Multi-stage filtering and pressure stabilizing integrated gas source assembly

Abstract

The utility model discloses a multistage filtering and pressure stabilizing integrated air source assembly, which relates to the technical field of industrial air sources and comprises an air source base, a plurality of multistage filtering boxes are arranged at the upper end of the air source base and stacked above the air source base, a pressure stabilizing box is arranged at the upper ends of the multistage filtering boxes, and the pressure stabilizing box is arranged above the air source base. Spring telescopic rods are embedded in the air source base and the four corners of the upper ends of the multiple multi-stage filter boxes, and movable inner rods of the spring telescopic rods face upwards and are fixedly connected with the four corners of the bottoms of the adjacent multi-stage filter boxes and the pressure stabilizing box. Buckle connecting mechanisms are correspondingly arranged at the upper ends of the two sides of the air source base, the upper and lower parts of the two sides of the multi-stage filtering boxes and the lower edges of the two sides of the pressure stabilizing box, and through the arrangement of the air source base, the multiple multi-stage filtering boxes and the pressure stabilizing box, an operator can conveniently connect or disconnect the air source base, the multi-stage filtering boxes and the pressure stabilizing box through a quick connecting mechanism; rapid assembly and disassembly are realized, and the working efficiency is greatly improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to industrial gas source technical field, concretely relates to a multistage filtration and pressure stabilization integrated gas source assembly. BACKGROUND

[0002] When designing an industrial gas source system, a series of filtration and pressure regulating modules must be configured according to the requirements of a specific process, which include a multistage filtration system (such as filters for removing dust, grease, and dry gas) to ensure gas quality. Current solutions typically employ a split mounting approach, which means that the various components are connected together via flanges. While this design has certain advantages, it has the disadvantage of occupying a large amount of space and being inconvenient to disassemble and reassemble when performing maintenance or replacing parts. Taking a food packaging workshop as an example, regular replacement of filter cartridges is necessary in order to maintain the hygiene of the production environment and the quality of the products. However, in traditional designs, maintenance of the gas source assembly requires the removal of multiple bolts, which is not only time-consuming but also inefficient, negatively impacting production efficiency. To address this problem, we propose a multistage filtration and pressure stabilization integrated gas source assembly. SUMMARY

[0003] The utility model aims at: for solving in traditional design, the maintenance of gas source assembly needs to remove multiple bolts, this process is not only time -consuming but also inefficient, negatively impacts production efficiency's problem, the utility model provides a multistage filtration and pressure stabilization integrated gas source assembly.

[0004] The utility model discloses a multistage filtration and pressure stabilization integrated gas source assembly that comprises a gas source base, a plurality of multistage filtration boxes are arranged on the upper end of the gas source base, and the plurality of multistage filtration boxes are stacked on the upper end of the gas source base.

[0005] The utility model discloses a multistage filtration and pressure stabilization integrated gas source assembly that comprises a gas source base, a plurality of multistage filtration boxes are arranged on the upper end of the gas source base, and the plurality of multistage filtration boxes are stacked on the upper end of the gas source base.

[0006] Further, the buckle connection mechanism comprises a fixed buckle and a connecting buckle seat, the fixed buckle is fixedly connected to the lower edge of the upper multi-stage filter box and the pressure stabilizing box, and the fixed buckle is connected with an elastic hook plate, the connecting buckle seat is fixedly connected with the lower air source base and the upper edge of the multi-stage filter box in correspondence with the position of the fixed buckle, and the lower end of the elastic hook plate on the outer side of the fixed buckle is fixedly provided with a triangular protrusion in correspondence with the lower edge of the outer side of the connecting buckle seat.

[0007] Further, the buckle connection mechanism further comprises a connecting hinge seat, the connecting hinge seat is fixedly installed on the front and back sides of the air source base, the multi-stage filter box and the pressure stabilizing box, and the connecting hinge seat is hingedly connected with a connecting turnover arm, and the outer end of the connecting turnover arm close to one side of the air source base, the multi-stage filter box and the pressure stabilizing box is hingedly connected through a turnover connecting rod.

[0008] Further, the upper end of the multi-stage filter box is screw-connected with a positioning fastening bolt on the front side, and the upper end of the plug-in filter box is provided with a circular positioning groove in correspondence with the bottom of the positioning fastening bolt.

[0009] Further, the quick connection mechanism comprises a quick connection socket and a plug-in plug, the quick connection socket is arranged on the upper end of the rear side of the air source base and the multi-stage filter box, and the plug-in plug is fixedly installed on the rear side center of the bottom of the multi-stage filter box and the pressure stabilizing box, the plug-in plug is arranged in correspondence with the position of the quick connection socket, and the inner cavity of the multi-stage filter box is provided with a connecting elbow in correspondence with the quick connection socket and the plug-in plug, the inner cavity of the plug-in filter box is fixedly connected with a separation partition plate on the rear side center, and the rear side of the plug-in filter box is provided with an air inlet nozzle and an air outlet nozzle in correspondence with the separation partition plate, respectively, the inner side connecting elbow of the quick connection socket and the plug-in plug is arranged in correspondence with the air outlet nozzle and the air inlet nozzle on the inner side of the plug-in filter box, respectively.

[0010] Further, the air source base is provided with a gas supply pump, and the output end of the gas supply pump is connected with the inner end connecting elbow of the quick connection socket on the air source base through an output pressure stabilizing valve, the pressure stabilizing box is provided with a piezoelectric pilot pressure stabilizing valve and a gas path distribution valve, the input end of the piezoelectric pilot pressure stabilizing valve is communicated with the plug-in plug on the bottom of the pressure stabilizing box, the output end of the piezoelectric pilot pressure stabilizing valve is communicated with the input end of the gas path distribution valve through a pipeline, and the upper end of the gas path distribution valve is provided with a plurality of air source output interfaces.

[0011] Further, the groove bottom of the quick connection socket is provided with a rubber sealing gasket, and the outer side of the air outlet nozzle and the air inlet nozzle of the plug-in filter box is sleeved with a rubber sealing ring.

[0012] The beneficial effects of the utility model are as follows:

[0013] 1. The utility model discloses a gas source assembly which is compact in structure, stable in connection, simple in operation and good in filtering effect, and is suitable for various industrial production occasions requiring stable gas source.

[0014] 2. The utility model discloses a fixing buckle and connecting clamping seat are set up, the elastic hook plate of fixed buckle outside can be deformed when gas source base, multistage filter tank and pressure stabilizing tank press close, make the triangle convex block cross the outside of connecting clamping seat, and is clamped in the lower edge of connecting clamping seat, when separating, only need to move the lower edge of the elastic hook plate of fixed buckle outside outward, make the triangle convex block and the lower edge of connecting clamping seat separate, then multistage filter tank and pressure stabilizing tank can be lifted under the reset elastic force of spring telescopic link, simultaneously separate quick -wired mechanism, realize the disconnecting of gas circuit, and it is convenient to maintain operation and quick replacement filter core to multistage filter tank and pressure stabilizing tank, effectively improve the maintenance efficiency and use convenience of equipment.

[0015] 3. The utility model discloses a quick -wired socket and plug -in plug are set up, and quick -wired socket is inserted after being pressed close to gas source base, multistage filter tank and pressure stabilizing tank, can realize the quick -wired intercommunication of gas source base, multistage filter tank and pressure stabilizing tank, and the plug -in plug can ensure the stable connection of gas circuit between multistage filter tank and pressure stabilizing tank after being inserted to corresponding quick -wired socket, avoid the gas leakage problem that can appear in traditional flange connection mode. In addition, the design of quick -wired socket and plug -in plug makes the assembly and disassembly process of multistage filter tank and pressure stabilizing tank more simple and fast, and operating personnel can complete the connection without using tools, improve work efficiency greatly. Meanwhile, the use of quick -wired mechanism also reduces the equipment failure caused by bolt loosening or damage in the process of disassembly and assembly, enhances the reliability and stability of equipment. ACCURACY OF DRAWINGS

[0016] Figure 1 It is the perspective drawing of the utility model;

[0017] Figure 2 It is the utility model Figure 1 A place of the utility model is enlarged.

[0018] Figure 3is a side view of the utility model;

[0019] Figure 4 is the utility model Figure 3 is an enlarged view of B in the middle.

[0020] Reference Signs: 1, air source base; 2, air supply pump; 3, output pressure stabilizing valve; 4, multistage filter box; 5, spring telescopic rod; 6, connecting hinge base; 7, connecting turnover arm; 8, turnover connecting rod; 9, plug-in filter box; 10, separation partition; 11, quick connector socket; 12, plug-in plug; 13, pressure stabilizing box; 14, piezoelectric pilot pressure stabilizing valve; 15, air path distribution valve; 16, fixed buckle; 17, connecting buckle; 18, positioning fastening bolt. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the utility model embodiment more clear, the technical scheme in the utility model embodiment will be clearly and completely described below in combination with the drawings in the utility model embodiment.

[0022] Please refer to Figures 1-4 The utility model provides a multistage filtration and pressure stabilization integrated air source assembly, including air source base 1, the upper end of air source base 1 is provided with multiple multistage filter boxes 4, and multiple multistage filter boxes 4 are stacked and placed on the upper of air source base 1, the upper end of multiple multistage filter boxes 4 is provided with pressure stabilizing box 13, air source base 1 and the upper end of multiple multistage filter boxes 4 all are buried with spring telescopic rod 5 in four corners, and the movable inner rod of spring telescopic rod 5 is upwards and is fixedly connected with the bottom four corners of adjacent multistage filter box 4 and pressure stabilizing box 13, the upper end of both sides of air source base 1, the upper and lower of both sides of multistage filter box 4 and the lower of both sides of pressure stabilizing box 13 are provided with buckle connection mechanism correspondingly, and plug-in filter box 9 is inserted and fixed in the front side of multistage filter box 4, air source base 1, multiple multistage filter boxes 4 and pressure stabilizing box 13 rear side are provided with quick connector mechanism.

[0023] In this embodiment, preferably, the buckle connection mechanism comprises a fixed buckle 16 and a connecting buckle seat 17, the fixed buckle 16 is fixedly connected to the lower edge of the upper multi-stage filter box 4 and the pressure stabilizing box 13, and the fixed buckle 16 is connected with an elastic hook plate, the connecting buckle seat 17 is fixedly connected with the lower air source base 1 and the upper edge of the multi-stage filter box 4 corresponding to the position of the fixed buckle 16, and the inside lower end of the elastic hook plate outside the fixed buckle 16 is fixedly provided with a triangular lug corresponding to the lower edge outside the connecting buckle seat 17; through the fixed buckle 16 and the connecting buckle seat 17, the elastic hook plate outside the fixed buckle 16 can be deformed when the air source base 1, the multi-stage filter box 4 and the pressure stabilizing box 13 are pressed close, so that the triangular lug passes over the outside of the connecting buckle seat 17 and is clamped at the lower edge of the connecting buckle seat 17; when separated, only the lower edge of the elastic hook plate outside the fixed buckle 16 needs to be pushed outward, so that the triangular lug is separated from the lower edge of the connecting buckle seat 17, then the multi-stage filter box 4 and the pressure stabilizing box 13 can be lifted up under the reset elastic force of the spring telescopic rod 5, at the same time, the quick connection mechanism is separated, the gas circuit is disconnected, the multi-stage filter box 4 and the pressure stabilizing box 13 are maintained and operated, and the filter core is quickly replaced, thereby effectively improving the maintenance efficiency and use convenience of the equipment.

[0024] In this embodiment, preferably, the buckle connection mechanism further comprises a connecting hinge seat 6, the connecting hinge seat 6 is fixedly installed on the front and back of the two sides of the air source base 1, the multi-stage filter box 4 and the pressure stabilizing box 13, and the connecting hinge seat 6 is hingedly connected with a connecting turnover arm 7, and the outer end of the connecting turnover arm 7 on the close side of the air source base 1, the multi-stage filter box 4 and the pressure stabilizing box 13 is hingedly connected through a turnover connecting rod 8; through the connecting hinge seat 6, the connecting hinge seat 6, the connecting turnover arm 7 and the turnover connecting rod 8 can form a turnover connection structure between the air source base 1, the multi-stage filter box 4 and the pressure stabilizing box 13, thereby improving the connection stability of the air source base 1, the multi-stage filter box 4 and the pressure stabilizing box 13, and at the same time, when the air source base 1, the multi-stage filter box 4 or the pressure stabilizing box 13 needs to be disassembled and maintained, the multi-stage filter box 4 and the pressure stabilizing box 13 can be turned over at a certain angle relative to the air source base 1 through the turnover of the turnover connecting rod 8 and the connecting turnover arm 7, thereby facilitating the operator to observe and operate the inside of the assembly, and further improving the maintenance convenience of the equipment. In addition, this turnover connection structure can also absorb and relieve the vibration and impact force generated during equipment operation to a certain extent, protect the equipment assembly from damage, and prolong the service life of the equipment.

[0025] In this embodiment, preferably, the upper end of the multi-stage filter box 4 is threadedly connected with a positioning fastening bolt 18, and the upper end of the plug-in filter box 9 is provided with a circular positioning groove at the bottom of the corresponding positioning fastening bolt 18. The positioning fastening bolt 18 can lock and fix the plug-in filter box 9, which facilitates the disassembly and assembly of the plug-in filter box 9, and improves the installation stability and convenience of the plug-in filter box 9. At the same time, the design of the circular positioning groove enables the positioning fastening bolt 18 to accurately and quickly position and lock the plug-in filter box 9, avoiding the problem of loose sealing or loosening caused by installation deviation, and further ensuring the stability of the gas path and the filtering effect.

[0026] In this embodiment, preferably, the quick connection mechanism includes a quick connection socket 11 and a plug-in plug 12. The quick connection socket 11 is provided at the upper end of the rear side center of the gas source base 1 and the multi-stage filter box 4, and the plug-in plug 12 is fixedly installed at the bottom of the rear side center of the multi-stage filter box 4 and the pressure stabilizing box 13. The plug-in plug 12 is positioned corresponding to the quick connection socket 11, and the inner cavity of the multi-stage filter box 4 is provided with a connecting elbow corresponding to the quick connection socket 11 and the plug-in plug 12. The inner cavity of the plug-in filter box 9 is fixedly connected with a separation partition plate 10 at the rear side center, and the rear side of the plug-in filter box 9 is provided with an air inlet nozzle and an air outlet nozzle corresponding to the separation partition plate 10. The inner side connecting elbows of the quick connection socket 11 and the plug-in plug 12 are respectively provided corresponding to the air outlet nozzle and the air inlet nozzle on the left side of the plug-in filter box 9. Through the setting of the quick connection socket 11 and the plug-in plug 12, the quick connection socket 11 is pressed and close to the multi-stage filter box 4 and the pressure stabilizing box 13 after abutting, which can realize the quick connection and communication of the gas source base 1, the multi-stage filter box 4 and the pressure stabilizing box 13. After the plug-in plug 12 is inserted corresponding to the quick connection socket 11, it can ensure the stable connection of the gas path between the multi-stage filter box 4 and the pressure stabilizing box 13, avoiding the air leakage problem that may occur in the traditional flange connection mode. In addition, the design of the quick connection socket 11 and the plug-in plug 12 makes the assembly and disassembly process of the multi-stage filter box 4 and the pressure stabilizing box 13 more simple and convenient, and the operator can complete the connection without using tools, greatly improving the work efficiency. At the same time, the use of the quick connection mechanism also reduces the equipment failure caused by bolt loosening or damage in the disassembly process, and enhances the reliability and stability of the equipment.

[0027] In this embodiment, preferably, the gas source base 1 is provided with a gas supply pump 2, and the output end of the gas supply pump 2 is connected to the inner end connecting elbow of the quick connector socket 11 on the gas source base 1 through an output pressure stabilizing valve 3, and the pressure stabilizing box 13 is provided with a piezoelectric pilot pressure stabilizing valve 14 and a gas path distribution valve 15, the input end of the piezoelectric pilot pressure stabilizing valve 14 is communicated with the plug-in connector 12 at the bottom of the pressure stabilizing box 13, and the output end of the piezoelectric pilot pressure stabilizing valve 14 is communicated with the input end of the gas path distribution valve 15 through a pipeline, and the upper end of the gas path distribution valve 15 is provided with a plurality of gas source output interfaces; through the setting of the gas supply pump 2 and the pressure stabilizing box 13, the gas supply pump 2 can provide stable gas source, and the gas is preliminarily stabilized through the output pressure stabilizing valve 3, so as to ensure that the gas has stable pressure and flow before entering the multi-stage filter box 4. The piezoelectric pilot pressure stabilizing valve 14 in the pressure stabilizing box 13 can further finely stabilize the gas, and the piezoelectric pilot pressure stabilizing valve 14 uses a micro PID controller for control, when the downstream gas consumption suddenly changes, the PID controller dynamically adjusts the opening degree of the pilot valve according to the flow sensor (built-in Venturi tube), so as to ensure that the pressure of the output gas is stable, and meet the strict requirements of industrial production on the gas pressure. At the same time, the setting of the gas path distribution valve 15 enables the gas source assembly to simultaneously provide stable gas source for a plurality of gas using equipment, thereby improving the practicability and flexibility of the equipment.

[0028] In this embodiment, preferably, the groove bottom of the quick connector socket 11 is provided with a rubber sealing gasket, and the outer side of the gas outlet nozzle and the gas inlet nozzle of the plug-in filter box 9 is sleeved with a rubber sealing ring; through the setting of the rubber sealing gasket, the sealing property between the quick connector socket 11 and the plug-in connector 12 can be effectively enhanced, so as to prevent the gas from leaking at the connection position, and ensure the sealing property and stability of the gas path. At the same time, the design of the rubber sealing ring can also ensure that the connection between the gas inlet nozzle and the gas outlet nozzle of the plug-in filter box 9 and the quick connector socket 11 and the plug-in connector 12 is tight and leak-free, thereby further improving the overall sealing performance of the equipment. This design not only enhances the reliability and safety of the equipment, but also effectively avoids the problems of resource waste and environmental pollution caused by gas leakage, and meets the environmental protection and energy saving requirements of modern industrial production.

[0029] The working principle and use process of the utility model are as follows: when the device is used, the gas source base 1, the plurality of multi-stage filter boxes 4 and the pressure stabilizing box 13 are vertically stacked and installed on the upper side of the gas source base 1 through the four spring telescopic rods 5, the multi-stage filter boxes 4 and the pressure stabilizing box 13 are connected and separated through the buckle connection mechanism, the gas source base 1, the plurality of multi-stage filter boxes 4 and the pressure stabilizing box 13 are sequentially communicated through the quick connection mechanism, so that the gas source output by the gas source base 1 is filtered by the plug-in filter boxes 9 in the plurality of multi-stage filter boxes 4, and then is output after being stabilized by the pressure stabilizing box 13, the plurality of coarse filter modules are arranged in the multi-stage filter boxes 4 from bottom to top, the coarse filter modules use metal sintered filter elements (precision 5 μm), the processing capacity is 10 m 3 / h, pressure loss < 5kPa, one fine filter module, the fine filter module uses super oil - loving stainless steel fiber layer (precision 0.3 mu m) to filter oil, with liquid level sensing automatic oil drain valve, and a drying module, the drying module uses molecular sieve adsorption tower, humidity dew point -40 DEG C, regeneration period > 200h, improve the purity and stability of gas.In the use process, the operator can conveniently connect or disconnect the gas source base 1, the multistage filter box 4 and the pressure stabilizing box 13 through the quick -wired mechanism, realize quick assembly and disassembly, greatly improve work efficiency.The utility model provides a kind of compact structure, connection stable, easy to operate and good filtering effect multistage filtration and pressure stabilizing integrated gas source assembly, it is applicable to various need stable gas source industrial production occasion.

[0030] The above description of disclosed embodiments enables those skilled in the art to carry out or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, the present application will not be limited to these embodiments shown herein, but will accord with the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multi-stage filtration and pressure stabilization integrated gas source assembly, characterized in that: The utility model provides a multi -level filter box, gas source base (1) is provided with a plurality of multistage filter box (4) on the upper end, and a plurality of multistage filter box (4) is stacked on the upper end of gas source base (1), and the upper end of a plurality of multistage filter box (4) is provided with pressure stabilizing tank (13), and the upper end of gas source base (1) and a plurality of multistage filter box (4) is buried with spring telescopic link (5) in four corners, and the movable inner rod of spring telescopic link (5) is fixedly connected with the bottom four corners of adjacent multistage filter box (4) and pressure stabilizing tank (13) upwards, and the upper end of both sides of gas source base (1), the upper and lower sides of both sides of multistage filter box (4) and the lower side of both sides of pressure stabilizing tank (13) are provided with buckle connection mechanism correspondingly, and the front side of multistage filter box (4) is fixedly connected with plug -in filter box (9), and the rear side of gas source base (1), a plurality of multistage filter box (4) and pressure stabilizing tank (13) is provided with quick -wired mechanism.

2. The multi-stage filtering and pressure stabilizing integrated gas source assembly according to claim 1, characterized in that: The buckle connection mechanism includes fixed buckle (16) and connecting buckle seat (17), the fixed buckle (16) is fixedly connected to the lower edge of the upper multistage filter box (4) and the pressure stabilizing tank (13), and the fixed buckle (16) is connected with the elastic hook plate, the connecting buckle seat (17) is fixedly connected with the upper edge of the lower gas source base (1) and the multistage filter box (4) at the position corresponding to the fixed buckle (16), and the inner lower end of the elastic hook plate outside the fixed buckle (16) is fixedly provided with a triangular protrusion corresponding to the lower edge outside the connecting buckle seat (17).

3. The multi-stage filtering and pressure stabilizing integrated gas source assembly according to claim 2, characterized in that: The buckle connection mechanism further includes a connecting hinge seat (6), which is fixedly installed on the front and back of both sides of the gas source base (1), the multistage filter box (4) and the pressure stabilizing tank (13), and the connecting hinge seat (6) is hingedly connected with a connecting turnover arm (7) on the upper side, and the outer end of the connecting turnover arm (7) on the side close to the gas source base (1), the multistage filter box (4) and the pressure stabilizing tank (13) is hingedly connected through a turnover connecting rod (8).

4. The multi-stage filtering and pressure stabilizing integrated gas source assembly of claim 1, wherein: The upper end of the multistage filter box (4) is threadedly connected with a positioning fastening bolt (18), and the upper end of the plug-in filter box (9) is provided with a circular positioning groove corresponding to the bottom of the positioning fastening bolt (18).

5. The multi-stage filtering and pressure stabilizing integrated gas source assembly according to claim 4, characterized in that: The quick -wired mechanism includes quick -wired socket (11) and plug -in plug (12), the quick -wired socket (11) is provided in the center of the upper end of the rear side of the gas source base (1) and the multistage filter box (4), and the plug -in plug (12) is fixedly installed in the center of the bottom rear side of the multistage filter box (4) and the pressure stabilizing tank (13), the plug -in plug (12) is provided at the position corresponding to the quick -wired socket (11), and the inner cavity of the multistage filter box (4) is provided with a connecting elbow corresponding to the quick -wired socket (11) and the plug -in plug (12), the inner cavity of the plug -in filter box (9) is fixedly connected with a separation baffle (10) in the center of the rear side, and the rear side of the plug -in filter box (9) is provided with an air inlet and an air outlet respectively corresponding to the separation baffle (10) on the upper and lower sides, and the inner side connecting elbow of the quick -wired socket (11) and the plug -in plug (12) is respectively provided corresponding to the air outlet and the air inlet on the inner side of the plug -in filter box (9).

6. The multi-stage filtering and pressure stabilizing integrated gas source assembly according to claim 5, characterized in that: The gas source base (1) is provided with a gas supply pump (2), and the output end of the gas supply pump (2) is connected with the inner end connecting elbow of the quick connector socket (11) on the gas source base (1) through an output pressure stabilizing valve (3), a piezoelectric pilot pressure stabilizing valve (14) and a gas path distribution valve (15) are arranged in the pressure stabilizing box (13), the input end of the piezoelectric pilot pressure stabilizing valve (14) is communicated with the plug-in plug (12) at the bottom of the pressure stabilizing box (13), the output end of the piezoelectric pilot pressure stabilizing valve (14) is communicated with the input end of the gas path distribution valve (15) through a pipeline, and a plurality of gas source output interfaces are arranged at the upper end of the gas path distribution valve (15).

7. The multi-stage filtering and pressure stabilizing integrated gas source assembly of claim 5, wherein: The groove bottom of the quick connector socket (11) is provided with a rubber sealing gasket, and the outer side of the air outlet nozzle and the air inlet nozzle of the plug-in filter box (9) is sleeved with a rubber sealing ring.

Images