatically interchanged.

[0052] When the eccentric wheel 21 vibrates, the vibration of the excitation shaft 17 is first transmitted to the unfolded side traction L plate 13 that is in contact with it, and then transmitted by the traction L plate 13 to the multiple filter media plates 9 connected to it, causing the filter media plates 9 in the unfolded state to vibrate, thereby causing the dust adhering to the filter media surface and near the original folded position to fall off and fall into the dust collection trough 6 below; since the included angle between adjacent filter media plates 9 is large in the unfolded state, the degree of mutual shielding and mutual buffering of vibration between the filter media plates 9 is reduced, which is conducive to the transmission of vibration between the filter media plates 9 and the downward discharge of the fallen dust.

[0053] Meanwhile, the traction L-plate 13 on the folded filter side is separated from the excitation shaft 17, and the air baffle 7 and the middle moving seat 12 are isolated by the elastic element 20. Therefore, the excitation effect is difficult to be directly and significantly transmitted to the folded filter material plate 9 which is performing the filtration function. This makes the vibration on the filter side significantly less than that on the dust removal side. This can reduce the dust that has been trapped by the folded filter material plate 9 from being re-raised or being re-entrained due to vibration. At the same time, it can reduce the unnecessary cyclic vibration of the filter material plate 9 and its movable connection position during the filtration state. This is conducive to maintaining the shape of the filter material plate 9, the connection sealing state, and the stability of the filtered airflow during the filtration process.

[0054] The transmission connection between the excitation shaft 17 and the impeller 11 can specifically adopt a synchronous pulley and synchronous belt or a similar connection method. Specifically, corresponding synchronous pulleys can be set on the impeller 11 shaft and the excitation shaft 17, and a synchronous belt can be set between the corresponding synchronous pulleys, so that the rotation of the impeller 11 can realize the rotation of the excitation shaft 17. In addition to synchronous pulleys and synchronous belts, gear transmission or other mechanical transmission forms can also be used, provided that the impeller 11 can stably drive the excitation shaft 17 to rotate. This embodiment does not limit this to a single form.

[0055] The aforementioned elastic element 20 can preferably be a compression spring or a tension spring. There is a gap between the air baffle plate 7 and the inner wall of the vibration isolation groove 19 to facilitate the vibration of the air baffle plate 7. The middle moving seat 12 is less affected by vibration. The stiffness and quantity of the elastic element 20 can be selected according to the mass of the air baffle plate 7, the excitation shaft 17, the eccentric wheel 21 and the required dust removal amplitude, so that the air baffle plate 7 has stable support and can form vibration that meets the dust removal requirements under the periodic excitation action generated by the eccentric wheel 21.

[0056] Working principle: In use, taking the multiple filter media plates 9 on one side of the central movable seat 12 in a folded state and the multiple filter media plates 9 on the other side in an unfolded state as an example, the air passage 5 on the switching shell 4 is located below the folded filter media plates 9, and the dust collection tank 6 is located below the unfolded filter media plates 9. The dust-laden gas generated by the pneumatic conveying system enters the confluence space at the bottom of the filter shell 1 through the air inlet 2, and enters upward between the multiple folded filter media plates 9 through the air passage 5. Since the multiple filter media plates 9 are in a folded state, a large actual filter media area is formed within a small horizontal projection range. The dust-laden gas can pass through the filter media layer of each filter media plate 9, and the dust is trapped on the surface of the filter media. The filtered clean gas flows upward along the corresponding side of the air baffle 7 and is finally discharged from the air outlet 3.

[0057] During the filtration process, the upward-flowing clean gas acts on the impeller 11 and drives it to rotate. The impeller 11 drives the excitation shaft 17 and the eccentric wheel 21 to rotate through the transmission structure, thereby generating periodic vibration. At this time, the traction L plate 13 on the unfolded side maintains vibration transmission contact with the excitation shaft 17. The vibration is transmitted through the traction L plate 13 to the multiple unfolded filter media plates 9 on that side, causing the dust adhering to the surface of the filter media during the previous filtration process to gradually fall off and fall directly into the corresponding dust collection trough 6 below. The traction L plate 13 corresponding to the folded filter media plates 9 on the other side that are undergoing filtration remains separated from the excitation shaft 17, and with the vibration isolation effect of the elastic element 20, the vibration impact on the filtration side is reduced.

[0058] When the filter media plate 9 on the side currently performing the filtration function needs to be cleaned, the motor drives the switching shell 4 to rotate 180 degrees. During the rotation of the switching shell 4, the eccentrically set traction member 10 drives the central moving seat 12 to move horizontally along the mounting frame 8 through the groove 16 at the bottom of the central moving seat 12, so that multiple filter media plates 9 on the side that were originally in a folded state gradually unfold, while multiple filter media plates 9 on the other side that were originally in an unfolded state gradually fold. At the same time, the air passage 5 rotates with the switching shell 4 to the lower side of the newly formed folded side, the dust collection tank 6 rotates to the lower side of the newly formed unfolded side, and the contact state of the traction L plates 13 on both sides and the excitation shaft 17 also changes synchronously with the state change of the filter media plates 9, so that the vibration cleaning effect is automatically transferred to the newly formed unfolded side.

[0059] Therefore, in each stable working state, this device maintains a working relationship of folded filtration on one side and vibrating dust removal on the other side. The functions of the two sides can be interchanged through the linkage of the switching shell 4 and the central moving seat 12. The folded state is used to obtain a larger actual filter material area in a limited filtration space. The unfolded state is used to open the folds, reduce vibration buffering and dust blockage between adjacent filter material plates 9, and provide a smoother falling space for falling dust. At the same time, the filtration airflow provides driving force for the vibrating dust removal component, and the vibration transmission object can automatically switch according to the working state of the filter material plate 9. This reduces the long-term filtration interruption caused by the need to stop the machine to disassemble the filter material for dust removal in traditional filtration structures, and improves the continuity of dust filtration and dust removal maintenance in the pneumatic conveying of food and chemical raw materials.

[0060] The technical scope of this invention is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this invention, and all such modifications and variations should fall within the protection scope of this invention.

Claims

1. A dust filtration device for pneumatic conveying of food and chemical raw materials, characterized in that, It includes a filter housing, which has an air inlet and an air outlet, and an alternating filter assembly inside the filter housing; The alternating filtration assembly includes an installation frame, a central movable seat, two sets of filter media plates, and a switching shell. The central movable seat is horizontally slidably mounted on the installation frame. The two sets of filter media plates are respectively located on both sides of the central movable seat. Each set includes multiple filter media plates that are sequentially and movably connected. The end of each set of filter media plates away from the central movable seat is movably connected to the filter shell, while the end closer to the central movable seat is driven by the central movable seat. When the central movable seat moves horizontally, one set of filter media plates folds and the other set of filter media plates unfolds. In the folded state, a gap is maintained between adjacent filter media plates for gas to pass through. The switching shell is rotatably disposed in the lower inner cavity of the filter housing. One end of the switching shell is provided with a ventilation channel, and the other end opposite to the ventilation channel is provided with a dust collection groove. The switching shell is connected to the middle moving seat by transmission, and is configured such that when the switching shell is rotated to the working position, the ventilation channel corresponds to the folded filter material plate and is connected to the air inlet, and the dust collection groove corresponds to the bottom of the unfolded filter material plate.

2. The dust filtration device for pneumatic conveying of food and chemical raw materials according to claim 1, characterized in that: Multiple connecting seats are slidably arranged on the mounting frame. Multiple filter media plates on the same side are divided into multiple groups through the connecting seats. Each group includes two filter media plates. The two filter media plates in the same group are rotatably connected at their closest ends, and their far ends are rotatably connected to the central moving seat, the filter housing, or the adjacent connecting seat, respectively.

3. The dust filtration device for pneumatic conveying of food and chemical raw materials according to claim 2, characterized in that: Push rods are provided on the side of the central movable seat and on the side of the connecting seat away from the central movable seat. When the central movable seat moves to the corresponding side, the push rod on the central movable seat pushes the adjacent connecting seat to move, and the push rod on the connecting seat pushes the next connecting seat in sequence.

4. The dust filtration device for pneumatic conveying of food and chemical raw materials according to claim 3, characterized in that: The connecting seat is provided with a limiting protrusion for limiting the unfolding angle of the filter material plate. When the filter material plate is in the unfolding limit position, the connection position of the adjacent filter material plates is pre-deflected upward, so that an obtuse angle with a predetermined folding direction is formed between the adjacent filter material plates.

5. The dust filtration device for pneumatic conveying of food and chemical raw materials according to claim 1, characterized in that: The upper end of the switching shell is provided with a traction member that is offset from its rotation axis, and the bottom of the middle moving seat is provided with a groove. The traction member extends into the groove and is movably engaged with the groove to convert the rotation of the switching shell into the horizontal movement of the middle moving seat.

6. The dust filtration device for pneumatic conveying of food and chemical raw materials according to claim 1, characterized in that: The top outer edge of the ventilation duct and dust collection tank are provided with a flexible or elastic sealing ring. When the switching shell is rotated to the working position, the sealing ring is in contact with the bottom wall of the mounting frame and the middle moving seat.

7. The dust filtration device for pneumatic conveying of food and chemical raw materials according to claim 1, characterized in that: An air baffle is provided at the top of the central movable seat, which separates the airflow area above the two sets of filter media plates.

8. The dust filtration device for pneumatic conveying of food and chemical raw materials according to claim 7, characterized in that: The filter housing is also equipped with a vibration dust removal component. The vibration dust removal component can generate vibration by the upward flow of gas after filtration by the folded filter media plates. According to the folded and unfolded states of the two sets of filter media plates, the vibration is mainly transmitted to the unfolded filter media plates. The vibration dust removal assembly includes an impeller, an excitation shaft, a vibration isolation groove, an elastic element, and an eccentric wheel. The air baffle plate is provided with an installation groove, and the impeller is rotatably disposed in the installation groove. The vibration isolation groove is disposed at the top of the central movable seat. The lower end of the air baffle plate is movably disposed in the vibration isolation groove and connected to the inner wall of the vibration isolation groove through the elastic element. The excitation shaft is rotatably disposed at the lower end of the air baffle plate and is connected to the impeller drive. The eccentric wheel is disposed on the excitation shaft. Traction L-plates are movably arranged on both sides of the central movable seat. The filter material plate closest to the central movable seat is rotatably connected to the corresponding traction L-plate. The traction L-plate is provided with a groove corresponding to the end of the excitation shaft, and the end of the excitation shaft extends into the groove.

9. The dust filtration device for pneumatic conveying of food and chemical raw materials according to claim 8, characterized in that: When the filter media plate is in the unfolded state, the corresponding traction L-plate contacts the excitation shaft to form a vibration transmission connection; when the filter media plate is in the folded state, the corresponding traction L-plate separates from the excitation shaft.

10. The dust filtration device for pneumatic conveying of food and chemical raw materials according to claim 8, characterized in that: The blades of the impeller protrude from both sides of the baffle plate. The rotation axis of the impeller is intersected with the direction of the upward airflow after filtration by the filter media plate, so that the filtered gas flowing upward on either side of the baffle plate can act on the impeller.

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