Fresh air handling unit system for clean room

Abstract

This invention relates to the field of air ventilation technology, specifically a fresh air handling unit system for cleanrooms. The system includes a return air handling box, a filter assembly, and an auxiliary control assembly. An inlet duct and an outlet duct are respectively connected to both sides of the return air handling box. An opening and closing assembly, including a sealing seat and a baffle, is located on one side of the inlet duct connecting to the return air handling box. The filter assembly is housed within the return air handling box. When processing return air from the cleanroom, the filter assembly within the return air handling box allows for refined filtration, achieving high-quality dust removal and dehumidification. The auxiliary control assembly adjusts the airflow direction of the centrifugal fan within the return air handling box, thereby assisting in the self-cleaning of the tubular ceramic inorganic membrane and the primary filter plate. This improves the quality and efficiency of the return air handling box in processing cleanroom return air, and the system is fully functional and easy to operate.

Description

Technical Field

[0001] This invention relates to the field of air ventilation technology, specifically to a fresh air handling unit system for clean rooms. Background Technology

[0002] A cleanroom is a special spatial environment that uses specialized design and technical measures to control the concentration of pollutants such as dust and microorganisms in the indoor air within a specific range, while strictly regulating parameters such as temperature, humidity, pressure, and airflow organization. Its core purpose is to ensure that the indoor environment meets the cleanliness requirements of high-quality production, scientific research, or medical scenarios. The fresh air unit system is its "breathing system," which is not only responsible for introducing clean fresh air, but also provides core guarantees for the environmental stability and operational efficiency of the cleanroom through temperature and humidity regulation, pressure control, and energy-saving design.

[0003] A novel air purification system for cleanrooms, disclosed in publication number CN215809048U, includes a circulating unit containing a filter, a laminar flow air supply box, a fresh air unit, and a return air outlet located below the laminar flow air supply box. This solution improves the stability of the circulating unit's service life, energy consumption, and air resistance, and also enhances the efficiency and automation of cleaning lint from the filter screen. In energy-saving applications in cleanrooms, the fresh air unit system needs to reprocess the indoor return air before mixing it with the fresh air and then sending it into the cleanroom. When processing the return air in the cleanroom, the return airflow may contain a certain amount of dust and moisture due to the limitations of the cleanroom's operating conditions. Existing return air treatment systems often only use one or more filter plates for filtration, which need to be disassembled and replaced after prolonged use. The functionality is relatively simple, and the filter plates are not easy to maintain automatically. Summary of the Invention

[0004] The purpose of this invention is to provide a fresh air handling unit system for clean rooms to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a fresh air handling unit system for cleanrooms, comprising:

[0006] A return air treatment box, wherein an air inlet pipe and an air outlet pipe are respectively connected to both sides of the return air treatment box, and an opening and closing assembly is provided on the side of the air inlet pipe connected to the return air treatment box, the opening and closing assembly including a sealing seat and a baffle.

[0007] The filter assembly is located inside the return air treatment box. The filter assembly includes a primary filter plate, an assembly partition, several reference plates, and several tubular ceramic inorganic membranes. The reference plates are respectively fixed to the assembly partition by bolts. The tubular ceramic inorganic membranes are respectively located between the primary filter plate and the assembly partition. One side of each tubular ceramic inorganic membrane is respectively located on one side of the reference plate by a support assembly. The support assembly includes a mounting support rod and a mounting end cap.

[0008] The auxiliary control component includes a centrifugal fan located on the side of the return air treatment box near the air outlet duct, and a control chamber at the lower end of the return air treatment box. The auxiliary control component includes a flow-blocking movable box, a control arm, and a scraper. The flow-blocking movable box is movably disposed in the control chamber and is connected to the scraper and the wind baffle.

[0009] Preferably, one side of the sealing seat is inserted into the air inlet duct and has an inclined guide surface, and the side of the sealing seat located in the return air treatment box has a cross groove, and the wind baffle is vertically slidably inserted into the cross groove.

[0010] Preferably, the primary filter plate is vertically arranged inside the return air treatment box on the side near the air inlet pipe, and the assembly partition is vertically arranged between the primary filter plate and the air outlet pipe inside the return air treatment box. The assembly partition has several recessed mounting slots horizontally through it, and several reference plates are respectively connected to the several recessed mounting slots by bolts.

[0011] Preferably, the reference plate has a combined groove on one side that passes through the recessed mounting groove and is close to the primary filter plate. One end of the tubular ceramic inorganic membrane is horizontally inserted into the combined groove. Several gap grooves are formed inside the tubular ceramic inorganic membrane. A ventilation bracket is provided at the center of one side of the reference plate. A mounting support rod is horizontally positioned at the center of one side of the ventilation bracket. One side of the mounting support rod horizontally passes through the tubular ceramic inorganic membrane. A diatomaceous earth dehumidification sleeve is fitted onto the mounting support rod.

[0012] Preferably, the mounting support rod has an external thread on one side of the tubular ceramic inorganic membrane. The mounting end cap is fitted with the external thread of the mounting support rod. One side of the mounting end cap has a hexagonal plate with three guide holes. Each of the three guide holes is fitted with an L-shaped pull rod. The L-shaped pull rod passes through the hexagonal plate and is fitted with a support spring by a spring pressure plate on the side near the assembly partition. The end of the L-shaped pull rod with the support spring has a vertical release push rod. The distance between the end of the release push rod and the central axis of the mounting support rod is greater than the radius of the tubular ceramic inorganic membrane.

[0013] Preferably, the center of the mounting support rod is provided with a back-blowing groove through the ventilation bracket, and the ends of the three L-shaped tie rods away from the assembly partition are provided with a sealing block. One side of the sealing block is set with a conical structure, and the conical side of the sealing block is inserted into the back-blowing groove of the mounting support rod.

[0014] Preferably, a cleaning window is provided at the upper end of the control cavity between the primary filter plate and the air inlet pipe, and a dust discharge pipe is connected to the lower end of the return air treatment box located on the side of the cleaning window. Two first connecting ears are symmetrically provided on the side of the cleaning window of the wind baffle, and two second connecting ears are symmetrically provided on the side of the intercepting movable box near the cleaning window. A control arm is provided between the two first connecting ears and the two second connecting ears respectively through a pin.

[0015] Preferably, the lower end of the control cavity located between the primary filter plate and the assembly partition in the return air treatment box has two strip-shaped grooves. The upper end of the flow interception movable box is vertically provided with two synchronous pull rods. The upper ends of the two synchronous pull rods pass through the strip-shaped grooves and are inserted into the return air treatment box. The two synchronous pull rods are vertically provided with a scraper plate on one side inside the return air treatment box. The scraper plate has several scraping holes, and annular scraper strips are inserted into each scraping hole. The vertical cross-sectional area of ​​the flow interception movable box is equal to the vertical cross-sectional area of ​​the control cavity, and the length of the flow interception movable box is greater than the length of the strip-shaped grooves.

[0016] Preferably, a control telescopic cylinder is horizontally provided on the side of the control cavity near the air outlet pipe, and a U-shaped control frame is horizontally provided at one end of the control telescopic cylinder. One side of the U-shaped control frame is connected to the side of the intercepting movable box away from the air inlet pipe. A synchronous shaft is vertically provided at the lower end of the centrifugal fan. The lower end of the synchronous shaft is rotatably inserted into the control cavity and is provided with a switching gear. A number of actuating teeth are provided on the side of the U-shaped control frame near the switching gear, and one side of the switching gear is meshed with the actuating teeth.

[0017] Preferably, a partition plate is vertically installed inside the return air treatment box between the centrifugal fan and the air outlet pipe. The partition plate has a docking hole. During normal use, the air outlet of the centrifugal fan corresponds to the docking hole of the partition plate, and a sealing film is provided on the side of the centrifugal fan near the partition plate.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] When treating the return air of a cleanroom, the return air handling unit of the fresh air handling unit system can perform fine filtration of the return air through the matching filter components, achieving high-quality dust removal and dehumidification. Then, with the help of the auxiliary control components, the centrifugal fan in the return air handling unit can adjust the airflow direction, thereby assisting the self-cleaning of the tubular ceramic inorganic membrane and the primary filter plate, improving the quality and efficiency of the return air handling unit in treating the cleanroom return air. It is also fully functional and easy to operate. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the present invention;

[0021] Figure 2 This is a schematic diagram of the internal layout of the present invention;

[0022] Figure 3 For the present invention Figure 2 Schematic diagram of part A;

[0023] Figure 4 This is a schematic diagram of the side cross-section structure of the present invention;

[0024] Figure 5 For the present invention Figure 4 Schematic diagram of part B;

[0025] Figure 6 For the present invention Figure 4 Schematic diagram of part C;

[0026] Figure 7 For the present invention Figure 6 Schematic diagram of part D;

[0027] Figure 8 For the present invention Figure 6 Schematic diagram of part E;

[0028] Figure 9 This is a schematic diagram of the tubular ceramic inorganic membrane mating structure of the present invention;

[0029] Figure 10 This is a schematic diagram of the closure mechanism of the present invention.

[0030] Figure 11 For the present invention Figure 10 Schematic diagram of part F;

[0031] Figure 12 This is an exploded view of the tubular ceramic inorganic membrane connection of the present invention.

[0032] In the diagram: 1. Return air treatment box; 2. Inlet air pipe; 3. Outlet air pipe; 4. Sealing seat; 5. Cross slide groove; 6. Wind baffle; 7. Primary filter plate; 8. Assembly partition; 9. Recessed installation groove; 10. Base plate; 11. Tubular ceramic inorganic membrane; 12. Installation support rod; 13. Diatomaceous earth dehumidification sleeve; 14. Installation end cover; 15. Hexagonal plate; 16. Sealing block; 17. L-shaped pull rod; 18. Support spring; 19. Release push rod; 20. Centrifugal fan; 21. Control chamber; 22. Interception movable box; 23. Control arm; 24. Cleaning window; 25. Dust exhaust pipe; 26. Scraper; 27. Circular scraper; 28. Synchronous pull rod; 29. ​​Synchronous shaft; 30. Switching gear; 31. Control telescopic cylinder; 32. U-shaped control frame; 33. Actuating teeth; 34. Partition plate; 35. Ventilation bracket. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Please see the appendix Figure 1-12 This application provides the following technical solutions.

[0035] A fresh air handling unit system for cleanrooms includes a return air treatment box 1. An inlet pipe 2 and an outlet pipe 3 are respectively connected to both sides of the return air treatment box 1. An opening and closing assembly is provided on the side of the inlet pipe 2 connected to the return air treatment box 1. The opening and closing assembly includes a sealing seat 4 and a baffle 6. One side of the sealing seat 4 is inserted into the inlet pipe 2 and has an inclined guide surface. A cross groove 5 is opened on the side of the sealing seat 4 located inside the return air treatment box 1. The baffle 6 is vertically slidably inserted into the cross groove 5. Air in the cleanroom is connected to the inlet pipe 2 through the return air duct. At this time, the return air enters the return air treatment box 1 from the inlet pipe 2, is processed in the return air treatment box 1, and is blown out from the outlet pipe 3, awaiting subsequent re-entry into the cleanroom through the duct. The sealing seat 4 guides and seals the return air passing through the inlet pipe 2. The baffle 6 slides stably up and down within the cross groove 5, enabling the baffle 6 to seal and open the inlet pipe 2.

[0036] A filter assembly is installed inside the return air treatment box 1 to treat the return air from the cleanroom. The filter assembly includes a primary filter plate 7, an assembly partition 8, several reference plates 10, and several tubular ceramic inorganic membranes 11. The reference plates 10 are bolted to the assembly partition 8. The tubular ceramic inorganic membranes 11 are located between the primary filter plate 7 and the assembly partition 8, with one side of each membrane attached to one side of a reference plate 10 via a support assembly. The support assembly includes a mounting support rod 12 and a mounting end cap 14. The primary filter plate 7 is vertically positioned inside the return air treatment box 1 near the inlet duct 2. The assembly partition 8 is vertically positioned between the primary filter plate 7 and the outlet duct 3 inside the return air treatment box 1. A number of recessed mounting slots 9 are horizontally opened at the top. A number of reference plates 10 are respectively installed by bolts through and inserting into the recessed mounting slots 9. A combination groove is opened on the side of the reference plate 10 through the recessed mounting slots 9 and close to the primary filter plate 7. One end of the tubular ceramic inorganic membrane 11 is horizontally inserted into the combination groove. A number of gap slots are opened in the tubular ceramic inorganic membrane 11. A ventilation bracket 35 is provided at the center of one side of the reference plate 10. A mounting support rod 12 is horizontally set at the center of one side of the ventilation bracket 35. The side of the mounting support rod 12 horizontally penetrates the tubular ceramic inorganic membrane 11. A diatomaceous earth dehumidification sleeve 13 is sleeved on the mounting support rod 12. The return air entering the clean room from the air inlet duct 2 enters the return air treatment box 1 from the air inlet duct 2 and first contacts the primary filter plate 7 for preliminary filtration.

[0037] The mounting support rod 12 has an external thread that penetrates one side of the tubular ceramic inorganic membrane 11. The mounting end cap 14 is fitted with the external thread of the mounting support rod 12. One side of the mounting end cap 14 has a hexagonal plate 15 with three guide holes. Each of the three guide holes is fitted with an L-shaped pull rod 17. The L-shaped pull rod 17 penetrates the hexagonal plate 15 and is fitted with a support spring 18 via a spring pressure plate on the side near the assembly partition 8. The center of the mounting support rod 12 has a back-blowing groove that penetrates the ventilation bracket 35. The ends of the three L-shaped pull rods 17 away from the assembly partition 8 are fitted with a sealing block 16. One side of the sealing block 16 has a conical structure, and the conical side of the sealing block 16 is inserted into the back-blowing groove of the mounting support rod 12. After the reference plate 10 is fixedly connected to the assembly partition 8, the mounting groove 9 and one end of the reference plate 10 can be lowered. The tubular ceramic inorganic membrane 11 is horizontally inserted into the reference plate 10. At this time, the tubular ceramic inorganic membrane 11 is sleeved on the outside of the diatomaceous earth dehumidification sleeve 13 and the mounting support rod 12. Then, it is connected to the mounting support rod 12 by the threaded connection of the sealing seat 4. The mounting end cap 14 presses the tubular ceramic inorganic membrane 11 against the reference plate 10. At this time, the tubular ceramic inorganic membrane 11 is pressed and fixed. The return air in the clean room after preliminary filtration by the primary filter plate 7 will pass through the porous structure of the reference plate 10 itself, and then flow from the ventilation bracket 35 of the reference plate 10 to the centrifugal fan 20 area in the return air treatment box 1. It is blown by the centrifugal fan 20 to the air outlet duct 3. When passing through the tubular ceramic inorganic membrane 11, finer dust and basic water vapor are intercepted, realizing high-quality filtration treatment of the clean room. The tubular ceramic inorganic membrane 11 is also easy to replace and maintain.

[0038] An auxiliary control component is set up to control the sealing of the air inlet pipe 2 by the wind baffle 6 and to maintain the tubular ceramic inorganic membrane 11. A centrifugal fan 20 is installed in the return air treatment box 1 near the air outlet pipe 3. A control chamber 21 is opened at the lower end of the return air treatment box 1. The auxiliary control component includes a flow interception movable box 22, a control arm 23, and a scraper 26. The flow interception movable box 22 is movably installed in the control chamber 21 and is connected to the scraper 26 and the wind baffle 6. A cleaning window 24 is opened at the upper end of the control chamber 21 between the primary filter plate 7 and the air inlet pipe 2. The lower end of the cleaning box 1 located at the cleaning window 24 is connected to a dust exhaust pipe 25. The air baffle 6 is symmetrically provided with two first connecting ears on one side of the cleaning window 24. The flow intercepting movable box 22 is symmetrically provided with two second connecting ears on the side near the cleaning window 24. The two first connecting ears are connected to the two second connecting ears by a control arm 23 through a pin. When the flow intercepting movable box 22 moves horizontally towards the air inlet pipe 2, the air baffle 6 will be lifted upward along the cross groove 5 under the pushing action of the control arm 23. At this time, the air baffle 6 can block the air inlet pipe 2.

[0039] The lower end of the control cavity 21, located between the primary filter plate 7 and the assembly partition plate 8, in the return air treatment box 1 has two strip-shaped slots. Two synchronous pull rods 28 are vertically mounted on the upper end of the flow-stopping movable box 22. The upper ends of the two synchronous pull rods 28 pass through the strip-shaped slots and are inserted into the return air treatment box 1. A scraper plate 26 is vertically mounted on one side of the two synchronous pull rods 28 inside the return air treatment box 1. Several scraping holes are opened on the scraping plate 26, and annular scraper strips 27 are inserted into each of the scraping holes. The vertical cross-sectional area of ​​the flow-stopping movable box 22 is equal to the vertical cross-sectional area of ​​the control cavity 21, and the length of the flow-stopping movable box 22 is greater than the length of the strip-shaped slots. A release push rod 19 is vertically mounted on one end of the L-shaped pull rod 17, which has a support spring 18. The end of the release push rod 19 is located at a distance from... The distance between the central axis of the mounting support rod 12 is greater than the radius of the tubular ceramic inorganic membrane 11. The surface of the intercepting movable box 22 can be fitted with a rubber sleeve to intercept the air in the control chamber 21. When the intercepting movable box 22 moves horizontally in the control chamber 21, the air in the return air treatment box 1 that has not been filtered by the primary filter plate 7 will not enter the space between the primary filter plate 7 and the assembly partition plate 8 from the control chamber 21 and the strip groove. When the intercepting movable box 22 moves, in addition to lifting and controlling the wind baffle 6, it can also pull the scraper plate 26 to move horizontally. At this time, the scraper plate 26 scrapes the surface of the tubular ceramic inorganic membrane 11 through several annular scraper strips 27 to scrape away any dust accumulation and condensed water droplets that may exist on the surface of the tubular ceramic inorganic membrane 11.

[0040] Meanwhile, as the scraper plate 26 continues to move along the tubular ceramic inorganic membrane 11, the scraper plate 26 can push the release rod 19 to control the sealing block 16 to disengage from the backflush groove of the plug-in mounting support rod 12.

[0041] A control telescopic cylinder 31 is horizontally installed on the side of the control chamber 21 near the air outlet duct 3. A U-shaped control frame 32 is horizontally installed at one end of the control telescopic cylinder 31. One side of the U-shaped control frame 32 is connected to the side of the flow-stopping movable box 22 away from the air inlet duct 2. A synchronous shaft 29 is vertically installed at the lower end of the centrifugal fan 20. The lower end of the synchronous shaft 29 is rotatably inserted into the control chamber 21 and is equipped with a switching gear 30. Several actuating teeth 33 are provided on the side of the U-shaped control frame 32 near the switching gear 30, and one side of the switching gear 30 is meshed with the actuating teeth 33. The movement control of the flow-stopping movable box 22 is achieved by the reciprocating control of the control telescopic cylinder 31 pushing the U-shaped control frame 32. When the U-shaped control frame 32 moves horizontally, the actuating teeth... Under the action of 33, the centrifugal fan 20 can rotate within the return air treatment box 1. Simultaneously, as the U-shaped control frame 32 moves towards the air inlet duct 2, the damper 6 rises to close the air inlet duct 2, and the scraper plate 26 cleans the tubular ceramic inorganic membrane 11. The air outlet of the centrifugal fan 20 faces the assembly partition 8. After the centrifugal fan 20 starts, the air in the return air treatment box 1 is guided by the centrifugal fan 20 and blown at high speed towards several reference plates 10. Then, guided by the ventilation bracket 35 and the back-blowing groove, the tubular ceramic inorganic membrane 11 and the primary filter plate 7 are back-blown. The airflow generated by the back-blowing, due to the closure of the air inlet duct 2, can be discharged from the cleaning window 24 and the dust exhaust pipe 25, achieving the collection of dust-laden airflow. The primary filter plate 7 and the tubular ceramic inorganic membrane 11 are automatically cleaned. When the dust exhaust pipe 25 is used in the fresh air unit system, it is closed by a ball valve.

[0042] Inside the return air treatment box 1, a vertical partition plate 34 is installed between the centrifugal fan 20 and the air outlet duct 3. The partition plate 34 has a docking hole. During normal use, the air outlet of the centrifugal fan 20 corresponds to the docking hole of the partition plate 34. The side of the centrifugal fan 20 closest to the partition plate 34 is equipped with a sealing film. When the fresh air unit system is in normal use, the air inlet duct 2 is opened, the scraper plate 26 is attached to the partition plate 8, and the air outlet of the centrifugal fan 20 is pressed tightly against the partition plate 34 under the pulling action of the U-shaped control frame 32, so that the cleanroom return air that has passed through the primary filter plate 7 and the tubular ceramic inorganic membrane 11 is sent to the next stage.

[0043] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A fresh air handling unit system for a clean room, characterized by, The utility model relates to a kind of air return treatment boxes, including: Air return treatment box (1), the two sides of the air return treatment box (1) are respectively communicated with air inlet pipe (2) and air outlet pipe (3), air inlet pipe (2) is communicated with the side of air return treatment box (1) and is equipped with opening and closing assembly, opening and closing assembly includes plugging seat (4) and air baffle (6); Cooperative filtering assembly, the cooperative filtering assembly is equipped in air return treatment box (1), cooperative filtering assembly includes primary filter plate (7), assembly partition (8), several datum disc (10) and several tubular ceramic inorganic membrane (11), several datum disc (10) are respectively fixed by bolt and are inserted in assembly partition (8), several tubular ceramic inorganic membrane (11) are respectively located between primary filter plate (7) and assembly partition (8), and the side of several tubular ceramic inorganic membrane (11) is respectively equipped with the side of datum disc (10) by support assembly, support assembly includes installation support rod (12) and installation end cover (14); Auxiliary control assembly, the side of air return treatment box (1) is equipped with centrifugal fan (20) close to air outlet pipe (3), the lower end of air return treatment box (1) is equipped with control cavity (21), auxiliary control assembly includes intercepting movable box (22), control arm rod (23) and scraping plate (26), intercepting movable box (22) is movably equipped in control cavity (21), intercepting movable box (22) is connected with scraping plate (26) and air baffle (6); The side of plugging seat (4) is inserted into air inlet pipe (2) and is equipped with inclined flow face, plugging seat (4) is located in the side of air return treatment box (1) and is equipped with cross slide groove (5), air baffle (6) is vertically inserted into cross slide groove (5) and is slidably connected; The upper end of control cavity (21) is equipped with cleaning window (24) between primary filter plate (7) and air inlet pipe (2), the lower end of the side of air return treatment box (1) is communicated with dust removal pipe (25) at the position of cleaning window (24), air baffle (6) is symmetrically equipped with two first connecting ears on the side of cleaning window (24), intercepting movable box (22) is symmetrically equipped with two second connecting ears on the side close to cleaning window (24), two first connecting ears are respectively connected with two second connecting ears by pin shaft and are equipped with control arm rod (23); The lower end of air return treatment box (1) is equipped with two strip grooves in control cavity (21) between primary filter plate (7) and assembly partition (8), the upper end of intercepting movable box (22) is vertically equipped with two synchronous pull rods (28), the upper end of two synchronous pull rods (28) is respectively penetrated through strip groove and is inserted into air return treatment box (1), two synchronous pull rods (28) are vertically equipped with scraping plate (26) on the side in air return treatment box (1), scraping plate (26) is equipped with several scraping holes, ring-shaped scraping strip (27) is inserted into scraping hole, the vertical section area of intercepting movable box (22) is equal to the vertical section area of control cavity (21), and the length of intercepting movable box (22) is greater than the length of strip groove; The control cavity (21) is horizontally provided with a control telescopic cylinder (31) near one side of the air outlet pipe (3), one end of the control telescopic cylinder (31) is horizontally provided with a U-shaped control frame (32), one side of the U-shaped control frame (32) is connected with the side of the cut-off movable box (22) away from the air inlet pipe (2), the lower end of the centrifugal fan (20) is vertically provided with a synchronous shaft (29), the lower end of the synchronous shaft (29) is rotatably inserted into the control cavity (21) and provided with a switching gear (30), one side of the U-shaped control frame (32) near the switching gear (30) is provided with a plurality of shifting teeth (33), and one side of the switching gear (30) is connected with the shifting teeth (33) in meshing engagement.

2. The fresh air handling unit system for a clean room according to claim 1, wherein: The preliminary filter plate (7) is vertically arranged in the air return treatment box (1) near one side of the air inlet pipe (2), the assembly partition plate (8) is vertically arranged between the preliminary filter plate (7) and the air outlet pipe (3) in the air return treatment box (1), a plurality of sunken installation grooves (9) are horizontally and penetratingly formed in the assembly partition plate (8), and a plurality of reference discs (10) are respectively arranged in the sunken installation grooves (9) by penetratingly inserting and connecting through bolts.

3. The fresh air handling unit system for a clean room according to claim 2, wherein: The reference disc (10) is penetratingly arranged in the sunken installation groove (9) and is provided with a combined groove on one side near the preliminary filter plate (7), one end of the tubular ceramic inorganic membrane (11) is inserted into the combined groove, a plurality of gap grooves are formed in the tubular ceramic inorganic membrane (11), a ventilation support (35) is arranged on one side of the reference disc (10), an installation support rod (12) is horizontally arranged on one side of the ventilation support (35), one side of the installation support rod (12) is horizontally penetratingly arranged in the tubular ceramic inorganic membrane (11), and a diatomite dehumidification sleeve (13) is sleeved on the installation support rod (12).

4. The fresh air handling unit system for a clean room according to claim 3, wherein: One side of the installation support rod (12) penetratingly arranged in the tubular ceramic inorganic membrane (11) is provided with an external thread, an installation end cover (14) is sleeved on the external thread of the installation support rod (12), one side of the installation end cover (14) is provided with a hexagonal plate (15), three guide holes are penetratingly formed in the hexagonal plate (15), three L-shaped pull rods (17) are penetratingly and insertingly arranged in the hexagonal plate (15), a support spring (18) is sleeved on one side of the L-shaped pull rod (17) penetratingly arranged in the hexagonal plate (15) and close to the assembly partition plate (8) through a spring pressing plate, one end of the L-shaped pull rod (17) provided with the support spring (18) is vertically provided with a release push rod (19), and the distance between the end of the release push rod (19) and the central axis of the installation support rod (12) is greater than the radius length of the tubular ceramic inorganic membrane (11).

5. The fresh air handling unit system for a clean room according to claim 4, wherein: The central part of the installation support rod (12) penetratingly arranged in the ventilation support (35) is provided with a back-blowing groove, the ends of the three L-shaped pull rods (17) away from the assembly partition plate (8) are collectively provided with a blocking block (16), one side of the blocking block (16) is provided in a conical structure, and the conical structure of the blocking block (16) is insertingly arranged in the back-blowing groove of the installation support rod (12).

6. The fresh air handling unit system for a clean room according to claim 5, wherein: The return air treatment box (1) is vertically provided with a partition plate (34) between the centrifugal fan (20) and the air outlet pipe (3), the partition plate (34) is provided with a butt joint hole, the blowing port of the centrifugal fan (20) corresponds to the butt joint hole of the partition plate (34) in normal use, and the side of the centrifugal fan (20) close to the partition plate (34) is provided with a sealing rubber sheet.

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