Blood coagulation analyzer and liquid level detection circuit thereof

Abstract

The utility model provides a blood coagulation analyzer and a liquid level detection circuit thereof. The circuit comprises a sampling unit and a detection unit, the sampling unit comprises an induction metal piece, and the induction metal piece is arranged on the outer surface of a detected object of the blood coagulation analyzer, is connected with the capacitance value sampling end of the detection unit and outputs a liquid level induction capacitance value; the detection unit comprises a detection chip and a threshold capacitor and is used for outputting a liquid level detection signal according to the size relation between the capacitance value of the threshold capacitor and the liquid level induction capacitance value; wherein the liquid level sensing capacitance value is larger than the capacitance value of the threshold value capacitor, the liquid level detection signal is a high level, the liquid level sensing capacitance value is smaller than the capacitance value of the threshold value capacitor, and the liquid level detection signal is a low level. The liquid height can be detected outside the liquid, direct contact with the liquid is avoided, and the problems that in an existing detection mode, cost is high, usability is not high, and the implementation mode is complex are solved.

Description

Technical Field

[0001] The present application relates to the technical field of detection circuits, and in particular to a coagulation analyzer and a liquid level detection circuit thereof. Background Art

[0002] Most of the existing coagulation analyzers use gravity sensors for liquid level detection. For example, float (steel reed switch) detection requires the float to be placed in the liquid. Long-term immersion can easily cause biological and chemical changes in the float, and it is not easy to replace the liquid in the barrel.

[0003] The advantages of ultrasonic detection, photoelectric (laser) detection, and radar detection are long-distance detection, but they are relatively costly and difficult to implement. Using sensor weighing to detect for a long time will cause sensor fatigue and induction failure, so they are not suitable for liquid level detection of coagulation analyzers. Utility Model Content

[0004] In this regard, the present application provides a coagulation analyzer and a liquid level detection circuit thereof, which detects the liquid level of the object being measured of the coagulation analyzer through low-cost, high-usability non-contact liquid level sensing, thereby solving the problems of high cost, poor usability, and complex implementation methods existing in existing detection methods.

[0005] To achieve the above objectives, the present application provides the following technical solutions:

[0006] The first aspect of the present application discloses a liquid level detection circuit of a coagulation analyzer, comprising: a sampling unit and a detection unit;

[0007] The sampling unit includes a sensing metal piece, which is placed on the outer surface of the object to be measured in the coagulation analyzer and connected to the capacitance sampling end of the detection unit to output the liquid level sensing capacitance value;

[0008] The detection unit includes a detection chip and a threshold capacitor, and is used to output a liquid level detection signal according to the size relationship between the capacitance of the threshold capacitor and the capacitance of the liquid level sensing;

[0009] Among them, when the liquid level sensing capacitance is greater than the capacitance of the threshold capacitance, the liquid level detection signal is at a high level; when the liquid level sensing capacitance is less than the capacitance of the threshold capacitance, the liquid level detection signal is at a low level.

[0010] Optionally, the liquid level detection circuit of the above-mentioned coagulation analyzer further includes: a display unit, the input end of the display unit is connected to the output end of the detection unit, and is used to display the relationship between the capacitance of the threshold capacitor represented by the liquid level detection signal and the liquid level sensing capacitance.

[0011] Optionally, in the above-mentioned liquid level detection circuit of the coagulation analyzer, the display unit comprises: a first resistor and a light emitting diode;

[0012] One end of the first resistor serves as an input end of the display unit, the other end of the first resistor is connected to the anode of the light emitting diode, and the other end of the light emitting diode is grounded.

[0013] Optionally, the liquid level detection circuit of the above-mentioned coagulation analyzer further includes: a pull-up unit, the input end of the pull-up unit is connected to the output end of the detection unit, for improving the anti-interference degree and load capacity of the liquid level detection signal.

[0014] Optionally, in the liquid level detection circuit of the above-mentioned coagulation analyzer, the pull-up unit includes: a second resistor, one end of the second resistor serves as an input end of the pull-up unit, and the other end of the second resistor is connected to a pull-up power supply.

[0015] Optionally, in the liquid level detection circuit of the above-mentioned coagulation analyzer, the detection unit comprises: the detection chip, the threshold capacitor and the first capacitor;

[0016] The Vdd pin of the detection chip is connected to one end of the first capacitor, and the connection point is connected to a pull-up power supply; the Vss pin of the detection chip is connected to the other end of the first capacitor, and the connection point is grounded;

[0017] The Cref pin of the detection chip is connected to one end of the threshold capacitor, and the other end of the threshold capacitor is grounded;

[0018] The Cin pin of the detection chip serves as a capacitance sampling terminal of the detection unit, and the OUT pin of the detection chip serves as an output terminal of the detection unit.

[0019] Optionally, in the liquid level detection circuit of the above-mentioned coagulation analyzer, the detection unit further includes:

[0020] A third resistor R1, one end of the third resistor R1 is connected to the Cin pin of the detection chip, and the other end of the third resistor R1 serves as a capacitance sampling end of the detection unit.

[0021] Optionally, in the liquid level detection circuit of the above-mentioned coagulation analyzer, the detection unit further includes:

[0022] A second capacitor, one end of the second capacitor is connected to the C pin of the detection chip, and the other end of the second capacitor is grounded.

[0023] The second aspect of the present application discloses a coagulation analyzer, comprising: a waste liquid barrel and / or a cleaning liquid barrel, the outer surface of the waste liquid barrel and / or the outer surface of the cleaning liquid barrel is provided with a liquid level detection circuit of the coagulation analyzer as described in any one of the items disclosed in the first aspect.

[0024] Optionally, in the above-mentioned coagulation analyzer, the cleaning liquid barrel and the waste liquid barrel are made of non-metallic material.

[0025] The liquid level detection circuit of the coagulation analyzer provided in the present application includes: a sampling unit and a detection unit; the sampling unit includes a sensing metal piece, the sensing metal piece is placed on the outer surface of the object to be measured of the coagulation analyzer, and is connected to the capacitance sampling end of the detection unit to output the liquid level sensing capacitance; the detection unit includes a detection chip and a threshold capacitor, which is used to output a liquid level detection signal according to the size relationship between the capacitance of the threshold capacitor and the liquid level sensing capacitance; wherein, when the liquid level sensing capacitance is greater than the capacitance of the threshold capacitor, the liquid level detection signal is a high level, and when the liquid level sensing capacitance is less than the capacitance of the threshold capacitor, the liquid level detection signal is a low level. The present application forms a simple circuit with a dedicated chip and forms an efficient and easy-to-use detection system with an external metal block, which can detect the height of the liquid outside the liquid and avoid direct contact with the liquid, that is, the liquid level of the object to be measured of the coagulation analyzer is detected by low-cost, high-usability non-contact liquid level sensing, which solves the problems of high cost, poor usability, and complex implementation methods in existing detection methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0027] Figure 1 A schematic diagram of the structure of a liquid level detection circuit of a coagulation analyzer provided in an embodiment of the present application;

[0028] Figures 2 to 4 Circuit diagrams of liquid level detection circuits of three coagulation analyzers provided in embodiments of the present application;

[0029] Figure 5 A schematic diagram of the structure of a liquid level detection circuit of a coagulation analyzer provided in another embodiment of the present application;

[0030] Figure 6 A circuit diagram of a liquid level detection circuit of a coagulation analyzer provided in another embodiment of the present application;

[0031] Figure 7A schematic diagram of the structure of a liquid level detection circuit of a coagulation analyzer provided in another embodiment of the present application;

[0032] Figure 8 A circuit diagram of a liquid level detection circuit of a coagulation analyzer provided in another embodiment of the present application. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0034] First of all, it should be explained that the coagulation analyzer is a medical clinical testing or analysis equipment (testing medical device). It is clinically used to measure the content of coagulation-related components in human blood, quantitatively or qualitatively analyze biochemical results, and provide reliable data basis for clinical diagnosis of patients. It is a routine testing equipment necessary for clinical use.

[0035] The detection indexes of hemostasis and thrombosis molecular markers of the fully automatic coagulation analyzer are closely related to various clinical diseases, such as atherosclerosis, diabetes, carotid artery thrombosis, etc. At the same time, patients who need surgery must also use a coagulation analyzer for testing to avoid heavy bleeding during the operation.

[0036] During the operation of the coagulation analyzer, the cleaning liquid and the waste liquid after cleaning are placed in a barrel. It is necessary to detect the liquid height in the barrel in real time to prevent the liquid in the waste liquid barrel from overflowing and the cleaning liquid in the cleaning liquid barrel from drying up. In this working environment, how to detect the liquid level in the barrel is an urgent problem to be solved.

[0037] The inventor has found that most of the current liquid level detection of coagulation analyzers uses gravity sensors. For example, the float (steel reed switch) switch detection requires the float to be placed inside the liquid. Long-term immersion can easily cause biological and chemical changes in the float, and it is not easy to replace the liquid in the barrel. The advantages of ultrasonic detection, photoelectric (laser) detection, and radar detection are long-distance detection, high cost, and difficult to implement. The use of sensor weighing for detection over a long period of time will cause sensor fatigue and induction failure, and they are not suitable for liquid level detection of coagulation analyzers.

[0038] In this regard, the present application provides a coagulation analyzer and a liquid level detection circuit thereof, which detects the liquid level of the object being measured of the coagulation analyzer through low-cost, high-usability non-contact liquid level sensing, thereby solving the problems of high cost, poor usability, and complex implementation methods existing in existing detection methods.

[0039] See also Figure 1 , the liquid level detection circuit of the coagulation analyzer mainly includes: a sampling unit 101 and a detection unit 102;

[0040] The sampling unit 101 includes a sensing metal piece, which is placed on the outer surface of the object to be measured of the coagulation analyzer and connected to the capacitance sampling end of the detection unit 102 to output the liquid level sensing capacitance value.

[0041] In actual applications, by placing the sensing metal piece on the outer surface of the object being measured of the coagulation analyzer and connecting the sensing metal piece to the capacitance sampling end of the detection unit 102, when the liquid level of the object being measured of the coagulation analyzer is higher or lower than the sensing metal piece, the liquid level sensing capacitance value will change.

[0042] Among them, the object to be measured can be a waste liquid bucket in a coagulation analyzer, or a cleaning liquid bucket in a coagulation analyzer; of course, it is not limited to this, and can also be determined according to the application environment and user needs, all within the protection scope of this application.

[0043] It should be noted that, in order to ensure the detection accuracy, the sensing metal piece and the lead of the connection detection unit 102 generally have a fixed capacitance. It can be understood that the sensed liquid in this application can be understood as the medium in a capacitor, and the metal piece and the lead can be understood as one pole of the capacitor. If the lead is a non-shielded wire and moves frequently, it may affect the distributed capacitance and the detection result. Therefore, the sensing metal piece and the lead of the connection detection unit 102 in this application are fixed.

[0044] Specifically, the sensing metal part can be directly connected to the capacitance sampling end of the detection unit 102, or it can be connected through a lead such as a radio frequency line, depending on the application environment and user needs, and is within the protection scope of this application.

[0045] It should also be noted that the sensing metal piece can be made practically according to the shape and size of the container of the object to be measured, so that the sensing metal piece can fit the container as well as possible to ensure the sensing sensitivity.

[0046] Combination Figure 2 The detection unit 102 includes a detection chip U1 and a threshold capacitor Cref, and is used to output a liquid level detection signal according to the relationship between the capacitance of the threshold capacitor Cref and the capacitance of the liquid level sensing capacitor.

[0047] Among them, the liquid level sensing capacitance is greater than the capacitance of the threshold capacitor Cref, and the liquid level detection signal is a high level; the liquid level sensing capacitance is less than the capacitance of the threshold capacitor Cref, and the liquid level detection signal is a low level.

[0048] In actual applications, the peripheral circuit of the detection chip U1 is welded with a fixed threshold capacitor Cref. The detection chip U1 compares the liquid level sensing capacitance with the capacitance of the threshold capacitor Cref. If the liquid level sensing capacitance is greater than or less than the capacitance of the threshold capacitor Cref, the detection chip U1 will change the electrical signal output, thereby detecting the liquid level status.

[0049] In some embodiments, see also Figure 2 , the detection unit 102 may include: a detection chip U1, a threshold capacitor Cref and a first capacitor C2.

[0050] Among them, the Vdd pin of the detection chip U1 is connected to one end of the first capacitor C2, and the connection point is connected to the pull-up power supply; the Vss pin of the detection chip U1 is connected to the other end of the first capacitor C2, and the connection point is grounded; the Cref pin of the detection chip U1 is connected to one end of the threshold capacitor Cref, and the other end of the threshold capacitor Cref is grounded; the Cin pin of the detection chip U1 serves as the capacitance sampling end of the detection unit 102, connected to the output end of the sampling unit 101; the OUT pin of the detection chip U1 serves as the output end of the detection unit 102, and outputs a liquid level detection signal.

[0051] In practical applications, the specific model of the detection chip U1 can be determined according to the application environment and user needs, such as HL2205, etc. Regardless of the specific model of the detection chip U1, it is within the protection scope of this application.

[0052] It should be noted that the specific capacitance of the threshold capacitor Cref can be adjusted according to the required liquid level state. It is generally a reference capacitor that matches the detection capacitor, and its value is generally 10P~20P. Of course, it can also be determined according to the application environment and user needs, all within the protection scope of this application.

[0053] In practical applications, the first capacitor C2 is a bypass capacitor of the detection chip U1, that is, a decoupling capacitor, which is used to ensure stable operation of the circuit. Specifically, the first capacitor C2 can be a 104P ceramic capacitor. Of course, it can also be determined according to the application environment and user needs, all within the protection scope of this application.

[0054] It should be noted that the pull-up power supply is used to ensure that the voltage output by the circuit can meet the direct access of most MCU I / Os. In practice, the pull-up power supply can be connected to a 5V power supply, of course, it can also be a 3V to 10V power supply, depending on the application environment and user needs.

[0055] In some embodiments, Figure 3As shown, the detection unit 102 may further include: a third resistor R1, one end of the third resistor R1 is connected to the Cin pin of the detection chip U1, and the other end of the third resistor R1 serves as a capacitance sampling end of the detection unit 102 and is connected to the output end of the sampling unit 101.

[0056] In practical applications, the third resistor R1 is connected to the Cin pin of the detection chip U1 to further improve the anti-interference ability of the liquid level detection circuit of the coagulation analyzer. In the liquid level detection circuit of the coagulation analyzer, the third resistor R1 is an important passive component in suppressing electromagnetic interference.

[0057] Specifically, the specific value of the third resistor R1 can be 1KΩ to 10KΩ. Of course, it is not limited thereto and can be determined according to the application environment and user needs, all within the protection scope of the present application.

[0058] It should be noted that, when the liquid level detection circuit of the coagulation analyzer is not greatly disturbed, the third resistor R1 can be short-circuited, that is, the Cin pin of the detection chip U1 directly receives the liquid level sensing capacitance output by the sampling unit 101 .

[0059] In some embodiments, Figure 4 As shown, the detection unit 102 may further include: a second capacitor C1, one end of the second capacitor C1 is connected to the C pin of the detection chip U1, and the other end of the second capacitor C1 is grounded.

[0060] In practical applications, the liquid level detection circuit of the coagulation analyzer with the second capacitor C1 can further improve its anti-interference ability. The value of the second capacitor C1 can be 100P to 104P, of course, it is not limited to this, and can also be determined according to the application environment and user needs, all within the protection scope of this application.

[0061] Similar to the third resistor R1 , when the liquid level detection circuit of the coagulation analyzer is not greatly disturbed, the C pin of the detection chip U1 can be left floating.

[0062] Based on the above principle, the liquid level detection circuit of the coagulation analyzer provided in this embodiment includes: a sampling unit 101 and a detection unit 102; the sampling unit 101 includes a sensing metal piece, which is placed on the outer surface of the object to be measured of the coagulation analyzer and is connected to the capacitance sampling end of the detection unit 102 to output the liquid level sensing capacitance; the detection unit 102 includes a detection chip U1 and a threshold capacitor Cref, which is used to output a liquid level detection signal according to the size relationship between the capacitance of the threshold capacitor Cref and the liquid level sensing capacitance; wherein, when the liquid level sensing capacitance is greater than the capacitance of the threshold capacitor Cref, the liquid level detection signal is a high level, and when the liquid level sensing capacitance is less than the capacitance of the threshold capacitor Cref, the liquid level detection signal is a low level. The present application forms a simple circuit with a dedicated chip and forms an efficient and easy-to-use detection system with an external metal block, which can detect the height of the liquid outside the liquid and avoid direct contact with the liquid, that is, the liquid level of the object to be measured of the coagulation analyzer is detected by low-cost, high-usability non-contact liquid level sensing, which solves the problems of high cost, poor usability, and complex implementation methods in the existing detection methods.

[0063] It is worth noting that, due to the characteristics of easy installation and adjustment of the sensing metal part, the liquid level detection circuit of the coagulation analyzer provided in the present application is easier to implement; in addition, the sensitivity of the detection circuit can be changed by adjusting the capacitance of the sensing metal part and the threshold capacitor Cref, so that the liquid level detection circuit of the coagulation analyzer can be suitable for different detection environments.

[0064] Based on the liquid level detection circuit of the coagulation analyzer provided in the above embodiment, optionally, as Figure 5 As shown, the liquid level detection circuit of the coagulation analyzer provided in another embodiment of the present application may also include: a display unit 103, wherein the input end of the display unit 103 is connected to the output end of the detection unit 102, and is used to display the relationship between the capacitance of the threshold capacitor Cref represented by the liquid level detection signal and the liquid level sensing capacitance.

[0065] In some embodiments, Figure 6 As shown, the display unit 103 may include: a first resistor R2 and a light emitting diode led1; one end of the first resistor R2 serves as the input end of the display unit 103, the other end of the first resistor R2 is connected to the anode of the light emitting diode led1, and the other end of the light emitting diode led1 is grounded.

[0066] In practical applications, the first resistor R2 is a current limiting resistor of the light emitting diode led1 to ensure that the light emitting diode led1 does not have overcurrent.

[0067] It should be noted that the light emitting diode led1 is used to facilitate observation of the relationship between the capacitance of the threshold capacitor Cref represented by the liquid level detection signal and the liquid level sensing capacitance. When the liquid level sensing capacitance is greater than the capacitance of the threshold capacitor Cref, the light emitting diode led1 is on; otherwise, the light emitting diode led1 is off.

[0068] In this embodiment, a display unit 103 can be added to the liquid level detection circuit of the coagulation analyzer. The light emitting diode LED1 displays the relationship between the capacitance of the threshold capacitor Cref represented by the level detection signal and the liquid level sensing capacitance, so that the liquid level status of the liquid level detection circuit of the coagulation analyzer can be observed more intuitively.

[0069] Based on the liquid level detection circuit of the coagulation analyzer provided in the above embodiment, optionally, as Figure 7 As shown, the liquid level detection circuit of the coagulation analyzer provided in another embodiment of the present application may further include: a pull-up unit 104, the input end of the pull-up unit 104 is connected to the output end of the detection unit 102, for improving the anti-interference degree and load capacity of the liquid level detection signal.

[0070] In some embodiments, Figure 8 As shown, the pull-up unit 104 includes: a second resistor R3, one end of the second resistor R3 serves as an input end of the pull-up unit 104, and the other end of the second resistor R3 is connected to a pull-up power supply.

[0071] In practical applications, the purpose of connecting the second resistor R3 to the liquid level detection circuit of the coagulation analyzer is to improve the anti-interference degree and enhance the output load capacity, and it can be removed in an environment where the interference is not serious.

[0072] It should be noted that the relevant description about the pull-up power supply can be found in the above embodiment and will not be repeated here.

[0073] Optionally, another embodiment of the present application further provides a coagulation analyzer, which may include: a waste liquid barrel and / or a cleaning liquid barrel, the outer surface of the waste liquid barrel, and / or the outer surface of the cleaning liquid barrel is provided with a liquid level detection circuit of the coagulation analyzer as described in any of the above embodiments.

[0074] In actual applications, the materials of the cleaning liquid barrel and the waste liquid barrel are generally non-metallic materials, such as glass, plastic, etc., which can be determined according to the application environment and user needs, and are all within the protection scope of this application.

[0075] In some embodiments, the coagulation analyzer may be a fully automatic coagulation analyzer, but is not limited thereto and may also be other existing coagulation analyzers, all of which are within the protection scope of the present application.

[0076] The coagulation analysis provided in this embodiment is provided with a liquid level detection circuit of the coagulation analyzer as described in any of the above embodiments on the outer surface of the waste liquid barrel and / or the cleaning liquid barrel. The liquid level status of the corresponding liquid barrel can be detected by the liquid level detection circuit. Compared with the existing detection method, the liquid level detection circuit has the advantages of low cost, high ease of use, and non-contact, which solves the problems of high cost, poor ease of use, and complex implementation methods existing in the existing detection methods.

[0077] It should be noted that, for the relevant description of the liquid level detection circuit of the coagulation analyzer, reference may be made to the above embodiments, which will not be repeated here; for the coagulation analyzer, reference may also be made to the prior art, which will not be repeated in this application.

[0078] The features recorded in the various embodiments in this specification can be replaced or combined with each other, and the same and similar parts between the various embodiments can refer to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. The system and system embodiments described above are only schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative work.

[0079] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0080] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

[0081] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

Claims

1. A liquid level detection circuit for a coagulation analyzer, characterized in that: include: Sampling unit and detection unit; The sampling unit includes a sensing metal piece, which is placed on the outer surface of the object to be measured in the coagulation analyzer and connected to the capacitance sampling end of the detection unit to output the liquid level sensing capacitance value; The detection unit includes a detection chip and a threshold capacitor, and is used to output a liquid level detection signal according to the size relationship between the capacitance of the threshold capacitor and the capacitance of the liquid level sensing; Among them, when the liquid level sensing capacitance is greater than the capacitance of the threshold capacitance, the liquid level detection signal is at a high level; when the liquid level sensing capacitance is less than the capacitance of the threshold capacitance, the liquid level detection signal is at a low level.

2. The liquid level detection circuit of the coagulation analyzer according to claim 1, characterized in that: Also includes: A display unit, wherein the input end of the display unit is connected to the output end of the detection unit, and is used to display the relationship between the capacitance of the threshold capacitor represented by the liquid level detection signal and the liquid level sensing capacitance.

3. The liquid level detection circuit of the coagulation analyzer according to claim 2, characterized in that: The display unit comprises: a first resistor and a light emitting diode; One end of the first resistor serves as an input end of the display unit, the other end of the first resistor is connected to the anode of the light emitting diode, and the other end of the light emitting diode is grounded.

4. The liquid level detection circuit of the coagulation analyzer according to claim 1, characterized in that: Also includes: A pull-up unit, the input end of which is connected to the output end of the detection unit, is used to improve the anti-interference degree and load capacity of the liquid level detection signal.

5. The liquid level detection circuit of the coagulation analyzer according to claim 4, characterized in that: The pull-up unit comprises: a second resistor, one end of the second resistor serves as an input end of the pull-up unit, and the other end of the second resistor is connected to a pull-up power supply.

6. The liquid level detection circuit of the coagulation analyzer according to claim 1, characterized in that: The detection unit comprises: the detection chip, the threshold capacitor and a first capacitor; The Vdd pin of the detection chip is connected to one end of the first capacitor, and the connection point is connected to a pull-up power supply; the Vss pin of the detection chip is connected to the other end of the first capacitor, and the connection point is grounded; The Cref pin of the detection chip is connected to one end of the threshold capacitor, and the other end of the threshold capacitor is grounded; The Cin pin of the detection chip serves as a capacitance sampling terminal of the detection unit, and the OUT pin of the detection chip serves as an output terminal of the detection unit.

7. The liquid level detection circuit of the coagulation analyzer according to claim 6, characterized in that: The detection unit further includes: A third resistor R1, one end of the third resistor R1 is connected to the Cin pin of the detection chip, and the other end of the third resistor R1 serves as a capacitance sampling end of the detection unit.

8. The liquid level detection circuit of the coagulation analyzer according to claim 6, characterized in that: The detection unit further includes: A second capacitor, one end of the second capacitor is connected to the C pin of the detection chip, and the other end of the second capacitor is grounded.

9. A coagulation analyzer, characterized in that: include: A waste liquid barrel and / or a cleaning liquid barrel, wherein the outer surface of the waste liquid barrel and / or the outer surface of the cleaning liquid barrel is provided with a liquid level detection circuit of the coagulation analyzer according to any one of claims 1 to 8.

10. The blood coagulation analyzer according to claim 9, characterized in that: The cleaning liquid barrel and the waste liquid barrel are made of non-metallic materials.

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