A medical filter and a method of making the same

Abstract

The application relates to the technical field of filtering devices, in particular to a medical filter and a preparation method thereof. The filter comprises a shunt assembly, an inlet liquid filter membrane and an outlet liquid filter membrane. The inlet liquid filter membrane and the outlet liquid filter membrane are arranged on the two sides of the shunt assembly and form a first liquid passing cavity supported by the shunt assembly. The inlet liquid filter membrane and the outlet liquid filter membrane are arranged on the two sides of the shunt assembly to form two-stage filtering channels. The liquid medicine is primarily filtered through the inlet liquid filter membrane, uniformly dispersed through the cavity supported by the shunt assembly, and secondarily filtered through the outlet liquid filter membrane. The double-membrane structure is filtered twice, the impurity interception capacity is obviously enhanced, and the stability of the filter during intermittent work is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of filtration device technology, and in particular to a medical filter and its preparation method. Background Technology

[0002] Filtration equipment is widely used in the medical field, covering air purification, water treatment, pharmaceutical production, and many other areas. In intravenous infusions, medical filters are used to ensure the safe delivery of medications and prevent particles or air bubbles from entering the patient's bloodstream.

[0003] Chinese Patent Publication No. CN113117397B discloses a medical filter for infusion, comprising a main body and a side cover, with an inner cavity formed between the main body and the side cover. The inner cavity includes a first chamber and a second chamber. The first chamber is defined by the side cover, the main body, and a filter membrane. The second chamber is defined by the main body and the filter membrane. The main body has a first channel for fluid inflow and a second channel for fluid outflow at its two ends. The filter membrane mounting frame is located inside the main body. A flow-diverting cavity is provided between the filter membrane mounting frame and the outlet of the first channel. A flow-diverting portion is provided within the flow-diverting cavity, aligned with the outlet of the first channel. The flow-diverting portion is fixed to the filter membrane mounting frame and protrudes towards the side cover relative to the filter membrane mounting frame. The flow-diverting cavity communicates with the first chamber, and the second channel communicates with the second chamber. The objective of this invention is to provide a medical filter for infusion that achieves efficient and precise filtration.

[0004] Chinese Patent Publication No. CN214319316U discloses a medical suction filter with an offset outlet tube, relating to the field of medical devices. The filter includes a housing and an outlet tube. The outlet tube is located on one side of the bottom of the housing. The inner cavity of the outlet tube communicates with the inner cavity of the housing, and the axis of the inner cavity of the outlet tube forms an angle with the axis of the inner cavity of the housing. The end of the outlet tube away from the housing extends away from the axis of the inner cavity. This offset arrangement brings the outlet tube closer to the side wall of the housing, reducing the obstruction between the side wall of the housing and the inner wall of the outlet tube. The outlet tube extends continuously away from the axis of the inner cavity, allowing blood to be quickly discharged from the filter under gravity, preventing clotting.

[0005] Chinese Patent Publication No. CN213790973U discloses a filter comprising an inlet, an outlet, a top cover, a bottom cover, and a filter plate sealed and fixed between the top cover and the bottom cover. The filter plate includes a membrane support plate and a first filter membrane and a second filter membrane respectively sealed and fixed to a first surface and a second surface of the membrane support plate. The first surface and the second surface of the membrane support plate are respectively formed with a first through-hole and a second through-hole, and a confluence channel formed between the first surface and the second surface, communicating with the first through-hole, the second through-hole, and the outlet. The first filter membrane and the second filter membrane respectively cover the first through-hole and the second through-hole. The raw material fluid flows in through the inlet, is filtered by the first filter membrane and the second filter membrane, and the clean filtrate passes through the first through-hole and the second through-hole, flows into the confluence channel, and finally flows to the outlet and is discharged. In this filter, the membrane support plate has a simple structure, is easy to manufacture, is easy to assemble, and can provide a larger filtration area and a simple fluid flow path.

[0006] However, the filter membranes of the aforementioned medical filters are all single-layer structures, resulting in poor filtration performance. Furthermore, prolonged or intermittent operation can lead to poor liquid flow, affecting the stability of the filter during operation. Summary of the Invention

[0007] Therefore, the present invention provides a medical filter and its preparation method to overcome the problems that the filter membranes of existing medical filters are all single-layer structures, resulting in poor filtration effect. At the same time, during long-term or intermittent operation, the liquid flow effect of the filter is poor, affecting the stability of the filter during operation.

[0008] To achieve the above objectives, on the one hand, the present invention provides a medical filter, wherein the filter chamber is configured as a disc-shaped structure including an input chamber and an output chamber, the filter chamber is arranged longitudinally, an inlet is provided above the input chamber, and an outlet is provided below the output chamber; and a flow divider and a flow plate are disposed between the input chamber and the output chamber.

[0009] Used to seal the inlet and outlet covers of the filter;

[0010] The flow divider is wrapped with an inlet filter membrane and an outlet filter membrane on both sides, forming a first liquid passage cavity supported by the flow divider, which is used to receive the liquid filtered by the inlet filter membrane.

[0011] The liquid outlet filter membrane and the flow plate form a second liquid passage cavity to receive the liquid filtered by the liquid outlet filter membrane. The second liquid passage cavity is separated by the flow splitting component and the flow plate, dividing the second liquid passage cavity into an upper part and a lower part.

[0012] For the aforementioned effluent filter membrane

[0013] In response to filtration, the effluent filter membrane filters the liquid in the first liquid passage cavity from the upper part of the second liquid passage cavity;

[0014] In response to filtration stopping, the gas that was not completely discharged when the liquid outlet filter membrane stopped blocking the lower part of the second liquid passage cavity.

[0015] Furthermore, the diversion component includes several sets of support structures configured with different lengths;

[0016] The major axis of each supporting structure is perpendicular to the plane corresponding to the flow plate;

[0017] For each support structure that is at the same vertical distance from the liquid inlet, its length is the same;

[0018] The inlet filter membrane and the outlet filter membrane are supported by the support structure and form the first liquid passage cavity.

[0019] Furthermore, the flow plate is disposed in the output chamber and has flow holes, which are located on the side near the liquid inlet;

[0020] The flow passage is located at the upper part of the second liquid passage cavity, and the flow passage itself is not separated by the partition.

[0021] Furthermore, the input chamber is used to receive the filtered liquid, and the inlet filter membrane forms an inclined surface with the diversion component to increase the filtration area;

[0022] The liquid-inlet filter membrane performs one filtration of the liquid during the filtration process.

[0023] During the first filtration, the input chamber gradually fills with liquid and flows into the first liquid-passing cavity.

[0024] Furthermore, the inclined surface is supported by the support structure and formed by the height difference of each support structure. The central region of the liquid inlet filter membrane is higher than the edge region, forming a raised structure that protrudes towards the input cover.

[0025] Furthermore, the flow holes are concentrated in the upper central area of ​​the flow plate, and all the flow holes are located above the partition.

[0026] The output cover and the flow plate form an output chamber, and the output chamber connects the second liquid-passing cavity and the liquid outlet.

[0027] Furthermore, the effluent filter membrane filters the liquid that has been filtered by the influent filter membrane for secondary filtration;

[0028] During the filtration process, the upper part of the second liquid-passing cavity receives the filtered liquid and flows into the output chamber through the flow-through hole.

[0029] Furthermore, the inlet filter membrane and the outlet filter membrane are configured as nuclear pore membranes.

[0030] On the other hand, a method for preparing a medical filter includes:

[0031] Fabrication of the outer casing, flow plate, and sealing cap; and

[0032] This forms a filtration assembly consisting of an outlet filter membrane, a flow splitter, and an inlet filter membrane.

[0033] Assemble the filter;

[0034] Forming the filter group includes:

[0035] Step S1: Cut the liquid outlet filter membrane and the liquid inlet filter membrane, and press the edges of the liquid outlet filter membrane and the liquid inlet filter membrane together to form a filter bag;

[0036] Step S2, open the filter bag and insert the diversion assembly into the filter bag; and

[0037] Adjust the filter bag so that the opening of the filter bag is at the preset opening;

[0038] Step S3: Press the filter assembly against the flow plate to press the edge of the filter bag against the outer shell, with the opening located between the flow plate and the diversion assembly;

[0039] The preset opening is arranged parallel to the support structure of the diversion component, and the opening size is no greater than 1 / 3 of the perimeter of the diversion component.

[0040] Furthermore, in step S1, when cutting the liquid outlet filter membrane, the liquid outlet filter membrane is cut into an ellipse shape, the minor axis of which is not less than the diameter of the flow plate, the major axis of which is not less than the diameter of the outer shell, and not greater than 1.5 times the horizontal projected diameter of the diversion component.

[0041] When cutting the liquid inlet filter membrane, the liquid inlet filter membrane is cut into a circle, the diameter of which is not less than the diameter of the outer shell and not greater than the long axis of the liquid outlet filter membrane;

[0042] During the formation of the filter bag, the liquid inlet filter membrane is pressed against the liquid outlet filter membrane from the side corresponding to the liquid outlet filter membrane.

[0043] The preset opening is located at the corresponding position on the long axis of the liquid outlet filter membrane;

[0044] When assembling the filter, the filter assembly is configured into a disc-shaped filter assembly after being supported by the flow divider, and the filter assembly is pressed against the flow plate, pressing the edge of the liquid inlet filter membrane into the filter housing to complete the assembly.

[0045] Furthermore, in step S2, to accommodate the several support structures of different lengths provided on the diversion assembly, an opening is made at the position of the long axis of the effluent filter membrane, allowing the entire diversion assembly to be placed in the corresponding position. Simultaneously,

[0046] Because the size of the filter bag is slightly larger than that of the diversion assembly, the supporting structures of the diversion assembly can support several partitioned areas in the filter bag to form a first liquid passage cavity inside the filter bag, and form the upper and lower parts of the second liquid passage cavity by pressing it against the flow plate.

[0047] Furthermore, the following steps are also included in the filter assembly process:

[0048] Clean air is introduced into the filter assembly through its opening.

[0049] Once the filter assembly inflates, press it into the corresponding position on the outer casing.

[0050] Compared with existing technologies, the advantages of this invention lie in the fact that by separately placing the inlet filter membrane and the outlet filter membrane on both sides of the diversion assembly, a two-stage filtration channel is formed. The drug solution is first pre-filtered by the inlet filter membrane, then uniformly dispersed through the cavity supported by the diversion assembly, and finally finely filtered by the outlet filter membrane. The dual-membrane structure significantly enhances the impurity retention capacity and reduces the risk of clogging.

[0051] Furthermore, the support structure of the diversion component is designed to create a height difference, resulting in a dome-shaped inclined surface on the influent filter membrane, with a higher center and lower edges. This structure significantly increases the contact area between the liquid and the filter membrane, while guiding the fluid to diffuse naturally, reducing turbulence and dead zones, and ensuring filtration uniformity.

[0052] Furthermore, the support structure precisely supports the double-layer filter membrane to form a stable first liquid-passing cavity, while the second liquid-passing cavity, enclosed by the flow plate and the outlet filter membrane, is divided into upper and lower parts. This design maintains the cavity shape without deformation, and with the flow holes concentrated in the upper central area, it achieves directional flow guidance and avoids liquid stagnation.

[0053] Compared with the prior art, the beneficial effects of the present invention are that the filter assembly adopts an integrated structure to reduce the number of assembly parts, while the indentation and support structure fit tightly to improve the sealing effect and reduce the risk of leakage.

[0054] Meanwhile, to solve the problem of using only a single-layer filter membrane for filtration in the prior art, the present invention sets up a filter group with a double-layer filter membrane in a form that is far away from the filter box sealing cover. At the same time, to avoid the problem of filter membrane sticking and the resulting decrease in filtration effect and filtration efficiency, the present invention sets up a corresponding flow diversion component to avoid the problem of filter membrane sticking.

[0055] However, due to the diversion component, tiny air bubbles from the liquid medicine are filtered by the filter membrane and adsorbed at the inlet or outlet filter membrane, affecting the liquid output effect. This invention, by setting several inclined filter surfaces, can block these air bubbles near the bottom of the filter, effectively avoiding the problem of poor liquid output caused by trapped air.

[0056] To address the issue that in existing technologies, poor liquid flow in filters during prolonged or intermittent operation can affect the stability of the filters during operation, this application incorporates a second liquid-passing cavity at its lower part as a buffer, and utilizes the opening in the filter assembly to create a movable chamber that communicates with the first liquid-passing cavity.

[0057] During the intermittent period, some air is stored in the lower part of the second liquid-passing cavity. When the filter is restarted, the second liquid-passing cavity intercepts some air bubbles, preventing them from entering the upper part of the first liquid-passing cavity, which can effectively improve the filtration efficiency when the filter is restarted. Attached Figure Description

[0058] Figure 1 This is a schematic diagram of the structure of the medical filter of the present invention;

[0059] Figure 2 This is a cross-sectional view of the filter according to an embodiment of the present invention;

[0060] Figure 3 This is a top view of the shunt component according to an embodiment of the present invention;

[0061] Figure 4 This is a schematic diagram of the fluid flow according to an embodiment of the present invention;

[0062] Figure 5 This is a schematic diagram of the filter membrane workflow according to an embodiment of the present invention;

[0063] Figure 6 This is a schematic diagram of the filter membrane termination process according to an embodiment of the present invention;

[0064] Figure 7 This is a flowchart illustrating the preparation method of the medical filter of the present invention;

[0065] Figure 8 This is a schematic diagram of the assembly groove in an embodiment of the present invention;

[0066] Wherein: 1, filter chamber; 11, input chamber; 111, liquid inlet; 12, output chamber; 121, liquid outlet; 13, first liquid passage cavity; 14, second liquid passage cavity; 141, upper part of the second liquid passage cavity; 142, lower part of the second liquid passage cavity; 15, outer shell groove; 2, flow plate; 21, flow hole; 22, flow plate groove; 3, flow divider assembly; 4, filter membrane; 41, inlet filter membrane; 42, outlet filter membrane; 5, input cover; 6, output cover; 61, vent hole. Detailed Implementation

[0067] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0068] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0069] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0070] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0071] Please see Figure 1 As shown, this is a schematic diagram of the structure of the medical filter of the present invention. In the figure, the filter chamber 1 is provided with a disc-shaped structure and is arranged vertically, including:

[0072] The filter chamber 1 is configured as an input chamber 11 and an output chamber 12. The input chamber 11 has an inlet 111 and the output chamber 12 has an outlet 121.

[0073] A flow splitter 3 is installed between the input chamber 11 and the output chamber 12;

[0074] A flow plate 2 with flow holes 21 is provided;

[0075] The inlet cover 5 and outlet cover 6 are used to seal the filter;

[0076] The feature is that the filter membrane 4 is disposed on both sides of the flow splitting assembly 3, including,

[0077] The liquid inlet filter membrane 41 is installed in the input chamber 11 and forms the input chamber with the input cover 5 and the input chamber 11;

[0078] And, the liquid outlet filter membrane 42 is disposed on the other side of the diversion assembly 3;

[0079] The inlet filter membrane 41 and the outlet filter membrane 42 are respectively disposed on both sides of the diversion component 3, and form a first liquid passage cavity 13 supported by the diversion component 3, which is used to receive the medicine liquid filtered by the inlet filter membrane 41.

[0080] The liquid outlet filter membrane 42 and the flow plate 2 form a second liquid passage cavity 14 to receive the liquid filtered by the liquid outlet filter membrane 42. The second liquid passage cavity 14 is divided into an upper part and a lower part by the flow splitting component 3 and the flow plate 2.

[0081] In response to filtration, the effluent filter membrane 42 filters the liquid in the first liquid cavity 13 at the upper part of the second liquid cavity 14;

[0082] In response to filtration stopping, the liquid outlet filter membrane 42 blocks the gas in the first liquid outlet cavity 13 at the lower part of the second liquid outlet cavity 14.

[0083] By placing the inlet filter membrane 41 and the outlet filter membrane 42 on opposite sides of the flow divider 3, a two-stage filtration channel is formed. The drug solution is first initially filtered by the inlet filter membrane 41, then evenly dispersed through the cavity supported by the flow divider 3, and finally finely filtered by the outlet filter membrane 42. The dual-membrane structure significantly enhances the impurity retention capacity and reduces the risk of clogging.

[0084] Specifically, the diversion component 3 includes several sets of support structures configured with different lengths;

[0085] Among them, each supporting structure is perpendicular to the plane corresponding to the flow plate 2;

[0086] For each support structure that is equidistant from the plane corresponding to the liquid inlet, its length is the same;

[0087] The inlet filter membrane 41 and the outlet filter membrane 42 are supported by a support structure and form the first liquid passage cavity 13.

[0088] Please see Figure 2 As shown, it is a cross-sectional view of the filter according to an embodiment of the present invention. Figure 2 Based on the state shown, the supporting structures on the diversion component 3 have the same dimensions at the same height;

[0089] It is understandable that the supporting structures can be arranged arbitrarily on the plane, as long as the requirement of axisymmetry is met;

[0090] It should be noted that at least one set of support structures must be pressed against the flow plate, and no set of support structures can come into contact with the input cover 5.

[0091] Please see Figure 3 As shown, this is a top view of the shunt component according to an embodiment of the present invention. Please refer to it. Figure 1 Top-down and Figure 3 Check the corresponding options. Figure 1 There are four sets of support structures from top to bottom, corresponding to Figure 3 The structure consists of several supporting structures arranged from top to bottom. Optionally, the second set of supporting structures can be configured as a set of support plates to form a structure like... Figure 1 The partition on the flow plate is under medium pressure;

[0092] During assembly, the cross plate should be pressed as a whole onto the flow plate and the outer casing to form the upper and lower parts of the second flow cavity.

[0093] Under the above conditions, the support structure on the shunt assembly can be replaced with:

[0094] A number of evenly distributed guide vanes, at least one of which is pressed against the flow plate to form a second liquid-passing cavity 14 divided into two sections;

[0095] Several support plates are arranged in a honeycomb pattern, with at least one set of honeycombs pressed against the flow plate.

[0096] Specifically, the flow plate 2 is installed in the output chamber 12, and the flow hole 21 is installed on the side near the liquid inlet 111;

[0097] The liquid outlet filter membrane 42 and the flow plate 2 form a second liquid passage cavity 14, and the second liquid passage cavity 14 is separated by the flow diversion component 3 and the flow plate 2, dividing the second liquid passage cavity 14 into an upper part and a lower part, namely the upper part 141 of the second liquid passage cavity and the lower part 142 of the second liquid passage cavity.

[0098] The flow passage 21 is located at the top and is not separated.

[0099] The support structure of the diversion component 3 creates a height difference, causing the inlet filter membrane 41 to present a dome-shaped inclined surface with a high center and low edges. This structure significantly increases the contact area between the liquid and the filter membrane, while guiding the fluid to diffuse naturally, reducing turbulence and dead zones, and ensuring filtration uniformity.

[0100] Specifically, the input chamber is used to receive the filtered liquid, and the inlet filter membrane 41 forms an inclined surface with the diversion component 3 to increase the contact area between the filter membrane and the liquid and improve the filtration efficiency.

[0101] Specifically, the inclined surface is formed by the height difference of the supporting structure, and the central region of the liquid inlet filter membrane 41 is higher than the edge region, forming a raised structure that protrudes towards the input cover 5.

[0102] Specifically, the flow holes 21 are concentrated in the upper central area of ​​the flow plate 2, and all the flow holes 21 are located above the partition.

[0103] Please cooperate. Figure 1 See Figure 2 As shown in the figure,

[0104] The output cover 6 and the flow plate 2 form an output chamber, which is connected to the second liquid passage cavity 14 and the liquid outlet 121.

[0105] The output cover 6 is also provided with a corresponding exhaust hole 61 to discharge the air in the filter.

[0106] The support structure precisely supports the double-layer filter membrane to form a stable first liquid-passing cavity 13, while the second liquid-passing cavity 14, enclosed by the flow plate 2 and the outlet filter membrane 42, is divided into upper and lower parts. This design maintains the cavity shape without deformation, and with the flow holes 21 concentrated in the upper central area, it achieves directional flow guidance and avoids liquid stagnation.

[0107] Specifically, the inlet filter membrane 41 and the outlet filter membrane 42 are configured as nuclear pore membranes.

[0108] Please see Figure 4 As shown, it is a schematic diagram of the liquid flow in an embodiment of the present invention. In the figure, the liquid entering the filter flows sequentially in the order of A→B→C→D→E.

[0109] Please see Figure 4 The diagram shown is a schematic representation of the filter membrane workflow according to an embodiment of the present invention. Please refer to [link / reference]. Figure 5 Figure (a) shows the liquid inlet flow diagram of the filter membrane process. In the diagram, the liquid flows into the filter from the inlet and flows downward along the filter membrane.

[0110] Please see Figure 5 Figure (b) shows the first filtration diagram of the filter membrane in operation. When the medicine liquid fills the input chamber, the medicine liquid enters the first liquid passage cavity through the inlet filter membrane. The first liquid passage cavity is supported by the diversion component, and the appearance of the inlet filter membrane itself does not change.

[0111] Please see Figure 5Figure (c) shows a schematic diagram of the second filtration process of the filter membrane. In the figure, the first liquid passage cavity is filled with the drug solution. At the same time, the drug solution enters the second liquid passage cavity through the outlet filter membrane. Under the liquid pressure, the outlet filter membrane at the bottom of the second liquid passage cavity is pushed away from the diversion component and pulled by the corresponding outlet filter membrane at the top of the second liquid passage cavity. After the bottom of the second liquid passage cavity is filled, the air in the entire input chamber is concentrated at the top of the second liquid passage cavity.

[0112] Please see Figure 5 Figure (d) shows a schematic diagram of the filter membrane in operation. When the input chamber is completely full, the liquid enters the output chamber through the flow hole. At this time, the liquid is filtered twice by the inlet filter membrane and the outlet filter membrane, and then the air is vented through the second flow cavity to complete the precision filtration.

[0113] Please see Figure 6 As shown, it is a schematic diagram of the filter membrane termination process according to an embodiment of the present invention;

[0114] When the medication stops flowing, the inlet is shut off. At this time, due to the remaining liquid in the infusion tubing, such as... Figure 5 Figure (a) shows the initial diagram of the flow interruption, where the filter is still full of liquid medicine.

[0115] Please see Figure 6 Figure (b) shows a schematic diagram of the middle section of the flow interruption. After a period of time, the liquid in the input chamber and the output chamber is consumed. At this time, the first liquid cavity and the second liquid cavity still contain liquid due to the surface tension of the liquid in the filter membrane.

[0116] Please see Figure 6 Figure (c) shows a schematic diagram of the flow interruption termination. In the figure, the liquid outlet filter membrane corresponding to the lower part of the second liquid passage cavity is adsorbed, returns to the corresponding position in contact with the diversion component, and isolates the lower part of the second liquid passage cavity. At the same time, the liquid corresponding to the upper part of the second liquid passage cavity is no longer replenished after it has flowed out.

[0117] In this state, if the infusion continues, the lower part of the second fluid passage cavity will no longer be filled with air because it is full of medication. At the same time, the air brought in by the medication can be expelled into the upper part of the second fluid passage cavity more quickly.

[0118] Please see Figure 7 As shown, this is a method for preparing the medical filter of the present invention, comprising:

[0119] Fabrication of the outer casing, flow plate, and sealing cap; and

[0120] This forms a filtration assembly consisting of an outlet filter membrane, a flow splitter, and an inlet filter membrane.

[0121] Assemble the filter;

[0122] When forming a filter group, the following are included:

[0123] Step S1: Cut the effluent filter membrane and the influent filter membrane, and press the edges of the effluent filter membrane and the influent filter membrane together to form a filter bag;

[0124] Step S2, open the filter bag and insert the diversion assembly into the filter bag; and

[0125] Adjust the filter bag so that the opening of the filter bag is at the preset opening;

[0126] Step S3: Press the filter assembly against the flow plate to press the edge of the filter bag tightly against the outer shell, with the opening located between the flow plate and the flow distribution assembly;

[0127] The preset opening is set parallel to the support structure of the diversion component, and the opening size is no more than 1 / 3 of the perimeter of the diversion component.

[0128] It should be noted that if the opening is too large, the first liquid passage cavity formed between the inlet and outlet filter membranes will be difficult to seal effectively, and the filter membrane may not function properly during use.

[0129] In step S1, when cutting the effluent filter membrane, the effluent filter membrane is cut into an ellipse shape, with its minor axis not less than the diameter of the flow plate, its major axis not less than the diameter of the outer shell, and not greater than 1.5 times the horizontal projection diameter of the diversion component.

[0130] When cutting the inlet filter membrane, the inlet filter membrane should be cut into a circle with a diameter not less than the diameter of the outer shell and not greater than the major axis of the outlet filter membrane.

[0131] During the formation of the filter bag, the liquid inlet filter membrane is pressed against the liquid outlet filter membrane;

[0132] The pre-set opening is located at the corresponding position on the long axis of the effluent filter membrane;

[0133] When assembling the filter, the filter assembly is configured into a disc-shaped filter assembly after being supported by the diversion component, and the filter assembly is pressed against the flow plate. The edge of the inlet filter membrane is pressed into the filter housing to complete the assembly.

[0134] In step S2, to accommodate the various support structures of different lengths on the diversion assembly, an opening is made at the location of the long axis of the effluent filter membrane, allowing the entire diversion assembly to be placed in the corresponding position. Simultaneously,

[0135] Because the size of the filter bag is slightly larger than that of the diversion assembly, the supporting structures of the diversion assembly can support several partitioned areas in the filter bag to form a first liquid passage cavity inside the filter bag, and form the upper and lower parts of the second liquid passage cavity by pressing it against the flow plate.

[0136] Please see Figure 8As shown, this is a schematic diagram of the assembly groove in an embodiment of the present invention. In this embodiment, for better assembly, the filter assembly can be positioned using the following method.

[0137] Optionally, a horizontal flow plate groove 22 is provided below the flow hole 21 on the flow plate 2, and a longitudinal groove is provided on the outer shell to match the flow plate groove, so as to press the horizontal support structure or support plate in the filter group into the groove, and to use the groove to press the filter membrane on the outside of the support structure or support plate.

[0138] Optionally, a housing groove 15 is provided on the filter chamber 1 of the housing. The depth of the groove is not less than the thickness of the filter membrane and not greater than the difference between the maximum diameter of the filter group and the minimum diameter of the filter chamber 1.

[0139] During assembly, the diversion assembly presses the edge of the inlet filter membrane into the housing groove 15.

[0140] It should be noted that during assembly, since the direction in which the edge of the liquid inlet filter membrane wraps around the flow divider is opposite to the direction of the flow divider's compression, the flow divider should be placed above the filter bag, and the edge of the flow divider should be wrapped around the edge of the liquid inlet filter membrane as much as possible to prevent the liquid inlet filter membrane from slipping off after assembly.

[0141] The following steps are also included in the filter assembly process:

[0142] Clean air is pumped into the filter assembly through its opening.

[0143] Once the filter assembly inflates, press it into the corresponding position on the outer casing.

[0144] The filter assembly is formed by softening a composite membrane and then wrapping it around the flow distribution component 3. Indentations and pleats are created through hot pressing to match the contours of the supporting structure. This one-piece structure reduces the number of assembly parts, while the tight fit between the indentations and the supporting structure improves the sealing effect and reduces the risk of leakage.

[0145] It should be noted that in this plan:

[0146] When preparing the filter membrane, the filter membrane is formed by pressing the base membrane and non-woven fabric together to form a composite membrane. The commonly used substrates are polycarbonate (PC), polyester (PET) or polyethersulfone (PES) film (the thickness is usually 5~20μm).

[0147] Optionally, the above-mentioned substrate can be modified during preparation to enhance its performance.

[0148] It is important to note that the filter assembly should be sterilized before assembly.

[0149] Understandably, nuclear pore membrane materials possess high-precision filtration characteristics. Combined with the clean air filling and final sterilization steps during the manufacturing process, this ensures that the filter membrane is sterile and free from particle shedding. The overall design meets the stringent requirements for biosafety and reliability of medical filters, which will not be elaborated upon here.

[0150] Please see Figure 1 During assembly, a filter assembly consisting of a composite membrane, a flow divider, and a composite membrane, manufactured using the above method, is used. This filter assembly includes an inlet filter membrane 41, a flow divider 3, and an outlet filter membrane 42. At this time, due to the introduction of air, the filter assembly is configured as follows: Figure 2 The shape shown in the middle filter membrane 4 is a disc-shaped structure with two convex sides, which is supported by the support structure in the diversion assembly 3.

[0151] At this point, press the filter assembly into the filter chamber and press the support structure at the center of the filter assembly against the flow plate in the filter chamber.

[0152] It is understandable that filter membranes that have not undergone the above processing methods cannot be combined with the flow distribution components. In this case, the filter membrane may detach, resulting in the inability to perform effective secondary filtration during subsequent use.

[0153] Meanwhile, to solve the problem of using only a single-layer filter membrane for filtration in the prior art, the present invention sets up a filter group with a double-layer filter membrane in a form that is far away from the filter box sealing cover. At the same time, to avoid the problem of filter membrane sticking and the resulting decrease in filtration effect and filtration efficiency, the present invention sets up a corresponding flow diversion component to avoid the problem of filter membrane sticking.

[0154] However, due to the diversion component, tiny air bubbles from the liquid medicine are filtered by the filter membrane and adsorbed at the inlet or outlet filter membrane, affecting the liquid output effect. This invention, by setting several inclined filter surfaces, can block these air bubbles near the bottom of the filter, effectively avoiding the problem of poor liquid output caused by trapped air.

[0155] To address the issue that in existing technologies, poor liquid flow in filters during prolonged or intermittent operation can affect the stability of the filters during operation, this application incorporates a second liquid-passing cavity at its lower part as a buffer, and utilizes the opening in the filter assembly to create a movable chamber that communicates with the first liquid-passing cavity.

[0156] During the intermittent period, some air is stored in the lower part of the second liquid-passing cavity. When the filter is restarted, the second liquid-passing cavity intercepts some air bubbles, preventing them from entering the upper part of the first liquid-passing cavity, which can effectively improve the filtration efficiency when the filter is restarted.

[0157] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0158] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A medical filter, wherein a filter cartridge is arranged in a circular disc structure comprising an input cartridge and an output cartridge, the filter cartridge is arranged longitudinally, the input cartridge is provided with a liquid inlet above, the output cartridge is provided with a liquid outlet below, and a flow splitting component and a flow plate are arranged between the input cartridge and the output cartridge; the flow splitting component is wrapped with an inlet filter membrane and an outlet filter membrane on both sides, forming a first liquid flow cavity supported by the flow splitting component, for receiving liquid filtered by the inlet filter membrane; the outlet filter membrane and the flow plate form a second liquid flow cavity, for receiving liquid filtered by the outlet filter membrane, and the second liquid flow cavity is separated by the flow splitting component and the flow plate, and is divided into an upper part and a lower part; for the outlet filter membrane, in response to filtration, the outlet filter membrane filters liquid in the first liquid flow cavity in the upper part of the second liquid flow cavity; in response to filtration stopping, the outlet filter membrane blocks gas that has not been discharged in the lower part of the second liquid flow cavity; wherein the flow plate is arranged in the output cartridge and is provided with a flow hole, and the flow hole is arranged on one side close to the liquid inlet; the flow hole is located in the upper part of the second liquid flow cavity, and the flow hole itself is not separated by the partition; the flow splitting component comprises a plurality of groups of support structures arranged in different lengths; the filter cartridge is sealed by an input cover and an output cover; at least one group of support structures is pressed against the flow plate, and any group of support structures does not contact the input cover; the long axis of each support structure is perpendicular to the corresponding plane of the flow plate; for each support structure with the same vertical distance from the liquid inlet, the length is the same; the inlet filter membrane and the outlet filter membrane are supported by the support structures, and form the first liquid flow cavity. characterized in that The input cartridge is used to receive liquid to be filtered, and the inlet filter membrane forms an inclined surface with the flow splitting component, so as to increase the filtering area; wherein the inlet filter membrane performs primary filtration on the liquid in the filtering state; during the primary filtration, the input cartridge is gradually filled with liquid and flows into the first liquid flow cavity. The inclined surface is supported by the support structures and is formed by the height difference of each support structure, and the central region of the inlet filter membrane is higher than the edge region, forming a protruding structure protruding towards the input cover. The flow holes are concentratedly distributed in the upper central region of the flow plate, and all the flow holes are located above the partition; the output cover and the flow plate form an output cartridge, and the output cartridge communicates the second liquid flow cavity and the liquid outlet. The outlet filter membrane filters the liquid filtered by the inlet filter membrane to perform secondary filtration; in the filtering state, the upper part of the second liquid flow cavity receives the filtered liquid and flows into the output cartridge through the flow hole. The inlet filter membrane and the outlet filter membrane are arranged as nuclear pore membranes. 8.A method for manufacturing a medical filter according to any one of claims 1-7, comprising: manufacturing a shell, a flow plate and a sealing cover; and forming a filter group comprising an outlet filter membrane, a flow splitting component and an inlet filter membrane; assembling the filter; characterized in that, when forming the filter group, it comprises: ​ ​ ​ ​ 2. The medical filter of claim 1, wherein, ​ ​ ​ 3. The medical filter of claim 2, wherein, ​ ​ ​ 4. The medical filter of claim 3, wherein, ​ 5. The medical filter of claim 1, wherein, ​ ​ 6. The medical filter of claim 1, wherein, ​ ​ 7. The medical filter according to any one of claims 1 to 6, characterized in that ​ ​ ​ ​ ​ ​ ​ Step S1, cutting the liquid-out filter membrane and the liquid-in filter membrane, and pressing the edges of the liquid-out filter membrane and the liquid-in filter membrane to form a filter bag; Step S2, opening the filter bag and assembling the shunt assembly into the filter bag; and Arranging the filter bag so that the opening of the filter bag is located at the preset opening; Step S3, pressing the filter group towards the overflow plate so that the edges of the filter bag are pressed against the shell, and the opening is located between the overflow plate and the shunt assembly; The preset opening is parallel to the support structure of the shunt assembly, and the opening size is not greater than 1 / 3 of the circumference of the shunt assembly.

9. The method of claim 8, wherein the filter is a medical filter. In the step S1, when cutting the liquid-out filter membrane, the liquid-out filter membrane is cut into an ellipse, the short axis of which is not less than the diameter of the overflow plate, and the long axis of which is not less than the diameter of the shell and not greater than 1.5 times the horizontal projection diameter of the shunt assembly; When cutting the liquid-in filter membrane, the liquid-in filter membrane is cut into a circle, the diameter of which is not less than the diameter of the shell and not greater than the long axis of the liquid-out filter membrane; When forming the filter bag, the liquid-in filter membrane is pressed from the corresponding side facing the liquid-out filter membrane; The preset opening is located at the corresponding position of the long axis of the liquid-out filter membrane; When assembling the filter, the filter group is formed into a disc-shaped filter group after being supported by the shunt assembly, and the filter group is pressed towards the overflow plate, and the edges of the liquid-in filter membrane are pressed into the shell of the filter to complete the assembly.

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