Diaphragm one-way valve type bacteria blocking filter for liquid dropping device and air permeability comparison test method

Abstract

The diaphragm one-way valve type bacteria-blocking filter comprises a bacteria-blocking filter membrane, a T-shaped rubber ring is arranged on the outer side of the bacteria-blocking filter membrane in an injection molding mode, an air hole penetrating through the T-shaped rubber ring is axially formed in the T-shaped rubber ring, the bacteria-blocking filter membrane is transversely arranged in the large-diameter end of the T-shaped rubber ring and blocks the air hole, and the air hole is communicated with the T-shaped rubber ring. An installation groove is formed in the T-shaped rubber ring in a downward extending mode, a one-way diaphragm is arranged in the installation groove and comprises a positioning ring, an elastic blocking piece and an elastic connecting wire, the positioning ring, the elastic blocking piece and the elastic connecting wire are integrally formed, the positioning ring is clamped in the installation groove, the elastic blocking piece is attached to the bottom wall of the T-shaped rubber ring in a zero-pressure mode and blocks an air hole, and the elastic connecting wire is connected with the T-shaped rubber ring. And the elastic connecting wires are circumferentially and uniformly distributed between the positioning ring and the elastic plugging sheet. The liquid dropping bottle has the advantages that the bacteria-blocking filter membrane is not in contact with liquid medicine in the liquid dropping bottle any more, so that membrane holes in the bacteria-blocking filter membrane cannot be blocked, the hydrophobicity of the bacteria-blocking filter membrane cannot be damaged, and complete hydrophobicity and air permeability are kept.

Description

Technical Field

[0001] The present invention relates to the field of medical packaging, and particularly to a diaphragm one-way valve type bacteria-blocking filter for a dropper and a method for comparing air permeability tests. Background Art

[0002] In daily life, precise drug administration is required using a dropper bottle, and the most common one is the eye drop bottle. Currently, the dropper bottles on the market have problems such as the backflow of the liquid medicine into the bottle after being contaminated by air and the remaining liquid medicine on the dropper head after dropping. To address these problems, there has emerged a sterile dropper bottle with an air-blocking type that can externally process the residual liquid, with the authorization number: CN118415813B. After dropping, under the action of negative pressure, the residual liquid medicine will enter the isolation groove of the valve body mixed with air. After the residual liquid medicine and air enter the isolation groove, they will be separated. The residual liquid medicine will flow in the isolation groove, and the air will flow back to the bottle body through the sterilization filter element in the air return hole to make the bottle body expand and recover. In this way, the residual liquid medicine will not block the sterilization filter element and affect the backflow effect. However, during actual use, it is found that after the liquid medicine comes into contact with the sterilization filter membrane, the liquid medicine will remain on the sterilization filter membrane, and the liquid medicine remaining on the membrane pores will precipitate crystals, thus blocking the membrane pores, resulting in an increase in the filtration resistance of the sterilization filter membrane, affecting the air backflow, and the bottle body cannot be restored in time. Moreover, the biological components (such as hyaluronic acid) in the liquid medicine will form a hydrophilic pollution layer on the surface of the sterilization filter membrane, covering the original reticular gap structure of the sterilization filter membrane, thereby destroying the air passing efficiency of the sterilization filter membrane. When dropping, the sterilization filter membrane cannot achieve good air permeability, and the bottle body cannot be restored, resulting in the failure of the function when used again. Summary of the Invention

[0003] The purpose of the present invention is to provide a diaphragm one-way valve type bacteria-blocking filter for a dropper that can prevent the liquid medicine from coming into contact with the bacteria-blocking filter membrane and does not hinder the air backflow, and a method for comparing air permeability tests thereof.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a diaphragm one-way valve type bacteria-blocking filter for a dropper, comprising: a hydrophobic bacteria-blocking filter membrane, a T-shaped rubber ring is injection-molded and compounded on the outer side of the bacteria-blocking filter membrane, an air hole penetrating the T-shaped rubber ring is axially arranged in the T-shaped rubber ring, the bacteria-blocking filter membrane is horizontally placed in the large-diameter end of the T-shaped rubber ring and blocks the air hole, an installation groove is extended downwardly on the T-shaped rubber ring, a one-way diaphragm is arranged in the installation groove, and the one-way diaphragm comprises: an integrally formed positioning ring, an elastic sealing piece and an elastic connecting wire, the positioning ring is clamped in the installation groove, and the one-way diaphragm comprises: an integrally formed positioning ring, an elastic sealing piece and an elastic connecting wire, and the positioning ring is clamped in the installation groove. The groove provides rigid support for the one-way diaphragm, and the elastic sealing piece is fitted on the bottom wall of the T-shaped rubber ring with zero pressure and seals the air hole, which is used to control the switch of the air hole. The elastic sealing piece is coaxially arranged with the positioning ring, and the elastic connecting wire is evenly distributed between the positioning ring and the elastic sealing piece. When the air flow is sprayed on the elastic sealing piece, the elastic connecting wire controls the directional opening of the elastic sealing piece through elastic deformation. When no air hole is sprayed on the elastic sealing piece, the elastic connecting wire controls the directional closing of the elastic sealing piece through elastic deformation, so that the elastic sealing piece and the T-shaped rubber ring are re-fitted.

[0005] Furthermore, in the aforementioned dropper-use diaphragm one-way valve type antibacterial filter, the elastic connecting wire is arc-shaped, and the two ends of the elastic connecting wire are respectively arranged on the inner wall of the positioning ring and the outer wall of the elastic sealing piece, and the center of the elastic connecting wire is concentric with the center of the elastic sealing piece.

[0006] Furthermore, the aforementioned dropper uses a diaphragm one-way valve type bacteria-blocking filter, wherein the bacteria-blocking filter membrane is made of PTFE material, the filtration accuracy of the bacteria-blocking filter membrane is 0.2μm, the one-way diaphragm is injection molded by TPE material, the diameter of the elastic sealing piece in the one-way diaphragm is 2~3mm, the upper and lower thicknesses of the elastic connecting wire and the left and right widths of the arc segment are the same, both of which are 0.18~0.22mm, the arc length of the elastic connecting wire is 1.2~1.25mm, and the central angle is 45°.

[0007] Furthermore, the aforementioned diaphragm one-way valve type antibacterial filter for the dropper is provided with an annular groove on the bottom wall of the T-shaped rubber ring, and a positioning convex ring is provided on the top wall of the elastic sealing piece. When the elastic sealing piece is fitted on the T-shaped rubber ring at zero pressure, the positioning convex ring is inserted into the annular groove.

[0008] Furthermore, in the aforementioned dropper, the diaphragm one-way valve type bacteria-blocking filter, wherein the bottom wall of the elastic sealing piece is a protruding arched pressure-bearing wall, the arched pressure-bearing wall is coaxial with the elastic sealing piece, the maximum diameter of the arched pressure-bearing wall is larger than the diameter of the pore, and a trumpet-shaped buffer groove is recessed at the center position of the top wall of the elastic sealing piece, and the maximum diameter of the trumpet-shaped buffer groove is smaller than the aperture of the pore.

[0009] Further, in the above-mentioned diaphragm one-way valve type bacteria-proof filter for a dropper, a weight-reducing process groove is provided at the vertex of the arched pressure-receiving wall.

[0010] Further, in the above-mentioned diaphragm one-way valve type bacteria-proof filter for a dropper, a retaining ring is protrudingly provided on the inner side wall of the installation groove. When the positioning ring is clamped in the installation groove, the outer side wall of the positioning ring abuts against the inner side wall of the installation groove, the top wall of the positioning ring abuts against the bottom wall of the T-shaped rubber ring, and the bottom wall of the positioning ring abuts against the retaining ring.

[0011] The above-mentioned air permeability comparison test method uses a bacteria-proof filter without a one-way diaphragm and the above-mentioned diaphragm one-way valve type bacteria-proof filter for a dropper, and the steps are as follows: S1. Assemble the test device, and connect an oil-water separator, a pressure reducing valve, a fine tuning valve, a gas flow sensor, an intelligent digital pressure gauge and a mounting head in sequence through an air pipe. The oil-water separator is connected to a compressed air gas source through an air pipe; S2. Calibrate the test device. The mounting head leads to the external environment. Then, open the compressed air gas source. After the compressed air passes through the drying effect of the oil-water separator, it can remain dry. Through the adjustment of the pressure reducing valve and the fine tuning valve, the flow rate of the compressed air in the air pipe is kept constant. The gas flow sensor shows that the air flow is constantly maintained at Q ml / min, and the gas is directly discharged into the air from the mounting head. The pressure value displayed on the intelligent digital pressure gauge is 0 kPa; S3. Calibrate the bacteria-proof filter. Keep the gas flow rate in S2. Install multiple bacteria-proof filters without a one-way diaphragm on the mounting head in sequence. Observe and record the gas flow rate in the gas flow sensor and the pressure value in the intelligent digital pressure gauge, and then select the bacteria-proof filters with the same gas flow rate and pressure value; S4. Classify the bacteria-proof filters. Prepare an injection solution. Divide the bacteria-proof filters selected in S3 into five groups. The first group of bacteria-proof filters are not treated and kept dry. The second group of bacteria-proof filters are in contact with the injection solution for 12 hours. The third group of bacteria-proof filters are in contact with the injection solution for 48 hours. The fourth group of bacteria-proof filters are in contact with the injection solution for 72 hours. A one-way diaphragm is provided in the fifth group of bacteria-proof filters, and then they are in contact with the injection solution for 72 hours. When the bacteria-proof filters are in contact with the injection solution, the bottom is immersed in the injection solution, and the injection solution will not overflow from the top of the T-shaped rubber ring onto the bacteria-proof filter membrane; S5. Start the test. Open the compressed air gas source in S1 and adjust the gas flow rate to the same gas flow rate Q ml / min as in S2. At this time, the pressure value on the intelligent digital pressure gauge is 0 kPa. Install the bacteria-proof filter in the first group on the mounting head to obtain a gas flow rate of Q 1 ml / min and a pressure value of F 1kPa, install the bacteria - resistant filter in the second group on the mounting head to obtain the gas flow rate Q 2 ml / min and the pressure value F 2 kPa, install the bacteria - resistant filter in the third group on the mounting head to obtain the gas flow rate Q 3 ml / min and the pressure value F 3 kPa, install the bacteria - resistant filter in the fourth group on the mounting head to obtain the gas flow rate Q 4 ml / min and the pressure value F 4 kPa, install the bacteria - resistant filter in the fifth group on the mounting head to obtain the gas flow rate Q 5 ml / min and the pressure value F 5 kPa; S6. Comparison results. First, compare the bacteria - resistant filters in the first to fourth groups to obtain the following results: flow rate: Q 1 >Q 2 >Q 3 >Q 4 , pressure value: F 1 <F 2 <F 3 <F 4 , indicating that the longer the contact time between the bacteria - resistant membrane in the bacteria - resistant filter and the injection solution, the greater the resistance of the bacteria - resistant membrane and the smaller the gas flow rate. Then, compare the bacteria - resistant filter in the fifth group with the bacteria - resistant filters in the first and fourth groups to obtain the following results: flow rate: Q 5 =Q 1 >Q 4 , pressure value: F 5 >F 1 <F 4 , indicating that after setting the one - way diaphragm, the resistance will increase when the one - way diaphragm is opened, but the gas flow rate will not decrease. This shows that when the bacteria - resistant filter with a one - way diaphragm is in contact with the injection solution, the one - way diaphragm can effectively prevent the injection solution from contacting the bacteria - resistant membrane and keep the bacteria - resistant membrane dry.

[0012] Further, for the aforementioned air permeability comparison test method, the mounting head includes: a rod body, in which a ventilation hole penetrating the rod body is provided, and a tracheal hole communicating with the ventilation hole is provided at the upper end of the rod body. The trachea in the test device is inserted into the tracheal hole and is sealed and fitted with the tracheal hole. The small - diameter end of the T - shaped rubber ring in the bacteria - resistant filter is sealed and clamped in the ventilation hole, and the lower end wall of the rod body is sealed and fitted on the upper top wall of the large - diameter end of the T - shaped rubber ring; in S4, install the bacteria - resistant filter that needs to be in contact with the injection solution on the mounting head and then contact it with the injection solution.

[0013] Further, for the aforementioned air permeability comparison test method, the injection solution in S4 is 0.9% NaCl injection solution.

[0014] The advantages of the present invention are as follows: The air holes can be blocked by the one-way diaphragm, so as to protect the bacteria-blocking filter membrane located in the air holes from contacting the liquid medicine in the drip bottle again. In this way, the pores in the bacteria-blocking filter membrane will not be blocked, and the hydrophobicity of the bacteria-blocking filter membrane will not be damaged, maintaining the complete hydrophobicity and air permeability. Moreover, the elastic sealing piece in the one-way diaphragm and the T-shaped rubber ring are in zero-pressure fit, and the pressure generated during gas reflux can push open the elastic sealing piece in the one-way diaphragm, so that the gas can reflux into the bottle body, without affecting the gas reflux efficiency. Brief Description of the Drawings

[0015] Figure 1 is a schematic structural diagram of the diaphragm one-way valve type bacteria-blocking filter for a drip device according to the present invention.

[0016] Figure 2 is Figure 1 a schematic cross-sectional structural diagram when the elastic sealing piece in the one-way diaphragm and the T-shaped rubber ring are in fit in

[0017] Figure 3 is Figure 1 a schematic cross-sectional structural diagram when the elastic sealing piece in the one-way diaphragm and the T-shaped rubber ring are separated in

[0018] Figure 4 is Figure 2 a schematic three-dimensional structural diagram of the one-way diaphragm in

[0019] Figure 5 is Figure 2 a schematic three-dimensional structural diagram of the one-way diaphragm in another direction in

[0020] Figure 6 is a schematic structural diagram of the test device used in the air permeability comparison test method according to the present invention.

[0021] Figure 7 is Figure 6 a schematic structural diagram of the mounting head in

[0022] Figure 8 is a static stress analysis diagram of the one-way diaphragm. Detailed Embodiments

[0023] The technical solution of the present invention will be further described below in conjunction with the drawings and preferred embodiments.

[0024] As Figures 1 to 5As shown in the figure, the diaphragm one-way valve type bacteria-blocking filter for a dropper of the present invention includes: a bacteria-blocking filter membrane 1 with hydrophobicity. The bacteria-blocking filter membrane 1 is made of PTFE material, and the filtration accuracy of the bacteria-blocking filter membrane 1 is 0.2 μm. A T-shaped rubber ring 2 is injection-molded and compounded on the outer side of the bacteria-blocking filter membrane 1. An air hole 21 penetrating through the T-shaped rubber ring 2 is axially arranged in the T-shaped rubber ring 2. The bacteria-blocking filter membrane 1 is horizontally placed in the large-diameter end of the T-shaped rubber ring 2 and blocks the air hole 21. In this embodiment, six through holes 24 are also evenly distributed in a circumferential direction on the T-shaped rubber ring 2, and the bacteria-blocking filter membrane 1 is also horizontally placed in these six through holes 24. The molding method between the T-shaped rubber ring 2 and the bacteria-blocking filter membrane 1 can refer to the continuous molding production line and its molding process of the bacteria-removing filter membrane assembly in a dropper with the authorization number: CN117140848B. These six through holes 24 are only for auxiliary use. When the bacteria-blocking filter is installed in the dropper, the valve body in the dropper will block these six through holes 24 in the bacteria-blocking filter, and only the air hole 21 plays a role in reflux. Moreover, since the T-shaped rubber ring 2 is injection-molded on the bacteria-blocking filter membrane 1, during the injection molding process, the T-shaped rubber ring 2 will block the bacteria-blocking filter membrane 1 in the air hole 21 from the bacteria-blocking filter membrane 1 in the through holes 24. That is to say, the bacteria-blocking filter membrane 1 in the through holes 24 is not connected to the bacteria-blocking filter membrane 1 in the air hole 21. After the bacteria-blocking filter membrane 1 in the through holes 24 comes into contact with the liquid medicine, the liquid medicine will not spread to the bacteria-blocking filter membrane 1 in the air hole 21. The connection structure between the bacteria-blocking filter and the valve body can refer to an air-blocking type sterile drip bottle capable of externally treating residual liquid with the authorization number: CN118415813B.

[0025] An installation groove 22 is downwardly extended on the T-shaped rubber ring 2. A retaining ring 221 is protrudingly arranged on the inner side wall of the installation groove 22. A one-way diaphragm 3 is clamped in the installation groove 22. The one-way diaphragm 3 is injection-molded from TPE material. The one-way diaphragm 3 includes: an integrally formed positioning ring 31, an elastic sealing sheet 32 and elastic connecting wires 33. The positioning ring 31 is clamped in the installation groove 22 to provide a rigid support for the one-way diaphragm 3. The outer side wall of the positioning ring 31 abuts against the inner side wall of the installation groove 22. The top wall of the positioning ring 31 abuts against the bottom wall of the T-shaped rubber ring 2. The bottom wall of the positioning ring 31 abuts against the retaining ring 221 to limit the positioning ring 31. The elastic sealing sheet 32 is coaxially arranged with the positioning ring 31. The elastic sealing sheet 32 is in zero-pressure fit with the bottom wall of the T-shaped rubber ring 2 and seals the air hole 21 for controlling the opening and closing of the air hole 21. The elastic sealing sheet 32 and the T-shaped rubber ring 2 can approach each other under the elastic support of the elastic connecting wires 33 to achieve zero-pressure fit. A circular clamping groove 23 is arranged on the bottom wall of the T-shaped rubber ring 2. A positioning convex ring 321 is arranged on the top wall of the elastic sealing sheet 32. When the elastic sealing sheet 32 is in zero-pressure fit with the T-shaped rubber ring 2, the positioning convex ring 321 is snapped into the circular clamping groove 23 to improve the fitting stability and sealing performance between the elastic sealing sheet 32 and the T-shaped rubber ring 2. The bottom wall of the elastic sealing sheet 32 is an arched pressure-receiving wall 322 protruding. The arched pressure-receiving wall 322 is coaxial with the elastic sealing sheet 32. The maximum diameter of the arched pressure-receiving wall 322 is larger than the aperture of the air hole 21. A weight-reducing process groove 323 is arranged at the vertex of the arched pressure-receiving wall 322 to prevent the one-way diaphragm 3 from protruding excessively and looking unsightly after being installed in the installation groove 22 of the T-shaped rubber ring 2. A trumpet-shaped buffer groove 324 is recessed at the center position of the top wall of the elastic sealing sheet 32. The maximum diameter of the trumpet-shaped buffer groove 324 is smaller than the aperture of the air hole 21. When the elastic sealing sheet 32 is deformed by the airflow and pushed open, the trumpet-shaped buffer groove 324 provides a deformation space for the elastic sealing sheet 32 by depression or expansion, reducing the deformation fatigue of the elastic sealing sheet 32. The elastic connecting wires 33 are circumferentially and uniformly distributed between the positioning ring 31 and the elastic sealing sheet 32. When the airflow passes through the air hole 21 and blows on the elastic sealing sheet 32, the elastic connecting wires 33 control the elastic sealing sheet 32 to open directionally through elastic deformation. When there is no airflow passing through the air hole 21 and blowing on the elastic sealing sheet 32, the elastic connecting wires 33 control the elastic sealing sheet 32 to close directionally through elastic deformation, so that the elastic sealing sheet 32 is re-fitted with the T-shaped rubber ring 2.

[0026] The elastic connecting wire 33 is in an arc shape, and the two ends of the elastic connecting wire 33 are respectively arranged on the inner wall of the positioning ring 31 and the outer wall of the elastic sealing piece 32. The center of the elastic connecting wire 33 is concentric with the center of the elastic sealing piece 32. The elastic connecting wire 33 arranged concentrically with the elastic sealing piece 32 can make each section of the elastic connecting wire 33 have the same bending arc, and the elastic restoring force is evenly distributed, so that the valve opening pressure of the elastic sealing piece 32 is more stable and there will be no jamming. Moreover, when closing the valve, the concentrically arranged arc-shaped elastic connecting wire 33 can evenly pull the elastic sealing piece 32, so that the elastic sealing piece 32 is automatically centered, avoiding reset offset and poor sealing. Since the elastic connecting wires 33 evenly distributed on the circumference are all arc-shaped, arc-shaped gaps are evenly distributed on the circumference between the elastic sealing piece 32 and the positioning ring 31. When the airflow in the air hole 21 pushes open the elastic sealing piece 32 and flows outward, the airflow will flow along the circumference under the guidance of the arc-shaped gaps, reducing gas turbulence and pressure loss and increasing the airflow velocity.

[0027] After installing the diaphragm one-way valve type bacteria-proof filter described in this application into the dropper, the one-way diaphragm 3 blocks the air hole 21, and the liquid medicine in the bottle body cannot come into contact with the bacteria-proof filter membrane 1 in the air hole 21, so that the bacteria-proof filter membrane 1 in the air hole 21 can remain dry. When dripping the liquid, the liquid medicine pressure will be applied to the elastic sealing piece 32. Without the arched pressure-receiving wall 322, the force received by the elastic sealing piece 32 is uneven, and it is easy to have a situation where the pressure is large on one side and small on the other side. The elastic sealing piece 32 is prone to warping, resulting in the contact between the liquid medicine and the bacteria-proof filter membrane 1 in the air hole 21. When the arched pressure-receiving wall 322 is provided on the elastic sealing piece 32, the arched pressure-receiving wall 322 will evenly disperse the pressure to the entire elastic sealing piece 32, so that the elastic sealing piece 32 is evenly pressed. Since the maximum diameter of the arched pressure-receiving wall 322 is larger than the aperture of the air hole 21, the force that evenly disperses the pressure by the arched pressure-receiving wall 322 can act on the elastic sealing piece 32 that fits with the T-shaped rubber ring 2 outside the air hole 21, ensuring the sealing performance of the elastic sealing piece 32 blocking the air hole 21. When the dripping of the liquid is completed, the reflux air is separated from the residual liquid medicine and then blows on the elastic sealing piece 32 through the air hole 21. Since the elastic sealing piece 32 and the T-shaped rubber ring 2 are in zero-pressure fit, the elastic sealing piece 32 will open after being blown by the reflux air and then enter the bottle body. Since the elastic sealing piece 32 in the one-way diaphragm 3 blocks the air hole 21, the bacteria-proof filter membrane 1 in the air hole 21 will not come into contact with the liquid medicine and be blocked, and thus the gas reflux efficiency will not be affected. When the dripping bottle is inverted for air return, the reflux gas is evenly discharged from the periphery of the elastic sealing piece 32, which not only pushes away the liquid medicine around the elastic sealing piece 32, but also forms an annular bubble around the elastic sealing piece 32. When there is no air flow in the air hole 21 to push the elastic sealing piece 32 anymore, the elastic sealing piece 32 fits back on the T-shaped rubber ring 2 to block the air hole 21, and the annular bubble will burst only after the elastic sealing piece 32 fits on the T-shaped rubber ring 2, thus preventing the liquid medicine from entering the air hole 21 through the opened elastic sealing piece 32 and coming into contact with the bacteria-proof filter membrane 1 in the air hole 21.

[0028] In this embodiment, the bacteria-proof filter membrane 1 is a PTFE filter membrane (TE type) produced by Cytiva, an independent operating company under Danaher Group. The filtration accuracy of the bacteria-proof filter membrane 1 in this embodiment is 0.2μm, and the bubble point of this type of bacteria-proof filter membrane 1 is 1.29psi. That is to say, the air flow pressure needs to be greater than 1.29psi to pass through the bacteria-proof filter membrane 1 and reflux to the bottle body. For the characteristics of the bacteria-proof filter membrane 1, reference can be made to the "Whatman TM Laboratory Filtration and Separation Product Guide" provided by Cytiva.

[0029] In this embodiment, the one-way diaphragm 3 is injection-molded from TPE material. The diameter of the elastic sealing piece 32 in the one-way diaphragm 3 is 2 - 3 mm, preferably 2.5 mm. The upper and lower thicknesses of the elastic connecting wire 33 and the left and right widths of the arc section are the same, both being 0.18 - 0.22 mm, preferably 0.2 mm. The arc length of the elastic connecting wire 33 is 1.2 - 1.25 mm, preferably 1.24 mm, and the central angle is 45°.

[0030] As Figure 8 shown, after static stress analysis of the one-way diaphragm 3 by finite element analysis software, it can be known that under a pressure of 1 psi, the displacement gap generated by the elastic sealing piece 32 in the one-way diaphragm 3 is 0.003566 mm, that is, 3.566 μm. That is to say, under a pressure of 1 psi, the elastic connecting wire 33 in the one-way diaphragm 3 can undergo elastic deformation, and the reflux air in the air hole 21 can all pass through the bacteria-blocking filter membrane 1 with a filtration accuracy of 0.2 μm. Therefore, the reflux air from the air hole 21 can push open the elastic sealing piece 32 and flow back into the bottle body through the gap between the opened elastic sealing piece 32 and the T-shaped rubber ring 2. This is because the bubble point of the bacteria-blocking filter membrane 1 is 1.29 psi, and the pressure when the reflux air in the air hole 21 passes through the bacteria-blocking filter membrane 1 is greater than 1.29 psi. So the reflux air can push the elastic sealing piece 32 after passing through the bacteria-blocking filter membrane 1 to cause elastic deformation of the elastic connecting wire 33, thereby opening the elastic sealing piece 32. And the pore diameter of the bacteria-blocking filter membrane 1 is 0.2 μm, which is much smaller than the displacement gap of 3.566 μm of the elastic sealing piece 32. So the air can pass through the bacteria-blocking filter membrane 1 and flow back into the bottle body through the gap between the elastic sealing piece 32 and the T-shaped rubber ring 2. When selecting bacteria-blocking filter membranes 1 with other filtration accuracies, the one-way diaphragm 3 is subjected to static stress analysis by finite element analysis software according to the bubble point of the bacteria-blocking filter membrane 1 to obtain the pressure required for elastic deformation of the elastic sealing piece 32 and the elastic connecting wire 33 in the one-way diaphragm 3 at the bubble point of the corresponding bacteria-blocking filter membrane 1. Then, the parameters of the elastic sealing piece 32 and the elastic connecting wire 33 in the one-way diaphragm 3 are corrected according to this pressure. After the correction is completed, a one-way diaphragm 3 suitable for the bacteria-blocking filter membrane 1 with this filtration accuracy can be produced.

[0031] During the production process, in order to test the effect of the bacteria-blocking filter with the one-way diaphragm 3, an air permeability comparison test needs to be carried out. The steps are as follows: S1. Assemble the test device, connect the oil-water separator 4, pressure reducing valve 5, fine adjustment valve 6, gas flow sensor 7, intelligent digital pressure gauge 8 and mounting head 9 in sequence through an air pipe. The oil-water separator 4 is connected to the compressed air source 10 through an air pipe, as Figure 6 、 Figure 7 shown; S2. Calibrate the test device. The mounting head 9 is directly connected to the external environment. Then, turn on the compressed air source 10. After the compressed air is dried by the oil-water separator 4, it can remain dry. Through the adjustment of the pressure reducing valve 5 and the fine adjustment valve 6, the flow rate of the compressed air in the air pipe is kept constant. The gas flow sensor 7 shows that the air flow is constantly maintained at Q ml / min. In this embodiment, the gas flow shown in the gas flow sensor 7 is 70 ml / min. The gas is directly discharged into the air from the mounting head 9, and the pressure value shown on the intelligent digital pressure gauge 8 is 0 kPa, indicating that the air pipe is unobstructed at this time and there are no obstacles hindering the gas flow; S3. Calibrate the bacteria-retaining filter. Keep the gas flow in S2. Install multiple bacteria-retaining filters without the one-way diaphragm 3 on the mounting head 9 in sequence. Observe and record the gas flow in the gas flow sensor 7 and the pressure value in the intelligent digital pressure gauge 8, and then select the bacteria-retaining filters with the same gas flow and pressure value; In this step, when the gas passes through the bacteria-retaining filter without the one-way diaphragm 3, the gas flow is 48 ml / min and the pressure value is 11.8 kPa; S4. Classify the bacteria-retaining filters. Prepare 0.9% NaCl injection solution. Divide the bacteria-retaining filters selected in S3 into five groups. The first group of bacteria-retaining filters is not treated and kept dry. The second group of bacteria-retaining filters is in contact with the injection solution for 12 hours. The third group of bacteria-retaining filters is in contact with the injection solution for 48 hours. The fourth group of bacteria-retaining filters is in contact with the injection solution for 72 hours. A one-way diaphragm 3 is set in the fifth group of bacteria-retaining filters and then in contact with the injection solution for 72 hours. When the bacteria-retaining filters are in contact with the injection solution, the bottom is immersed in the injection solution, and the injection solution will not overflow from the top of the T-shaped rubber ring 2 onto the bacteria-retaining filter membrane 1; S5. Start the test. Turn on the compressed air source 10 in S1 and adjust the gas flow to 70 ml / min. At this time, the pressure value shown on the intelligent digital pressure gauge 8 is 0 kPa. Take one bacteria-retaining filter from each group for testing. Install the bacteria-retaining filter in the first group on the mounting head 9 to obtain the gas flow Q 1 ml / min and the pressure value F 1 kPa. Install the bacteria-retaining filter in the second group on the mounting head 9 to obtain the gas flow Q 2 ml / min and the pressure value F 2 kPa. Install the bacteria-retaining filter in the third group on the mounting head 9 to obtain the gas flow Q 3 ml / min and the pressure value F 3 kPa. Install the bacteria-retaining filter in the fourth group on the mounting head 9 to obtain the gas flow Q 4 ml / min and the pressure value F 4 kPa. Install the bacteria-retaining filter in the fifth group on the mounting head to obtain the gas flow Q5 ml / min and pressure value F 5 kPa; The specific data is shown in the following table:

[0032] S6. Comparison results. First, compare the bacteria-blocking filters of the first group to the fourth group to obtain the following results: Flow rate: Q 1 > Q 2 > Q 3 > Q 4 , Pressure value: F 1 < F 2 < F 3 < F 4 , indicating that the longer the contact time between the bacteria-blocking filter membrane 1 in the bacteria-blocking filter and the injection solution, the greater the resistance of the bacteria-blocking filter membrane 1, and the smaller the gas flow rate; then compare the fifth group of bacteria-blocking filters with the first group and the fourth group of bacteria-blocking filters to obtain the following results: Flow rate: Q 5 = Q 1 > Q 4 , Pressure value: F 5 > F 1 < F 4 , indicating that after setting the one-way diaphragm 3, the resistance will increase when the one-way diaphragm 3 is opened, but the gas flow rate will not decrease. This shows that when the bacteria-blocking filter with the one-way diaphragm 3 is in contact with the injection solution, the one-way diaphragm 3 can effectively prevent the injection solution from contacting the bacteria-blocking filter membrane 1, keep the bacteria-blocking filter membrane 1 dry, and prevent the bacteria-blocking filter membrane 1 from being blocked.

[0033] The mounting head 9 involved in this embodiment is as Figure 7 shown, including: a rod body 91, in which a ventilation hole 92 penetrating the rod body 91 is provided, and an air pipe hole 93 communicating with the ventilation hole 92 is provided at the upper end of the rod body 91. The air pipe in the testing device is inserted into the air pipe hole 93 and is hermetically fitted with the air pipe hole 93. The small-diameter end of the T-shaped rubber ring 2 in the bacteria-blocking filter is hermetically clamped in the ventilation hole 92, and the lower end wall of the rod body 91 is hermetically attached to the upper top wall of the large-diameter end of the T-shaped rubber ring 2 to block the six through holes 24 on the T-shaped rubber ring 2. In step S4, the bacteria-blocking filter that needs to be in contact with the injection solution is installed on the mounting head 9 and then contacted with the injection solution. The injection solution can only contact the bacteria-blocking filter membrane 1 through the bottom of the bacteria-blocking filter, and the injection solution will not overflow from the top of the T-shaped rubber ring 2 to the bacteria-blocking filter membrane 1. In steps S3 and S5, accurate test data can be obtained only after the bacteria-blocking filter is attached to the mounting head 9 to block the six through holes 24.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications or equivalent substitutions can still be made to the specific embodiments of the present invention, and any modification or equivalent substitution that does not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A diaphragm one-way valve type bacteria-blocking filter for a dropper, comprising: The invention relates to a hydrophobic bacteria-blocking filter membrane, wherein a T-shaped rubber ring is injection-molded and compounded on the outer side of the bacteria-blocking filter membrane, wherein an air hole penetrating the T-shaped rubber ring is axially arranged in the T-shaped rubber ring, and the bacteria-blocking filter membrane is horizontally arranged in the large-diameter end of the T-shaped rubber ring and blocks the air hole. The invention is characterized in that: an installation groove is extended downwardly on the T-shaped rubber ring, and a one-way diaphragm is arranged in the installation groove, wherein the one-way diaphragm comprises: an integrally formed positioning ring, an elastic sealing piece and an elastic connecting wire, wherein the positioning ring is clamped in the installation groove to provide rigid support for the one-way diaphragm, and the elastic sealing piece is provided in the installation groove. The sealing piece is fitted on the bottom wall of the T-shaped rubber ring with zero pressure and seals the air hole, and is used to control the opening and closing of the air hole. The elastic sealing piece is coaxially arranged with the positioning ring, and the elastic connecting wire is evenly distributed between the positioning ring and the elastic sealing piece. When the air flow is sprayed on the elastic sealing piece, the elastic connecting wire controls the directional opening of the elastic sealing piece through elastic deformation. When no air hole is sprayed on the elastic sealing piece, the elastic connecting wire controls the directional closing of the elastic sealing piece through elastic deformation, so that the elastic sealing piece and the T-shaped rubber ring are re-fitted.

2. The membrane one-way valve type bacteria-blocking filter for a dropper according to claim 1, characterized in that: The elastic connecting wire is in an arc shape, and the two ends of the elastic connecting wire are respectively arranged on the inner wall of the positioning ring and the outer wall of the elastic sealing piece, and the center of the elastic connecting wire is concentric with the center of the elastic sealing piece.

3. The membrane one-way valve type bacteria-blocking filter for a dropper according to claim 2, characterized in that: The antibacterial filter membrane is made of PTFE material, and the filtration accuracy of the antibacterial filter membrane is 0.2μm. The one-way diaphragm is injection molded by TPE material. The diameter of the elastic sealing piece in the one-way diaphragm is 2-3mm. The upper and lower thicknesses of the elastic connecting wire and the left and right widths of the arc segment are the same, both of which are 0.18-0.22mm. The arc length of the elastic connecting wire is 1.2-1.25mm, and the central angle is 45°.

4. The membrane one-way valve type bacteria-blocking filter for a dropper according to claim 3, characterized in that: An annular groove is arranged on the bottom wall of the T-shaped rubber ring, and a positioning convex ring is arranged on the top wall of the elastic sealing piece. When the elastic sealing piece is pressed against the T-shaped rubber ring with zero pressure, the positioning convex ring is inserted into the annular groove.

5. The membrane one-way valve type bacteria-blocking filter for a dropper according to claim 4, characterized in that: The bottom wall of the elastic sealing piece is a protruding arched pressure wall, which is coaxial with the elastic sealing piece. The maximum diameter of the arched pressure wall is larger than the diameter of the pore. A trumpet-shaped buffer groove is recessed at the center of the top wall of the elastic sealing piece. The maximum diameter of the trumpet-shaped buffer groove is smaller than the aperture of the pore.

6. The membrane one-way valve type bacteria-blocking filter for a dropper according to claim 5, characterized in that: A weight-reducing process groove is arranged at the apex of the arched pressure-bearing wall.

7. The membrane one-way valve type bacteria-blocking filter for a dropper according to claim 1, characterized in that: A stop ring is protruding from the inner wall of the installation groove. When the positioning ring is clamped in the installation groove, the outer wall of the positioning ring abuts against the inner wall of the installation groove, the top wall of the positioning ring abuts against the bottom wall of the T-shaped rubber ring, and the bottom wall of the positioning ring abuts against the stop ring.

8. Air permeability comparison test method, characterized in that: Using a bacteria-blocking filter without a one-way diaphragm and a diaphragm one-way valve type bacteria-blocking filter for a dropper as claimed in any one of claims 1 to 7, the steps are as follows: S1. Assemble the test device, connect the oil-water separator, pressure reducing valve, fine-tuning valve, gas flow sensor, intelligent digital pressure gauge and installation head in sequence through the air pipe, and connect the oil-water separator to the compressed air source through the air pipe; S2. Calibrate the test device, connect the installation head directly to the external environment, and then turn on the compressed air source. The compressed air can remain dry after passing through the oil-water separator. The flow rate of the compressed air in the air pipe is kept constant through the regulation of the pressure reducing valve and the fine-tuning valve. The gas flow sensor shows that the air flow is constant at Qml / min. The gas is directly discharged from the installation head into the air, and the pressure value displayed on the intelligent digital pressure gauge is 0kPa; S3, calibrate the antibacterial filter, maintain the gas flow in S2, install multiple antibacterial filters without one-way diaphragms on the mounting head in sequence, observe and record the gas flow in the gas flow sensor and the pressure value in the intelligent digital pressure gauge, and then select the antibacterial filters with the same gas flow and pressure values; S4, classify the bacteria-blocking filters, prepare the injection solution, divide the bacteria-blocking filters selected in S3 into five groups, the bacteria-blocking filters in the first group are not treated in any way and are kept dry, the bacteria-blocking filters in the second group are in contact with the injection solution for 12 hours, the bacteria-blocking filters in the third group are in contact with the injection solution for 48 hours, the bacteria-blocking filters in the fourth group are in contact with the injection solution for 72 hours, and a one-way membrane is set in the fifth group of sterilizing filters, which are then in contact with the injection solution for 72 hours. When the bacteria-blocking filters are in contact with the injection solution, the bottoms are immersed in the injection solution, and the injection solution will not overflow from the top of the T-shaped rubber ring to the bacteria-blocking filter membrane; S5, start the test, turn on the compressed air source in S1 and adjust the gas flow rate to the same gas flow rate Qml / min as in S2. At this time, the pressure value on the intelligent digital pressure gauge is 0kPa. Install the antibacterial filter in the first group on the mounting head to obtain a gas flow rate Q1ml / min and a pressure value F1kPa. Install the antibacterial filter in the second group on the mounting head to obtain a gas flow rate Q2ml / min and a pressure value F2kPa. Install the antibacterial filter in the third group on the mounting head to obtain a gas flow rate Q3ml / min and a pressure value F3kPa. Install the antibacterial filter in the fourth group on the mounting head to obtain a gas flow rate Q4ml / min and a pressure value F4kPa. Install the antibacterial filter in the fifth group on the mounting head to obtain a gas flow rate Q5ml / min and a pressure value F5kPa. S6. Compare the results. First, compare the first to fourth groups of bacteria-blocking filters, and get the following results: flow rate: Q1>Q2>Q3>Q4, pressure value: F1<F2<F3<F4, which means that the longer the contact time between the bacteria-blocking filter membrane and the injection liquid, the greater the resistance of the bacteria-blocking filter membrane and the smaller the gas flow rate. Then compare the fifth group of bacteria-blocking filters with the first and fourth groups of bacteria-blocking filters, and get the following results: flow rate: Q5=Q1>Q4, pressure value: F5>F1<F4, which means that after setting the one-way diaphragm, the resistance will increase when the one-way diaphragm is opened, but the gas flow rate will not be reduced. This shows that when the bacteria-blocking filter equipped with a one-way diaphragm comes into contact with the injection liquid, the one-way diaphragm can effectively prevent the injection liquid from contacting the bacteria-blocking filter membrane, so that the bacteria-blocking filter membrane remains dry.

9. The air permeability comparison test method according to claim 8, characterized in that: The mounting head comprises: a rod body, a vent hole penetrating the rod body is arranged in the rod body, a tracheal hole connected to the vent hole is arranged at the upper end of the rod body, the trachea in the test device is inserted into the tracheal hole and sealed with the tracheal hole, the small diameter end of the T-shaped rubber ring in the antibacterial filter is sealed and clamped in the vent hole, and the lower end wall of the rod body is sealed and fitted on the upper top wall of the large diameter end of the T-shaped rubber ring; in S4, the antibacterial filter that needs to contact with the injection liquid is installed on the mounting head, and then contacts with the injection liquid.

10. The air permeability comparison test method according to claim 8, characterized in that: The injection in S4 is 0.9% NaCl injection.

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