CN111870259B - Blood collection serum separation needle for animals - Google Patents

Abstract

The invention discloses an animal blood collection serum separation needle, which comprises a needle body, a filtering membrane and a collection container, wherein the needle body comprises a needle tube and a piston main body, and is provided with a liquid inlet arranged on the needle tube, a liquid outlet arranged on the piston main body and a liquid storage cavity communicated with the liquid inlet and the liquid outlet; the filtering membrane divides the liquid storage cavity into a first cavity and a second cavity, and is used for filtering out serum in blood in the first cavity into the second cavity; the collection container is connected with the second chamber in an on-off mode. In the invention, the liquid inlet is formed on the needle tube and the liquid outlet on the piston main body, thereby being convenient for direct circulation of blood or serum in the liquid storage cavity while enlarging the liquid storage space of the liquid storage cavity; the filtering membrane is arranged in the liquid storage cavity, and serum can be directly separated without transferring blood; the collection container can be communicated with the second chamber on-off, and after the serum is fully separated out, the serum can be directly collected through communicating with the second chamber. The invention has the advantages of convenient operation and effectively avoiding sample pollution.

Description

Animal blood collection serum separation needle

Technical field

The invention relates to the technical field of animal blood collection, and in particular to a serum separation needle for animal blood collection.

Background technique

The current method of obtaining animal serum is generally to first use a syringe to draw an animal blood sample; then transfer the drawn animal blood sample to a centrifuge tube, and then place the centrifuge tube in a centrifuge to separate the serum, or place it in a blood collection tube to wait for separation layer; finally, the tester uses a pipette or pipette to suck out the separated serum and transfer it to a sample tube for storage. The existing method of obtaining animal serum requires transferring samples multiple times, and the process is cumbersome, which can easily lead to sample contamination and affect test results.

Contents of the invention

The main purpose of the present invention is to propose a serum separation needle for animal blood collection, aiming to solve the problem of cumbersome processes in obtaining animal serum in traditional technologies.

In order to achieve the above object, the present invention proposes an animal blood collection serum separation needle, including:

The needle body includes a needle tube and a piston body that is movable in the needle tube along an inward and outward direction. The needle body has a liquid inlet provided on the needle tube, a liquid outlet provided on the piston body, and a liquid outlet connected to the piston body. The liquid storage cavity of the liquid inlet and the liquid outlet;

A filter membrane is provided in the liquid storage chamber to separate the liquid storage chamber into a first chamber and a second chamber arranged sequentially along the liquid passing direction. The filter membrane is used to separate the first chamber located in the liquid storage chamber. Serum in the blood in the chamber is filtered out into the second chamber; and,

The collection container can be connected to the second chamber in an on-off manner.

Optionally, the needle tube has a liquid inlet chamber;

The filter membrane is disposed in the liquid inlet chamber and spaced apart from the liquid inlet.

Optionally, the needle tube has a liquid inlet chamber;

The piston body is provided with a liquid passage running through it in an inward and outward direction, the inlet of the liquid passage is connected to the liquid inlet chamber, and the outlet of the liquid passage constitutes the liquid outlet;

The filter membrane is located in the liquid passage.

Optionally, the filter membrane is detachably installed at the inner end of the piston body and covers the inlet of the liquid passage.

Optionally, an annular groove is formed on the inner end surface of the piston body around the outlet of the liquid passage;

The animal blood collection serum separation needle also includes a mounting ring, which is clamped in the annular groove to jointly limit the peripheral side of the filter membrane with the annular groove.

Optionally, the piston body is provided with a first baffle at the inlet of the liquid passage, and the first baffle is provided with a plurality of first passages connecting the liquid inlet chamber and the liquid passage. hole;

The filter membrane is arranged on the inner surface of the first baffle.

Optionally, the piston body includes a piston head and a piston rod. The piston head is provided with a threaded hole along the inner and outer directions. The piston rod is provided with the liquid passage along the inner and outer directions. The inlet of the piston rod is The first baffle is provided at the end;

The piston rod is threadedly matched with the threaded hole, so as to adjust the distance between the first baffle and the filter membrane by adjusting the threading depth of the two.

Optionally, the piston body includes a piston head and a piston rod. The piston head is provided with a threaded hole along the inner and outer directions. The inner end of the threaded hole is provided with the first baffle. The piston rod is provided with a threaded hole along the inner and outer directions. The liquid passage is provided in the direction, and the inlet end of the piston rod is provided with a second baffle. The second baffle is provided with a plurality of second passages connecting the liquid inlet chamber and the liquid passage. hole;

The piston rod is threadedly engaged with the threaded hole, so that the second baffle has a conductive state in which the second via hole is connected to the first via hole, and the second via hole is connected to the threaded hole. The first via hole is in a closed state.

Optionally, the piston hole is provided with a first limiting part, and the piston rod has a first fitting part, so that when the first fitting part rotates to abut against the first limiting part, the The second baffle is in the closed state; and/or,

The piston hole is provided with a second limiting part, and the piston rod has a second fitting part, so that when the second fitting part rotates to abut the second limiting part, the second baffle plate in the conductive state.

Optionally, the collection container is detachably connected to the outer end of the piston body.

In the technical solution provided by the present invention, the liquid inlet is formed on the needle tube and the liquid outlet is formed on the piston body, which not only expands the liquid storage space of the liquid storage chamber, but also facilitates the direct circulation of blood or serum in the liquid storage chamber; the filter membrane It is located in the liquid storage chamber and can directly separate blood without transferring blood; the collection container can be connected to the second chamber on and off. After the serum is fully analyzed, the serum can be directly collected by connecting to the second chamber. The invention has the advantages of easy operation and can effectively avoid sample contamination.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without exerting creative efforts.

Figure 1 is a schematic cross-sectional view of an embodiment of an animal blood collection and serum separation needle provided by the present invention, in which the second baffle is in a closed state;

Figure 2 is an enlarged schematic diagram of position A in Figure 1;

Figure 3 is a schematic cross-sectional view of the animal blood collection serum separation needle in Figure 1, in which the second baffle is in a conductive state;

Figure 4 is an enlarged schematic diagram of position B in Figure 3;

Figure 5 is an enlarged schematic diagram of position C in Figure 4.

Explanation of reference numbers:

label name label name 100 Animal blood collection serum separation needle twenty two Piston rod 10 Needle 221 Liquid outlet 11 liquid inlet 222 Liquid passage 12 Liquid inlet chamber 223 Second baffle twenty one Piston head 224 Second via 211 annular groove 30 filter membrane 212 first baffle 40 collection container 213 first via 50 Mounting ring

The realization of the purpose, functional features and advantages of the present invention will be further described with reference to the embodiments and the accompanying drawings.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention.

It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), then the directional indications are only used to explain the position of a certain posture (as shown in the drawings). The relative positional relationship, movement conditions, etc. between the components under the display). If the specific posture changes, the directional indication will also change accordingly.

In addition, if there are descriptions involving “first”, “second”, etc. in the embodiments of the present invention, the descriptions of “first”, “second”, etc. are only for descriptive purposes and shall not be understood as indications or implications. Its relative importance or implicit indication of the number of technical features indicated. Therefore, features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In addition, the meaning of "and/or" appearing in the entire text includes three parallel solutions. Taking "A and/or B" as an example, it includes solution A, or solution B, or a solution that satisfies both A and B at the same time. In addition, the technical solutions in various embodiments can be combined with each other, but it must be based on the realization by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that such a combination of technical solutions does not exist. , nor within the protection scope required by the present invention.

The current method of obtaining animal serum is generally to first use a syringe to draw an animal blood sample; then transfer the drawn animal blood sample to a centrifuge tube, and then place the centrifuge tube in a centrifuge to separate the serum, or place it in a blood collection tube to wait for separation layer; finally, the tester uses a pipette or pipette to suck out the separated serum and transfer it to a sample tube for storage. The existing method of obtaining animal serum requires transferring samples multiple times, and the process is cumbersome, which can easily lead to sample contamination and affect test results.

In view of this, the present invention provides a serum separation needle for animal blood collection. Figures 1 to 5 are embodiments of the serum separation needle for animal blood collection provided by the present invention.

The present invention provides an animal blood collection serum separation needle 100, which is mainly used to collect animal blood and obtain serum in the animal blood.

Please refer to Figures 1 to 4. The animal blood collection and serum separation needle 100 includes a needle body, a filter membrane 30 and a collection container 40. The needle body includes a needle tube 10 and a piston movable in the inner and outer directions of the needle tube 10. The needle body has a liquid inlet 11 provided on the needle tube 10, a liquid outlet 221 provided on the piston body, and a liquid storage chamber communicating with the liquid inlet 11 and the liquid outlet 221. ; The filter membrane 30 is disposed in the liquid storage chamber to separate the liquid storage chamber into a first chamber and a second chamber arranged sequentially along the liquid passing direction. The filter membrane 30 is used to separate the liquid storage chamber located in the liquid storage chamber. The serum in the blood in the first chamber is filtered into the second chamber; the collection container 40 can be connected to the second chamber in an on-off manner.

In the technical solution provided by the present invention, the liquid inlet 11 is formed on the needle tube 10 and the liquid outlet 221 is formed on the piston body, which not only expands the liquid storage space of the liquid storage chamber, but also facilitates liquid storage. Direct circulation of blood or serum in the cavity; the filter membrane 30 is located in the liquid storage cavity, and the blood can be directly separated without transferring blood; the collection container 40 can be connected to the second chamber on and off, After the serum is fully analyzed, the serum can be collected directly by connecting the second chamber. The invention has the advantages of easy operation and can effectively avoid sample contamination.

The specific structure of the needle body can be referred to existing syringes, which usually include a needle tube 10 and a piston body. The needle tube 10 has a liquid inlet 11 at the top, and the liquid inlet 11 can be detachably connected to a needle of required specifications. ; The needle tube 10 is generally cylindrical, and a liquid inlet chamber 12 is formed in the needle tube 10; the piston body includes a piston head 21 and a piston rod 22, and the piston head 21 is accommodated in the liquid inlet chamber 12 inside, and cooperates with the piston of the liquid inlet chamber 12; the piston rod 22 is connected to the piston head 21, and at least part of it extends out of the liquid inlet chamber 12 to facilitate the operator's holding operation.

The piston body is reciprocally movable along a preset path in the liquid inlet chamber 12. For ease of understanding, it is defined below that the piston body is reciprocally movable along the inner and outer directions and is installed in the liquid inlet chamber 12, and the The direction from the piston head 21 to the piston rod 22 in the piston body is from inside to outside.

This design is different from conventional syringes in that a liquid passage 222 connected to the liquid inlet chamber 12 is provided on the piston body. Specifically, the liquid passage 222 is provided through the piston body in an inner and outer direction. The liquid channel 222 is provided with an inlet, and the inlet can be provided at the inner end of the piston head 21. The inlet of the liquid passage 222 is connected to the liquid inlet chamber 12 of the needle tube 10; the liquid passage 222 is provided with an outlet. , the outlet may be provided at the outer end of the piston rod 22 , and the outlet of the liquid passage 222 constitutes the liquid outlet 221 . The liquid inlet chamber 12 and the liquid passage 222 together constitute the liquid storage chamber, which helps to expand the liquid storage space as much as possible within the limited needle body, thereby further expanding the first chamber and The respective liquid storage spaces of the second chambers can provide more blood each time to more fully filter out the serum.

The filter membrane 30 separates the above-mentioned first chamber and the second chamber, so that when the needle is inserted into the animal's blood vessel, the animal's blood enters through the liquid inlet 11 under the action of the piston body. In the first chamber, after the preset time and preset angle have passed, the animal blood in the first chamber is affected by the filter membrane 30, and only the serum enters through the filter membrane 30. In the second chamber, serum is filtered out. The specific selection of the filter membrane 30 can refer to the existing technology and will not be described in detail here.

The collection container 40 can be a container of any specification and for any purpose, such as a serum sample tube; the collection container 40 is detachably connected to the piston rod 22 of the piston body, which facilitates the disassembly, assembly, and replacement of the collection container 40 ; The collection container 40 achieves a channelable connection with the second chamber by changing the relative positional relationship with the piston rod 22, or through an additional structure such as a control valve body, so that When the blood in the first chamber is not fully used, that is, the serum in the second chamber is not completely obtained, the collection container 40 is disconnected from the second chamber; conversely, when the third chamber is not fully obtained, the collection container 40 is disconnected from the second chamber. When the blood in one chamber is fully used, that is, when the serum in the second chamber is completely obtained, the collection container 40 is connected to the second chamber, which facilitates the centralized collection and processing of serum and can reduce the serum concentration. Possibility of contamination and deterioration.

The filter membrane 30 is disposed in the liquid storage chamber. In one embodiment, the filter membrane 30 is disposed in the liquid inlet chamber 12 and spaced apart from the liquid inlet 11 . The filter membrane 30 can be fixedly installed on the inner cavity wall of the needle tube 10 , or can be adjustably installed on the inner cavity wall of the needle tube 10 in the up and down direction through, for example, a chute and a slider structure. The filter membrane 30 is arranged in the liquid inlet chamber 12 so that the space size of the first chamber is fixed and a set amount of animal blood can be extracted.

In another embodiment, the filter membrane 30 is disposed in the liquid passage 222 , specifically, it can be disposed at the inlet of the liquid passage 222 , the middle part of the liquid passage 222 and the liquid outlet 221 at. The filter membrane 30 is arranged at the piston body, so that the pressure change in the liquid storage chamber caused by the piston movement of the piston body does not substantially affect the filter membrane 30, which helps to extend the filter membrane. In addition, the filter membrane 30 is disposed at the piston body, so that the filter membrane 30 can be more easily disassembled and replaced when the piston body is extracted from the needle tube 10 .

For ease of understanding, the following description takes the filter membrane 30 being disposed in the liquid passage 222 as an example.

Specifically, in this embodiment, the filter membrane 30 is detachably installed at the inner end of the piston body and covers the inlet of the liquid passage 222 . Compared with the technical solution of arranging the filter membrane 30 in the middle of the liquid passage 222, arranging the filter membrane 30 at the entrance of the liquid passage 222 is easier to disassemble and replace; The technical solution is that the filter membrane 30 is disposed at the liquid outlet 221. Disposing the filter membrane 30 at the entrance of the liquid passage 222 can effectively expand the liquid storage space of the second chamber, which is helpful. for adequate filtration of serum.

There are many ways to install the filter membrane 30 on the piston body, such as bonding and fixing. However, in order to avoid introducing other interfering impurities into the blood or serum, please refer to Figures 3 to 5. In this embodiment, , the inner end surface of the piston body is provided with an annular groove 211 around the outlet of the liquid passage 222; the animal blood collection serum separation needle 100 also includes a mounting ring 50, and the mounting ring 50 is clamped in the annular groove 211 to jointly limit the outer peripheral side of the filter membrane 30 with the annular groove 211 . The mounting ring 50 can be made of the same material as the piston head 21 , and when the mounting ring 50 and the annular groove 211 jointly limit the outer peripheral side of the filter membrane 30 , The inner end surface of the mounting ring 50 is flush with or smoothly transitions from the inner end surface of the piston head 21 to avoid interference with the piston movement of the piston head 21 . Of course, the mounting ring 50 can be made of a material different from that of the piston head 21 , and is stronger than the piston head 21 , which can enhance the strength of the piston head. The arrangement of the mounting ring 50 and the annular groove 211 enables quick disassembly and assembly of the filter membrane 30 .

Since the texture of the filter membrane 30 is relatively soft, when the filter membrane 30 covers the inlet of the liquid passage 222, the portion of the filter membrane 30 corresponding to the inlet of the liquid passage 222 is in a suspended state, making it easy to Damaged due to pressure changes in the liquid storage chamber.

Based on the above, in one embodiment, the piston body is provided with a first baffle 212 at the inlet of the liquid passage 222 , and the first baffle 212 is provided with a connection between the liquid inlet chamber 12 and the liquid inlet chamber 12 . A plurality of first via holes 213 of the liquid passage 222; the filter membrane 30 is provided on the inner surface of the first baffle 212. The first through hole 213 can realize the communication between the liquid passage 222 and the liquid inlet chamber 12. At the same time, the first baffle 212 can support the filter membrane 30, which helps In order to reduce the impact of pressure changes in the liquid storage chamber on the filter membrane 30 .

The first baffle 212 can be disposed on the piston head 21. Specifically, in one embodiment, the piston head 21 is provided with a threaded hole along the inner and outer directions, and the inlet end of the piston rod 22 is provided with a threaded hole. The first baffle 212; the piston rod 22 is threadedly matched with the threaded hole to adjust the distance between the first baffle 212 and the filter membrane 30 by adjusting the threading depth of the two. . By arranging the piston rod 22 to be threadedly matched with the threaded hole, the detachable connection between the piston rod 22 and the piston head 21 can be realized, and the piston rod 22 can rotate along its own axis at the same time. The movable stroke and the movable stroke along the inward and outward movements can extract the animal blood by the animal blood collection serum separation needle 100, that is, before the piston body forms a negative pressure in the liquid storage chamber through the inward and outward movements, Adjust the piston head 21 to rotate toward the piston head 21 , that is, adjust the first baffle 212 to move closer to the filter membrane 30 until it abuts the filter membrane 30 , thereby realizing the adjustment of the filter membrane. 30 support and protection; on the contrary, when the animal blood collection serum separation needle 100 has completed the blood drawing operation and needs to be left alone for the serum in the blood to be filtered out, the piston head 21 can be adjusted away from the piston head 21 Spin out, that is, adjust the first baffle 212 to move away from the filter membrane 30, increase the distance between the first baffle 212 and the filter membrane 30, and prevent the first baffle 212 from The filtration effect of the filter membrane 30 is reduced in the portion where the first via hole 213 is not opened.

Alternatively, the first baffle 212 can be provided on the piston rod 22. Please refer to Figures 1 to 4. In this embodiment, the piston head 21 is provided with a threaded hole running through it in an inner and outer direction. The inner end of the hole is provided with the first baffle 212, the piston rod 22 is provided with the liquid passage 222 along the inner and outer directions, and the inlet end of the piston rod 22 is provided with a second baffle 223. The second baffle 223 is provided with a plurality of second through holes 224 connecting the liquid inlet chamber 12 and the liquid passage 222; the piston rod 22 is screwed with the threaded hole, so that the second The baffle 223 rotates to a conductive state in which the second via hole 224 communicates with the first via hole 213 and a closed state in which the second via hole 224 and the first via hole 213 are closed. When the first baffle 212 is fixedly installed on the piston hole and the second baffle 223 is disposed on the piston rod 22, the second baffle 223 can be driven by the piston rod 22. The second baffle 223 rotates and moves inward and outward, and the rotation of the second baffle 223 can realize its switching between the conduction state and the cover state, that is, indirectly realize the connection between the collection container 40 and The on-off connection between the second chambers and the inward and outward movement of the second baffle 223 can extend and expand the space of the second chamber.

It should be noted that the arrangement manner of the plurality of first via holes 213 on the first baffle 212 and the arrangement manner of the plurality of second via holes 224 on the second baffle 223 can be The same arrangement is made, so that when the first baffle 212 and the second baffle 223 overlap, the plurality of first via holes 213 and the plurality of second via holes 224 are respectively connected, and the The two baffles 223 are in the conductive state; on the contrary, when the first baffle 212 and the second baffle 223 are offset by a certain angle, the plurality of first via holes 213 and the plurality of second The via holes 224 are respectively staggered and blocked, and the second baffle 223 is in a closed state. Specifically, the circular end surface of the first baffle 212 can be divided into a plurality of sector-shaped areas, wherein some of the sector-shaped areas are hollowed out to form the first via hole 213; the second baffle 223 and the The two via holes 224 are suitable for the first baffle 212 and the first via hole 213 .

Next, in this embodiment, the piston hole is provided with a first limiting portion, and the piston rod 22 has a first fitting portion, so that when the first fitting portion rotates to offset the first limiting portion When connected, the second baffle 223 is in the closed state; and/or the piston hole is provided with a second limiting part, and the piston rod 22 has a second fitting part to prevent the When the fitting part rotates to abut the second limiting part, the second baffle 223 is in the conductive state. The restriction of the first limiting part and the second limiting part can limit the specific stroke of rotation and movement of the piston rod 22, and accurately limit the second baffle 223 to reach the closing position. The position in the state and the position in which the second baffle 223 reaches the conduction state facilitate manual operation by the operator. The first limiting part and the second limiting part are, for example, limiting protrusions protruding in the threaded hole, which will not be described in detail here.

The above are only preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Under the inventive concept of the present invention, equivalent structural transformations can be made using the contents of the description and drawings of the present invention, or direct/indirect applications. Other related technical fields are included in the patent protection scope of the present invention.

Claims (1)

1. An animal blood collection serum separation needle, comprising:

the needle body comprises a needle tube and a piston main body movably arranged in the needle tube along the inner and outer directions, and the needle body is provided with a liquid inlet arranged in the needle tube, a liquid outlet arranged in the piston main body and a liquid storage cavity communicated with the liquid inlet and the liquid outlet;

the filtering membrane is arranged in the liquid storage cavity to divide the liquid storage cavity into a first cavity and a second cavity which are sequentially arranged along the liquid passing direction, and the filtering membrane is used for filtering out serum in blood in the first cavity into the second cavity; the method comprises the steps of,

the collection container is connected with the second chamber in an on-off mode;

the needle tube is provided with a liquid inlet cavity;

the filtering membrane is fixedly arranged on the inner cavity wall of the needle tube;

the piston main body is internally and externally penetrated with a liquid passing channel, an inlet of the liquid passing channel is communicated with the liquid inlet cavity, and an outlet of the liquid passing channel forms the liquid outlet; the liquid inlet cavity and the liquid passing channel jointly form the liquid storage cavity;

the piston main body comprises a piston head and a piston rod, a threaded hole is formed in the piston head along the inner side and the outer side in a penetrating mode, a first baffle is arranged at the inner end of the threaded hole, and a plurality of first through holes which are communicated with the liquid inlet cavity and the liquid passing channel are formed in the first baffle;

dividing the circular end face of the first baffle into a plurality of sector areas, wherein part of the sector areas are hollowed out to form the first via hole;

the first through hole can realize the communication between the liquid passing channel and the liquid inlet cavity; before negative pressure is formed in the liquid storage cavity by moving the piston main body from inside to outside, the first baffle is adjusted to approach the filtering membrane until the first baffle is abutted against the filtering membrane, so that the filtering membrane is supported and protected; when serum in blood is filtered out by standing, the first baffle is regulated to move away from the filtering membrane, so that the distance between the first baffle and the filtering membrane is increased;

the piston rod is internally and externally penetrated with the liquid passing channel, the inlet end of the piston rod is provided with a second baffle, and the second baffle is provided with a plurality of second through holes communicated with the liquid inlet cavity and the liquid passing channel; the second baffle and the second via are suitable for the arrangement of the first baffle and the first via; the second baffle can rotate and move inwards and outwards under the drive of the piston rod, and the rotation of the second baffle can realize the switching between a conducting state and a covering state; the second baffle moves inwards and outwards, so that the extension and expansion of the second chamber space can be realized;

the arrangement mode of the first through holes on the first baffle plate and the arrangement mode of the second through holes on the second baffle plate are the same, so that when the first baffle plate and the second baffle plate are overlapped, the first through holes are respectively communicated with the second through holes, and the second baffle plate is in a conducting state; when the first baffle plate and the second baffle plate are staggered by a certain angle, the first through holes and the second through holes are respectively staggered and are respectively shielded, and the second baffle plate is in a covering state;

the piston rod is in threaded fit with the threaded hole, so that the second baffle plate is in a conducting state of rotating to the second through hole to be communicated with the first through hole and a covering state of closing the second through hole and the first through hole;

the threaded hole is provided with a first limiting part, the piston rod is provided with a first matching part, and when the first matching part rotates to be abutted against the first limiting part, the second baffle is in the covering state; and/or the number of the groups of groups,

the threaded hole is provided with a second limiting part, the piston rod is provided with a second matching part, and when the second matching part rotates to be abutted against the second limiting part, the second baffle is in the conducting state; the first limiting part and the second limiting part are limiting protrusions protruding into the threaded holes;

the collection container is detachably connected with the outer end of the piston main body.