A closed constant-pressure control tank for filling

Abstract

The present invention discloses a closed constant-pressure control tank for filling, which is used for metering and filling liquid preparations, and comprises: a liquid storage tank, a bottom pressure sensor of the tank, a top liquid level sensor of the tank, a fourteenth switching valve, a second switching valve and an electro-pneumatic proportional valve. The bottom pressure sensor of the tank is used for detecting the internal pressure information of the liquid in the liquid storage tank; the top liquid level sensor of the tank is used for detecting the liquid level information of the liquid in the liquid storage tank; the fourteenth switching valve is arranged on the pipeline for the entry of steam, water and liquid medicine, and the fourteenth switching valve is used for controlling the entry amount of the liquid medicine according to the liquid level information; the second switching valve is arranged on the pipeline for the entry of clean compressed air; the electro-pneumatic proportional valve is arranged on the pipeline for the entry of clean compressed air, and the electro-pneumatic proportional valve is used for controlling the opening and closing of the second switching valve according to the internal pressure information of the liquid, so as to supplement air or relieve pressure to the cavity above the liquid surface in the liquid storage tank, thereby realizing constant-pressure filling. Compared with the prior art, the use of the present invention can achieve accurate filling metering, online cleaning and online sterilization, and is convenient to use.

Description

Technical Field

[0001] The present invention belongs to the technical field of filling equipment, and particularly relates to a closed constant-pressure control tank for filling. Background Art

[0002] The filling component is a key component on the filling machine in the production process of liquid preparations in the pharmaceutical industry. The filling method, accurate metering, and convenient use of cleaning and disinfection are the key technical issues that need to be focused on in the filling production of liquid preparations in the pharmaceutical industry.

[0003] The filling methods of existing large-capacity and small-capacity liquid filling machines generally adopt negative pressure type, gravity self-flow type, piston pump (glass pump / stainless steel metal pump / ceramic pump) type or peristaltic pump type filling. Specifically: For the existing negative pressure type filling method, vacuum negative pressure technology is adopted, and the liquid medicine is extracted for filling by forming a negative pressure circuit through bottle mouth sealing, and the filling volume is controlled by adjusting the filling liquid level height of the packaging container. For the existing gravity self-flow type filling method, the liquid storage tank operates in a non-closed manner, and the liquid level fluctuates greatly due to the impact of incoming liquid, and the self-weight pressure value of the liquid medicine in the tank also changes greatly, resulting in inaccurate control of the filling volume error. Finally, there will be a large amount of filling tail liquid, and the waste of liquid medicine is relatively serious, and the liquid storage tank and filling pipeline can only be cleaned and sterilized statically online. For the existing piston pump type filling method, the movement stroke of the piston rod in the piston pump is controlled by a mechanical transmission method to control the filling metering. The transmission structure is complex and the adjustment is not very convenient; cleaning and disinfection must be carried out after disassembling the pump body and pipeline, and online cleaning and sterilization cannot be realized, and it is convenient to use. For the existing peristaltic pump type filling method, the rotation number of the pump head rotor is controlled to control the filling metering. Its cleaning and disinfection must also be carried out after disassembling the pump head and pipeline, and online cleaning and sterilization cannot be realized, and it is convenient to use.

[0004] Therefore, due to the defects of the filling pipeline structure and metering method of the existing liquid filling device, the following deficiencies exist: the filling volume error is relatively large, and there is residual tail liquid, resulting in waste of liquid medicine; online cleaning cannot be realized or the online cleaning effect is not good, and it is inconvenient to use. Summary of the Invention

[0005] (1) Technical Problems to be Solved

[0006] Based on this, the present invention provides a closed constant-pressure control tank for filling to solve the technical problems of large filling volume error, waste of liquid medicine, and poor cleaning effect existing in the existing liquid filling device.

[0007] (2) Technical Solutions

[0008] To solve the above technical problems, the present invention proposes a closed constant-pressure control tank for filling, which is used for metering and filling liquid preparations, and includes: a liquid storage tank, a bottom pressure sensor of the tank, a top liquid level sensor of the tank, a fourteenth switching valve, a second switching valve, and an electro-pneumatic proportional valve. The bottom pressure sensor of the tank is arranged below the interior of the liquid storage tank and is used for detecting the internal pressure information of the liquid in the liquid storage tank; the top liquid level sensor of the tank is arranged above the interior of the liquid storage tank and is used for detecting the liquid level information of the liquid in the liquid storage tank; the fourteenth switching valve is arranged on the pipeline for the entry of steam, water, and liquid medicine connected to the liquid storage tank, and the fourteenth switching valve is used for controlling the amount of liquid medicine entering according to the liquid level information; the second switching valve is arranged on the pipeline for the entry of clean compressed air connected to the liquid storage tank; the electro-pneumatic proportional valve is also arranged on the pipeline for the entry of clean compressed air, and the electro-pneumatic proportional valve is used for controlling the opening and closing of the second switching valve according to the internal pressure information of the liquid, so as to supplement air or relieve pressure to the cavity above the liquid surface in the liquid storage tank, so as to achieve constant-pressure filling.

[0009] Preferably, a filling main pipe is arranged at the lower part of the liquid storage tank, the filling main pipe is connected to a plurality of filling heads, and a filling switching valve is arranged between each filling head and the liquid storage tank.

[0010] Preferably, the closed constant-pressure control tank for filling further includes a sterilization head and a cleaning pipeline. One sterilization head is correspondingly arranged for each filling head. One end of the sterilization head has a ferrule for clamping with the filling head, and the other end of the sterilization head is an outlet end communicated with the cleaning pipeline. A seventh switching valve is arranged on the cleaning pipeline; the top of the liquid storage tank is communicated with the pipeline for the entry of steam, water, and liquid medicine through a cleaning ball of the liquid storage tank and a third switching valve.

[0011] Preferably, the cleaning and sterilization unit further includes a sixth switching valve and a direct connection pipe connecting the liquid storage tank and the cleaning pipeline. A fifth switching valve is arranged on the direct connection pipe, and the outlet end of each sterilization head is communicated with the cleaning pipeline through the sixth switching valve.

[0012] Preferably, the closed constant-pressure control tank for filling further includes a foam recovery unit. The foam recovery unit includes a foam recovery tank, a foam absorption main pipe, and a tenth switching valve. The upper part of each filling head is communicated with the foam recovery tank through the foam absorption main pipe and the tenth switching valve. The foam recovery unit further includes a vacuum pumping assembly for evacuating the foam recovery tank and a fifteenth switching valve arranged at the bottom of the foam recovery tank. A vacuum pressure gauge is also arranged on the foam recovery tank.

[0013] Preferably, an air filter is arranged between the electro-pneumatic proportional valve and the second switching valve, and a first switching valve is arranged between the air filter and the electro-pneumatic proportional valve.

[0014] Preferably, the closed constant-pressure control tank for filling further includes a steam sterilization and condensate drainage pipeline, and the air filter is also communicated with the steam sterilization and condensate drainage pipeline through a twelfth switching valve, an eighth switching valve, and a steam trap in sequence.

[0015] Preferably, the bottom of the foam recovery tank is communicated with the steam sterilization and condensate drainage pipeline through a recovery tank condensate drain pipe, and a ninth switching valve is provided on the recovery tank condensate drain pipe; the recovery tank condensate drain pipe is also communicated with the cleaning pipeline; the top of the foam recovery tank is communicated with the steam, water, and liquid medicine inlet pipeline through a recovery tank cleaning ball and a fourth switching valve.

[0016] Preferably, the vacuum pumping assembly includes a water circulation vacuum pumping system connected to the foam recovery tank. An eleventh switching valve is provided between the foam recovery tank and the water circulation vacuum pumping system, and a vacuum regulating valve is provided between the eleventh switching valve and the water circulation vacuum pumping system. The water circulation vacuum pumping system includes a water pump cooling water discharge pipeline.

[0017] Preferably, the first switching valve, the second switching valve, the third switching valve, the fourth switching valve, the fifth switching valve, the sixth switching valve, the seventh switching valve, the eighth switching valve, the ninth switching valve, the tenth switching valve, the eleventh switching valve, and the twelfth switching valve are all pneumatic diaphragm valves. A thirteenth switching valve is provided on the steam, water, and liquid medicine inlet pipeline, and the thirteenth switching valve is a manual diaphragm valve; the fourteenth switching valve is a PID-controlled pneumatic diaphragm valve; ball valves are provided at the outlets of the cleaning pipeline and the steam sterilization and condensate drainage pipeline; temperature sensors are provided on the steam, water, and liquid medicine inlet pipeline, the filling main pipeline, the foam absorption main pipeline, and the steam sterilization and condensate drainage pipeline; a pressure sensor is also provided on the liquid storage tank.

[0018] (III) Beneficial effects

[0019] Compared with the prior art, the closed constant-pressure control tank for filling of the present invention has the following advantages:

[0020] When using the closed - type constant - pressure control tank for filling of the present invention to perform liquid filling, a liquid - surface air pressure can be formed above the liquid surface of the liquid storage tank. The liquid - surface air pressure reduces the impact fluctuation of liquid inlet at the liquid surface, ensures that the comprehensive pressure value of the liquid at the bottom of the tank remains constant, and can accurately control the filling volume. In addition, by using the closed - type constant - pressure control tank for filling of the present invention, the comprehensive pressure value of the liquid at the bottom of the tank can be kept constant. When the liquid surface drops in the final stage of filling, the electro - proportional valve at the upper part of the liquid surface controls the second switching valve to open for supplementing air to the cavity above the liquid surface in the liquid storage tank, so as to ensure that all the liquid medicine in the tank is filled completely without residual tail liquid, reducing the waste of liquid medicine. During use, only need to accurately adjust the liquid filling time of each filling head on the operation screen, then the accurate filling measurement of each filling head can be controlled. It can be used for both large - capacity and small - capacity liquid filling machines, with a wide range of applications, stable and reliable performance, and is convenient for control and adjustment. In addition, by using the present invention, on - line cleaning and on - line sterilization can also be realized, which is convenient to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0023] Explanation of the drawings:

[0024] 100. Input end of pure steam, purified water, and liquid medicine, 200. Input end of clean compressed air, 1. First switching valve, 2. Second switching valve, 3. Third switching valve, 4. Fourth switching valve, 5. Fifth switching valve, 6. Sixth switching valve, 7. Seventh switching valve, 8. Eighth switching valve, 9. Ninth switching valve, 10. Tenth switching valve, 11. Eleventh switching valve, 12. Twelfth switching valve, 13. Thirteenth switching valve, 14. Fourteenth switching valve, 15. Fifteenth switching valve, 16. Liquid storage tank, 17. Bottom pressure sensor of the tank, 18. Top liquid level sensor of the tank, 19. Electro-pneumatic proportional valve, 20. Pipe for steam, water, and liquid medicine to enter, 21. Pipe for clean compressed air to enter, 22. Filling main pipe, 23. Filling head, 24. Filling switching valve, 25. Sterilization head, 26. Cleaning pipeline, 27. Cleaning ball for the liquid storage tank, 28. Direct connection pipe, 29. Foam recovery tank, 30. Foam absorption main pipe, 31. Vacuum pressure gauge, 32. Air filter, 33. Steam trap, 34. Drain pipe for the recovery tank, 35. Cleaning ball for the recovery tank, 36. Water circulation vacuum pumping system, 37. Vacuum regulating valve, 38. Drain pipe for the cooling water of the water pump, 39. Ball valve, 40. Temperature sensor, 41. Pressure sensor, 42. Steam sterilization drain pipe, 43. Liquid inlet pipe. Detailed implementation manners

[0025] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following describes the detailed implementation manners of the present invention in conjunction with the accompanying drawings. Many specific details are set forth in the following description to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific implementations disclosed below.

[0026] The following combines the attached Figure 1 to further describe the closed constant-pressure control tank for filling of the present invention.

[0027] The present invention discloses a closed constant-pressure control tank for filling, which is used for the metering filling of liquid preparations, and includes: a liquid storage tank 16, a bottom pressure sensor 17 of the tank, a top liquid level sensor 18 of the tank, a fourteenth switching valve 14, a second switching valve 2, and an electro-pneumatic proportional valve 19. The bottom pressure sensor 17 of the tank is arranged below the interior of the liquid storage tank 16 and is used for detecting the internal pressure information of the liquid in the liquid storage tank 16; the top liquid level sensor 18 of the tank is arranged above the interior of the liquid storage tank 16 and is used for detecting the liquid level information of the liquid in the liquid storage tank 16; the fourteenth switching valve 14 is arranged on the steam, water, and liquid medicine inlet pipeline 20 connected to the liquid storage tank 16, and the fourteenth switching valve 14 is used for controlling the liquid medicine inlet amount according to the liquid level information; the second switching valve 2 is arranged on the clean compressed air inlet pipeline 21 connected to the liquid storage tank 16; the electro-pneumatic proportional valve 19 is also arranged on the clean compressed air inlet pipeline 21, and the electro-pneumatic proportional valve 19 is used for controlling the opening and closing of the second switching valve 2 according to the internal pressure information of the liquid, so as to supplement air or relieve pressure to the cavity above the liquid surface in the liquid storage tank 16, so as to achieve constant-pressure filling.

[0028] More specifically, the fourteenth switching valve 14 is a PID-controlled pneumatic diaphragm valve. It should be noted that the PID-controlled pneumatic diaphragm valve is a PID pneumatic regulating valve, specifically referring to a pneumatic diaphragm valve controlled by PID control, which uses an intelligent process controller to realize the functions of self-adjusting position and flow rate.

[0029] The closed constant-pressure control tank for filling in this embodiment is particularly suitable for the metering filling of liquid preparations in the pharmaceutical industry. Among them: the pure steam, purified water, and liquid medicine input end 100 is used for inputting pure steam or purified water or liquid medicine, and the clean compressed air input end is used for inputting clean compressed air.

[0030] During use, a filling head 23 is connected to the lower part of the liquid storage tank 16. During filling, a high-precision liquid level controller (the top liquid level sensor 18 of the tank), a pneumatic diaphragm proportional valve for liquid inlet (the fourteenth switching valve 14), a pneumatic proportional valve for clean compressed air inlet (the electro-pneumatic proportional valve 19 controlled by PID), and the bottom pressure sensor 17 of the tank for feedback of the pressure magnitude are jointly used to achieve precise control. A liquid surface air pressure is formed above the liquid surface of the liquid storage tank 16. The liquid surface air pressure reduces the impact fluctuation of liquid inlet on the liquid surface, ensuring that the comprehensive pressure value of the liquid at the bottom of the tank body (the sum of the self-weight pressure of the liquid in the tank and the clean compressed air pressure above the liquid in the tank) remains constant, so as to ensure that the pressure value of the liquid flowing in the filling pipeline connected to the filling head 23 is stable. Only by precisely adjusting the liquid filling time of each filling head 23 on the operation screen can the precise filling metering of each filling head 23 be controlled. Therefore, the closed constant-pressure control tank for filling in this embodiment can be applicable to liquid filling machines of various capacities, has a wide application range, stable and reliable performance, and can be conveniently controlled and adjusted.

[0031] In addition, the closed - type constant - pressure control tank for filling using the present invention can keep the comprehensive pressure value of the liquid at the bottom of the tank constant. When the liquid level drops in the final stage of filling, the electro - pneumatic proportional valve 19 at the upper part of the liquid surface controls the second switching valve 2 to open, so as to supplement air to the cavity above the liquid surface in the liquid storage tank 16, thereby ensuring that all the liquid medicine in the tank is filled completely without any remaining tail liquid, and reducing the waste of liquid medicine.

[0032] According to a specific embodiment of the present invention, a filling main pipe 22 is provided at the lower part of the liquid storage tank 16. The filling main pipe 22 is connected to a plurality of filling heads 23, and a filling switching valve 24 is provided between each filling head 23 and the liquid storage tank 16.

[0033] More specifically, the filling switching valve 24 is a pneumatic diaphragm valve.

[0034] More specifically, in this embodiment, 10 filling heads 23 are connected to the lower part of the liquid storage tank 16. In this embodiment, by providing a plurality of filling heads 23, the filling of multiple bottles of liquid preparations can be realized, and the filling efficiency can be greatly improved.

[0035] According to a specific embodiment of the present invention, the closed - type constant - pressure control tank for filling further includes a sterilizing head 25 and a cleaning pipeline 26. A sterilizing head 25 is correspondingly provided for each filling head 23. One end of the sterilizing head 25 has a ferrule for clamping with the filling head 23, and the other end of the sterilizing head 25 is an outlet end communicating with the cleaning pipeline 26. A seventh switching valve 7 is provided on the cleaning pipeline 26; the top of the liquid storage tank 16 is communicated with the steam, water, and liquid medicine inlet pipeline 20 through a liquid storage tank cleaning ball 27 and a third switching valve 3.

[0036] In this embodiment, the above - mentioned structure can be used to realize on - line cleaning and sterilization. During cleaning and sterilization, the operator manually sleeved the ferrule of each sterilizing head 25 onto the filling head 23 and clamped it tightly. The filling head 23 is communicated with the cleaning pipeline 26, and pure steam or purified water is introduced from the steam, water, and liquid medicine inlet pipeline 20. The pure steam or purified water passes through the liquid storage tank 16, the filling head 23, and the sterilizing head 25 in sequence and then is introduced into the cleaning pipeline 26, so as to realize on - line sterilization and cleaning. When filling is required, the sterilizing head 25 needs to be manually removed, and the filling mode program is entered to start filling.

[0037] According to a specific embodiment of the present invention, the cleaning and sterilization unit further includes a sixth switching valve 6 and a direct - connection pipe 28 connecting the liquid storage tank 16 and the cleaning pipeline 26. A fifth switching valve 5 is provided on the direct - connection pipe 28, and the outlet end of each sterilizing head 25 is communicated with the cleaning pipeline 26 through the sixth switching valve 6.

[0038] In this embodiment, by directly connecting the direct - connection pipe 28 to the cleaning pipeline 26, the liquid storage tank 16 can be separately cleaned and sterilized.

[0039] According to a specific embodiment of the present invention, the closed constant pressure control tank for filling also includes a foam recovery unit, which includes a foam recovery tank 29, a foam absorption main pipe 30 and a tenth switch valve 10. The upper part of each filling head 23 is connected to the foam recovery tank 29 via the foam absorption main pipe 30 and the tenth switch valve 10. The foam recovery unit also includes a vacuum assembly for evacuating the foam recovery tank 29 and a fifteenth switch valve 15 arranged at the bottom of the foam recovery tank 29. A vacuum pressure gauge 31 is also provided on the foam recovery tank 29.

[0040] In this embodiment, by setting a foam recovery unit, when filling liquid preparation products such as syrups and mixtures that are prone to generate foam during the filling process, the foam recovery tank 29 is evacuated using a vacuum assembly, and the foam in the filling head 23 enters the foam recovery tank 29 through the foam absorption main pipe 30, so that the foam during filling can be eliminated, ensuring the quality and efficiency of liquid medicine filling. The fifteenth switch valve 15 can be opened to discharge the liquid in the foam recovery tank 29. The vacuum pressure gauge 31 is used to display the pressure in the foam recovery tank 29.

[0041] According to a specific embodiment of the present invention, an air filter 32 is provided between the electrical proportional valve 19 and the second switch valve 2 , and a first switch valve 1 is provided between the air filter 32 and the electrical proportional valve 19 .

[0042] In this embodiment, by adding an air filter 32, the air entering the liquid storage tank 16 can be filtered to improve the cleanliness of the air and avoid air contamination of the liquid in the tank as much as possible.

[0043] According to a specific embodiment of the present invention, the air filter 32 is also connected to the steam sterilization drain pipe 42 via the twelfth switch valve 12, the eighth switch valve 8, and the drain valve 33 in sequence.

[0044] In this embodiment, when steam sterilization is performed on a part of the structure of the present invention, water vapor can be discharged through the steam sterilization drain pipe 42 to improve the sterilization effect.

[0045] According to a specific embodiment of the present invention, the bottom of the foam recovery tank 29 and the steam sterilization drain pipe 42 are connected through a recovery tank drain pipe 34, and a ninth switch valve 9 is provided on the recovery tank drain pipe 34; the recovery tank drain pipe 34 is also connected to the cleaning pipe 26; the top of the foam recovery tank 29 is connected to the steam, water, and liquid medicine inlet pipeline 20 through the recovery tank cleaning ball 35 and the fourth switch valve 4.

[0046] In this embodiment, through this structure, when the foam recovery tank 29 is cleaned and sterilized, the cleaning water and steam condensed water can be discharged in time, which is beneficial to further improve the cleaning and sterilization effects.

[0047] More specifically, the fifteenth switch valve 15 is a manual drain valve.

[0048] According to a specific embodiment of the present invention, the vacuum pumping assembly includes a water circulation vacuum pumping system 36 connected to the foam recovery tank 29. An eleventh switching valve 11 is provided between the foam recovery tank 29 and the water circulation vacuum pumping system 36. A vacuum regulating valve 37 is provided between the eleventh switching valve 11 and the water circulation vacuum pumping system 36. The water circulation vacuum pumping system 36 includes a water pump cooling water discharge pipe 38.

[0049] In this embodiment, the on-off between the foam recovery tank 29 and the water circulation vacuum pumping system 36 is controlled by the eleventh switching valve 11, and the vacuum regulating valve 37 is used to adjust the suction force of the vacuum system for pumping vacuum.

[0050] According to a specific embodiment of the present invention, the first switching valve 1, the second switching valve 2, the third switching valve 3, the fourth switching valve 4, the fifth switching valve 5, the sixth switching valve 6, the seventh switching valve 7, the eighth switching valve 8, the ninth switching valve 9, the tenth switching valve 10, the eleventh switching valve 11, and the twelfth switching valve 12 are all pneumatic diaphragm valves. A thirteenth switching valve 13 is provided on the pipeline 20 for the entry of steam, water, and liquid medicine, and the thirteenth switching valve 13 is a manual diaphragm valve; ball valves 39 are provided at the outlets of the cleaning pipeline 26 and the steam sterilization drain pipeline 42. Temperature sensors 40 are provided on the pipelines 20 for the entry of steam, water, and liquid medicine, the filling main pipeline 22, the foam absorption main pipeline 30, and the steam sterilization drain pipeline 42; a pressure sensor 41 is further provided on the liquid storage tank 16.

[0051] When using the closed constant-pressure control tank for filling of the present invention, after the media of liquid (water, steam), electricity, and gas are connected, through the combined action of preset parameters such as liquid level, pressure, and temperature and electrical and gas components, precise control is achieved. Only by setting parameters and performing simple operations on the operation screen, the metering filling, cleaning, and sterilization processes can be carried out, and it can be conveniently controlled and adjusted. According to the liquid level change signal output by the HT liquid level sensor (tank top liquid level sensor 18) at the top of the constant-pressure liquid storage tank 16, the liquid inflow amount of the PID-controlled pneumatic diaphragm valve (fourteenth switching valve 14) is controlled.

[0052] The signals of the bottom PT pressure sensor 17 and the top PT pressure sensor 41 of the tank are used to synchronously control the PID-controlled pneumatic diaphragm valve (fourteenth switching valve 14) and the electro-pneumatic proportional valve 19, so as to simultaneously supplement or relieve the pressure of the liquid medicine and the clean gas, thereby realizing constant-pressure filling control, and ensuring that all the liquid medicine in the liquid storage tank 16 is filled completely without residual tail liquid, reducing the waste of liquid medicine.

[0053] More specifically, in the present invention, the liquid storage tank 16, all the connecting parts and connecting pipelines adopt a closed quick-connect structure, which is convenient and fast to disassemble and replace. The liquid circulation pipeline operates smoothly without cleaning dead corners, which is beneficial to improving the effect of on-line cleaning and on-line disinfection and sterilization of the tank body and the filling pipeline. Moreover, with the closed quick-connect structure, there is no mechanical friction movement at the joint, and no friction particle pollution will be generated, ensuring the aseptic protection before liquid medicine filling.

[0054] The filling and cleaning processes of the present invention will be further described below.

[0055] 1. Pipeline state during filling

[0056] (1) The liquid medicine is metered and filled through the thirteenth switching valve 13, the fourteenth switching valve 14, and the filling switching valves 24 (a total of 10). The fourteenth switching valve 14 (according to the liquid level change signal output by the liquid level sensor 18 on the tank top) controls the size of the liquid inlet volume, and the 10 filling switching valves 24 can achieve bottleless filling stop for the corresponding filling heads 23.

[0057] (2) The replenishment of clean compressed air is realized through the electro-pneumatic proportional valve 19 (which controls the air supply or pressure relief of the cavity above the liquid level in the tank according to the pressure change signal output by the PT pressure sensor 41 at the top of the constant-pressure liquid medicine tank), the first switching valve 1, and the second switching valve 2 to achieve constant-pressure filling control.

[0058] (3) The foam generated during liquid medicine filling is extracted into the foam recovery tank 29 through the tenth switching valve 10 and the eleventh switching valve 11 by the vacuum system.

[0059] Description of constant-pressure filling control: The fourteenth switching valve 14 and the electro-pneumatic proportional valve 19 are synchronously controlled by the signals of the PT pressure sensor 17 at the tank bottom and the PT pressure sensor 41 at the tank top to achieve the simultaneous replenishment or pressure relief of the liquid medicine and the clean gas pressure.

[0060] 2. Pipeline state during sterilization: The first switching valve 1, the seventh switching valve 7, the eleventh switching valve 11, and the fifteenth switching valve 15 are closed, and the rest of the valves are open.

[0061] 3. Pipeline state during cleaning

[0062] (1) Cleaning of the liquid storage tank 16: The thirteenth switching valve 13, the fifth switching valve 5, and the seventh switching valve 7 are opened, and the ball valve 39 at the end of the cleaning pipeline 26 is opened.

[0063] (2) Cleaning of the filling pipeline: The thirteenth switching valve 13, the third switching valve 3, the 10 filling switching valves 24, the sixth switching valve 6, and the seventh switching valve 7 are opened, and the ball valve 39 at the end of the cleaning pipeline 26 is opened.

[0064] (3)Foam recycling pipeline cleaning: The thirteenth switching valve 13, the third switching valve 3, the tenth switching valve 10, the ninth switching valve 9, and the seventh switching valve 7 are opened, and the ball valve 39 at the end of the cleaning pipeline 26 is opened.

[0065] (4)Foam tank cleaning: The thirteenth switching valve 13, the fourth switching valve 4, the ninth switching valve 9, and the seventh switching valve 7 are opened, and the ball valve 39 at the end of the cleaning pipeline 26 is opened.

[0066] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "connected" and "connection" 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. It can be the communication inside two components or a "transmission connection", that is, power connection is carried out through various suitable methods such as belt drive, gear drive or sprocket drive. 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.

Claims

1. A closed constant pressure control tank for filling, used for the metering filling of liquid preparations, characterized in that, Including: A liquid storage tank (16), a bottom pressure sensor (17) of the tank, a top liquid level sensor (18) of the tank, a fourteenth switching valve (14), a second switching valve (2), and an electro-pneumatic proportional valve (19). The bottom pressure sensor (17) of the tank is arranged below the interior of the liquid storage tank (16) and is used to detect the internal pressure information of the liquid in the liquid storage tank (16); the top liquid level sensor (18) of the tank is arranged above the interior of the liquid storage tank (16) and is used to detect the liquid level information of the liquid in the liquid storage tank (16); the fourteenth switching valve (14) is arranged on the steam, water, and liquid medicine inlet pipeline (20) connected to the liquid storage tank (16), and the fourteenth switching valve (14) is used to control the liquid medicine inlet amount according to the liquid level information; the second switching valve (2) is arranged on the clean compressed air inlet pipeline (21) connected to the liquid storage tank (16); the electro-pneumatic proportional valve (19) is also arranged on the clean compressed air inlet pipeline (21), and the electro-pneumatic proportional valve (19) is used to control the opening and closing of the second switching valve (2) according to the internal pressure information of the liquid, so as to supplement air or relieve pressure to the cavity above the liquid level in the liquid storage tank (16) to achieve constant-pressure filling; A filling main pipe (22) is arranged at the lower part of the liquid storage tank (16), and the filling main pipe (22) is connected to a plurality of filling heads (23). A filling switching valve (24) is arranged between each filling head (23) and the liquid storage tank (16); The closed constant-pressure control tank for filling further includes a sterilizing head (25) and a cleaning pipeline (26). A sterilizing head (25) is correspondingly arranged for each filling head (23). One end of the sterilizing head (25) has a ferrule for clamping with the filling head (23), and the other end of the sterilizing head (25) is an outlet end communicated with the cleaning pipeline (26). A seventh switching valve (7) is arranged on the cleaning pipeline (26); the top of the liquid storage tank (16) is communicated with the steam, water, and liquid medicine inlet pipeline (20) through a liquid storage tank cleaning ball (27) and a third switching valve (3); The closed constant-pressure control tank for filling further includes a foam recovery unit. The foam recovery unit includes a foam recovery tank (29), a foam absorption main pipe (30), and a tenth switching valve (10). The upper part of each filling head (23) is communicated with the foam recovery tank (29) through the foam absorption main pipe (30) and the tenth switching valve (10). The foam recovery unit further includes a vacuum pumping assembly for evacuating the foam recovery tank (29) and a fifteenth switching valve (15) arranged at the bottom of the foam recovery tank (29). A vacuum pressure gauge (31) is also arranged on the foam recovery tank (29); An air filter (32) is provided between the electric proportional valve (19) and the second switching valve (2). The closed constant-pressure control tank for filling further includes a steam sterilization drain pipe (42). The air filter (32) is further communicated with the steam sterilization drain pipe (42) through a twelfth switching valve (12), an eighth switching valve (8), and a steam trap (33) in sequence. The bottom of the foam recovery tank (29) is communicated with the steam sterilization drain pipe (42) through a recovery tank drain pipe (34), and a ninth switching valve (9) is provided on the recovery tank drain pipe (34); the recovery tank drain pipe (34) is further communicated with the cleaning pipe (26); the top of the foam recovery tank (29) is communicated with the steam, water, and liquid medicine inlet pipe (20) through a recovery tank cleaning ball (35) and a fourth switching valve (4).

2. The closed constant pressure control tank for filling according to claim 1, characterized in that, A first switching valve (1) is provided between the air filter (32) and the electric proportional valve (19).

3. The closed constant-pressure control tank for filling according to claim 2, characterized in that, The vacuum pumping assembly includes a water circulation vacuum pumping system (36) connected to the foam recovery tank (29). A tenth switching valve (10) is provided between the foam recovery tank (29) and the water circulation vacuum pumping system (36), and a vacuum regulating valve (37) is provided between the tenth switching valve (10) and the water circulation vacuum pumping system (36). The water circulation vacuum pumping system (36) includes a water pump cooling water discharge pipe (38).

4. The closed constant-pressure control tank for filling according to claim 3, characterized in that, The first switching valve (1), the second switching valve (2), the third switching valve (3), the fourth switching valve (4), the seventh switching valve (7), the eighth switching valve (8), the ninth switching valve (9), the tenth switching valve (10), the eleventh switching valve (11), and the twelfth switching valve (12) are all pneumatic diaphragm valves. A thirteenth switching valve (13) is provided on the steam, water, and liquid medicine inlet pipe (20), and the thirteenth switching valve (13) is a manual diaphragm valve; the fourteenth switching valve (14) is a PID control pneumatic diaphragm valve; ball valves (39) are provided at the outlets of the cleaning pipe (26) and the steam sterilization drain pipe (42), and temperature sensors (40) are provided on the steam, water, and liquid medicine inlet pipe (20), the filling main pipe (22), the foam absorption main pipe (30), and the steam sterilization drain pipe (42); a pressure sensor (41) is further provided on the liquid storage tank (16).

Images