A liquid filling machine

Abstract

This invention discloses a liquid filling machine, belonging to the field of liquid quantitative filling technology, to solve the evaporation problem during the filling of volatile liquids such as formaldehyde. It includes a filling nozzle and a container locking interface. The filling nozzle is height-adjustable and has a flexible sealing gasket around its perimeter. When lowering, it first seals the filling port of the container to be filled, and then opens the flexible valve body inside the filling port for filling, achieving double sealing to prevent liquid evaporation. A liquid pipeline connects to a liquid storage tank, and a gear metering pump and control system are installed to achieve quantitative filling. After filling, compressed air purges any residual liquid from the filling nozzle, and excess gas enters the liquid storage tank through an anti-evaporation air pipe to prevent evaporation. The liquid storage tank is equipped with a sealing plug and a pressure balancing valve to ensure pressure balance. Furthermore, the filling machine can be equipped with multiple independently controlled filling nozzles, driven by cylinders for height adjustment, improving efficiency and making it suitable for filling various containers of volatile liquids while ensuring operational safety.

Description

Technical Field

[0001] This invention relates to a liquid filling machine, belonging to the field of liquid quantitative filling technology. Background Technology

[0002] Formalin is a widely used and highly effective preservative in the medical field, playing a crucial role, especially in the long-term preservation of pathological specimens. Many existing medical specimen bags are pre-filled to a fixed size. To avoid using bags that are too large for the right size or running out of bags due to their small size, it is necessary to stock various sizes. This results in pre-filled specimen bags taking up a lot of space, and if damaged during transportation, formalin leakage can occur, impacting the environment. Therefore, the best method is to store formalin in sealed, large containers. When needed, appropriate bags are selected based on the size of the specimen for on-site filling. This method minimizes space usage, and using dedicated storage containers ensures the safest storage of formalin. Furthermore, selecting bags of appropriate sizes based on specimen size avoids the problem of mismatched pre-filled specimen bags. However, formalin is known for its strong, pungent odor. Therefore, in practice, effectively preventing formalin from evaporating and spreading into the work area during filling becomes a critical issue for ensuring the health and safety of operators. For operators, taking scientific and reasonable protective measures to ensure that formalin does not evaporate into the air is of great practical significance. This is not only related to their own occupational health, but also the key to ensuring the safety of the laboratory environment. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a liquid filling machine for filling formaldehyde, and to prevent formaldehyde from evaporating into the operating space during the filling process.

[0004] The specific technical solution of the present invention to solve the above-mentioned technical problems is as follows:

[0005] A liquid filling machine includes a filling nozzle and a container clamping interface. The container clamping interface is used to fix the container to be filled. The filling nozzle is connected to a liquid storage tank via a liquid pipeline, and the filling nozzle is movable. When the filling nozzle descends, it is inserted into the filling port of the container to be filled, which is clamped at the container clamping interface. The filling nozzle is provided with a flexible sealing gasket, which is used to seal the filling port of the container to be filled, preventing the liquid being filled from evaporating into the operating space.

[0006] Compared to existing technologies, this invention offers the following advantages: During the filling process, the flexible sealing gasket tightly seals the filling port of the container, effectively preventing volatile liquids from evaporating and escaping, thus maintaining fresh air in the operating space and ensuring the health and safety of operators. The container locking interface design ensures the stability of the container during the filling process, eliminating the need for manual support and reducing labor intensity. In summary, the liquid filling machine of this invention has significant advantages and practicality when filling volatile liquids.

[0007] Furthermore, the sealing gasket, made of elastic material, is positioned around the filling nozzle. As the filling nozzle descends, the sealing gasket first contacts the filling port of the container to be filled, forming a seal on the filling port. Subsequently, the filling nozzle continues to descend a certain distance to ensure the sealing effect of the flexible sealing gasket on the filling port. The advantage of this arrangement is that it can further improve the sealing performance. Since the flexible sealing gasket contacts and seals the filling port first, that is, before the filling nozzle begins to dispense liquid, the filling port is sealed, ensuring that the liquid being conveyed will not evaporate and escape into the operating space, thereby maintaining the cleanliness and safety of the operating space.

[0008] Furthermore, it also includes a compressed air pipeline. The filling nozzle is connected to the compressed air pipeline via a gas pipeline. The compressed air pipeline is equipped with a first electrically controlled valve. After the liquid filling is completed, the liquid pipeline is closed first, and then the compressed air pipeline is connected for a certain period of time to purge the filling nozzle with compressed air, cleaning the inside and end of the filling nozzle of any residual liquid. The advantage of this design is that it can effectively prevent the contamination problem caused by the evaporation of residual liquid on the filling nozzle.

[0009] Furthermore, a delivery pump is installed on the liquid pipeline. This delivery pump is electrically connected to a control system, which controls the pump to fill a set volume of liquid according to user instructions. The design of this delivery pump ensures stable and precise delivery of liquid to the filling nozzle, guaranteeing filling accuracy. The control system receives user instructions and controls the pump's operating time or the dosage it delivers, thereby fulfilling different liquid filling requirements.

[0010] Furthermore, the delivery pump is a gear metering pump. Gear metering pumps are known for their high precision and stability, providing accurate flow control during liquid filling. Their working principle involves the meshing of gears, which draws liquid in from the inlet and compresses it to the outlet during gear rotation, thus achieving quantitative liquid delivery. This pump design not only ensures filling accuracy but also significantly improves filling efficiency.

[0011] Furthermore, the liquid storage tank is equipped with a sealing plug, and the liquid pipeline is airtightly inserted within the sealing plug. The sealing plug is also equipped with a pressure balancing valve, which is a one-way valve with a flexible valve disc. This pressure balancing valve is designed to balance the air pressure inside and outside the liquid storage tank, ensuring that pressure differences during filling do not affect the stable delivery of the liquid. When liquid flows out of the liquid storage tank through the liquid pipeline, the air pressure inside the liquid storage tank gradually decreases. Without pressure balancing measures, this could lead to poor or interrupted liquid delivery. By installing the pressure balancing valve, when the air pressure inside the liquid storage tank decreases, outside air can smoothly enter the liquid storage tank through the flexible valve disc, thereby maintaining the pressure balance inside and outside the liquid storage tank. The one-way valve design further ensures that the liquid inside the liquid storage tank will not evaporate and escape into the operating space through the pressure balancing valve.

[0012] Furthermore, it also includes an anti-escape air tube. One end of the anti-escape air tube is arranged parallel to the filling nozzle and inserted into the container to be filled during filling. The other end of the anti-escape air tube is airtightly inserted into the sealing plug. After filling is completed, when the filling nozzle is purged with compressed air, excess compressed air enters the liquid storage tank through the anti-escape air tube. This effectively prevents the compressed air from carrying the filled liquid out of the operating space and contaminating it. The connection to the liquid storage tank is because the liquid storage tank itself is in a closed state. Even if the pressure is slightly higher than the outside pressure, the pressure balance valve is a one-way valve, so the liquid carried during purging will not escape into the operating space.

[0013] Furthermore, the filling port of the container to be filled is equipped with a flexible valve body. This flexible valve body can be opened by the descending filling nozzle and can automatically close based on its own elasticity after the filling nozzle rises. This design further enhances the sealing effect, ensuring that the liquid filled into the container will not escape or evaporate through the filling port. The use of the flexible valve body allows it to open during the filling process when the filling nozzle descends and contacts it. The filling nozzle then descends further through the flexible valve body, smoothly filling the container with liquid. Once the filling nozzle has completed its filling task and rises away, the flexible valve body, thanks to its excellent elasticity, quickly returns to the closed state, effectively preventing liquid escape and evaporation.

[0014] Furthermore, after the sealing gasket forms an effective seal at the filling port, the filling nozzle continues to descend before opening the flexible valve body inside the filling port. This creates a double seal between the flexible sealing gasket and the flexible valve body. After filling, the filling nozzle rises. Just as the filling nozzle leaves the flexible valve body and the valve body closes, the seal formed by the flexible sealing gasket remains effective. Subsequently, as the filling nozzle continues to rise, the sealing gasket detaches from the filling port, ensuring that throughout the entire process, the liquid in the container to be filled has no opportunity to directly communicate with the external operating space, preventing liquid from leaking into the operating space. In this process, the combined use of the flexible sealing gasket and the flexible valve body achieves double sealing protection.

[0015] Furthermore, the machine includes multiple independently controllable filling nozzles, each equipped with an independently controllable actuator, connecting pipeline, and control valve, which can be precisely adjusted according to preset parameters such as filling volume, speed, and pressure. This design allows the filling machine to simultaneously handle multiple different types of containers to be filled, meeting the filling needs of various products. In addition, the independently controllable filling nozzles effectively reduce waste during the filling process, improving filling accuracy and efficiency. During the filling process, the various filling nozzles work together to ensure smooth operation of the entire filling process. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the external structure of the liquid filling machine of the present invention;

[0017] Figure 2 This is a schematic diagram illustrating the working principle of Embodiment 1 of the liquid filling machine of the present invention;

[0018] Figure 3 This is a detailed schematic diagram of the filling nozzle of the liquid filling machine of the present invention;

[0019] Figure 4 This is a schematic diagram of the sealing plug for the liquid filling machine of the present invention;

[0020] Figure 5 This is a schematic diagram of the container card interface and the flexible valve body on the bag of the liquid filling machine of the present invention.

[0021] Figure 6 This is a schematic diagram illustrating the working principle of Embodiment 2 of the present invention;

[0022] The component names represented by each number in the attached diagram are as follows:

[0023] 1. Filling nozzle; 2. Container clamp interface; 3. Container to be filled; 4. Liquid storage tank; 5. Sealing gasket; 6. Compressed air pipeline; 7. First solenoid valve; 8. Gear metering pump; 9. Sealing plug; 10. Liquid pipeline; 11. Pressure balancing valve; 12. Anti-escape air pipe; 13. Air compressor; 14. Cylinder; 15. Second solenoid valve; 16. Pressure reducing valve; 17. Drive plate; 18. Spring; 19. Support plate; 20. Guide rod; 21. Silicone valve body. Detailed Implementation

[0024] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0025] Example 1:

[0026] A liquid filling machine, in this example, is used for storing formalin solution, and the filling machine is used for filling formalin solution with a pungent odor.

[0027] like Figure 1 As shown, the liquid filling machine includes three filling nozzles 1 and three corresponding container locking interfaces 2. The container locking interfaces 2 are used to fix the containers 3 to be filled. The filling nozzles 1 are connected to the liquid storage tank 4 (i.e., the formalin storage tank) via liquid pipes 10. The filling nozzles 1 can be raised and lowered. When the filling nozzles 1 are lowered, they are inserted into the filling opening of the containers 3 to be filled, which are locked at the container locking interfaces 2. Figure 3 As shown, the filling nozzle 1 is provided with a flexible sealing gasket 5. The sealing gasket 5 is spring-loaded around the filling nozzle 1 and is airtightly connected to the filling nozzle 1. When the filling nozzle 1 descends, the sealing gasket 5 first contacts the filling port of the container to be filled 3, forming a seal on the filling port, which is used to seal the filling port of the container to be filled 3 and prevent the liquid being filled from evaporating into the operating space.

[0028] In this specific example, such as Figure 3 As shown, the filling nozzle 1 is driven to rise and fall by a cylinder 14. A drive plate 17 is fixedly mounted on the output shaft of the cylinder 14. A guide rod 20 passes through the drive plate 17. The upper end of the guide rod 20 is provided with a limiting structure to prevent the guide rod 20 from falling off the drive plate 17. A rigid support plate 19 is fixedly mounted on the lower end of the guide rod 20. A spring 18 is provided between the support plate 19 and the drive plate 17. The spring 18 is sleeved on the guide rod 20. A flexible sealing gasket 5 is provided on the lower surface of the rigid support plate 19. The filling nozzle 1 is fixedly mounted on the drive plate 17 and passes through the rigid support plate 19 and the flexible sealing gasket 5 respectively.

[0029] like Figure 2As shown, the liquid filling machine also includes an air compressor 13, which includes a buffer tank. The filling nozzle 1 is connected to the buffer tank via a compressed air pipe 6. The compressed air pipe 6 has a first electrically controlled valve 7. After the formalin solution is filled, the control system controls the second electrically controlled valve 15 to close the liquid pipe 10 that delivers the formalin solution and connects the filling nozzle 1 to compressed air for 0.1 seconds to purge the filling nozzle 1 and blow the residual formalin at the end of the filling nozzle 1 into the bag body. This prevents the formalin adhering to the filling nozzle 1 from evaporating into the operating space and causing pollution to the operating environment after the sealed bag is removed.

[0030] The compressed air pipeline 6 can be connected to an external compressed air source or to a self-installed air compressor 13, with the pipeline 6 connected to the compressor's storage tank to meet the filling machine's compressed air requirements. Connecting to an external compressed air source offers greater flexibility, allowing access to different pressure levels based on the filling machine's needs, thus providing strong adaptability. A self-installed air compressor ensures a stable supply of compressed air, unrestricted by external sources. In practical applications, users can choose the appropriate compressed air supply method based on their needs and site conditions. Furthermore, to ensure the cleanliness and dryness of the compressed air, filters and dryers can be installed on the compressed air pipeline 6 to further improve filling quality and efficiency.

[0031] The liquid pipeline 10 is equipped with a gear metering pump 8, which is electrically connected to a control system. The control system controls the gear metering pump 8 to accurately fill a set volume of liquid according to user instructions.

[0032] like Figure 4 As shown, the liquid storage tank 4 is equipped with a sealing plug 9, and the liquid pipeline 10 passes through the sealing plug 9 in an airtight manner. The sealing plug 9 is also equipped with a pressure balancing valve 11. The pressure balancing valve 11 is a one-way valve with a flexible valve disc. When the pressure inside the liquid storage tank 4 is greater than the external pressure, the valve disc of the pressure balancing valve 11 closes to prevent the irritating gas inside the liquid storage tank 4 from escaping. When the external pressure is greater than the pressure inside the liquid storage tank 4, the pressure balancing valve 11 opens to allow external air to enter the liquid storage tank 4, forming a pressure balance between the inside and outside of the liquid storage tank 4, which facilitates the smooth pumping of formalin by the gear metering pump 8.

[0033] It also includes an anti-escaping air pipe 12, one end of which is arranged parallel to the filling nozzle 1 and inserted into the container 3 to be filled during filling. Figure 4As shown, the other end of the anti-escape air pipe 12 passes through the sealing plug 9 in an airtight manner. When the filling nozzle 1 is purged after the liquid filling is completed, the excess compressed air enters the liquid storage tank 4 through the anti-escape air pipe 12 to prevent compressed air carrying formaldehyde from escaping into the operating space.

[0034] The container 3 to be filled is a bag. Before being filled with liquid, the bag is in an air-vented state, meaning there is no air inside the bag. This prevents the liquid from squeezing out air during filling and causing the volatile liquid to escape. For volatile or easily oxidized liquids, the air-free state inside the bag can effectively reduce the contact between the liquid and air, thereby reducing the risk of liquid evaporation and oxidation.

[0035] like Figure 5 As shown, the filling port of the container to be filled 3 is provided with a flexible valve body. The flexible valve body can be a silicone valve body 21. The silicone valve body 21 can be opened by the descending filling nozzle 1. When the filling nozzle 1 descends, it can pass through the seam of the silicone valve body 21 to fill the formaldehyde. After the filling nozzle 1 rises, the silicone valve body 21 can automatically close based on its own elasticity to prevent the formaldehyde filled into the bag from evaporating and dissipating into the operating space when the filling nozzle 1 is detached and not yet sealed.

[0036] The sealing gasket 5 and the silicone valve body 21 together form two seals. After the flexible sealing gasket 5 forms an effective seal at the filling port, the filling nozzle 1 continues to descend, opening the flexible silicone valve body 21 inside the filling port of the container to be filled 3. After filling is completed, the filling nozzle 1 rises. After the filling nozzle 1 leaves the flexible silicone valve body 21, the silicone valve body 21 closes. As the filling nozzle 1 continues to rise, the sealing gasket 5 detaches from the filling port, ensuring that at any time, the formaldehyde inside the sealed bag cannot be directly connected to the outside, thus preventing formaldehyde from escaping into the operating space.

[0037] The filling nozzle is driven to rise and fall by a cylinder 14, which is connected to a compressed air pipeline 6. By precisely controlling the supply of compressed air, the cylinder 14 can smoothly and quickly drive the filling nozzle to rise and fall. Compressed air, as a power source, has the advantages of being clean and pollution-free, meeting the high requirements of modern production for environmental protection and hygiene.

[0038] Example 2:

[0039] like Figure 6 As shown, this example differs from Embodiment 1. Instead of using a gear metering pump 8 to deliver liquid, compressed air is depressurized by a pressure reducing valve 16 and then delivered to the liquid storage tank 4, creating a positive pressure inside the liquid storage tank 4. The amount of liquid delivered is controlled by controlling the opening time of the second solenoid valve 15. This structure further saves on the gear metering pump 8, resulting in lower hardware costs.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A liquid filling machine, comprising a filling nozzle (1) and a container locking interface (2), wherein the container locking interface (2) is used to fix a container (3) to be filled, the filling nozzle (1) is connected to a liquid storage tank (4) via a liquid pipeline (10), and the filling nozzle (1) is capable of rising and falling; when the filling nozzle (1) falls, the filling nozzle (1) is inserted into the filling port of the container (3) to be filled at the container locking interface (2), characterized in that, The filling nozzle (1) is provided with a flexible sealing gasket (5), which is used to seal the filling port of the container to be filled (3) to prevent the liquid being filled from evaporating into the operating space. The sealing gasket (5) is disposed around the filling nozzle (1). When the filling nozzle (1) descends, the sealing gasket (5) first contacts the filling port of the container to be filled (3) to form a seal on the filling port. The filling port of the container to be filled (3) is provided with a flexible valve body. The flexible valve body can be opened by the lowered filling nozzle (1) and can automatically close based on its own elasticity after the filling nozzle (1) rises. After the sealing gasket (5) forms an effective seal at the filling port, the filling nozzle (1) continues to descend, opening the flexible valve body inside the filling port. After filling is completed, the filling nozzle (1) rises. After the filling nozzle (1) leaves the flexible valve body, the flexible valve body closes. As the filling nozzle (1) continues to rise, the sealing gasket (5) disengages from the filling port.

2. The liquid filling machine according to claim 1, characterized in that, It also includes a compressed air pipeline (6), the filling nozzle (1) is connected to the compressed air pipeline (6) through a gas pipeline, and the compressed air pipeline (6) is provided with a first electrically controlled valve (7). After the liquid filling is completed, the liquid pipeline (10) is closed and the compressed air pipeline (6) is connected to purge the filling nozzle (1) to prevent liquid residue from remaining in the filling nozzle (1).

3. The liquid filling machine according to claim 1 or 2, characterized in that, The liquid pipeline (10) is equipped with a delivery pump, which is electrically connected to the control system. The control system fills a set volume of liquid according to user instructions.

4. The liquid filling machine according to claim 3, characterized in that, The delivery pump is a gear metering pump (8).

5. The liquid filling machine according to claim 4, characterized in that, The liquid storage tank (4) is provided with a sealing plug (9), and the liquid pipeline (10) is airtightly inserted inside the sealing plug (9). The sealing plug (9) is also provided with a pressure balancing valve (11), which is a one-way valve with a flexible valve disc.

6. The liquid filling machine according to claim 5, characterized in that, It also includes an anti-escape air tube (12), one end of which is arranged side by side with the filling nozzle (1) and inserted into the container to be filled (3) during filling. The other end of the anti-escape air tube (12) is airtightly inserted into the sealing plug (9). When the filling nozzle (1) is purged after filling, excess compressed air enters the liquid storage tank (4) through the anti-escape air tube (12).

7. The liquid filling machine according to any one of claims 1-3, characterized in that, It includes multiple independently controlled filling nozzles (1).

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