Comprehensive control system for high-precision quantitative powder conveying

Abstract

The invention relates to a comprehensive control system for high-precision quantitative powder conveying in the technical field of powder conveying. The comprehensive control system comprises an air pressure distribution control module, a pneumatic logic control module, a powder distribution valve module and a filter element module. The dense-phase conveying technology is adopted, and a series of problems of large gas consumption, high flow speed, unstable flow, low flow, frequent replacement of quick-wear parts, complex cleaning and the like of Venturi conveying are solved; due to the fact that retrograde double-channel double-outlet is adopted, each conveying pump can supply two spraying devices at the same time, more electronic elements such as a controller and an electromagnetic valve are not added, and the cost, the use space, the energy consumption and the like of the dense-phase pump are greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of powder conveying, and in particular to an integrated control system for accurately and quantitatively conveying powder. Background Art

[0002] The principle of electrostatic powder coating is that after the powder is fluidized, it is transported to the powder coating apparatus by a powder pump. The powder coating apparatus has a high-voltage power distribution function, and while atomizing, the powder is charged with high-voltage static electricity. For coating safety, generally, negative high-voltage spraying is used. The workpiece is grounded, and the powder with negative high-voltage static electricity is adsorbed onto the surface of the workpiece under the combined action of compressed air, electrostatic adsorption force, and high-voltage electrostatic field force, thereby completing the powder coating.

[0003] In the past, a venturi pump was generally used to transport powder. The working principle of the venturi pump is that after compressed air is injected into the venturi tube, a negative pressure is formed at the inlet end of the venturi tube, and the negative pressure chamber is connected to the fluidized powder bucket. The powder is adsorbed and reaches the inlet of the venturi tube and then is blown out of the venturi tube at high speed.

[0004] Although the venturi pump has a simple structure and low cost, there are many disadvantages in using the venturi pump for spraying: for example, the powder flow rate is fast, the powder tube is worn more severely, the consumption of compressed air is large, the powder pump core is extremely easy to wear, and it needs to be replaced every half month or even every week.

[0005] Therefore, now mostly a dense-phase pump is used as the powder conveying device and supplied to the spraying apparatus. And the previous dense-phase pumps, whether single-channel, forward two-channel, or reverse two-channel, each pump supplies one spraying device. Due to the complex control logic of the dense-phase pump, many electronic components such as PLC, solenoid valves, and electro-hydraulic proportional valves and many mechanical processing parts are required to cooperate, so its cost is greatly increased.

[0006] With the development of technology, powder coating has gradually entered the stage of refinement, automation, and large-scale production. In particular, the requirements for the first-pass powdering rate and the stability of coating quality are getting higher and higher, while the previous dilute-phase conveying system is increasingly difficult to meet the requirements, and the cost of the dense-phase pump conveying system is too high, and the technical requirements for maintenance and use are relatively high.

[0007] First, the venturi pump commonly used in powder coating at present can meet the needs of extensive production, but its powder supply accuracy is low and the replacement cycle of vulnerable parts is short, making it unable to be used in refined production; Second, for the dense-phase conveying system, due to its complex control logic and more components, its cost is too high, and the overall system is too large and occupies more space. Summary of the Invention

[0008] In view of the above problems, the purpose of the present application is to provide a comprehensive control system for high-precision quantitative powder conveying, which uses a reverse dual powder mixing system for powder mixing. The two channels work alternately to complete the powder suction - powder feeding process respectively, so as to realize the stable conveying of a large amount of powder.

[0009] To achieve the above purpose, the present invention provides a comprehensive control system for high-precision quantitative powder conveying, which includes an air pressure distribution control module, a pneumatic logic control module, a powder distribution valve module, and a filter element module; The filter element module is used to store powder, and includes a left filter element and a right filter element. The left filter element has a left filter element valve chamber and a left filter element air chamber, and the right filter element has a right filter element valve chamber and a right filter element air chamber; The powder distribution valve module is used to realize reverse dual-channel alternating powder mixing, and includes a left suction valve core, a right suction valve core, a left discharge valve core, a right discharge valve core, a total powder inlet, a lower left powder outlet, and a lower right powder outlet. The feeding end of the left suction valve core is connected to the total powder inlet through a lower left powder suction path, and the discharging end of the left suction valve core is connected to the left filter element valve chamber of the left filter element through an upper left powder suction path. The feeding end of the right suction valve core is connected to the total powder inlet through a lower right powder suction path, and the discharging end of the right suction valve core is connected to the right filter element valve chamber of the right filter element through an upper right powder suction path. The feeding end of the left discharge valve core is connected to the left filter element valve chamber of the left filter element through an upper left powder discharge path, and the discharging end of the left discharge valve core is connected to the lower left powder outlet. The feeding end of the right discharge valve core is connected to the right filter element valve chamber of the right filter element through an upper right powder discharge path, and the discharging end of the right discharge valve core is connected to the lower right powder outlet; The pneumatic logic control module is used to cooperate with the upper computer to realize the logic control of the powder distribution valve module, and includes a left suction valve core pneumatic control valve, a right suction valve core pneumatic control valve, a left discharge valve core pneumatic control valve, a right discharge valve core pneumatic control valve, a left powder feeding pneumatic control valve, a right powder feeding pneumatic control valve, a vacuum generator, a negative pressure switch valve, and a cleaning switch valve. The left suction valve core pneumatic control valve is connected to the left suction valve core, the right suction valve core pneumatic control valve is connected to the right suction valve core, the left discharge valve core pneumatic control valve is connected to the left discharge valve core, the right discharge valve core pneumatic control valve is connected to the right discharge valve core, the left powder feeding pneumatic control valve is connected to the left filter element air chamber of the left filter element, the right powder feeding pneumatic control valve is connected to the right filter element air chamber of the right filter element, the negative pressure switch valve is connected to the left powder feeding pneumatic control valve and the right powder feeding pneumatic control valve respectively through the vacuum generator, and the cleaning switch valve is connected to the left filter element valve chamber of the left filter element and the right filter element valve chamber of the right filter element respectively; The air pressure distribution control module is used to provide the required air supply pressure for the powder metering valve module, filter element module and pneumatic logic control module, and includes a total air inlet, a powder feeding air pressure regulating valve, a vacuum pressure regulating valve, a valve core air pressure regulating valve and a cleaning air pressure regulating valve. The total air inlet is respectively connected to the powder feeding air pressure regulating valve, the vacuum pressure regulating valve, the valve core air pressure regulating valve and the cleaning air pressure regulating valve. The powder feeding air pressure regulating valve is respectively connected to a left powder feeding air control valve and a right powder feeding air control valve. The vacuum pressure regulating valve is connected to a negative pressure switch valve. The valve core air pressure regulating valve is respectively connected to a left suction valve core air control valve, a right suction valve core air control valve, a left discharge valve core air control valve and a right discharge valve core air control valve. The cleaning air pressure regulating valve is connected to a cleaning switch valve.

[0010] To facilitate the cleaning within each module, the cleaning switch valve is connected to the left filter element valve chamber of the left filter element through a left cleaning air path, and a left one-way valve is provided on the left cleaning air path. The cleaning switch valve is connected to the right filter element valve chamber of the right filter element through a right cleaning air path, and a right one-way valve is provided on the right cleaning air path.

[0011] Through experiments, preferably, the valve core air pressure regulating valve adopts an electro-hydraulic proportional valve, and the pressure regulation range is 0.1 - 0.65 MPa. The vacuum pressure regulating valve is used to adjust the inlet pressure of the vacuum generator, and the pressure regulation range is 0.3 - 0.5 MPa. The powder feeding air pressure regulating valve is used to regulate the powder feeding air pressure. In the normal powder feeding state, the pressure regulation range is 0.1 - 0.35 MPa, and in the cleaning state, the pressure regulation range is 0.4 - 0.6 MPa. The cleaning air pressure regulating valve is used to regulate the cleaning air pressure, and the pressure regulation range is 0.4 - 0.5 MPa.

[0012] In summary, the present invention has the following beneficial effects: (1) The present invention adopts the dense phase conveying technology, which solves a series of problems such as large air consumption, high flow velocity, unstable flow rate, low flow rate, frequent replacement of vulnerable parts, and complex cleaning in the Venturi conveying. (2) Since the present invention adopts a reverse double-channel and double-outlet structure, each conveying pump can supply two spraying devices simultaneously without adding more controllers, solenoid valves and other electronic components, greatly reducing the costs, usage space and energy consumption of the dense phase pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is the system function partition diagram of the comprehensive control system for high-precision quantitative powder conveying of the present invention; Figure 2 is the system schematic diagram of the comprehensive control system for high-precision quantitative powder conveying of the present invention; Figure 3 is the schematic diagram of the left powder suction path of the present invention; Figure 4 is the schematic diagram of the left powder discharge path of the present invention; Figure 5 This is a schematic diagram of the first-stage cleaning passage of the present invention. Detailed implementation manner

[0014] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0015] As Figure 1 shown in the comprehensive control system for high-precision quantitative powder conveying, this set of control systems is divided into four zones according to different functions.

[0016] Zone A is the air pressure distribution zone of the system. This zone mainly supplies the required air supply pressure to each intake pipeline. To cooperate with necessary process actions, the air pressure distribution in Zone A can select a proportional valve (as shown in the figure), or a pressure regulating valve and a three-way valve can be used in parallel to form a multi-stage pressure air supply, and different pressure passages can be selected according to process requirements. Zone B is the main pneumatic logic area, which mainly cooperates with the host computer program to implement the necessary control logic of the dense phase system, including powder suction, powder delivery, cleaning, etc. Zone C is the powder metering valve system of the dense phase system. There are four pinch valves in this zone, which are opened or closed according to logic to realize the control of powder inlet and outlet. Zone D is the filter element zone, which consists of two filter elements. The inner cavity of the filter element is the powder storage area, and the inhaled powder is stored in this space for a short time. The outer cavity of the filter element is connected to Zone B, and negative pressure and positive pressure air are alternately supplied. The negative pressure air is used to suck powder from the inlet, and the positive pressure is used to distribute the powder at a certain speed. One end of the inner cavity of the filter element is connected to the valve in Zone C, and the other end is connected to the purge air in Zone B. There is a one-way valve at the connection end with the purge air. When cleaning is required, the entire powder pipeline can be quickly purged from the inner cavity. In addition, by controlling the opening and closing of the valve core in Zone C, the segmented purge function of the powder inlet pipeline and the powder outlet pipeline of the system can be realized.

[0017] Specifically, in combination with Figure 2 shown, the filter element module in Zone D includes a left filter element 102 and a right filter element 103. The left filter element 102 has a left filter element valve chamber 301 and a left filter element air chamber 203 inside, and the right filter element 103 has a right filter element valve chamber 302 and a right filter element air chamber 204 inside.

[0018] Specifically, in combination with Figure 2As shown in the figure, the powder metering valve module in area C includes a left suction valve core 105, a right suction valve core 106, a left discharge valve core 107, a right discharge valve core 108, a total powder inlet 311, a lower left powder outlet 309, and a lower right powder outlet 310. The feed end of the left suction valve core 105 is connected to the total powder inlet 311 through a lower left powder suction path 307, and the discharge end of the left suction valve core 105 is connected to the left filter element valve chamber 301 of the left filter element 102 through an upper left powder suction path 303. The feed end of the right suction valve core 106 is connected to the total powder inlet 311 through a lower right powder suction path 308, and the discharge end of the right suction valve core 106 is connected to the right filter element valve chamber 302 of the right filter element 103 through an upper right powder suction path 305. The feed end of the left discharge valve core 107 is connected to the left filter element valve chamber 301 of the left filter element 102 through an upper left powder discharge path 304, and the discharge end of the left discharge valve core 107 is connected to the lower left powder outlet 309. The feed end of the right discharge valve core 108 is connected to the right filter element valve chamber 302 of the right filter element 103 through an upper right powder discharge path 306, and the discharge end of the right discharge valve core 108 is connected to the lower right powder outlet 310.

[0019] Specifically, in combination with Figure 2 As shown in the figure, the pneumatic logic control module in area B includes a left suction valve core pneumatic control valve 109, a right suction valve core pneumatic control valve 110, a left discharge valve core pneumatic control valve 111, a right discharge valve core pneumatic control valve 112, a left powder feeding pneumatic control valve 113, a right powder feeding pneumatic control valve 114, a vacuum generator 115, a negative pressure switch valve 116, and a cleaning switch valve 117. The left suction valve core pneumatic control valve 109 is connected to the left suction valve core 105 through a left suction valve core air path 207. The right suction valve core pneumatic control valve 110 is connected to the right suction valve core 106 through a right suction valve core air path 208. The left discharge valve core pneumatic control valve 111 is connected to the left discharge valve core 107 through a left discharge valve core air path 209. The right discharge valve core pneumatic control valve 112 is connected to the right discharge valve core 108 through a right discharge valve core air path 210. The left powder feeding pneumatic control valve 113 is connected to the left filter element air cavity 203 of the left filter element 102 through a left powder suction and feeding air path 205. The right powder feeding pneumatic control valve 114 is connected to the right filter element air cavity 204 of the right filter element 103 through a right powder suction and feeding air path 206. The negative pressure switch valve 116 is connected to the vacuum generator 115. The vacuum generator 115 is connected to a total powder suction air path 215. The total powder suction air path 215 is respectively connected to the left powder feeding pneumatic control valve 113 and the right powder feeding pneumatic control valve 114 through a left powder suction air path 211 and a right powder suction air path 212. The cleaning switch valve 117 is connected to a total cleaning air path 218. The total cleaning air path 218 is connected to the left filter element valve chamber 301 of the left filter element 102 through a left cleaning air path 201, and a left one-way valve 101 is provided on the left cleaning air path 201. The total cleaning air path 218 is connected to the right filter element valve chamber 302 of the right filter element 103 through a right cleaning air path 202, and a right one-way valve 104 is provided on the right cleaning air path 202.

[0020] Specifically, in combination with Figure 2As shown in the figure, the air pressure distribution control module in area A includes a main air inlet 219, a powder feeding air pressure regulating valve 118, a vacuum pressure regulating valve 119, a valve core air pressure regulating valve 120, and a cleaning air pressure regulating valve 121. The main air inlet 219 is respectively connected to the powder feeding air pressure regulating valve 118, the vacuum pressure regulating valve 119, the valve core air pressure regulating valve 120, and the cleaning air pressure regulating valve 121. The powder feeding air pressure regulating valve 118 is connected to the main powder feeding air path 216. The main powder feeding air path 216 is respectively connected to a left powder feeding air control valve 113 and a right powder feeding air control valve 114 through a left powder feeding air path 213 and a right powder feeding air path 214. The vacuum pressure regulating valve 119 is connected to a negative pressure switch valve 116. The valve core air pressure regulating valve 120 is respectively connected to a left suction valve core air control valve 109, a right suction valve core air control valve 110, a left outlet valve core air control valve 111, and a right outlet valve core air control valve 112 through a valve core main air path 217. The cleaning air pressure regulating valve 121 is connected to a cleaning switch valve 117.

[0021] The left filter element 102 and the right filter element 103 have two working states, one is the powder suction state and the other is the powder feeding state. In the powder suction state, negative pressure is introduced into the left powder suction and feeding air path 205 and the right powder suction and feeding air path 206. The negative pressure acts on the left filter element valve chamber 301 and the right filter element valve chamber 302 through the outer wall of the filter element respectively, and cooperates with the opening and closing of the corresponding valve cores to complete the powder suction action. In the powder feeding state, positive pressure is introduced into the left powder suction and feeding air path 205 and the right powder suction and feeding air path 206. The positive pressure air passes through the filter element wall and blows out the powder sucked into the valve chamber, thus completing a working cycle. It can be seen from this that the overall working state of the filter element is that powder suction and powder feeding alternate. In order to prevent the filter element from being blocked after long-term operation, the absolute pressure of powder suction passing through the filter element should be less than the absolute pressure of powder feeding. Since the maximum negative pressure that a vacuum generator can generate is generally 0.07 MPa, the pressure of the powder feeding air is generally greater than 0.1 MPa.

[0022] The switching of the four spool valves of the present invention is controlled by corresponding 4 two-way three-way valves. The left suction spool air control valve 109 controls the opening and closing of the left suction spool 105, the right suction spool air control valve 110 controls the opening and closing of the right suction spool 106, the left outlet spool air control valve 111 controls the opening and closing of the left outlet spool 107, and the right outlet spool air control valve 112 controls the opening and closing of the right outlet spool 108. The whole system has two relatively independent working states. One is the normal powder supply state. At this time, after the spool valve is closed, it mainly bears negative pressure and low powder feeding pressure. In order to increase the service life, the clamping pressure of the spool valve is relatively low. The other is the cleaning (blowing) state. At this time, high-pressure air is introduced into the powder passage. In order to realize the segmented cleaning of the inlet and outlet of the system, the corresponding spool valve needs to be closed as required. At this time, it needs to bear high-pressure air, so the required clamping pressure should be slightly greater than the pressure of the cleaning compressed air. Otherwise, the spool valve leaks air and the segmented cleaning cannot be perfectly realized. Compressed air enters the inlet of the spool air pressure regulating valve 120 from the total air inlet 219. The spool air pressure regulating valve 120 selects an electro-pneumatic proportional valve, which adjusts the output clamping pressure to the spool total air path 217 according to the working state of the system. According to the preference, generally in the normal powder supply state of the system, the required clamping pressure of the spool air pressure regulating valve 120 is 0.1 - 0.4 MPa; in the cleaning (blowing) state, the required clamping pressure is 0.35 - 0.65 MPa. The four spool valves are made of rubber-like materials. The clamping force of the spool valve is provided by air pressure, and the opening force of the spool valve is provided by its own resilience. Therefore, the air control passages of the spool valves, such as the left suction spool air path 207, the right suction spool air path 208, the left outlet spool air path 209, the right outlet spool air path 210, etc., also need to have two states. One is the inflation and pressurization state, and the other is the evacuation state. The two inlets of the air control valves controlling each spool valve need to be connected to the clamping positive pressure and the atmosphere respectively.

[0023] The vacuum pressure regulating valve 119 adjusts the inlet pressure of the vacuum generator 115, and the general pressure regulation range is 0.3 - 0.5 MPa. By adjusting the opening time of the negative pressure switch valve 116, the powder suction amount of a single channel is adjusted. Increasing the proportion of the powder suction time, the powder suction amount will increase, and vice versa.

[0024] The powder feeding air pressure regulating valve 118 is used to adjust the powder feeding air pressure. According to different working states, the powder feeding air pressure also needs to be adjusted. In the normal powder feeding state, the powder feeding air pressure only needs to meet the powder transportation. According to the powder output amount, the diameter and length of the powder outlet pipe, the preferred range is between 0.1 - 0.35 MPa. In the cleaning (blowing) state, since high-pressure air is directly blown into the inner cavity of the filter element, in order to prevent the filter element from leaking powder, high-pressure powder feeding air is provided outside the filter element so that the air pressure outside the filter element is greater than the internal air pressure, generally between 0.4 - 0.6 Mpa.

[0025] The cleaning air pressure regulating valve 121 is used to regulate the cleaning air pressure. Since the pressure on the outer wall of the filter element should be slightly higher than that on the inner wall, the pressure of the cleaning air should be set lower than the powder feeding air pressure on the outer wall of the filter element to prevent the filter element from being contaminated. Generally, the preferred pressure is between 0.4 - 0.5 MPa.

[0026] As Figure 3 shown, during the powder suction stage of the left - hand system, the right suction spool pneumatic control valve 110 and the left outlet spool pneumatic control valve 111 are turned on, causing the right suction spool 106 and the left outlet spool 107 to close. The negative - pressure switch valve 116 is turned on, generating a negative pressure through the vacuum generator 115. The negative pressure passes through the total powder suction air path 215 and enters the left powder suction air path 211. The left powder feeding pneumatic control valve 113 switches to the negative - pressure path, causing the left suction and powder feeding air path 205 and the left filter element inner cavity 301 to be in a negative - pressure state. The powder is sucked in from the powder inlet 311, passes through the lower - left powder suction path 307, inside the left suction spool 105, and the upper - left powder suction path 303 in sequence, and enters the inside of the left filter element 102, completing the powder suction stage on the left side. The powder suction on the right side is the same as that on the left side.

[0027] As Figure 4 shown, during the powder discharging stage of the left - hand system, the left suction spool pneumatic control valve 109 and the right outlet spool pneumatic control valve 112 are turned on, causing the left suction spool 105 and the right outlet spool 108 to close. Compressed air passes through the powder feeding pressure regulating valve 118, enters the total powder feeding air path 216 and the left powder feeding air path 213. The left powder feeding pneumatic control valve 113 switches to the powder feeding path, and the powder feeding air enters the left suction and powder feeding air path 205, sending out the powder remaining in the inner cavity of the left filter element 102. Along the upper - left powder discharging path 304, it enters the inside of the left outlet spool 107 and finally enters the powder discharging pipe through the lower - left powder discharging path 309 and reaches the spraying appliance, completing the powder discharging on the left side. The powder discharging on the right side is the same as that on the left side.

[0028] During the automatic cleaning (blowing) stage, it is divided into 3 - stage cyclic cleaning: powder suction path cleaning, left powder discharging path cleaning, and right powder discharging path cleaning. As Figure 5The following shows the cleaning in the first stage. When entering the cleaning stage, first, the powder feeding air pressure regulating valve 118 switches to the cleaning state, with the pressure between (0.4 Mpa - 0.6 Mpa). Compressed air passes through the main powder feeding air path 216 to the left powder feeding air path 213. The left powder feeding air control valve 113 switches to the powder feeding path, and air enters the left suction powder feeding air path 205. The valve core air pressure regulating valve 120 switches to the cleaning state with the pressure between (0.4 Mpa - 0.6 Mpa). Compressed air enters the valve core main air path 217. The left outlet valve core air control valve 111 and the right outlet valve core air control valve 112 open, causing the left outlet valve core 107 and the right outlet valve core 108 to close. The inside of the filter element and the pipeline are cleaned. Then the cleaning switch valve 117 opens, enters the cleaning main air path 218, and respectively enters the left cleaning air path 201 and the right cleaning air path 202. The left one-way valve 101 and the right one-way valve 104 are opened to clean the filter element and the upper left powder suction path 303 of the pipeline, the left powder suction valve core 105, the lower left powder suction path 307, the upper right powder suction path 305, the right powder suction valve core 106, and the lower right powder suction path 308, which are then merged into the powder suction pipe for cleaning.

[0029] In the second stage, the left powder discharging pipeline is cleaned. The left powder suction valve core air control valve 109, the right powder suction valve core air control valve 110, and the right outlet valve core air control valve 112 are opened, causing the left powder suction valve core 105, the right powder suction valve core 106, and the right outlet valve core 108 to close, and the left powder discharging pipeline is cleaned. In the third stage, the right powder discharging pipeline is cleaned. The left powder suction valve core air control valve 109, the right powder suction valve core air control valve 110, and the left outlet valve core air control valve 111 are opened, causing the left powder suction valve core 105, the right powder suction valve core 106, and the left outlet valve core 107 to close, and the right powder discharging pipeline is cleaned.

[0030] It should be noted that in the description of the embodiments of the present invention, unless otherwise clearly specified and limited, terms such as "installation", "connection", "linkage", "setting", "providing", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0031] The above are all the preferred embodiments of this application. The protection scope of this application is not limited accordingly. Therefore, all equivalent changes made according to the structure, shape, principle, and application direction of this application should be covered within the protection scope of this application.

Claims

1. An integrated control system for accurately quantitatively conveying powder, characterized in that: It includes an air pressure distribution control module, a pneumatic logic control module, a powder metering valve module, and a filter element module; The filter element module is used to store powder and includes a left filter element (102) and a right filter element (103). The left filter element (102) has a left filter element valve chamber (301) and a left filter element air chamber (203) inside. The right filter element (103) has a right filter element valve chamber (302) and a right filter element air chamber (204) inside; The powder metering valve module is used to achieve reverse two-channel alternating powder metering and includes a left suction valve core (105), a right suction valve core (106), a left discharge valve core (107), a right discharge valve core (108), a total powder inlet (311), a lower left powder outlet (309), and a lower right powder outlet (310). The feeding end of the left suction valve core (105) is connected to the total powder inlet (311) through a lower left powder suction path (307), and the discharging end of the left suction valve core (105) is connected to the left filter element valve chamber (301) of the left filter element (102) through an upper left powder suction path (303). The feeding end of the right suction valve core (106) is connected to the total powder inlet (311) through a lower right powder suction path (308), and the discharging end of the right suction valve core (106) is connected to the right filter element valve chamber (302) of the right filter element (103) through an upper right powder suction path (305). The feeding end of the left discharge valve core (107) is connected to the left filter element valve chamber (301) of the left filter element (102) through an upper left powder discharge path (304), and the discharging end of the left discharge valve core (107) is connected to the lower left powder outlet (309). The feeding end of the right discharge valve core (108) is connected to the right filter element valve chamber (302) of the right filter element (103) through an upper right powder discharge path (306), and the discharging end of the right discharge valve core (108) is connected to the lower right powder outlet (310); The pneumatic logic control module is used to cooperate with the upper computer to achieve the logic control of the powder metering valve module and includes a left suction valve core pneumatic control valve (109), a right suction valve core pneumatic control valve (110), a left discharge valve core pneumatic control valve (111), a right discharge valve core pneumatic control valve (112), a left powder feeding pneumatic control valve (113), a right powder feeding pneumatic control valve (114), a vacuum generator (115), a negative pressure switch valve (116), and a cleaning switch valve (117). The left suction valve core pneumatic control valve (109) is connected to the left suction valve core (105), the right suction valve core pneumatic control valve (110) is connected to the right suction valve core (106), the left discharge valve core pneumatic control valve (111) is connected to the left discharge valve core (107), the right discharge valve core pneumatic control valve (112) is connected to the right discharge valve core (108), the left powder feeding pneumatic control valve (113) is connected to the left filter element air chamber (203) of the left filter element (102), the right powder feeding pneumatic control valve (114) is connected to the right filter element air chamber (204) of the right filter element (103), the negative pressure switch valve (116) is connected to the left powder feeding pneumatic control valve (113) and the right powder feeding pneumatic control valve (114) respectively through the vacuum generator (115), and the cleaning switch valve (117) is connected to the left filter element valve chamber (301) of the left filter element (102) and the right filter element valve chamber (302) of the right filter element (103) respectively; The air pressure distribution control module is used to provide the required air supply pressure for the powder metering valve module, filter element module and pneumatic logic control module, and includes a total air inlet (219), a powder feeding air pressure regulating valve (118), a vacuum pressure regulating valve (119), a valve core air pressure regulating valve (120) and a cleaning air pressure regulating valve (121). The total air inlet (219) is respectively connected to the powder feeding air pressure regulating valve (118), the vacuum pressure regulating valve (119), the valve core air pressure regulating valve (120) and the cleaning air pressure regulating valve (121). The powder feeding air pressure regulating valve (118) is respectively connected to a left powder feeding air control valve (113) and a right powder feeding air control valve (114). The vacuum pressure regulating valve (119) is connected to a negative pressure switch valve (116). The valve core air pressure regulating valve (120) is respectively connected to a left suction valve core air control valve (109), a right suction valve core air control valve (110), a left outlet valve core air control valve (111) and a right outlet valve core air control valve (112). The cleaning air pressure regulating valve (121) is connected to a cleaning switch valve (117).

2. The integrated control system for high-precision quantitative powder conveying according to claim 1, characterized in that: The cleaning switch valve (117) is connected to a left filter element valve chamber (301) of a left filter element (102) through a left cleaning air path (201), and a left one-way valve (101) is arranged on the left cleaning air path (201). The cleaning switch valve (117) is connected to a right filter element valve chamber (302) of a right filter element (103) through a right cleaning air path (202), and a right one-way valve (104) is arranged on the right cleaning air path (202).

3. The integrated control system for high-precision quantitative powder conveying according to claim 1, characterized in that: The valve core air pressure regulating valve (120) adopts an electro-hydraulic proportional valve, and the pressure regulation range is 0.1 - 0.65 MPa.

4. The comprehensive control system for high-precision quantitative powder conveying according to claim 1, wherein: The vacuum pressure regulating valve (119) is used to adjust the inlet pressure of a vacuum generator (115), and the pressure regulation range is 0.3 - 0.5 MPa.

5. The integrated control system for high-precision quantitative powder conveying according to claim 1, characterized in that: The powder feeding air pressure regulating valve (118) is used to regulate the powder feeding air pressure. In the normal powder feeding state, the pressure regulation range is 0.1 - 0.35 MPa, and in the cleaning state, the pressure regulation range is 0.4 - 0.6 Mpa.

6. The integrated control system for high-precision quantitative powder conveying according to claim 1, characterized in that: The cleaning air pressure regulating valve (121) is used to regulate the cleaning air pressure, and the pressure regulation range is 0.4 - 0.5 MPa.

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