JP7471168B2 - Automatic analyzer and method for acquiring gear pump status of automatic analyzer - Google Patents

Description

The present invention relates to an automatic analyzer and a method for acquiring the status of a gear pump of an automatic analyzer.

In an automated analyzer, a liquid supply mechanism called a dispensing mechanism aspirates a predetermined amount of sample and reagent from a sample container that holds the sample for analysis and a reagent container that holds the reagent, respectively, and performs a dispensing operation in which the samples and reagents are mixed and discharged into a reaction container where they are reacted. The dispensing mechanism aspirates and discharges liquid by changing the pressure inside the nozzle using a syringe. That is, the pressure inside the nozzle is made negative and a predetermined amount of liquid is aspirated inside, and then the pressure is changed to positive pressure and discharged into the reaction container.

Since the nozzle of the dispensing mechanism dispenses different samples and reagents depending on the type and item of analysis, in an automatic analyzer, the nozzle is washed after aspirating and dispensing one sample or reagent and before starting the next dispensing operation. Nozzle washing can be done by external washing, in which a cleaning solution is sprayed onto the outside of the nozzle, and internal washing, in which a cleaning solution is discharged into the inside of the nozzle. If sufficient washing is not performed in these nozzle washing processes, the sample or reagent used in the previous dispensing operation may remain in the nozzle, causing contamination and affecting the analysis results.

Here, the cleaning water for external washing and internal washing (hereinafter, sometimes referred to as external washing water and internal washing water, respectively) is drawn into the automatic analyzer by the water supply pump via the water supply tank. After this, the internal washing water passes through a gear pump and reaches a pressure of about 330 kPa at a position in the piping near the gear pump (for example, near the outlet of the internal washing water). In order to thoroughly wash the inside of the nozzle, a certain level of pressure must be applied, but the pressure may decrease due to deterioration of the gear pump over time or wear during abnormal conditions such as empty operation. In addition to factors such as deterioration or failure of such flow path parts, a decrease in pressure in the flow path may occur due to user maintenance errors. For example, when removing the water supply tank for periodic cleaning, it is necessary to close the cock between the main body of the automatic analyzer and the water supply tank, and then open it again after cleaning. However, if the cock is not opened by mistake after cleaning by the user, the internal washing water is not supplied to the device, and as a result, the pressure may be lower than that required for internal washing of the nozzle.

Automated analyzers are generally equipped with a pressure meter that mechanically (hereafter referred to as analog) measures and displays the pressure of the gear pump or water supply pump. However, because the value indicated by this pressure meter is not numerical information, it cannot be automatically imported into the device and used for control. Therefore, even if an abnormality occurs in the analysis results due to the above-mentioned pressure fluctuations, the user cannot easily determine the cause, and in many cases the cause becomes clear only after a service technician visually checks the pressure meter.

Therefore, Patent Document 1 discloses a system in which a digital pressure sensor is installed in the pipe connecting the nozzle and syringe instead of an analog pressure meter, and the output value of this pressure sensor is input into the device to detect deterioration or failure of flow path components such as a gear pump.

JP 2014-025812 A

However, in the above-mentioned Patent Document 1, it is necessary to provide a dedicated pressure sensor in the device to capture the gear pump pressure as a digital value, which may lead to an increase in size and complexity of the device configuration. Furthermore, the complexity of the structure increases the risk of failure and may make it difficult to respond when a failure occurs.

The object of the present invention is to provide an automatic analyzer and a method for acquiring the gear pump status of an automatic analyzer that can easily acquire the status of a gear pump while preventing the device configuration from becoming larger and more complicated.

In order to solve the above problems, the present invention provides an automatic analyzer comprising a gear pump that delivers cleaning water for cleaning a dispensing mechanism, a pressure meter that measures in analog terms the pressure at which the cleaning water is delivered by the gear pump, and a control device, the automatic analyzer comprising a reaction tank that holds a constant temperature liquid for immersing a reaction vessel in which the sample and the reagent are reacted, and a sensor that measures the level or volume of the cleaning water delivered to the reaction tank via the dispensing mechanism, the control device comprising a memory unit that stores a predetermined correlation between a measured delivery pressure of the cleaning water by the gear pump and a measured time required for the level or volume of the cleaning water delivered from the gear pump to reach a predetermined value, and a status acquisition unit that acquires the status of the gear pump based on the correlation between the determination time measured by the sensor and the correlation stored in the memory unit.

The present invention provides an automatic analyzer and a method for acquiring the gear pump status of an automatic analyzer that can easily acquire the status of a gear pump while preventing the device configuration from becoming larger and more complicated.

FIG. 1 is a top view showing a basic configuration of an automatic analyzer according to an embodiment. FIG. 1 is a side view showing a basic configuration of a dispensing unit in an automatic analyzer according to an embodiment. FIG. 1 is a functional block diagram showing a control device according to an embodiment of the present invention; 1 is a flowchart showing a process for obtaining a correlation according to an embodiment. Flowchart showing the process for obtaining correlation using six dispensing mechanisms. A graph showing the correlation between the pressure of a gear pump pressure meter and the dispensing nozzle discharge time A diagram explaining a method for calculating a threshold value Flowchart showing a process for obtaining a judgment time Graph showing an example of a method for estimating the pressure of a gear pump based on a correlation and a judgment time period obtained in advance. A flowchart showing an operation for determining an abnormality in a gear pump, etc. A diagram of S804 to S806 in FIG. 10

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a top view showing the basic configuration of an automatic analyzer according to this embodiment. The automatic analyzer according to this embodiment includes a transport mechanism 2, a reaction disk 4, a reaction tank 5, a constant temperature liquid level sensor 6, a sample dispensing mechanism 13, a reagent disk 8, a first reagent dispensing mechanism 9, a second reagent dispensing mechanism 10, a reaction vessel cleaning mechanism 11, a spectrophotometer 12, and a control device 20. The transport mechanism 2 is capable of transporting a rack 1 capable of accommodating a plurality of sample vessels 1a that hold samples. The reaction disk 4 is a disk-shaped unit that can rotate clockwise and counterclockwise, and allows a plurality of reaction vessels 3 to be arranged on its circumference. The reaction tank 5 is a circular one that can accommodate a constant temperature liquid 24 in which the reaction vessels 3 are immersed. The constant temperature liquid level sensor 6 is for managing the level of the constant temperature liquid 24. The sample dispensing mechanism 13 is for dispensing a sample sucked from the sample vessel 1a into the reaction vessel 3. The reagent disk 8 can accommodate multiple reagent bottles 7 that hold reagents. The first reagent dispensing mechanism 9 and the second reagent dispensing mechanism 10 dispense reagents aspirated from the reagent bottles 7 in the reagent disk 8 into the reaction vessels 3. The reaction vessel cleaning mechanism 11 cleans the reaction vessels 3. The spectrophotometer 12 is installed near the outer periphery of the reaction disk 4 and measures the absorbance of the mixture of sample and reagent in the reaction vessel 3. The control device 20 controls the operation of the entire device and exchanges data with the outside.

Because the reaction vessel 3 is immersed in the constant temperature liquid 24 held in the reaction tank 5, if the constant temperature liquid 24 becomes cloudy, accurate measurement by the spectrophotometer 12 is not possible. Therefore, in order to prevent the constant temperature liquid 24 from becoming cloudy, the upper surface of the reaction tank 5 is covered with a circular upper cover 25 to prevent foreign matter from entering the constant temperature liquid 24 in the reaction tank 5. Furthermore, an antibacterial agent is added to the reaction tank 5 to prevent bacterial growth in the constant temperature liquid 24. When adding the antibacterial agent, the nozzle of the dispensing mechanism sucks up the antibacterial agent stored in the reagent bottle 7 (reagent container), and then adds the antibacterial agent from the antibacterial agent discharge hole 19 provided in the upper cover 25 of the constant temperature liquid 24. The constant temperature liquid 24 is supplied to the reaction tank 5 using a means (not shown) other than the dispensing mechanism.

The control device 20 is connected to a display unit 22 on which various parameters and settings are input, analysis test data for the initial test or retest, measurement results, etc. are displayed, and an input unit 23 for inputting various parameters and settings, analysis request information, instructions for starting analysis, etc. In addition, various parameters and settings, measurement results, analysis request information for samples contained in sample containers mounted on each sample rack, etc. are stored in a memory unit 207 of the control device 20.

Next, FIG. 2 is a side view showing the basic configuration of a dispensing system in an automatic analyzer according to this embodiment. Here, as an example, the configuration of the dispensing system relating to the first reagent dispensing mechanism 9 or the second reagent dispensing mechanism 10 will be described.

This dispensing system includes a water supply tank 36, a water supply tank cock 37, a water supply pump 38, a water supply pump pressure meter 39, a gear pump 40, a gear pump pressure meter 41, a high-pressure switching solenoid valve 42, a branch pipe 30, a solenoid valve 18, a first reagent dispensing mechanism 9 or a second reagent dispensing mechanism 10, and a dispensing syringe 16. The water supply tank 36 contains cleaning water to be supplied to the gear pump 40 and is removable. The water supply tank cock 37 is disposed in the flow path between the water supply tank 36 and the gear pump 40 and can be opened and closed, and separates the flow path when the water supply tank 36 is removed. The water supply pump 38 is connected to the water supply tank 36 by a pipe and supplies cleaning water, which is a pressure transmission medium. The water supply pump pressure meter 39 is connected to the flow path between the water supply pump 38 and the gear pump 40 and measures the pressure of the cleaning water in the water supply pump 38 in an analog manner. The gear pump 40 pressurizes the cleaning water supplied from the water supply pump 38. The gear pump pressure meter 41 is connected to the flow path of the gear pump 40 and the branch pipe 30, and measures the pressure of the cleaning water in an analog manner. The high-pressure switching solenoid valve 42 is disposed in the return flow path connecting the discharge side and the suction side of the gear pump 40. The branch pipe 30 is connected to the gear pump 40 by piping, and has one inlet and multiple outlets. The solenoid valve 18 is connected to the branch pipe 30, and enables opening and closing of each liquid flow path leading to the dispensing syringe. The tip of the first reagent dispensing mechanism 9 or the second reagent dispensing mechanism 10 has a dispensing nozzle 14 for aspirating and discharging a predetermined amount of liquid, and mainly aspirates and discharges samples such as blood and urine, and reagents. The dispensing syringe 16 controls the aspirating and discharging operation of a specified amount of cleaning water by changing the pressure inside the dispensing nozzle 14. Note that, although an example of a configuration in which the branch pipe 30 is connected to the first reagent dispensing mechanism 9 or the second reagent dispensing mechanism 10 has been described here, the other outlets of the multiple branch pipes 30 are connected to a dispensing mechanism of another system, such as the sample dispensing mechanism 13. The movable range of the dispensing nozzle 14 moved by the first reagent dispensing mechanism 9 or the second reagent dispensing mechanism 10 includes the reagent disk 8 carrying the reagent bottle 7 and the washing tank 35 for washing the nozzle. The operation of each of the above-mentioned components is controlled by the operation control unit 201 of the control device 20.

The procedure for dispensing a reagent based on this configuration is as follows. First, the second reagent dispensing mechanism 10 (first reagent dispensing mechanism 9) lowers the dispensing nozzle 14, and when it reaches the liquid of the reagent in the reagent bottle 7, the dispensing syringe 16 performs an aspirating operation of the reagent. When the aspirating operation of the reagent is completed, the dispensing nozzle 14 moves to the reaction vessel 3, and the dispensing syringe 16 performs an ejecting operation of the reagent into the reaction vessel 3. After dispensing is completed, the dispensing nozzle 14 moves to the washing tank 35, and the water supply pump 38 draws in the washing water in the water supply tank 36. The drawn-in washing water is made high pressure by the gear pump 40 and the high pressure switching solenoid valve 42, so that it becomes possible to wash the dispensing nozzle 14. The switching of the washing and ejecting is performed by the solenoid valve 18, and is controlled by the operation control unit 201 of the control device 20.

As mentioned above, the gear pump pressure meter 41 measures the pressure of the cleaning water near the gear pump 40 in an analog format, so in this state it cannot be imported into the device as digital information or used for control. Therefore, even if an abnormality occurs in the analysis results due to pressure fluctuations, the user cannot easily determine the cause.

Therefore, the control device 20 of this embodiment measures the pressure (measured delivery pressure) of the cleaning water by the gear pump 40 in advance using an analog gear pump pressure meter 41, and measures the time (measured time) required for the level or volume of the cleaning water delivered from the gear pump 40 to reach a predetermined value using a sensor, thereby storing the correlation. After that, the control device 20 acquires the status of the gear pump 40 (pressure estimation and abnormality judgment) based on the time (judgment time) required for the liquid level or volume to reach a predetermined value measured by the sensor and the correlation between the measured delivery pressure and the measured time. This method makes it possible to provide a low-cost, space-saving, and highly reliable automatic analyzer without using a complex configuration such as a digital pressure sensor. In addition, by using an analog pressure meter, the meter itself is less likely to malfunction, and even if an abnormality does occur, it is easy to repair, so time loss due to interrupting the analysis (operation) can be suppressed.

3 is a functional block diagram showing the control device 20 of this embodiment. As shown in FIG. 3, the control device 20 includes an operation control unit 201, an analysis unit 202, an abnormality determination unit 203 (gear pump status acquisition unit), a time measurement unit 204, a calibration curve creation unit 205, a threshold calculation unit 206, and a memory unit 207. The operation control unit 201 controls the operation of each dispensing mechanism and solenoid valve. The analysis unit 202 performs various controls for analyzing the sample. The abnormality determination unit 203 estimates the pressure of the gear pump 40 and determines abnormalities in the gear pump 40 and other components. The time measurement unit 204 monitors the sensor (constant temperature liquid level sensor 6) and measures the time required for the liquid level or volume to reach a predetermined value. The calibration curve creation unit 205 creates in advance a correlation between the measured delivery pressure and the measured time (hereinafter, sometimes referred to as a calibration curve). The threshold calculation unit 206 uses the correlation to calculate a threshold value for the determination time used for determination in the abnormality determination unit 203. The storage unit 207 stores the calibration curve created by the calibration curve creation unit 205, the threshold value calculated by the threshold calculation unit 206, and the like.

Figure 4 is a flow chart showing the process for obtaining the correlation according to this embodiment. In this embodiment, the correlation is obtained using two pieces of data: the measured delivery pressure and measured time when the high pressure switching solenoid valve 42 is closed and in a high pressure state, and the measured delivery pressure and measured time when the high pressure switching solenoid valve 42 is open and in a low pressure state. Figure 4(a) shows the flow for measuring pressure and time in a high pressure state, and Figure 4(b) shows the flow for measuring pressure and time in a low pressure state.

First, the measurement in a high-pressure state will be described with reference to FIG. 4(a). The operation control unit 201 of the control device 20 closes the high-pressure switching solenoid valve 42 to set the device in a high-pressure state (S301). After that, the operation control unit 201 of the control device 20 moves the dispensing nozzle 14 to the washing tank 35 and opens the solenoid valve 18 to discharge the internal washing water (S302). Here, while the internal washing water is being discharged, the serviceman adjusts the water supply pump pressure meter 39 by opening and closing the handle, and further visually measures the gear pump pressure meter 41 (S303). Next, the operation control unit 201 of the control device 20 opens the constant temperature liquid drain 43 to discharge the constant temperature liquid 24, and stabilizes the water level of the constant temperature liquid 24 by the constant temperature liquid level sensor 6 (S304).

Here, the constant temperature liquid level sensor 6 judges whether the sensor part is in contact with the constant temperature liquid 24 by ON or OFF, and when it is in the ON state where it is in contact with the constant temperature liquid 24, the constant temperature liquid drain 43 is opened to drain the constant temperature liquid 24. During this time, the constant temperature liquid level sensor 6 constantly monitors the sensor and stores the point in time when the sensor part turns OFF. The water level can be made constant by defining the time from this point in time until the constant temperature liquid 24 is completely drained. Furthermore, many devices use two constant temperature liquid level sensors 6, an upper limit and a lower limit, and in such cases, the water level can be made constant by draining the constant temperature liquid until the moment the lower limit sensor turns OFF. With two sensors, the variation in the discharge flow rate of the constant temperature liquid drain 43 is not included, so the water level of the constant temperature liquid 24 can be determined more accurately. During operation, the constant temperature liquid level sensor 6 is controlled to always be in the ON state.

After the level of the constant temperature liquid 24 becomes constant, the operation control section 201 of the control device 20 moves the dispensing nozzle 14 to the antibacterial agent discharge hole 19, and the dispensing nozzle 14 discharges the internal washing water (S305). At this time, the timing section 204 of the control device 20 stores the time from immediately after the discharge of the internal washing water starts until the constant temperature liquid water level sensor 6 turns ON (S306). Note that if the top cover 25 is not provided on the reaction tank 5, the location where the internal washing water is discharged from the dispensing nozzle 14 is not limited to the antibacterial agent discharge hole 19, and it may be discharged into the reaction tank 5 in any form.

Next, measurement in a low pressure state will be described with reference to FIG. 4(b). The operation control unit 201 opens the high pressure switching solenoid valve 42 to create a low pressure state (S311). After that, the operation control unit 201 moves the dispensing nozzle 14 to the washing tank 35 and opens the solenoid valve 18 to discharge the internal washing water (S312). Here, the serviceman measures the pressure meter while the internal washing water is being discharged (S313). Next, the operation control unit 201 uses the constant temperature liquid level sensor 6 to stabilize the level of the constant temperature liquid 24 (S314). After that, the operation control unit 201 moves the dispensing nozzle 14 to the antibacterial agent discharge hole 19 and discharges the internal washing water (S315), and the time measurement unit 204 measures the time until the constant temperature liquid level sensor 6 turns ON (S316).

The analog gear pump pressure meter 41 is measured by a serviceman, not an operator, to minimize reading errors. It is desirable to measure as few times as possible, so measurements are generally only taken when the device is set up. However, if there are changes to the internal wash water flow path components, such as the feed water pump, gear pump, solenoid valve, components of the dispensing mechanism, or the piping connecting them, measurements are required. In this embodiment, a configuration is described in which the constant temperature liquid level sensor 6 monitors the water level of the constant temperature liquid 24, but it is also possible to apply a configuration in which the water volume is monitored in place of the water level.

Figure 6 is a graph showing the correlation between the pressure of the gear pump pressure meter 41 and the dispensing nozzle discharge time according to this embodiment. In Figure 6, the horizontal axis is the pressure value obtained by measuring the scale of the gear pump pressure meter 41, and the vertical axis is the time it takes for the dispensing nozzle to discharge a specified amount of water, obtained by the constant temperature liquid level sensor 6. Also, (1) in Figure 6 is the result in the high pressure state described in Figure 4 (a), and (2) in Figure 6 is the result in the low pressure state described in Figure 4 (b). The calibration curve creation unit 205 of the control device 20 creates a calibration curve by connecting these two points (1) and (2). Also, the created calibration curve is stored in the memory unit 207 of the control device 20.

In addition, in FIG. 4, an example is described in which a calibration curve is created using one dispensing mechanism from two points: a high-pressure state in which the high-pressure switching solenoid valve 42 is closed, and a low-pressure state in which it is open. However, this is not limited to this, and it is also possible to create a calibration curve using five other dispensing mechanisms connected to the branch pipe 30.

Unlike the case of FIG. 4, FIG. 5 is a flowchart showing a process for obtaining a correlation (calibration curve) using six dispensing mechanisms. In the case of FIG. 5, the correlation is calculated using the following first and second data. The first data relates to the measured delivery pressure when cleaning water is discharged from only one dispensing nozzle, and the measured time from dispensing cleaning water from this one dispensing nozzle until the cleaning water reaches a predetermined value after being discharged from the one dispensing nozzle and being delivered to the reaction tank 5. The second data relates to the measured delivery pressure when cleaning water is discharged from six dispensing nozzles, and the measured time from dispensing cleaning water from the six dispensing nozzles until the cleaning water reaches a predetermined value after being delivered from one dispensing nozzle to the reaction tank 5.

Figure 5 (a) shows the flow of measuring pressure and time to obtain the first data, and Figure 5 (b) shows the flow of measuring pressure and time to obtain the second data. Unlike the case of Figure 4, Figure 5 has the advantage that it does not require processing with the high pressure switching solenoid valve 42 in the open state. In addition, as in normal operation, time can be measured under high pressure, so measurement accuracy is also high.

As shown in FIG. 5(a), the process for obtaining the first data has a flow similar to that of FIG. 4(a). On the other hand, as shown in FIG. 5(b), the process for obtaining the second data includes a flow different from that of FIG. 4, so this process will be described in detail.

The operation control unit 201 of the control device 20 closes the high pressure switching solenoid valve 42, then moves each of the six dispensing nozzles to the washing tank, opens the solenoid valve 18, and discharges the internal washing water to the six dispensing nozzles (S*12). While this internal washing water is being discharged, a serviceman measures the pressure meter (S*13). Next, after the water level of the constant temperature liquid 24 is stabilized, the operation control unit 201 moves only one dispensing nozzle, which is also used in FIG. 5(a), to the antibacterial agent discharge hole 19 and discharges the internal washing water into the reaction tank 5 (S*15). At this time, the remaining five dispensing nozzles each discharge the internal washing water into the washing tank. The time measurement unit 204 measures the time until the constant temperature liquid water level sensor 6 of the reaction tank 5 turns ON (S*16).

In addition to obtaining the correlation using the automatic analyzer, it is also possible to obtain the correlation in advance using another automatic analyzer having a similar configuration and store it in the memory unit 207. In this case, the abnormality determination unit 203 (status acquisition unit) can refer to the calibration curve when necessary to estimate the pressure of the gear pump 40, which has the advantage of eliminating the need to create a calibration curve.

Figure 8 is a flowchart showing the process for obtaining the judgment time, which is performed after the correlation is acquired. As described above, the abnormality judgment unit 203 (situation acquisition unit) of this embodiment is capable of estimating the pressure of the gear pump 40 based on the correlation and the judgment time acquired in advance.

As shown in FIG. 8, first, the operation control unit 201 of the control device 20 closes the high pressure switching solenoid valve 42 to make the pressure of the internal washing water the same high pressure as in operation (S601). After that, the constant temperature liquid level sensor 6 stabilizes the water level of the constant temperature liquid 24 (S602). Next, the operation control unit 201 moves the dispensing nozzle 14 to the antibacterial agent discharge hole 19, and the dispensing nozzle 14 discharges the internal washing water (S603). After that, the timing unit 204 measures the time until the constant temperature liquid level sensor 6 turns ON (S604).

Figure 9 is a graph showing an example of a method for estimating the pressure of the gear pump 40 based on a previously acquired correlation and a judgment time. As shown in Figure 9, when the measurement time (judgment time) by the constant temperature liquid level sensor 6 is, for example, 170 seconds, the abnormality judgment unit 203 (status acquisition unit) applies the calibration curve stored in the memory unit 207 to output 320 kPa as the estimated value of the gear pump pressure meter.

It is desirable to measure the judgment time for estimating the pressure of the gear pump 40 before operation, such as when starting up the device each day or when replacing the constant temperature liquid 24. In addition, it is possible to judge deterioration of the gear pump 40, forgetting to close the water supply tank cock 37, malfunction of the solenoid valve 18, etc., based on the judgment time and the calibration curve. By measuring the judgment time and judging an abnormality before operation, it is possible to guarantee measurement results without any malfunctions.

Here, a method for determining an abnormality in the gear pump 40, etc., based on a threshold value calculated from the calibration curve and the determination time will be described. First, the threshold value calculation unit 206 of the control device 20 calculates a first threshold value related to the determination time and a second threshold value larger than the first threshold value from the calibration curve.

Figure 7 is a diagram explaining a method for calculating the threshold value according to this embodiment. The first threshold value is the time for determining deterioration of the gear pump 40, and is determined from the specifications and calibration curve of the gear pump pressure meter 41. The specifications of the gear pump pressure meter 41 include a safety factor for the adjustment specification of 330 kPa that assumes wear of the gear pump 40, and may be set to 300 kPa, which is 10% less than the adjustment specification of 330 kPa. Based on this 300 kPa and the calibration curve, the first threshold value is determined to be 180 s.

The second threshold is the time required to determine whether the water supply tank cock 37 has been left closed or whether the solenoid valve 18 has malfunctioned. It is known that when the water supply tank cock 37 is closed, or when the solenoid valve 18 remains closed due to malfunction, the value of the gear pump pressure meter 41 is extremely low, at 100 kPa or less. Therefore, it is desirable to set the second threshold to a value extremely lower than the specification of 300 kPa for the gear pump pressure meter 41, for example, 210 kPa, which is 30% lower than the specification of 300 kPa. Based on this 210 kPa and the calibration curve, the second threshold is determined to be 215 s.

Figure 10 is a flow chart showing the operation for determining abnormalities in the gear pump 40, the water supply tank cock 37, and the solenoid valve 18. First, the threshold calculation unit 206 defines the first and second thresholds according to Figure 7 from the calibration curve obtained from Figure 4 or Figure 5 (S801). Next, the time measurement unit 204 measures the time (determination time) until the constant temperature liquid 24 reaches a predetermined water volume by the constant temperature liquid level sensor 6 based on Figure 8 (S802). Thereafter, the abnormality determination unit 203 compares the measured determination time with the first threshold (S803), and if the determination time is less than the first threshold, it processes as no abnormality (S851).

Next, if the judgment time is equal to or greater than the first threshold value and less than the second threshold value, the estimated value of the gear pump pressure meter 41 will be between 210 kPa and 300 kPa, which is outside the specification of 300 kPa, and therefore deterioration of the gear pump 40 is suspected.

However, the calibration curve may have changed due to various factors, such as changes in temperature and humidity, deterioration of the constant temperature liquid level sensor 6, deterioration of the dispensing nozzle 14, reading errors of the gear pump pressure meter 41, and bending or dirt of the constant temperature liquid drain 43. Therefore, if the judgment time is equal to or greater than the first threshold value and less than the second threshold value, the abnormality judgment unit 203 instructs the operator to check the gear pump pressure meter 41 via the display unit 22, etc. In response to this, if the operator checks the scale of the gear pump pressure meter 41 (S805) and finds that it is less than the specification of 300 kPa, the operator uses the input unit 23 to make a specified input. The abnormality judgment unit 203 then judges that the gear pump 40 has deteriorated and generates an alarm (S852). On the other hand, if the scale of the gear pump pressure meter 41 is equal to or greater than the specification of 300 kPa, the threshold calculation unit 206 corrects the threshold (S806), and the abnormality determination unit 203 processes the condition as no abnormality (S851).

Figure 11 illustrates steps S804 to S806 in Figure 10. For example, if the judgment time is 185 s, the estimated value of the gear pump pressure meter 41 is 290 kPa. However, if the operator checks the scale of the gear pump pressure meter 41 and finds it to be 300 kPa or more, the operator uses the input unit 23 to perform a predetermined input, and the input information is sent to the control device 20, and the threshold calculation unit 206 corrects the first threshold to 185 s. Next, the calibration curve creation unit 205 determines the point of contact (3) between this 185 s and the specification of 300 kPa, and creates a new calibration curve with the same slope as that of the calibration curve previously obtained. After that, the threshold calculation unit 206 can obtain the correction value 220 s of the second threshold by determining the point of contact (4) between the new calibration curve and 210 kPa, which is obtained by reducing the specification of 300 kPa by 30%.

Returning to the explanation of FIG. 10, if the judgment time is equal to or greater than the second threshold in S804, the estimated value of the gear pump pressure meter 41 is equal to or less than 210 kPa, which is far from the specification of 300 kPa, and therefore it is presumed that an abnormality other than deterioration of the gear pump 40 has occurred. Therefore, the operator checks whether the water supply tank cock 37 has been left closed (S807). If so, the water supply tank cock 37 is closed (S808) and the judgment time is measured again based on FIG. 8 (S802). On the other hand, if the cock has not been left closed, an alarm is generated indicating that the solenoid valve is malfunctioning (S853).

Reference Signs List 1a... Sample container 2... Transport mechanism 3... Reaction container 4... Reaction disk 5... Reaction tank 6... Constant temperature liquid level sensor 7... Reagent bottle 8... Reagent disk 9... First reagent dispensing mechanism 10... Second reagent dispensing mechanism 11... Reaction container cleaning mechanism 12... Spectrophotometer 13... Sample dispensing mechanism 14... Dispensing nozzle 16... Dispensing syringe 18... Solenoid valve 19... Antibacterial agent discharge hole 20... Control device 22... Display unit 23... Input Unit 24... Constant temperature liquid 25... Top cover 30... Branch pipe 35... Cleaning tank 36... Water supply tank 37... Water supply tank cock 38... Water supply pump 39... Water supply pump pressure meter 40... Gear pump 41... Gear pump pressure meter 42... High pressure switching solenoid valve 43... Constant temperature liquid drain 201... Operation control unit 202... Analysis unit 203... Abnormality determination unit 204... Time measurement unit 205... Calibration curve creation unit 206... Threshold calculation unit 207... Memory unit

Claims (10)

A dispensing mechanism for dispensing a sample or a reagent;
a gear pump that delivers cleaning water for cleaning the dispensing mechanism;
a pressure meter for measuring in analog form the pressure of the cleaning water discharged by the gear pump;
A control device;
An automatic analyzer comprising:
a reaction tank for holding a constant temperature liquid in which a reaction vessel in which the sample and the reagent are reacted is immersed;
a sensor for measuring the level or volume of the cleaning water delivered to the reaction tank via the dispensing mechanism ;
The control device includes:
a memory unit that stores a correlation between a measured pressure of the cleaning water discharged by the gear pump and a measured time required for the liquid level or volume of the cleaning water discharged from the gear pump to reach a predetermined value,
and a status acquisition unit that acquires the status of the gear pump based on the judgment time required for the level or volume of the cleaning water measured by the sensor to reach the specified value and the correlation stored in the memory unit. 2. The automatic analyzer according to claim 1,
The automatic analyzer according to claim 1, wherein the status acquisition unit estimates the pressure of the gear pump based on the determination time and the correlation. 2. The automatic analyzer according to claim 1,
The storage unit also stores a threshold value calculated from the correlation,
The automatic analyzer according to claim 1, wherein the status acquisition unit is an abnormality determination unit that determines an abnormality in the gear pump based on the determination time and the threshold value. 2. The automatic analyzer according to claim 1,
The automatic analyzer, wherein the correlation is obtained using the automatic analyzer. 2. The automatic analyzer according to claim 1,
a solenoid valve disposed in a return flow path connecting a discharge side and a suction side of the gear pump;
The correlation includes data of the measured delivery pressure and the measured time when the solenoid valve is in an open state, and data of the measured delivery pressure and the measured time when the solenoid valve is in a closed state. 2. The automatic analyzer according to claim 1 ,
The dispensing mechanism has a plurality of dispensing nozzles,
The correlation is
First data relating to the measured delivery pressure when the cleaning water is discharged from only a portion of the dispensing nozzles, and the measured time until the cleaning water is discharged from the portion of the dispensing nozzles and delivered to the reaction tank and reaches the predetermined value;
and second data relating to the measured delivery pressure when the cleaning water is ejected from a greater number of the dispensing nozzles than the first data, and the measured time until the cleaning water is ejected from the greater number of the dispensing nozzles and the cleaning water from some of the dispensing nozzles is delivered to the reaction tank and reaches the specified value. 4. The automatic analyzer according to claim 3,
the threshold value includes a first threshold value related to the determination time and a second threshold value greater than the first threshold value;
The abnormality determination unit
If the determination time is less than the first threshold value, it is determined that there is no abnormality;
When the determination time is equal to or greater than the first threshold value and is less than the second threshold value, it is determined that an abnormality exists in the gear pump;
When the determination time is equal to or greater than the first threshold value and equal to or greater than the second threshold value, the automatic analyzer determines that an abnormality exists in something other than the gear pump. 8. The automatic analyzer according to claim 7 ,
a water supply tank for supplying cleaning water to the gear pump;
an openable and closable cock disposed in a flow path between the water supply tank and the gear pump;
a solenoid valve disposed in a return flow path connecting the discharge side and the suction side of the gear pump;
The abnormality determination unit
The automatic analyzer is characterized in that, when the determination time is equal to or greater than the first threshold value and equal to or greater than the second threshold value, it is determined that there is an abnormality in the cock or the solenoid valve. 8. The automatic analyzer according to claim 7 ,
The abnormality determination unit
An automatic analyzer characterized in that even if the judgment time is equal to or greater than the first threshold value and less than the second threshold value, when it is confirmed that the pressure meter scale is equal to or greater than a predetermined value, it judges that there is no abnormality. 1. A gear pump status acquisition method for an automatic analyzer, which acquires a status of a gear pump that delivers cleaning water for cleaning a dispensing mechanism of a sample or a reagent, comprising:
measuring a pressure of the cleaning water discharged by the gear pump in advance with an analog pressure meter;
measuring in advance with a sensor a time required for the liquid level or volume of the cleaning water delivered from the gear pump to the reaction tank to reach a predetermined value;
storing a correlation between the delivery pressure and the time;
A method for acquiring the status of a gear pump in an automatic analyzer, comprising the steps of: acquiring the status of the gear pump based on the time required for the level or volume of the cleaning water to reach a predetermined value measured by the sensor and the correlation.

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