CN220779730U - Centrifugal filter assembly and centrifugal filter device comprising same - Google Patents

Abstract

The utility model discloses a centrifugal filter assembly and a centrifugal filter device formed by the same, wherein the centrifugal filter assembly comprises a centrifuge tube, a filter membrane and a cover plate, the centrifuge tube comprises an upper tube part and a lower filter part which are communicated, at least one side of the lower filter part is provided with an opening, the cover plate comprises a first area and an annular second area which is wrapped on the periphery of the first area, the filter membrane is fixed on the inner surface of the first area in a sealing way, a through hole is arranged in the first area, and the through hole is communicated with the downstream surface of the filter membrane and the outer surface of the cover plate; the thickness of the filter membrane is D, the height difference between the inner surface of the rib and the inner surface of the first region in the thickness direction of the filter membrane is H, and the following relation is satisfied: H-D is less than or equal to 0.5mm or H+D is less than or equal to 0.5mm. The centrifugal filter assembly can improve the success rate that the pipette tip can extend into the bottom of the inner cavity of the lower filter part by one-time insertion operation, thereby reducing the risk of puncturing the filter membrane and damaging the pipette tip and improving the working efficiency of sucking concentrated solution.

Description

Centrifugal filter assembly and centrifugal filter device comprising same

Technical Field

The utility model relates to the technical field of filtration, in particular to a centrifugal filter assembly and a centrifugal filter device formed by the same.

Background

Centrifugal filters can be used to separate biological materials such as abzymes, nucleic acids, and proteins for concentration, desalination, purification, and fractionation purposes. The centrifugal filter mainly utilizes the filter membrane fixed at the lower end of the centrifugal tube to realize the concentration of the target biological sample, and the feed liquid is divided into filtrate and concentrated solution, and the filtrate and the concentrated solution are possibly collected and utilized by users.

In the centrifugal filter provided by the prior art CN211159301U, the filter membrane is sealed by pressing the pressure plate and the sealing ring. At least one of the front side and the rear side of the lower filtering part of the centrifugal tube is provided with an opening, the peripheral side of the opening is provided with an annular sealing groove, a sealing ring is arranged in the sealing groove, the filter membrane is pressed on the sealing ring, the pressing plate is tightly attached to the downstream surface of the filter membrane, and the lower end of the pressing plate is provided with a penetrating fluid outlet, namely the filter membrane and the pressing plate are positioned on the peripheral side of the opening; in order to accommodate the concentrated solution, the lower filtering part is provided with a concentrated solution chamber, and the side wall of the formed opening is provided with a certain thickness, namely a ridge, the filter membrane is pressed on the outer surface of the ridge in a sealing way, the upper surface of the bottom ridge is higher than the lowest part of the concentrated solution chamber, and after centrifugation is finished, the pipette tip is required to be inserted into the bottom of the concentrated solution chamber to take out the concentrated solution. However, when inserted, the pipette tip often sticks to the upper surface of the bottom edge, rather than to the bottom of the concentrate chamber. Therefore, the pipette tip is required to be pulled out upwards for part of the length and then inserted downwards, and the pipette tip is inserted for a plurality of times, so that the risk of stabbing a filter membrane is improved, and the working efficiency is also reduced; and the edge and the upstream surface surrounding area of the filter membrane form a cavity which is communicated with the concentrated solution chamber and has a certain volume, concentrated solution can be contained in the cavity, after the centrifugal filtration operation is finished, the concentrated solution has higher viscosity, part of concentrated solution remains in the cavity, and the residual concentrated solution is not easy to collect, so that the yield of target macromolecules is reduced.

Therefore, it is necessary to improve the structure of the conventional centrifugal filter device, avoid the formation of a cavity, and facilitate the subsequent collection of the concentrate.

Disclosure of Invention

Aiming at the defects of the prior art, the utility model aims to provide a centrifugal filter assembly and a centrifugal filter device formed by the same, which solve the problem that a liquid gun head is easy to stab a filter membrane when the existing centrifugal filter collects concentrated liquid.

In order to achieve the above purpose, the present utility model adopts the following technical scheme:

a centrifugal filter assembly comprises a centrifuge tube, a filter membrane and a cover plate, wherein the centrifuge tube comprises an upper tube part and a lower filter part which are communicated, the upper tube part is provided with an inlet, at least one side of the lower filter part is provided with an opening,

the cover plate comprises a first area and an annular second area which is wrapped on the periphery of the first area, the filter membrane is fixed on the inner surface of the first area in a sealing way, through holes are formed in the first area, and the through holes are communicated with the downstream surface of the filter membrane and the outer surface of the cover plate;

the inner surface of the second region is in sealing connection with the outer surface of the edge of the periphery of the opening so that the cover plate is fixed on the lower filtering part;

the thickness of the filter membrane is D, the height difference between the inner surface of the edge and the inner surface of the first region in the thickness direction of the filter membrane is H, and the following relation is satisfied: H-D is less than or equal to 0.5mm or H+D is less than or equal to 0.5mm.

In the centrifugal filter assembly, the filter membrane is fixed on the inner surface of the first area of the cover plate in a sealing way, after the cover plate is fixed with the lower filter part in a sealing way through the second area, in order to ensure that the thickness of the edge at the periphery of the opening or the filter membrane on the first area is directly exposed in the inner cavity of the lower filter part is not more than 0.5mm, namely, the height difference between the inner surface of the edge and the upstream surface of the filter membrane needs to be controlled, the height difference can be controlled by ensuring that H-D is less than or equal to 0.5mm or H+D is less than or equal to 0.5mm, specifically, H-D is less than or equal to 0.5mm, the upstream surface of the filter membrane is positioned in the opening, and the difference between the height difference H between the inner surface of the edge at the periphery of the opening and the inner surface of the first area and the thickness D of the filter membrane is limited to be less than 0.5mm; the diameter of the tail end of the liquid-transferring gun head is about 1.2mm, so that after centrifugal filtration, the liquid-transferring gun head can be guided by the edge and the first area of the periphery of the opening in the process of stretching into the inner cavity of the lower filtering part to recover concentrated liquid, and is not easy to incline, even if the liquid-transferring gun head inclines, the tip of the liquid-transferring gun head cannot stay and rest on the edge of the periphery of the opening for a long time, particularly the side surface of the bottom edge, but can more easily directly enter the bottom of the inner cavity of the lower filtering part, namely the success rate of stretching the liquid-transferring gun head into the bottom of the inner cavity of the lower filtering part by one-time insertion operation is improved, thereby reducing the risk of puncturing a filter membrane and damaging the liquid-transferring gun head, and improving the working efficiency of absorbing concentrated liquid. And H+D is less than or equal to 0.5mm, even if the upstream surface of the filter membrane protrudes from the inner surface of the ridge, and the protruding height is less than 0.5mm, the size of the concentrate chamber is not adversely affected, and the gun head can be smoothly inserted into the bottom of the concentrate chamber without stabbing the filter membrane. In addition, when H-D is less than or equal to 0.5mm, the volume of the area surrounded by the edge side surface and the filter membrane is small, and almost no, namely the volume of the cavity is reduced as much as possible, so that concentrated liquid residues cannot be formed, namely concentrated liquid adhesion is basically avoided on the edge side surface at the periphery of the opening, almost all concentrated liquid is collected into a concentrated liquid chamber, the subsequent collection is convenient and quick, and the concentrated liquid and target macromolecule yield is high.

Preferably, the first region protrudes from the second region, and the first region is embedded in the opening, and the inner surface of the second region is sealed and fixed to the outer surface of the rib; the arrangement is such that the inner surface of the first region is as close as possible to the inner surface of the ridge at the periphery of the opening, thereby controlling the value of the height difference H to achieve the purpose of H-D0.5 mm or H+D 0.5mm.

Preferably, the width W1 of the gap between the side wall of the ridge and the side wall of the first region is less than or equal to 0.3mm, the width of the gap is controlled, the shape and the size of the first region are matched with the shape and the size of the opening, so that the second region positioned at the periphery of the first region corresponds to the ridge positioned at the periphery of the opening, the second region is conveniently positioned and connected with the outer surface of the ridge in a sealing way, on the other hand, the gap between the side wall of the ridge and the side wall of the first region is small enough to form a space capable of retaining concentrated solution, and almost all concentrated solution is concentrated in the inner cavity of the lower filtering part; for the ribs at the top of the opening and the top side wall of the first area, the width of the gap is controlled, so that the inner surface of the ribs and the inner surface of the first area form approximately continuous surfaces as much as possible, the situation that the pipette sticks to the top gap to slide and then the filter membrane is pricked can be avoided as much as possible, and the probability of the filter membrane being pricked is reduced.

Preferably, the width of the second region is W2, and the width of the outer surface of the rib is W3, satisfying the following relationship: 0.5W3W 2 is less than or equal to W3; when the first area is embedded into the opening, the second area covers part of the outer surface of the edge, the width of the second area and the width of the outer surface of the edge are controlled, so that the width of the second area is smaller than the width of the outer surface of the edge, on one hand, the positioning and sealing connection between the second area and the outer surface of the edge are facilitated, the connection part between the second area and the outer surface of the edge is limited in the area corresponding to the second area, further the appearance of a product is improved, and on the other hand, the width of the second area is not too small, so that the sealing connection area of the second area and the edge is too small, and the connection strength of the second area and the edge is ensured.

Preferably, the inner surface of the second region and the outer surface of the rib are sealed and fixed by ultrasonic welding or bonding.

The centrifuge tube and the cover plate are generally made of plastic materials, are sealed and fixed through ultrasonic welding or bonding, and have the advantages of high connection speed, high strength, good tightness, low cost and no damage to workpieces. And because the ratio setting of the width of second district and the surface width of arris, no matter be the molten feed liquid that produces in the ultrasonic welding process, the binder that bonds the use, all be difficult for flowing to the lateral wall of arris, but evenly lay at the arris towards the surface of cover plate, the appearance of the centrifugal filtration subassembly of final formation is comparatively clean and tidy pleasing to the eye.

Preferably, the roughness Ra of the outer surface of the rib is 0.8-3.2. The surface roughness of the parameters enables the sealing connection performance between the second area and the outer surface of the edge to be more reliable, and molten material liquid or adhesive cannot flow outwards at will, which is beneficial to the appearance attractiveness of the centrifugal filter assembly.

Preferably, the inner surface of the first region comprises an annular welding region and a diversion region positioned inside the welding region, and the welding region is close to the edge; the periphery of the filter membrane is welded and sealed to the welding area, and the filter membrane covers the diversion area.

The welding area is positioned in the area, close to the outer edge, of the inner surface of the first area, and correspondingly, the size of the filter membrane is close to or equal to that of the inner surface of the first area, so that the outer edge of the filter membrane is correspondingly welded with the welding area; compared with a pressed film, the filter film adopts a welding and fixing mode, the sealing performance is more reliable, and a sealing ring and a jacket are omitted, so that the structure of the centrifugal filter assembly is simplified, the assembly steps are reduced, and the cost is reduced; and the filter membrane covers the flow guiding area, the filtrate formed by the filter membrane can rapidly flow out of the lower filtering part through the flow guiding area, and the upstream and downstream of the filter membrane are effectively separated, and the filtrate and the concentrated solution are separated.

Preferably, a plurality of diversion trenches are formed in the diversion area, each through hole is correspondingly arranged at the tail end of each diversion trench, and the adjacent through holes are at least partially staggered.

The diversion trench is used for guiding the filtrate to the through hole and then flows out of the lower filtering part through the through hole; it should be noted that the outer edges of the diversion trench and the diversion area are arranged at intervals, namely, the boundary line between the diversion area and the welding area is properly kept away, so that the filter membrane is prevented from being pressed on the trench wall of the diversion trench by the welding head in the welding process, and the filter membrane is further prevented from being broken; the through holes are at least partially staggered, so that the diameter of the through holes is larger and can be slightly larger than the width of the diversion trench, and workpieces for processing adjacent through holes can be prevented from interfering with each other, the processing of the through holes is facilitated, and the diameter of the through holes can be increased to a certain extent.

Preferably, a guiding surface is arranged at the bottom of the upper pipe part, is positioned at the same side as the opening, and extends obliquely relative to the central line of the upper pipe part; the inclination angle of the guide surface relative to the horizontal direction is 12-18 degrees.

The guiding surface has the function of guiding the stock solution entering the upper pipe part downwards along the guiding surface, and after reaching the bottom of the guiding surface, the stock solution steadily flows to the inner surface of the edge, at the moment, the distance difference between the upstream surface of the filter membrane and the inner surface of the edge is very small, so that the stock solution flowing to the upstream surface of the filter membrane is more gentle and stable, and the larger impact effect on the filter membrane can not be formed.

Preferably, the top end of the upper pipe part is provided with an integrally formed annular flange, and the outer edge of the flange is provided with at least one balance groove which is used for communicating the upstream space and the downstream space of the filter membrane; or alternatively

The flange is a plurality of block structures which are arranged at the top end of the upper pipe part in a dispersing mode, and the balance groove is formed by gaps between adjacent block structures.

The balancing tank has the effects of communicating the upstream and the downstream of the filter membrane and balancing the pressure difference between the upstream and the downstream so as to accelerate the centrifugal filtration rate, and meanwhile, the flange is also used for positioning the centrifugal filter assembly in the receiving container, so that the stability of the centrifugal filter assembly is ensured, and the phenomenon that the centrifugal filter assembly moves relative to the receiving container to cause abrasion in the centrifugal filter process is avoided.

In order to achieve the above purpose, the present utility model further adopts the following technical scheme:

the centrifugal filter device comprises a receiving container, a cover and the centrifugal filter assembly, wherein the centrifugal filter assembly stretches into the receiving container, and the top end of the upper pipe part is pressed and held on a pipe orifice of the receiving container; the cap is fitted to the mouth of the receiving container and the top end of the upper tube portion to fix the centrifugal filter assembly with respect to the receiving container.

According to the centrifugal filter device, the centrifugal filter assembly can be stably fixed in the receiving container, the centrifugal filter assembly does not move relative to the receiving container, the risk of damaging the centrifugal filter assembly can be reduced, the probability of the filter membrane being punctured by the liquid-moving gun head is reduced through the cooperation of the cover plate, the filter membrane and the ribs, filtrate reaches the downstream side of the filter membrane and flows downwards along the inner surface of the first area during centrifugal filtration, finally, the filtrate is discharged through the through hole and enters the receiving container, and concentrated solution remains in the inner cavity of the lower filter part to be sucked by the liquid-moving gun head.

In summary, compared with the prior art, the utility model has at least the following beneficial effects:

the centrifugal filter assembly can improve the success rate of inserting the liquid-transferring gun head into the bottom of the inner cavity of the lower filter part at one time, thereby reducing the risk of puncturing the filter membrane and damaging the liquid-transferring gun head, improving the working efficiency of absorbing concentrated liquid, reducing the volume of the cavity as much as possible, and ensuring that concentrated liquid residues cannot be formed, namely, the side surface of the edge of the periphery of the opening basically does not have concentrated liquid adhesion, almost all concentrated liquid is collected into the concentrated liquid chamber, the subsequent collection is convenient and quick, and the concentrated liquid and target macromolecule yield is high.

According to the centrifugal filter, the centrifugal filter assembly in the centrifugal filter can be stably fixed with the receiving container, so that shaking in the centrifugal filter process is reduced, and the centrifugal efficiency is more stable and higher.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present utility model, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic view of a centrifugal filter assembly according to an embodiment of the utility model.

Fig. 2 is a schematic axial cross-sectional view of the centrifugal filter assembly of fig. 1.

Fig. 3 is a schematic cross-sectional view of a lower filter portion of the centrifugal filter assembly of fig. 1.

Fig. 4 is an enlarged view at a in fig. 3.

FIG. 5 is a schematic view showing the positions of the first region, the filter membrane and the ribs according to another embodiment of the present utility model.

FIG. 6 is a schematic view showing the positions of the first region, the filter membrane and the ribs according to another embodiment of the present utility model.

Fig. 7 is a schematic view of a partial cross-section of a centrifugal filter assembly according to an embodiment of the utility model.

Fig. 8 is a schematic view of a pipette tip within a lower filter section.

Fig. 9 is an enlarged view at B in fig. 8.

Fig. 10 is a schematic structural view of a cover sheet according to an embodiment of the present utility model.

Fig. 11 is a front view of the flap of fig. 10.

Fig. 12 is a cross-sectional view at B in fig. 11.

FIG. 13 is a schematic view of the structure of a centrifuge tube according to an embodiment of the present utility model.

Fig. 14 is an isometric cross-sectional schematic view of the centrifuge tube of fig. 13.

Fig. 15 is an enlarged view at C in fig. 14.

Fig. 16 is a schematic view of a centrifugal filter according to an embodiment of the utility model.

Fig. 17 is a schematic axial cross-sectional view of the centrifugal filter of fig. 16.

Description of the reference numerals

1. Centrifuging tube; 11. an upper pipe section; 111. a guide surface; 112. a flange; 113. a balancing groove; 12. a lower filtering part; 121. an opening; 122. a rib; 1221. a top edge; 1222. side edges; 1223. a bottom edge; 123. a concentrate chamber;

2. a filter membrane;

3. a cover plate; 31. a first zone; 311. a welding area; 312. a diversion area; 313. a diversion trench; 32. a second zone; 321. welding the protrusions; 33. a through hole;

4. pipetting gun heads;

5. a receiving container;

6. and a cover.

Detailed Description

The following description of the embodiments of the present utility model will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the utility model are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

As shown in fig. 1 to 9, the present utility model provides a centrifugal filter assembly, specifically, the centrifugal filter assembly of the present embodiment includes a centrifuge tube 1, a filter membrane 2 and a cover plate 3, the centrifuge tube 1 is used for containing a stock solution to be centrifugally filtered, the filter membrane 2 is used for filtering the stock solution to form a filtrate and a concentrate, the filter membrane 2 is sealed and fixed on the cover plate 3, and then the cover plate 3 is sealed and fixed on the centrifuge tube 1, so that the filter membrane 2 is sealed and fixed on the centrifuge tube 1, and separates an inner space and an outer space of the centrifuge tube 1, and separates the filtrate and the concentrate. As shown in fig. 2, the centrifuge tube 1 comprises an upper tube part 11 and a lower filter part 12 which are communicated, wherein the upper tube part 11 is provided with an inlet for the raw liquid to enter, at least one side of the lower filter part 12 is provided with openings 121, the number of the openings 121 corresponds to the number of the filter membranes 2 and the cover plates 3, if only one opening 121 exists, the number of the filter membranes 2 is a group, one or more filter membranes exist in the group, and the number of the cover plates 3 is also one; if the number of the openings 121 is two and the openings are symmetrically arranged in the lower filtering part 12, the number of the filtering membranes 2 is two, one or more filtering membranes are arranged in one group, the number of the cover plates 3 is also two, and as shown in fig. 2, the lower filtering part is also provided with a concentrated solution chamber 123 communicated with the openings 121.

As shown in fig. 10 and 11, the cover plate 3 comprises a first region 31 and an annular second region 32 surrounding the periphery of the first region 31, the filter membrane 2 is fixed on the inner surface of the first region 31 in a sealing way, through holes 33 are arranged in the first region 31, and the through holes 33 are communicated with the downstream surface of the filter membrane 2 and the outer surface of the cover plate 3; the inner surface of the second region 32 is sealingly connected to the outer surface of the ribs 122 of the outer periphery of the opening 121 so that the cover sheet 3 is fixed to the lower filter portion 12; wherein the thickness of the filter membrane 2 is D, and the height difference between the inner surface of the rib 122 and the inner surface of the first region 31 in the thickness direction of the filter membrane 2 is H, satisfying the following relationship: H-D is less than or equal to 0.5mm or H+D is less than or equal to 0.5mm. I.e. the filter membrane 2 sealingly fastened to the inner surface of the first zone 31, which inner surface may be higher than the inner surface of the rib 122 by a height not more than 0.5mm, or the filter membrane 2 sealingly fastened to the inner surface of the first zone 31 may be lower than the inner surface of the rib 122 by a height not more than 0.5mm.

Specifically, in the embodiment shown in fig. 3 and fig. 4, the inner surface of the ridge 122 is higher than the inner surface of the first region 31, the upstream surface of the filter membrane 2 is higher than the inner surface of the ridge 122, the height difference H between the inner surface of the ridge 122 and the inner surface of the first region 31 in the thickness direction of the filter membrane 2 is the height of the inner surface of the ridge 122 higher than the inner surface of the first region 31, the thickness of the filter membrane 2 is D, h+d is less than or equal to 0.5mm, and D is greater than or equal to H, so that the exceeding thickness of the inner surface of the filter membrane 2 higher than the inner surface of the ridge 122 is much smaller than 0.5mm, the influence on the width of the concentrate chamber 123 is very small, and the smooth and rapid insertion of the pipette tip 4 into the bottom of the concentrate chamber 123 is ensured, thereby reducing the risk of puncturing the filter membrane 2 and damaging the pipette tip 4, and improving the working efficiency of sucking the concentrate.

Alternatively, in another embodiment shown in fig. 5, the inner surface of the first region 31 is higher than the inner surface of the rib 122, so that the height difference H between the inner surface of the rib 122 and the inner surface of the first region 31 in the thickness direction of the filter membrane 2 is the height of the inner surface of the first region 31 higher than the inner surface of the rib 122, and meanwhile, the thickness of the filter membrane 2 is D, h+d is less than or equal to 0.5mm, that is, the thickness of the first region 31 and the filter membrane 2 directly exposed to the concentrate chamber 123 is not more than 0.5mm, the influence on the width of the concentrate chamber 123 is relatively small, so that the pipette tip 4 can be quickly and smoothly inserted into the concentrate chamber 123.

In another embodiment shown in fig. 6, the filter membrane 2 is sealed and fixed on the inner surface of the first region 31, the upstream surface is lower than the inner surface of the rib 122, the height difference H between the inner surface of the rib 122 and the inner surface of the first region 31 in the thickness direction of the filter membrane 2 is the height of the inner surface of the rib 122 higher than the inner surface of the first region 31, the thickness of the filter membrane 2 is D, H-D is less than or equal to 0.5mm, the thickness of the rib 122 at the outer periphery of the opening 121 directly exposed in the inner cavity of the lower filtering part 12 is not greater than 0.5mm, and when the concentrated solution is recovered, the end of the pipette tip 4 with the diameter of about 1.2mm is not clamped on the rib 122 at the outer periphery of the opening 121 for a long time, but is directly inserted into the concentrated solution chamber 123, so that the functions of reducing the risk of tearing the filter membrane 2 and damaging the pipette tip 4 and improving the working efficiency of sucking the concentrated solution can be achieved, as shown in fig. 8 and 9. On the other hand, when H-D is less than or equal to 0.5mm, the volume of the area surrounded by the edge 122 and the filter membrane 2 is small, and almost no, i.e. the volume of the cavity is reduced as much as possible, so that concentrate residues cannot be formed, i.e. the edge 122 at the periphery of the opening 121 is basically free from concentrate adhesion, almost all concentrate is collected into the concentrate chamber 123, subsequent collection is convenient and rapid, and the yield of concentrate and target macromolecules is high.

In general, in the present application, the thickness of the filter membrane 2 is D, the height difference between the inner surface of the ridge 122 and the inner surface of the first region 31 in the thickness direction of the filter membrane 2 is H, so that H-D is less than or equal to 0.5mm or h+d is less than or equal to 0.5mm, and the pipette tip can be quickly inserted into the bottom of the concentrate chamber 123 at one time, so that the filter membrane 2 is not damaged in the process of inserting the pipette tip.

It should be noted that the outer edge of the filter membrane 2 needs to be sealed and fixed to the outer edge of the inner surface of the first region 31, and the fixing manner may be welding, fusing or bonding, which has a certain effect on the thickness D of the filter membrane 2, and the thickness of the filter membrane 2 may be determined by measuring the central portion or other unconnected portion of the filter membrane 2.

As shown in fig. 2 and 12, the first region 31 protrudes from the second region 32, and the first region 31 is inserted into the opening 121, and the inner surface of the second region 32 is sealed and fixed to the outer surface of the rib 122.

Taking the cover plate 3 as a square or trapezoid as an example, the shape of the first region 31 is basically the same as that of the cover plate 3, the shape of the annular second region 32 corresponds to that of the outer edge of the cover plate 3, and the cover plate is in a square annular shape as shown in fig. 11; if the cover sheet 3 is circular, the first region 31 may be circular or square, and the corresponding second region 32 may be circular or annular inside the outer circle.

Meanwhile, the shape of the first region 31 also corresponds to the shape of the opening 121, so that the first region 31 can be inserted into the opening 121, that is, if the opening 121 is square, the first region 31 is also square, the opening 121 is circular, and the first region 31 is also circular, thereby facilitating the insertion of the first region 31 into the opening 121, and the inner surface of the first region 31 is as close to the inner surface of the rib 122 at the periphery of the opening 121 as possible, so as to control the value of the height difference H, and on the other hand, the second region 32 can be sealed corresponding to the outer surface of the rib 122.

Specifically, as shown in fig. 4, a gap width W1 between the side wall of the rib 122 and the side wall of the first region 31 is less than or equal to 0.3mm, and the gap width is controlled so that, on one hand, the second region 32 located at the periphery of the first region 31 corresponds to the rib 122 located at the periphery of the opening 121, so that the second region 32 is positioned and connected with the outer surface of the rib 122 in a sealing manner, and on the other hand, the gap between the side wall of the rib 122 and the side wall of the first region 31 is small enough to form a space capable of forming a concentrated solution, so that almost all the concentrated solution is concentrated in the concentrated solution chamber 123 of the lower filtering portion 12; as shown in fig. 2, the width of the gap between the ridge 122 at the top of the opening 121 and the top side wall of the first region 31 is controlled, so that the inner surface of the ridge 122 and the upstream surface of the filter membrane 2 are formed as nearly continuous as possible, the situation that the pipette sticks to the top gap to slide and then to puncture the filter membrane 2 is avoided as much as possible, and the probability of puncture of the filter membrane 2 is reduced.

As shown in fig. 2, the second region 32 has a width W2, and the ribs 122 have an outer surface having a width W3, satisfying the following relationship: 0.5W3W 2 is less than or equal to W3; when the first region 31 is embedded into the opening 121, the second region 32 covers part of the outer surface of the rib 122, the width of the second region 32 and the width of the outer surface of the rib 122 are controlled, so that the width of the second region 32 is smaller than the width of the outer surface of the rib 122, on one hand, the positioning and sealing connection between the second region 32 and the outer surface of the rib 122 are facilitated, the connection part between the second region 32 and the outer surface of the rib 122 is limited to the area corresponding to the second region 32 on the outer surface of the rib 122, and the appearance of the product is improved, on the other hand, the width of the second region 32 is not too small, so that the sealing connection area between the second region 32 and the rib 122 is too small, and the connection strength between the second region 32 and the rib 122 is ensured.

As shown in fig. 11, the peripheral edge 122 of the opening 121 includes a top edge 1221 and a bottom edge 1223 disposed opposite to each other and two side edges 1222 disposed opposite to each other, and the widths of the top edge 1221, the bottom edge 1223, and the two side edges 1222 are denoted as W3, but specific values of each W3 may be different, where the width of the top edge 1221 refers to the width of all areas below the guide surface 111, including the width corresponding to the transitional cambered surface, as shown in fig. 2, and the dotted line indicates the bottom of the guide surface 111. The width W2 of each edge of the second region 32 is not necessarily the same, and it is only necessary to ensure that the ratio between the width of each edge of the second region 32 and the width of the corresponding edge 122 satisfies the above relationship, that is, the width of the side edge 1222 corresponds to the width of the edge on both sides of the second region 32, the width of the top edge 1221 corresponds to the width of the edge on the top of the second region 32, and the width of the bottom edge 1223 corresponds to the width of the edge on the bottom of the second region 32, which satisfies 0.5W3 +.w2 < W3. The angle R1 between the two side edges 1222 relative to the axial direction is 2-6, and correspondingly, the angle between the edges on both sides of the second region 32 is 2-6.

Preferably, the inner surface of the second region 32 is sealed to the outer surface of the rib 122 by ultrasonic welding or bonding.

The centrifuge tube 1 and the cover plate 3 are generally made of plastic materials, are sealed and fixed through ultrasonic welding or bonding, and have the advantages of high connection speed, high strength, good tightness, low cost and no damage to workpieces. And because the ratio of the width of the second region 32 to the width of the outer surface of the edge 122 is set, the molten liquid generated in the ultrasonic welding process and the adhesive used for bonding are not easy to flow to the side wall of the edge 122, but are uniformly paved on the surface of the edge 122 facing the cover plate 3, and the appearance of the finally formed centrifugal filter assembly is tidy and attractive. In the preferred embodiment, the inner surface of the second region 32 is welded to the outer surface of the rib 122 by ultrasonic welding, and as shown in fig. 11 and 12, the inner surface of the second region 32 has a welding protrusion 321 for melting to form molten liquid material during ultrasonic welding, and is welded to the outer surface of the rib 122.

Preferably, the external surface of the rib 122 has a roughness Ra of 0.8 to 3.2, preferably a value of 1.6, at which the surface roughness of the aforementioned parameters, whether ultrasonic welding or bonding, allows a more reliable sealing connection between the second region 32 and the external surface of the rib 122, without the molten liquid or adhesive flowing out at will, which is advantageous for the aesthetic appearance of the centrifugal filter assembly.

As shown in fig. 10 and 11, the inner surface of the first region 31 includes an annular welding region 311 and a flow guiding region 312 located inside the welding region 311, the welding region 311 being adjacent to the rib 122; the outer periphery of the filter membrane 2 is welded and sealed to the weld zone 311, and the filter membrane 2 covers the flow guiding zone 312.

The shape of the filter membrane 2 is identical to the shape of the inner surface of the first region 31, and the size of the filter membrane 2 is close to or equal to the size of the inner surface of the first region 31, and the shapes and the areas of the two are identical, for example, when the filter membrane 2 and the inner surface of the first region 31 are square, the length and the width of the filter membrane 2 are basically identical to those of the inner surface of the first region 31, if the filter membrane 2 and the inner surface of the first region 31 are round, the diameter of the filter membrane 2 is basically identical to that of the inner surface of the first region 31, therefore, when the filter membrane 2 covers the inner surface of the first region 31, the outer edge of the filter membrane 2 is close to the outer edge of the first region 31 and is opposite to the welding region 311 positioned on the outer edge of the inner surface of the first region 31, the outer edge region of the filter membrane 2 is correspondingly welded with the welding region 311 positioned on the inner surface of the first region 31, the width of the region where the welding is actually formed on the filter membrane 2 is 0.5-0.75mm, and the width of the welding region 311 is also 0.5-0.75mm. Compared with the pressed film, the filter film 2 adopts a welding and fixing mode, the sealing performance is more reliable, and the sealing ring and the jacket are omitted, so that the structure of the centrifugal filter assembly is simplified, the assembly steps are reduced, and the cost is reduced.

A plurality of diversion trenches 313 are formed in the diversion area 312, the diversion trenches 313 are vertically arranged at intervals, meanwhile, the diversion trenches 313 at the outermost side are arranged at intervals with the outer edge of the diversion area 312, namely, the boundary line between the diversion area 312 and the welding area 311 is properly kept away, the distance between the outer side of the diversion trench 313 at the outermost side and the outer edge of the inner surface of the first area 31 is more than 0.75mm, preferably more than 1mm, and the filter membrane 2 is prevented from being pressed on the groove wall of the diversion trench 313 by a welding head in the welding process, so that the filter membrane 2 is fractured.

Each through hole 33 is correspondingly arranged at the tail end of each diversion trench 313, and the diversion trenches 313 are used for guiding filtrate to the through holes 33 and then flow out of the lower filtering part 12 through the through holes 33; and the adjacent through holes 33 are at least partially dislocated, as shown in fig. 11, for convenience in processing, the through holes 33 are divided into two groups in the vertical direction, each group is in the same horizontal line, one group is relatively upper, and the other group is relatively lower, so that the adjacent through holes 33 are partially dislocated, thereby, the diameter of the through holes 33 can be larger, the width of the through holes can be slightly larger than the width of the diversion trench 313, and the workpieces for processing the adjacent through holes 33 can be prevented from interfering with each other, thereby facilitating the processing of the through holes 33.

As shown in fig. 14, the bottom of the upper pipe 11 is provided with a guiding surface 111, the guiding surface 111 and the opening 121 are located on the same side, when only one opening 121 is provided, the guiding surface 111 is also one and located on the same side as the opening 121, and when the openings 121 are two and symmetrical, the guiding surfaces 111 are also two and symmetrical to each other; and extends obliquely with respect to the center line of the upper pipe portion 11; the guide surface 111 has the function of guiding the raw liquid entering the upper tube portion 11 downward along the guide surface 111, and after reaching the bottom of the guide surface 111, the raw liquid smoothly flows to the inner surface of the ridge 122, and at this time, the difference in distance between the upstream surface of the filter membrane 2 and the inner surface of the ridge 122 is small, so that the raw liquid flowing to the upstream surface of the filter membrane 2 is relatively gentle and stable, and does not exert a large impact on the filter membrane 2. The inclination angle R2 of the guide surface 111 with respect to the horizontal direction is 12 ° to 18 °, and the inclination angle R2 enables the guide surface 111 to smoothly guide the dope to the upstream surface of the filter membrane 2. And the bottom of the guide surface 111 is connected to the top edge 1221 by a rounded transition.

As shown in fig. 13, 14 and 15, in this embodiment, the top end of the upper tube 11 has an integrally formed annular flange 112, and at least one balancing groove 113 is provided at the outer edge of the flange 112, and the balancing groove 113 is used to communicate the upstream and downstream spaces of the filter membrane 2. The top surface at any place of the flange 112 is recessed downward, the side surface at the corresponding position is recessed inward, and the bottom surface at the corresponding position is recessed upward, whereby the communicating recessed areas form the balance groove 113 of the present embodiment, as shown in fig. 15. The balancing groove 113 has the function of communicating the upstream and downstream of the filter membrane 2 and balancing the pressure difference between the upstream and downstream so as to accelerate the centrifugal filtration rate, and the flange 112 is also used for positioning the centrifugal filter assembly in the receiving container 5, so as to ensure the stability of the centrifugal filter assembly and avoid the movement of the centrifugal filter assembly relative to the receiving container 5 and abrasion during the centrifugal filtration process. Preferably, the width of the balance groove 113 is 0.3-0.6mm, the depth is 0.2-0.4mm, and the depth of the balance groove 113 is the depth of the recess.

Of course, in other embodiments, the flange 112 may be a plurality of block structures disposed at the top end of the upper tube portion 11, and the balance groove 113 is formed by the gaps between the adjacent block structures, and the flange 112 and the balance groove 113 still play the same role.

As shown in fig. 16 and 17, the present utility model further provides a centrifugal filter device, which comprises a receiving container 5 and a cover 6, and further comprises the centrifugal filter assembly of the above embodiment, wherein the centrifugal filter assembly extends into the receiving container 5, and the top end of the upper pipe portion 11 is pressed and held on the pipe orifice of the receiving container 5; the cap 6 is fitted to the mouth of the receiving container 5 and the top end of the upper tube portion 11 to fix the centrifugal filter assembly with respect to the receiving container 5.

Specifically, the centrifugal filter assembly stretches into the receiving container 5, the flange 112 at the top end of the upper pipe portion 11 is pressed at the pipe orifice of the receiving container 5, and the cover 6 is assembled at the pipe orifice of the receiving container 5 and the end and the side wall of the flange 112, so that the centrifugal filter assembly is fixed relative to the receiving container 5, and abrasion caused by movement of the centrifugal filter assembly relative to the receiving container 5 in the centrifugal filter process is avoided. The balance groove 113 on the flange 112 at the top end of the upper tube part 11 communicates with the upstream and downstream sides of the filter membrane 2, which means that the inside of the centrifuge tube 1 and the cavity between the outer wall of the centrifuge tube 1 and the inner wall of the receiving container 5 are communicated. During centrifugal filtration, the filtrate reaches the downstream side of the filter membrane 2, flows downward along the diversion trench 313, and finally is discharged through the through-hole 33 into the receiving container 5, and the concentrate remains in the concentrate chamber 123 at the bottom of the centrifugal filtration module.

The above embodiments are only preferred embodiments of the present utility model, and the scope of the present utility model is not limited thereto, but any insubstantial changes and substitutions made by those skilled in the art on the basis of the present utility model are intended to be within the scope of the present utility model as claimed.

Claims (10)

1. A centrifugal filter assembly comprises a centrifuge tube, a filter membrane and a cover plate, wherein the centrifuge tube comprises an upper tube part and a lower filter part which are communicated, the upper tube part is provided with an inlet, at least one side of the lower filter part is provided with an opening, and the centrifugal filter assembly is characterized in that,

the cover plate comprises a first area and an annular second area which is wrapped on the periphery of the first area, the filter membrane is fixed on the inner surface of the first area in a sealing way, through holes are formed in the first area, and the through holes are communicated with the downstream surface of the filter membrane and the outer surface of the cover plate;

the inner surface of the second region is in sealing connection with the outer surface of the edge of the periphery of the opening so that the cover plate is fixed on the lower filtering part;

the thickness of the filter membrane is D, the height difference between the inner surface of the edge and the inner surface of the first region in the thickness direction of the filter membrane is H, and the following relation is satisfied: H-D is less than or equal to 0.5mm; or H+D is less than or equal to 0.5mm.

2. The centrifugal filter assembly of claim 1, wherein the first region protrudes from the second region and the first region is embedded in the opening.

3. A centrifugal filter assembly according to claim 1 or 2, wherein the gap width W1 between the side walls of the ribs and the side walls of the first zone is 0.3mm or less, and/or

The width of the second region is W2, the width of the outer surface of the edge is W3, and the following relation is satisfied: 0.5W3W 2 is less than or equal to W3.

4. A centrifugal filter assembly according to claim 3, wherein the inner surface of the second zone and the outer surface of the rib are sealed and secured by ultrasonic welding or bonding.

5. The centrifugal filter assembly of claim 4, wherein the outer surface of the ribs has a roughness Ra of 0.8-3.2.

6. A centrifugal filter assembly according to claim 1 or 2, wherein the inner surface of the first zone comprises an annular weld zone and a deflector zone located inside the weld zone, the weld zone being adjacent to the rib; the periphery of the filter membrane is welded and sealed to the welding area, and the filter membrane covers the diversion area.

7. The centrifugal filter assembly of claim 6, wherein a plurality of flow guide grooves are formed in the flow guide area, each through hole is correspondingly arranged at the tail end of each flow guide groove, and adjacent through holes are at least partially staggered.

8. A centrifugal filter assembly according to claim 1 or 2, wherein the bottom of the upper tube portion is provided with a guide surface which is on the same side as the opening and extends obliquely with respect to the centre line of the upper tube portion; the inclination angle of the guide surface relative to the horizontal direction is 12-18 degrees.

9. A centrifugal filter assembly according to claim 1 or 2, wherein the top end of the upper tube portion has an integrally formed annular flange, and at least one balancing groove is provided at the outer edge of the flange, the balancing groove being for communicating the upstream and downstream spaces of the filter membrane; or alternatively

The flange is a plurality of block structures which are arranged at the top end of the upper pipe part in a dispersing mode, and the balance groove is formed by gaps between adjacent block structures.

10. A centrifugal filter device comprising a receiving container and a cover, and further comprising a centrifugal filter assembly according to any one of claims 1-9, said centrifugal filter assembly extending into the receiving container, the top end of said upper tube portion being held against the mouth of said receiving container; the cap is fitted to the mouth of the receiving container and the top end of the upper tube portion to fix the centrifugal filter assembly with respect to the receiving container.