Quantitative monitoring feeding device for water-based paint stirring

By designing a water-based coating stirring quantitative monitoring feeding device including liquid and solid material silos, weighing with a measuring cylinder and weighing scale, and reducing the impact of adhesion materials through scraping rings, the problems of high cost and low feeding accuracy in the prior art are solved, and an efficient and accurate feeding process is achieved.

CN222872077UActive Publication Date: 2025-05-16SHANXI LANSHI FUQIANG THERMAL INSULATION MATERIAL MFG CO LTD
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Patent Information

Application Number
CN202421614334.3
Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-07-09
Publication Date
2025-05-16
Estimated Expiration
2034-07-09

AI Technical Summary

Technical Problem

The existing quantitative monitoring and feeding devices for water-based coatings are difficult to reduce production costs while ensuring efficiency, and liquid raw materials are prone to adhesion and affecting the feeding accuracy.

Method used

A water-based coating stirring quantitative monitoring feeding device including a liquid material silo and a solid material silo is designed, and the weighing of liquid and solid material is used to measure liquid and solid material with a fixed volume, and the impact of adhesion materials is reduced by scraping rings.

Benefits of technology

The production cost of the device is reduced, the feeding efficiency and accuracy are improved, and the production quality of water-based coatings is ensured.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model discloses a quantitative monitoring feeding device for water-based paint stirring, and relates to the technical field of water-based paint production, in particular to a device body, a liquid material bin and a solid material bin are arranged on the device body, vibrating rods are fixed in inner cavities of the liquid material bin and the solid material bin, and the vibrating rods are connected with the liquid material bin and the solid material bin. A discharging pipe is fixed to the middle of the bottom of an inner cavity of the liquid material bin, a first quantitative structure is arranged below the discharging pipe, and another discharging pipe is fixed to the middle of the bottom of an inner cavity of the solid material bin. According to the quantitative monitoring and feeding device for stirring the water-based paint, the quantitative cylinder with the fixed volume is adopted for weighing a liquid material, so that a weighing scale is omitted in the weighing process of the liquid material, and the production cost of the device is reduced; water-based paint production raw materials are placed in different stock bins, and a quantitative structure is arranged below each stock bin, so that when the device is used, different types of materials can be weighed at the same time, and the feeding efficiency is improved.
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Description

Technical Field

[0001] The utility model relates to the technical field of water-based paint production, in particular to a water-based paint stirring quantitative monitoring and feeding device. Background Art

[0002] Any coating that uses water as a solvent or dispersion medium can be called a water-based coating. Based on the type of binder in the coating, water-based coatings are divided into two categories: natural water-based coatings made from natural substances or minerals (such as potassium silicate) and petrochemical water-based coatings made from artificial synthetic resins (such as acrylic resin). During the production process of water-based coatings, it is necessary to add the raw materials in a quantitative manner into the mixing barrel. During this process, a quantitative monitoring and feeding device is required.

[0003] The working principle of the quantitative monitoring and feeding device disclosed in the prior art is generally as follows: a weighable quantitative feeding unit is arranged under the raw material box, the raw materials in the raw material box are slowly put into the quantitative feeding unit, the quantitative feeding unit weighs the raw materials added thereto in real time, and puts the raw materials whose weight meets the requirements into the stirring barrel. Since the raw materials for the production of water-based paints are divided into liquid raw materials and solid raw materials, and there are multiple types of liquid raw materials and solid raw materials, a quantitative feeding unit with a weighing function is arranged under each raw material box, which will increase the production cost of the device. Using a quantitative feeding unit with a weighing function to weigh multiple materials will reduce the feeding efficiency, and the liquid raw materials are easy to adhere to the inner wall of the feeding unit, affecting the feeding accuracy. Based on this, the present application proposes a water-based paint stirring quantitative monitoring and feeding device. Utility Model Content

[0004] The utility model provides a device for stirring and quantitatively monitoring and feeding a water-based paint, which solves the problems proposed in the above-mentioned background technology that the amount of feeding is controlled by real-time weighing, which makes it difficult to reduce the cost of the device while ensuring efficiency; and the liquid raw material is easy to adhere to the inner wall of the device, affecting the feeding accuracy.

[0005] The utility model provides the following technical solution: a water-based paint stirring quantitative monitoring feeding device, comprising a device body, a liquid material bin and a solid material bin are arranged on the device body, a vibrating rod is fixed in the inner cavity of both the liquid material bin and the solid material bin, a discharge pipe is fixed in the middle of the bottom of the inner cavity of the liquid material bin, a quantitative structure 1 is arranged below the discharge pipe, another discharge pipe is fixed in the middle of the bottom of the inner cavity of the solid material bin, a quantitative structure 2 is arranged below the other discharge pipe, and an electric ball valve is arranged at the bottom end of the discharge pipe;

[0006] The quantitative structure 1 includes a quantitative cylinder fixedly connected to the bottom of the device body and a hydraulic telescopic rod 1 fixedly connected to the bottom of the device body, a scraper ring 1 is fixedly connected to the bottom of the hydraulic telescopic rod 1, the scraper ring 1 contacts the inner wall of the quantitative cylinder, and a revolving door 1 is provided at the bottom of the quantitative cylinder; the quantitative structure 2 includes a fixed cylinder fixedly connected to the bottom of the device body, a hydraulic telescopic rod 2 fixedly connected to the top of the device body, a hydraulic telescopic rod 3 fixedly connected to the top of the device body and a limiting cylinder located in the inner cavity of the fixed cylinder, a revolving door 2 is provided at the bottom of the fixed cylinder, a weighing scale is fixed to the middle of the revolving door 2, a connecting ring is fixed to the bottom of the hydraulic telescopic rod 2, an electromagnet is fixed on the connecting ring, the electromagnet is magnetically attracted to the limiting cylinder when powered on, a scraper ring 2 is fixed to the bottom of the hydraulic telescopic rod 3, and the scraper ring 2 is adapted to the limiting cylinder.

[0007] Preferably, the bottom ends of the inner cavities of both the liquid material bin and the solid material bin are funnel-shaped.

[0008] Preferably, when the valve plate of the electric ball valve is in a horizontal state, the bottom of the valve plate of the electric ball valve and the bottom of the discharge pipe are at the same height.

[0009] Preferably, a rotating motor is fixedly connected to one side of the bottom end of the metering cylinder, and the end of the output shaft of the rotating motor is fixedly connected to a rotating door. The product of the volume value of the metering cylinder and the density value of the liquid material contained therein is the same as the mass of the liquid material required for the production of water-based paint.

[0010] Preferably, one side of the bottom end of the fixed cylinder is fixedly connected to a second rotating motor, and the end of the output shaft of the second rotating motor is fixedly connected to the second rotating door.

[0011] Preferably, the inner diameter of the connecting ring is the same as the inner diameter of the limiting cylinder, and an isolation gap is provided between the inner walls of the limiting cylinder and the fixed cylinder. When the second revolving door is closed, the limiting cylinder is located on the weighing scale, and the fixed cylinder is located outside the weighing scale.

[0012] Compared with the prior art, the utility model has the following beneficial effects:

[0013] 1. The water-based paint stirring quantitative monitoring and feeding device adopts a fixed-volume quantitative cylinder to weigh the liquid material, so that the use of a weighing scale is omitted in the process of weighing the liquid material, thereby reducing the production cost of the device; the water-based paint production raw materials are placed in different silos, and a quantitative structure is set under each silo, so that when the device is in use, different types of materials can be weighed at the same time, thereby improving the feeding efficiency.

[0014] 2. The water-based paint stirring quantitative monitoring and feeding device, through the setting of scraper ring 1 and scraper ring 2, scraper ring 1 can scrape off the liquid raw material adhering to the inner wall of the quantitative cylinder, and scraper ring 2 can scrape off the solid raw material adhering to the inner wall of the limiting cylinder, thereby reducing the feeding error of the device and ensuring the feeding accuracy of the device; through the setting of the weighing scale, the weighing scale can carry out real-time weighing and monitoring of the solid material dropped thereon, so that the device can accurately complete the addition of raw materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a front view of the structure of the utility model;

[0016] Figure 2 The utility model structure Figure 1 Bottom schematic diagram;

[0017] Figure 3 The utility model structure Figure 1 Schematic cross section;

[0018] Figure 4 It is a schematic diagram of the quantitative structure of the utility model;

[0019] Figure 5 It is a schematic diagram of the second quantitative structure of the utility model;

[0020] Figure 6 It is a schematic diagram of the second cross-section of the quantitative structure of the utility model.

[0021] In the figure: 1. device body; 2. liquid material bin; 3. solid material bin; 4. vibrating rod; 5. discharge pipe; 6. metering cylinder; 7. fixed cylinder; 8. electric ball valve; 9. revolving door 1; 10. rotating motor 1; 11. hydraulic telescopic rod 1; 12. scraper ring 1; 13. hydraulic telescopic rod 3; 14. connecting ring; 15. scraper ring 2; 16. hydraulic telescopic rod 2; 17. rotating motor 2; 18. revolving door 2; 19. limit cylinder; 20. weighing scale; 21. electromagnet. DETAILED DESCRIPTION

[0022] 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 in 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.

[0023] The utility model provides a water-based paint stirring quantitative monitoring and feeding device, comprising a device body 1, on which liquid material bins 2 and solid material bins 3 are arranged, and the number of liquid material bins 2 is the same as the number of types of liquid materials contained in the water-based paint production formula, and the number of solid material bins 3 is the same as the number of types of solid materials contained in the water-based paint production formula. The device can be used to store all materials contained in the production of water-based paint.

[0024] The bottom end of the inner cavity of the liquid material bin 2 is funnel-shaped, and a discharge pipe 5 is fixed in the middle of the bottom of the inner cavity of the liquid material bin 2. Through the setting of the discharge pipe 5, the liquid raw material in the liquid material bin 2 can be discharged. A vibrating rod 4 is fixedly connected to the inner cavity of the liquid material bin 2. When the vibrating rod 4 is working, the rotating shaft with eccentric mass installed at the center thereof transmits the centrifugal force generated by high-speed rotation to the vibrating rod housing through the bearing, so that the vibrating rod generates circumferential vibration. The vibration of the vibrating rod 4 causes the liquid material around it to vibrate, thereby preventing the liquid material from settling and stratifying, so that the density value of the liquid material in each part of the liquid material bin 2 is the same.

[0025] A quantitative structure 1 is provided below the discharge pipe 5, including a quantitative cylinder 6 fixedly connected to the bottom of the device body 1 and a hydraulic telescopic rod 11 fixedly connected to the bottom of the device body 1. A revolving door 9 is provided at the bottom of the quantitative cylinder 6, and the revolving door 9 is movably connected to the quantitative cylinder 6. A rotating motor 10 is fixedly connected to one side of the bottom end of the quantitative cylinder 6. The output shaft end of the rotating motor 10 is fixedly connected to the revolving door 9 through a reducer. Through the setting of the rotating motor 10, the rotation of the rotating motor 10 can drive the revolving door 9 fixedly connected thereto to rotate, and the revolving door 9 can contact or separate from the bottom of the quantitative cylinder 6. When the revolving door 9 is in contact with the bottom of the quantitative cylinder 6, the revolving door 9 is in contact with the bottom of the quantitative cylinder 6. When the bottom of the quantitative cylinder 6 is completely separated, the quantitative cylinder 6 is in an open state, and the liquid material in the quantitative cylinder 6 can be discharged under the action of gravity. When the revolving door 9 covers the bottom of the quantitative cylinder 6, the inner cavity of the quantitative cylinder 6 is in a sealed state, which is convenient for the liquid material to enter the quantitative cylinder 6. An electric ball valve 8 is provided at the bottom end of the discharge pipe 5, and when the valve plate of the electric ball valve 8 is in a horizontal state, the bottom of the valve plate of the electric ball valve 8 is at the same height as the bottom of the discharge pipe 5. Through the setting of the electric ball valve 8, the electric ball valve 8 can completely separate the quantitative cylinder 6 from the discharge pipe 5, thereby preventing the residual material in the discharge pipe 5 from affecting the weighing accuracy of the quantitative cylinder 6.

[0026] The product of the volume value of the metering cylinder 6 and the density value of the liquid material contained therein is the same as the mass of the liquid material required for the production of water-based paint. That is, when the device is in use, when the liquid material fills the inner cavity of the metering cylinder 6, the mass of the liquid material in the metering cylinder 6 is the same as the mass of the liquid material required for the production of water-based paint. The step of weighing the liquid material using a weighing scale is omitted, thereby reducing the production cost of the device and improving the weighing efficiency of the liquid material. The mass of the liquid material weighed by the metering cylinder 6 can be kept consistent, thereby ensuring the production quality of the water-based paint.

[0027] A scraper ring 12 is fixedly connected to the bottom of the hydraulic telescopic rod 11, and the scraper ring 12 contacts the inner wall of the metering cylinder 6. Through the setting of the hydraulic telescopic rod 11, the extension and retraction of the hydraulic telescopic rod 11 can change the position of the scraper ring 12 fixedly connected thereto, and the scraper ring 12 can scrape off the material adhering to the inner wall of the metering cylinder 6, thereby reducing the weighing error of the liquid material.

[0028] The outer surfaces of the scraper ring 12, the metering cylinder 6 and the rotating door 9 are all coated with an anti-stick coating, and the material of the anti-stick coating can be polytetrafluoroethylene. By setting the anti-stick coating, the probability of liquid material adhering to the quantitative structure 1 is reduced, which facilitates the cleaning of the quantitative structure 1.

[0029] The bottom end of the inner cavity of the solid material bin 3 is funnel-shaped, and another discharge pipe 5 is provided in the middle of the bottom of the inner cavity of the solid material bin 3. Another electric ball valve 8 is provided at the bottom of the other discharge pipe 5, and another vibrating rod 4 is fixed in the inner cavity of the solid material bin 3. The setting of the other vibrating rod 4 facilitates the falling of solid materials.

[0030] A quantitative structure 2 is provided below the other discharge pipe 5, and the quantitative structure 2 includes a fixed cylinder 7 fixedly connected to the bottom of the device body 1, a hydraulic telescopic rod 2 16 fixedly connected to the top of the device body 1, a hydraulic telescopic rod 3 13 fixedly connected to the top of the device body 1 and a limiting cylinder 19 located in the inner cavity of the fixed cylinder 7. A revolving door 2 18 is provided at the bottom of the fixed cylinder 7, and a rotating motor 2 17 is fixedly connected to one side of the bottom end of the fixed cylinder 7. The output shaft end of the rotating motor 2 17 is fixedly connected to the revolving door 2 18 through a reducer. Through the setting of the rotating motor 2 17, the rotation of the rotating motor 2 17 can drive the revolving door 2 18 connected thereto to rotate, and the revolving door 2 18 can close or open the bottom of the fixed cylinder 7.

[0031] A connecting ring 14 is fixed to the bottom of the hydraulic telescopic rod 16, and an electromagnet 21 is fixed to the connecting ring 14. The electromagnet 21 is magnetically attracted to the limiting cylinder 19 when it is powered on. The limiting cylinder 19 is made of ferromagnetic material, and the material of the limiting cylinder 19 can be metal iron. Through the setting of the electromagnet 21, when the electromagnet 21 is powered on, the electromagnet 21 is magnetically connected to the limiting cylinder 19, and the hydraulic telescopic rod 16 can limit the limiting cylinder 19, which is convenient for the quantitative structure 2 to open. When the electromagnet 21 is in the power-off state, under the action of the hydraulic telescopic rod 16, the connecting ring 14 and the limiting cylinder 19 can be separated, so as to avoid the connecting ring 14 affecting the limiting cylinder 19, so as to facilitate the limiting cylinder 19 to limit the material. There is an isolation gap between the limiting cylinder 19 and the inner wall of the fixed cylinder 7, which can avoid the fixed cylinder 7 from affecting the limiting cylinder 19.

[0032] A weighing scale 20 is fixed in the middle of the revolving door 18. The weighing scale 20 can weigh and monitor the solid materials dropped thereon, so as to accurately complete the addition of raw materials. When the revolving door 18 blocks the bottom of the fixed cylinder 7, the fixed cylinder 7 is located outside the weighing scale 20, the fixed cylinder 7 is in contact with the revolving door 18, the limiting cylinder 19 is located on the weighing scale 20, and when the connecting ring 14 is separated from the limiting cylinder 19, under the action of gravity, the limiting cylinder 19 can be placed on the weighing scale 20, and the limiting cylinder 19 can limit the object material, so that the weighing scale 20 can weigh the solid material.

[0033] A scraper ring 2 15 is fixed at the bottom of the hydraulic telescopic rod 3 13, and the scraper ring 2 15 is adapted to the limiting cylinder 19. The inner diameter of the connecting ring 14 is the same as the inner diameter of the limiting cylinder 19. Through the setting of the hydraulic telescopic rod 3 13, the extension and retraction of the hydraulic telescopic rod 3 13 can change the movement of the scraper ring 2 15 connected thereto, and the scraper ring 2 15 can scrape off the solid material adhering to the inner wall of the limiting cylinder 19 when it moves.

[0034] From the above description of quantitative structure 2, it can be seen that quantitative structure 2 uses a weighing scale to weigh solid materials, and when the solid materials are weighed, the limiting cylinder 19 limits the solid materials, and the limiting cylinder 19 will not contact other structures, which can improve the accuracy of solid material weighing.

[0035] The electrical components involved in this application are all prior art, and technicians in this field are familiar with their connection methods. Through these technicians, all the electrical components in this application are connected to their compatible power supplies through wires, and according to the actual situation, a suitable controller is selected to meet the needs of quantitative monitoring and adding during the production of water-based paint. Please refer to the description below for specific connections and control sequences. The electrical connections are completed in a sequential working order, and the detailed connection methods are well known in the art. The following mainly introduces the working principles and processes, and no further explanation of electrical control is given.

[0036] In summary: when the water-based paint stirring quantitative monitoring and feeding device is used, the device is fixed above the stirring barrel used for water-based paint production, the liquid material in the water-based paint production formula is placed in the liquid material bin 2, and the solid material in the water-based paint production formula is placed in the solid material bin 3. When the water-based paint is produced, when it is necessary to add the raw material into the stirring barrel, if the raw material is a liquid raw material, the electric ball valve 8 below the liquid material bin 2 where the raw material is located works, so that the discharge pipe 5 is in an open state, and the liquid raw material enters into the discharge pipe 5 under the action of gravity. In the dosing cylinder 6 below it, after the dosing cylinder 6 is filled, the electric ball valve 8 is closed. At this time, the mass of the material placed in the dosing cylinder 6 is the same as the mass of the raw materials used in the production of water-based paint. The rotating motor 10 drives the revolving door 9 to rotate. When the dosing cylinder 6 is opened, the quantitatively weighed liquid raw materials enter the stirring barrel used for the production of water-based paint under the action of gravity, realizing the quantitative feeding function. After the material is discharged, the hydraulic telescopic rod 11 drives the scraper ring 12 to work, and the material adhering to the inner wall of the dosing cylinder 6 is scraped off. The scraped material falls into the stirring barrel to reduce the feeding error.

[0037] If the added raw material is a solid raw material, the electric ball valve 8 below the solid material bin 3 where the solid raw material is located works, and the solid material falls into the limiting cylinder 19 under the action of gravity. The weighing scale 20 performs real-time weighing and monitoring of the solid material until the weight of the solid material meets the demand. When the solid material needs to be discharged, the hydraulic telescopic rod 2 16 drives the connecting ring 14 to move downward until the connecting ring 14 contacts the top of the limiting cylinder 19, and the electromagnet 21 is energized. The electromagnet 21 and the limiting cylinder 19 are magnetically attracted, and the position of the limiting cylinder 19 is fixed by the hydraulic telescopic rod 2 16. The rotating motor 2 17 drives the revolving door 2 18 to rotate. When the bottom of the limiting cylinder 19 is in an open state, the solid material falls into the mixing barrel for water-based paint production under the action of gravity, realizing the quantitative feeding function, and after the solid material is discharged, the hydraulic telescopic rod 3 13 drives the scraper ring 2 15 to move to prevent the solid material from adhering to the inner wall of the limiting cylinder 19 and reduce the feeding error.

[0038] During use of the device, the vibrating rod 4 is in a working state, so that the density of the liquid material at different heights remains consistent and the falling of the material is facilitated.

[0039] The standard parts used in the utility model can be purchased from the market, and the special-shaped parts can be customized according to the description in the specification and the drawings. The specific connection methods of each part adopt the conventional means such as mature bolts, rivets, welding, etc. in the prior art. The machinery, parts and equipment all adopt the conventional models in the prior art and will not be described in detail here. The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field. Although the embodiments of the utility model have been shown and described, it can be understood by ordinary technicians in this field that various changes, modifications, substitutions and modifications can be made to these embodiments without departing from the principle and spirit of the utility model. The scope of the utility model is defined by the attached claims and their equivalents.

Claims

1. A water-based paint stirring quantitative monitoring feeding device, comprising a device body (1), characterized in that: The device body (1) is provided with a liquid material bin (2) and a solid material bin (3), and a vibrating rod (4) is fixed in the inner cavity of both the liquid material bin (2) and the solid material bin (3). A discharge pipe (5) is fixed in the middle of the bottom of the inner cavity of the liquid material bin (2), and a quantitative structure 1 is provided below the discharge pipe (5). Another discharge pipe (5) is fixed in the middle of the bottom of the inner cavity of the solid material bin (3), and a quantitative structure 2 is provided below the other discharge pipe (5). An electric ball valve (8) is provided at the bottom end of the discharge pipe (5); The quantitative structure 1 comprises a quantitative cylinder (6) fixedly connected to the bottom of the device body (1) and a hydraulic telescopic rod (11) fixedly connected to the bottom of the device body (1), a scraper ring (12) fixedly connected to the bottom of the hydraulic telescopic rod (11), the scraper ring (12) contacts the inner wall of the quantitative cylinder (6), and a revolving door (9) is provided at the bottom of the quantitative cylinder (6); the quantitative structure 2 comprises a fixed cylinder (7) fixedly connected to the bottom of the device body (1), a hydraulic telescopic rod (16) fixedly connected to the top of the device body (1), and a revolving door (9) fixedly connected to the bottom of the device body (1). A hydraulic telescopic rod three (13) and a limiting cylinder (19) located in the inner cavity of the fixed cylinder (7); a revolving door two (18) is provided at the bottom of the fixed cylinder (7); a weighing scale (20) is fixed in the middle of the revolving door two (18); a connecting ring (14) is fixed at the bottom of the hydraulic telescopic rod two (16); an electromagnet (21) is fixed on the connecting ring (14); the electromagnet (21) is magnetically attracted to the limiting cylinder (19) when powered; a scraper ring two (15) is fixed at the bottom of the hydraulic telescopic rod three (13); the scraper ring two (15) is adapted to the limiting cylinder (19).

2. A water-based paint stirring quantitative monitoring and feeding device according to claim 1, characterized in that: The bottom ends of the inner cavities of both the liquid material bin (2) and the solid material bin (3) are funnel-shaped.

3. A water-based paint stirring quantitative monitoring and feeding device according to claim 1, characterized in that: When the valve plate of the electric ball valve (8) is in a horizontal state, the bottom of the valve plate of the electric ball valve (8) and the bottom of the discharge pipe (5) are at the same height.

4. A water-based paint stirring quantitative monitoring and feeding device according to claim 1, characterized in that: A rotating motor 1 (10) is fixedly connected to one side of the bottom end of the metering cylinder (6), and the end of the output shaft of the rotating motor 1 (10) is fixedly connected to a rotating door 1 (9). The product of the volume value of the metering cylinder (6) and the density value of the liquid material contained therein is the same as the mass of the liquid material required for the production of water-based paint.

5. The device for stirring and quantitatively monitoring and feeding water-based paint according to claim 1, characterized in that: One side of the bottom end of the fixed cylinder (7) is fixedly connected to a second rotating motor (17), and the output shaft end of the second rotating motor (17) is fixedly connected to a second rotating door (18).

6. The device for stirring and quantitatively monitoring and feeding water-based paint according to claim 1, characterized in that: The inner diameter of the connecting ring (14) is the same as the inner diameter of the limiting cylinder (19), and an isolation gap is provided between the inner walls of the limiting cylinder (19) and the fixed cylinder (7). When the second revolving door (18) is closed, the limiting cylinder (19) is located on the weighing scale (20), and the fixed cylinder (7) is located outside the weighing scale (20).