An automatic needle filter device and a filtering method

Abstract

The embodiment of the application provides an automatic needle type filtering device, which comprises a filtering assembly, a support assembly, a visual detection assembly, a liquid receiving assembly and a gas feeding assembly; wherein the filtering assembly comprises a needle cylinder and a filter matched with the needle cylinder; the support assembly is used for placing the filtering assembly; the visual detection assembly is arranged on one side of the needle cylinder in the horizontal direction and is used for detecting the liquid level in the needle cylinder; the liquid receiving assembly comprises a liquid receiving container which is received below the filter; and the gas feeding assembly is connected with the needle cylinder and is used for changing the air pressure of the needle cylinder to control the flow rate of the liquid in the needle cylinder. The automatic needle type filtering device of the embodiment of the application does not need manual participation, realizes automatic filtering, reduces the labor intensity, optimizes the working environment, and makes the automatic needle type filtering applied in the laboratory.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automation, in particular to an automatic needle type filtering device and a filtering method. BACKGROUND

[0002] In the experimental operation process in the fields of chemistry, biological medicine, molecular diagnosis, etc., a disposable syringe (with a piston) is often used to cooperate with a disposable needle type filter to filter a solution. At present, this method is generally used in manual filtering. After the piston of the syringe is pulled out manually, the syringe is combined with the filter, the solution is added to the syringe, the piston is inserted into the syringe, the outlet of the filter is directly aligned with a liquid storage container, and the piston is gradually pressed to make the solution pass through the filter into the container.

[0003] In order to meet the needs of experimental operation, there are two kinds of automatic filtering devices in the prior art. One is to clamp the syringe of the syringe filter assembly by a clamp, and after the solution is added to the syringe, the clamp above the syringe presses the syringe port to pass in gas, and the solution is directly passed into the container through the filter by using air pressure. This method cannot adapt to the complexity of sample filtration (some are very easy to filter, some are very difficult to filter, and the filtrate is filtered out in drops); it cannot be determined whether the solution in the barrel is filtered or not, which will directly affect the success or failure of the filtration; moreover, the filter below is not supported, and it is easy to fall off under the action of continuous air pressure in the syringe; the outlet of the filter is far away from the container for filtering the solution, and the solution at the outlet of the filter is easy to splash on the surrounding materials, which seriously pollutes the surrounding environment.

[0004] The other is to place the syringe filter assembly on a support plate, and after the solution is added to the syringe, the clamp above the syringe presses the syringe port to pass in gas, and the solution is directly passed into the container through the filter by using air pressure. This method solves the problem that the filter is easy to fall off from the syringe under the action of air pressure, but cannot solve other problems. For example, it cannot be detected whether the solution in the syringe is filtered or not, which will cause the device to continue to blow after the solution is filtered, resulting in the rapid evaporation of the filtered solution in the container, because most of the laboratory uses volatile organic solvents; it will also cause some difficult to filter sample solution to be filtered, which will cause the amount of filtrate to be insufficient, and the next process cannot be carried out, which will directly lead to the failure of the experiment and the waste of the sample.

[0005] Therefore, in view of the above problems, an automatic needle type filtering device is provided. SUMMARY

[0006] The technical problem to be solved by the embodiments of the present application is to provide an automatic needle type filtering device, which solves the problems of evaporation or insufficient filtering solution caused by inaccurate detection of the solution in the syringe, and has the advantages of wide application range and high automation degree.

[0007] To solve the above technical problems, the embodiment of the present application proposes an automatic needle type filtering device, comprising:

[0008] a filtering assembly comprising a needle cylinder and a filter matched with the needle cylinder;

[0009] a support assembly for placing the filtering assembly, the support assembly comprising a placing plate and a support column arranged at a corner of the placing plate, the placing plate being provided with a groove for placing the filter, the bottom of the groove having a through hole;

[0010] a visual detection assembly arranged horizontally on one side of the needle cylinder for detecting the liquid level in the needle cylinder;

[0011] a liquid receiving assembly comprising a liquid receiving container, the liquid receiving container being received below the filter;

[0012] a gas feeding assembly connected with the needle cylinder for changing the air pressure of the needle cylinder to control the flow rate of the liquid in the needle cylinder.

[0013] In some embodiments, the visual detection assembly comprises a camera and a light source, wherein the light source irradiates the needle cylinder, the liquid surface in the needle cylinder is imaged in the camera, and the liquid level in the needle cylinder is calculated based on the captured image to control the start and stop of the gas feeding assembly.

[0014] Preferably, the placing plate is elastically connected with the support column, in particular, a compression spring and a sliding ring are sleeved on the top of the support column, the sliding ring is arranged on the top of the compression spring, and the placing plate is connected with the sliding ring.

[0015] In some embodiments, the placing plate is further provided with an air claw, the air claw is arranged in cooperation with the needle cylinder to limit the movement of the needle cylinder, and the air claw partially surrounds the needle cylinder.

[0016] Further, the placing plate is further provided with a liquid absorbing cotton, and the liquid absorbing cotton is located horizontally on one side of the groove.

[0017] Further, the gas feeding assembly comprises a compression cylinder, a connecting plate, a pressure head and a gas path control system, one end of the connecting plate is connected with the output end of the compression cylinder, the other end is connected with the pressure head, the compression cylinder can move up and down and rotate by 90 degrees, and the gas path control system is connected with an air pressure and flow control system to meet different air pressure and flow parameter settings in sample filtering.

[0018] Further, the bottom of the pressure head connected with the needle cylinder is a conical structure, wherein the pressure head adopts air outlet at the bottom and air inlet at the side or top.

[0019] Further, the liquid receiving assembly further comprises a rotating arm, one end of the rotating arm is connected with a driving member, and the other end of the rotating arm is provided with a waste liquid tank for receiving waste liquid; the bottom of the waste liquid tank is provided with a flow guide pipeline in communication with the waste liquid tank.

[0020] The application further provides a filtering method applied to the automatic needle type filtering device, and the filtering method comprises the following steps:

[0021] The mechanical arm places the needle cylinder and the filter, which are assembled in advance, into the groove on the placement plate; the waste liquid tank on the rotating arm is moved to below the filter;

[0022] The needle cylinder is injected with a rinsing solution, the pressure head of the air feeding assembly is connected with the needle cylinder and feeds air into the needle cylinder, the liquid in the needle cylinder flows to the filter under the action of the air pressure, and then flows into the waste liquid tank and flows out through the flow guide pipeline;

[0023] After the needle cylinder is rinsed, the rotating arm is moved away from below the filter, and the liquid receiving container is moved to below the filter;

[0024] The needle cylinder is injected with the liquid to be filtered, the pressure head of the air feeding assembly is connected with the needle cylinder and drives the needle cylinder and the filter to move downward until the liquid outlet of the filter extends into the liquid receiving container, air is fed into the needle cylinder, the liquid in the needle cylinder flows to the filter under the action of the air pressure, and then flows into the liquid receiving container;

[0025] The visual detection assembly monitors the liquid level in the needle cylinder, and when the liquid level in the needle cylinder is monitored to be a preset threshold value, the air feeding assembly stops working, and the filtering is completed.

[0026] Further, the step of monitoring the liquid level in the needle cylinder by the visual detection assembly is as follows:

[0027] The light source irradiates the needle cylinder, the position of the camera and the parameters of the camera are adjusted, and the position of the camera is relatively static with the position of the needle cylinder; under the irradiation of the light source, the position of the liquid surface in the needle cylinder is clearly imaged in the camera;

[0028] During the filtering, as the liquid level in the needle cylinder drops, the position of the liquid surface in the needle cylinder is continuously changed in the imaging, the camera captures and collects images in real time, and the visual algorithm processes the images to calculate the liquid level in real time;

[0029] A control signal is output according to the calculated liquid level, when the liquid level drops to a preset value, it is determined that the filtering is completed, and an end signal is given.

[0030] The automatic needle type filter device in the embodiment of the application has simple structure, does not need manual participation, realizes automatic filtration, reduces labor intensity, optimizes working environment, and makes the automatic needle type filtration applied in the laboratory; the gas path control system accessing the gas pressure and flow control system can meet the complexity of sample filtration, and can be applied to filtration from easy to difficult; the device uses visual detection to distinguish the liquid level change in the needle cylinder, solves the problems of evaporation or insufficient filtration solution caused by inaccurate detection of the solution in the needle cylinder; the placement plate is elastically installed, and under the action of the pressing cylinder, the pressing head presses the needle cylinder downward during filtration, the liquid outlet head of the filter can be inserted into the liquid receiving container, and the falling and spatter pollution of the filter outlet can be prevented. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 is a whole structure schematic diagram of the automatic needle type filter device in the embodiment of the application;

[0032] Figure 2 is a whole structure schematic diagram of the automatic needle type filter device in the embodiment of the application;

[0033] Figure 3 is a structure schematic diagram of the filter in the embodiment of the application;

[0034] Figure 4 is a connection schematic diagram of the placement plate and the support column in the embodiment of the application;

[0035] Figure 5 is a structure schematic diagram of the support column in the embodiment of the application;

[0036] Figure 6 is a structure schematic diagram of the rotating arm in the embodiment of the application. DETAILED DESCRIPTION

[0037] It should be noted that the embodiments in the application and the features in the embodiments can be combined with each other without conflict, and the application will be further described in detail in combination with the drawings and specific embodiments.

[0038] In the embodiments of the application, if there is a directional indication such as up, down, left, right, front, back, …, it is only used to explain the relative position relationship, movement condition, etc. between components in a certain specific posture such as shown in the drawings, and if the specific posture changes, the directional indication also changes accordingly.

[0039] In addition, in the application, the description of "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features.

[0040] In the experimental operation process in the fields of chemistry, biological medicine, molecular diagnosis and the like, a bottle tube and the like container is often used to store liquid, wherein the bottle tube often needs to be opened and closed during use in order to realize the purpose of accessing the solution. However, the existing automatic opening and closing device has the problems of large volume, low integration, and is generally only suitable for closing a single container, and has problems of closing obliquely, closing a broken bottle, closing too tightly or too loosely and the like.

[0041] The automatic needle type filtering device of the embodiment of the present application is applied to the experimental operation process in the fields of chemistry, biological medicine, molecular diagnosis and the like, adopts visual detection to distinguish the liquid level change in the needle cylinder, can accurately detect whether the solution in the needle cylinder is filtered, solves the problems of evaporation or insufficient filtering solution caused by inaccurate detection of the solution in the needle cylinder, liberates the hands of the operating personnel in the laboratory, reduces the labor intensity, optimizes the working environment, and makes the automatic needle type filtering truly applied in the actual laboratory.

[0042] Hereinafter, the embodiment of the present application will be described in detail with reference to the accompanying drawings. Figure 1 is a schematic view showing the main part structure of the automatic needle type filtering device of the embodiment of the present application. The automatic needle type filtering device is composed of a filtering assembly 10, a support assembly 20, a visual detection assembly 30, a liquid receiving assembly 40 and a gas feeding assembly 50. The filtering assembly 10 includes a needle cylinder 11 and a filter 12 matched with the needle cylinder 11. The support assembly 20 is used to place the filtering assembly 10 and includes a placement plate 21 and a support column 22 arranged at the corner of the placement plate 21. The placement plate 21 is provided with a recess 211 for placing the filter 12, and the bottom of the recess 211 has a through hole 212. The visual detection assembly 30 is arranged horizontally at one side of the needle cylinder 11 and is used to detect the liquid level in the needle cylinder 11. The liquid receiving assembly 40 includes a liquid receiving container 41 which is received below the filter 12. The gas feeding assembly 50 is connected with the needle cylinder 11 and is used to change the air pressure in the needle cylinder 11 to control the flow rate of the liquid in the needle cylinder 11.

[0043] In specific applications, for example, Figure 1 and Figure 2As shown, the filter 12 is pre-placed in the groove 211 by a mechanical hand or manually, at which time the liquid outlet 1220 at the bottom of the filter 12 is located in the through hole 212, the filter is limited to avoid the filter 12 from falling off, the needle cylinder 11 is placed on the interface 1210 at the top of the filter 12 by a mechanical hand, at which time the liquid in the needle cylinder 11 flows out and enters the filter 12 and then flows out from the liquid outlet below the filter 12 to the liquid receiving container 41, when filtering, the air feeding assembly 50 is connected with the needle cylinder 11 and feeds air into the needle cylinder 11 to increase the air pressure in the needle cylinder 11, the liquid in the needle cylinder 11 flows to the filter 12 under the action of the air pressure, at this time, the visual detection assembly 30 monitors the change of the liquid level in the needle cylinder 11 in real time to detect whether the solution in the needle cylinder is filtered completely, when it is detected that the liquid in the needle cylinder 11 is filtered completely, the air feeding assembly 50 is simultaneously turned off to avoid the filtered solution in the container from evaporating quickly and to ensure that the filtered liquid is sufficient.

[0044] Further, as shown in Figure 2 The groove 211 is provided with a detection sensor for detecting whether the filter 12 is present or not, which is used to detect whether the filter 12 falls off during the carrying process of the mechanical arm or whether the filter 12 is left in the groove 211 after the mechanical arm takes away the needle cylinder 11, so as to avoid the failure to place the next needle cylinder filter.

[0045] In this embodiment, as shown in Figure 3 The filter 12 is a purchased part and belongs to laboratory consumables, which includes a detachable upper half 121 and a lower half 122, and the lower half is provided with filter paper at the top end. The upper half is provided with an interface 1210 connected with the needle cylinder 11, and the lower half is provided with a liquid outlet 1220; the needle cylinder 11 is laboratory consumables.

[0046] In some embodiments, the visual detection assembly includes a camera 31 and a light source 32, wherein the light source 32 irradiates the needle cylinder 11, the liquid level in the needle cylinder 11 is imaged in the camera 31, the height of the liquid level in the needle cylinder 11 is calculated through the collected image, and the air feeding assembly is controlled to be turned off.

[0047] In some embodiments, the placement plate 21 is elastically connected with the support column 22, specifically, the support column 22 is sleeved with a compression spring 23 and a sliding ring 24 at the top, the sliding ring 24 is arranged at the top of the compression spring 23, and the placement plate 21 is connected with the sliding ring 24.

[0048] In specific applications, the support 22 is designed with a step above and is provided with a compression spring 23, the compression spring 23 is connected with a sliding ring 24, at the beginning, the placing plate 21 stays at the upper end under the support of the compression spring 23, when the liquid receiving container 41 (such as a sample feeding bottle, a test tube, a waste liquid tank, etc.) moves to below the outlet of the filter 12, the air feeding assembly 50 rotates to press the needle cylinder 11, the compression spring 23 is compressed under the pressure, at the same time, the placing plate 21, the needle cylinder 11 and the filter 12 move downward by a distance until they are supported by the step shaft of the support 22, at this time, the outlet 1220 of the filter 12 just extends into the inside of the liquid receiving container 41 by a distance, which can avoid the liquid splashing outside the liquid receiving container 41 during the filtration, after the filtration is completed, the air feeding assembly 50 rotates to move away, under the action of the compression spring 23, the placing plate 21, the needle cylinder 11 and the filter 12 return to the starting position, which is convenient for the movement or replacement of the lower liquid receiving container 41.

[0049] In some embodiments, the placing plate 21 is further provided with an air claw 25, the air claw 25 is arranged in cooperation with the needle cylinder 11 to limit the movement of the needle cylinder 11, and the air claw 25 partially surrounds the needle cylinder 11. Specifically, the air claw 25 is installed on the placing plate 21, the air claw 25 is used for the relative positioning of the needle cylinder 11, which ensures that the needle cylinder 11 will not be tilted in the case of being pressed by the air feeding assembly 50, the air claw 25 does not contact the outer wall of the needle cylinder 11 and there is a certain gap, which allows the air feeding assembly 50 to adapt to the center deviation of the needle cylinder; at the same time, the air claw 25 partially surrounds the needle cylinder 11, that is, the side of the needle cylinder 11 facing the visual detection assembly 30 is not blocked by the air claw 25, which does not affect the detection space of the visual detection assembly 30.

[0050] Further, the placing plate 21 is further provided with a liquid absorbing cotton 26, the liquid absorbing cotton 26 is located at one side of the horizontal direction of the groove 211. In specific applications, before the mechanical arm throws away the needle cylinder 11 and the filter 12 after the filtration is completed, the liquid absorbing cotton 26 can be used to absorb the last drop of solution at the outlet of the needle cylinder 11 and the filter 12.

[0051] In some embodiments, the air feeding assembly 50 includes a pressing cylinder 51, a connecting plate 52, a pressure head 53 and a gas path control system, one end of the connecting plate 52 is connected with the output end of the pressing cylinder 51, the other end is connected with the pressure head 53, wherein the pressing cylinder 51 can move up and down and move by 90 degrees; the gas path control system is connected with a gas pressure and flow control system to meet the setting of different gas pressure and flow parameters in the filtration of samples, prevent the gas flow from being too large, make the samples that are easy to filter be quickly filtered, and the visual detection assembly cannot identify in time, and also prevent the gas flow from being too large to blow the filtered liquid dry.

[0052] Preferably, the bottom of the pressure head 53 connected with the needle cylinder 11 is a conical structure, wherein the pressure head 53 adopts bottom gas outlet and side or top gas inlet. Specifically, the bottom of the pressure head 53 is conical, and it can be understood that the pressure head 53 can be made of rubber material, or the outer wall of the pressure head 53 can be provided with a sealing layer made of rubber material, so as to realize sealing with the needle cylinder port and keep the internal pressure of the needle cylinder.

[0053] In some embodiments, the liquid receiving assembly 40 further comprises a rotating arm 42, one end of the rotating arm 42 is connected with a driving member, and the other end is provided with a waste liquid tank 43 for receiving waste liquid. Specifically, the driving member can be an electric motor, which is not shown in the figure. The electric motor drives the rotating arm 42 to rotate, so as to automatically move away after receiving the waste liquid.

[0054] Further, the bottom of the waste liquid tank 43 is provided with a flow guide pipeline 44 in communication with the waste liquid tank 43. Specifically, the flow guide pipeline 44 is a flow guide hole on the rotating arm 42. Before filtration, the waste liquid filtered by the filter assembly can be discharged through the flow guide pipeline 44, and it is not necessary to place a special liquid receiving container in the waste liquid tank 43, so as to improve the solution filtration efficiency.

[0055] The embodiment of the present application also provides a filtration method applied to the automatic needle type filtration device, and the filtration method comprises the following steps:

[0056] The mechanical arm places the needle cylinder 11 and the filter 12 pre-assembled together in the groove 211 on the placement plate 21; the waste liquid tank 43 on the rotating arm 42 is moved to below the filter 12;

[0057] Step 1: inject the rinsing liquid into the needle cylinder 11, the pressure head 53 of the gas feeding assembly 50 is connected with the needle cylinder 11 and feeds gas into the needle cylinder 11, and the liquid in the needle cylinder 11 flows to the filter under the action of the gas pressure, and then flows into the waste liquid tank 43 and flows out through the flow guide pipeline 44;

[0058] Step 2: after rinsing in the needle cylinder 11, the rotating arm 42 is moved away from below the filter 12, and the liquid receiving container 41 is moved to below the filter 12;

[0059] Step 3: inject the liquid to be filtered into the needle cylinder 11, the pressure head 53 of the gas feeding assembly 50 is connected with the needle cylinder 11 and drives the needle cylinder 11 and the filter 12 to move downward, so that the liquid outlet of the filter 12 extends into the liquid receiving container 41, feeds gas into the needle cylinder 11, and the liquid in the needle cylinder flows to the filter 12 under the action of the gas pressure, and then flows into the liquid receiving container after being filtered by the filter 12;

[0060] Step four: the visual detection component 30 monitors the liquid level in the syringe 11, and when the liquid level in the syringe 11 is monitored to be a preset threshold, the air feeding component 50 stops working, and the filtering is completed.

[0061] Further, the visual detection component 30 monitors the liquid level in the syringe 11 as follows:

[0062] S1: the light source 32 irradiates the syringe 11, the position of the camera 31 and the camera parameters are adjusted, and the position of the camera is relatively static with the position of the syringe 11; under the irradiation of the light source 32, the liquid level position in the syringe is clearly imaged in the camera 31;

[0063] S2: during filtering, as the liquid level in the syringe drops, the liquid level position in the syringe changes constantly, the camera captures images in real time, and the visual algorithm processes images in real time to calculate the liquid level;

[0064] S3: according to the calculated liquid level, a control signal is outputted, and when the liquid level drops to a preset value, it is determined that the filtering is completed, and an end signal is given.

[0065] It can be understood that the process of processing images by the visual algorithm includes:

[0066] Before any processing, some pre-processing is usually needed: including removing noise in the image, smoothing, enhancing contrast or adjusting color balance, etc.

[0067] Extracting the liquid level position features in the image for subsequent analysis and processing. This can be done by various algorithms, such as edge detection, corner detection, feature point extraction, etc.

[0068] According to the preset value of the liquid level, different algorithms can be used to analyze and process the extracted features, and the processing results and control signals are outputted.

[0069] Although the embodiments of the present application have been shown and described, it can be understood by those of ordinary skill in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the present application, and the scope of the present application is defined by the appended claims and their equivalent ranges.

Claims

1. An automatic needle filter device, characterized by, The application relates to a filter device and a filter method. The filter device comprises a filter assembly, a support assembly and a visual detection assembly. The filter assembly comprises a needle cylinder and a filter matched with the needle cylinder. The support assembly is used for placing the filter assembly and comprises a placing plate and a support column arranged at the corners of the placing plate. The placing plate is provided with a groove for placing the filter, and the bottom of the groove is provided with a through hole. The visual detection assembly is arranged on one side of the needle cylinder in the horizontal direction and is used for detecting the liquid level in the needle cylinder.

2. The automatic needle filter device of claim 1, wherein, The liquid receiving assembly comprises a liquid receiving container which is arranged below the filter.

3. The automatic needle filter device of claim 1, wherein, The air feeding assembly is connected with the needle cylinder and is used for changing the air pressure of the needle cylinder to control the flow rate of the liquid in the needle cylinder.

4. The automatic needle filter device of claim 3, wherein, The visual detection assembly is electrically connected with the air feeding assembly, and when the liquid level reaches a preset threshold, the air feeding assembly is controlled to stop feeding air.

5. The automatic needle filter device of claim 4, wherein, When the air feeding assembly moves downward, the filter assembly as a whole moves downward, so that the liquid outlet of the filter extends into the liquid receiving container.

6. An automatic needle filter device as claimed in claim 1, characterized in that The visual detection assembly comprises a camera and a light source.

7. The automatic needle filter device of claim 6, wherein The light source irradiates the needle cylinder, and the liquid surface in the needle cylinder is imaged in the camera.

8. The automatic needle filter device of claim 1, wherein, The liquid level in the needle cylinder is calculated according to the collected image to control the air feeding assembly to stop. The top of the support column is sleeved with a compression spring and a sliding ring.

9. A filtration method for use in the automatic needle filter device according to any one of claims 1-8, characterized in that, The sliding ring is arranged at the top of the compression spring, and the placing plate is connected with the sliding ring. The placing plate is further provided with an air claw which is arranged in cooperation with the needle cylinder to limit the movement of the needle cylinder. The air claw partially surrounds the needle cylinder. The placing plate is further provided with liquid absorbing cotton which is arranged on one side of the groove in the horizontal direction. The air feeding assembly comprises a compression air cylinder, a connecting plate, a pressure head and an air path control system. One end of the connecting plate is connected with the output end of the compression air cylinder, and the other end is connected with the pressure head. The compression air cylinder can move up and down and rotate by 90 degrees. The air path control system is connected with an air pressure and flow control system to meet different air pressure and flow parameters in sample filtration. The bottom of the pressure head connected with the needle cylinder is a conical structure. The pressure head adopts bottom air outlet and side or top air inlet. The liquid receiving assembly further comprises a rotating arm. One end of the rotating arm is connected with a driving member, and the other end is provided with a waste liquid tank for receiving waste liquid. The bottom of the waste liquid tank is provided with a flow guide pipeline which is communicated with the waste liquid tank. The filter method comprises the following steps. A mechanical hand places the needle cylinder and the filter which are assembled in advance into the groove on the placing plate. A waste liquid tank on a rotating arm is moved below the filter. Rinse liquid is injected into the needle cylinder. The pressure head of the air feeding assembly is connected with the needle cylinder and feeds air into the needle cylinder. The liquid in the needle cylinder flows to the filter under the action of air pressure and then flows into the waste liquid tank and flows out through the flow guide pipeline. After the needle cylinder is rinsed, the rotating arm is moved away from below the filter, and the liquid receiving container is moved below the filter. The liquid to be filtered is injected into the syringe. The pressure head of the air delivery component is connected to the syringe and drives the syringe and the filter to move downward until the liquid outlet of the filter extends into the liquid receiving container. Air is delivered into the syringe. The liquid in the syringe flows to the filter under the action of air pressure and then flows into the liquid receiving container. The visual detection component monitors the liquid level in the syringe. When the liquid level in the syringe is detected to be at a preset threshold, the visual detection component controls the air delivery component to stop working, thus completing the filtration.

10. The filtration method of claim 9, wherein, The steps for the vision detection component to monitor the liquid level in the syringe are as follows: A light source illuminates the syringe, the camera position and parameters are adjusted, and the position of the camera is made relatively stationary with respect to the position of the syringe; under the illumination of the light source, the position of the liquid level in the syringe is clearly imaged in the camera. During filtration, as the liquid level in the syringe drops, the position of the liquid level inside the syringe changes continuously. The camera captures images in real time, and the visual algorithm processes the images in real time to calculate the liquid level height. The output control signal is based on the calculated liquid level height. When the liquid level drops to the preset value, the filtration is determined to be complete, and an end signal is given.

Images