High-precision pressure control device of gluing machine

Abstract

The utility model relates to the field of gluing machines, in particular to a high-precision gluing machine pressure control device which comprises a bypass pipe arranged on a glue pipe in a communicating mode, two ports of the bypass pipe are formed in the two sides of a quantitative gear pump respectively, and a pneumatic shuttle valve is installed on the bypass pipe. An air inlet end of the pneumatic shuttle valve is communicated with an air inlet control module for providing different air pressures for the pneumatic shuttle valve, and the air inlet control module is in signal connection with a signal output end of a control module of the gluing machine; and an air source filtering module is detachably mounted at the air inlet end of the air inlet control module. The glue outlet stability can be improved when the glue gun sprays glue.

Description

Technical Field

[0001] The present application relates to the field of glue coating machines, and in particular to a high-precision pressure control device for glue coating machines. Background Art

[0002] Hot melt adhesive machines are widely used in the home appliance industry, automotive industry, filter industry, bottle cap bonding industry, non-woven fabric industry, packaging industry, packaging label industry, footwear industry, medical dressing industry and clothing material composite industry.

[0003] In the prior art, the automatic gluing system of a common hot melt glue coating machine is mainly composed of a control module, a metering gear pump, a hose, a glue gun, etc. The glue gun is fixedly installed on the frame of the hot melt glue coating machine, the hose connects the glue gun and the hot melt glue supply mechanism, the metering gear pump is installed on the hose, and the glue gun is installed with a glue solenoid valve for controlling the opening or closing of the glue gun. The signal output end of the control module is connected to the signal input end of the metering gear pump. The operator can input a start control signal or a close control signal through the control module, and the signal input end of the glue solenoid valve is connected to the signal output end of the control module. After receiving the start control signal, the glue solenoid valve controls the glue gun to flow out the glue. After receiving the close control signal, the glue solenoid valve controls the glue gun to stop flowing out the glue.

[0004] Among them, in order to avoid the situation where the colloid pressure in the hose gradually increases due to the closing of the glue gun and the continuous rotation of the quantitative gear pump, a bypass pipe is often installed on the hose, and a reflux valve is installed on the bypass pipe. The two ends of the bypass pipe are respectively connected to the two sides of the quantitative gear pump. The operator can preset the threshold pressure of the reflux valve according to actual use needs. When the solenoid valve is closed and the colloid pressure in the hose gradually increases to exceed the threshold pressure, the reflux valve is connected to the bypass pipe, and the colloid flows back from the bypass pipe to the glue inlet end of the quantitative gear pump, which can reduce the pressure in the hose between the glue outlet end of the quantitative gear pump and the glue gun, thereby maintaining the stability of the hose pressure.

[0005] However, the set pressure of the reflux valve is greater than the working pressure of the glue gun. The glue pressure in the hose is relatively high during the closing process of the solenoid valve, which can easily lead to excessive glue pressure for a period of time after the solenoid valve is opened, and excessive glue flowing out of the glue gun. It will take a period of time to stabilize, resulting in uneven glue volume at the front and back. Utility Model Content

[0006] In order to improve the stability of glue discharge when a glue gun sprays colloid, the present application provides a high-precision glue coating machine pressure control device.

[0007] The application provides a high-precision glue coating machine pressure control device adopts the following technical solutions:

[0008] A high-precision glue coating machine pressure control device includes a bypass pipe connected to a rubber hose, the two ports of the bypass pipe are respectively arranged on both sides of a quantitative gear pump, a pneumatic shuttle valve is installed on the bypass pipe, the air inlet end of the pneumatic shuttle valve is connected to an air intake control module for providing different air pressures to the pneumatic shuttle valve, and the air intake control module is signal-connected to the signal output end of the control module of the glue coating machine;

[0009] An air source filter module is detachably mounted on the air intake end of the air intake control module.

[0010] By adopting the above technical solution, during the actual gluing process, the control module controls the opening or closing of the gluing solenoid valve on the gluing gun, and can synchronously control the air intake control module to adjust the air source pressure input to the pneumatic shuttle valve. When the gluing solenoid valve is started, the air intake control module controls the air source pressure input to the pneumatic shuttle valve to be larger, and the valve core of the pneumatic shuttle valve descends, so that the colloid flow in the bypass pipe is reduced, and the bypass pipe is reduced to the colloid in the hose, which can ensure uniform and stable glue discharge from the hose; when the gluing solenoid valve is closed, the air intake control module controls the air source pressure input to the pneumatic shuttle valve to be smaller, and the valve core of the pneumatic shuttle valve rises, so that the colloid flow in the bypass pipe is increased, and the bypass pipe is increased to the colloid in the hose. The colloid delivered by the quantitative gear pump can be returned to the front end of the quantitative gear pump through the bypass pipe, so as to avoid the colloid pressure in the hose being too high, so that the gluing gun discharges too much glue when it is reopened, and the stability of the glue discharge amount of the gluing gun can be effectively guaranteed. In addition, by setting up the air source filtration module, the air source input to the pneumatic shuttle valve can be purified and filtered, reducing the occurrence of dust in the workshop air entering the pneumatic shuttle valve and causing adverse effects on the pneumatic shuttle valve.

[0011] Preferably, the air intake control module includes an air intake pipe, an electric three-way valve, a first branch pipe, and a second branch pipe. The air outlet end of the air intake pipe is connected to the air intake end of the electric three-way valve. The air source filter module is detachably mounted on the air intake end of the first branch pipe. The two air outlet ends of the electric three-way valve are respectively connected to the air intake ends of the first branch pipe and the second branch pipe. The air outlet ends of the first branch pipe and the second branch pipe are connected to the air intake end of the pneumatic shuttle valve.

[0012] A first air intake control unit is installed on the first branch pipe, and a second air intake control unit is installed on the second branch pipe. The signal input ends of the first air intake control unit, the second air intake control unit and the electric three-way valve are signal-connected to the signal output end of the control module.

[0013] The electric three-way valve receives a start control signal and connects the first branch pipe and closes the second branch pipe, and the electric three-way valve receives a close control signal and connects the second branch pipe;

[0014] The first air intake control unit receives a start control signal and provides an air source of a first air pressure to the pneumatic shuttle valve, and the first air intake control unit receives a close control signal and closes;

[0015] The second air intake control unit receives a start control signal and is turned off. The second air intake control unit receives a stop control signal and provides an air source of a second air pressure to the pneumatic shuttle valve.

[0016] By adopting the above technical solution, when the gluing solenoid valve is started, the electric three-way valve connects the air intake pipe and the first branch pipe, and the first air intake control unit can provide a gas source with a higher air pressure to the pneumatic shuttle valve, so that the bypass pipe is closed, thereby ensuring that the pressure of the colloid in the hose remains stable; when the gluing solenoid valve is closed, the electric three-way valve connects the air intake pipe and the second branch pipe, the first air intake control unit is closed, and the second air intake control unit provides a gas source with a lower air pressure to the pneumatic shuttle valve, so that the bypass pipe is opened, and the colloid in the hose flows back to the front end of the quantitative gear pump through the bypass pipe, which can prevent the colloid pressure in the hose from being too high, resulting in excessive glue output from the gluing gun when the gluing gun is reopened.

[0017] Preferably, the first air intake control unit includes an air intake solenoid valve installed on the first branch pipe, and a signal input end of the air intake solenoid valve is signal-connected to a signal output end of the control module.

[0018] By adopting the above technical solution, the electric three-way valve and the air inlet solenoid valve are used in combination with each other to achieve the switching of higher pressure air sources, and the pneumatic shuttle valve can be controlled to shut off the bypass pipe when the glue gun is started, so as to prevent the colloid in the hose from flowing back through the bypass pipe, thereby maintaining the colloid pressure in the hose stable.

[0019] Preferably, the second air intake control unit includes a high-precision pressure regulating valve installed on the second branch pipe, and the signal input end of the high-precision pressure regulating valve is signal-connected to the signal output end of the control module.

[0020] By adopting the above technical solution, the electric three-way valve and the high-precision pressure regulating valve are used in combination to achieve the switching of the lower pressure air source, and the pneumatic shuttle valve can be controlled to connect to the bypass pipe when the glue gun is closed, so that the colloid output by the quantitative gear pump can be returned to the front end of the quantitative gear pump, avoiding the situation where the colloid pressure in the hose is too high and the glue output is too much in the early stage of opening the glue gun.

[0021] Preferably, the air source filter module includes an air filter box, and the air filter box is detachably mounted on the air inlet end of the air inlet pipe;

[0022] The air inlet end of the air filter box is threadedly connected to a sealing cover, and both the sealing cover and the air filter box are provided with through holes for the external air source to flow through, and the two through holes are directly opposite to the pipe opening of the air inlet pipe;

[0023] An installation cavity is formed in the air filter box, and activated carbon and two porcelain plates are installed in the installation cavity. A plurality of air holes are respectively opened on the two porcelain plates, and the activated carbon is sandwiched between the two porcelain plates.

[0024] By adopting the above technical solution, the activated carbon in the air filter box can filter the air source, reducing the possibility of dust and moisture carried by the air source entering the pneumatic shuttle valve. The air filter box can be removably installed at the air inlet end of the air inlet pipe, making it easy for operators to regularly remove the air filter box and replace and clean the activated carbon and porcelain plate inside the air filter box.

[0025] Preferably, an external thread is provided on the outside of the air inlet end of the air inlet pipe, and the air filter box includes a connecting end with a mounting screw hole provided therein, and the connecting end is threadedly mounted on the air inlet end of the air inlet pipe.

[0026] By adopting the above technical solution, the mounting screw holes on the connecting end and the external threads at the air inlet end of the air inlet pipe are used in combination with each other, so as to achieve the technical effect of detachable connection between the air filter box and the air inlet pipe, making it easier for operators to disassemble the air filter box.

[0027] In summary, the present invention provides a glue coating platform for a glue roller machine, which has at least one of the following beneficial technical effects:

[0028] 1. During the actual gluing process, the control module controls the gluing solenoid valve on the gluing gun to be opened or closed, and at the same time, it can synchronously control the air intake control module to adjust the air source pressure input to the pneumatic shuttle valve. When the gluing solenoid valve is started, the air intake control module controls the air source pressure input to the pneumatic shuttle valve to be larger, and the valve core of the pneumatic shuttle valve descends, so that the colloid flow in the bypass pipe is reduced, and the shunt of the colloid in the hose by the bypass pipe is reduced, which can ensure uniform and stable glue discharge from the hose; when the gluing solenoid valve is closed, the air intake control module controls the air source pressure input to the pneumatic shuttle valve to be smaller, and the valve core of the pneumatic shuttle valve rises, so that the colloid flow in the bypass pipe is increased, and the shunt of the colloid in the hose by the bypass pipe is increased, which can make the colloid delivered by the quantitative gear pump flow back to the front end of the quantitative gear pump through the bypass pipe, so as to avoid the colloid pressure in the hose being too high, so that the gluing gun discharges too much glue when it is reopened, and can effectively ensure the stability of the glue discharge amount of the gluing gun;

[0029] 2. The activated carbon in the air filter box can filter the air source, reducing the possibility of dust and moisture carried in the air source entering the pneumatic shuttle valve. The air filter box can be removably installed at the air inlet end of the air inlet pipe, allowing operators to regularly remove the air filter box and replace and clean the activated carbon and porcelain plate inside the air filter box. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1It is a schematic diagram used to illustrate the overall structure of the pressure control device in the embodiment of the present application.

[0031] Figure 2 This is a schematic diagram used to illustrate the internal signal transmission of the pressure control device in an embodiment of the present application.

[0032] Figure 3 It is a schematic diagram used to illustrate the internal structure of the air filter box in an embodiment of the present application.

[0033] Explanation of the accompanying symbols: 1. Hose; 2. Bypass pipe; 3. Dosing gear pump; 4. Intake control module; 41. Intake pipe; 42. Electric three-way valve; 43. First branch pipe; 44. Second branch pipe; 45. Intake solenoid valve; 46. High-precision pressure regulating valve; 47. Pneumatic shuttle valve; 5. Air source filter module; 51. Air filter box; 52. Sealing cover; 53. Installation cavity; 54. Ceramic plate; 55. Activated carbon; 56. Connection end; 561. Installation screw hole; 6. Glue gun. DETAILED DESCRIPTION

[0034] The following is combined with Figure 1-2 This application is described in further detail.

[0035] Example

[0036] The embodiment of the present application discloses a high-precision pressure control device for a glue coating machine. Figure 1-Figure 3 , including a bypass pipe 2 connected to the hose 1, the two ports of the bypass pipe 2 are respectively arranged on both sides of the quantitative gear pump 3, a pneumatic shuttle valve 47 is installed on the bypass pipe 2, and the air inlet end of the pneumatic shuttle valve 47 is connected to an air intake control module 4 for providing different air pressures to the pneumatic shuttle valve 47, and the air intake control module 4 is connected to the signal output end of the control module of the glue coating machine; the air intake end of the air intake control module 4 is detachably installed with an air source filter module 5.

[0037] During the actual gluing process, the control module controls the opening or closing of the gluing solenoid valve on the gluing gun 6, and at the same time, it can synchronously control the air intake control module 4 to adjust the air source pressure input to the pneumatic shuttle valve 47. When the gluing solenoid valve is started, the air intake control module 4 controls the air source pressure input to the pneumatic shuttle valve 47 to be relatively high, and the valve core of the pneumatic shuttle valve 47 drops, so that the colloid flow in the bypass pipe 2 is reduced, reducing the diversion of the colloid in the hose 1 by the bypass pipe 2, which can ensure uniform and stable glue discharge from the hose 1; when When the glue solenoid valve is closed, the air intake control module 4 controls the air source pressure of the input pneumatic shuttle valve 47 to be relatively low, and the valve core of the pneumatic shuttle valve 47 rises, thereby increasing the flow rate of the colloid in the bypass pipe 2, increasing the diversion of the colloid in the hose 1 by the bypass pipe 2, and allowing the colloid delivered by the quantitative gear pump 3 to flow back to the front end of the quantitative gear pump 3 through the bypass pipe 2, thereby preventing the colloid pressure in the hose 1 from being too high, resulting in excessive glue discharge from the glue gun 6 when it is reopened, and effectively ensuring the stability of the glue discharge amount of the glue gun 6.

[0038] In addition, by providing the air source filter module 5 , the air source input to the pneumatic shuttle valve 47 can be purified and filtered, thereby reducing the possibility of dust in the workshop air entering the pneumatic shuttle valve 47 and causing adverse effects on the pneumatic shuttle valve 47 .

[0039] Reference Figure 1 、 Figure 2 as well as Figure 3 The air intake control module 4 includes an air intake pipe 41, an electric three-way valve 42, a first branch pipe 43 and a second branch pipe 44. The air outlet end of the air intake pipe 41 is connected to the air inlet end of the electric three-way valve 42. The air source filter module 5 can be detachably installed on the air inlet end of the first branch pipe 43. The two air outlet ends of the electric three-way valve 42 are respectively connected to the air inlet ends of the first branch pipe 43 and the second branch pipe 44. The air outlet ends of the first branch pipe 43 and the second branch pipe 44 are connected to the air inlet end of the pneumatic shuttle valve 47.

[0040] A first air intake control unit is installed on the first branch pipe 43, and a second air intake control unit is installed on the second branch pipe 44. The signal input ends of the first air intake control unit, the second air intake control unit and the electric three-way valve 42 are signal-connected to the signal output end of the control module.

[0041] The electric three-way valve 42 receives a start control signal and connects the first branch pipe 43 and closes the second branch pipe 44 . The electric three-way valve 42 receives a close control signal and connects the second branch pipe 44 .

[0042] The first air intake control unit receives a start control signal and provides an air source of a first air pressure to the pneumatic shuttle valve 47 . The first air intake control unit receives a close control signal and closes.

[0043] The second air intake control unit receives the start control signal and is closed. The second air intake control unit receives the close control signal and provides an air source of the second air pressure to the pneumatic shuttle valve 47 .

[0044] When the glue coating solenoid valve is started, the electric three-way valve 42 connects the air intake pipe 41 and the first branch pipe 43, and the first air intake control unit can provide a gas source with a higher air pressure to the pneumatic shuttle valve 47, so that the bypass pipe 2 is closed, ensuring that the pressure of the colloid in the hose 1 remains stable; when the glue coating solenoid valve is closed, the electric three-way valve 42 connects the air intake pipe 41 and the second branch pipe 44, the first air intake control unit is closed, and the second air intake control unit provides a gas source with a lower air pressure to the pneumatic shuttle valve 47, so that the bypass pipe 2 is opened, and the colloid in the hose 1 flows back to the front end of the quantitative gear pump 3 through the bypass pipe 2, which can prevent the colloid pressure in the hose 1 from being too high, causing the glue gun 6 to output too much glue when it is reopened.

[0045] Reference Figure 1 and Figure 2 The first air intake control unit includes an air intake solenoid valve 45 installed on the first branch pipe 43, and the signal input end of the air intake solenoid valve 45 is signal-connected to the signal output end of the control module.

[0046] By using the electric three-way valve 42 and the air inlet solenoid valve 45 in combination with each other, it is possible to switch to a higher pressure air source, and the pneumatic shuttle valve 47 can be controlled to shut off the bypass pipe 2 when the glue gun 6 is started, so as to prevent the colloid in the hose 1 from flowing back through the bypass pipe 2, thereby keeping the colloid pressure in the hose 1 stable.

[0047] Reference Figure 1 and Figure 2 The second air intake control unit includes a high-precision pressure regulating valve 46 installed on the second branch pipe 44, and the signal input end of the high-precision pressure regulating valve 46 is signal-connected to the signal output end of the control module.

[0048] By using the electric three-way valve 42 and the high-precision pressure-regulating valve 46 in combination with each other, switching of a lower pressure air source can be achieved, and the pneumatic shuttle valve 47 can be controlled to connect to the bypass pipe 2 when the glue gun 6 is closed, so that the colloid output by the quantitative gear pump 3 can be returned to the front end of the quantitative gear pump 3, thereby preventing the colloid pressure in the hose 1 from being too high, which may cause excessive glue output in the early stage of opening the glue gun 6.

[0049] It should be noted that in the embodiment of the present application, when the glue gun 6 is working normally, the air inlet solenoid valve 45 supplies an air source pressure of 6 bar to the pneumatic shuttle valve 47; when the glue gun 6 is closed, the pressure regulating valve supplies an air source pressure of 2 bar to the pneumatic shuttle valve 47.

[0050] Reference Figure 3The air source filtration module 5 includes an air filter box 51, which can be detachably mounted on the air inlet end of the air inlet pipe 41; a cover 52 is threadedly connected to the air inlet end of the air filter box 51, and through holes for external air flow are provided on the cover 52 and the air filter box 51, and the two through holes are directly opposite to the pipe mouth of the air inlet pipe 41; an installation cavity 53 is formed in the air filter box 51, and activated carbon 55 and two porcelain plates 54 are installed in the installation cavity 53, and a number of air holes are respectively provided on the two porcelain plates 54, and the activated carbon 55 is sandwiched between the two porcelain plates 54.

[0051] The activated carbon 55 in the air filter box 51 can filter the air source, reducing the possibility of dust, moisture, etc. carried in the air source entering the pneumatic shuttle valve 47. The air filter box 51 can be detachably mounted at the air inlet end of the air inlet pipe 41, which makes it easy for operators to regularly remove the air filter box 51 and replace and clean the activated carbon 55, porcelain plate 54, etc. in the air filter box 51.

[0052] Among them, the outer side of the air intake end of the air intake pipe 41 is provided with an external thread, and the air filter box 51 includes a connecting end 56, and a mounting screw hole 561 is opened in the connecting end 56. The connecting end 56 is threadedly installed on the air intake end of the air intake pipe 41.

[0053] By using the mounting screw hole 561 on the connecting end 56 in combination with the external thread of the air inlet end of the air inlet pipe 41, the technical effect of a detachable connection between the air filter box 51 and the air inlet pipe 41 can be achieved, making it easier for the operator to disassemble the air filter box 51.

[0054] The implementation principle of a high-precision glue coating machine pressure control device in the embodiment of the present application is as follows: during the actual glue coating process, the control module controls the glue coating solenoid valve on the glue coating gun 6 to be opened or closed, and at the same time, the air intake control module 4 can be synchronously controlled to adjust the air source pressure input to the pneumatic shuttle valve 47. When the glue coating solenoid valve is started, the air intake control module 4 controls the air source pressure input to the pneumatic shuttle valve 47 to be relatively large, and the valve core of the pneumatic shuttle valve 47 drops, so that the colloid flow in the bypass pipe 2 is reduced, reducing the diversion of the colloid in the hose 1 by the bypass pipe 2, which can ensure the smooth flow of the glue coating machine. The glue hose 1 is prevented from discharging glue evenly and stably; when the glue solenoid valve is closed, the air intake control module 4 controls the air source pressure of the input pneumatic shuttle valve 47 to be relatively small, and the valve core of the pneumatic shuttle valve 47 rises, which increases the flow of the colloid in the bypass pipe 2, increases the diversion of the colloid in the hose 1 by the bypass pipe 2, and allows the colloid delivered by the quantitative gear pump 3 to flow back to the front end of the quantitative gear pump 3 through the bypass pipe 2, avoiding the situation where the colloid pressure in the hose 1 is too high and the glue gun 6 discharges too much glue when it is reopened, and can effectively ensure the stability of the glue output of the glue gun 6.

[0055] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A high-precision glue coating machine pressure control device, characterized in that: The invention comprises a bypass pipe (2) connected to a rubber hose (1), wherein two ports of the bypass pipe (2) are respectively arranged on both sides of a quantitative gear pump (3), a pneumatic shuttle valve (47) is installed on the bypass pipe (2), an air inlet end of the pneumatic shuttle valve (47) is connected to an air inlet control module (4) for providing different air pressures to the pneumatic shuttle valve (47), and the air inlet control module (4) is connected to a signal output end of a control module of a glue coating machine; An air source filter module (5) is detachably mounted on the air intake end of the air intake control module (4).

2. A high-precision glue coating machine pressure control device according to claim 1, characterized in that: The air intake control module (4) comprises an air intake pipe (41), an electric three-way valve (42), a first branch pipe (43) and a second branch pipe (44); the air outlet end of the air intake pipe (41) is connected to the air intake end of the electric three-way valve (42); the air source filter module (5) is detachably mounted on the air intake end of the first branch pipe (43); the two air outlet ends of the electric three-way valve (42) are respectively connected to the air intake ends of the first branch pipe (43) and the second branch pipe (44); the air outlet ends of the first branch pipe (43) and the second branch pipe (44) are connected to the air intake end of the pneumatic shuttle valve (47); A first air intake control unit is installed on the first branch pipe (43), a second air intake control unit is installed on the second branch pipe (44), and the signal input ends of the first air intake control unit, the second air intake control unit and the electric three-way valve (42) are connected to the signal output end of the control module; The electric three-way valve (42) receives a start control signal and connects the first branch pipe (43) and closes the second branch pipe (44); the electric three-way valve (42) receives a close control signal and connects the second branch pipe (44); The first air intake control unit receives a start control signal and provides an air source of a first air pressure to the pneumatic shuttle valve (47), and the first air intake control unit receives a close control signal and closes; The second air intake control unit receives a start control signal and is closed, and the second air intake control unit receives a close control signal and provides an air source of a second air pressure to the pneumatic shuttle valve (47).

3. A high-precision glue coating machine pressure control device according to claim 2, characterized in that: The first air intake control unit comprises an air intake solenoid valve (45) installed on the first branch pipe (43), and a signal input end of the air intake solenoid valve (45) is signal-connected to a signal output end of the control module.

4. A high-precision glue coating machine pressure control device according to claim 2, characterized in that: The second air intake control unit comprises a high-precision pressure regulating valve (46) installed on the second branch pipe (44), and a signal input end of the high-precision pressure regulating valve (46) is signal-connected to a signal output end of the control module.

5. A high-precision glue coating machine pressure control device according to claim 2, characterized in that: The air source filter module (5) comprises an air filter box (51), and the air filter box (51) is detachably mounted on the air inlet end of the air inlet pipe (41); The air inlet end of the air filter box (51) is threadedly connected to a sealing cover (52), and both the sealing cover (52) and the air filter box (51) are provided with through holes for the circulation of an external air source, and the two through holes are directly opposite to the pipe opening of the air inlet pipe (41); An installation cavity (53) is formed in the air filter box (51), and activated carbon (55) and two porcelain plates (54) are installed in the installation cavity (53). The two porcelain plates (54) are respectively provided with a plurality of air holes, and the activated carbon (55) is sandwiched between the two porcelain plates (54).

6. A high-precision glue coating machine pressure control device according to claim 5, characterized in that: The air inlet end of the air inlet pipe (41) is provided with an external thread on its outer side. The air filter box (51) includes a connecting end (56). A mounting screw hole (561) is provided in the connecting end (56). The connecting end (56) is threadedly mounted on the air inlet end of the air inlet pipe (41).

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