A combined filtering device for a gas purification system

Abstract

The present invention proposes a combined filtering device for a gas purification system, including a directional valve, a gas transmission channel is arranged in the lower shell of the directional valve, and an air inlet I, an air outlet I and a return port are arranged on the gas transmission channel, the air outlet I is connected to the main filter, and a push assembly is arranged in the return port. The upper end of the lower shell is screwed with the upper shell, and a sliding valve stem and an air outlet II are arranged in the upper shell. A bypass valve is also arranged in the upper shell, and the air outlet II and the air inlet I are connected through the bypass valve, and the air outlet II is connected to the main filter through the first filter. The air outlet end of the main filter is provided with a blocking assembly, and the left side of the upper shell is provided with an air outlet III. A blocking block is fixed to the lower part of the valve stem. When the valve stem drives the blocking block to move downward, the air outlet III is communicated with the air outlet I, and the air outlet III is connected to the return port through the second filter. The present invention realizes the backwashing of the main filter without suspending the gas transmission and adopting a solenoid valve, etc., which is safer.

Description

Technical Field

[0001] The invention relates to the technical field of filtering equipment, in particular to a combined filtering device for a gas purification system. Background Art

[0002] Before using the gas, it is necessary to filter and purify it to remove particulate impurities mixed in the gas. The existing filter usually includes a filter shell with a filter element fixed inside the filter shell. In order to avoid gas leakage, the filter shell is usually a non-detachable structure. For example, the filter shell includes a middle shell and two end covers. After the filter element is fixed to one end cover, the two end covers are directly welded and fixed to the middle shell. That is, if the filter is blocked, the entire filter needs to be removed from the gas pipeline for cleaning, which is time-consuming and labor-intensive, and requires the gas delivery to be suspended.

[0003] In the prior art, a recoil mechanism is often used to clean the filter online. However, the recoil mechanism often requires additional equipment such as a recoil pump, and the gas delivery also needs to be suspended. Patent document CN206063981U discloses a gas filter device that can be repaired online, including two filter cartridges. When one filter cartridge is blocked, the other filter cartridge can be made to work by switching the gas delivery route, so that the gas company can disassemble and clean the blocked filter cartridge. The device has the following problems: on the one hand, it cannot realize automatic cleaning of the filter cartridge, and on the other hand, the adjustment of the delivery route mainly relies on electrical equipment such as solenoid valves and differential pressure gauges, which need to be well insulated to avoid the danger of leakage, and it cannot be used in an environment where electricity is restricted or inconvenient.

[0004] Patent document CN106731121A discloses a lubricating filter element that can be switched online. Using the power of the filtered lubricating oil, two filter elements can be switched online for filtering and backwashing. If this filter element structure is used for gas filtration and purification, the following problems are likely to occur: the gas after backwashing needs to be prepared in a backwashing collection box, and cannot be directly filtered and recovered online; to achieve automatic cleaning of the filter element, it mainly relies on switching and adjusting the gas delivery route of the solenoid valve, etc., and how to achieve automatic online cleaning of the filter element without using electricity and adding additional drive devices, and without the need for temporary gas delivery, is not involved. Summary of the invention

[0005] The present invention proposes a combined filtering device for a gas purification system, which realizes automatic adjustment of the gas transmission path by cooperating with the power of gas transmission through a regulating valve, and then realizes backwashing of the main filter through the cooperation of a first filter, a main filter and a second filter. The whole process does not require suspending gas transmission, nor does it require the use of electrical components such as solenoid valves, thereby saving costs and being safer.

[0006] The technical solution of the present invention is implemented as follows: a combined filtering device for a gas purification system, comprising a main filter, a first filter, a second filter and a directional control valve, the directional control valve comprising a lower shell, a gas transmission channel is arranged in the lower shell, an air inlet I is arranged at the right end of the gas transmission channel, an air outlet I is arranged at the left end, the air outlet I is connected to the air inlet end of the main filter, a return port is arranged at the lower end of the gas transmission channel, a top moving component is arranged in the return port, an upper shell is screwed to the upper end of the lower shell, a vertical slide groove is arranged in the upper shell, and a sliding The valve stem is coaxially arranged with the push-moving assembly, an air outlet II is arranged on the upper part of the vertical slide groove, a bypass valve is also arranged in the upper shell body, the air outlet II is connected with the air inlet I through the bypass valve, the air outlet II is connected with the air outlet end of the main filter through the first filter, the air outlet end of the main filter is provided with a blocking assembly, the left side of the upper shell body is provided with an air outlet III, a blocking block is fixed to the lower part of the left side of the valve stem, when the valve stem drives the blocking block to move downward, the air outlet III is communicated with the air outlet I, and the air outlet III is connected with the return port through the second filter.

[0007] Furthermore, the upper part of the vertical slide is an air collecting groove, the inner diameter of the air collecting groove is larger than the vertical slide, the air outlet II is connected to the air collecting groove, and the air collecting groove is connected to the air inlet I through the bypass valve; the upper end of the valve stem is placed in the air collecting groove, and a push plate is fixed thereto, a compression spring is provided on the upper side of the push plate, a limit groove is provided at the position of the valve stem corresponding to the bypass valve, the bypass valve is connected to the limit block, and the limit block is driven to move out of or insert into the limit groove by opening and closing the bypass valve. Through the cooperation of the bypass valve and the limit block, the bypass valve is opened, the limit block moves out of the limit groove, the limit on the valve stem is released, the bypass valve is closed, and the limit block is inserted into the limit groove to limit the position of the valve stem.

[0008] Furthermore, the upper shell is provided with an air inlet II, a horizontal groove and an upper channel connected in sequence, the air inlet II is connected to the air inlet I, the outlet of the upper channel corresponds to the position of the push plate, the push plate moves down, the upper channel is connected to the gas collecting groove, the push plate moves up and resets, and the outlet of the upper channel is closed; the bypass valve is placed in the horizontal groove, the bypass valve includes a piston, the right end of the piston is provided with a first supporting spring, the air inlet II is located on the left side of the piston, the upper channel is located on the right side of the piston, and the upper channel is closed and opened by the left and right movement of the piston. When the main filter is blocked, the gas enters the horizontal groove through the air inlet II and pushes the piston to move right, and the bypass valve opens.

[0009] Furthermore, the limit block is connected to the left end of the piston through a connecting rod, the outer diameter of the connecting rod is smaller than the inner diameter of the horizontal groove, and the air inlet II corresponds to the position of the connecting rod.

[0010] Furthermore, a sliding hole is provided between the return port and the gas transmission channel, and the push assembly includes a vertically sliding push rod, the upper end of the push rod extends out of the sliding hole and is placed in the gas transmission channel; the lower end of the push rod passes through the second support spring and is fixed with a sealing push block, and an axial through hole is provided in the push rod and the sealing push block. After the valve stem moves down, the valve stem and the top seal of the axial through hole are abutted, and the outer diameter of the push rod is smaller than the valve stem. After the push rod moves up, the gas transmission channel is opened; an air outlet hole is provided on the push rod in the sliding hole, and the air outlet hole is connected to the axial through hole, and the inner diameter of the air outlet hole is smaller than the axial through hole. After the push rod moves up, air is released through the air outlet hole to reduce the amount of gas in the return port, which is convenient for the push rod to move down and reset. The inner diameter of the air outlet hole is smaller than the axial through hole, and the amount of air released from the air outlet hole is small, which does not affect the upward movement of the push rod.

[0011] Furthermore, a valve plate is fixed in the return port, the valve plate abuts against the lower end of the sealing push block, the middle of the valve plate is used to close the axial through hole, and a connecting hole is arranged around the valve plate, the inner diameter of the connecting hole is larger than the axial through hole. The valve plate and the axial through hole constitute a one-way valve structure to prevent the gas from entering the return port in reverse.

[0012] Furthermore, the blocking component is a hollow elastic ball, which is connected to the air outlet of the first filter. After the elastic ball is inflated, it blocks the air outlet of the main filter. After the elastic ball is deflated and contracted, the air outlet of the main filter opens. A one-way valve facing the main filter is provided on the elastic ball.

[0013] Furthermore, the first filter and the second filter both include a shell, a detachable end cap is provided at one end of the shell, an air inlet port is provided on the side wall of the shell, an air outlet connector is fixed at the other end of the shell, a second filter cartridge is provided in the shell, the air outlet end of the second filter cartridge is sealed and sleeved on the air outlet connector, and a compressed spring is provided between the sealing end of the second filter cartridge and the end cap. This structural arrangement makes it easy to disassemble the second filter cartridge for cleaning or replacement.

[0014] Furthermore, the main filter includes a filter shell, the left end of the filter shell is an air outlet end, and the right end is an air inlet end. A first filter cartridge is arranged in the filter shell, the left end of the first filter cartridge is fixedly connected to the air outlet end of the filter shell, and the right end of the first filter cartridge is a closed end. The filter cartridge includes a fine filter cartridge, and a coarse filter cartridge is mounted on the outer side of the fine filter cartridge.

[0015] Beneficial effects of the present invention:

[0016] After the main filter of the combined filter device of the present invention is clogged, the regulating valve cooperates with the power of gas transmission to realize automatic adjustment of the gas transmission path, and then the filtered gas is used to backwash the main filter through the cooperation of the first filter, the main filter and the second filter. The backwashed gas is filtered and returned to the main filter for normal transmission. There is no need to use electrical devices such as solenoid valves and sensors, which saves costs and is safer. When the first filter and the second filter cartridge of the second filter are subsequently disassembled and cleaned, the operation of the main filter is not affected, and there is no need to suspend gas transmission.

[0017] The directional control valve of the present invention cooperates with the bypass valve and the valve stem. If the main filter is blocked, the pressure at the air inlet I increases, and the bypass valve is automatically opened to connect the air inlet I with the air outlet II. At the same time, the bypass valve drives the limit block away from the limit groove, releases the limit on the valve stem, and moves the valve stem downward to close the gas transmission channel, thereby connecting the air outlet I with the air outlet III. After the gas enters the first filter through the air inlet I and the air outlet II for filtration, the main filter is backwashed, and the blocking component is used to control the opening and closing of the air outlet end of the main filter, so that the gas filtered by the first filter flows to the main filter; the gas after backwashing flows into the second filter through the air outlet I and the air outlet III for filtration, and enters the return port after filtration, and the valve stem is pushed upward and reset by the jacking component to open the gas transmission channel, so that the gas transmission channel and the main filter resume work.

[0018] The blocking component of the present invention has a simple structure. The gas filtered by the first filter first enters the elastic ball, thereby inflating the elastic ball and blocking the gas outlet of the main filter. Then, gas is inflated into the main filter through the one-way valve to achieve backwashing of the main filter. After the subsequent gas transmission channel is opened, the gas outlet II and the gas outlet III are closed. As the gas is transported, the pressure of the forward flow of the main filter increases, causing the elastic ball to be squeezed, deflated and contracted, and the gas outlet of the main filter is opened. At the same time, the contracted elastic ball can also prevent the gas from reversely entering the first filter.

[0019] The push-moving assembly of the present invention cooperates with the axial through hole and the air outlet hole. After the push rod pushes the valve stem to move up and reset, the gas in the return port no longer increases. As the air outlet hole is deflated, the pressure in the return port decreases, the push rod moves downward, and the axial through hole opens, making it easy for the gas in the return port to return to the main filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a structural schematic diagram of the present invention;

[0022] Figure 2 is a schematic diagram of the structure of the main filter;

[0023] Figure 3 is a schematic diagram of the structure of the first filter;

[0024] Figure 4 It is a structural schematic diagram of the directional control valve;

[0025] Figure 5 for Figure 4 A partial enlarged view of middle A;

[0026] Figure 6 for Figure 4 A partial enlarged view of B in the middle;

[0027] Figure 7 It is a structural schematic diagram of the elastic ball in the contracted state;

[0028] Figure 8 Schematic diagram of the structure of an elastic ball in an expanded state.

[0029] Main filter 1, first filter 2, second filter 3, regulating valve 4, filter shell 5, first filter cartridge 6, outer shell 7, end cover 8, second filter cartridge 9, lower shell 10, gas transmission channel 11, air inlet I12, air outlet I13, return port 14, air outlet 15, push rod 16, second supporting spring 17, sealing push block 18, axial through hole 19, valve plate 20, upper shell 21, valve stem 22, air collecting groove 23, push plate 24, compression spring 25, air outlet II26, elastic ball 27, one-way valve 28, blocking block 29, air outlet III30, air inlet II31, horizontal groove 32, upper channel 33, piston 34, first supporting spring 35, limit block 36, connecting rod 37, limit groove 38, sliding hole 39, connecting hole 40. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] like Figure 1 and 2As shown, a combined filter device for a gas purification system includes a main filter 1, a first filter 2, a second filter 3 and a directional control valve 4. The main filter 1 includes a filter shell 5, the left end of the filter shell 5 is an air outlet end, and the right end is an air inlet end. A coaxial first filter cartridge 6 is arranged in the filter shell 5. The middle shell of the filter shell 5 is welded and fixedly connected to the left and right ports, and the first filter cartridge 6 cannot be removed. The right end of the first filter cartridge 6 is a closed end, and an air outlet interface is fixed on the left end, and the air outlet interface is connected to the air outlet end of the filter shell 5. The first filter cartridge 6 includes a fine filter cartridge, and a coarse filter cartridge is mounted on the outside of the fine filter cartridge.

[0032] like Figure 3 As shown, the first filter 2 and the second filter 3 both include a shell 7, one end of the shell 7 is detachably connected to an end cover 8 by bolts, an air inlet port is provided on the side wall of the shell 7, an air outlet connector is fixed to the other end of the shell 7, a second filter cartridge 9 is provided in the shell 7, the air outlet end of the second filter cartridge 9 is sealingly sleeved on the air outlet connector, and a compressed spring is provided between the sealing end of the second filter cartridge 9 and the end cover 8.

[0033] like Figure 4 and 5 As shown, the regulating valve 4 includes a lower shell 10, in which an air delivery channel 11 is arranged, an air inlet I12 is arranged at the right end of the air delivery channel 11, and an air outlet I13 is arranged at the left end, the air outlet I13 is connected to the air inlet end of the main filter 1, and a return port 14 is arranged at the lower end of the air delivery channel 11, and a vertically sliding jacking assembly is arranged in the return port 14. A sliding hole 39 is provided at the junction of the return port 14 and the gas transmission channel 11, and the inner diameter of the return port 14 is larger than the inner diameter of the sliding hole. The push assembly includes a vertically sliding push rod 16, the upper end of the push rod 16 extends out of the sliding hole 39 and is placed in the gas transmission channel 11, the lower end of the push rod 16 passes through the second support spring 17, and is fixed with a sealing push block 18, the sealing push block 18 slides along the inner wall of the return port 14 in a sealing manner, the outer diameter of the sealing push block 18 is larger than the outer diameter of the push rod 16, an axial through hole 19 is provided in the push rod 16 and the sealing push block 18, a valve plate 20 is also fixed in the return port 14, the valve plate 20 abuts against the lower end of the sealing push block 18, the middle part of the valve plate 20 is used to close the axial through hole 19, and a connecting hole 40 is provided around the valve plate 20, the connecting hole 40 is used to connect the upper and lower spaces of the valve plate 20, and the inner diameter of the connecting hole 40 is larger than the inner diameter of the axial through hole 19. The push rod 16 in the sliding hole 39 is provided with an air outlet 15, which is located on the left side of the push rod 16, and the air outlet 15 is connected to the axial through hole 19, and the inner diameter of the air outlet 15 is smaller than the axial through hole 19. The outer diameter of the push rod 16 is smaller than the valve stem 22, and after the push rod 16 moves up, the gas delivery channel 11 is opened.

[0034] like Figure 4 and 6As shown, the upper end of the lower shell 10 is screwed with the upper shell 21, and a vertical slide groove is arranged in the upper shell 21, and a sliding valve stem 22 is arranged in the vertical slide groove, and a sealing buffer pad is fixed to the lower end of the valve stem 22, and the valve stem 22 and the push rod 16 are arranged coaxially. After the valve stem 22 moves downward, the valve stem 22 and the top seal of the axial through hole 19 are abutted, and a coaxial air collecting groove 23 is provided at the upper end of the vertical slide groove. The inner diameter of the air collecting groove 23 is larger than the vertical slide groove. The upper end of the valve stem 22 is placed in the air collecting groove 23 and a push plate 24 is fixed thereto. A compression spring 25 is arranged on the upper side of the push plate 24. A limiting groove 38 is arranged at the position of the valve stem 22 corresponding to the bypass valve. The bypass valve is connected to the limiting block 36. The opening and closing of the bypass valve drives the limiting block 36 to move out of or insert into the limiting groove 38. An outlet II26 is provided at the gas collecting tank 23, and a bypass valve is also provided in the upper shell 21. The gas collecting tank 23 and the gas inlet I12 are connected through the bypass valve. When the bypass valve is opened, the gas collecting tank 23 and the gas inlet I12 are connected, and the gas enters the gas collecting tank 23 and is discharged through the outlet II26.

[0035] like Figure 1 and 4 As shown, an air outlet III30 is provided on the left side of the upper shell 21, and a blocking block 29 is fixed to the lower part of the left side of the valve stem 22. The blocking block 29 is used to block the inner end of the air outlet III30. The valve stem 22 drives the blocking block 29 to move downward into the gas transmission channel 11. The air outlet III30 is communicated with the air outlet I13, and the air outlet III30 is connected to the return port 14 through the second filter 3.

[0036] like Figure 4 and 6 As shown, the upper shell 21 is provided with an air inlet II31, a horizontal groove 32 and an upper channel 33 which are connected in sequence. The air inlet II31 is communicated with the air inlet I12. The outlet of the upper channel 33 corresponds to the position of the push plate 24. The push plate 24 moves downward to expose the outlet of the upper channel 33. The upper channel 33 is communicated with the air collecting groove 23. If the push plate 24 moves upward and resets, the outlet of the upper channel 33 is closed, and the upper channel 33 is disconnected from the air collecting groove 23. The bypass valve is placed in the horizontal groove 32. The bypass valve includes a piston 34 and a first supporting spring 35 which are connected in sequence from left to right. The air inlet II31 is located on the left side of the piston 34, and the upper channel 33 is located on the right side of the piston 34. The upper channel 33 and the air inlet II31 are communicated or disconnected by moving the piston 34 left and right.

[0037] The limit block 36 is connected to the left end of the piston 34 through a connecting rod 37. The outer diameter of the connecting rod 37 is smaller than the inner diameter of the horizontal groove 32. The position of the air inlet II31 corresponds to that of the connecting rod 37. The shape of the limit block 36 matches that of the limit groove 38. The upper and lower sides of the right end of the limit groove 38 are both inclined surfaces, which facilitates the insertion of the limit block 36 into the limit groove 38.

[0038] The filter cartridge of the main filter 1 is clogged, and the gas enters the horizontal groove 32 through the air inlet II31, and pushes the piston 34 to move right, the first support spring 35 is compressed, and the upper channel 33 and the air inlet II31 are connected; the piston 34 moves right, and at the same time drives the limit block 36 to disengage from the limit groove 38 through the connecting rod 37, and the valve stem 22 moves downward under its own gravity and the compression spring 25, and the outlet of the upper channel 33 is opened; the gas enters the gas collecting groove 23 through the upper channel 33, and then enters the first filter 2 through the air outlet II26.

[0039] like Figure 1 , 4 As shown in Figures 7 and 8, the air outlet II26 is connected to the air outlet end of the main filter 1 through the first filter 2. The air outlet end of the main filter 1 is provided with a blocking component, which is a hollow elastic ball 27. The elastic ball 27 is communicated with the air outlet end of the first filter 2. After the elastic ball 27 is inflated, it blocks the air outlet end of the main filter 1. After the elastic ball 27 is deflated and contracted, the air outlet end of the main filter 1 is opened. The elastic ball 27 is provided with a one-way valve 28 facing the main filter 1.

[0040] The method for using the combined filtering device comprises the following steps:

[0041] (1) The filter cartridge of the main filter 1 is clogged, the pressure at the air inlet I12 increases, and the bypass valve is pushed to open. The gas enters the gas collecting tank 23 through the bypass valve, and enters the first filter 2 through the air outlet II26 for filtration. At the same time, the valve stem 22 moves down to close the gas transmission channel 11. After the valve stem 22 moves down, the blocking block 29 moves away from the air outlet III30, and the air outlet III30 is connected to the air outlet I13;

[0042] (2) After being filtered by the first filter 2, the gas enters the elastic ball 27, which expands and blocks the gas outlet of the main filter 1. The gas in the elastic ball 27 back-flushes the filter cartridge of the main filter 1 through the one-way valve 28, and then enters the second filter 3 through the gas inlet end, gas outlet I13, and gas outlet III30 of the main filter 1 for filtration;

[0043] (3) After being filtered by the second filter 3, the gas enters the return port 14 and pushes the push assembly upward. The push assembly pushes the valve stem 22 upward and resets. The gas transmission channel 11 opens, and the gas outlet II 26 and the gas outlet III 30 are closed. As the gas is transported, the pressure in the main filter 1 increases, the elastic ball 27 is squeezed and shrunk, and the gas outlet end of the main filter 1 opens.

[0044] In step (1), the bypass valve opens, driving the limit block 36 to disengage from the limit groove 38. The compression spring 25 stretches and the valve stem 22 moves downward under its own weight, abutting against the upper end of the push rod 16, thereby closing the upper end of the axial through hole 19.

[0045] In step (3), after the gas enters the return port 14, the pressure in the return port 14 increases and pushes the push rod 16 upward, the second support spring 17 is compressed, and the sealing push block 18 moves away from the valve plate 20. Since the outer diameter of the push rod 16 is smaller than the valve stem 22, the push rod 16 pushes the valve stem 22 upward to reset, the gas supply channel 11 is opened, the push plate 24 closes the outlet of the upper channel 33, and the blocking block 29 closes the gas outlet III30. The first filter 2 and the second filter 3 are no longer fed with gas. As the gas continues to be delivered, the pressure in the main filter 1 increases, the squeezing elastic ball 28 contracts, the gas outlet end of the main filter 1 opens, the pressure at the gas inlet II31 decreases, the first support spring 35 extends, the piston 34 moves left to close the upper channel 33, and at the same time drives the limit block 36 to insert into the limit groove 38 to position the valve stem 22.

[0046] After the push rod 16 moves up, the gas outlet 15 is placed in the gas transmission channel 11. Since the inner diameter of the connecting hole 40 is larger than the inner diameter of the axial through hole 19, and the inner diameter of the gas outlet 15 is smaller than the axial through hole 19, the gas in the return port 14 is mainly used to push the push rod 16 to move up, so that the push rod 16 moves the valve stem 22 up and resets. Since the inner diameter of the gas outlet 15 is small and the amount of deflation is small, the push rod 16 will not move down before the valve stem 22 is positioned. After the valve stem 22 moves up and resets, the gas in the return port 14 no longer increases because the gas outlet III30 is closed. As the gas outlet 15 is deflated, the pressure in the return port 14 decreases. Under the action of the push rod 16's own weight and the second support spring 17, the push rod 16 moves down, and the upper end of the axial through hole 19 opens, further deflation is performed, so that the gas in the return port 14 returns to the gas transmission channel 11 until the push rod 16 is reset, and the valve plate 20 blocks the axial through hole 19 to prevent the gas from flowing back into the return port 14.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A combined filtering device for a gas purification system, comprising a main filter, a first filter, a second filter and a directional control valve, characterized in that: The directional control valve comprises a lower shell, in which an air transmission channel is arranged, an air inlet I is arranged at the right end of the air transmission channel, an air outlet I is arranged at the left end, the air outlet I is connected with the air inlet end of the main filter, a return port is arranged at the lower end of the air transmission channel, a top moving assembly is arranged in the return port, an upper shell is screwed on the upper end of the lower shell, a vertical slide groove is arranged in the upper shell, a sliding valve stem is arranged in the vertical slide groove, the valve stem and the top moving assembly are arranged coaxially, an air outlet II is arranged on the upper part of the vertical slide groove, a bypass valve is also arranged in the upper shell, the air outlet II and the air inlet I are connected through the bypass valve, the air outlet II is connected with the air outlet end of the main filter through the first filter, the air outlet end of the main filter is provided with a blocking assembly, an air outlet III is arranged on the left side of the upper shell, a blocking block is fixed on the lower part of the left side of the valve stem, when the valve stem drives the blocking block to move downward, the air outlet III is communicated with the air outlet I, and the air outlet III is connected with the return port through the second filter; The upper part of the vertical slide is an air collecting groove, the inner diameter of which is larger than that of the vertical slide, the air outlet II is connected to the air collecting groove, and the air collecting groove is connected to the air inlet I through the bypass valve; the upper end of the valve stem is placed in the air collecting groove, and a push plate is fixed thereto, a compression spring is arranged on the upper side of the push plate, a limit groove is arranged at the position of the valve stem corresponding to the bypass valve, the bypass valve is connected to the limit block, and the limit block is driven to move out of or insert into the limit groove by opening and closing the bypass valve; The upper shell is provided with an air inlet II, a horizontal groove and an upper channel connected in sequence, the air inlet II is communicated with the air inlet I, the outlet of the upper channel corresponds to the position of the push plate, the push plate moves downward, the upper channel is communicated with the air collecting groove, the push plate moves upward and resets, and the outlet of the upper channel is closed; the bypass valve is placed in the horizontal groove, the bypass valve includes a piston, the right end of the piston is provided with a first supporting spring, the air inlet II is located on the left side of the piston, and the upper channel is located on the right side of the piston, and the upper channel is closed and opened by moving the piston left and right; The blocking component is a hollow elastic ball, which is connected to the air outlet of the first filter. After the elastic ball is inflated, it blocks the air outlet of the main filter. After the elastic ball is deflated and contracted, the air outlet of the main filter is opened. A one-way valve toward the main filter is arranged on the elastic ball. After being filtered by the second filter, the gas enters the return port and pushes the push-moving assembly upward, and the push-moving assembly pushes the valve stem upward to reset, the gas transmission channel is opened, and the gas outlets II and III are closed.

2. A combined filtering device for a gas purification system according to claim 1, characterized in that: The limit block is connected to the left end of the piston through a connecting rod, the outer diameter of the connecting rod is smaller than the inner diameter of the horizontal groove, and the air inlet II corresponds to the position of the connecting rod.

3. A combined filtering device for a gas purification system according to claim 1 or 2, characterized in that: A sliding hole is provided between the return port and the gas transmission channel, and the push assembly includes a vertically sliding push rod, the upper end of the push rod extends out of the sliding hole and is placed in the gas transmission channel; the lower end of the push rod passes through the second supporting spring and is fixed with a sealing push block, an axial through hole is provided in the push rod and the sealing push block, after the valve stem moves downward, the valve stem and the top seal of the axial through hole abut against each other, the outer diameter of the push rod is smaller than the valve stem, and after the push rod moves upward and resets, the gas transmission channel is opened; an air outlet hole is provided on the push rod in the sliding hole, the air outlet hole is communicated with the axial through hole, and the inner diameter of the air outlet hole is smaller than the axial through hole.

4. The combined filtering device for a gas purification system according to claim 3, characterized in that: A valve plate is fixed in the return port, the valve plate abuts against the lower end of the sealing push block, the middle of the valve plate is used to close the axial through hole, and a connecting hole is arranged around the valve plate, and the inner diameter of the connecting hole is larger than the axial through hole.

5. The combined filtering device for a gas purification system according to claim 1, characterized in that: The first filter and the second filter both include an outer shell, a detachable end cap is provided at one end of the outer shell, an air inlet port is provided on the side wall of the outer shell, an air outlet connector is fixed at the other end of the outer shell, a second filter cartridge is provided in the outer shell, an air outlet end of the second filter cartridge is sealingly sleeved on the air outlet connector, and a compressed spring is provided between the sealing end of the second filter cartridge and the end cap.

6. The combined filtering device for a gas purification system according to claim 1, characterized in that: The main filter includes a filter shell, the left end of the filter shell is an air outlet end, and the right end is an air inlet end. A first filter cartridge is arranged in the filter shell, the left end of the first filter cartridge is fixedly connected to the air outlet end of the filter shell, and the right end of the first filter cartridge is a closed end. The filter cartridge includes a fine filter cartridge, and a coarse filter cartridge is mounted on the outer side of the fine filter cartridge.

Images