Automated analyzing device and method for determining water leakage from same

Abstract

The objective of the present invention is to provide an automated analyzing device with which it is possible to determine water leakage even without adding a new component or control pattern for the same. To this end, an automated analysis device according to the present invention comprises: a dispensing nozzle for dispensing a specimen or a reagent; a pressure generation source for generating pressure within the dispensing nozzle; a flow passage providing communication between the pressure generation source and the dispensing nozzle; a pressure sensor for detecting the pressure in the flow passage; a solenoid valve provided in the flow passage to open and close the flow passage; and a control unit for determining the presence or absence of water leakage on the basis of a change in pressure data accompanying suction or ejection of air by the dispensing nozzle.

Description

Automatic analyzer and method for determining water leakage

[0001] The present invention relates to an automatic analyzer and a method for determining water leakage therefrom.

[0002] The dispensing mechanism of an automated analyzer for quantitative and qualitative analysis of blood, urine, etc., includes a solenoid valve for adjusting the pressure of a dispensing syringe when aspirating or dispensing a sample or reagent, and a pressure sensor for detecting the pressure in the dispensing flow path. If foreign matter gets into the solenoid valve or the dispensing flow path deteriorates over time, leakage from the dispensing mechanism may occur due to malfunction of the solenoid valve or poor flow path condition. Therefore, an automated analyzer with a function for determining whether or not there is leakage from the dispensing mechanism has been proposed. For example, Patent Document 1 discloses a system that includes a pressure sensor in the flow path and at least two solenoid valves installed on either side of the pressure sensor. The pressure sensors are used to acquire pressure waveform data with each solenoid valve closed, and the acquired data is compared with normal data to determine leakage from the flow path.

[0003] Japanese Patent Application Laid-Open No. 2020-16449

[0004] However, the technique described in Patent Document 1 has the problem that not only does it require the addition of new components such as solenoid valves, but it also requires the addition of control patterns for these components.

[0005] An object of the present invention is to provide an automatic analyzer that can detect water leakage without adding new components or control patterns.

[0006] In order to solve the above-mentioned problems, the automatic analyzer of the present invention comprises a dispensing nozzle that dispenses a sample or reagent, a pressure generating source that generates pressure within the dispensing nozzle, a flow path that connects the pressure generating source to the dispensing nozzle, a pressure sensor that detects the pressure within the flow path, an electromagnetic valve that is provided in the flow path and opens and closes the flow path, and a control unit that determines whether or not there is a leak based on changes in pressure data associated with the suction or discharge of air by the dispensing nozzle.

[0007] According to the present invention, it is possible to provide an automatic analyzer that can detect water leakage without adding new components or control patterns.

[0008] 1 is a schematic diagram of an automatic analyzer; FIG. 2 is a schematic diagram showing the configuration of a dispensing mechanism; FIG. 3 is a block diagram of a configuration related to a water leak detection process using pressure data detected by a pressure sensor; FIG. 4 is a graph of a pressure waveform acquired by a feature extraction unit when a dispensing nozzle aspirates and discharges air (the solid line is an example of an abnormal state where there is water leakage due to a faulty solenoid valve, and the dotted line is an example of a normal state where there is no water leakage); FIG. 5 is a graph of a vibration frequency distribution acquired by a feature extraction unit when a dispensing nozzle aspirates and discharges air (the solid line is an example of an abnormal state where there is water leakage due to a faulty solenoid valve, and the dotted line is an example of a normal state where there is no water leakage); and FIG. 6 is a flowchart showing the operation of an automatic analyzer when detecting a water leak in Example 1; and FIG. 7 is a graph of a pressure waveform acquired by a feature extraction unit when a dispensing nozzle aspirates and discharges air (the solid line is an example of an abnormal state where there is water leakage due to a faulty flow path, and the dotted line is an example of a normal state where there is no water leakage).

[0009] An automatic analyzer and a water leakage detection method thereof according to an embodiment of the present invention will be described below with reference to the drawings.

[0010] The configuration and operation of an automatic analyzer according to Example 1 will be described with reference to Figures 1 to 6. First, the configuration of the automatic analyzer according to Example 1 will be described with reference to Figure 1. Figure 1 is a schematic diagram of the automatic analyzer.

[0011] As shown in FIG. 1, the automatic analyzer 100 comprises a conveying line 101, a reagent disk 103, a reaction disk 104, a dispensing mechanism 105, a stirring mechanism 106, a spectroscope 107, a control unit 115, an input unit 123, a display unit 124, and the like.

[0012] The transport line 101 transports a sample rack 111 holding sample containers 110 containing samples (specimens) to a sample dispensing position 121. A dispensing mechanism 105 dispenses the sample from the sample container 110 into a reaction cell 112 (reaction container) at the sample dispensing position 121. The transport line 101 is further connected to a rotor 102. By rotating the rotor 102, the sample rack 111 is transferred between other transport lines 101.

[0013] The reagent disk 103 holds reagent containers 113 containing reagents, and rotates to transport the reagent containers 113 to a reagent dispensing position 122. The dispensing mechanism 105 dispenses the reagent from the reagent containers 113 into the reaction cells 112 at the reagent dispensing position 122. The reagent is dispensed into the reaction cells 112 in an amount required for colorimetric analysis, and reacts with components in the sample to be analyzed.

[0014] The reaction disk 104 holds reaction cells 112 and rotates to transport the reaction cells 112, which are the targets of each operation, to positions where the spectrometer 107 that performs colorimetric analysis, the stirring mechanism 106, the reaction cell cleaning mechanism 108, etc. operate. The reaction cells 112 are surrounded by a liquid such as water, which is maintained at a constant temperature. This promotes chemical reactions between the components in the specimen and the reagent in the reaction solution, which is a mixture of the specimen and the reagent.

[0015] The dispensing mechanism 105 aspirates a sample to be subjected to colorimetric analysis from a sample container 110 and dispenses it into a reaction cell 112, and also aspirates a reagent appropriate for the analysis target from a reagent container 113 and dispenses it into the reaction cell 112. The dispensing mechanism 105 includes an arm 118, a dispensing mechanism motor 119, a dispensing nozzle 116, a dispensing flow path 125, a pressure sensor 126, a dispensing syringe 127, a solenoid valve 128, etc. The arm 118 holds the dispensing nozzle 116 and a liquid level sensor 117. The liquid level sensor 117 detects the presence or absence of liquid based on a change in capacitance. A shield unit 114 is installed near a position where the dispensing mechanism 105 performs a dispensing operation. The dispensing mechanism motor 119, the pressure sensor 126, the dispensing syringe 127, the solenoid valve 128, etc. are electrically connected to the control unit 115. The dispensing mechanism motor 119 moves the dispensing mechanism 105 in the vertical direction or in the rotational direction. The dispensing nozzle 116, dispensing channel 125, pressure sensor 126, dispensing syringe 127, and solenoid valve 128 will be described later with reference to FIG.

[0016] The stirring mechanism 106 stirs the reaction liquid in the reaction cell 112 to promote the reaction between the components to be analyzed in the sample dispensed from the sample container 110 into the reaction cell 112 and the reagent dispensed from the reagent container 113 into the reaction cell 112.

[0017] The LED light source 120 irradiates the reaction solution that has undergone a chemical reaction while being stirred by the stirring mechanism 106 with output light. The spectroscope 107 separates the transmitted light that has passed through the reaction solution. Based on the separated transmitted light, colorimetric analysis is performed by measuring absorbance.

[0018] The reaction cell cleaning mechanism 108 cleans the reaction cell 112 by sucking the reaction liquid from the reaction cell 112 after the colorimetric analysis has been completed, and discharging and sucking detergent or the like.

[0019] The nozzle cleaning mechanism 109 cleans the tip of the dispensing nozzle 116 of the dispensing mechanism 105 that has dispensed a sample or reagent. This removes any residue adhering to the dispensing nozzle 116, preventing it from affecting the next analysis target.

[0020] The input unit 123 is composed of a keyboard, a mouse, a touch panel, etc., and inputs instructions from the user to the control unit 115. The display unit 124 is composed of an LCD (Liquid Crystal Display) etc., and displays an operation screen and the like.

[0021] The control unit 115 is composed of a processor, memory, etc., and controls the operation of each mechanism within the automatic analyzer 100, and performs arithmetic processing to determine the concentration of a predetermined component in a specimen (liquid) such as blood or urine. The control unit 115 also determines whether there is a leak in the dispensing mechanism 105 based on changes in pressure data associated with the suction or discharge of air by the dispensing nozzle 116, as will be described later.

[0022] The configuration of the automated analyzer 100 described above is merely one example, and it is possible to provide a separate sample disk for holding samples without providing the transport line 101 or rotor 102, or to provide a separate sample pretreatment system for performing various pretreatments on the samples. Furthermore, although Fig. 1 shows an example of the automated analyzer 100 as a device for measuring biochemical items, the present invention can also be applied to automated analyzers that perform different analyses, such as immunological items, in addition to biochemical items.

[0023] 2 and 3, the configuration of the dispensing mechanism 105 and the process of leak detection in the dispensing mechanism 105 will be described. The dispensing mechanism 105 that is the subject of leak detection may be for a specimen or a reagent.

[0024] FIG. 2 is a schematic diagram showing the configuration of the dispensing mechanism. As shown in FIG. 2, the dispensing mechanism 105 includes a dispensing nozzle 116, a dispensing flow path 125, a dispensing syringe 127, a pump 132, a solenoid valve 128, a pressure sensor 126, and the like. The dispensing nozzle 116 dispenses a specimen or a reagent. The dispensing flow path 125 communicates among the dispensing nozzle 116, the pressure sensor 126, the dispensing syringe 127, the solenoid valve 128, and the like. The dispensing syringe 127 (pressure generating source) generates pressure in the dispensing nozzle 116 for aspirating or discharging the specimen or reagent by driving it vertically with the solenoid valve 128 closed. The pump 132 generates pressure for supplying internal washing water for cleaning the inside of the dispensing nozzle 116. The solenoid valve 128 is provided in the dispensing flow path 125 between the pump 132 and the dispensing syringe 127, and opens and closes the dispensing flow path 125. The solenoid valve 128 is open only when internal washing water is supplied, and is closed during other times such as when aspirating or dispensing specimens or reagents, or when on standby. The pressure sensor 126 detects the pressure within the dispensing flow path 125. The opening and closing of the solenoid valve 128 and the operation of the dispensing syringe 127 are controlled by the control unit 115 (omitted from FIG. 2 ). Since the pump 132 is basically always running during operation of the automated analyzer 100, the control unit 115 can adjust the state of the fluid and pressure within the dispensing flow path 125 by controlling the opening and closing of the solenoid valve 128.

[0025] Fig. 3 is a block diagram of the configuration related to the water leak detection process using pressure data detected by the pressure sensor. As shown in Fig. 3, the water leak detection system is composed of a pressure sensor 126, an amplifier 129, an A / D converter 130, a feature extraction unit 131, a control unit 115, a display unit 124, etc. The amplifier 129 amplifies the pressure waveform data acquired by the pressure sensor 126 and outputs it to the A / D converter 130. The A / D converter 130 converts the pressure data amplified by the amplifier 129 into a digital signal and outputs it to the feature extraction unit 131.

[0026] After receiving the pressure data converted into a digital signal from the A / D converter 130, the feature extraction unit 131 extracts feature values ​​(determination values) for water leakage determination and sends the extracted feature values ​​to the control unit 115. Here, extracting feature values ​​means calculating, from the acquired pressure data, feature values ​​such as the average pressure value (hereinafter simply referred to as the "average pressure value") for a predetermined period (a period corresponding to a peak or trough of the pressure waveform), the oscillation time width of the pressure waveform, and the oscillation frequency of the pressure waveform. Details of the method for extracting each feature value in the feature extraction unit 131 will be described later.

[0027] As shown in FIG. 3 , the control unit 115 includes a memory unit 115a, a feature comparison unit 115b, and an abnormality determination unit 115c. The memory unit 115a stores pressure data converted into digital signals by the A / D converter 130, feature values ​​extracted by the feature extraction unit 131, various threshold values ​​set for each solenoid valve 128 or each dispensing mechanism 105, and the like. The threshold values ​​are used to determine the presence or absence of a water leak and are set in advance based on pressure data acquired when the dispensing mechanism 105 is in a normal state with no water leak. The feature comparison unit 115b compares the feature values ​​extracted by the feature extraction unit 131 with the threshold values ​​stored in the memory unit 115a and sends the comparison result to the abnormality determination unit. The abnormality determination unit 115c uses the comparison result from the feature comparison unit 115b to determine the presence or absence of a water leak in the dispensing mechanism 105.

[0028] When the abnormality determination unit 115c determines that there is a water leak (abnormality), an alarm display signal is output to the display unit 124, and a warning screen is displayed on the display unit 124. This allows the operator to take action, such as replacing the seal piece. In addition, the control unit 115 stops the sample analysis operation. The warning screen can be displayed in various ways, such as displaying a message such as "Water Leak" or displaying a warning light indicating there is a water leak. On the other hand, when the abnormality determination unit 115c determines that there is no water leak (normality), the pressure data converted into a digital signal by the A / D converter 130 and the feature extracted by the feature extraction unit 131 are stored in the memory unit 115a, and the analysis operation is started or continued.

[0029] 2 and 3 are merely examples. For example, the feature extraction unit 131 may be provided within the control unit 115, or may be considered as part of a broader control unit. Also, a control unit that controls the operation of each mechanism and determines the component concentrations may be provided separately from a control unit for the water leakage determination system.

[0030] Here, the method for extracting each feature in the feature extraction unit 131 and the comparison method in the feature comparison unit 115b will be described with reference to Figures 4 and 5. Figure 4 is a graph of the pressure waveform acquired by the feature extraction unit when the dispensing nozzle aspirates and dispenses air. The solid line shows an example of an abnormal state in which there is a leak due to a faulty solenoid valve, and the dotted line shows an example of a normal state in which there is no leak. The reason for aspirating and dispensing air rather than liquid is that when aspirating and dispensing liquid, the difference between normal and abnormal states is small, making it difficult to make a highly accurate judgment.

[0031] Before the dispensing nozzle 116 starts sucking air, the pressure is near 0 kPa (atmospheric pressure) regardless of whether there is a leak. During the period from the start to the end of air suction (first period), the pressure first swings in the negative (negative pressure) direction and then returns to near atmospheric pressure. During this first period, there is no significant difference between the pressure waveform when the solenoid valve is abnormal, such as when foreign matter has entered the solenoid valve 128, and the pressure waveform when it is normal. This is thought to be because the effect of driving the dispensing syringe 127 on pressure fluctuations is greater than the effect of the state of the solenoid valve 128 on pressure fluctuations.

[0032] Next, during the period from when the air suction ends to when the air discharge starts (second period), the pressure repeatedly fluctuates in the positive (positive pressure) direction and the negative (negative pressure) direction, gradually approaching atmospheric pressure. In particular, when there is an abnormality in the solenoid valve, pressure loss occurs inside the dispensing flow path 125 due to water leakage from the tip of the dispensing nozzle 116, so the pressure attenuates more than in a normal case, and the amplitude of the pressure waveform becomes smaller.

[0033] Then, during the period from the start to the end of air discharge (the third period), the pressure fluctuates in the positive (positive pressure) direction before returning to near atmospheric pressure. During this third period, no significant difference is observed between the pressure waveform when the solenoid valve is abnormal and the pressure waveform when it is normal. This is thought to be because the effect of the drive of the dispensing syringe 127 on pressure fluctuations is greater than the effect of the state of the solenoid valve 128 on pressure fluctuations.

[0034] Next, during the period from the end of air discharge to the start of dispensing mechanism 105 movement (period 4), the pressure repeatedly fluctuates in the negative (negative pressure) direction and the positive (positive pressure) direction, gradually approaching atmospheric pressure. In particular, when the solenoid valve is malfunctioning, pressure loss occurs inside dispensing flow path 125 due to water leakage from the tip of dispensing nozzle 116, resulting in greater pressure attenuation and a smaller amplitude of the pressure waveform than in a normal state. In other words, when the solenoid valve is malfunctioning, the oscillation time width, which is the time from the end of air discharge until the pressure attenuates to near atmospheric pressure and stabilizes, is shorter than in a normal state.

[0035] In this specification, for example, the oscillation time width of the pressure waveform after the end of air discharge is defined as "the time required from the start point at the end of air discharge to the end point at which the pressure fluctuation from the reference pressure value remains within ±0.5 kPa for a predetermined period of time or more." The reference pressure value may be 0 kPa or the pressure value acquired at the start of air suction. The predetermined period may be set to any value, such as 30 ms. For example, in FIG. 4, the oscillation time width in the normal case is indicated as Δt0, and the oscillation time width in the case of a solenoid valve abnormality is indicated as Δt1. Furthermore, the period for extracting the oscillation time width is not limited to the fourth period. If the pressure fluctuation also converges sufficiently in the second period, the oscillation time width may be extracted from the pressure waveform in the second period.

[0036] As described above, differences occur in the pressure waveform depending on whether or not there is a water leak. Therefore, the feature extraction unit 131 extracts from the pressure waveform an average pressure value, which is the average value of the pressure at the peak or valley portion of the pressure waveform in any of the first to fourth periods, as one of the feature values ​​for determining whether or not there is a water leak. The peak or valley portion of each period (the time period in which the peak or valley appears) may be identified based on the drive pattern of the dispensing syringe 127 pre-stored in the storage unit 115a, or may be identified based on the pressure waveform in a normal state. Furthermore, as described above, since there is no significant difference in the pressure waveform between the normal state and the abnormal state of the solenoid valve in the first and third periods, the feature extraction unit 131 may extract the average pressure value corresponding to the peak or valley only in the second and fourth periods.

[0037] Meanwhile, the pressure average value threshold, which is the criterion for determining whether or not there is a water leak, is stored in the memory unit 115a. In Fig. 4, P2 indicates the pressure average value threshold corresponding to the first peak in the pressure waveform for the second period, and P4 indicates the pressure average value threshold corresponding to the first valley in the pressure waveform for the fourth period. For example, a value whose amplitude is a predetermined amount smaller than the peak of a normal peak or valley is set as the pressure average value threshold. The feature amount comparison unit 115b then compares the pressure average value, which is the feature amount extracted by the feature amount extraction unit 131, with the pressure average value threshold stored in the memory unit 115a.

[0038] The feature extracting unit 131 may also extract the vibration time width described above as another feature for determining the presence or absence of a water leak. In this case, the feature comparing unit 115b compares the vibration time width extracted by the feature extracting unit 131 with a vibration time width threshold stored in the storage unit 115a to determine the presence or absence of a water leak. For example, a value that is a predetermined time shorter than Δt0, which is the vibration time width in the normal case, is set as the vibration time width threshold.

[0039] Furthermore, the feature extraction unit 131 may extract the vibration frequency of the pressure waveform as another feature for determining the presence or absence of a leak. Figure 5 is a graph of the vibration frequency distribution acquired by the feature extraction unit when the dispensing nozzle aspirates and dispenses air. The solid line shows an example of an abnormal state in which there is a leak due to a faulty solenoid valve, and the dotted line shows an example of a normal state in which there is no leak. The vibration frequency distribution shown in Figure 5 is calculated by applying a Fourier transform or other calculation to the pressure data acquired by the feature extraction unit 131 from the A / D converter 130. The pressure data used in the calculation may be normalized to atmospheric pressure or to the data at the first point.

[0040] As shown in Figure 5, in the normal case, a peak is observed at a predetermined low-frequency component, but in the case of a solenoid valve abnormality, the pressure is significantly attenuated and the amplitude of the pressure waveform is small, resulting in a peak at 0 Hz (DC component). Therefore, a value that is a predetermined amount smaller than the frequency at which the peak occurs in the normal case may be stored in the storage unit 115a as a vibration frequency threshold, and the presence or absence of a water leak may be determined based on whether a peak exists in a frequency range higher than this threshold. Furthermore, if the peak of the vibration frequency extracted by the feature extraction unit 131 is 0 Hz, it may be determined that there is a water leak without comparing it with the threshold.

[0041] As described above, the feature extraction unit 131 extracts feature quantities such as the average pressure value, the vibration time width of the pressure waveform, and the vibration frequency of the pressure waveform, and the feature comparison unit 115b performs a comparison using these feature quantities. However, the comparison method is not limited to comparison with the absolute value of a threshold. For example, the feature comparison unit 115b may compare whether the difference between the feature quantity in a normal state and the extracted feature quantity is within a predetermined range (threshold). Alternatively, the feature comparison unit 115b may calculate only the difference, and the abnormality determination unit 115c may determine the presence or absence of a water leak based on whether the difference is within a predetermined range.

[0042] Furthermore, the abnormality determination unit 115c may periodically monitor time-series changes in the characteristic quantities, etc. (e.g., the amount of change per unit time) based on the characteristic quantity and pressure waveform data accumulated in the storage unit 115a, and may diagnose that there is a sign of a water leak if there is a change that exceeds a predetermined tolerance. If there is a sign of a water leak as a result of such a sign diagnosis, the abnormality determination unit 115c may output a preventive alarm to the display unit 124. Furthermore, the abnormality determination unit 115c may predict the timing of a water leak, etc., by calculating an approximate curve from the time-series changes, and output a recommended timing of maintenance, etc., to the display unit 124.

[0043] Furthermore, the determination result by the abnormality determination unit 115c may be periodically transmitted to a server at a service center connected to the control unit 115 via a network or the like. This allows the service center to check the recommended maintenance timing, etc., and enables maintenance to be performed at the appropriate time. Also, by aggregating data from multiple automatic analyzers in the server at the service center and performing machine learning or the like, it is possible to improve the accuracy of the threshold value used to determine water leakage.

[0044] The above-described pressure data acquisition and leak detection are performed at least at one of the following times: during analysis preparation, during analysis, and during standby. This can be set to any timing, such as once an hour, in the morning, afternoon, or evening. However, to prevent waste of samples and reagents, it is desirable to perform leak detection during analysis preparation. Note that "during analysis preparation" refers to the time when various startup processes are being performed after the automatic analyzer 100 is started up, "during analysis" refers to the time when the automatic analyzer 100 is analyzing samples, and "during standby" refers to the time when the automatic analyzer 100 is idle and not analyzing samples.

[0045] In particular, during analysis by the automated analyzer 100, the air separating the pressure transmission medium (system water) filling the dispensing flow path 125 from the sample or reagent to be dispensed is aspirated before the sample or reagent is aspirated to prevent changes in concentration due to mixing of the pressure transmission medium and the sample or reagent. Therefore, when acquiring pressure data and determining whether there is a leak during analysis, it is desirable to utilize the timing of aspirating this air. Since the air is aspirated each time a sample or reagent is dispensed, this has the advantage of allowing leak determination to be performed frequently. As a result, even if a leak occurs during analysis, it can be immediately determined to be a leak.

[0046] Next, the flow of processing performed by the automatic analyzer 100 when determining whether there is a water leak will be described with reference to Fig. 6. Fig. 6 is a flowchart showing the operation of the automatic analyzer when determining whether there is a water leak in the first embodiment.

[0047] First, controller 115 supplies internal wash water to dispensing flow path 125 with solenoid valve 128 open, thereby cleaning the inside of dispensing nozzle 116 (step S601). By performing internal washing in this manner before air is sucked into dispensing nozzle 116 for leak detection, the conditions of dispensing nozzle 116 and dispensing flow path 125 can be set to the same conditions each time, even when leak detection is performed multiple times, improving the accuracy of leak detection.

[0048] Thereafter, the control unit 115 drives the pressure sensor 126 to start acquiring pressure data within the dispensing channel 125 (step S602). Furthermore, the control unit 115 drives the dispensing syringe 127 with the solenoid valve 128 closed to draw air into the dispensing nozzle 116 (step S603). Thereafter, the control unit 115 drives the dispensing syringe 127 with the solenoid valve 128 closed to eject air from the dispensing nozzle 116 (step S604). Once the ejection of air has finished, the control unit 115 ends acquisition of pressure data by the pressure sensor 126 (step S605).

[0049] Next, the feature extracting unit 131 extracts at least one of the average pressure value, the vibration time width of the pressure waveform, and the vibration frequency of the pressure waveform as a feature from the acquired pressure data (step S606).Then, the feature comparing unit 115b reads out a threshold value stored in advance in the storage unit 115a and compares the feature extracted in step S606 with the read threshold value (step S607).

[0050] If the comparison result in step S607 is within the threshold range (if the feature amount is equal to or greater than the threshold), the abnormality determination unit 115c determines that there is no water leakage (normal) and stores data such as the feature amount and pressure waveform in the storage unit 115a (step S608). Also, if the water leakage determination was made during the analysis preparation operation, the analysis is started, if the water leakage determination was made during the analysis operation, the analysis is continued or resumed, and if the water leakage determination was made during standby, the system returns to standby mode (step S609).

[0051] On the other hand, if the comparison result in step S607 is outside the threshold range (if the feature amount is less than the threshold), the abnormality determination unit 115c determines that there is a water leak (abnormality) and outputs a water leak alarm to the display unit 124 (step S610).If the water leak detection is made during analysis operation, the analysis operation is stopped (step S611).

[0052] Example 2 will be described with reference to Figures 7 to 9. The automatic analyzer of Example 2 is basically the same in configuration as the automatic analyzer of Example 1, but unlike Example 1, it not only determines whether or not there is a water leak, but also identifies the location of the cause of the water leak.

[0053] According to Example 1, if a leak is determined to exist, an alarm is output and the automatic analyzer 100 is stopped, thereby preventing the waste of specimens, reagents, and time. However, during subsequent maintenance, it is necessary to investigate the cause of the leak. This is because the cause of leaks from the dispensing mechanism 105 may not only be a malfunction of the solenoid valve due to the inclusion of foreign matter, but also a flow path malfunction due to damage to the dispensing flow path 125 or loosening of the flow path connection. Therefore, in Example 2, a threshold value is added to Example 1, allowing for more detailed comparison of feature quantities.

[0054] Next, a method for determining the presence or absence of a leak and the location of the cause in Example 2 will be described with reference to Figures 7 and 8. Figure 7 is a graph of the pressure waveform acquired by the feature extraction unit when the dispensing nozzle aspirates and dispenses air, with the solid line indicating an example of an abnormal state in which there is a leak due to a faulty flow path, and the dotted line indicating an example of a normal state in which there is no leak. Figure 8 is a graph of the same pressure waveform as Figure 4, i.e., the solid line indicating an example of an abnormal state in which there is a leak due to a faulty solenoid valve, but with predetermined thresholds (P3, P4', ΔTa, ΔTb) added to Figure 4.

[0055] 7 and 8, it can be seen that in the case of a leak caused by a faulty flow path, the amplitude of the pressure waveform is smaller overall than in the case of a leak caused by a faulty solenoid valve. This is because when there is a flow path abnormality, in addition to pressure loss due to leakage from the tip of the dispensing nozzle 116, pressure loss also occurs due to leakage from an abnormal part in the dispensing flow path 125. Furthermore, in the case of a flow path abnormality, the oscillation time width, which is the time from the end of air suction or discharge until the pressure decays to near atmospheric pressure and stabilizes, is even shorter than in the case of a solenoid valve abnormality. Three examples of typical determination methods that take these trends into consideration will be explained below.

[0056] The first determination method is to extract the average pressure values ​​of the peaks or valleys of the pressure waveform from the pressure data in the first and third periods, where the difference between the solenoid valve abnormality and the normal state was small, and compare them with the average pressure threshold value for these periods. In the examples of Figures 7 and 8, P3 is added as the average pressure threshold value corresponding to the peak portion in the third period. In the case of the flow path abnormality shown in Figure 7, the average pressure value of the peak portion in the third period is less than the threshold value P3 and can be considered to be an abnormality, while in the case of the solenoid valve abnormality shown in Figure 8, the average pressure value of the peak portion in the third period exceeds the threshold value P3 and cannot be considered to be an abnormality. Note that, if an average pressure threshold value corresponding to the valley portion is set for the first period as well, it is possible to determine whether or not a flow path abnormality exists, as in the third period.

[0057] Therefore, even if the extracted pressure average value is smaller than the threshold value and can be considered abnormal in the second or fourth period, if the extracted pressure average value is larger than the threshold value and cannot be considered abnormal in the first or third period, it can be determined that the leak is caused by a faulty solenoid valve.On the other hand, if the extracted pressure average value is smaller than the threshold value and can be considered abnormal in any period, it can be determined that the leak is caused by a faulty flow path.

[0058] Next, the second determination method will be described. In this method, two thresholds, one large and one small, are set for the second or fourth period, and the average pressure value extracted during that period is compared with these thresholds. In the examples of FIGS. 7 and 8 , in addition to P4, P4′ is added as an average pressure threshold corresponding to the valley portion of the fourth period. In the case of the flow path abnormality shown in FIG. 7 , the average pressure value during the valley portion of the fourth period is less than threshold P4 and less than threshold P4′. In the case of the solenoid valve abnormality shown in FIG. 8 , the average pressure value during the valley portion of the fourth period is less than threshold P4 but exceeds threshold P4′. Therefore, if the average pressure value extracted during the fourth period is between the two thresholds, a solenoid valve abnormality is determined, and if it is less than the two thresholds, a flow path abnormality is determined. Note that for the second period, if a threshold smaller in amplitude than threshold P2 is set in addition to threshold P2, it is possible to distinguish between a flow path abnormality and a solenoid valve abnormality, as in the fourth period.

[0059] Next, a third determination method will be described. In this method, two thresholds, large and small, are set for the oscillation time width instead of the pressure average value, and the extracted oscillation time width is compared with these thresholds. In the examples of FIGS. 7 and 8 , a smaller threshold ΔTa and a larger threshold ΔTb are added as oscillation time width thresholds for the fourth period. In the case of the flow path abnormality shown in FIG. 7 , the oscillation time width Δt2 for the fourth period is less than the threshold ΔTb and less than the threshold ΔTa. In the case of the solenoid valve abnormality shown in FIG. 8 , the oscillation time width Δt1 for the fourth period is less than the threshold Δb but greater than the threshold Ta. Therefore, if the oscillation time width extracted for the fourth period is between the two thresholds, a solenoid valve abnormality is determined. If the oscillation time width is smaller than the two thresholds, a flow path abnormality is determined. Depending on the pressure waveform, setting two thresholds, large and small, can also be used in the second period to distinguish between a flow path abnormality and a solenoid valve abnormality, as in the fourth period.

[0060] Next, the processing flow of the automatic analyzer 100 when determining whether there is a water leak will be described with reference to Fig. 9. Fig. 9 is a flowchart showing the operation of the automatic analyzer when determining whether there is a water leak in Example 2. Here, of the three determination methods described above, the first determination method will be described as an example.

[0061] First, steps S901 to S909 in Fig. 9 are the same as steps S601 to S609 in Fig. 6. However, in this embodiment, if the determination result in step S907 is outside (less than) the range of the threshold for the second or fourth period, the feature amount comparison unit 115b reads out the threshold for the first or third period that is stored in advance in the storage unit 115a, and compares the feature amount extracted for that period with the read threshold (step S910).

[0062] If the comparison result in step S910 is within the threshold range (if the feature amount is equal to or greater than the threshold), that is, if only the second and fourth periods out of the first to fourth periods are outside the threshold range, the abnormality determination unit 115c determines that there is a solenoid valve abnormality and outputs a solenoid valve malfunction alarm to the display unit 124 (step S911).If the water leakage detection is made during the analysis operation, the analysis operation is stopped (step S912).

[0063] On the other hand, if the determination result in step S910 is outside the threshold range (if the feature amount is less than the threshold), that is, if all of the first to fourth periods are outside the threshold range, the abnormality determination unit 115c determines that there is a flow path abnormality and outputs a flow path failure alarm to the display unit 124 (step S913).Furthermore, if a water leak is detected during the analysis operation, the analysis operation is stopped (step S914).

[0064] In the second and third determination methods, in which multiple thresholds are set within the same period, the comparison method in step S910 of the aforementioned steps is different, but the other steps are the same as in the first determination method.

[0065] The present invention is not limited to the above-described embodiments and includes various modifications. For example, a diaphragm, a micropump, or the like may be used as a negative pressure generating source in addition to a syringe. Furthermore, the above-described determination method using a threshold value is merely an example, and other methods may be used as appropriate depending on the structure of the dispensing mechanism, etc.

[0066] 101...Transport line, 102...Rotor, 103...Reagent disk, 104...Reaction disk, 105...Dispensing mechanism, 106...Stirring mechanism, 107...Spectrometer, 108...Reaction cell cleaning mechanism, 109...Nozzle cleaning mechanism, 110...Sample container, 111...Sample rack, 112...Reaction cell, 113...Reagent container, 114...Shield unit, 115...Control unit, 115a...Storage unit, 115b...Feature comparison unit, 115c ...abnormality determination unit, 116...dispensing nozzle, 117...liquid level sensor, 118...arm, 119...motor for dispensing mechanism, 120...LED light source, 121...sample dispensing position, 122...reagent dispensing position, 123...input unit, 124...display unit, 125...dispensing flow path, 126...pressure sensor, 127...dispensing syringe, 128...solenoid valve, 129...amplifier, 130...A / D converter, 131...feature extraction unit, 132...pump.

Claims

1. a dispensing nozzle for dispensing a sample or a reagent; a pressure generating source that generates pressure within the dispensing nozzle; a flow path that connects the pressure generating source and the dispensing nozzle; a pressure sensor that detects the pressure in the flow path; an electromagnetic valve provided in the flow path to open and close the flow path; a control unit that determines whether or not there is a water leak based on a change in pressure data during a fourth period after the dispensing of the air sucked by the dispensing nozzle has finished; An automatic analyzer comprising:

2. The automatic analyzer according to claim 1, The control unit extracting an average pressure value of the peaks or valleys of the pressure waveform from the pressure data; An automatic analyzer characterized by determining the presence or absence of a water leak by comparing the extracted pressure average value with a predetermined pressure average value threshold.

3. The automatic analyzer according to claim 2, The control unit is characterized in that it extracts the average pressure value of the peaks or valleys of the pressure waveform from the pressure data during a second period from the end of the air suction to the start of the air discharge.

4. The automatic analyzer according to claim 3, The control unit extracting an average pressure value of the peaks or valleys of the pressure waveform from the pressure data during the first period during the suction of the air or the pressure data during the third period during the discharge of the air; If the extracted pressure average values ​​in the second period and the fourth period are smaller than the respective pressure average value threshold values, and if the extracted pressure average values ​​in the first period and the third period are larger than the respective pressure average value threshold values, it is determined that an abnormality has occurred in the solenoid valve; An automatic analyzer characterized in that if the extracted pressure average value is smaller than the respective pressure average value threshold value in any of the first period, the second period, the third period, and the fourth period, it is determined that there is an abnormality in the flow path.

5. The automatic analyzer according to claim 1, The control unit extracting an oscillation time width of a pressure waveform from the pressure data in a fourth period after the discharge of air is completed; An automatic analyzer characterized by determining the presence or absence of a water leak by comparing the extracted vibration time width with a predetermined vibration time width threshold.

6. The automatic analyzer according to claim 3 or 5, The pressure average value threshold or the vibration time width threshold has two thresholds, a large one and a small one, within one period, The control unit If the extracted pressure average value or oscillation time width is between two threshold values, it is determined that the solenoid valve is abnormal; An automatic analyzer characterized in that, when the extracted pressure average value or oscillation time width is smaller than either of the threshold values, it is determined that there is an abnormality in the flow path.

7. The automatic analyzer according to claim 1, The control unit extracting an oscillation frequency of a pressure waveform from the pressure data; An automatic analyzer that determines whether or not there is a water leak by comparing the extracted vibration frequency with a predetermined vibration frequency threshold.

8. The automatic analyzer according to claim 1, The automatic analyzer is characterized in that the control unit cleans the inside of the dispensing nozzle before the air is sucked into the dispensing nozzle.

9. The automatic analyzer according to claim 1, An automatic analyzer characterized in that, when the pressure data acquisition and leak determination are performed during analysis operation, the air is aspirated before aspirating the sample or the reagent, and is segmented air that separates the system water in the dispensing nozzle from the sample or the reagent.

10. A method for determining whether a water leak exists in an automatic analyzer, the method comprising: a dispensing nozzle for dispensing a specimen or a reagent; a pressure generating source for generating pressure in the dispensing nozzle; a flow path connecting the pressure generating source and the dispensing nozzle; a pressure sensor for detecting pressure in the flow path; and a control unit for determining whether a water leak exists based on pressure data acquired from the pressure sensor, the dispensing nozzle aspirating or expelling air; a step in which the pressure sensor detects a change in pressure data in the flow path due to the suction or discharge of the air; the control unit extracts at least one of an average pressure value of peaks or valleys of the pressure waveform, an oscillation time width of the pressure waveform, and an oscillation frequency of the pressure waveform from the pressure data, and compares the extracted value with a predetermined threshold value; and 10. A method for determining a water leak in an automatic analyzer, comprising the step of: the control unit cleaning the inside of the flow path and the dispensing nozzle before the step of the dispensing nozzle aspirating or discharging air.

11. (delete)

12. The water leakage detection method for an automatic analyzer according to claim 10, A method for determining a water leak in an automatic analyzer, characterized in that when the acquisition of pressure data and the water leak determination are performed during an analysis operation, the air is aspirated before aspirating the sample or the reagent, and is segmented air that separates the system water in the dispensing nozzle from the sample or the reagent.