Pneumatic actuator for angle rotation type valve

Abstract

The utility model discloses a pneumatic actuator used for an angle rotation type valve, and relates to the technical field of pneumatic actuators, the pneumatic actuator comprises a shell and a connecting block, the bottom of the shell is provided with a connecting assembly, the bottom of the connecting assembly is provided with a pipeline, the left side of the shell is provided with a groove 2, and the groove 2 is provided with a groove 3. First threaded holes are formed in the left side and the right side of the shell correspondingly, a third groove is formed in the top of the shell, a limiting screw is in threaded connection with the front side of the shell, a first baffle is arranged on the outer side of the connecting block, the section of the first baffle is of an L-shaped structure, and a sleeve is arranged in the connecting assembly. According to the pneumatic actuator for the angle rotation type valve, through the arrangement of the guide plate and the guide groove, a worker inserts the guide plate into the guide groove, aligns the first kidney-shaped holes with the second kidney-shaped holes and fixes the guide plate through the third bolts, and through the design of the first kidney-shaped holes and the second kidney-shaped holes, the adjustable effect is achieved, and the adaptation performance of a connecting assembly is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of pneumatic actuators, in particular to a pneumatic actuator used for an angle rotating valve. Background Art

[0002] Pneumatic actuators are devices that use air pressure to drive the opening, closing or regulating of valves. They are also called pneumatic actuators or pneumatic devices, but they are generally called pneumatic heads. Pneumatic actuators are actuators powered by compressed air. They are generally composed of a pneumatic actuator and a regulating mechanism to form a pneumatic regulator. Traditional pneumatic actuators are equipped with a main shaft, a cylinder and a piston. The piston moves in the cylinder to drive the main shaft.

[0003] The Chinese utility model patent announcement number: CN218441150U discloses: a pneumatic actuator for a valve, the pneumatic actuator for the valve, the anti-breaking shaft setting can prevent the output shaft from twisting and deforming, or even breaking when the valve shaft cannot rotate. When the torsional stress between the output shaft and the valve shaft is too large, the connecting block breaks, causing the docking sleeve to detach from the anti-breaking shaft to avoid damage to the output shaft. At this time, only the anti-breaking shaft needs to be replaced to put it into use again. However, the pneumatic actuator for the valve is not designed to adapt to higher connection components and cannot be widely used. In addition, the pneumatic actuator for the valve is not designed with a quick disassembly and assembly structure of the tooth block. After long-term use, the tooth block will wear out, affecting the normal operation of the pneumatic actuator, and the practicality is low. Utility Model Content

[0004] The purpose of the utility model is to provide a pneumatic actuator for an angle-rotating valve, which can solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a pneumatic actuator for an angle rotary valve, comprising a shell and a connecting block, a connecting assembly is arranged at the bottom of the shell, a pipeline is arranged at the bottom of the connecting assembly, a groove 2 is opened on the left side of the shell, a threaded hole 1 is opened on both the left and right sides of the shell, a groove 3 is opened on the top of the shell, a limit screw is connected to the front side of the shell by thread, a baffle 1 is arranged on the outside of the connecting block, the cross section of the baffle 1 is an "L"-shaped structure, a sleeve is arranged inside the connecting assembly, and a groove 6 and a threaded hole 4 are opened on the bottom of the shell;

[0006] The connecting assembly includes a connecting plate, a groove, a bolt, and a waist hole. A connecting plate is provided at the bottom of the shell, a groove is provided at the top of the connecting plate, a bolt is threadedly connected to the bottom of the connecting plate, and waist holes are provided on both sides of the connecting plate.

[0007] Preferably, a cover plate is provided on both the left and right sides of the shell, the outer side of the cover plate is threadedly connected with bolts four, the outer side of the cover plate is fixedly installed with a protrusion one, the outer side of the protrusion one is fixedly installed with a spring, the outer side of the spring is fixedly installed with a connecting block, the outer side of the connecting block is provided with a groove four, the inside of the groove four is provided with a rubber ring, the outer side of the connecting block is provided with a limiting groove and two threaded holes, the outer side of the baffle one is fixedly installed with a tooth block, the outer side of the baffle one is threadedly connected with bolts five, the outer side of the baffle one is fixedly installed with a limiting plate, the inside of the groove two is provided with a rotating shaft one, the outer side of the rotating shaft one is fixedly installed with a tooth ring and a limiting block, and a plurality of rubber rings of the same specification are provided, and the plurality of rubber rings are evenly distributed on the connecting block.

[0008] Preferably, the baffle plate 1 and the connecting block are installed by plugging through a limiting plate and a limiting groove, the bolt 5 penetrates the baffle plate 1 and extends to the inside of the threaded hole 2, and the cross-section of the baffle plate 1 is an "L"-shaped structure.

[0009] Preferably, the tooth blocks are provided with a plurality of the same specifications, the plurality of tooth blocks are evenly distributed on baffle 1, and the tooth blocks and the gear ring are meshingly connected.

[0010] Preferably, a protrusion 2 is fixedly installed on the bottom of the rotating shaft 1, a groove 5 and a threaded hole 3 are opened on the top of the pipe, a rotating shaft 2 is arranged inside the pipe, a protrusion 3 is fixedly installed on the top of the rotating shaft 2, a baffle 2 is fixedly installed on the outer side of the rotating shaft 2, and a connecting sleeve is arranged on the top of the protrusion 3, the center lines of the rotating shaft 1, the rotating shaft 2, the protrusion 2, the protrusion 3 and the connecting sleeve are located on the same vertical line, the connecting sleeve matches the protrusion 2, and the connecting sleeve matches the protrusion 3.

[0011] Preferably, the connecting assembly also includes a guide groove, a connecting plate 2, a bolt 2, a guide plate, a waist hole 2, a bolt 3 and a groove 7. A guide groove is provided at the bottom of the connecting plate 1, a connecting plate 2 is provided at the bottom of the connecting plate 1, a bolt 2 is threadedly connected to the bottom of the connecting plate 2, a guide plate is fixedly installed at the top of the connecting plate 2, a waist hole 2 is provided on the outer side of the guide plate, a bolt 3 is threadedly connected to the outer side of the connecting plate 1, a groove 7 is provided on the top of the connecting plate 2, the connecting plate 1 and the connecting plate 2 are plugged and installed through the guide plate and the guide groove, a plurality of waist holes 1 and waist holes 2 are provided with the same specifications, a plurality of waist holes 1 are evenly distributed on the connecting plate 1, a plurality of waist holes 2 are evenly distributed on the connecting plate 2, and the waist holes 1 and waist holes 2 are adapted to each other.

[0012] Preferably, an air hole is opened on the front side of the shell, and an installer is fixedly installed on the front side of the shell, a filter is arranged inside the installer, and two identical air holes are arranged, and the two air holes are symmetrically distributed about the center line of the shell, and the center lines of the air hole, the installer and the filter are located on the same vertical line.

[0013] Compared with the prior art, the beneficial effects of the utility model are:

[0014] 1. The utility model provides a guide plate and a guide groove. The staff inserts the guide plate into the guide groove, aligns the waist hole 1 with the waist hole 2, and then fixes them with bolts 3. The design of multiple waist holes 1 and waist holes 2 achieves an adjustable effect, thereby improving the adaptability of the connection assembly.

[0015] 2. The utility model provides a filter screen, through which the gas enters the interior of the housing, and the filter screen filters the dust in the gas, thereby preventing the accumulation of dust inside the housing due to the absence of a gas filtering mechanism, thereby affecting the normal operation of the pneumatic actuator;

[0016] 3. The utility model provides a limit plate and a limit groove. The staff will align the limit plate on the baffle plate 1 with the limit groove on the connecting block and insert it, and fix it with bolt 5, which is convenient for subsequent maintenance and repair. The bolt 5 plays a fixing role to avoid wear of the tooth block after long-term use, which affects the normal operation of the pneumatic actuator. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the three-dimensional structure of the utility model;

[0018] Figure 2 This is a schematic diagram of the split structure of the utility model Figure 1 ;

[0019] Figure 3 This is a schematic diagram of the split structure of the utility model Figure 2 ;

[0020] Figure 4 This is a schematic diagram of the split structure of the utility model Figure 3 ;

[0021] Figure 5 This is a schematic diagram of the split structure of the utility model Figure 4 ;

[0022] Figure 6 This is a schematic diagram of the split structure of the utility model Figure 5 ;

[0023] Figure 7 It is a schematic diagram of the three-dimensional structure of the shell of the utility model.

[0024] Among them: 1. Shell; 2. Connection assembly; 201. Connection plate 1; 202. Groove 1; 203. Bolt 1; 204. Waist hole 1; 205. Guide groove; 206. Connection plate 2; 207. Bolt 2; 208. Guide plate; 209. Waist hole 2; 210. Bolt 3; 211. Groove 7; 3. Pipe; 4. Groove 2; 5. Threaded hole 1; 6. Groove 3; 7. Limit screw; 8. Air hole; 9. Installer; 10. Filter; 11. Cover plate; 12. Bolt 4; 13. Bump 1; 14. Spring; 15. Connecting block; 16. Groove 4; 17. Rubber ring; 18. Limiting groove; 19. Threaded hole 2; 20. Baffle 1; 21. Tooth block; 22. Bolt 5; 23. Limiting plate; 24. Rotating shaft 1; 25. Tooth ring; 26. Limiting block; 27. Bump 2; 28. Groove 5; 29. ​​Threaded hole 3; 30. Rotating shaft 2; 31. Bump 3; 32. Baffle 2; 33. Connecting sleeve; 34. Sleeve; 35. Groove 6; 36. Threaded hole 4. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] Example 1

[0027] See also Figure 1-7 , a pneumatic actuator for an angle rotary valve shown in the figure comprises a housing 1 and a connecting block 15, a connecting assembly 2 is provided at the bottom of the housing 1, a pipe 3 is provided at the bottom of the connecting assembly 2, a groove 2 4 is provided on the left side of the housing 1, a threaded hole 1 5 is provided on both the left and right sides of the housing 1, a groove 3 6 is provided on the top of the housing 1, a limit screw 7 is threadedly connected to the front side of the housing 1, a baffle 1 20 is provided on the outside of the connecting block 15, and the cross section of the baffle 1 20 is an "L"-shaped structure, a sleeve 34 is provided inside the connecting assembly 2, and a groove 6 35 and a threaded hole 4 36 are provided at the bottom of the housing 1;

[0028] The connecting assembly 2 includes a connecting plate 201, a groove 202, a bolt 203, and a waist hole 204. A connecting plate 201 is arranged at the bottom of the shell 1, a groove 202 is provided at the top of the connecting plate 201, a bolt 203 is threadedly connected to the bottom of the connecting plate 201, and waist holes 204 are provided on both sides of the left and right sides of the connecting plate 201.

[0029] See also Figure 2-3In the figure, cover plates 11 are provided on both sides of the left and right sides of the shell 1, and bolts 12 are threadedly connected to the outer side of the cover plate 11, a protrusion 13 is fixedly installed on the outer side of the cover plate 11, a spring 14 is fixedly installed on the outer side of the protrusion 13, a connecting block 15 is fixedly installed on the outer side of the spring 14, a groove 16 is provided on the outer side of the connecting block 15, a rubber ring 17 is provided inside the groove 16, a limiting groove 18 and a threaded hole 19 are provided on the outer side of the connecting block 15, a tooth block 21 is fixedly installed on the outer side of the baffle 120, a bolt 5 22 is threadedly connected to the outer side of the baffle 120, a limiting plate 23 is fixedly installed on the outer side of the baffle 120, a rotating shaft 24 is provided inside the groove 24, a tooth ring 25 and a limiting block 26 are fixedly installed on the outer side of the rotating shaft 24, and a plurality of rubber rings 17 of the same specification are provided, and the plurality of rubber rings 17 are evenly distributed on the connecting block 15.

[0030] In this embodiment: by setting the rubber ring 17, the staff puts the rubber ring 17 into the groove 16, and the rubber ring 17 plays a sealing role. The design of multiple rubber rings 17 further improves the sealing effect, avoids poor sealing, causes air pressure loss, and affects the normal operation of the pneumatic actuator.

[0031] Working principle: During installation, the staff will align the limit plate 23 on the baffle 1 20 with the limit groove 18 on the connecting block 15 and insert it, and fix it with bolt 5 22, which is convenient for subsequent maintenance and repair. Bolt 5 22 plays a fixing role. The staff will insert the guide plate 208 into the guide groove 205, and then align the waist hole 1 204 and the waist hole 209, and then fix it with bolt 3 210. Through the design of multiple waist holes 1 204 and waist holes 209, an adjustable effect is achieved, which improves the adaptability of the connecting component 2. When in use, the gas enters the interior of the shell 1 through the filter 10, and the filter 10 filters the dust in the gas to avoid the absence of a gas filtering mechanism, which leads to dust accumulation inside the shell 1 and affects the normal operation of the pneumatic actuator. After the gas enters the interior of the shell 1, the air pressure inside the groove 2 4 Increase, the spring 14 is squeezed by force, so that the tooth block 21 moves, and drives the tooth ring 25 to rotate. Through the meshing method, the stability and working efficiency of the mechanical device can be increased. The rotation of the tooth ring 25 drives the rotation of the shaft 1 24. The shaft 1 24 and the shaft 2 30 are connected through the provided connecting sleeve 33. The shaft 1 24 rotates, driving the shaft 2 30 to rotate, so that the baffle 2 32 rotates, so as to achieve the effect of controlling the internal flow of the valve. At the same time, the rubber ring 17 plays a sealing role. The design of multiple rubber rings 17 further improves the sealing effect, avoids poor sealing, resulting in air pressure loss, and affects the normal operation of the pneumatic actuator. After a long period of use, the tooth block 21 will be worn, and the baffle 1 20 can be replaced to avoid the tooth block 21 being worn after a long period of use, which affects the normal operation of the pneumatic actuator.

[0032] Example 2

[0033] See also Figure 2-3 This embodiment further explains Example 1. In the figure, baffle plate 1 20 and connecting block 15 are plugged and installed through limiting plate 23 and limiting groove 18. Bolt 5 22 penetrates baffle plate 1 20 and extends to the inside of threaded hole 2 19. The cross section of baffle plate 1 20 is an "L"-shaped structure.

[0034] In this embodiment: by setting the limit plate 23 and the limit groove 18, the staff will align the limit plate 23 on the baffle 1 20 with the limit groove 18 on the connecting block 15 and insert it, and fix it with the bolt 5 22, which is convenient for subsequent maintenance and repair. The bolt 5 22 plays a fixing role to avoid the tooth block 21 from being worn after long-term use, which affects the normal operation of the pneumatic actuator.

[0035] See also Figure 2-3 In the figure, a plurality of gear blocks 21 of the same specification are provided, and the plurality of gear blocks 21 are evenly distributed on the baffle 1 20 , and the gear blocks 21 and the gear ring 25 are meshingly connected.

[0036] In this embodiment: by cooperating with the tooth block 21 and the tooth ring 25, the gas enters the interior of the groove 2 4 from the air hole 8, and then the air pressure inside the groove 2 4 increases, and the spring 14 is squeezed by force, so that the tooth block 21 moves, driving the tooth ring 25 to rotate, and the stability and working efficiency of the mechanical device can be increased by meshing.

[0037] See also Figure 6 In the figure, a protrusion 27 is fixedly installed at the bottom of the rotating shaft 1 24, a groove 5 28 and a threaded hole 3 29 are opened on the top of the pipe 3, a rotating shaft 2 30 is arranged inside the pipe 3, a protrusion 31 is fixedly installed on the top of the rotating shaft 2 30, a baffle 2 32 is fixedly installed on the outer side of the rotating shaft 2 30, and a connecting sleeve 33 is arranged on the top of the protrusion 31. The center lines of the rotating shaft 1 24, the rotating shaft 2 30, the protrusion 27, the protrusion 31 and the connecting sleeve 33 are located on the same vertical line, the connecting sleeve 33 matches the protrusion 2 27, and the connecting sleeve 33 matches the protrusion 31.

[0038] In this embodiment, the connecting sleeve 33 is provided to connect the rotating shaft 1 24 and the rotating shaft 2 30 . The rotating shaft 1 24 rotates, driving the rotating shaft 2 30 to rotate, causing the baffle 2 32 to rotate, thereby achieving the effect of controlling the flow inside the valve.

[0039] See also Figure 4In the figure, the connecting assembly 2 also includes a guide groove 205, a second connecting plate 206, a second bolt 207, a guide plate 208, a second waist hole 209, a third bolt 210 and a seventh groove 211. The bottom of the connecting plate 1 201 is provided with a guide groove 205, the bottom of the connecting plate 1 201 is provided with a second connecting plate 206, the bottom of the connecting plate 206 is threadedly connected with a second bolt 207, the top of the connecting plate 206 is fixedly installed with a guide plate 208, and the outer side of the guide plate 208 is provided with a second waist hole 209. 9. The outer side of the connecting plate 1 201 is threadedly connected with a bolt 3 210, and a groove 7 211 is provided on the top of the connecting plate 206. The connecting plate 1 201 and the connecting plate 206 are plugged and installed through the guide plate 208 and the guide groove 205. The waist hole 1 204 and the waist hole 2 209 are provided with multiple waist holes of the same specification. The multiple waist holes 1 204 are evenly distributed on the connecting plate 1 201, and the multiple waist holes 209 are evenly distributed on the connecting plate 2 206. The waist holes 1 204 and the waist holes 2 209 are adapted to each other.

[0040] In this embodiment: by setting the guide plate 208 and the guide groove 205, the staff inserts the guide plate 208 into the guide groove 205, and then aligns the waist hole 1 204 and the waist hole 209, and then fixes them by the bolt 3 210. Through the design of multiple waist holes 1 204 and waist holes 2 209, an adjustable effect is achieved, thereby improving the adaptability of the connecting component 2.

[0041] See also Figure 1-2 and Figure 7 In the figure, an air hole 8 is opened on the front side of the shell 1, and a mounter 9 is fixedly installed on the front side of the shell 1. A filter 10 is arranged inside the mounter 9. Two identical air holes 8 are arranged, and the two air holes 8 are symmetrically distributed about the center line of the shell 1. The center lines of the air holes 8, the mounter 9 and the filter 10 are located on the same vertical line.

[0042] In this embodiment: through the filter 10 that is set, the gas enters the interior of the shell 1 through the filter 10, and the filter 10 filters the dust in the gas to avoid the lack of a gas filtering mechanism, which leads to dust accumulation inside the shell 1 and affects the normal operation of the pneumatic actuator.

[0043] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include"-"comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process-method-article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process-method-article or device.

[0044] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A pneumatic actuator for an angle-rotating valve, comprising a housing (1) and a connecting block (15), characterized in that: A connecting assembly (2) is provided at the bottom of the shell (1), a pipe (3) is provided at the bottom of the connecting assembly (2), a groove (2) (4) is provided on the left side of the shell (1), a threaded hole (5) is provided on both the left and right sides of the shell (1), a groove (3) (6) is provided on the top of the shell (1), a limit screw (7) is threadedly connected to the front side of the shell (1), a baffle (20) is provided on the outside of the connecting block (15), and the cross section of the baffle (20) is in an "L"-shaped structure, a sleeve (34) is provided inside the connecting assembly (2), and a groove (6) (35) and a threaded hole (4) (36) are provided at the bottom of the shell (1); The connecting assembly (2) comprises a connecting plate (201), a groove (202), a bolt (203), and a waist hole (204); the bottom of the shell (1) is provided with a connecting plate (201); the top of the connecting plate (201) is provided with a groove (202); the bottom of the connecting plate (201) is threadedly connected with a bolt (203); and waist holes (204) are provided on both left and right sides of the connecting plate (201).

2. A pneumatic actuator for an angle-rotating valve according to claim 1, characterized in that: The left and right sides of the shell (1) are both provided with a cover plate (11), the outer side of the cover plate (11) is threadedly connected with a bolt four (12), the outer side of the cover plate (11) is fixedly mounted with a protrusion one (13), the outer side of the protrusion one (13) is fixedly mounted with a spring (14), the outer side of the spring (14) is fixedly mounted with a connecting block (15), the outer side of the connecting block (15) is provided with a groove four (16), the interior of the groove four (16) is provided with a rubber ring (17), the outer side of the connecting block (15) is provided with a limiting groove (1 8) and threaded hole two (19), a tooth block (21) is fixedly installed on the outer side of the baffle one (20), a bolt five (22) is threadedly connected to the outer side of the baffle one (20), a limit plate (23) is fixedly installed on the outer side of the baffle one (20), a rotating shaft one (24) is arranged inside the groove two (4), a tooth ring (25) and a limit block (26) are fixedly installed on the outer side of the rotating shaft one (24), and a plurality of rubber rings (17) of the same specification are arranged, and the plurality of rubber rings (17) are evenly distributed on the connecting block (15).

3. A pneumatic actuator for an angle-rotating valve according to claim 2, characterized in that: The baffle plate 1 (20) and the connecting block (15) are plugged and installed through the limiting plate (23) and the limiting groove (18), and the bolt 5 (22) penetrates the baffle plate 1 (20) and extends to the inside of the threaded hole 2 (19).

4. A pneumatic actuator for an angle-rotating valve according to claim 2, characterized in that: The tooth blocks (21) are provided in plurality with the same specifications, and the plurality of tooth blocks (21) are evenly distributed on the baffle plate 1 (20), and the tooth blocks (21) and the gear ring (25) are meshingly connected.

5. A pneumatic actuator for an angle-rotating valve according to claim 2, characterized in that: A second protrusion (27) is fixedly mounted on the bottom of the rotating shaft (24), a fifth groove (28) and a third threaded hole (29) are provided on the top of the pipe (3), a second rotating shaft (30) is arranged inside the pipe (3), a third protrusion (31) is fixedly mounted on the top of the second rotating shaft (30), a second baffle (32) is fixedly mounted on the outer side of the second rotating shaft (30), a connecting sleeve (33) is arranged on the top of the third protrusion (31), the center lines of the first rotating shaft (24), the second rotating shaft (30), the second protrusion (27), the third protrusion (31) and the connecting sleeve (33) are located on the same vertical line, the connecting sleeve (33) matches the second protrusion (27), and the connecting sleeve (33) matches the third protrusion (31).

6. A pneumatic actuator for an angle-rotating valve according to claim 1, characterized in that: The connection assembly (2) further comprises a guide groove (205), a second connection plate (206), a second bolt (207), a guide plate (208), a second waist hole (209), a third bolt (210) and a seventh groove (211); the guide groove (205) is provided at the bottom of the first connection plate (201); the second connection plate (206) is provided at the bottom of the first connection plate (201); the second bolt (207) is threadedly connected to the bottom of the second connection plate (206); the guide plate (208) is fixedly mounted on the top of the second connection plate (206); and the second waist hole (209) is provided on the outer side of the guide plate (208). The outer side of the connecting plate 1 (201) is threadedly connected with a bolt 3 (210), the top of the connecting plate 2 (206) is provided with a groove 7 (211), the connecting plate 1 (201) and the connecting plate 2 (206) are plugged and installed through a guide plate (208) and a guide groove (205), and the waist hole 1 (204) and the waist hole 2 (209) are provided with multiple waist holes of the same specification, and the multiple waist holes 1 (204) are evenly distributed on the connecting plate 1 (201), and the multiple waist holes 2 (209) are evenly distributed on the connecting plate 2 (206), and the waist holes 1 (204) and the waist holes 2 (209) are adapted to each other.

7. A pneumatic actuator for an angle-rotating valve according to claim 1, characterized in that: The front side of the shell (1) is provided with an air hole (8), the front side of the shell (1) is fixedly installed with a mounter (9), the interior of the mounter (9) is provided with a filter screen (10), two identical air holes (8) are provided, the two air holes (8) are symmetrically distributed about the center line of the shell (1), and the center lines of the air hole (8), the mounter (9) and the filter screen (10) are located on the same vertical line.

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