Liquid level sensing device, method and method for lowering a sampling needle

Abstract

The application relates to a liquid surface sensing device, a method and a descending method of a sampling needle, wherein the liquid surface sensing device comprises a sample rack with a plurality of uniform slots capable of accommodating sample containers of various specifications; an image identifier is used to identify and distinguish different sample containers in an image recognition mode when the sample rack is in a sample suction area; a sample suction needle assembly comprises a sampling needle, a laser ranging device, a needle beam and a liquid surface detection device; one end of the needle beam is fixed with the sampling needle, the laser ranging device and the liquid surface detection device; and the liquid surface detection device can detect a liquid surface based on a capacitance detection method. The scheme can greatly improve detection stability and reduce a dead volume, so that the needle tip cannot touch the bottom of the container to cause needle puncture.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of medical devices, and is suitable for a chemiluminescence device, and relates to a liquid level sensing device and method and a downward method of a sampling needle. BACKGROUND

[0002] Currently, the sampling needle on a full-automatic chemiluminescence instrument generally detects samples based on a capacitive detection technology. However, due to environmental interference and reduced detection sensitivity when the liquid volume is small, the technology has certain liquid level false detection and missed detection in actual use, especially when the sample volume at the bottom of the container is small. SUMMARY

[0003] In order to further improve the stability of liquid level detection and reduce the detection dead volume, the present application proposes a liquid level sensing device and method based on container image recognition and laser ranging technology.

[0004] The technical scheme adopted by the present application to solve its technical problems is:

[0005] A liquid level sensing device based on container image recognition, comprising:

[0006] a sample holder having a plurality of uniform insertion slots capable of accommodating sample containers of multiple specifications;

[0007] an image recognizer configured to recognize and distinguish different sample containers by image recognition when the sample holder is in a sample suction area;

[0008] a sample needle assembly comprising a sampling needle, a laser ranging device, a needle beam, and a liquid level detection device; one end of the needle beam is fixed with the sampling needle, the laser ranging device, and the liquid level detection device; the liquid level detection device can detect the liquid level based on a capacitive detection method;

[0009] a database module configured to save the tube bottom height parameter of the sample container of multiple specifications installed on the sample holder and the functional relationship information between the container height parameter and the liquid volume, so as to be compared and matched by the image recognizer when obtaining the sample container image.

[0010] Preferably, the liquid level sensing device based on container image recognition of the present application comprises:

[0011] a main control chip, a ranging chip, a power supply interface, a serial communication interface, and a peripheral circuit;

[0012] the main control chip and the laser ranging device are connected through the serial communication interface to interact signals, the main control chip is connected with the control board of the sampling needle through the serial communication interface to interact signals, and the main control chip is connected with a power supply through the power supply interface.

[0013] Preferably, the liquid level sensing device based on container image recognition of the present application, the image recognizer further has a module for reading bar codes.

[0014] A liquid level sensing method based on container image recognition, comprising the following steps:

[0015] S1, placing sample containers on the sample rack, when the sample rack is pushed to the sample area, using an image recognizer to take pictures of the sample rack and sample containers and compare them, identifying the type of sample container placed at each position;

[0016] S2, retrieving information saved in the database module to obtain the tube bottom height parameter of each sample container and the functional relationship between the liquid level height parameter in the sample container and the liquid volume;

[0017] S3, moving the sample needle assembly above the sample container to be aspirated and staying for a short time, and obtaining the liquid level height parameter in the sample container below by a laser ranging device;

[0018] S4, converting the approximate liquid volume V0 in the container by the liquid level height parameter and combining the tube bottom height parameter.

[0019] Preferably, in step S4 of the liquid level sensing method based on container image recognition of the present application, the laser ranging device transmits the obtained liquid level height parameter to the main control chip through the serial communication interface, and then the main control chip retrieves the tube bottom height parameter of the sample container from the database module and combines the functional relationship between the liquid level height parameter in the corresponding sample container and the liquid volume to calculate the liquid volume V0 in the container.

[0020] A downward method of a sampling needle, using the above-mentioned liquid level sensing method based on container image recognition, after step S4, the following step is performed:

[0021] S5, judging the size range of V0;

[0022] When V0>500uL, control the sampling needle to move quickly to the sample container port first, and then switch to the normal speed liquid level detection mode M1 to detect and aspirate the sample;

[0023] When V0≤500uL, control the sampling needle to move quickly to the liquid level above 1mL first, and then switch to the slow liquid level detection mode M2, stop quickly after slow sensing the liquid level position, and then descend the corresponding distance according to the actual liquid aspiration volume requirement to ensure that there is no air suction;

[0024] S6, limiting the maximum downward distance of the sampling needle to be higher than the tube bottom height according to the tube bottom height parameter obtained in step S2.

[0025] Preferably, the down method of the sampling needle of the present application, after switching to the slow liquid level detection mode M2, stopping immediately after the slow sensing of the liquid level position, and according to the actual liquid suction volume demand, the liquid suction volume is V, then running to the corresponding height of V*120%, this step is only executed once before the first time of sample suction.

[0026] Preferably, the down method of the sampling needle of the present application, in the slow liquid level detection mode M2, the method of sensing the liquid level position is the liquid level detection method based on capacitive detection.

[0027] The beneficial effects of the present application are:

[0028] The scheme of the present application can greatly improve the detection stability and reduce the detection dead volume, so as to ensure that the needle tip will not touch the bottom of the container to cause the needle puncture phenomenon. BRIEF DESCRIPTION OF DRAWINGS

[0029] The technical scheme of the present application will be further described below in combination with the drawings and examples.

[0030] Figure 1 is the image recognition principle schematic diagram of the embodiment of the present application;

[0031] Figure 2 is the structure schematic diagram of the sample suction needle assembly of the embodiment of the present application;

[0032] Figure 3 is the circuit structure schematic diagram of the laser ranging device of the embodiment of the present application.

[0033] The reference signs in the drawings are:

[0034] 1 sample rack;

[0035] 2 image recognizer;

[0036] 3 sample suction needle assembly;

[0037] 11 slot;

[0038] 31 sampling needle;

[0039] 32 laser ranging device;

[0040] 33 needle beam;

[0041] 34 liquid level detection device;

[0042] A first container;

[0043] B second container;

[0044] C third container;

[0045] D fourth container. DETAILED DESCRIPTION

[0046] It should be noted that the embodiments and features in the embodiments in the present application can be combined with each other in the case of no conflict.

[0047] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the scope of protection of the present application. In addition, the terms "first", "second" and the like are only for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" and the like can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified and limited, the terms "mounting", "connecting", "connecting" should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication between two elements inside. For those skilled in the art, the specific meaning of the above terms in the present application can be understood through specific circumstances.

[0048] In the description of the present application, it should be noted that unless otherwise specified and limited, the terms "mounting", "connecting", "connecting" should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication between two elements inside. For those skilled in the art, the specific meaning of the above terms in the present application can be understood through specific circumstances.

[0049] The technical solutions of the present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0050] The present embodiment provides a liquid level sensing device based on container image recognition, as shown in Figure 1 , 2 as shown, comprising:

[0051] The sample holder 1 has a plurality of uniform slots 11 capable of accommodating sample containers of various specifications; the sample holder 1 used in the present embodiment can accommodate at least four kinds of sample containers, as shown in Figure 1 includes a first container A, a second container B, a third container C, and a fourth container D;

[0052] An image recognizer 2 is configured to recognize and distinguish different sample containers (in this embodiment, the first container A, the second container B, the third container C, and the fourth container D, which are very different in shape and are not easy to be misjudged, and if more types of containers are needed to be used, containers of similar shapes should also be avoided) by image recognition when the sample rack 1 is in the sample suction area.

[0053] A sample needle assembly 3 includes a sampling needle 31, a laser ranging device 32, a needle beam 33, and a liquid level detection device 34. One end of the needle beam 33 is fixed with the sampling needle 31, the laser ranging device 32, and the liquid level detection device 34. The liquid level detection device 34 can detect the liquid level based on the capacitive detection method.

[0054] A database module is configured to save the tube bottom height parameters of the sample containers of different specifications installed on the sample rack 1 (the shape of each slot 11 on the sample rack 1 is consistent, so the position of a specific sample container placed in the slot 11 is fixed, that is, the tube bottom height and other parameters are determined) and the functional relationship information between the liquid level height parameters and the liquid volume in the container (the cross-sectional areas of different containers are different, so the function of different containers is different; the functional relationship is relatively determined for each container, which can be obtained by actual measurement during the debugging of each instrument and is pre-stored in the software debugging parameters), so that the image recognizer 2 can compare and match when obtaining the image of the sample container.

[0055] Preferably, the liquid level sensing device based on container image recognition of this embodiment includes a laser ranging device 32, a liquid level detection device 34, and a sampling needle 31. Figure 3 As shown in the figure, the laser ranging device 32 includes:

[0056] A main control chip, a ranging chip, a power supply interface, a serial communication interface, and peripheral circuits.

[0057] The main control chip is connected with the laser ranging device 32 through the serial communication interface to interact signals, the main control chip is connected with the control board of the sampling needle 31 through the serial communication interface to interact signals, and the main control chip is connected with a power supply through the power supply interface.

[0058] Preferably, the liquid level sensing device based on container image recognition of this embodiment further includes a bar code reading module. If the sample container also has a bar code, the type information of the container can be directly obtained by scanning the code, thereby increasing the reliability of image recognition.

[0059] This embodiment provides a liquid level sensing method based on container image recognition, which includes the following steps:

[0060] S1, placing a sample container on the sample rack 1, when the sample rack 1 is pushed to the sample suction area, using the image recognizer 2 to take pictures of the sample rack 1 and the sample container for comparison, and identifying the type of the sample container placed at each position;

[0061] S2, retrieve the information stored in the database module to obtain the tube bottom height parameter of each sample container and the function relationship between the liquid level parameter and the liquid volume in the sample container;

[0062] S3, move the sample needle assembly 3 above the sample container to be sampled and stay for a short time, and obtain the liquid level parameter in the sample container below through the laser ranging device 32;

[0063] S4, calculate the approximate liquid volume V0 in the container by the liquid level parameter and the tube bottom height parameter.

[0064] Preferably, in step S4, the liquid level sensing method based on container image recognition of the embodiment transmits the obtained liquid level parameter to the main control chip through the serial communication interface, and then the main control chip retrieves the tube bottom height parameter of the sample container from the database module, and calculates the liquid volume V0 in the container by combining the function relationship between the liquid level parameter and the liquid volume in the corresponding sample container.

[0065] The embodiment provides a downward method of a sampling needle, which adopts the above-mentioned liquid level sensing method based on container image recognition, and executes the following step after step S4:

[0066] S5, judge the size range of V0;

[0067] When V0>500uL, control the sampling needle to first move quickly (v1) to the sample container port to save the downward time, and then switch to the normal speed (v2) liquid level detection mode M1 to detect and absorb the sample (when the liquid volume is greater than the value, the liquid level detection technology based on the capacitance detection can easily and reliably detect the liquid level and correctly sample) ;

[0068] When V0≤500uL, control the sampling needle to first move quickly to the position above the liquid level by 1mL to save the downward time, and then switch to the slow speed (v3) liquid level detection mode M2, and stop quickly after detecting the liquid level position, and then descend by a corresponding distance according to the actual liquid absorption volume requirement to ensure that there is no empty absorption (the downward distance should ensure that the sample flows over the needle tip by a certain distance to ensure that there is no empty absorption) ;

[0069] S6, limit the maximum downward distance of the sampling needle to be higher than the tube bottom height according to the tube bottom height parameter obtained in step S2, so that the needle tip cannot touch the container bottom to cause the needle puncture phenomenon.

[0070] The above-mentioned v3 <v2 <v1.

[0071] Preferably, the down method of the sampling needle of the embodiment, after switching to the slow liquid level detection mode M2, stopping immediately after the slow sensing of the liquid level position, and then according to the actual liquid suction volume demand, the sampling needle is lowered by a corresponding distance, and the liquid suction volume is V, then the corresponding height of V*120% is run down.

[0072] Preferably, the down method of the sampling needle of the embodiment, in the slow liquid level detection mode M2, the method for sensing the liquid level position is a liquid level detection method based on capacitive detection. The detection precision of the liquid level detection method based on capacitive detection is high, and it is a mature technology in the prior art, and is suitable for high-precision liquid level detection.

[0073] Based on the above ideal embodiments according to the present application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the present application. The technical scope of the present application is not limited to the content in the specification, and the technical scope must be determined according to the scope of claims.

Claims

1. A liquid level sensing device based on container image recognition, characterized by, The application relates to a liquid level sensing device based on container image recognition. The device can realize the following steps: first, the tube bottom height parameter and the liquid level height parameter are obtained, the tube bottom height parameter is combined to calculate the approximate liquid quantity V0 in the container, and the tube bottom height of each sample container is calculated; then, the size range of V0 is judged; when V0 is greater than 500 uL, the sampling needle is controlled to move to the sample container at a high speed (v1) first, then the liquid level detection mode M1 at a normal speed (v2) is switched to, the sample is detected and sucked; when V0 is less than or equal to 500 uL, the sampling needle is controlled to move to the position above 1 mL of the liquid level at a high speed (v1) first, then the liquid level detection mode M2 at a low speed (v3) is switched to, the liquid level position is sensed at the low speed, then the sampling needle is stopped suddenly, and then the sampling needle is lowered by a corresponding distance according to the actual liquid sucking quantity demand, so that the empty sucking phenomenon is avoided; wherein, v3 < v2 < v1; finally, the maximum lowering distance of the sampling needle is limited to be higher than the tube bottom height according to the obtained tube bottom height parameter. The laser ranging device (32) comprises a main control chip, a ranging chip, a power supply interface, a serial communication interface and peripheral circuits; the main control chip is connected with the laser ranging device (32) through the serial communication interface to realize signal interaction, the main control chip is connected with the control board of the sampling needle (31) through the serial communication interface to realize signal interaction, and the main control chip is connected with a power supply through the power supply interface. The image recognizer (2) further has a bar code reading module. The implementation relies on the liquid level sensing device based on container image recognition, and the steps before the tube bottom height parameter and the liquid level height parameter are obtained are as follows: S1, the sample container is placed on the sample rack (1), when the sample rack (1) is pushed to the sample sucking area, the image recognizer (2) is used to take pictures of the sample rack (1) and the sample container, and the type of the sample container placed at each position is recognized; 2. The liquid level sensing device based on container image recognition of claim 1, wherein, S2, the information stored in the database module is called to obtain the tube bottom height parameter of each sample container and the function relationship between the liquid level height parameter and the liquid quantity in the sample container.

3. The liquid level sensing device based on container image recognition of claim 1, wherein, ​ 4. A liquid level sensing method based on container image recognition, characterized by, ​ ​ ​ S3, the sample needle assembly (3) is moved to the sample container to be sucked, and is temporarily stopped, and the liquid level parameter in the sample container below is acquired by the laser ranging device (32).

5. The liquid level sensing method based on container image recognition according to claim 4, wherein, In step S4, the liquid level parameter acquired by the laser ranging device (32) is transmitted to the main control chip through a serial communication interface, and the main control chip calls the tube bottom height parameter of the sample container from a database module, and combines the function relationship between the liquid level parameter in the corresponding sample container and the liquid volume to calculate the liquid volume V0 in the container.

6. The method of claim 4, wherein, Switching to the slow liquid level detection mode M2, after the slow induction of the liquid level position and the emergency stop, the corresponding distance is lowered according to the actual liquid suction demand, and the liquid suction volume is V, and the corresponding height of V*120% is run downward.

7. The method of descending a sampling needle according to claim 6, wherein, In the slow liquid level detection mode M2, the method for sensing the liquid level position is a liquid level detection method based on capacitive detection.

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