Sample analyzer and liquid aspiration control method thereof

1 . A sample analyzer, comprising:

a liquid aspiration assembly for aspirating a liquid in a container;

a driving assembly for driving the liquid aspiration assembly to move; and

a signal acquisition and analysis assembly for acquiring an electrical signal based on a capacitance of the liquid aspiration assembly; wherein:

while the liquid aspiration assembly is driven by the driving assembly to move down toward the container;

the signal acquisition and analysis assembly acquires a first electrical signal and determines whether the first electrical signal meets a first preset condition, after an abrupt change occurs in the electrical signal;

in response to determining that the first electrical signal meets the first preset condition, the signal acquisition and analysis assembly acquires a second electrical signal and determines whether the second electrical signal meets a second preset condition different from the first preset condition;

in response to determining that the second electrical signal meets the second preset condition, the signal acquisition and analysis assembly sends liquid surface reaching information;

in response to determining that the second electrical signal does not meet the second preset condition, the signal acquisition and analysis assembly re-acquires a first electrical signal and determines whether the re-acquired first electrical signal meets the first preset condition; and

in response to determining that the re-acquired first electrical signal meets the first preset condition, the signal acquisition and analysis assembly sends the liquid surface reaching information.

2 . The sample analyzer according to claim 1 , wherein the signal acquisition and analysis assembly sends information indicating that the liquid aspiration assembly reaches a surface of the liquid at a preset time point in response to the re-acquired first electrical signal meeting the first preset condition, and the preset time point is no later than the latest time point of reporting the information indicating that the liquid aspiration assembly reaches a surface of the liquid.

3 . The sample analyzer according to claim 1 , wherein the signal acquisition and analysis assembly determines whether the first electrical signal and the second electrical signal do not meet the second preset condition.

4 . The sample analyzer according to claim 1 , wherein the signal acquisition and analysis assembly determines that the first electrical signal meets the first preset condition in response to the first electrical signal meeting a preset threshold.

5 . The sample analyzer according to claim 1 , wherein the signal acquisition and analysis assembly determines that the second electrical signal does not meet the second preset condition, in response to a signal characteristic of the second electrical signal being the same as at least one preset first abnormal signal characteristic, and determines that the second electrical signal meets the second preset condition, in response to the signal characteristic of the second electrical signal being different from the preset first abnormal signal characteristic.

6 . The sample analyzer according to claim 1 , wherein the signal acquisition and analysis assembly determines that the second electrical signal does not meet the second preset condition in response to the second electrical signal regressing to a preset range in a vicinity of a signal baseline.

7 . The sample analyzer according to claim 1 , wherein the signal acquisition and analysis assembly determines that the second electrical signal does not meet the second preset condition in response to a slope of a change trend of the second electrical signal being less than or equal to a preset slope threshold, or less than or equal to a slope of a change trend of the first electrical signal.

8 . The sample analyzer according to claim 1 , wherein the signal acquisition and analysis assembly is configured to determine that the second electrical signal meets the second preset condition, in response to the second electrical signal or the first electrical signal and the second electrical signal having a change rate between a slope of a signal change in a second time period and a slope of a signal change in a first time period that is greater than a preset threshold of change rate, wherein the second time period is later than the first time period.

9 . The sample analyzer according to claim 1 , wherein the signal acquisition and analysis assembly sends information indicating that the liquid aspiration assembly reaches a surface of the liquid at a preset time point that is no later than the latest time point of reporting the information indicating that the liquid aspiration assembly reaches a surface of the liquid.

10 . The sample analyzer according to claim 1 , wherein the signal acquisition and analysis assembly further acquires and analyze a third electrical signal after sending the liquid surface reaching information.

11 . The sample analyzer according to claim 10 , wherein the signal acquisition and analysis assembly acquires the electrical signal as the third electrical signal from at least one of the following time periods:

from sending information indicating that the liquid aspiration assembly reaches a surface of the liquid to the liquid aspiration assembly stopping moving down;

from the liquid aspiration assembly stopping moving down to the liquid aspiration assembly beginning to aspirate the liquid;

from the liquid aspiration assembly beginning to aspirate the liquid to the liquid aspiration assembly completing liquid aspiration; and

from the liquid aspiration assembly completing the liquid aspiration to the liquid aspiration assembly moving up.

12 . The sample analyzer according to claim 10 , wherein the signal acquisition and analysis assembly further determines, according to at least the third electrical signal, whether the third electrical signal meets a third preset condition, and outputs information for indicating abnormal liquid aspiration, in response to the third electrical signal meeting the third preset condition.

13 . The sample analyzer according to claim 12 , wherein the signal acquisition and analysis assembly determines whether the third electrical signal meets the third preset condition, according to the first electrical signal and/or the second electrical signal, and the third electrical signal.

14 . The sample analyzer according to claim 12 , wherein the third preset condition comprises one or more conditions, and the signal acquisition and analysis assembly outputs a warning in response to the third electrical signal meeting the third preset condition, the warning comprising at least one of following warning information:

first warning information for indicating that the container has static electricity, which causes the liquid aspiration abnormality;

second warning information for indicating that there is a liquid film adhering to an inner wall of the container, which causes the liquid aspiration abnormality;

third warning information for indicating that there is a bubble above the liquid in the container, which causes the liquid aspiration abnormality;

fourth warning information for indicating that the liquid aspiration assembly is in contact with a liquid droplet on an inner wall of the container, which causes the liquid aspiration abnormality; and

fifth warning information for indicating that the liquid in the container is insufficient, which causes the liquid aspiration abnormality.

15 . The sample analyzer according to claim 12 , wherein the signal acquisition and analysis assembly determines that the third electrical signal meets the third preset condition, in response to a signal characteristic of the third electrical signal being the same as a preset second abnormal signal characteristic.

16 . The sample analyzer according to claim 10 , wherein the signal acquisition and analysis assembly outputs a warning which indicates that the aspiration is abnormal, in response to the third electrical signal regressing to a preset range in a vicinity of a signal baseline.

17 . The sample analyzer according to claim 10 , wherein the signal acquisition and analysis assembly outputs a warning which indicates that the aspiration is abnormal, in response to the third electrical signal having a change rate between a slope in a fourth time period and a slope in a third time period that is greater than a preset threshold of change rate, wherein the fourth time period is later than the third time period.

18 . The sample analyzer according to claim 10 , wherein the signal acquisition and analysis assembly further outputs a warning which indicates that the aspiration is abnormal and/or the liquid in the container is insufficient, in response to a voltage amplitude of the third electrical signal from the completion of liquid aspiration of the liquid aspiration assembly to the upward movement of the liquid aspiration assembly being less than or equal to a preset amplitude threshold.

19 . The sample analyzer according to claim 1 , wherein a rate at which the signal acquisition and analysis assembly acquires the electrical signal is at least eight times higher than a rate of sudden change in capacitance in response to the liquid aspiration assembly contacting with the liquid surface.

20 . The sample analyzer according to claim 1 , wherein the sample analysis analyzer further comprises a control module that controls the movement of the driving assembly, so as to keep the liquid aspiration assembly from moving down, based on the information indicating that the liquid aspiration assembly reaches a surface of the liquid sent by the signal acquisition and analysis assembly.

21 . A liquid aspiration control method for a sample analyzer, comprising:

during a liquid aspiration assembly moving down in a container,

acquiring, by a signal acquisition assembly of the sample analyzer, a first electrical signal for indicating a capacitance change of the liquid aspiration assembly,

determining whether the first electrical signal meets a first preset condition;

acquiring, by the signal acquisition assembly, a second electrical signal for indicating the capacitance change of the liquid aspiration assembly, in response to the first electrical signal meeting the first preset condition,

wherein the signal acquisition assembly is configured to convert the capacitance change of the liquid aspiration assembly into an electrical signal, wherein the liquid aspiration assembly for aspirating a liquid in the container is electrically connected to the signal acquisition assembly;

determining whether the second electrical signal meets a second preset condition different from the first preset condition; and

sending liquid surface reaching information in response to determining that the second electrical signal meets the second preset condition; and

in response to determining that the second electrical signal does not meet the second preset condition, re-acquiring, by the signal acquisition assembly, a first electrical signal and determining whether the re-acquired first electrical signal meets the first preset condition; and

in response to determining that the re-acquired first electrical signal meets the first preset condition, sending the liquid surface reaching information.

22 . The liquid aspiration control method according to claim 21 , wherein the liquid aspiration control method further comprises:

acquiring a third electrical signal by the signal acquisition assembly after sending the liquid surface reaching information;

at least determining whether the third electrical signal meets a third preset condition; and

outputting a warning which indicates that the aspirating is abnormal in response to the electrical signal meeting the third preset condition.

23 . The liquid aspiration control method according to claim 22 , wherein at least determining whether the third electrical signal meets a third preset condition comprises:

determining that the third electrical signal meets the third preset condition in response to a signal characteristic of the third electrical signal being the same as a preset abnormal signal characteristic.