A compact in-line pulse back-purge air filter equipped with a safety filter element

Abstract

The application discloses a compact series pulse back-flushing air filter equipped with a safety filter element, and belongs to the technical field of air filters. The compact series pulse back-flushing air filter equipped with the safety filter element is compact in structure, can solve the problem that the compact power cabin space of a special vehicle is difficult to replace a self-cleaning air filter, can realize the back-flushing self-cleaning function in the compact power cabin space of the special vehicle, and is equipped with the safety filter element. When air is filtered in a forward direction, the air flows into a main filter element shell from an air inlet pipe, and then is filtered by two stages of the main filter element and the safety filter element, and finally flows out from an air outlet of the safety filter element shell. When dust is back-flushed and cleaned, back-flushing air flows out from a nozzle and is discharged from a pressure relief port, so that the dust on the main filter element falls into a dust collecting hopper.

Description

Technical Field

[0001] This invention belongs to the field of air filter technology, specifically relating to a compact series pulse backflush air filter equipped with a safety filter element. Background Technology

[0002] As the first line of defense for the engine, the air filter is a crucial component that prevents dust and impurities from entering. Special vehicles often operate in extreme weather conditions, facing extremely harsh environments, especially in desert regions where high-powered diesel engines draw in very poor air quality. In such environments, dust concentrations are drastically higher than in conventional areas, posing a significant challenge to the entire air filtration system. This results in a rapid increase in intake system resistance, increased engine power loss, and impacts the vehicle's power and maneuverability. When the resistance reaches the engine's required limit, the engine must be stopped for manual cleaning and maintenance of the air filter. Frequent air filter maintenance reduces the effective service life of special vehicles, affects the reliability of the intake filtration system, and impacts vehicle performance, ultimately limiting the vehicle's continuous mobility.

[0003] In recent years, pulse-jet air filters, as a type of long-life, maintenance-free air filter, have been widely used in special vehicles, and are extensively equipped on large mining trucks and other special vehicles with ample space. However, pulse-jet air filters are usually larger and heavier than conventional air filters, which severely limits their application in special vehicles with compact layouts, such as oil exploration vehicles, military off-road vehicles, and armored vehicles. Their power compartment layouts typically employ extremely compact modular designs, making it difficult to install pulse-jet systems and safety filters. The demand from some compact power compartment models to upgrade conventional air filters to self-cleaning pulse-jet air filters is even more difficult to meet. Some models also have technical requirements such as rapid maintenance and high reliability, making the design of pulse-jet air filters under the constraints of compact space even more challenging. Summary of the Invention

[0004] In view of this, the present invention provides a compact series pulse backflush air filter equipped with a safety filter element, which can solve the problem that it is difficult to replace the self-cleaning air filter in the compact power compartment space of special vehicles. It can achieve the backflush self-cleaning function in the compact power compartment space of special vehicles, and is equipped with a safety filter element. Compared with ordinary backflush air filters on special vehicles, it has higher reliability.

[0005] The present invention adopts the following technical solution:

[0006] A compact tandem pulse backflush air filter equipped with a safety filter element includes a main filter housing, a safety filter housing, a main filter element, a safety filter element, and a backflush system;

[0007] The left end of the main filter housing is provided with a detachable inlet cover, the right end is provided with an air outlet of the main filter housing, and the lower side is provided with a dust collection hopper; the lower part of the inlet cover is provided with an air inlet pipe that communicates with the inside of the main filter housing, and the upper part is provided with a pressure relief port, which is located on the outer end face of the inlet cover and is provided with rubber.

[0008] The left end of the safety filter housing is open, the right end is provided with a safety filter housing air outlet, the upper end is provided with a removable safety filter cover plate, and the lower end is provided with a round hole. The left end of the safety filter housing is fixedly connected to the right end of the main filter housing.

[0009] The main filter element and the safety filter element are installed in the main filter element housing and the safety filter element housing respectively, and the main filter element and the safety filter element are coaxial. The round hole is located between the right end face of the main filter element and the left end face of the safety filter element.

[0010] The backflush system is detachably installed below the safety filter housing, and the air pipe in the backflush system passes through the round hole at the lower end of the safety filter housing, so that the nozzle on the air pipe is located on the central axis of the main filter and faces the main filter.

[0011] Furthermore, an inclined dust guide plate is provided on the lower side of the inner cavity of the main filter element housing to guide the dust generated during backflushing into the dust collection hopper;

[0012] The angle between the guide plate and the horizontal plane is an acute angle of 20° to 50°.

[0013] Furthermore, the air intake pipe is a bent pipe, and a guide plate is provided inside the air intake pipe to reduce the resistance of air entering the main filter housing;

[0014] The connection between the air guide plate and the dust guide plate forms a stepped structure to prevent dust from entering the air intake pipe during backflushing.

[0015] Furthermore, the length of the main filter element is 2 to 6 times the length of the safety filter element;

[0016] The depth to which the nozzle extends into the inner cavity of the main filter element is -0.2 to 0.2 times the length of the main filter element.

[0017] Furthermore, it also includes a clamping mechanism;

[0018] The clamping mechanism is disposed on the outer wall surface of the right end of the main filter element housing; the clamping mechanism is used to clamp the safety filter element to the right wall surface of the safety filter element housing.

[0019] Furthermore, the clamping mechanism includes a hinge and two pressure strips;

[0020] The two pressure strips are installed parallel to each other on the outer wall of the right end of the main filter element housing via the hinge, and the two pressure strips are symmetrical about the center of the safety filter element;

[0021] When the two pressure strips rotate around the hinge pin to a set angle, the pressure strips press against the safety filter element, which can press the safety filter element tightly against the right wall of the safety filter element housing.

[0022] Furthermore, the set angle is 90°, and it also includes a limiting plate and two safety filter cover limiting blocks;

[0023] The limiting plate is disposed on the outer wall surface of the right end of the main filter element housing, and is used to limit the maximum opening angle of the hinge to 90°.

[0024] When the opening angle of the hinges is 90°, the interval between the two pressure strips is the longest, and the longest interval is S1;

[0025] Two safety filter cover plate limiting blocks are symmetrically fixed on the safety filter cover plate, and the outer spacing between the two safety filter cover plate limiting blocks is S2; and S2 = S1;

[0026] When the hinge opens at an angle of 90°, the safety filter cover can be placed on the safety filter housing, and the safety filter cover limiting block and the limiting plate are located on both sides of the pressure strip, limiting the pressure strip in both directions, so that the hinge is kept in a 90° opening angle state; after removing the safety filter cover, the bidirectional limitation on the pressure strip can be released;

[0027] When the opening angle of the hinge is less than 90°, the safety filter cover plate limiting block interferes with the pressure strip, and the safety filter cover plate cannot be placed on the safety filter housing.

[0028] Furthermore, a handle is provided on the pressure strip;

[0029] When the hinge opens at an angle of 90°, the axis of the handle is parallel to the safety filter element.

[0030] Furthermore, the backflush system also includes an air tank, a pulse valve, and a pulse controller;

[0031] The air tube is connected to the air bag, and a pulse valve is provided on the air tube;

[0032] The pulse controller can control the pulse valve to start, causing the nozzle to spray air for backflushing.

[0033] Furthermore, the detachable connection is a snap-fit ​​connection;

[0034] The pressure relief port is provided with ribs, and the outer side of the ribs is flush with the outer side of the inlet cover.

[0035] Beneficial effects:

[0036] 1. A compact tandem pulse backflush air filter equipped with a safety filter element includes a main filter housing, a safety filter housing, a main filter element, a safety filter element, and a backflush system; the main filter housing has a removable inlet cover at its left end, an air outlet at its right end, and a dust collection hopper at its lower side; the inlet cover has an air inlet pipe communicating with the interior of the main filter housing at its lower part, and a pressure relief port at its upper part, with a rubber seal on the outer end face of the inlet cover; the safety filter housing has an open left end and an air outlet at its right end. The upper end is equipped with a removable safety filter cover, and the lower end is equipped with a round hole. The left end of the safety filter housing is fixedly connected to the right end of the main filter housing. The main filter and the safety filter are respectively installed in the main filter housing and the safety filter housing, and the main filter and the safety filter are coaxial. The round hole is located between the right end face of the main filter and the left end face of the safety filter. The backflush system is detachably installed below the safety filter housing, and the air pipe in the backflush system passes through the round hole at the lower end of the safety filter housing, so that the nozzle on the air pipe is located on the central axis of the main filter and faces the main filter.

[0037] Thus, this compact tandem pulse-jet air filter equipped with a safety filter element features a compact structure, solving the problem of limited space in the compact engine compartment of special vehicles making it difficult to install self-cleaning air filters. It achieves back-jet self-cleaning functionality within the confined space of a special vehicle's engine compartment and is equipped with a safety filter element. During forward filtration, air flows into the main filter housing from the intake pipe and passes through both the main filter and the safety filter element before exiting from the safety filter housing's outlet. During back-jet cleaning, the back-jet airflow is ejected from the nozzle and discharged through the pressure relief port, causing dust on the main filter element to fall into the dust collection hopper. Even if the main filter element is damaged, the safety filter element can still perform filtration, offering higher reliability compared to ordinary back-jet air filters used in special vehicles. Furthermore, the main filter element can be removed for inspection, maintenance, and replacement by removing the inlet cover, and the safety filter element can be removed for inspection, maintenance, and replacement by removing the safety filter element cover, making it convenient and quick.

[0038] 2. An inclined dust guide plate is installed on the lower side of the inner cavity of the main filter element housing to guide the dust generated during backflushing into the dust collection hopper; the angle between the dust guide plate and the horizontal plane is an acute angle of 20° to 50°. In this way, during backflushing, the dust falling from the main filter element is collected by the dust guide plate and deposited into the dust collection hopper for disposal when the maintenance cycle is reached.

[0039] 3. The stepped structure formed at the connection between the baffle and the dust guide plate can prevent dust falling from the main filter element during backflushing from entering the intake pipe.

[0040] 4. The length of the main filter element is 2 to 6 times the length of the safety filter element. Since the safety filter element primarily serves as a backup, making the main filter element 2 to 6 times its length reduces air resistance as it flows through the filter, ensuring filtration efficiency. This results in high efficiency, low resistance, and an extended lifespan for the air filter. The nozzle extends into the inner cavity of the main filter element to a depth of -0.2 to 0.2 times its length. This reduces blowing resistance and prevents backflow from damaging the main filter element, further extending the air filter's lifespan.

[0041] 5. The clamping mechanism is located on the outer wall of the right end of the main filter element housing; the clamping mechanism is used to press the safety filter element against the right wall of the safety filter element housing. In this way, the air blowing pipe of the backflushing system can be arranged at the interval between the right end of the main filter element and the left end of the safety filter element, making the air filter structure more compact.

[0042] 6. When the hinge opens at an angle of 90°, the safety filter cover can be placed on the safety filter housing, and the safety filter cover limiting block and the limiting plate are located on both sides of the pressure strip, limiting the pressure strip in both directions, so that the hinge is kept in a 90° opening angle state; after removing the safety filter cover, the bidirectional limitation on the pressure strip can be released; when the hinge opens at an angle of less than 90°, the safety filter cover limiting block and the pressure strip interfere with each other, and the safety filter cover cannot be placed on the safety filter housing.

[0043] Thus, the safety filter cover can only be installed after the safety filter element is compressed, providing a foolproof self-check mechanism to prevent the safety filter element from being installed out of order. Furthermore, the safety filter cover's limiting block not only limits the pressure strip but also functions as a foolproof self-check mechanism for the compressed safety filter element, avoiding the use of different structures for pressure strip limiting and foolproof self-check mechanisms, resulting in a more compact air filter structure.

[0044] 7. The detachable connection is a snap-fit ​​connection, which allows for convenient and quick disassembly. The pressure relief port is equipped with ribs, and the outer side of the ribs is flush with the outer side of the inlet cover plate. In this way, because there is negative pressure inside the main filter element housing during positive filtration, the rubber can adhere to the end face of the pressure relief port under the action of negative pressure to achieve a seal. Moreover, the ribs support the rubber, preventing the rubber from bulging into the safety filter element housing under negative pressure, thus avoiding the problem of uneven contact surface between the rubber and the end face of the pressure relief port, which would damage the sealing effect. Attached Figure Description

[0045] Figure 1The present invention provides a structural outline of a compact series pulse backflush air filter equipped with a safety core;

[0046] Figure 2 This is a cross-sectional view of a compact series pulse backflush air filter equipped with a safety core provided by the present invention;

[0047] Figure 3 This is a schematic diagram of the forward filtration operation of a compact series pulse backflush air filter equipped with a safety core, provided by the present invention.

[0048] Figure 4 This is a schematic diagram of the backflushing cleaning operation of a compact series pulse backflushing air filter equipped with a safety core, provided by the present invention.

[0049] Figure 5 This is a schematic diagram of the backflush system structure provided by the present invention. The left figure shows the outer three-dimensional structure, and the right figure shows a cross-sectional view.

[0050] Figure 6 This is a schematic diagram of the inlet cover plate structure provided by the present invention. The left diagram shows the external structure, and the right diagram shows the internal structure.

[0051] Figure 7 This is a schematic diagram of the main core shell structure provided by the present invention. The left diagram shows the structure with the ash guide plate, and the right diagram shows the structure after the ash guide plate is removed.

[0052] Figure 8 This is a schematic diagram of the safety core housing structure provided by the present invention;

[0053] Figure 9 This is a schematic diagram of the pressing mechanism structure provided by the present invention;

[0054] Figure 10 This is a schematic diagram showing the positional relationship between the clamping mechanism and the safety core housing provided by the present invention. The right figure is a side view of the left figure.

[0055] Figure 11 The left figure is a schematic diagram of the clamping mechanism provided by the present invention clamping the safety core, and the right figure is a schematic diagram of the clamping mechanism releasing the safety core.

[0056] Figure 12 These are schematic diagrams of the backflush system provided by this invention at two different angles;

[0057] Figure 13 The left figure is a structural schematic diagram of the safety core shell and the main core shell provided by the present invention, and the right figure is a structural schematic diagram of the inlet cover plate and the main core shell;

[0058] Figure 14 This is a schematic diagram of the connection between the air filter and the power compartment of a special vehicle provided by the present invention;

[0059] Figure 15 This is a schematic diagram of the structure after the safety core cover plate has been removed, as provided by the present invention, showing the safety core in a compressed state;

[0060] Figure 16 This is a schematic diagram of the structure after the safety core cover plate has been removed, as provided by the present invention. The safety core is in an uncompressed state.

[0061] Figure 17 This is a schematic diagram of the structure after the inlet cover plate has been removed, provided by the present invention;

[0062] Among them, 1-nozzle, 2-air pipe, 3-air manifold, 4-inlet valve, 5-safety valve, 6-drain bolt, 7-pulse valve, 8-quick connector, 9-pulse controller, 10-pulse valve connector, 11-inlet pipe, 12-main core support, 13-inlet cover, 14-rubber, 15-main filter element limiting ring, 16-guide plate, 17-dust guide plate, 18-dust hopper cover, 19-dust hopper, 20-main filter element housing, 21- Mounting base, 22 - Safety filter cover, 22a - Safety filter cover body, 22b - Safety filter cover limiting block, 23 - Safety filter support, 24 - Buckle, 25 - Safety filter housing, 26 - Pressure plate, 27 - Hinge, 28 - Handle, 29 - Limiting plate, 30 - Main filter element, 31 - Safety filter element, 320 - Main filter housing outlet, 321 - Safety filter housing outlet, 33 - Welding block bolt connection assembly. Detailed Implementation

[0063] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. In the description of the present invention, it should be understood that directional terms such as "front," "back," "up," "down," "left," "right," "horizontal," "vertical," "horizontal," and "top," "bottom," etc., indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. These terms are used only for the convenience of describing the present invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of the present invention. The directional terms "inner" and "outer" refer to the inner or outer contours relative to the outline of each component itself.

[0064] Reference Figures 1 to 17 A compact tandem pulse backflush air filter equipped with a safety core includes a main filter housing 20, a safety core housing 25, a main filter element 30, a safety filter element 31, and a backflush system, wherein:

[0065] The main filter housing 20 has a removable inlet cover 13 at its left end, an air outlet 320 at its right end, and a dust collection hopper 19 at its lower side. The lower part of the inlet cover 13 has an air inlet pipe 11 communicating with the interior of the main filter housing 20, and the upper part has a pressure relief port. A rubber sheet 14 is provided on the outer end face of the pressure relief port. The safety filter housing 25 has an open left end, an air outlet 321 at its right end, a removable safety filter cover 22 at its upper end, and a round hole at its lower end. The left end of body 25 is fixedly connected to the right end of main filter housing 20; main filter element 30 and safety filter element 31 are respectively installed in main filter housing 20 and safety filter housing 25, and main filter element 30 and safety filter element 31 are coaxial, with the round hole located between the right end face of main filter element 30 and the left end face of safety filter element 31; the backflush system is detachably installed below safety filter housing 25, and the air pipe 2 in the backflush system passes through the round hole at the lower end of safety filter housing 25, so that the nozzle 1 on the air pipe 2 is located on the central axis of main filter element 30 and faces main filter element 30.

[0066] In this embodiment, the backflush system further includes a pulse valve 7, a pulse controller 9, and a gas reservoir 3 for storing gas. The gas pipe 2 is connected to the gas reservoir 3, and the pulse valve 7 is installed on the gas pipe 2. The pulse controller 9 is mounted on the gas reservoir 3 and connected to the pulse valve 7 via a signal line. The pulse controller 9 can control the pulse valve 7 to activate, causing the nozzle 1 to expel gas for backflush. Specifically, the nozzle 1 is a conical detachable nozzle, and the gas pipe 2 is an L-shaped nozzle connecting pipe. Furthermore, referring to… Figure 4 and Figure 5 The backflush system also includes a pressure relief valve 5, a drain bolt 6, a quick-connect pipe 8, and a pulse valve connector 10. The quick-connect pipe 8 is a standard accessory, consisting of an outer clamp and two short pipe sections with mating sealing surfaces. The two short pipe sections of the quick-connect pipe 8 are connected to the L-shaped nozzle and the pulse valve connector 10 respectively via external welding. The internal thread of the conical detachable nozzle is threaded to the external thread of the L-shaped nozzle connecting pipe; the pulse valve connector 10 is also threaded to the pulse valve 7. The conical detachable nozzle consists of a conical diffuser, three circumferentially distributed trapezoidal support ribs, and a threaded round pipe. The cone angle of the conical diffuser is 30°–50°, and the distance from the top of the diffuser cone extending into the right end plane of the main filter element 30 is -0.2 to 0.2 times the length of the main filter element 30 (negative values ​​are the extension length). This reduces the resistance of soot blowing and prevents the backflush airflow from damaging the main filter element 30, thus extending the life of the air filter.

[0067] See Figure 3The forward filtration process is as follows: the dust-laden airflow enters the lower part of the main filter housing 20 through the intake pipe 11, then surrounds the main filter element 30 and enters the main filter element 30 for filtration. The filtered clean airflow enters the interior of the main filter element 30, then exits the main filter housing 20 from the air outlet 320, and then enters the safety filter housing 25. It then surrounds the safety filter element 31 and enters the interior of the safety filter element 31, then exits the air filter from the air outlet 321, and finally enters the engine. Because the main filter housing 20 is under negative pressure during forward filtration, the rubber seal can adhere to the end face of the pressure relief port under the action of negative pressure to achieve a seal.

[0068] See Figure 4 The backflushing cleaning process is as follows: the pulse valve controller 9 controls the pulse valve 7 to open, and the high-pressure airflow in the air tank 3 is released. After passing through the L-shaped nozzle connecting pipe, it is guided and scattered by the conical detachable nozzle 1 and impacts the inner surface of the main filter element 30, forming a cleaning force. The accumulated dust on the outside of the main filter element 30 is removed and deposited into the dust collection hopper 19 after being collected by the dust guide plate 17. When the maintenance cycle is reached, the dust can be quickly cleaned by unscrewing the dust collection hopper cover 18. In this embodiment, the upper part of the rubber sheet 14 is fixed to the inlet cover plate 13 by screws. During the backflushing cleaning process, the rubber sheet 14 is blown open by the backflushing airflow, so that the airflow can be discharged from the pressure relief port, realizing pressure relief and dust discharge. More specifically, the inlet cover plate 13 is provided with three sets of pressure relief ports on the upper side, consisting of two sets of parallelogram pressure relief ports on both sides and a rectangular pressure relief port in the middle. The pressure relief ports are distributed around the upper side of the main filter element 30.

[0069] Moreover, referencing Figure 6 Each pressure relief port is equipped with ribs (for example, the middle pressure relief port consists of four small squares arranged in a row, with three ribs forming between the four small squares), and the outer surface of the ribs is flush with the outer surface of the inlet cover plate 13. In this way, the ribs support the rubber 14, preventing the rubber 14 from bulging into the safety filter housing 25 under negative pressure, thus avoiding uneven contact between the rubber 14 and the pressure relief port end face, which would damage the sealing effect.

[0070] Thus, this compact tandem pulse-jet air filter equipped with a safety filter element has a compact structure, solving the problem of difficulty in installing self-cleaning air filters in the compact power compartment of special vehicles. It can achieve back-jet self-cleaning function in the compact power compartment of special vehicles, and is equipped with a safety filter element 31. During forward filtration, air flows into the main filter housing 20 from the air inlet pipe 11, and flows out from the air outlet of the safety filter housing 25 after passing through the two-stage filtration of the main filter element 30 and the safety filter element 31 in sequence. During back-jet cleaning, the back-jet airflow is sprayed out from the nozzle 1 and discharged from the pressure relief port, causing the dust on the main filter element 30 to fall into the dust collection hopper 19. Even if the main filter element 30 is damaged, the safety filter element 31 can still perform filtration, which has higher reliability compared with ordinary back-jet air filters on special vehicles. In addition, after removing the inlet cover 13, the main filter element 30 can be taken out for inspection, maintenance and replacement. After removing the safety filter cover 22, the safety filter element 31 can be taken out for inspection, maintenance and replacement, which is convenient and quick.

[0071] Specifically, in this embodiment, the length of the main filter element 30 is 2 to 6 times the length of the safety filter element 31. Since the safety filter element 31 mainly serves as a safety backup, making the length of the main filter element 30 2 to 6 times the length of the safety filter element 31 can reduce the resistance of air flowing through the filter while ensuring the filtration effect. This results in high efficiency, low resistance, and improved lifespan of the air filter.

[0072] Specifically, an inclined dust guide plate 17 is provided on the lower side of the inner cavity of the main filter element housing 20 to guide the dust generated during backflushing into the dust collection hopper 19; the angle between the dust guide plate 17 and the horizontal plane is an acute angle of 20° to 50°. In this way, during backflushing, the dust falling from the main filter element 30 is collected by the dust guide plate and deposited into the dust collection hopper 19 for disposal when the maintenance cycle is reached.

[0073] Furthermore, the main filter element 30 is installed inside the main filter element housing 20 via the main filter element limiting ring 15 and the main filter element support 12 that matches the outer peripheral shape of the main filter element 30; the safety filter element 31 is installed inside the safety filter element housing via the safety filter element limiting ring and the safety filter element support 23 that matches the outer peripheral shape of the safety filter element 31. Figures 2-4The cross-sectional view does not show the complete structure of the main filter element support 12 and the safety filter element support 23. In this embodiment, the air inlet pipe 11 is a bent pipe, and a guide plate 16 is provided inside the air inlet pipe 11. The guide plate 16 can reduce the resistance of air entering the main filter element housing 20. Moreover, specifically, the guide plate 16 has a triangular planar structure, one side of which is flanged with a flange height of 10-20mm. The edge of the flange is connected to the hypotenuse of the dust guide plate 17 to form a step (not shown in the figure), which is used to prevent dust from entering the air inlet pipe 11 during backflushing. Moreover, there are two dust guide plates 17, which are symmetrically arranged on both sides of the top of the dust collection hopper 19. The angle between the dust guide plate 17 and the horizontal plane is 20° to 50°. Figure 7 Below the dust guide plate 17, two symmetrical mounting bases 21 are provided. Each mounting base 21 has bolt holes. The air filter provided by this invention is fixedly connected to the crossbeam of the power compartment of the special vehicle via these mounting bases 21. Furthermore, the dust collection hopper 19 consists of two sections: the upper section is a square straight tube with a height of 10mm to 20mm, and the lower section is a tapered square tube. The bottom of the lower section has a circular outlet with a diameter of 20mm to 100mm. The bottom of the dust collection hopper 19 is provided with a threaded dust collection hopper cover 18. Unscrewing the dust collection hopper cover 18 allows for the cleaning of the dust collected in the dust collection hopper. More specifically, the backflushing system and the safety filter housing 25 are connected by a four-bolt connection group 33. Specifically, the safety filter housing 25 has welded blocks with threaded holes, and bolts are installed on the backflushing system. The bolts are threadedly connected to the threaded holes on the welded blocks. The upper surface of the air tank 3 is tightly attached to the lower surface of the safety filter housing 25, and is fixed by the pre-tightening force of the welded block bolt connection group 33.

[0074] Furthermore, the compact tandem pulse backflush air filter equipped with a safety filter element 31 also includes a pressing mechanism. This pressing mechanism is located on the outer wall of the right end of the main filter housing 20 and is used to press the safety filter element 31 against the right wall of the safety filter housing 25. This allows for the arrangement of the backflush system's air pipe 2 at a distance between the right end of the main filter element 30 and the left end of the safety filter element 31, making the air filter structure more compact. It is understood that various structures can be used to achieve this pressing function. In this embodiment, the pressing mechanism includes a hinge 27 and two pressure bars 26. The two pressure bars 26 are mounted parallel to each other on the outer wall of the right end of the main filter housing 20 via the hinge 27, and are symmetrical about the center of the safety filter element 31. When the two pressure bars 26 rotate around the hinge pin of the hinge 27 to a set angle, the pressure bars 26 press against the safety filter element 31, thereby pressing the safety filter element 31 against the right wall of the safety filter housing 25.

[0075] Specifically, in this embodiment, the angle is set to 90°, that is, when the two pressure strips 26 rotate 90° around the hinge pin of the hinge 27, the pressure strips 26 press against the safety filter element 31 to achieve the clamping of the safety filter element 31.

[0076] As an improvement, in this embodiment, the clamping mechanism further includes a limiting plate 29 and two safety filter cover limiting blocks 22b. The limiting plate 29 is disposed on the outer wall surface of the right end of the main filter housing 20 to limit the maximum opening angle of the hinge 27 to 90°. Moreover, when the opening angle of the hinge 27 is 90°, the interval between the two pressure strips 26 is the longest, and the longest interval is S1. The two safety filter cover limiting blocks 22b are symmetrically fixed on the safety filter cover body 22a of the safety core cover 22, and the outer interval of the two safety filter cover limiting blocks 22b is S2, and S2 = S1. When the opening angle of the hinge 27 is 90°, the safety filter cover 22 can cover the safety filter housing. On the body 25, the safety filter cover limiting block 22b and the limiting plate 29 are located on both sides of the pressure strip 26, limiting the pressure strip 26 in both directions, keeping the hinge 27 in a 90° opening angle state. After removing the safety filter cover 22, the bidirectional limitation on the pressure strip 26 can be released. When the opening angle of the hinge 27 is less than 90°, the safety filter cover limiting block 22b interferes with the pressure strip 26, and the safety filter cover 22 cannot be placed on the safety filter housing 25. Thus, the safety filter cover 22 can only be installed after the safety filter 31 is pressed tight, which has a foolproof self-check mechanism for the pressed state of the safety filter 31 and can also prevent the safety filter 31 from being missed. Furthermore, the safety filter cover plate limiting block 22b on the safety filter cover plate 22 not only limits the pressure strip 26, but also serves as a foolproof self-checking mechanism for the pressed state of the safety filter 31. This avoids using different structures for limiting the pressure strip 26 and for the foolproof self-checking of the air filter, making the air filter structure more compact. In this embodiment, the pressure strip 26 is equipped with a handle 28. When the opening angle of the hinge 27 is 90°, the axis of the handle 28 is parallel to the safety filter 31. This makes it easier to determine whether the safety filter 31 is properly pressed.

[0077] More specifically, refer to Figures 9-11 Each pressure bar 26 is equipped with two hinges 27, one pressure bar 26, one handle 28, and two limiting plates 29. One page of each of the two hinges 27 is rigidly installed on one side of the pressure bar 26, one above the other. The handle 28 is rigidly connected to the top of the other side of the pressure bar 26. The other page of each of the two hinges 27 is installed on the end face of the air outlet 320 of the main core housing. The two limiting plates 29 are welded to the main core housing 20, limiting the maximum opening angle of the hinges 27 to 90°. The pressure bar 26 and the handle 29 can rotate along the hinge axis. The minimum angle between the axis of the pressure bar 26 and the handle 29 and the outlet end face of the main core housing 20 is 0° to 15°, which is the relaxed state of the pressing mechanism. Due to the movement restriction of the limiting plates 29, the maximum angle between the axis of the handle 28 and the outlet end face of the main core housing 20 is 90°, which is the pressed state of the pressing mechanism.

[0078] Moreover, in this embodiment, the pressure strip 26 has an L-shaped steel plate in cross section. The height of the L-shaped steel plate is 1 to 1.4 times the diameter of the safety core 31. The short side of the L-shaped steel plate has smooth rounded corners and flanges. The long side of the L-shaped steel plate has three square weight-reducing holes, which are located above the hinge 27 mounting location, in the middle of the two hinge 27 mounting locations, and below the hinge 27 mounting location, respectively. The safety filter cover plate limiting blocks 22b are symmetrically distributed about the center plane of the safety filter housing 25. After the safety filter cover plate 22 is installed in place, the safety filter cover plate limiting blocks 22b can completely restrict the pressure plate 26 from rotating in a direction less than 90°. At 90°, the distance between the inner sides of the L-shaped long sides of the two pressure strips 26 is equal to the distance between the outer sides of the two safety filter cover plate limiting blocks 22b + 2 to 6 mm, where 2 to 6 mm is taken into account for processing errors. After final installation, the distance between the inner sides of the L-shaped long sides of the two pressure strips 26 is exactly equal to the distance between the outer sides of the two safety filter cover plate limiting blocks 22b. Thus, the safety filter cover plate 22 can only be successfully installed when the pressure strip 26 rotates 90° around the hinge axis. The safety filter cover plate limiting blocks 22b and the limiting plate 29 together constitute the bidirectional limiting mechanism and the self-checking mechanism for preventing mistake in the pressing state of the safety filter 31 pressing mechanism.

[0079] In addition, in this embodiment, the detachable connection is a snap-fit ​​connection. Specifically, the inlet cover plate 13 is snap-fitted to the main filter element housing 30 via snap-fit ​​24. The main filter element housing 20 has a 10mm flange on its assembly surface for installing the sealing rubber 14. After the snap-fit ​​24 is tightened, a good seal is achieved. The main filter element housing 20 is sealed and welded to the safety filter element housing 31. The circumference of the air outlet end face of the main filter element housing 20 has a 3mm flange, which is slightly larger than the circumference of the safety filter element housing 25, enabling quick positioning of the main filter element housing 20 and the safety filter element housing 25 during welding. The safety filter element cover plate 22 is snap-fitted to the safety filter element housing 25 via snap-fit ​​24. There is a sealing gasket between the contact surfaces of the safety filter element cover plate 22 and the main filter element housing 25. The safety filter element cover plate 22 is pressed tightly downward onto the sealing surface via snap-fit ​​24, achieving a seal inside the safety filter element housing 25.

[0080] See also Figure 15 and Figure 16 The maintenance and inspection method for safety filter element 31 is as follows: remove the safety filter element cover 22, then fold the handle 28 inwards, and then pull the safety filter element 31 upwards for inspection or replacement. See also... Figure 17 The maintenance method for the main filter element 30 is to remove the inlet cover plate 13, and then simply drag the rear end of the main filter element 30 to remove it for inspection or replacement.

[0081] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A compact tandem pulse backflush air filter equipped with a safety filter element, characterized in that, Includes main filter housing, safety filter housing, main filter, safety filter, and backflush system; The left end of the main filter housing is provided with a detachable inlet cover, the right end is provided with an air outlet of the main filter housing, and the lower side is provided with a dust collection hopper; the lower part of the inlet cover is provided with an air inlet pipe that communicates with the inside of the main filter housing, and the upper part is provided with a pressure relief port, which is located on the outer end face of the inlet cover and is provided with rubber. The left end of the safety filter housing is open, the right end is provided with a safety filter housing air outlet, the upper end is provided with a removable safety filter cover plate, and the lower end is provided with a round hole. The left end of the safety filter housing is fixedly connected to the right end of the main filter housing. The main filter element and the safety filter element are installed in the main filter element housing and the safety filter element housing respectively, and the main filter element and the safety filter element are coaxial. The round hole is located between the right end face of the main filter element and the left end face of the safety filter element. The backflush system is detachably installed below the safety filter housing, and the air pipe in the backflush system passes through the round hole at the lower end of the safety filter housing, so that the nozzle on the air pipe is located on the central axis of the main filter and faces the main filter. An inclined dust guide plate is provided on the lower side of the inner cavity of the main filter element housing to guide the dust generated during backflushing into the dust collection hopper; the angle between the dust guide plate and the horizontal plane is an acute angle of 20° to 50°. The air intake pipe is a bent pipe, and a guide plate is provided inside the air intake pipe to reduce the resistance of air entering the main filter housing; the connection between the guide plate and the dust guide plate forms a stepped structure to prevent dust from entering the air intake pipe during backflushing. It also includes a pressing mechanism; the pressing mechanism is disposed on the outer wall surface of the right end of the main filter element housing; the pressing mechanism is used to press the safety filter element against the right wall surface of the safety filter element housing; The pressing mechanism includes a hinge and two pressure strips. The two pressure strips are installed parallel to each other on the outer wall of the right end of the main filter element housing through the hinge. The two pressure strips are symmetrical about the center of the safety filter element. When the two pressure strips rotate 90° around the hinge pin, the pressure strips press against the safety filter element, which can press the safety filter element tightly against the right wall of the safety filter element housing. It also includes a limiting plate and two safety filter cover limiting blocks. The limiting plate is set on the outer wall surface of the right end of the main filter housing and is used to limit the maximum opening angle of the hinge to 90°. When the hinge opening angle is 90°, the interval between the two pressure strips is the longest, and the longest interval is S1. The two safety filter cover plate limiting blocks are symmetrically fixed on the safety filter cover plate, and the outer interval of the two safety filter cover plate limiting blocks is S2, and S2=S1. The safety filter cover plate can cover the safety filter housing, and the safety filter cover plate limiting blocks and the limiting plate are located on both sides of the pressure strip, limiting the pressure strip in both directions, so that the hinge is kept in a 90° opening angle state; after removing the safety filter cover plate, the bidirectional limitation on the pressure strip can be released. When the opening angle of the hinge is less than 90°, the safety filter cover plate limiting block interferes with the pressure strip, and the safety filter cover plate cannot be placed on the safety filter housing.

2. A compact series pulse backflush air filter equipped with a safety filter element according to claim 1, characterized in that, The length of the main filter element is 2 to 6 times the length of the safety filter element; The depth to which the nozzle extends into the inner cavity of the main filter element is -0.2 to 0.2 times the length of the main filter element.

3. A compact series pulse backflush air filter equipped with a safety filter element according to claim 1, characterized in that, The pressure bar is provided with a handle; When the hinge opens at an angle of 90°, the axis of the handle is parallel to the safety filter element.

4. A compact series pulse backflush air filter equipped with a safety filter element according to any one of claims 1 to 3, characterized in that, The backflush system also includes an air tank, a pulse valve, and a pulse controller; The air tube is connected to the air bag, and a pulse valve is provided on the air tube; The pulse controller can control the pulse valve to start, causing the nozzle to spray air for backflushing.

5. A compact series pulse backflush air filter equipped with a safety filter element according to any one of claims 1 to 3, characterized in that, The detachable connection is a snap-fit ​​connection; The pressure relief port is provided with ribs, and the outer side of the ribs is flush with the outer side of the inlet cover.

Images