CN211159301U

CN211159301U - Centrifugal filter

Info

Publication number: CN211159301U
Application number: CN201921769706.9U
Authority: CN
Inventors: 贾建东; 陈玉道; 柯文静
Original assignee: Hangzhou Cobetter Filtration Equipment Co Ltd
Current assignee: Hangzhou Cobetter Filtration Equipment Co Ltd
Priority date: 2019-10-21
Filing date: 2019-10-21
Publication date: 2020-08-04
Anticipated expiration: 2029-10-21

Abstract

The utility model relates to a centrifugal filter, including the centrifuging tube, a pressing plate, filter membrane and clamp cover, the centrifuging tube includes upper tube portion and lower filter part, upper tube portion and lower filter part an organic whole are formed and are constituted fluid intercommunication, the top of upper tube portion has the entry, lower filter part preceding, at least one in the back both sides is equipped with the opening, be equipped with the seal groove around the open-ended, be equipped with the sealing washer in the seal groove, the filter membrane is pressed and is held on the seal ring, the clamp plate is hugged closely in the low reaches surface of filter membrane, clamp cover has hollow inside, lower filter part and clamp plate are inserted together and are pressed from both sides the hollow inside of cover, the internal face that presss from both sides the cover closely laminates with the. The centrifugal filter realizes sealing by the extrusion effect of the jacket on the pressing plate, the filter membrane and the sealing ring, can realize the fixed sealing of the filter membrane without additional hot melting or adhesive bonding, can avoid damaging the filter membrane, and prevents leakage and adhesive dissolution.

Description

Centrifugal filter

Technical Field

The utility model relates to a filter technical field, especially a centrifugal filter.

Background

Centrifugal filters are commonly used for processing biological samples such as antigens, antibodies, enzymes, nucleic acids, proteins, etc. for concentration, desalting and purification purposes. For example, when the concentration of the protein molecules to be analyzed is too low to perform the analysis operation, the concentration may be increased by concentrating the protein molecules with a centrifugal filter, and then the analysis operation may be performed.

The centrifugal filter mainly utilizes a filter membrane fixed at the lower end of a centrifugal tube to realize the concentration of a target biological sample. In the centrifugal filtration process, the solvent penetrates through the filter membrane, and other particle pollutants in the solvent are trapped on the surface of the filter membrane or in the inner pores of the filter membrane, so that the aims of concentrating and purifying the target biological sample are fulfilled at the same time.

Each of the centrifugal filters disclosed in chinese patents CN103861460B and CN205253154U, both of which include a centrifuge tube and a filtrate receiver, the centrifuge tube includes an upper portion for sample receiving and storing, a lower portion for filtering, a filter membrane and a press plate for fixing the filter membrane, the lower portion has a retentate chamber inside, both of the centrifugal filters have filter membranes fixed to the inner surface of the press plate, and then the press plate is fixed to the outer side of the retentate chamber; specifically, if the filter membrane is firstly subjected to hot melting, then the filter membrane is welded and fixed to the inner surface of the pressing plate, and finally the pressing plate is subjected to hot melting and welded to the outer side of the retentate chamber to form a complete centrifuge tube; or, the filter membrane is adhered to the inner surface of the pressing plate by adopting an adhesive, and then the pressing plate is welded or adhered to the outer side of the retentate chamber to form a complete centrifuge tube; after the centrifugal tube is inserted into the filtrate receiver, the biological sample to be processed is injected into the centrifugal tube, an inlet at the upper end of the centrifugal tube is sealed, the centrifugal device is placed into the centrifugal tube for centrifugal filtration, the solvent penetrates through the filter membrane and is discharged into the filtrate receiver through a filtrate discharge port of the pressing plate, and other particle pollutants in the solvent are intercepted on the surface of the filter membrane or in pores inside the filter membrane, so that the biological sample is concentrated and purified.

However, when the filter membrane is heated and melted, the filter membrane is easily damaged, and the hot melting part of the filter membrane is often cracked, so that leakage is caused; however, the use of adhesives to bond the filter membranes is likely to cause the solvent dissolution problem, so that there is a need to improve the fixing manner of the filter membranes, avoid damage to the filter membranes and solve the dissolution problem, and provide stable filtration effect.

SUMMERY OF THE UTILITY MODEL

The utility model aims to achieve the purpose of improving the fixed mode of filter membrane, avoiding damaging the filter membrane, preventing the leakage, solving the problem of solvent dissolution and providing a new centrifugal filter.

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

a centrifugal filter comprises a centrifugal tube, a pressing plate and a filter membrane, wherein the centrifugal tube comprises an upper tube part and a lower filter part, the upper tube part and the lower filter part are integrally formed and form fluid communication, the top end of the upper tube part is provided with an inlet, the lower filter part comprises two side walls extending downwards from the bottom end of the upper tube part and a bottom wall connected with the two side walls, at least one of the front side and the rear side of the lower filter part is provided with an opening, the centrifugal filter is also provided with a jacket, the jacket is provided with hollow inside, an annular sealing groove is arranged around the opening, 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, the lower end of the pressing plate is provided with a penetrating fluid outlet, the lower filter part and the pressing plate are inserted into the hollow inside of the jacket together, the inner wall surface of the jacket is tightly attached to the outer surfaces of the pressing plate and the lower filtering part.

In the existing centrifugal filter, generally, the filter membrane is fixed by welding or bonding with an adhesive, specifically, for example, the filter membrane is firstly hot-melted, then welded and fixed to the inner surface of the pressure plate, and finally the pressure plate is hot-melted and welded to the outer side of the lower filtering part of the centrifugal tube; alternatively, the filter membrane is adhered to the inner surface of the pressure plate using an adhesive, and the pressure plate is welded or adhered to the outer side of the lower filter portion. However, the filter membrane is easily damaged when being heated and melted, and the hot melting part of the filter membrane is often cracked, so that leakage is caused; the use of adhesive bonding is also prone to the problem of adhesive dissolution.

The utility model provides a centrifugal filter realizes sealedly through pressing from both sides the extrusion of cover to clamp plate, filter membrane and sealing washer, does not need extra hot melt or adhesive bonding just can realize the fixed seal of filter membrane, not only can avoid haring the filter membrane, prevents to leak and the emergence that the adhesive dissolves out, has still simplified centrifugal filter's manufacturing process, reduces the production cost. In addition, the filter membrane can be replaced, and other parts can be reused.

Further, the width of the pressing plate is smaller than the distance between the outer edges of the two side walls.

The width of clamp plate is less than the distance of the outward flange of two lateral walls, consequently, the both edges of clamp plate can not support and lean on the inner wall that presss from both sides the cover, when inserting or extracting lower filter portion and clamp plate, the clamp plate can not slide along with pressing from both sides the cover, and relative slip can not take place for clamp plate and filter membrane, can avoid causing the friction damage because of the relative slip between clamp plate and filter membrane to the surface of filter membrane, protection filter membrane.

Furthermore, the outer edges of the two sides of the sealing groove are respectively provided with a bulge, the height of the bulge protruding out of the sealing ring is larger than the thickness of the filter membrane, and the two edges of the pressing plate are in contact with and abut against the inner edges of the two bulges.

The outer edges of the two sides of the sealing groove are respectively provided with a bulge, the bulges protrude out of the thickness of the sealing ring and are larger than the thickness of the filter membrane, the pressing plate can be quickly positioned along the edges of the inner sides of the two bulges during installation, and after the installation is completed, the two edges of the pressing plate are contacted and abutted against the inner side edges of the two bulges, so that the horizontal sliding of the pressing plate can be avoided. In addition, insert the in-process that presss from both sides the cover inside with lower filter house and clamp plate together or at the in-process that outwards extracts from the periphery of lower filter house and clamp plate with pressing from both sides the cover, because the edge of clamp plate and the internal face of pressing from both sides the cover are kept apart by the arch, even clamp plate and filter membrane do not pass through welded fastening, insert and the in-process of extracting, the clamp plate can not slide along with pressing from both sides the cover together, relative slip can not take place for clamp plate and filter membrane, can avoid causing the friction damage because of the relative slip between clamp plate and filter membrane to the surface of filter membrane, the protection filter membrane, ensure that the centrifuging tube provides stable filter.

Furthermore, the front side and the rear side of the lower filtering part are respectively provided with an opening, and the number of the sealing grooves, the sealing rings, the pressing plates and the filtering membranes is 2.

The utility model provides a centrifugal filter, the preceding, the back both sides of the lower filter house of centrifuging tube respectively are equipped with an opening, and two open-ended outsides respectively are equipped with a filter membrane, and two filter membranes can provide bigger filter area and bigger pollutant carrying capacity to improve filtration rate, solve the problem that current centrifugal filter pollutant carrying capacity is little, filtration rate is low.

Furthermore, the included angle between the plane where the opening is located and the vertical center line of the centrifugal tube is 1-5 degrees, and the distance between the upper end of the filter membrane and the vertical center line of the centrifugal tube is larger than the distance between the lower end of the filter membrane and the vertical center line of the centrifugal tube.

Research shows that when the included angle between the plane of the opening and the vertical center line of the centrifugal tube is 1-5 degrees, namely after the installation is completed, the included angle between the filter membrane and the vertical center line of the centrifugal tube is 1-5 degrees, and the distance between the upper end of the filter membrane and the vertical center line of the centrifugal tube is larger than that between the lower end of the filter membrane and the vertical center line of the centrifugal tube, namely the filter membrane is approximately positioned into a funnel-shaped structure, the tangential flow effect of fluid during centrifugation is facilitated, and the filtration rate is accelerated.

Further, the thickness of the starting end of the two side walls is larger than that of the bottom wall.

When the thickness of the initiating terminal of lateral wall is greater than the thickness of diapire, the thickness of the initiating terminal of lateral wall is also greater than its terminal thickness, and the distance of the vertical center line of the initiating terminal of lateral wall and centrifuging tube is greater than its terminal distance with the vertical center line of centrifuging tube promptly, and its purpose is to ensure that the filter membrane is roughly funnel-shaped structure after installing to be favorable to the tangential flow effect of fluid during the centrifugation.

Furthermore, the inner surface of the pressing plate is provided with a plurality of flow guide ribs.

The inner surface of the pressing plate is provided with a plurality of flow guide ribs, and during centrifugal filtration, liquid which reaches the downstream side of the filter membrane through the filter membrane can flow downwards along the flow guide ribs on the inner surface of the pressing plate and is finally discharged through a plurality of penetrating fluid outlets at the lower end of the pressing plate.

Furthermore, at least one exhaust hole is formed in the upper end of the flow guide rib of the pressing plate, and the exhaust hole is communicated with the flow guide rib in a fluid mode.

When gas accumulates on the downstream side of the filter membrane, the pressure on the downstream side increases, which causes a rapid decrease in the filtration rate, and even prevents the solvent on the upstream side of the filter membrane from permeating through the filter membrane. The utility model provides a centrifugal filter is equipped with the exhaust hole in the upper end of the water conservancy diversion muscle of clamp plate to, exhaust hole and water conservancy diversion muscle fluid intercommunication, the gas of gathering in the downstream side of filter membrane rises fast, reachs the exhaust hole and discharges along the water conservancy diversion muscle, thereby accelerates centrifugal filtration speed.

Furthermore, a liquid guide groove is arranged at the bottom end of the flow guide rib of the pressing plate and is in fluid communication with a penetrating fluid outlet of the pressing plate.

The solvent which reaches the downstream side of the filter membrane through the filter membrane flows downwards along the diversion ribs, reaches the liquid guide groove at the bottom end of the diversion ribs, and is discharged through a penetrating fluid outlet which is communicated with the liquid guide groove in a fluid mode.

Furthermore, the thickness of the upper end of the pressure plate is larger than that of the lower end of the pressure plate.

Because the thickness of the upper end of the pressing plate is larger than that of the lower end, the pressing plate and the filter membrane can bear the stronger squeezing action of the clamping sleeve only in the final stage of inserting the lower filtering part and the pressing plate into the clamping sleeve together or in the initial stage of pulling the clamping sleeve out from the peripheries of the lower filtering part and the pressing plate, so that the installation and the disassembly operations are easier, and meanwhile, the squeezing action force of the filter membrane in the operation process is reduced, and the filter membrane is protected.

The utility model provides a centrifugal filter, including the centrifuging tube, a pressing plate, filter membrane and clamp cover, the centrifuging tube includes upper tube portion and lower filter part, upper tube portion and lower filter part an organic whole are formed and are constituted fluid intercommunication, the top of upper tube portion has the entry, lower filter part preceding, at least one in the back both sides is equipped with the opening, be equipped with the seal groove around the open-ended, be equipped with the sealing washer in the seal groove, the filter membrane is pressed and is held on the seal ring, the clamp plate is hugged closely in the low reaches surface of filter membrane, it has hollow inside to press from both sides the cover, lower filter part and clamp plate are inserted the hollow inside that presss from both sides the cover together, the internal face that presss from both sides the. The centrifugal filter realizes sealing by the extrusion effect of the jacket on the pressing plate, the filter membrane and the sealing ring, can realize the fixed sealing of the filter membrane without additional hot melting or adhesive bonding, can avoid damaging the filter membrane, prevents leakage and adhesive dissolution, simplifies the manufacturing process of the centrifugal filter, and reduces the production cost.

Drawings

The present invention will be further explained with reference to the accompanying drawings:

fig. 1 is a completely exploded schematic view of a first centrifugal filter provided by the present invention;

FIG. 2 is a cross-sectional view of a centrifuge tube of the centrifugal filter provided in FIG. 1;

FIG. 3 is a schematic view of a partially exploded structure of the centrifugal filter provided in FIG. 1;

FIG. 4 is a cross-sectional view of the FIG. 1 centrifugal filter after assembly is complete;

FIGS. 5a and 5b are schematic views showing the structure of a pressure plate of the centrifugal filter provided in FIG. 1;

FIGS. 6a and 6b are an isometric view and a top view of the collet shown in FIG. 1;

fig. 7 is a fully exploded schematic view of a second centrifugal filter according to the present invention;

FIG. 8 is a cross-sectional view of the FIG. 7 centrifugal filter after assembly is complete;

FIG. 9 is a cross-sectional view of a centrifuge tube of the centrifugal filter provided in FIG. 7; the device comprises a centrifuge tube 1, an upper tube 10, an inlet 100, a lower filter part 11, a side wall 110, a bottom wall 111, a retentate chamber 112, an opening 113, a sealing groove 114, a bulge 115, a pressure plate 2, a permeate outlet 20, a flow guide rib 21, an exhaust hole 22, a liquid guide groove 23, a gas guide groove 24, a liquid discharge groove 25, a gas discharge groove 26, a filter membrane 3, a sealing ring 4 and a jacket 5.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention more clearly understood, the present invention will be described in further detail with reference to the accompanying drawings and detailed description. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

The first centrifugal filter shown in fig. 1 comprises a centrifuge tube 1, a pressure plate 2, a filter membrane 3, a sealing ring 4 and a jacket 5, wherein the centrifuge tube 1 comprises an upper tube part 10 and a lower filter part 11, and the upper tube part 10 and the lower filter part 11 are integrally formed and form fluid communication.

As shown in fig. 2-3, the top end of the upper tube part 10 of the centrifuge tube 1 has an inlet 100, and the biological sample to be concentrated and purified is injected into the interior of the centrifuge tube 1 through the inlet 100.

The lower filtering portion 11 comprises two side walls 110 extending from the bottom end of the upper tube portion 10 in a downward inclined manner and a bottom wall 111 connecting the two side walls 110, wherein an included angle between the front surfaces of the two side walls 110 and the vertical center line of the centrifuge tube 1 is 1-5 °, preferably 3 °, the extending direction of the bottom wall 111 is perpendicular to the vertical center line of the centrifuge tube 1, the thickness of the starting ends of the two side walls 110 is greater than that of the tail end and the bottom wall 111, and the distance between the outer edges of the starting ends of the two side walls 110 is greater than that of the outer edges of the tail end.

The hollow interior of the lower filter part 11 is a retentate chamber 112, the front side of the lower filter part 11 (i.e. the front surface side of the side wall 110) is provided with an opening 113, and the included angle between the plane of the opening 113 and the vertical center line of the centrifuge tube 1 is also 1 to 5 °, or, preferably, 3 °. An annular sealing groove 114 is arranged around the opening 113, a sealing ring 4 is arranged in the sealing groove 114, and the filter membrane 3 is pressed on the sealing ring 4. Alternatively, to improve the sealing effect of the filter membrane 3, two or more annular sealing grooves 114 may be provided around the opening 113, and one sealing ring 4 may be disposed in each sealing groove 114, and the filter membrane 3 is pressed against these sealing rings 4.

The rear side of the lower filter house 11 is a closed arc-shaped wall surface connecting the rear surfaces of the two side walls 110 and the rear surface of the bottom wall 111. The outer edges of the left and right sides of the sealing groove 114 are respectively provided with a protrusion 115, that is, a total of 2 protrusions 115 are provided. Since the seal groove 114 is located around the opening 113 and the opening 113 is located on the front side of the lower filter portion 11, that is, the front surface side of the side walls 110, the two protrusions 115 are also located on the front surface sides of the side walls 110, and the two protrusions 115 extend along the side walls 110 by a certain length.

The width of the pressure plate 2 is less than the distance between the outer edges of the two side walls 110, and the height of the protrusion 115 protruding from the sealing ring is greater than the thickness of the filter membrane. In addition, the width of the pressure plate 2 is exactly equal to the width of the filter membrane 3 and the distance between the inner edges of the two protrusions 115, so that the pressure plate 2 can be quickly positioned along the inner edges of the two protrusions 115 during installation and completely cover and press the entire surface of the filter membrane 3, and after the installation is completed, the two edges of the pressure plate 2 contact and abut against the inner edges of the two protrusions 115. In addition, in the process of inserting the lower filtering part 11 and the pressing plate 2 into the hollow interior of the jacket 5 together or in the process of pulling the jacket 5 out of the outer peripheries of the lower filtering part 11 and the pressing plate 2, because the two edges of the pressing plate 2 and the inner wall surface of the jacket 5 are separated by the protrusion 115, even if the pressing plate 2 and the filter membrane 3 are not fixed, the pressing plate 2 cannot slide together with the jacket 5, the pressing plate 2 and the filter membrane 3 cannot slide relatively, the friction damage to the surface of the filter membrane 3 due to the relative sliding between the pressing plate 2 and the filter membrane 3 can be avoided, the filter membrane 3 is protected, and the centrifugal filter can provide a stable filtering effect.

As shown in fig. 4, the first centrifugal filter is in a completely installed state, a sealing ring 4 is arranged in the sealing groove 114, the filter membrane 3 is pressed and held on the sealing ring 4, an included angle between the filter membrane 3 and the vertical center line of the centrifugal tube 1 is 1 to 5 degrees, or, better, the included angle is 3 degrees, and the distance between the upper end of the filter membrane 3 and the vertical center line of the centrifugal tube 1 is greater than the distance between the lower end of the filter membrane 3 and the vertical center line of the centrifugal tube 1.

The inner surface of the pressing plate 2 is tightly attached to the downstream surface of the filter membrane 3, the lower filtering part 11 and the pressing plate 2 are tightly clamped in the hollow inner part of the jacket 5, and the jacket 5 tightly presses the pressing plate 2, the filter membrane 3 and the sealing ring 4 to realize sealing, so that the upstream side and the downstream side of the filter membrane 3 are separated. The centrifugal filter realizes sealing by the extrusion effect of the jacket 5 on the pressing plate 2, the filter membrane 3 and the sealing ring 4, can realize fixed sealing on the filter membrane 3 without additional hot melting or adhesive bonding, can avoid damaging the filter membrane 3, prevents leakage and adhesive dissolution, simplifies the manufacturing process of the centrifugal filter, and reduces the production cost. In addition, the filter membrane 3 can be replaced, and other parts can be reused.

Because the distance between the upper end of the filter membrane 3 and the vertical center line of the centrifuge tube 1 is larger than the distance between the lower end of the filter membrane 3 and the vertical center line of the centrifuge tube 3 in the installation state, namely the filter membrane 3 is obliquely positioned relative to the vertical center line of the centrifuge tube 1 and is approximately in a funnel-shaped structure, the tangential flow of fluid in the centrifugation process is facilitated. And when the included angle between the filter membrane 3 and the vertical central line of the centrifugal tube 1 is 1-5 degrees, the promotion effect on the tangential flow of fluid in the centrifugal process is better, the centrifugal filtration speed is higher, and the service life of the filter membrane 3 is long. When the included angle between the filter membrane 3 and the vertical central line of the centrifugal tube 1 is 3 degrees, the promotion effect on the tangential flow of fluid in the centrifugal process is the best, and the centrifugal filtration rate is the fastest.

The internal surface of clamp plate 2 is the plane, and under the installation condition, the inclination of the internal surface of clamp plate 2 for the vertical central line of centrifuging tube 1 equals with the inclination of the front surface of two lateral walls 110 for the vertical central line of centrifuging tube 1, presss from both sides cover 5 and tightly presses clamp plate 2, and the external surface of clamp plate 2 closely laminates with the internal face that presss from both sides cover 5, and the internal surface of clamp plate 2 sticiss filter membrane 3 and sealing washer 4, realizes sealedly.

The thickness of the upper end of the pressure plate 2 is greater than that of the lower end, so that the pressure plate 2 and the filter membrane 3 are subjected to a relatively strong pressing action of the jacket 5 only at the final stage of inserting the lower filtering portion 11 and the pressure plate 2 together into the hollow interior of the jacket 5 or at the initial stage of pulling the jacket 5 outward from the outer peripheries of the lower filtering portion 11 and the pressure plate 2, and therefore, the mounting and dismounting operations are easier, and the pressing force applied to the filter membrane 3 during the operation is also reduced, thereby preventing the filter membrane 3 from being crushed.

As shown in fig. 5a and 5b, the inner surface of the pressing plate 2 is provided with a plurality of flow guiding ribs 21, the upper end of the flow guiding ribs 21 is provided with at least one exhaust hole 22 and an air guiding groove 24 in fluid communication with the exhaust hole 22, the air guiding groove 24 extends transversely, the bottom end of the flow guiding ribs 21 is provided with a plurality of penetrating fluid outlets 20 and liquid guiding grooves 23, the liquid guiding grooves 23 extend transversely, and the liquid guiding grooves 23 are in fluid communication with the penetrating fluid outlets 20 of the pressing plate 2. Wherein, the exhaust holes 22 and the penetrating fluid outlet 20 penetrate the whole wall thickness of the pressing plate 2, the air guide grooves 24 and the liquid guide grooves 23 are positioned on the inner surface of the pressing plate 2, and the air guide grooves and the liquid guide grooves are formed as grooves which do not penetrate the whole wall thickness of the pressing plate 2 and are respectively positioned at the upper end and the lower end of the flow guide ribs 21.

The outer surface of the platen 2 may be a curved surface as shown in the drawing or a flat surface. After the centrifugal filter is installed, the inner wall surface of the jacket 5 is closely attached to the outer surface of the pressure plate 2 with almost no gap, so that gas and liquid flowing out from the gas discharge holes 22 and the permeate discharge port 20 to the outer surface of the pressure plate 2 can rapidly flow out from between the inner wall surface of the jacket 5 and the outer surface of the pressure plate 2, the gas discharge grooves 26 are further provided above the gas discharge holes 22, and the plurality of liquid discharge grooves 25 are further provided below the permeate discharge port 20. Wherein, the drain groove 25 is a groove which does not penetrate through the whole wall thickness of the pressure plate 2, is positioned on the outer surface of the pressure plate 2 and extends downwards from the penetrating fluid outlet 20 to the bottom end of the pressure plate 2; the vent grooves 26 are grooves that do not penetrate the entire wall thickness of the platen 2, are located on the outer surface of the platen 2, and extend upward from the vent holes 22 to the top end of the platen 2. In the centrifugal filtration process, the gas and liquid reaching the space between the downstream side of the filter membrane 3 and the inner surface of the pressure plate 2 flow upwards and downwards along the flow guide ribs 21 into the gas guide groove 24 and the liquid guide groove 23, then the gas flows out through the exhaust holes 22 to reach the exhaust groove 26 at the upper end of the outer surface of the pressure plate 2, and finally is exhausted; the liquid is discharged through the permeate discharge port 20 to a plurality of drain grooves 25 at the lower end of the outer surface of the platen 2.

As shown in fig. 6a and 6b, the jacket 5 is a hollow cylinder, or the jacket 5 may have another hollow shape. The inner wall surface of the hollow inner part of the jacket 5 comprises a front arc surface, a rear arc surface and two inclined planes which are connected with the two ends of the two arc surfaces, wherein one arc surface is matched and attached with the outer surface of the arc surface shape of one pressing plate 2, the other arc surface is matched and attached with the closed arc wall surface which is connected with the rear surfaces of the two side walls 110 and the rear surface of the bottom wall 111, and the two inclined planes are matched and attached with the two side surfaces of the two side walls 110 of the lower filtering part 11.

The second centrifugal filter shown in fig. 7 comprises a centrifuge tube 1, two pressing plates 2, two filter membranes 3, two sealing rings 4 and a jacket 5, wherein the centrifuge tube 1 comprises an upper tube part 10 and a lower filter part 11, and the upper tube part 10 and the lower filter part 11 are integrally formed and form fluid communication.

As shown in fig. 8-9, the top end of the upper tube part 10 of the centrifuge tube 1 has an inlet 100, and the biological sample to be concentrated and purified is injected into the interior of the centrifuge tube 1 through the inlet 100.

The lower filtering portion 11 comprises two side walls 110 extending from the bottom end of the upper tube portion 10 in a downward inclined manner and a bottom wall 111 connecting the two side walls 110, wherein the included angles between the front and rear surfaces of the two side walls 110 and the vertical center line of the centrifuge tube 1 are all 1-5 °, preferably 3 °, the extending direction of the bottom wall 111 is perpendicular to the vertical center line of the centrifuge tube 1, the thickness of the starting ends of the two side walls 110 is greater than that of the end and the bottom wall 111, and the distance between the outer edges of the starting ends of the two side walls 110 is greater than that of the end.

The hollow interior of the lower filtering part 11 is a retentate chamber 112, the front side and the rear side of the lower filtering part 11 (i.e. the front surface side and the rear surface side of the two side walls 110) are respectively provided with an opening 113, and the included angle between the plane of the two openings 113 and the vertical center line of the centrifuge tube 1 is 1 to 5 degrees, or more preferably 3 degrees. An annular sealing groove 114 is respectively arranged around the two openings 113, a sealing ring 4 is respectively arranged in each sealing groove 114, and the two filter membranes 3 are respectively pressed on the two sealing rings 4. Alternatively, to improve the sealing effect of the filter membrane 3, two or more annular sealing grooves 114 may be provided around each opening 113, and one sealing ring 4 may be disposed in each sealing groove 114, and the filter membrane 3 is pressed against these sealing rings 4. In addition, the outer edges of the left and right sides of the two sealing grooves 114 are respectively provided with a protrusion 115, that is, a total of 4 protrusions 115 are provided. Since the two seal grooves 114 are located around the two openings 113, respectively, and the two openings 113 are located on the front and rear sides of the lower filter part 11, i.e., the front surface side and the rear surface side of the side wall 110, respectively, the 4 protrusions 115 are also located on the front surface side and the rear surface side of the side wall 110, respectively, and the 4 protrusions 115 extend along the two side walls 110 by a certain length.

The structure of the pressure plate 2 in the second centrifugal filter is the same as that of the pressure plate 2 in the first centrifugal filter, and the description is omitted. The front and rear arc surfaces of the inner wall surface of the hollow interior of the jacket 5 in the second centrifugal filter are respectively matched and attached to the outer surfaces of the two pressing plates 2, and the two inclined planes are matched and attached to the two side surfaces of the two side walls 110 of the lower filter part 11.

As shown in fig. 8, in the second centrifugal filter in the installation state, two seal grooves 114 are respectively provided with one seal ring 4, two filter membranes 3 are respectively pressed on the two seal rings 4, the included angle between the vertical central lines of the two filter membranes 3 and the centrifuge tube 1 is 1-5 °, or, better, the included angle is 3 °, and the distance between the upper ends of the two filter membranes 3 and the vertical central line of the centrifuge tube 1 is greater than the distance between the lower ends thereof and the vertical central line of the centrifuge tube 1.

The inner surfaces of the two pressing plates 2 are respectively clung to the downstream surfaces of the two filter membranes 3, the lower filtering part 11 and the two pressing plates 2 are tightly clamped in the hollow inner part of the jacket 5, the jacket 5 tightly presses the two pressing plates 2, the two filter membranes 3 and the two sealing rings 4 to realize sealing, and then the upstream side and the downstream side of the two filter membranes 3 are separated. This centrifugal filter realizes sealed through the squeezing action of pressing from both sides cover 5 to two clamp plates 2, two filter membranes 3 and two sealing washers 4, does not need extra hot melt or adhesive bonding just can realize the fixed seal to filter membrane 3, not only can avoid haring filter membrane 3, prevents to leak and the emergence that the adhesive dissolves out, has still simplified centrifugal filter's manufacturing process, reduces the manufacturing cost. In addition, the filter membrane 3 can be replaced, and other parts can be reused.

Because under the installation state, the distance between the upper ends of the two filter membranes 3 and the vertical central line of the centrifuge tube 1 is greater than the distance between the lower ends of the two filter membranes 3 and the vertical central line of the centrifuge tube 3, namely, the two filter membranes 3 are obliquely positioned relative to the vertical central line of the centrifuge tube 1 and are approximately funnel-shaped structures, which is favorable for the tangential flow of fluid in the centrifugation process. And when the included angles between the two filter membranes 3 and the vertical central line of the centrifugal tube 1 are all 1-5 degrees, the promotion effect on the tangential flow of fluid in the centrifugal process is better, the centrifugal filtration speed is higher, and the service life of the filter membranes 3 is long. When the included angles between the two filter membranes 3 and the vertical central line of the centrifuge tube 1 are both 3 degrees, the promotion effect on the tangential flow of fluid in the centrifugation process is the best, and the speed of centrifugal filtration is the fastest.

The internal surface of clamp plate 2 is the plane, and under the mounted state, the inclination of the internal surface of two clamp plates 2 for the vertical central line of centrifuging tube 1 equals with the inclination of the front surface of two lateral walls 110 and the vertical central line of back surface for centrifuging tube 1 respectively, presss from both sides cover 5 and tightly presses two clamp plates 2, and the internal surface of two clamp plates 2 all closely laminates with the internal face that presss from both sides cover 5, and the internal surface of two clamp plates 2 sticiss filter membrane 3 and sealing washer 4, realizes sealedly.

The thickness of the upper ends of the two pressing plates 2 is greater than that of the lower ends, so that the pressing plates 2 and the filter membrane 3 are subjected to a relatively strong pressing action of the jacket 5 only at the final stage of inserting the lower filtering part 11 and the two pressing plates 2 together into the hollow interior of the jacket 5 or at the initial stage of pulling the jacket 5 out of the outer peripheries of the lower filtering part 11 and the pressing plates 2, and therefore, the mounting and dismounting operations are easier, and the pressing action force applied to the filter membrane 3 during the operation is also reduced, thereby avoiding crushing the filter membrane 3.

The preferred embodiments of the present invention have been described in detail, but it should be understood that various changes and modifications can be made by those skilled in the art after reading the above teaching of the present invention. Such equivalents are intended to fall within the scope of the claims appended hereto.

Claims

1. The utility model provides a centrifugal filter, includes centrifuging tube, clamp plate and filter membrane, the centrifuging tube include upper hose portion and lower filter unit, upper hose portion and lower filter unit an organic whole form and constitute fluid communication, the top of upper hose portion have an entry, lower filter unit include from two lateral walls of the bottom downwardly extending of upper hose portion and the diapire of connecting two lateral walls, preceding, the back both sides of lower filter unit in at least one be equipped with opening, its characterized in that: centrifugal filter still have and press from both sides the cover, the cover that presss from both sides have hollow inside, the open-ended around be equipped with annular seal groove, the seal groove in be equipped with the sealing washer, the filter membrane press and hold on the sealing washer, the clamp plate hug closely in the downstream surface of filter membrane, the lower extreme of clamp plate be equipped with the penetrant export, lower filter house and clamp plate insert the hollow inside that presss from both sides the cover together, the internal face of clamp cover closely laminate with the surface of clamp plate and lower filter house.

2. The centrifugal filter of claim 1, wherein the width of the pressure plate is less than the distance between the outer edges of the two sidewalls.

3. The centrifugal filter of claim 2, wherein the outer edges of the left and right sides of the sealing groove are respectively provided with a protrusion, the protrusion protrudes out of the sealing ring by a height greater than the thickness of the filter membrane, and two edges of the pressure plate are in contact with and abut against the inner edges of the two protrusions.

4. The centrifugal filter according to claim 1, 2 or 3, wherein the lower filter portion has an opening at each of front and rear sides thereof, and the number of the sealing grooves, the sealing rings, the pressing plates and the filter membranes is 2.

5. The centrifugal filter of claim 1, 2 or 3, wherein the plane of the opening forms an angle of 1 ° to 5 ° with the vertical centerline of the centrifuge tube, and the distance between the upper end of the filter membrane and the vertical centerline of the centrifuge tube is greater than the distance between the lower end of the filter membrane and the vertical centerline of the centrifuge tube.

6. The centrifugal filter of claim 5, wherein the beginning of the two sidewalls has a thickness greater than the thickness of the bottom wall.

7. The centrifugal filter of claim 1 or 2, wherein the inner surface of the pressure plate has a plurality of flow-guiding ribs.

8. The centrifugal filter of claim 7 wherein at least one vent opening is formed in the upper end of the ribs of the pressure plate, said vent opening being in fluid communication with the ribs.

9. The centrifugal filter of claim 7 wherein a fluid-directing channel is provided at the bottom end of the ribs of the pressure plate, the fluid-directing channel being located on the inner surface of the pressure plate and in fluid communication with the permeate outlet of the pressure plate.

10. The centrifugal filter of claim 1 or 2, wherein the pressure plate has an upper end with a thickness greater than a thickness of a lower end.