AUTOMATIC CHEMICAL ANALYZER, MAINTENANCE KIT FOR AUTOMATIC CHEMICAL ANALYZER, AND MAINTENANCE METHOD FOR AUTOMATIC CHEMICAL ANALYZER

Abstract

To provide an automatic chemical analyzer, and a maintenance kit and a maintenance method of the analyzer which, even when failure is caused to the analyzer, can identify factors of the failure so that the failure can be dealt with on a user's site without recalling the analyzer or its components.SOLUTION: A maintenance kit of an automatic chemical analyzer includes an agitation mechanism having: reaction containers 107 capable of storing dispensed samples and reagents; and a piezoelectric element 201 for irradiating the reaction containers 107 with an ultrasonic wave. The piezoelectric element 201 can be connected to the automatic chemical analyzer including a plurality of split electrodes 211 and measures an absolute value of an impedance of itself and a phase difference between an applied voltage and a current to the split electrodes 211 for each of the split electrodes 211, so as to determine the presence of abnormality of each of the split electrodes 211 on the basis of the measurement result.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an automatic chemical analyzer, and in particular to an automatic chemical analyzer having a stirring mechanism that mixes a mixture of a specimen and a reagent in a reaction vessel in a non-contact manner using ultrasound, and relates to an automatic chemical analyzer, a maintenance kit for the automatic chemical analyzer, and a maintenance method for the automatic chemical analyzer that realize maintenance of the stirring mechanism to always properly perform the stirring function. [Background technology]

[0002] According to the techniques disclosed in Patent Document 1, Patent Document 2, Patent Document 3, and Non-Patent Document 1, a technique for non-contact mixing of stirred liquids (sample and reagent) in a reaction vessel using the effect of the acoustic radiation pressure of ultrasound has been developed and implemented in an automatic chemical analyzer for practical use. In this technology, a sine wave or square wave with a frequency close to the thickness resonance frequency of the piezoelectric element is applied to the piezoelectric element to generate ultrasonic waves, which are then irradiated from outside the reaction vessel toward the liquid to be stirred and mixed. It is expected that an automatic chemical analyzer equipped with this ultrasonic non-contact stirring technology (hereinafter referred to as this stirring technology) will be used for several years after being installed at the user's site. Therefore, like other mechanisms that make up the automatic chemical analyzer (e.g., a dispensing mechanism or a cleaning mechanism, etc.), a function is required to check whether each stirring operation is being performed properly while the automatic chemical analyzer is in operation.

[0003] According to the technology disclosed in Patent Document 4, the current flowing through the piezoelectric element during each stirring operation is constantly measured and recorded, and by measuring whether a specified current is flowing, it is determined whether proper stirring has been performed. If the specified current value is not flowing, it is determined that the desired ultrasonic waves were not generated from the piezoelectric element, which is the ultrasonic wave transmission source, and an abnormality, error, or alert regarding the stirring operation is output to the automatic chemical analyzer to be presented to the user. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3641992 [Patent Document 2] Patent No. 3661076 [Patent Document 3] Patent No. 4406629 [Patent Document 4] Patent No. 3746239 [Patent Document 5] Patent No. 4112228 [Non-patent literature]

[0005] [Non-Patent Document 1] Chemical Engineering Science 60(2005) pp5519-5528 Summary of the Invention [Problem to be solved by the invention]

[0006] In the technology disclosed in the above-mentioned Patent Document 4, the stirring operation is performed once, and the presence or absence of an abnormality is determined by comparing the current waveform and value flowing through the piezoelectric element at that time with predetermined specified waveforms and values. However, it is difficult to determine which component of the stirring mechanism of the automatic chemical analyzer is defective using only the above-mentioned method. There are cases where it is necessary to replace not only the piezoelectric element, but also the power amplifier that drives the piezoelectric element, the relay circuit that selects the electrode to which the voltage is applied, etc. Furthermore, when these components that have been replaced and collected as defective products are examined, it is sometimes found that the piezoelectric element or the drive circuit system is not necessarily defective.

[0007] Therefore, the present invention provides an automatic chemical analysis apparatus, a maintenance kit for an automatic chemical analysis apparatus, and a maintenance method for an automatic chemical analysis apparatus that, in the unlikely event that a malfunction occurs in the automatic chemical analysis apparatus, enables the cause of the malfunction to be identified and addressed at the user's site without the need to recover the apparatus or parts. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention provides an automatic chemical analyzer that includes at least a reaction vessel capable of accommodating a dispensed specimen and a reagent, and a stirring mechanism having a piezoelectric element that irradiates ultrasonic waves to the reaction vessel, the piezoelectric element having a plurality of divided electrodes. A relay circuit for driving the piezoelectric element and an interface unit to which a power amplifier system can be connected, and a maintenance kit connectable to the interface unit, The absolute value of the impedance of the piezoelectric element and the phase difference between the voltage and current applied to the divided electrodes are measured for each divided electrode, and the presence or absence of an abnormality in each divided electrode is judged based on the measurement results. Determine It is characterized by the above.

[0009] In addition, the maintenance kit for an automatic chemical analyzer according to the present invention is a maintenance kit for an automatic chemical analyzer that comprises at least a reaction vessel capable of containing dispensed specimens and reagents, and a stirring mechanism having a piezoelectric element that irradiates ultrasonic waves into the reaction vessel, the piezoelectric element being connectable to an automatic chemical analyzer having a plurality of split electrodes, and is characterized in that the absolute value of the impedance of the piezoelectric element and the phase difference between the applied voltage and current to the split electrodes are measured for each split electrode, and the presence or absence of an abnormality in each split electrode is determined based on the measurement results.

[0010] In addition, the maintenance method for an automatic chemical analysis apparatus according to the present invention is a maintenance method for an automatic chemical analysis apparatus which includes at least a reaction vessel capable of containing dispensed specimens and reagents, and a stirring mechanism having a piezoelectric element which irradiates ultrasonic waves to the reaction vessel, the piezoelectric element having a plurality of split electrodes, and is characterized in that a maintenance kit is connected to the automatic chemical analysis apparatus via an interface section, and the maintenance kit measures the absolute value of the impedance of the piezoelectric element for each split electrode and the phase difference between the applied voltage and current to the split electrodes, and determines the presence or absence of an abnormality in each split electrode based on the measurement results. Effect of the Invention

[0011] According to the present invention, it is possible to provide an automatic chemical analysis apparatus, a maintenance kit for an automatic chemical analysis apparatus, and a maintenance method for an automatic chemical analysis apparatus, which, in the unlikely event that a malfunction occurs in the automatic chemical analysis apparatus, enable the cause of the malfunction to be identified and addressed at the user's site without the need to recall the apparatus or parts. For example, if some malfunction occurs in an automatic analyzer that employs a stirring method in which the electrode on one side of a piezoelectric element, which is a sound source that generates ultrasound, is divided and power is selectively supplied to that electrode to adjust the irradiation position from the sound source, the present invention can be used to measure the impedance spectrum (Impedance Spectrum: hereinafter referred to as ImpS) for each divided electrode to determine which position on the piezoelectric element has lost or damaged piezoelectricity of the divided electrode, and even to clarify whether there is anything wrong with the piezoelectric element itself and other causes of the malfunction, such as the power amplifier that supplies power and the relay circuit that selects the electrode. Problems, configurations and effects other than those described above will become apparent from the following description of the embodiments. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic diagram showing the overall configuration of an automatic chemical analyzer according to an embodiment of the present invention; [Diagram 2] FIG. 2 is an explanatory diagram of an ultrasonic non-contact stirring mechanism which is the stirring mechanism shown in FIG. [Diagram 3] FIG. 1 is an external perspective view of a maintenance kit for measuring ImpS (impedance spectrum) of a piezoelectric element that is a sound source for ultrasonic non-contact stirring according to an embodiment of the present invention. [Figure 4] FIG. 4 is a configuration diagram of an electronic circuit of the maintenance kit body shown in FIG. 3. [Figure 5A] FIG. 2 shows an example of an impedance profile of a normal piezoelectric element measured in water. [Figure 5B] FIG. 1 shows an example of an impedance profile of an abnormal piezoelectric element measured in water. [Figure 6A] FIG. 2 shows an example of an impedance profile of a normal piezoelectric element measured in water. [Figure 6B] FIG. 13 is a diagram showing an example of an impedance profile of a normal piezoelectric element measured in air or in a state where the thermostatic chamber is empty after the thermostatic water is discharged. [Figure 7A] FIG. 13 illustrates an example of a population distribution of resonant frequencies for each segment of a normal piezoelectric element. [Figure 7B] FIG. 13 illustrates an example of a population distribution of minimum impedances per segment for a normal piezoelectric element. [Figure 7C] FIG. 7B is a diagram showing an example of the distribution of resonance frequencies for each segment of a piezoelectric element measured using the population shown in FIG. 7A as a normal population. [Figure 7D] FIG. 7C is a diagram showing an example of the distribution of minimum impedance for each segment of a piezoelectric element measured using the population shown in FIG. 7B as a normal population. [Figure 8] FIG. 4 is a flowchart showing a maintenance method for an automated chemical analyzer, illustrating a process flow of a maintenance kit according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The electronic device parts used in this embodiment are the most suitable and easiest to procure at the time of filing the application, but there is a high possibility that more advanced electronic parts will be available in the future. If such parts can be substituted for the elements required in this invention, it is preferable to use them. EXAMPLES

[0014] First, the automated chemical analyzer and the stirring mechanism according to the present embodiment will be described.

[0015] [Configuration of the automatic chemical analyzer and mixing mechanism] FIG. 1 is a schematic diagram showing the overall configuration of an automatic chemical analyzer according to an embodiment of the present invention. As shown in FIG. 1, the automated chemical analyzer 1 includes a sample cup 101 containing each specimen, a sample disk 102 on which a plurality of sample cups are placed, a reagent cooling disk 104 for cooling a reagent bottle 103, and a sample dispenser 105 for dispensing specimens. , trial A reagent dispenser 106 is provided for dispensing medication. The specimen and the reagent are dispensed into the reaction vessels 107 by the sample dispenser 105 and the reagent dispenser 106, respectively. The reaction vessels 107 into which the specimen and the reagent have been dispensed are arranged along the circumferential direction on the reaction disk 108, which rotates clockwise in FIG. 1 and is mixed in a non-contact manner by the stirring mechanism 109 using ultrasonic waves. The reaction of the mixed specimen and the reagent is promoted, and the absorption characteristics are measured by the absorption spectrometer 110. The reaction vessels 107 containing the specimens for which the absorbance measurement, i.e., the analysis, has been completed are washed by the washing mechanism (not shown). After the washing is completed, the next specimen is dispensed, and the above-mentioned series of analysis sequences are repeated. The reaction vessels 107 arranged along the circumferential direction of the reaction disk 108 are in contact with the constant temperature water (not shown) circulating in the constant temperature bath 111, and are kept at a constant temperature via the constant temperature water at a specified temperature. The sample disk 102, reagent cooling disk 104, dispensing mechanism (sample dispenser 105 and reagent dispenser 106), reaction disk 108, etc. exchange signals with a host computer (not shown) mounted in the automatic chemical analyzer 1, and each operation sequence is controlled according to commands (signals) from the host computer. The stirring mechanism 109 is also connected to a relay circuit (not shown) for driving a piezoelectric element and a power amplifier system 113 via a connector 112, and the power amplifier system 113 also operates according to commands (signals) from the host computer. The connector 112 is also called an interface section.

[0016] Figure 2 is an explanatory diagram of the ultrasonic non-contact stirring mechanism which is the stirring mechanism shown in Figure 1. Figure 2 shows a cross-sectional view (on a plane stretched by two axes, the vertical direction and the radial direction of the reaction disk) of the stirring mechanism 109 shown in Figure 1. A signal 219 from the host computer via the connector 112 is also shown.

[0017] The stirring mechanism 109 is composed of a piezoelectric element 201, a jig 202 for mounting it in a thermostatic chamber 111, and a power amplifier system 113 for supplying power to the piezoelectric element. The electrode 210 of the piezoelectric element 201 on the constant temperature water 209 side is folded back along the lower end face of the element to the opposite side as shown in Fig. 2. The electrode on the surface opposite the constant temperature water 209 side is divided into a certain length and width as shown inside the dashed line in the drawing. Each divided electrode 211 is connected to each pin of the connector 112 in a one-to-one relationship.

[0018] The power amplifier system 113 includes a function generator circuit 205 that generates a drive waveform, a final amplifier circuit 206 that amplifies the waveform to a desired power, and a current monitor 207 that measures the current flowing through the piezoelectric element 201 by electromagnetic coupling when a voltage is applied as disclosed in Patent Document 4. Note that this embodiment is based on the premise that the current monitor 207 in the power amplifier system 113 monitors the presence or absence of abnormalities in the function generator circuit 205 and the final amplifier circuit 206 as disclosed in Patent Document 4, and in the present invention, the presence or absence of abnormalities on the piezoelectric element 201 side is detected by a maintenance kit described later. Inside this power amplifier system 113, a relay group 208 whose opening and closing is controlled by commands from the host computer is connected to each divided electrode 211 via a connector 112. An electrode at an appropriate position is selected from divided electrodes 211 by opening and closing relay group 208 according to the liquid level of the stirred liquid (mixture of specimen and reagent) in reaction vessel 107, and the irradiation position of ultrasonic waves on reaction vessel 107 is adjusted.

[0019] [Maintenance kit composition] 3 is an external perspective view of a maintenance kit for measuring the Impedance Spectrum (Impedance Spectrum) of a piezoelectric element, which is the sound source of ultrasonic non-contact stirring according to one embodiment of the present invention. The maintenance kit 2 is for checking the state of the stirring mechanism 109. As described above, by measuring the Imps of each divided electrode of the piezoelectric element 201, which is the sound source, at a user site where the automatic chemical analysis device 1 is installed, it is possible to diagnose whether the stirring mechanism 109 is normal or abnormal, and, if an abnormality occurs, to identify the cause of the abnormality.

[0020] As shown in FIG. 3, a maintenance kit main body 301 (Impedance Measurement Module: hereinafter referred to as IMM) is composed of an operation button 302 and a display 303 for displaying measurement results, etc., and is provided with a connector 305 via a signal line (cable) 304. This connector 305 is adapted to be connected to a connector 112 connected to a piezoelectric element 201 of a stirring mechanism 109 for ultrasonic non-contact stirring mounted on the automatic chemical analyzer 1, and when performing maintenance on the stirring mechanism 109 on the automatic chemical analyzer 1, the connector 112 is replaced with the connector of the power amplifier system 113 and connected to the connector 112, so that the ImpS of the piezoelectric element 201, which is a sound source, can be measured. The connector 305 of the maintenance kit 2 is also referred to as an interface unit. In this embodiment, the connection between the interface unit of the automatic chemical analyzer 1 and the interface unit of the maintenance kit 2 is a wired connection via a connector, but is not limited to this. For example, these interfaces may be connected wirelessly.

[0021] FIG. 4 is a configuration diagram of the electronic circuit of the maintenance kit main body (IMM) shown in FIG. 3. As shown in FIG. 4, inside the electronic circuit of the IMM, a digital direct synthesizer (hereinafter referred to as DDS) 401 generates a sine waveform voltage of an arbitrary frequency. The waveform voltage is amplified by an amplifier 402, and the sine waveform voltage is output to an output terminal 403. The sine waveform voltage output to the output terminal 403 is output to a connector 306 via a relay group 404 or a multiplexer (hereinafter referred to as an electrode switch). In the IMM 301, the electrode switches are shorted one by one to sequentially measure the ImpS of each electrode. When one electrode is shorted and a sine waveform voltage is applied to that electrode, the current flowing through that electrode flows into a wiring 405 and is detected as a voltage value by a detection resistor 406. The voltage signal resulting from this current is further amplified by a log amplifier (LogAmp) 408 via an operational amplifier 407 that is linearly amplified with an appropriate gain. The voltage at the output terminal 403 applied to the electrode is input to a micro control unit (hereinafter referred to as MCU) 410 via wiring 409 and is internally A / D converted. The MCU 410 sends a control signal 411 to the DDS 401 to sweep the frequency of the sine wave to be generated within a desired frequency range. The frequency at this time, the applied voltage from the output terminal 403, and the measured voltage resulting from the current flowing through the element are stored and calculated in a memory (not shown) in the MCU 410 and displayed on the display 303 as the ImpS measurement result.

[0022] 5A and 5B show an example of the measurement result of ImpS measured by the IMM 301 described with reference to the drawings of FIGS. 3 and 4 (when the thermostatic bath 111 is filled with the thermostatic water 209 of FIG. 2 to a predetermined water level and the liquid level in the reaction vessel 107 is sufficiently high). FIG. 5A is a diagram showing an example of the impedance profile of a normal piezoelectric element 201 measured in water. FIG. 5A shows ImpS for each of three electrodes of a normal piezoelectric element 201. FIG. 5B is a diagram showing an example of the impedance profile of a normal piezoelectric element 201 measured in water. FIG. 5B shows ImpS for each of three electrodes of an abnormal piezoelectric element.

[0023] As shown in FIG. 5A, ImpS of a normal piezoelectric element shows a uniform profile for both the absolute value |Z| (absolute value 501 of the impedance of a normal piezoelectric element measured in water) and the phase difference ΔZ (phase 502 of the impedance of a normal piezoelectric element in water) for all electrodes, and there is a frequency fmin at which the absolute value |Z| has a minimum value Zmin. However, as shown in FIG. 5B, for an abnormal piezoelectric element, the profiles of the absolute value |Z| (absolute value 503 of the impedance of an abnormal piezoelectric element in water) and the phase difference ΔZ (phase 504 of the impedance of an abnormal piezoelectric element in water) for all electrodes are not uniform, and the minimum value Zmin of the absolute value |Z| is not observed. In this embodiment, focusing on such a difference in ImpS between a normal piezoelectric element and an abnormal piezoelectric element, an algorithm for determining whether each electrode part (each electrode) is normal or abnormal is developed by the following method, and is implemented in the IMM 301 shown in FIG. 3 and FIG. 4.

[0024] FIG. 6A is a diagram showing an example of an impedance profile of a normal piezoelectric element measured in water. FIG. 6A shows the result of measuring ImpS of an electrode of a normal piezoelectric element similar to that of FIG. 5A. The electrode number is the i-th electrode of the piezoelectric element, and the minimum value of the absolute value |Z| is expressed as Z_i_min, and its frequency is expressed as f_i_min. Therefore, for example, if one electrode of one piezoelectric element is divided into 10 parts, 10 sets of minimum values ​​of the absolute value |Z| and their frequencies (Z_i_min, f_i_min, i=1, 2, . . . 10) can be obtained from the ImpS profile from one piezoelectric element. If ImpS is measured for each electrode of a sufficient number (several hundred or more) of normal piezoelectric elements in advance, the average values ​​of Z_i_min and f_i_min (numbers are assigned in order from the top electrode, i=1, 2, . . . 10) may differ from place to place. In this embodiment, 10 divided electrodes are used, but this is not limited to this, and the number of divided electrodes may be set appropriately. When the average value ±3σ (standard deviation) of the Z_i_min and f_i_min values ​​for each electrode obtained from a sufficient number of normal piezoelectric elements is plotted, a frequency distribution 701 (normal range) and a minimum impedance distribution 702 (normal range) for each electrode are obtained, as shown in Figures 7A and 7B. In this embodiment, this distribution is used as the population of the normal range, and the normality or abnormality of each electrode is judged based on whether the minimum value of the absolute value |Z| for each electrode of the subject to be judged (the piezoelectric element to be checked for normality or abnormality) and whether its frequency is within this normal range.

[0025] Fig. 7C is a diagram showing an example of the distribution of the resonance frequency for each segment of a piezoelectric element measured using the population shown in Fig. 7A as a normal population, and Fig. 7D is a diagram showing an example of the distribution of the minimum impedance for each segment of a piezoelectric element measured using the population shown in Fig. 7B as a normal population. Dots 703 and 704 plotted on normal ranges 701 and 702 for both electrodes of frequency and minimum impedance are the frequency and minimum impedance detected by ImpS of the piezoelectric element to be judged. In this example, the frequency and minimum impedance of the first to fourth segments (split electrodes) are both outside the normal range, indicating that the upper part of this piezoelectric element to be judged has some abnormal characteristics.

[0026] FIG. 6B is a diagram showing an example of an impedance profile of a normal piezoelectric element measured in air or in a state where the thermostatic bath is empty after the thermostatic water 209 in FIG. 2 is drained and the thermostatic bath 111 is empty, or in a state where the piezoelectric element and the stirring mechanism 109 are removed from the automatic chemical analysis device 1. Unlike the ImpS in FIG. 6A measured in water, the acoustic load due to water is low, so the minimum value of ImpS is lower. This minimum value of ImpS measured in air is the resonance point of the piezoelectric element in acoustic engineering, and its frequency is called the resonance frequency of the piezoelectric element alone. Therefore, to distinguish from the minimum value of ImpS measured in water and its frequency described above, it is expressed as Z_i_r, f_i_r (the subscript i is the number of the divided electrode, as in the case of underwater measurement). The normal population ranges of Z_i_r and f_i_r measured in air differ from Z_i_min and f_i_min measured in water even for the same piezoelectric element, so they must be defined separately using a sufficient number of normal piezoelectric elements.

[0027] Furthermore, even with the same piezoelectric element, distinct characteristics appear in the phase difference ΔZ when measured in air, unlike when measured underwater. In the phase difference at resonance measured in air, the electrical characteristics of a normal piezoelectric element transition from capacitive to inductive, so the phase difference is zero, as in 603. Whether or not there is such a zero transition in the phase difference of ImpS measured in air can also be used to determine the normality of the piezoelectric element.

[0028] Normally, when ImpS is measured in air like this, the characteristics of the piezoelectric element 201 can be measured more accurately with higher sensitivity than in water. However, as described above, this requires time and effort, such as draining the constant temperature water 209 from the constant temperature bath 111 and partially disassembling and removing the stirring mechanism 109 that performs ultrasonic non-contact stirring. Therefore, as a maintenance method using the IMM301, a flow determination algorithm shown in Figure 8 is implemented inside the IMM301.

[0029] Fig. 8 is a flow chart showing a maintenance method for an automatic chemical analyzer, and shows the process flow of the maintenance kit according to this embodiment. In the process flow shown in Fig. 8, a loop process is performed using the electrode number as a counter to sequentially measure each electrode and judge whether it is normal or abnormal.

[0030] 8, after starting, in step S101, the MCU 410 constituting the IMM 301 executes a loop process of the electrode number (denoted as seg in the drawing). Then, in step S102, the MCU 410 measures the ImpS of the seg-th electrode. In step S103, if the absolute value |Z| of the measured ImpS is large, for example, on the order of mega-ohms, it is determined that the measurement target has a continuity defect, and the electrode is determined to be NG due to the continuity defect. On the other hand, if there is no continuity defect, the process proceeds to step S104.

[0031] In step S104, if the absolute value |Z| is infinitesimally close to zero, the MCU 410 determines that the electrode is NG as being short-circuited due to poor connection, water leakage, etc. After the processes of steps S103 and S104, the subsequent process flow branches in step S105 based on the measurement conditions in air and in water set in advance by the measurer (operator) before the process flow starts.

[0032] First, as described above, when a measurement is performed in air, the phase difference becomes zero at the resonance frequency in a normal piezoelectric element (the electrical characteristics change from capacitive to inductive), so first, in step S106, it is determined whether the phase difference is zero at the resonance frequency in that electrode. If the phase difference is not zero in this process, this means that the piezoelectricity has disappeared, and the result is determined to be NG. Next, in step S107, it is determined whether or not the impedance Zr at the resonant frequency is within normal range 702 shown in Fig. 7B. If it is not within normal range 702, it is determined as NG. On the other hand, if it is within normal range 702, the process proceeds to step S108, where it is determined whether or not the resonant frequency fr at the resonant frequency is within normal range 701 shown in Fig. 7A. If it is not within normal range 701, it is determined as NG. On the other hand, if it is within normal range 701, it is determined that the seg-th segment (divided electrode) is normal, and the process returns to step S101, the electrode number is incremented by 1, and the above-mentioned process is repeated.

[0033] Next, when the measurement is performed underwater, the absolute value and phase profile of ImpS have lower sensitivity than in air, as shown in FIG. 6A. Also, since the measurement is performed underwater, it may be affected by the acoustic load of water and reflected waves from the surroundings. In step S109, the profile is filtered (smoothed), and then Z_min and f_min are detected. In steps S110 and S111, it is determined whether or not the values ​​are within the normal range, as in the case of measurement in air, and normality or abnormality is determined. If the determination result in step S111 is normal, the process returns to step S101, the electrode number is incremented by 1, and the above-mentioned process is repeated. If all the divided electrodes are normal through the loop process in step S101, it is determined that the piezoelectric element 201 is normal. On the other hand, if all the divided electrodes are not normal, that is, if some of the divided electrodes are abnormal, it is determined that the piezoelectric element 201 is abnormal.

[0034] By executing the above-described judgment process flow for each electrode (each divided electrode), it is possible to judge whether each electrode (each divided electrode) is normal or abnormal, and if an abnormality is determined, it is possible to estimate the cause of the abnormality.

[0035] As described above, according to this embodiment, it is possible to provide an automatic chemical analysis apparatus, a maintenance kit for an automatic chemical analysis apparatus, and a maintenance method for an automatic chemical analysis apparatus, which, even if a malfunction occurs in the automatic chemical analysis apparatus, enable the cause of the malfunction to be identified and addressed at the user's site without the need to recover the apparatus or parts.

[0036] Furthermore, if some kind of malfunction occurs in an automatic analyzer that employs a stirring method in which the electrode on one side of the piezoelectric element, which is the sound source that generates ultrasound, is divided and power is selected to supply power to that electrode to adjust the irradiation position from the sound source, then by using this embodiment, it is possible to determine at which position on the piezoelectric element the piezoelectricity of the divided electrode has been lost or damaged, and even to clarify whether there is anything wrong with the piezoelectric element itself, and other causes of the malfunction, such as the power amplifier that supplies power or the relay circuit that selects the electrode.

[0037] The present invention is not limited to the above-described embodiment, but includes various modified examples. For example, the above-described embodiment has been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to the embodiment having all of the described configurations. [Explanation of symbols]

[0038] 1…Automatic chemical analyzer 2. Maintenance kit 101...Sample cup 102...Sample disc 103…Reagent bottle 104…Reagent cooling disk 105...Sample dispenser 106...Reagent dispenser 107...Reaction vessel 108…Reaction disk 109...Mixing mechanism 110…Absorbance meter 111…Thermostatic oven 112…Connector 113...Power amplifier system 201...Piezoelectric element 202...Jig 205...Function generator circuit 206...Final stage amplifier circuit 207...Current monitor 208…Relay group 209…Constant temperature water 210...Electrode 211...Divided electrode 219…Signal from host computer 301…Maintenance kit body 302...Operation button 303...Indicator 304...Signal line (cable) 305…Connector 306…Connector 401...Digital Direct Synthesizer 402…Amplifier 403...Output terminal 404…Relay group 405…Wiring 406…Detection resistor 407…Op-amp 408…LogAmp 409…Wiring 410…Micro Control Unit (MCU) 411...Control signal

Claims

1. An automated chemical analyzer comprising: a reaction vessel capable of accommodating at least a dispensed specimen and a reagent; and a stirring mechanism having a piezoelectric element for irradiating ultrasonic waves to the reaction vessel, the piezoelectric element having a plurality of divided electrodes, an interface unit to which a relay circuit and a power amplifier system for driving the piezoelectric element can be connected; An automatic chemical analysis apparatus characterized in that a maintenance kit connectable to the interface unit is used to measure the absolute value of the impedance of the piezoelectric element and the phase difference between the voltage and current applied to the split electrodes for each split electrode, and the presence or absence of an abnormality in each split electrode is determined based on the measurement results.

2. 2. The automated chemical analyzer according to claim 1, The maintenance kit detects the frequency and absolute value of the impedance at which the absolute value of the impedance of the piezoelectric element is minimum for each of the divided electrodes, and determines whether or not each of the divided electrodes is abnormal.

3. 3. The automated chemical analyzer according to claim 2, The maintenance kit is an automatic chemical analysis apparatus characterized in that it determines whether or not each of the split electrodes has an abnormality by using a frequency at which the absolute value of the impedance of the piezoelectric element is minimum and a normal range of the absolute value of the impedance for each of the split electrodes that are preset in advance.

4. 4. The automated chemical analyzer according to claim 3, The maintenance kit is an automatic chemical analysis apparatus characterized in that it measures the impedance spectrum for each divided electrode of a large number of normal piezoelectric elements in advance, and sets, for each divided electrode, a frequency at which the absolute value of the impedance of the piezoelectric element is minimum and a normal range of the absolute value of the impedance based on the measured impedance spectrum.

5. 5. The automated chemical analyzer according to claim 4, The maintenance kit is an automatic chemical analysis apparatus characterized in that it measures the impedance spectrum of each divided electrode of a normal piezoelectric element under conditions in water and in air, and performs a smoothing process on the impedance spectrum measured in water to remove the effects of reflected waves received in a constant temperature bath.

6. A maintenance kit for an automatic chemical analyzer, comprising: a reaction vessel capable of accommodating a dispensed specimen and a reagent; and a stirring mechanism having a piezoelectric element for irradiating ultrasonic waves to the reaction vessel, the piezoelectric element having a plurality of split electrodes, the kit being connectable to an automatic chemical analyzer, A maintenance kit for an automatic chemical analysis apparatus, characterized in that the absolute value of the impedance of the piezoelectric element and the phase difference between the voltage and current applied to the split electrode are measured for each split electrode, and the presence or absence of an abnormality in each split electrode is determined based on the measurement results.

7. 7. The maintenance kit for an automatic chemical analyzer according to claim 6, A maintenance kit for an automatic chemical analyzer, characterized in that the frequency and absolute value of the impedance of the piezoelectric element at which the absolute value of the impedance is minimum for each of the divided electrodes are detected, and the presence or absence of an abnormality in each of the divided electrodes is determined.

8. 8. The maintenance kit for an automatic chemical analyzer according to claim 7, A maintenance kit for an automatic chemical analysis apparatus, characterized in that the presence or absence of an abnormality in each of the split electrodes is determined by using the frequency at which the absolute value of the impedance of the piezoelectric element is minimized and the normal range of the absolute value of the impedance for each of the split electrodes that are preset in advance.

9. 9. The maintenance kit for an automated chemical analyzer according to claim 8, A maintenance kit for an automatic chemical analyzer, characterized in that the impedance spectrum of each divided electrode of a large number of normal piezoelectric elements is measured in advance, and the frequency at which the absolute value of the impedance of the piezoelectric element is minimized and the normal range of the absolute value of the impedance are set for each divided electrode based on the measured impedance spectrum.

10. 9. The maintenance kit for an automated chemical analyzer according to claim 8, A maintenance kit for an automatic chemical analyzer, characterized in that the impedance spectrum of each divided electrode of a normal piezoelectric element is measured under conditions both in water and in air, and the impedance spectrum measured in water is smoothed to remove the effects of reflected waves received in a thermostatic chamber.

11. A maintenance method for an automated chemical analyzer comprising: a reaction vessel capable of accommodating at least a dispensed specimen and a reagent; and a stirring mechanism having a piezoelectric element for irradiating ultrasonic waves to the reaction vessel, the piezoelectric element having a plurality of divided electrodes, the method comprising the steps of: Connect the maintenance kit to an automatic chemical analyzer via the interface unit. A maintenance method for an automatic chemical analysis apparatus, characterized in that the maintenance kit measures the absolute value of the impedance of the piezoelectric element for each divided electrode and the phase difference between the voltage and current applied to the divided electrode, and determines whether or not each divided electrode is abnormal based on the measurement results.

12. The maintenance method for an automated chemical analyzer according to claim 11, A maintenance method for an automatic chemical analysis apparatus, characterized in that the maintenance kit detects the frequency and absolute value of the impedance at which the absolute value of the impedance of the piezoelectric element is minimum for each of the divided electrodes, and determines whether or not each of the divided electrodes is abnormal.

13. The maintenance method for an automated chemical analyzer according to claim 12, further comprising the steps of: The maintenance kit is a maintenance method for an automatic chemical analysis apparatus characterized in that it determines whether or not each of the split electrodes has an abnormality by using a frequency at which the absolute value of the impedance of the piezoelectric element is minimum and a normal range of the absolute value of the impedance for each of the split electrodes that are preset in advance.

14. The maintenance method for an automated chemical analyzer according to claim 13, The maintenance method for an automatic chemical analysis apparatus is characterized in that the maintenance kit measures the impedance spectrum for each divided electrode of a large number of normal piezoelectric elements in advance, and sets, for each divided electrode, a frequency at which the absolute value of the impedance of the piezoelectric element is minimum and a normal range of the absolute value of the impedance, based on the measured impedance spectrum.

15. The method for maintaining an automated chemical analyzer according to claim 14, further comprising the steps of: The maintenance kit is a maintenance method for an automatic chemical analysis apparatus, characterized in that the impedance spectrum of each divided electrode of a normal piezoelectric element is measured under conditions in water and in air, and the impedance spectrum measured in water is smoothed to remove the effects of reflected waves received in a thermostatic chamber.

Images