JP2012037236A - Dispensation apparatus, analyzer and liquid level detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dispensation apparatus capable of correctly detecting the liquid level of a liquid by discriminating a steep noise of static electricity and a signal in liquid level contact, an analyzer and a liquid level detection method.SOLUTION: A dispensation apparatus 12 includes: a storage section 35 for storing a voltage correction coefficient for each specimen and a voltage correction coefficient based on the kind of a container accommodating the specimen; an information reader for acquiring specimen information and container information; a calculation section 12u for calculating a threshold voltage on the basis of the voltage correction coefficient of the specimen and the voltage correction coefficient of the container which are extracted from the storage section 35; and a determination section 12t in which, when a signal received by a dispensation probe 12b outputs the threshold voltage for a predetermined period or longer, a liquid level detection is determined.

Description

  The present invention relates to a dispensing apparatus that dispenses a liquid after detecting a liquid level of a specimen or a reagent, an analyzer using the dispensing apparatus, and a liquid level detecting method.

  Conventionally, as an apparatus for automatically analyzing a sample such as blood or body fluid, an analyzer that adds a sample to a cuvette into which a reagent is dispensed and optically detects a reaction between the reagent and the sample in the cuvette. Are known. In such an analyzer, a liquid level detection device that detects the liquid level is used in order to perform an accurate dispensing process of a specimen and a reagent (see, for example, Patent Document 1). The liquid level detection device of Patent Document 1 receives a signal induced from an electrode connected to an oscillator by a dispensing probe that is a reception electrode, amplifies and rectifies the received signal, and outputs obtained by different time constants. A difference between input signals is obtained as an output signal as detection information by connecting to a comparator via a plurality of time constant circuits.

Japanese Patent Laid-Open No. 06-174551

  By the way, the liquid level detection device of Patent Document 1 receives a signal induced from an electrode connected to an oscillator by a reception electrode, but the reception electrode also receives noise caused by electrostatic discharge or the like generated in the analysis device. In some cases, the liquid level of the liquid was erroneously detected.

  The present invention has been made in view of the above, and in a liquid level detection mechanism based on a capacitance method, a dispensing device, an analysis device, and a device capable of correctly detecting a liquid level even when noise occurs An object of the present invention is to provide a liquid level detection method.

  In order to solve the above-described problems and achieve the object, a dispensing apparatus according to the present invention includes a dispensing probe that sucks or discharges a liquid that is conductive and stored in a container, and is integrated with the container. An electrode disposed in the vicinity of the container, and when the dispensing probe is lowered into the container while receiving a signal oscillated from an oscillator connected to the electrode by the dispensing probe. A dispensing apparatus including a liquid level detection mechanism that measures an output signal and detects a liquid level position of the liquid, and stores a voltage correction coefficient of a liquid to be dispensed and a voltage correction coefficient of a container that stores the liquid. Storage means, information acquisition means for acquiring liquid information including the type of liquid to be dispensed and container information for storing the liquid, and liquid information and container information of the liquid to be dispensed acquired by the information acquisition means And Extracting the voltage correction coefficient of the liquid and the voltage correction coefficient of the container from the storage means, calculating a threshold voltage for determining liquid contact based on the voltage correction coefficient, and receiving an output signal from the dispensing probe. Determining means for determining that the liquid level has been detected when the output signal outputs the threshold voltage calculated by the calculating means for a predetermined period or more.

  The dispensing apparatus of the present invention further comprises a signal processing circuit for performing signal processing including amplification and A / D conversion on the electrical signal output from the dispensing probe in the above invention, Liquid level detection is determined based on the output signal signal-processed by the signal processing circuit, and the storage means stores the electrical signal processed by the signal processing circuit for a predetermined period.

  Further, in the dispensing device of the present invention, in the above invention, the storage means stores an initial liquid level height corresponding to the type of the container, and a liquid level height of the liquid stored in each container, The calculating means calculates a threshold voltage based on a voltage correction coefficient corresponding to a liquid surface height stored in the container in addition to the voltage correction coefficient of the liquid and the voltage correction coefficient of the container.

  Moreover, the analyzer of the present invention is an analyzer that optically analyzes a reaction product between a specimen and a reagent, and dispenses the specimen and the reagent by using the dispensing apparatuses described above, respectively. Features.

  Further, the liquid level detection method of the present invention includes a dispensing probe that has conductivity and sucks or discharges a liquid contained in a container, an electrode disposed integrally with or in the vicinity of the container, The liquid level of the liquid is measured by measuring an output signal when the dispensing probe is lowered into the container while receiving a signal oscillated from an oscillator connected to the electrode by the dispensing probe. A liquid level detection method using a liquid level detection mechanism that detects liquid information including the type of liquid to be dispensed and information on a container that contains the liquid, and the dispensing acquired by the information acquisition step Based on the liquid information and the container information of the liquid to be extracted, the voltage correction coefficient of the liquid and the voltage correction coefficient of the container are extracted from the storage means, and a threshold voltage for determining the liquid contact is calculated based on the voltage correction coefficient. And a determination step of receiving an output signal from the dispensing probe and determining that the liquid level has been detected when the output signal outputs the threshold voltage calculated by the calculation step for a predetermined period or longer. It is characterized by including.

  In the liquid level detection method of the present invention, in the above invention, the output signal from the pipetting probe is subjected to signal processing including amplification and A / D conversion, and the output processed in the signal processing step. Storing the signal for a predetermined period of time, wherein the determining step determines liquid level detection based on the output signal signal-processed by the signal processing step.

  Moreover, the liquid level detection method of the present invention includes a liquid level storage step of storing the liquid level height of the liquid stored in each container after the end of dispensing in the above invention, wherein the calculation step includes In addition to the voltage correction coefficient and the voltage correction coefficient of the container, the threshold voltage is calculated based on a voltage correction coefficient corresponding to the liquid level contained in the container.

  The present invention stores a voltage correction coefficient of a liquid to be dispensed and a voltage correction coefficient of a container containing the liquid, calculates a threshold voltage based on the voltage correction coefficient, and calculates the threshold voltage. Since the liquid level detection is determined based on the above, it is possible to accurately discriminate between steep noise such as static electricity and the liquid level of the liquid.

(Embodiment 1)
Hereinafter, with reference to the drawings, as an embodiment of the present invention, an analyzer having a dispensing device for dispensing a liquid sample or reagent such as blood or urine will be described as an example. Note that the present invention is not limited to the embodiments. In the description of the drawings, the same parts are denoted by the same reference numerals.

  FIG. 1 is a schematic diagram illustrating the configuration of the analyzer according to the first embodiment. As shown in FIG. 1, the analyzer 1 according to the first embodiment dispenses a sample and a reagent to be analyzed to a cuvette 21 and optically measures a reaction occurring in the dispensed cuvette 21. A mechanism 2 and a control mechanism 3 that controls the entire analyzer 1 including the measurement mechanism 2 and analyzes the measurement result in the measurement mechanism 2 are provided. The analyzer 1 automatically performs biochemical analysis of a plurality of specimens through the cooperation of these two mechanisms. The cuvette 21 is a very small container having a capacity of several nL to several mL, and is a transparent material that transmits 80% or more of the light contained in the analysis light (340 to 800 nm) emitted from the light source of the photometry unit 18; For example, glass including heat-resistant glass, synthetic resins such as cyclic olefin and polystyrene are used.

  First, the measurement mechanism 2 will be described. The measurement mechanism 2 roughly includes a sample transfer unit 11, a sample dispensing device 12, a reaction table 13, a reagent storage 14, a reagent dispensing device 16, a stirring unit 17, a photometric unit 18, and a cleaning unit 19.

  The sample transfer device 11 includes a plurality of sample racks 11b that hold a plurality of sample containers 11a that store liquid samples such as blood and urine and sequentially transfer them in the direction of the arrows in the figure. The sample in the sample container 11a transferred to a predetermined position on the sample transfer unit 11 is dispensed by the sample dispensing device 12 into the cuvette 21 that is arranged and transported on the reaction table 13. The sample transport unit 11 includes an information reading device 11c that reads information from an information storage medium attached to the sample container 11a. This information storage medium is a bar code symbol that displays various types of encoded information and is optically read, and transmits reagent information stored via radio waves of a predetermined frequency and rewrites stored reagent information. It may be an RFID tag. The information reading device 11 c reads the sample information and the type of the sample container 11 a that stores the sample from the information storage medium, and outputs them to the control unit 31. The information reading device 11c reads information on the information storage medium by emitting infrared light or visible light to the information storage medium and processing the reflected light from the information storage medium. In addition, the information reading device 11c may acquire information on the storage medium by performing an imaging process on the information storage medium and decoding image information obtained by the imaging process. Further, the information reading device 11c may read information on the storage medium and rewrite information on the storage medium via radio waves having a predetermined frequency.

  As shown in FIG. 2, the sample dispensing apparatus 12 includes a dispensing probe 12b made of a conductive metal material such as stainless steel, an electrode 12x for installing a sample container 11a containing a sample, a syringe pump 12h, an electromagnetic valve 12k, and a pump. 12m, a cleaning liquid tank 12n, a voltage detection circuit 12p, an amplification circuit 12q, an A / D converter 12r, and a dispensing control unit 12o.

  The dispensing probe 12b is supported by an arm 12a that freely moves up and down in the vertical direction and rotates around the vertical line passing through its base end, and moves up and down or rotates the arm 12a by the probe driving unit 12d. As a result, the sample in the sample container 11a containing the sample is sucked by the dispensing probe 12b and discharged to the cuvette 21 at a predetermined position, thereby dispensing the sample.

  The syringe pump 12h has a cylinder 12f and a piston 12g, and is connected to the dispensing probe 12b by a pipe 12e. The syringe pump 12h is driven by the piston drive unit 12i, and the piston 12g slides in the vertical direction inside the cylinder 12f to suck or discharge the specimen to the dispensing probe 12b via the push liquid L1. To transmit the pressure.

  The electromagnetic valve 12k is an electromagnetic valve connected to the syringe pump 12h by the pipe 12j and the cleaning liquid tank 12n via the pump 12m by the pipe 12l and switched by the dispensing control unit 12o. The cleaning liquid tank 12n contains an extrusion liquid L made of an incompressible fluid such as degassed water, ion exchange water or distilled water.

  An AC signal having a predetermined frequency oscillated by an oscillator 12s that operates under the control of the dispensing control unit 12o is applied to the electrode 12x. The alternating current signal oscillated from the oscillator 12s is received by the dispensing probe 12b through the electrode 12x, and is output to the voltage detection circuit 12p including the capacitor 12v and the resistor 12w. The voltage detection circuit 12p detects a voltage signal (analog) and outputs it to the amplification circuit 12q. The amplifier circuit 12q amplifies the voltage signal (analog) output from the voltage detection circuit 12p, and outputs the amplified pressure signal to the A / D converter 12r. The A / D converter 12r converts the voltage signal (analog) input from the amplifier circuit 12q into a digital signal, and then outputs the voltage signal (digital) to the dispensing control unit 12o.

The dispensing control unit 12o is a control unit that controls the operation of the probe driving unit 12d, the piston driving unit 12i, the electromagnetic valve 12k, the pump 12m, and the oscillator 12s, and is configured using a CPU, RAM, ROM, or the like. The dispensing control unit 12o includes a determination unit 12t and a calculation unit 12u. The calculation unit 12u uses the sample information and the container information acquired from the information storage medium attached to the sample container 11a by the information reading device 11c shown in FIG. 1, and the voltage correction coefficient and the container of the sample extracted from the storage unit 35 The threshold voltage for determining the liquid contact is calculated based on the voltage correction coefficient. The determination unit 12t receives the output signal from the dispensing probe 12b, and determines that the liquid level is detected when the output signal outputs the threshold voltage calculated by the calculation unit 12u for a predetermined period or more. The storage unit 35 stores voltage correction coefficients for the sample type and the sample container type. As illustrated in FIGS. 3 and 4, the voltage correction coefficient is stored in the storage unit 35 in association with the type of specimen and the type of specimen container. The control unit 31 to be described later extracts the voltage correction coefficient of the sample to be dispensed and the container by referring to FIGS. 3 and 4 stored in the storage unit 35. FIG. 5 is a diagram showing the relationship between the position of the dispensing probe 12b and the output voltage in the sample dispensing apparatus 12 of FIG. As shown in FIG. 5, the voltage signal detected by the voltage detection circuit 12p increases as the dispensing probe 12b is lowered and approaches the sample stored in the sample container 11a, and the dispensing probe 12b contacts the liquid surface. The reached voltage is reached at h ₁ . Since this ultimate voltage varies depending on the type of specimen and the material and shape of the specimen container 11a, the calculation unit 12u calculates the ultimate voltage and its threshold voltage based on the extracted specimen voltage correction coefficient and container voltage correction coefficient. .

  FIG. 6 is a diagram showing the relationship between the time and the output voltage when the dispensing probe 12b is lowered into the sample container 11a. The calculation unit 12u calculates the ultimate voltage V1 and the threshold voltage V1 'based on the extracted voltage correction coefficient of the specimen and the voltage correction coefficient of the container. The determination unit 12t determines that the liquid level has been detected when the output voltage outputs the threshold voltage V1 'calculated by the calculation unit 12u for a predetermined period (ΔTh) or more (at t4). Thereby, for example, noise due to static electricity or the like generated at t1 to t2 as shown in FIG. 6 is not output more than the threshold voltage V1 ′ for a predetermined period (ΔTh) or more, so the determination unit 12t outputs the output voltage at t1 to t2. This change is not determined as the liquid level detection, and it is possible to determine when the liquid level is in contact (t3 to t4).

  The reaction table 13 transfers the cuvette 21 to a predetermined position in order to perform dispensing of a sample or a reagent to the cuvette 21, agitation of the cuvette 21, photometry, washing, and photometry for contamination detection. The reaction table 13 is rotatable about a vertical line passing through the center of the reaction table 13 as a rotation axis by driving a drive mechanism (not shown) under the control of the control unit 31. An openable and closable lid and a thermostat (not shown) are provided above and below the reaction table 13, respectively.

  The reagent store 14 can store a plurality of reagent containers 15 holding reagents to be dispensed in the cuvette 21. In the reagent store 14, a plurality of storage chambers are arranged at equal intervals, and a reagent container 15 is detachably stored in each storage chamber. The reagent storage 14 can be rotated clockwise or counterclockwise about a vertical line passing through the center of the reagent storage 14 as a rotation axis by driving a drive mechanism (not shown) under the control of the control unit 31. A desired reagent container 15 is transferred to a reagent suction position by the reagent dispensing device 16. An openable / closable lid (not shown) is provided above the reagent storage 14. In addition, the reagent store 14 has a cooling function, and when the reagent container 15 is housed and the lid is closed, the reagent store 14 cools the reagent held in the reagent container 15 and evaporates the reagent. And suppress denaturation.

  An information storage medium in which reagent information related to the reagent held in the reagent container 15 is recorded is attached to the side surface of the reagent container 15. For example, the information storage medium stores analysis items in which the reagent held in the reagent container 15 is used, reagent name, reagent information such as lot information, and reagent container information. This information storage medium is a bar code symbol that displays various types of encoded information and is optically read, and transmits reagent information stored via radio waves of a predetermined frequency and rewrites stored reagent information. It may be an RFID tag.

  An information reading device 14 a that reads this storage medium is provided on the outer periphery of the reagent storage 14. The information reading device 14 a reads the reagent information and the type of the reagent container 115 that stores the reagent from the information storage medium, and outputs them to the control unit 31. The information reading device 14a emits infrared light or visible light to the information storage medium and processes the reflected light from the information storage medium to read the information on the information storage medium. Further, the information reading device 14a may acquire information of the storage medium by performing an imaging process on the information storage medium and decoding image information obtained by the imaging process. In addition, the information reading device 14a may read information on the storage medium and rewrite information on the storage medium via radio waves having a predetermined frequency. The information reading device 14a outputs the read information of the storage medium to the control unit 31 in association with the position in the reagent storage 14 of the reagent container 15 to which the storage medium is attached.

  As shown in FIG. 7, the reagent dispensing device 16 includes a dispensing probe 16b made of a conductive metal material such as stainless steel, an electrode plate 16 on which a reagent container 15 containing a reagent is installed, a syringe pump 16h, a solenoid valve 16k, A pump 16m, a cleaning liquid tank 16n, a voltage detection circuit 16p, an amplification circuit 16q, an A / D converter 16r, and a dispensing control unit 16o are provided, and in the same manner as the sample dispensing apparatus 12 described above, the reagent in the reagent container 15 Detect the liquid level and dispense the reagent.

  The dispensing control unit 16o includes a determination unit 16t and a calculation unit 16u. The calculation unit 16u uses the reagent information and the container information acquired from the information storage medium attached to the reagent container 15 by the information reading device 14a shown in FIG. 1, and the voltage correction coefficient of the reagent and the voltage correction of the container from the storage unit 35. A coefficient is extracted, and a threshold voltage for determining liquid contact is calculated based on the voltage correction coefficient. The determination unit 16t receives the output signal from the dispensing probe 16b, and determines that the liquid level has been detected when the output signal outputs the threshold voltage calculated by the calculation unit 16u for a predetermined period or more. The storage unit 35 stores the voltage correction coefficient for the reagent type and the voltage correction coefficient for the reagent container type. As illustrated in FIGS. 8 and 9, the voltage correction coefficient is stored in the storage unit 35 in association with the reagent type and the reagent container type. The control unit 31 described later extracts the voltage correction coefficient of the reagent to be dispensed and the voltage correction coefficient of the container by referring to FIGS. 8 and 9 stored in the storage unit 35, and the calculation unit 16u A threshold voltage is calculated based on the voltage correction coefficient.

  The agitating unit 17 agitates the sample dispensed in the cuvette 21 and the reagent to promote the reaction. For example, the photometry unit 18 irradiates the cuvette 21 transported to a predetermined photometry position with analysis light (340 to 800 nm) from a light source, disperses the light transmitted through the liquid in the cuvette 21, and uses a light receiving element such as a PDA. By measuring the intensity of each wavelength light, the absorbance at a wavelength peculiar to the reaction solution of the sample to be analyzed and the reagent is measured.

  The cleaning unit 19 sucks and discharges the mixed liquid in the cuvette 21 that has been measured by the photometry unit 18 by the cleaning nozzle, and completes the analysis process by injecting and sucking cleaning liquid such as detergent and cleaning water. The cuvette 21 is washed.

  Next, the control mechanism 3 will be described. The control mechanism 3 includes a control unit 31, an input unit 32, an analysis unit 33, a storage unit 35, and an output unit 36. These units included in the measurement mechanism 2 and the control mechanism 3 are electrically connected to the control unit 31.

  The control unit 31 is configured using a CPU or the like, and controls processing and operation of each unit of the analyzer 1. The control unit 31 performs predetermined input / output control on information input / output to / from each of these components, and performs predetermined information processing on this information.

  The input unit 32 is configured using a keyboard, a mouse, and the like, and acquires various information necessary for analyzing the sample, instruction information for analysis operation, and the like from the outside. The analysis unit 33 performs component analysis of the specimen based on the absorbance measured by the photometry unit 18.

  The storage unit 35 is configured using a hard disk that magnetically stores information and a memory that loads various programs related to the process from the hard disk and electrically stores them when the analyzer 1 executes the process. Various information including the analysis result of the sample is stored. The storage unit 35 may include an auxiliary storage device that can read information stored in a storage medium such as a CD-ROM, a DVD-ROM, or a PC card. The storage unit 35 stores the voltage correction coefficient of the sample type to be dispensed by the sample dispensing apparatus 12 or the reagent dispensing apparatus 16, the voltage correction coefficient of the reagent type, and the voltage correction coefficient of each container that stores the sample or reagent. . The storage unit 35 is a voltage signal amplified by the amplifier circuits 12q and 16q, analog / digital converted by the A / D converters 12r and 16r, and output via the dispensing control units 12o and 16o and the control unit 31. Is stored for a predetermined period. By storing and storing the output signal in the storage unit 35 for a predetermined period, when a malfunction occurs in the liquid level detection mechanism, the cause of the malfunction can be analyzed based on the stored output signal, so that the cause of the malfunction can be easily determined. .

  The output unit 36 is configured using a display, a printer, a speaker, and the like, and outputs various information including the analysis result of the sample. The output unit 36 also outputs various information to an external device via a communication network (not shown).

  In the analyzer 1 configured as described above, the sample dispensing device 12 dispenses the sample in the sample container 11a to the plurality of cuvettes 21 that are sequentially conveyed in a row, and the reagent dispensing device 16 After dispensing the reagent in the reagent container 15, the photometric unit 18 measures the spectral intensity of the sample in a state where the sample and the reagent are reacted, and the analysis unit 33 analyzes the measurement result, Component analysis and the like are automatically performed. In addition, the cleaning unit 19 performs cleaning while transporting the cuvette 21 transported after the measurement by the photometry unit 18 is completed, so that a series of analysis operations are continuously repeated.

  Next, the sample dispensing process in the sample dispensing apparatus 12 will be described. FIG. 10 is a flowchart showing the processing procedure of the sample dispensing process in the sample dispensing apparatus 12 shown in FIG. As shown in FIG. 10, first, the information reading device 11c reads the sample information and the container information from the information storage medium attached to the sample container 11a of the sample to be dispensed (step S100). Subsequently, the control unit 31 extracts the voltage correction coefficient of the sample and the voltage correction coefficient of the container from the storage unit 35 based on the sample information and the container information read by the information reading device 11c (Step S101), and extracts the extracted voltage. Based on the correction coefficient, the calculation unit 12u calculates a threshold voltage at the time of liquid contact (step S102). Thereafter, the dispensing probe 12b is lowered into the sample container 11a by the probe driving unit 12d (step S103). As the dispensing probe 12b is lowered, the oscillator 12s oscillates an AC signal having a predetermined frequency under the control of the dispensing controller 12o, and the signal received by the dispensing probe 12b is a voltage signal (analog) by the voltage detection circuit 12p. Is detected and acquired (step S104). The acquired voltage signal (analog) is amplified by the amplifier circuit 12q and then converted to a digital signal by the A / D converter 12r (step S105). The converted voltage signal (digital) is stored in the storage unit 35 for a predetermined period.

  Thereafter, the determination unit 12t compares the voltage signal (digital) with the threshold voltage calculated by the calculation unit 12u, and determines whether or not the output voltage is equal to or higher than the threshold voltage (step S106). When the output voltage is equal to or higher than the threshold voltage (step S106: Yes), it is confirmed whether or not the output voltage has output the threshold voltage for a predetermined period or longer (step S107). When the output voltage is not equal to or higher than the threshold voltage (step S106: No) and when the output voltage does not output the threshold voltage for a predetermined period or longer (step S107: No), the dispensing probe 12b is continuously lowered to acquire the output signal. The determination is continued (steps S103 to S106).

  When the output voltage is equal to or higher than the threshold voltage and output for a predetermined period or longer (step S107: Yes), the determination unit 12t determines that the dispensing probe 12b is in contact with the sample liquid surface, that is, detects the liquid surface, and dispense control is performed. A liquid level detection signal is output to the unit 12o (step S108). The dispensing control unit 12o that has received the liquid level detection signal controls to stop the lowering of the dispensing probe 12b by the probe driving unit 12d (step S109), and drives the syringe pump 12h via the piston driving unit 12i. After the sample is aspirated by the dispensing probe 12b (step S110), the sample is discharged to the cuvette 21 (step S111), and the dispensing probe 12b is washed in a washing tank (not shown) (step S112). Thereafter, the control unit 31 confirms whether or not the dispensing of all the samples has been completed (step S113). If the dispensing has been completed (step S113: Yes), the sample dispensing process has been completed and has not been completed. (Step S113: No) is repeated from Step S100.

  In the sample dispensing apparatus 12 according to the first embodiment, the calculation unit 12u calculates a threshold voltage based on the voltage correction coefficient of the sample and the voltage correction coefficient of the container, and the liquid level based on the threshold voltage calculated by the determination unit 12t. By determining whether or not the liquid level is detected, it is possible to prevent erroneous detection of the liquid level due to steep noise caused by static electricity or the like generated during sample dispensing. Also in the reagent dispensing apparatus 16, by performing the reagent dispensing process in the same manner as the flowchart shown in FIG. 10 described above, liquid level erroneous detection due to steep noise due to static electricity or the like generated during reagent dispensing is similarly performed. Can be prevented.

(Embodiment 2)
In the second embodiment, when calculating the threshold voltage, in addition to the voltage correction coefficient of the sample or the voltage correction coefficient of the reagent, and the voltage correction coefficient based on the container type, the height of the sample liquid stored in the sample container or the reagent container Alternatively, the liquid level is detected by calculating a threshold voltage based on a voltage correction coefficient corresponding to the reagent liquid level.

  FIG. 11 is a diagram showing the relationship between the position of the dispensing probe 12b and the output voltage in the sample dispensing apparatus of FIG. As shown in FIG. 11, even when the same kind of specimen (plasma) is contained in the same kind of specimen container (A), it is confirmed that the ultimate voltage at the time of specimen contact differs depending on the amount of specimen liquid. ing. Therefore, in the second embodiment, the calculation units 12u and 16u perform voltage correction according to the liquid level in the container in addition to the voltage correction coefficient of the specimen or the correction coefficient of the reagent and the voltage correction coefficient based on the container type. A threshold voltage is calculated based on the coefficient, and the determination units 12t and 16t determine the liquid level based on the threshold voltage.

First, the sample dispensing process in the sample dispensing apparatus 12 of the second embodiment will be described. FIG. 12 is a flowchart showing the processing procedure of the sample dispensing process in the second embodiment. As shown in FIG. 12, first, the information reading device 11c reads the sample information and the container information from the information storage medium attached to the sample container 11a of the sample to be dispensed (step S200). Subsequently, based on the sample information and the container information read by the information reading device 11c, the control unit 31 calculates the voltage correction coefficient of the sample and the voltage correction coefficient of the container together with the analysis item information of the sample dispensed from the storage unit 35. Extract (step S201). Thereafter, the control unit 31 checks whether or not the sample to be dispensed is dispensed for the first analysis item based on the analysis item information extracted for the sample to be dispensed (step S202). When the dispensing is for the first analysis item (step S202: Yes), the maximum liquid level height H based on the type of the specimen container in which the specimen is accommodated is extracted from the storage unit 35, and the voltage correction coefficient is acquired ( Step S203). In addition to the voltage correction coefficient illustrated in FIGS. 3 and 4 described in the first embodiment, the storage unit 35 stores the maximum liquid level for each sample container type. The sample container has various shapes (see FIG. 13), and the maximum liquid level height (H _{A to} H _E ) for storing the sample is specified by the size of the sample container. In the storage unit 35, the maximum liquid level height (see FIG. 14) corresponding to the type of the specimen container and the function of the liquid level height and the voltage correction coefficient (see FIG. 15) are stored for each specimen container. A voltage correction coefficient based on the maximum liquid level of the sample container in which the sample to be dispensed is stored is acquired.

  On the other hand, when the sample to be dispensed is not dispensed for the first analysis item (step S202: No), the control unit 31 calculates the liquid level height of the sample contained in the sample container 11a calculated in step S214 described later. Is acquired (step S204). Thereafter, the calculation unit 12u calculates a threshold voltage based on the voltage correction coefficient corresponding to the liquid level acquired in step S203 or step S204, the voltage correction coefficient of the specimen and the voltage correction coefficient of the container acquired in step S201. (Step S205). Thereafter, under the control of the dispensing control unit 12o, the probe driving unit 12d lowers the dispensing probe 12b into the sample container 11a (step S206). As the dispensing probe 12b is lowered, the oscillator 12s oscillates an AC signal having a predetermined frequency under the control of the dispensing controller 12o, and the signal received by the dispensing probe 12b is converted into a voltage signal (analog) by the voltage detection circuit 12p. It is detected and acquired (step S207). The acquired voltage signal (analog) is amplified by the amplifier circuit 12q and then converted to a digital signal by the A / D converter 12r (step S208). The converted voltage signal (digital) is stored in the storage unit 35 for a predetermined period.

  Thereafter, the determination unit 12t compares the voltage signal (digital) with the threshold voltage calculated by the calculation unit 12u, and determines whether or not the output voltage is equal to or higher than the threshold voltage (step S209). When the output voltage is equal to or higher than the threshold voltage (step S209: Yes), it is confirmed whether or not the output voltage has output the threshold voltage for a predetermined period or longer (step S210). When the output voltage is not equal to or higher than the threshold voltage (step S209: No), and when the output voltage does not output the threshold voltage for a predetermined period or longer (step S210: No), the dispensing probe 12b is continuously lowered to acquire the output signal. The determination is continued (steps S206 to S209).

  When the output voltage outputs the threshold voltage for a predetermined period or longer (step S210: Yes), the determination unit 12t determines that the dispensing probe 12b is in contact with the sample liquid surface, that is, the liquid level is detected, and the liquid is supplied to the dispensing control unit 12o. A surface detection signal is output (step S211). Receiving the liquid level detection signal, the dispensing control unit 12o controls to stop the descent of the dispensing probe 12b by the probe driving unit 12d (step S212), and drives the syringe pump 12h via the piston driving unit 12i. The sample is aspirated by the dispensing probe 12b (step S213). After the completion of dispensing, the calculation unit 12u calculates the liquid level height after the sample aspiration based on the liquid level determined to be the liquid level detection in step S211 and the dispensed sample amount (step S214). The calculated liquid level is temporarily stored in the storage unit 35 until dispensing of all analysis items of the sample is completed (step S215). Thereafter, the aspirated specimen is discharged to the cuvette 21 (step S216), and the dispensing probe 12b is washed in a washing tank (not shown) (step S217). The control unit 31 confirms whether or not the sample dispensing is the last dispensing of the same sample (step S218), and if it is not the last dispensing of the same sample (step S218: No), the sample dispensing process is performed. It repeats from step S204. On the other hand, when it is the last dispensing (step S218: Yes), the control unit 31 confirms whether dispensing of all the samples is completed (step S219), and dispensing of all the samples is completed. If yes (step S219: Yes), the sample dispensing process ends. If not (step S219: No), the sample dispensing process is repeated from step S200.

  Next, the reagent dispensing process in the reagent dispensing apparatus 16 of the second embodiment will be described. FIG. 16 is a flowchart showing the procedure of the reagent dispensing process in the second embodiment. As shown in FIG. 16, first, the information reading device 14a obtains reagent information and container information from the position in the reagent storage 14 of the reagent to be dispensed and the information storage medium attached to the reagent container 15 containing the reagent. Read (step S300). Subsequently, the control unit 31 reads the reagent voltage correction coefficient, the container voltage correction coefficient, and the reagent liquid level height from the storage unit 35 based on the reagent position, reagent information, and container information read by the information reading device 14a. A voltage correction coefficient corresponding to the above is acquired (step S301). In addition to the voltage correction coefficient illustrated in FIGS. 8 and 9 described in the first embodiment, the storage unit 35 stores the reagent liquid level height. As illustrated in FIG. 17, for each position in the reagent storage 14, the type of reagent to be held, the type of reagent container of the reagent, and the initial liquid level of the reagent container are stored, and reagent dispensing from the reagent container is performed. After being performed, the reagent liquid level calculated in step S311 described later is also stored. The storage unit 35 also stores the function of the liquid level and the voltage correction coefficient (see FIG. 18) for each reagent container, and the control unit 31 is based on the reagent information and container information read by the information reading device 14a. The voltage correction coefficient based on the liquid level of the reagent to be dispensed is acquired.

  Based on the acquired reagent voltage correction coefficient, container voltage correction coefficient, and voltage correction coefficient based on the reagent liquid level, the calculation unit 16u calculates a threshold voltage (step S302). Thereafter, under the control of the dispensing control unit 16o, the probe driving unit 16d lowers the dispensing probe 16b into the reagent container 15 (step S303). As the dispensing probe 16b is lowered, the oscillator 16s oscillates an AC signal having a predetermined frequency under the control of the dispensing controller 16o, and the signal received by the dispensing probe 16b is converted into a voltage signal (analog) by the voltage detection circuit 16p. It is detected and acquired (step S304). The acquired voltage signal (analog) is amplified by the amplifier circuit 16q and then converted to a digital signal by the A / D converter 16r (step S305). The converted voltage signal (digital) is stored in the storage unit 35 for a predetermined period.

  Thereafter, the determination unit 16t compares the voltage signal (digital) with the threshold voltage calculated by the calculation unit 16u, and determines whether or not the output voltage is equal to or higher than the threshold voltage (step S306). When the output voltage is equal to or higher than the threshold voltage (step S306: Yes), it is confirmed whether or not the output voltage has output the threshold voltage for a predetermined period or longer (step S307). When the output voltage is not equal to or higher than the threshold voltage (step S306: No) and when the output voltage does not output the threshold voltage for a predetermined period or longer (step S307: No), the dispensing probe 16b is continuously lowered to acquire the output signal. The determination is continued (steps S303 to S306).

  When the output voltage is equal to or higher than the threshold voltage and output for a predetermined period or longer (step S307: Yes), the determination unit 16t determines that the dispensing probe 16b is in contact with the sample liquid surface, that is, detects the liquid surface, and dispense control is performed. A liquid level detection signal is output to the unit 16o (step S308). Receiving the liquid level detection signal, the dispensing control unit 16o controls to stop the descent of the dispensing probe 16b by the probe driving unit 16d (step S309), and drives the syringe pump 16h via the piston driving unit 16i. The reagent is aspirated by the dispensing probe 16b (step S310). After the completion of dispensing, the calculating unit 16u calculates the liquid level height after the reagent aspiration based on the liquid level determined to be the liquid level detection in step S308 and the dispensed reagent amount (step S311). The calculated liquid level is stored in the storage unit 35 (step S312). Thereafter, the aspirated reagent is discharged to the cuvette 21 (step S313), and the dispensing probe 16b is washed in a washing tank (not shown) (step S314). The control unit 31 confirms whether or not all dispensing has been completed (step S315). If all dispensing has been completed (step S315: Yes), the reagent dispensing process is completed and terminated. If not (step S315: No), the reagent dispensing process is repeated from step S300.

  In the specimen dispensing apparatus 12 and the reagent dispensing apparatus 16 according to the second embodiment, the specimen liquid level height or the reagent liquid is provided together with the voltage correction coefficient of each specimen or the voltage correction coefficient of each reagent and the voltage correction coefficient based on the container type. The calculation unit 12u or 16u calculates the threshold voltage based on the voltage correction coefficient corresponding to the surface height, and the determination unit 12t or 16t determines whether the liquid level is based on the calculated threshold voltage. It is possible to prevent liquid level erroneous detection due to steep noise due to static electricity generated during dispensing more precisely.

1 is a schematic diagram illustrating a configuration of an analyzer according to a first embodiment. It is a figure explaining the principal part of the sample dispensing apparatus of Embodiment 1. FIG. 3 is a diagram illustrating an example of information stored in a storage unit according to Embodiment 1. FIG. 3 is a diagram illustrating an example of information stored in a storage unit according to Embodiment 1. FIG. It is a figure which shows the relationship between the dispensing probe position and output voltage in the sample dispensing apparatus of FIG. It is a figure which shows the relationship between the time and output voltage in the sample dispensing apparatus of FIG. It is a figure explaining the principal part of the reagent dispensing apparatus of Embodiment 1. FIG. 3 is a diagram illustrating an example of information stored in a storage unit according to Embodiment 1. FIG. 3 is a diagram illustrating an example of information stored in a storage unit according to Embodiment 1. FIG. 5 is a flowchart showing a processing procedure for sample dispensing processing in the first embodiment. It is a figure which shows the relationship between the dispensing probe position and output voltage in the sample dispensing apparatus of FIG. 12 is a flowchart showing a processing procedure for sample dispensing processing in the second embodiment. It is a figure explaining the sample container classification and the maximum sample amount accommodated in this. 6 is a diagram illustrating an example of information stored in a storage unit according to Embodiment 2. FIG. 6 is a diagram illustrating an example of information stored in a storage unit according to Embodiment 2. FIG. 12 is a flowchart showing a processing procedure for reagent dispensing processing in the second embodiment. 6 is a diagram illustrating an example of information stored in a storage unit according to Embodiment 2. FIG. 6 is a diagram illustrating an example of information stored in a storage unit according to Embodiment 2. FIG.

DESCRIPTION OF SYMBOLS 1 Analyzer 2 Measurement mechanism 3 Control mechanism 11 Specimen transfer part 11a Specimen container 11b Specimen rack 11c, 14a Information reader 12 Specimen dispenser 12a, 16a Arm 12b, 16b Dispensing probe 12c, 16c Prop 12d, 16d Probe drive part 12e, 12j, 12l, 16e, 16j, 16l Piping 12h, 16h Syringe pump 12i, 16i Piston drive unit 12k, 16k Solenoid valve 12m, 16m Pump 12n, 16n Cleaning liquid tank 12o, 16o Dispensing control unit 12p, 16p Voltage detection circuit 12q, 16q Amplifying circuit 12r, 16r A / D converter 12t, 16t Determination unit 12u, 16u Calculation unit 12s, 16s Oscillator 12x, 16x Electrode 12z, 16z Liquid level detection mechanism 13 Reaction table 14 Reagent storage 15 Reagent container 16 Trial Medicine dispensing device 17 Stirring unit 18 Photometry unit 19 Washing unit 21 Cuvette 31 Control unit 32 Input unit 33 Analysis unit 35 Storage unit 36 Output unit

Claims (7)

A dispenser probe that sucks or discharges the liquid contained in the container and having conductivity, and an electrode disposed integrally with the container or in the vicinity of the container, and from an oscillator connected to the electrode Dispensing provided with a liquid level detection mechanism for detecting the liquid level position of the liquid by measuring an output signal when the dispensing probe is lowered into the container while receiving the oscillated signal by the dispensing probe. A device,
Storage means for storing a voltage correction coefficient of a liquid to be dispensed and a voltage correction coefficient of a container containing the liquid;
Information acquisition means for acquiring liquid information including the type of liquid to be dispensed and container information for storing the liquid;
Based on the liquid information and container information of the liquid to be dispensed acquired by the information acquisition means, the voltage correction coefficient of the liquid and the voltage correction coefficient of the container are extracted from the storage means, and the liquid contact is performed based on the voltage correction coefficient. Calculating means for calculating a threshold voltage for determining
A determination unit that receives an output signal from the dispensing probe and determines that the liquid level has been detected when the output signal outputs a threshold voltage calculated by the calculation unit for a predetermined period or more;
A dispensing device comprising: A signal processing circuit for performing signal processing including amplification and A / D conversion on the output signal output from the dispensing probe, and the determination means is configured to detect the liquid level based on the output signal signal-processed by the signal processing circuit; Determine the detection,
The dispensing device according to claim 1, wherein the storage unit stores the electrical signal processed by the signal processing circuit for a predetermined period. The storage means stores the initial liquid level height according to the type of the container, and the liquid level height of the liquid stored in each container,
The calculation means calculates a threshold voltage based on a voltage correction coefficient in accordance with a liquid level contained in the container, in addition to the voltage correction coefficient of the liquid and the voltage correction coefficient of the container. The dispensing apparatus according to claim 1 or 2. In an analyzer that optically analyzes a reaction product between a sample and a reagent,
An analyzer characterized by dispensing a specimen and a reagent by using the dispensing apparatus according to any one of claims 1 to 3. A dispenser probe that sucks or discharges the liquid contained in the container and having conductivity, and an electrode disposed integrally with the container or in the vicinity of the container, and from an oscillator connected to the electrode A liquid level detection method using a liquid level detection mechanism that detects the liquid level of the liquid by measuring an output signal when the dispensing probe is lowered into the container while receiving the oscillated signal by the dispensing probe. Because
An information acquisition step for acquiring liquid information including the type of liquid to be dispensed and container information for storing the liquid;
Based on the liquid information and container information of the liquid to be dispensed acquired in the information acquisition step, the voltage correction coefficient of the liquid and the voltage correction coefficient of the container are extracted from the storage means, and the liquid contact is performed based on the voltage correction coefficient. A calculating step for calculating a threshold voltage to be determined;
A determination step of receiving an output signal from the dispensing probe and determining that a liquid level has been detected when the output signal outputs the threshold voltage calculated by the calculation step for a predetermined period; and
The liquid level detection method characterized by including. A signal processing step of subjecting the output signal from the dispensing probe to signal processing including amplification and A / D conversion;
A storage step for storing the output signal processed in the signal processing step for a predetermined period;
The liquid level detection method according to claim 5, wherein the determination step determines liquid level detection based on the output signal signal-processed by the signal processing step. A liquid level storing step for storing the liquid level height of the liquid stored in each container after the end of dispensing;
In the calculating step, the threshold voltage is calculated based on a voltage correction coefficient corresponding to a liquid level contained in the container in addition to the voltage correction coefficient of the liquid and the voltage correction coefficient of the container. The liquid level detection method according to claim 5 or 6.

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