JP2010286325A - Dispensing device, automatic analyzer and liquid level detection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dispensing device acquiring highly reliable analysis data by preventing erroneous detection of a liquid level and rapidly detecting the liquid level, an automatic analyzer and a liquid level detection method. <P>SOLUTION: A first reagent dispensing device 6 detects a change of a capacitance between a probe 6b for dispensing a reagent contained in a reagent vessel 2a and the reagent vessel 2a, and includes a liquid level detection part 6p for determining whether the lower end of the probe 6b is in contact with the liquid level of the reagent based on a detected signal. The first reagent dispensing device 6 includes a liquid level information storage part 6r storing liquid level information including the liquid level heights of liquids contained in each of a plurality of reagent vessels 2a for each reagent vessel 2a; a calculation part 6s for calculating an invalid time in which a signal transmitted from the liquid level detection part 6p is made invalid based on the liquid level information; and a liquid level detection signal control part 6t for making a liquid level detection signal from the liquid level detection part 6p invalid during the invalid time, and performing transmission control to detect a liquid level based on a liquid level detection signal received after elapse of the invalid time. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a dispensing device that dispenses a liquid after detecting the liquid level of the liquid to be dispensed by a liquid level sensing means, an automatic analyzer including the dispensing device, and a liquid level sensing method.

  Conventionally, in order to prevent carryover or contamination during sample or reagent dispensing, dispensing is performed by inserting a predetermined amount of probe after detecting the sample or reagent liquid level. Various methods have been proposed for detecting the liquid level, such as an electrostatic capacitance method, a pressure detection method in a pipe connected to a probe, and an optical method. In the liquid level detection method based on the capacity, liquid level error is detected in the liquid level detection by the electrostatic capacity method due to sudden noise from peripheral devices or discharge between the container and the probe due to charging of the container containing the specimen or reagent. Detection sometimes occurred.

  In order to prevent this misdetection of the liquid level, by switching the speed of descent of the probe into the container from high speed to low speed, the allowable value of the noise generation time is lengthened and liquid level misdetection due to noise is prevented. An automatic analyzer is disclosed (for example, see Patent Document 1).

  Also, after detecting the liquid level based on the capacitance value and stopping the descent of the probe, it is re-determined whether the capacitance value detected after the lapse of a predetermined period is due to the liquid level detection or due to discharge. When it is determined, a dispensing device that lowers the probe again to detect the liquid level is disclosed (for example, see Patent Document 2).

JP 2000-171470 A JP 2008-70264 A

  However, in the thing of patent document 1, in the case of a liquid level detection, since the descent | fall speed of a dispensing probe is reduced, the time required for a liquid level detection becomes long, and there exists a possibility of causing the fall of analytical processing capability.

  In addition, since the probe described in Patent Document 2 temporarily stops the probe after detecting the liquid level and then determines again whether the liquid level is detected or erroneously detected after a predetermined time has elapsed, the time required for detecting the liquid level becomes longer. , There is a risk of reducing the analytical processing capacity.

  The present invention has been made in view of the above, and can prevent erroneous detection of the liquid level in the capacitive liquid level detection to obtain highly reliable analysis data, and can perform rapid liquid level detection. An object of the present invention is to provide a dispensing device, an automatic analyzer, and a liquid level detection method that can be performed.

  In order to solve the above-described problems and achieve the object, the dispensing device of the present invention detects a change in capacitance between a probe for dispensing a liquid contained in a container and the container, and detects the change. And a liquid level detecting means for determining whether or not the lower end of the probe is in contact with the liquid level of the liquid based on the received signal, wherein the liquid level height of the liquid stored in the plurality of containers is determined. The liquid level information storing means for storing the liquid level information included for each container, and the signal transmitted from the liquid level detecting means is invalidated based on the liquid level information stored for each container by the liquid level information storing means. The calculation means for calculating the invalid time, and the liquid level detection signal from the liquid level detection means is invalidated within the invalid time calculated by the calculation means, and the liquid level is detected based on the liquid level detection signal received after the invalid time has elapsed. Liquid level detection signal for transmission control to detect the surface Characterized in that it comprises a control means.

  In the dispensing device of the present invention, in the above invention, the liquid level information storage unit stores the descent time of the probe by the probe driving unit at the previous dispensing as liquid level information of the liquid stored in the container. The calculating means calculates the invalid time based on the probe lowering time at the previous dispensing.

  Further, in the dispensing device of the present invention, in the above invention, the liquid level information storage unit stores an invalid time at the time of previous dispensing as liquid level information of the liquid stored in the container, and the calculation unit includes: The invalid time is calculated by adding the time required for the probe to descend due to the liquid level drop caused by the previous dispensing to the invalid time at the previous dispensing.

  In the dispensing device of the present invention, in the above invention, the liquid level information storage means uses the liquid level detected by the liquid level detecting means at the time of previous dispensing as the liquid level information of the liquid stored in the container. The calculation means stores the invalid time based on the liquid level detected at the time of the previous dispensing.

  In the dispensing device of the present invention, in the above invention, the liquid level information storage means includes the liquid level information of the liquid stored in the container, the initial liquid level height and the number of times of dispensing stored in the container. And the calculation means calculates an invalid time based on the liquid level height calculated from the initial liquid level height and the number of dispensings of the container.

  In the dispensing device of the present invention, in the above invention, the calculating unit calculates the invalid time using a correction amount that takes into account the stopping accuracy of the probe driving unit and the liquid shaking accompanying the conveyance of the container. It is characterized by.

  The dispensing device of the present invention is a reagent dispensing device for dispensing a reagent in the above invention.

  An automatic analyzer according to the present invention is an automatic analyzer that optically analyzes a reaction product between a specimen and a reagent, and includes the dispensing device according to any one of the above.

  Further, the liquid level detection method of the present invention detects a change in capacitance between a probe for dispensing a liquid contained in a container and the container, and controls the liquid level of the liquid based on the detected signal. A liquid level detection method for determining whether or not the lower end of the probe has come into contact with the liquid level information including the liquid level height of the liquid stored in the container stored in the liquid level information storage means. And a calculation step for calculating an invalid time for invalidating the liquid level detection signal based on the liquid level information extracted by the extraction step, and invalidating the liquid level detection signal within the invalid time calculated by the calculation step, And a liquid level detection signal control step for performing transmission control so as to detect the liquid level based on the liquid level detection signal received after the invalid time has elapsed.

  In the liquid level detection method of the present invention, in the above invention, the extracting step extracts the descending time of the probe by the probe driving means at the time of the previous dispensing stored in the liquid level information storage means, and the calculating step Is characterized in that the invalid time is calculated based on the probe descending time at the previous dispensing time extracted in the extraction step.

  Further, in the liquid level detection method of the present invention, in the above invention, the extraction step extracts an invalid time at the time of the previous dispensing stored in the liquid level information storage means, and the calculation step is the extraction step. The invalid time is calculated by adding the time required for the probe to descend due to the liquid level drop caused by the previous dispensing to the invalid time at the previous dispensing.

  In the liquid level detection method of the present invention, in the above invention, the extraction step extracts the liquid level detected at the previous dispensing stored in the liquid level information storage means, and the calculation step includes the extraction The invalid time is calculated based on the liquid level detected at the time of the previous dispensing extracted in the step.

  Further, in the liquid level detection method of the present invention, in the above invention, the extraction step extracts an initial liquid level height and the number of times of dispensing of the liquid stored in the container stored in the liquid level information storage unit, In the calculating step, the invalid time is calculated based on the initial liquid level height of the container extracted in the extracting step and the liquid level height calculated from the number of dispensing.

  In the liquid level detection method of the present invention, in the above invention, the calculation step calculates the invalid time using a correction amount that takes into account the stopping accuracy of the probe driving means and the liquid shaking accompanying the conveyance of the container. It is characterized by that.

  Moreover, the liquid level detection method of the present invention is characterized in that, in the above-mentioned invention, it is used when a reagent is dispensed.

  The present invention is based on the approximate time required for detecting the liquid level from the start of the descent of the probe to the detection of the liquid level for each container. By calculating the liquid level detection invalid time taking into account and limiting the transmission of the liquid level detection signal by invalidating the liquid level detection signal within the invalid time, the frequency of false detection of liquid level due to noise is greatly reduced. As a result, highly reliable analysis data can be obtained, and the liquid level can be detected quickly.

FIG. 1 is a schematic configuration diagram of an automatic analyzer including a first reagent dispensing device according to an embodiment of the present invention. FIG. 2 is a block diagram showing a schematic configuration of the first reagent dispensing apparatus shown in FIG. FIG. 3 is a block diagram illustrating a schematic configuration of the capacitance type liquid level detection unit illustrated in FIG. 2. FIG. 4 is a diagram showing the relationship between the liquid level of the reagent stored in the reagent container and the number of aspirations. FIG. 5 is a diagram illustrating the relationship between the probe descent time into the reagent container and the number of times the reagent is aspirated. FIG. 6 is a diagram for explaining an invalid time at the time of liquid level detection in the reagent dispensing device. FIG. 7 is a diagram illustrating the relationship between the driving signal of the probe driving unit and time (nth dispensing). FIG. 8 is a diagram showing the relationship between the driving signal of the probe driving unit and time (n + 1 first dispensing). FIG. 9 is a flowchart of the reagent dispensing operation according to the embodiment. FIG. 10 is a flowchart for explaining the liquid level detection process.

  Exemplary embodiments of a dispensing device, an automatic analyzer, and a liquid level detection method according to the present invention will be explained below in detail with reference to the accompanying drawings. In addition, this invention is not limited to these embodiment, A various change is possible in the range which does not deviate from the summary of this invention.

  FIG. 1 is a schematic configuration diagram of an automatic analyzer including a dispensing device according to an embodiment of the present invention.

  The automatic analyzer 1 is an apparatus that automatically analyzes a sample such as blood or urine containing blood cell components. As shown in FIG. 1, the first and second reagent tables 2 and 3, the reaction table 4, the first and first 2 reagent dispensing devices 6 and 7, sample container transfer mechanism 8, rack 9, analysis optical system 11, cleaning mechanism 12, first and second stirring devices 13 and 14, control unit 15, input unit 16, display unit 17, An analysis unit 18, a storage unit 19, and a sample dispensing device 20 are provided.

  As shown in FIG. 1, the first reagent table 2 includes a plurality of reagent containers 2a for the first reagent arranged in the circumferential direction, and is rotated by a driving unit to convey the reagent containers 2a in the circumferential direction. Each of the plurality of reagent containers 2a is filled with a reagent corresponding to the inspection item, and an information recording medium (not shown) on which information such as the type, lot, and expiration date of the stored reagent is recorded is added to the outer surface. . Here, on the outer periphery of the first reagent table 2, a reading device 10a that reads the reagent information recorded on the information recording medium added to the reagent container 2a and outputs it to the control unit 15 is installed.

  The first reagent dispensing device 6 includes an arm 6a that freely moves up and down in the vertical direction and rotates around a vertical line passing through its base end as a central axis. A probe 6b for aspirating and discharging the specimen is attached to the tip of the arm 6a. The first reagent dispensing device 6 includes an intake / exhaust mechanism such as a syringe pump. The first reagent dispensing device 6 sucks the first reagent from the reagent container 2a transferred to the predetermined position on the first reagent table 2 by the probe 6b, and rotates the arm 6a clockwise in the drawing. Then, the first reagent is discharged into the reaction vessel 5 to perform dispensing.

  As shown in FIG. 1, the second reagent table 3 includes a plurality of second reagent reagent containers 3a arranged in the circumferential direction, and is rotated by a driving unit to convey the reagent containers 3a in the circumferential direction. Each of the plurality of reagent containers 3a is filled with a reagent corresponding to the inspection item, and an information recording medium (not shown) on which information such as the type, lot, and expiration date of the stored reagent is recorded is added to the outer surface. . Here, on the outer periphery of the second reagent table 3, a reading device 10 b that reads the reagent information recorded on the information recording medium added to the reagent container 3 a and outputs it to the control unit 15 is installed.

  The second reagent dispensing device 7 includes an arm 7a that freely moves up and down in the vertical direction and rotates around the vertical line passing through the base end of the second reagent as a central axis. A probe 7b for aspirating and discharging the sample is attached to the tip of the arm 7a. The second reagent dispensing device 7 includes an intake / exhaust mechanism such as a syringe pump. The second reagent dispensing device 7 sucks the second reagent from the reagent container 3a transferred to the predetermined position on the second reagent table 3 by the probe 7b, and turns the arm 7a counterclockwise in the figure. Then, the second reagent is discharged into the reaction vessel 5 to perform dispensing.

  As shown in FIG. 1, the reaction table 4 includes a plurality of reaction vessels 5 arranged in the circumferential direction. The reaction table 4 is arrowed by a driving means different from the driving means for driving the first and second reagent tables 2 and 3. To move the reaction vessel 5 in the circumferential direction. The reaction table 4 is disposed between the light source 11a and the spectroscopic unit 11b, and has a holding unit 4a that holds the reaction vessel 5 and an optical path 4b that includes a circular opening that guides the light beam emitted from the light source 11a to the spectroscopic unit 11b. is doing. The holding part 4a is arranged on the outer periphery of the reaction table 4 at a predetermined interval along the circumferential direction, and an optical path 4b extending in the radial direction is formed on the inner peripheral side of the holding part 4a.

  The reaction vessel 5 is an optically transparent material that transmits 80% or more of the light contained in the analysis light (340 to 800 nm) emitted from the analysis optical system 11, such as glass containing heat-resistant glass, cyclic olefin, or polystyrene. It is a container called a cuvette formed into a square cylinder shape by the like. In the reaction container 5, reagents are dispensed from the reagent containers 2 a and 3 a of the first and second reagent tables 2 and 3 by first and second reagent dispensing devices 6 and 7 provided in the vicinity. Here, the first and second reagent dispensing devices 6 and 7 are respectively provided with probes 6b and 7b that rotate in a horizontal plane and dispense reagents to arms 6a and 7a that are moved up and down in the vertical direction. A cleaning tank (not shown) for cleaning the probes 6b and 7b with cleaning water is provided.

  As shown in FIG. 1, the specimen container transfer mechanism 8 transfers the plurality of arranged racks 9 while stepping one by one along the arrow direction. The rack 9 holds a plurality of sample containers 9a that store samples. Here, the sample container 9a is affixed with a bar code or the like on which information on the stored sample is affixed, and every time the advance of the rack 9 transported by the sample container transport mechanism 8 stops, Is dispensed into each reaction vessel 5. A blood sample whose analysis item is blood glucose or hemoglobin A1c is centrifuged in a state where it is previously stored in the sample container 9a, and the plasma sample and the blood cell sample are analyzed items from the blood sample separated into the plasma layer and the blood cell layer. It will be dispensed individually. Here, on the outer periphery of the rack, a reading device 10c that reads the sample information and the container information of the sample container 9a recorded on an information recording medium (not shown) attached to the sample container 9a and outputs it to the control unit 15. Is installed.

  The sample dispensing device 20 includes an arm 20a that freely moves up and down in the vertical direction and rotates around a vertical line passing through the base end of the sample dispensing apparatus 20 as a central axis. A probe 20b for aspirating and discharging the specimen is attached to the tip of the arm 20a. The sample dispensing device 20 includes an intake / exhaust mechanism such as a syringe pump. The sample dispensing device 20 sucks the sample by the probe 20b from the sample container 9a transferred to the dispensing position by the sample container transfer mechanism 8, and rotates the arm 20a clockwise in the drawing to place the sample in the reaction container 5. To dispense.

  The analysis optical system 11 is an optical system for analyzing by transmitting the analysis light (340 to 800 nm) through the liquid sample in the reaction container 5 in which the reagent and the sample have reacted, and includes a light source 11a, a spectroscopic unit 11b, and a light receiving unit. 11c. The analysis light emitted from the light source 11a passes through the liquid sample in the reaction vessel 5 and is received by the light receiving unit 11c provided at a position facing the spectroscopic unit 11b. The light receiving unit 11 c is connected to the control unit 15.

  The cleaning mechanism 12 sucks and discharges the liquid sample in the reaction vessel 5 by the nozzle 12a, and then repeatedly injects and sucks a cleaning liquid such as detergent and cleaning water by the nozzle 12a, thereby performing analysis by the analysis optical system 11. The reaction vessel 5 that has been completed is washed.

  The first and second stirring devices 13 and 14 stir the dispensed specimen and reagent with the stirring rods 13a and 14a to promote the reaction.

  The control unit 15 includes the first and second reagent tables 2 and 3, the first and second reagent dispensing devices 6 and 7, the sample container transfer mechanism 8, the analysis optical system 11, the cleaning mechanism 12, and the first and second stirring. The devices 13 and 14, the input unit 16, the display unit 17, the analysis unit 18, the storage unit 19, and the sample dispensing device 20 are connected. In order to control the operation of these units, a microcomputer or the like is used as the control unit 15. The control unit 15 obtains the absorbance for each wavelength of the liquid sample in each reaction vessel 5 based on the light amount signal for each wavelength input from the light receiving unit 11c, and analyzes the component concentration and the like of the specimen. In addition, the control unit 15, based on the information read from the information recording medium added to the reagent containers 2 a, 3 a, the automatic analyzer 1 so as to stop the analysis work when the reagent lot is different or when the expiration date is out of date. Or alert the operator.

  The input unit 16 is configured by using a keyboard, a mouse, and the like, and acquires various information necessary for analyzing a sample, instruction information for analysis operation, and the like from the outside. The display unit 17 is configured using a printer, a communication mechanism, and the like, and outputs various information including the analysis result of the sample to notify the user. The analysis unit 18 calculates absorbance and the like based on the measurement result acquired from the analysis optical system 11, and performs component analysis of the specimen. The storage unit 19 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 automatic analyzer 1 executes the process. Various information including the analysis result of the specimen is stored. The storage unit 19 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.

  In the automatic analyzer 1 configured as described above, the first reagent dispensing device 6 dispenses the first reagent in the reagent container 2a to the plurality of reaction containers 5 that are sequentially conveyed in a row. Thereafter, the sample dispensing device 20 dispenses the sample in the sample container 9a, the second reagent dispensing device 7 dispenses the second reagent in the reagent container 3a, and the analysis optical system 11 causes the sample and the reagent to be dispensed. The sample is in a state of being reacted with each other, and the analysis unit 18 analyzes the measurement result, so that the component analysis of the specimen is automatically performed. In addition, the cleaning mechanism 12 is cleaned while transporting the reaction vessel 5 after the measurement by the analysis optical system 11 is completed, so that a series of analysis operations are continuously repeated.

  Next, the embodiment of the present invention will be described in detail with reference to FIG. 2 and FIG. 3 by taking the liquid level detection in the first reagent dispensing device 6 as an example. FIG. 2 is a block diagram showing a schematic configuration of the first reagent dispensing device 6. FIG. 3 is a block diagram showing a schematic configuration of the capacitance type liquid level detection unit 6p.

  As shown in FIG. 2, the first reagent dispensing device 6 includes a probe 6b, a probe driving unit 6d, a dispensing pump 6e, a pump driving unit 6g, a washing water pump 6l, a washing water tank 6n, a liquid level detection unit 6p, A liquid level detection determination unit 6q is provided.

  As shown in FIG. 1, the first reagent dispensing device 6 rotates in a horizontal plane and is provided with a probe 6 b for dispensing the first reagent on an arm 6 a that is lifted up and down. It has a cleaning tank (not shown) for cleaning 6b. As shown in FIG. 2, the probe 6b is connected to the dispensing pump 6e by a pipe 6c, and the dispensing pump 6e and the washing water pump 61 are connected via a pipe 6h. The probe 6b is moved in the horizontal direction indicated by the arrow X and the vertical direction indicated by Z in the drawing by the probe driving unit 6d, and the first reagent is aspirated from the reagent container 2a conveyed to the lower part of the probe 6b. The first reagent is dispensed by discharging the reagent into the reaction vessel 5 on the reaction table 4.

  The dispensing pump 6e is a syringe pump that discharges the first reagent sucked into the reaction container 5 conveyed by the reaction table 4 after the probe 6b sucks the first reagent in the reagent container 2a. The piston 6f is reciprocated by 6g.

  The cleaning water pump 6l sucks up the degassed cleaning water L1 stored in the cleaning water tank 6n and pumps it into the pipe 6h through the electromagnetic valve 6k. At this time, the electromagnetic valve 6k is switched to “open” when the sucked wash water L1 is pumped into the pipe 6h by the control signal from the control unit 15, and the probe 6b is switched to the first reagent by the dispensing pump 6e. Is sucked and discharged, it is switched to “closed”.

  The liquid level detector 6p detects the liquid level of the first reagent accommodated in the reagent container 2a. As shown in FIG. 3, the liquid level detection unit 6p includes an oscillation circuit 101 and a liquid level detection circuit 102, and a metal plate 2c is disposed near the bottom of the reagent container 2a.

  As shown in FIG. 3, the liquid level detection circuit 102 includes an amplifier 102a, a diode 102b, a capacitor 102c, and a comparator 102d.

  The liquid level detector 6p detects the liquid level based on a change in capacitance between the probe 6b and the first reagent in the reagent container 2a based on the oscillation signal transmitted from the oscillation circuit 101. The amplifier 102a The diode 102b amplifies the oscillation signal introduced into the amplifier 102a, rectifies and smoothes the oscillation signal amplified by the amplifier 102a in cooperation with the capacitor 102c, and outputs the smoothed signal to the comparator 102d.

  The comparator 102d compares the input smoothed signal (voltage) with a separately input reference value signal (voltage). The comparator 102d outputs a liquid level detection signal to the liquid level detection determination unit 6q when the input smoothing signal (voltage) is larger than the reference value signal (voltage), but a liquid level detection signal control unit 6t described later. Determines that the liquid level detection signal transmitted from the comparator 102d is invalid within the invalid time calculated by the calculation unit 6s, restricts transmission of the liquid level detection signal to the control unit 15, and the invalid time has elapsed. After the determination, the liquid level detection signal transmitted from the comparator 102d is transmitted to the control unit 15.

  As shown in FIG. 2, the liquid level detection determination unit 6q includes a liquid level information storage unit 6r, a calculation unit 6s, and a liquid level detection signal control unit 6t. The liquid level information storage unit 6r is a probe driving unit at the time of previous dispensing as liquid level information including the liquid level height of the first reagent stored in all the reagent containers 2a placed on the first reagent table 2. The descending time of the probe 6b by 6d is stored for each reagent container 2a. The descending time of the probe 6b is the first descending time until the liquid level is detected from the top dead center where the probe 6b is transported onto the reagent container 2a containing the first reagent to be dispensed and starts descending. This is the time obtained by adding the dive time into the liquid for reagent aspiration. In the case of a new reagent container 2a that has not yet been dispensed, a time obtained by adding the dive time to the descent time predicted from the initial liquid level height determined for each type of reagent container 2a is used. The type and discrimination of the reagent container 2a are performed by reading the reagent information recorded on the information recording medium added to the reagent container 2a by the reading device 10a shown in FIG.

  The calculation unit 6s calculates an invalid time for invalidating the signal transmitted from the liquid level detection unit 6p based on the descending time of the probe 6b at the previous dispensing time stored in the liquid level information storage unit 6r for each reagent container 2a. . The liquid level detection signal control unit 6t determines whether or not the invalid time calculated by the calculation unit 6s has elapsed from the descent start time of the probe 6b to the reagent container 2a. If the invalid time has not elapsed, the control unit 15 The liquid level detection signal transmitted from the liquid level detection unit 6p is transmitted to the control unit 15 after the invalid time has elapsed after the transmission of the liquid level detection signal to is limited.

  When the liquid level is detected by the liquid level detection signal transmitted from the liquid level detection determination unit 6q, the control unit 15 further drives the probe 6b by driving the probe driving unit 6d in order to suck a predetermined amount of the first reagent. Control is performed to stop the probe 6b after being lowered so as to be immersed in one reagent. Thereafter, the control unit 15 controls the probe 6b to suck a predetermined amount of the first reagent by retreating the piston 6f of the dispensing pump 6e by driving the pump driving unit 6g.

  Next, a method for calculating the invalid time by the calculation unit 6s of the liquid level detection determination unit 6q will be described. FIG. 4 is a diagram showing the relationship between the liquid level height of the reagent stored in the reagent container 2a and the number of aspirations. FIG. 5 is a diagram illustrating the relationship between the descending time of the probe 6b into the reagent container 2a and the number of times the reagent is aspirated. FIG. 6 is a diagram for explaining the invalid time when the liquid level is detected by the first reagent dispensing device 6.

As shown in FIG. 4, when the first reagent is dispensed from the reagent container 2a, the liquid level of the first reagent to be accommodated decreases according to the number of times of suction, and correspondingly, as shown in FIG. As described above, the descending time of the probe 6b into the reagent container 2a by the probe driving unit 6d increases. In the embodiment of the present invention, a correction amount Δh is introduced that takes into account the stopping accuracy of the probe driving unit 6d and the liquid shaking of the first reagent accommodated in the reagent container 2a accompanying the transport of the reagent container 2a. invalid time period for lowering the amount of correction of △ h min higher by up to h _b1 probe 6b from the surface h1, within the dead time can be liquid level detection signal from the liquid level detection unit 6p is transmitted to the control unit 15 Control is performed so as not to transmit the liquid level detection signal. Δh is a fixed value as shown in FIG. 4, is determined for each reagent container 2a, and stored together with the liquid level information of each reagent container 2a in the liquid level information storage unit 6r. Correction amount △ h, as shown in FIG. 5, may be stored as a time T _b required to drop △ h. Figure 6 shows the state of the liquid level detection of the first time dispensing from the reagent container 2a, probes 6b, even if the liquid level detection unit 6p has originated the liquid level detection signal by the noise detection, the top dead center h _a from up from the initial liquid level height h ₁ △ h high h _b1 is △ H ₁ minute drop without being stopped. As a result, it is possible to prevent erroneous detection of the liquid level due to noise from peripheral devices and electrostatic discharge charged in the reagent container 2a. In particular, since electrostatic discharge is likely to occur near the dispensing port of the reagent container 2a, by providing an invalid time for the liquid level detection signal, it is possible to effectively block erroneous liquid level detection occurring near the dispensing port. Can do.

  The liquid level information of the reagent stored in the reagent container 2a is calculated from the probe lowering time by the probe driving means at the time of the previous dispensing, and the probe lowering time at the previous dispensing for each reagent container 2a is the liquid level information. The data is stored in the storage unit 6r. For example, when n times of dispensing has already been performed from the reagent container 2a and n + 1 time is dispensed, the descending time of the probe at the time of the nth dispensing of the reagent container 2a is extracted from the liquid level information storage unit 6r.

FIG. 7 is a diagram showing the relationship between the drive signal of the probe drive unit 6d and time (nth dispensing), and FIG. 8 is a diagram showing the relationship between the drive signal of the probe drive unit 6d and time (n +). First dispensing). As shown in FIG. 7, the probe driving unit 6d begins descending from the top dead center h _a at time t _{0 (n),} to the time the invalid time ends t _{1 (n)} is the liquid from the liquid level detection unit 6p Even when the surface detection signal is transmitted, the liquid level detection determination unit 6q does not transmit the signal to the control unit 15, and the probe 6b is lowered without stopping. After time t _{1 (n) has} elapsed, the liquid level detection determination unit 6q releases the restriction on the transmission of the liquid level detection signal to the control unit 15, and when the liquid level detection unit 6p detects a change in capacitance, the control unit 15 A liquid level detection signal is transmitted to the liquid and the liquid level is detected by receiving the signal. The liquid level in the stopping accuracy and the reagent containers 2a correction amount T _b obtained by adding the time t _{2 (n)} near Considering liquid sway associated with the transport of the probe drive unit 6d disable time T _{a (n)} is detected, further After the time t _{3 (n) when} the dive time T _c into the first reagent is added, the descent of the probe 6b is stopped and the first reagent is aspirated.

Accordingly, the invalid time T _{a (n)} is obtained by subtracting the correction amount T _b and the dive time T _c from the probe lowering time T _{c (n)} . As shown in FIGS. 4, 5 and 8, since the reagent liquid surface by the n-th dispensing is reduced by △ h _d, dead time T _{a (n + 1)} is a probe 6b △ h _d only time _{T d} required to minute drops longer than invalid time _{T a (n),} calculates a dead time _{T a (n + 1)} by adding the _{T d} disable time _{T a (n).}

  Next, the reagent dispensing operation in the embodiment of the present invention will be described. FIG. 9 is a flowchart of the reagent dispensing operation according to the embodiment of the present invention. FIG. 10 is a flowchart for explaining the liquid level detection process shown in FIG.

First, the control unit 15 acquires the dispensing information such as the type of the first reagent to be dispensed and the amount to be dispensed from the storage unit 19 (step S101), and the driving unit (not shown) of the first reagent table 2 Control is performed to transport the reagent container 2a containing the first reagent to be dispensed to the dispensing position (step S102). After the conveyance, the liquid level detection determination unit 6q extracts, from the liquid level information storage unit 6r, the descending time _{Tc (n)} of the probe 6b by the probe driving unit 6d at the previous dispensing time in the reagent container 2a to be dispensed. (Step S103). When dispensing from the reagent container 2a for the first time, _{Tc (1)} is calculated based on the initial liquid level height and the penetration depth stored in the liquid level information storage unit 6r.

Based on the extracted falling time _{Tc (n)} , the calculation unit 6s calculates the invalid time T _{a (n + 1)} (step S104). Invalid time T _{a (n + 1)} is subtracted correction amount _{T b} and slip time _{T c} from the fall time _{T c (n),} the time obtained by adding the _{T d.} Next, a liquid level detection process is performed (step S105), and the first reagent is aspirated (step S106). The probe 6b is transported to the discharge position by driving the probe drive unit 6d, and the aspirated first reagent is discharged to the predetermined reaction container 5 transported to the discharge position by the drive means of the reaction table 4 (not shown) (step S107). . Thereafter, the probe 6b is cleaned in a cleaning tank (not shown) (step S108). The control unit 15 confirms whether or not all the dispensing of the first reagent has been completed (step S109). If the dispensing has not been completed (step S109, No), the dispensing of the first reagent is started from step S101. Repeated. If all dispensing has been completed (step S109, Yes), the dispensing operation of the first reagent is terminated.

  Next, the liquid level detection process in the reagent dispensing operation will be described with reference to FIG. In the liquid level detection process of step S105 shown in FIG. 9, first, the probe 6b is lowered into the reagent container 2a by driving the probe drive unit 6d (step S201), and the liquid level detection by the liquid level detection unit 6p is performed with the lowering. Start (step S202). Until the liquid level detection unit 6p detects the liquid level due to the change in capacitance (No in step S203), the probe 6b is lowered and when the liquid level is detected (step S203, Yes), the liquid level detection signal control unit 6t. Determines whether the invalid time calculated by the calculating means 6s has elapsed since the start of the descent of the probe 6b (step S204). If it is determined that the invalid time has not elapsed (step S204, No), the liquid level detection signal control unit 6t does not transmit the liquid level detection signal to the control unit 15, and the descent of the probe 6b is continued. If the liquid level detection signal control unit 6t determines that the invalid time has elapsed (step S204, Yes), the liquid level detection signal is transmitted to the control unit 15 (step S205). After the liquid level of one reagent is recognized and the probe driving unit 6d is driven to cause the probe 6b to enter the first reagent by a predetermined amount, control is performed to stop the descent of the probe 6b (step S206). Thereafter, the probe descent time measured during dispensing is stored in the liquid level information storage unit 6r (step S207), and the process of step S106 shown in FIG. 9 is performed.

  According to the embodiment of the present invention, it is possible to prevent erroneous detection of the liquid level due to static electricity or external noise, and thus it is possible to prevent the probe 6b from stopping in the air. Moreover, since this can prevent empty suction, the analysis result can be stabilized. Furthermore, since the dispensing operation time can be made constant, the effect of preventing a reduction in throughput is also achieved.

  The embodiment of the present invention has been described by taking the first reagent dispensing device 6 as an example, but the second reagent dispensing device 7 can also achieve the object of the present invention by adopting the same configuration. In the sample dispensing apparatus 20 as well, the maximum capacity that can be accommodated for each type of sample container 9a is stored as the initial liquid volume, and then the above-described implementation is performed when the sample is dispensed from the same sample container 9a. Similarly to the above-described embodiment, the ineffective time is calculated based on the descending time of the probe to determine whether or not the liquid level detection signal can be transmitted, thereby reducing the occurrence of liquid level erroneous detection due to noise.

Further, as a first modification of the above-described embodiment, the calculation unit 6s calculates the invalid time based on the invalid time at the previous dispensing, and the liquid level detection signal control unit 6t determines that the liquid level is within the invalid time. The 1st reagent dispensing apparatus 6 which controls not to transmit the liquid level detection signal from the detection part 6p to the control part 15 is illustrated. In the first modification, the liquid level information storage unit 6r stores the invalid time (T _{a (n)} , see FIGS. 5 and 7) at the previous dispensing time, instead of the probe lowering time. The calculating unit 6s adds the time T _d (see FIG. 8) required for the probe descent according to the liquid level drop by the previous dispensing to the invalid time _{Ta (n)} at the time of the previous dispensing to add the invalid time T _{a ( n + 1)} is calculated. Transmission control of the liquid level detection signal by the liquid level detection signal control unit 6t is the same as in the above-described embodiment.

Further, as a second modification of the above-described embodiment, the calculation unit 6s calculates the invalid time based on the liquid level detected at the time of the previous dispensing, and the liquid level detection signal control unit 6t is within the invalid time. The 1st reagent dispensing apparatus 6 which controls not to transmit the liquid level detection signal from the liquid level detection part 6p to the control part 15 is illustrated. In the second modification, the liquid level information storage unit 6r is required for lowering the liquid level height (h _n , see FIG. 4) or the liquid level height h _n of the first reagent detected at the time of the previous dispensing instead of the probe lowering time. The time (T _{b (n)} , see FIGS. 5 and 7) is stored. Calculator 6s from time _{T b} required for lowering the liquid level _{h n} or liquid level _{h n} of the previous dispensing _(n), dead time by subtracting the correction amount △ h or _{T b T a (n + 1)} is calculated. Transmission control of the liquid level detection signal by the liquid level detection signal control unit 6t is the same as in the above-described embodiment.

Furthermore, as a third modification of the above-described embodiment, the calculation unit 6s calculates the invalid time based on the initial liquid level height and the number of dispensings of the first reagent stored in the reagent container 2a, and detects the liquid level. The signal control unit 6t is exemplified by the first reagent dispensing device 6 that performs control so that the liquid level detection signal from the liquid level detection unit 6p is not transmitted to the control unit 15 during the invalid time. In variation 3, the liquid level information storage section 6r includes, instead of the probe falling time storing an initial liquid surface height and dispensing times (h ₁ and n, see FIGS. 4 and 6). Calculator 6s is calculated based on the initial liquid level height h ₁ and the dispensing number n, the time T _b required for lowering the liquid level h _n or liquid level h _n of the previous dispensing a _(n), The invalid time T _{a (n + 1)} is calculated by subtracting the correction amount Δh or T _b . Transmission control of the liquid level detection signal by the liquid level detection signal control unit 6t is the same as in the above-described embodiment.

Incidentally, in the above embodiment, the correction amount △ h or T _b of the liquid sway due to transport of the stopping accuracy and reagent vessels 2a considering the probe driving unit 6d is that a fixed value, is accommodated in the reagent container 2a In consideration of the liquid amount of the first reagent, it may be stored in the liquid surface information storage unit 6r as a function of the liquid amount.

  As described above, the dispensing device, the automatic analyzer, and the liquid level detection method of the present invention are useful for an analyzer that analyzes a reaction product between a specimen and a reagent, and particularly in fields where analysis accuracy is required. Is suitable.

DESCRIPTION OF SYMBOLS 1 Automatic analyzer 2, 3 1st and 2nd reagent table 2a, 3a Reagent container 2c Metal plate 4 Reaction table 4a Holding part 4b Optical path 5 Reaction container 6, 7 1st and 2nd reagent dispensing apparatus 6a, 7a, 20a Arm 6b, 7b, 20b Probe 6c, 6h Piping 6d Probe drive 6e Dispensing pump 6f Piston 6g Pump drive 6k Solenoid valve 6l Washing water pump 6n Washing water tank 6p Liquid level detection unit 6q Liquid level detection determination unit 6r Liquid level Information storage unit 6s Calculation unit 6t Liquid level detection signal control unit 8 Sample container transfer mechanism 9 Rack 9a Sample container 10a, 10b, 10c Reader 11 Analytical optical system 12 Cleaning mechanism 13, 14 First and second agitator 15 Control unit 16 Input unit 17 Display unit 18 Analysis unit 19 Storage unit 20 Sample dispensing apparatus 101 Oscillation circuit 102 Liquid level inspection Circuit L1 wash water

Claims (15)

Detecting a change in capacitance between the probe that dispenses the liquid contained in the container and the container, and determining whether the lower end of the probe is in contact with the liquid level of the liquid based on the detected signal A dispensing device comprising a liquid level detecting means for performing
Liquid level information storage means for storing the liquid level information including the liquid level height of the liquid contained in the plurality of containers for each container,
Based on the liquid level information stored for each container by the liquid level information storage unit, a calculation unit that calculates an invalid time for invalidating a signal transmitted from the liquid level detection unit;
Liquid for which transmission control is performed so that the liquid level detection signal from the liquid level detection means is invalidated during the invalid time calculated by the calculation means and the liquid level is detected based on the liquid level detection signal received after the invalid time has elapsed. Surface detection signal control means;
A dispensing device comprising: The liquid level information storage means stores the descent time of the probe by the probe driving means at the time of the previous dispensing as the liquid level information of the liquid stored in the container,
The dispensing device according to claim 1, wherein the calculating unit calculates an invalid time based on a probe descending time at the previous dispensing. The liquid level information storage means stores the invalid time at the time of the previous dispensing as the liquid level information of the liquid stored in the container,
2. The dispensing device according to claim 1, wherein the calculating unit calculates an invalid time by adding a time required for the probe to descend due to a liquid level drop caused by the previous dispensing to an invalid time at the previous dispensing. . The liquid level information storage means stores the liquid level detected by the liquid level detection means at the time of previous dispensing as liquid level information of the liquid stored in the container,
The dispensing device according to claim 1, wherein the calculating unit calculates an invalid time based on a liquid level detected at the time of previous dispensing. The liquid level information storage means stores the initial liquid level height and the number of dispensing of the liquid stored in the container as the liquid level information of the liquid stored in the container,
The dispensing device according to claim 1, wherein the calculating means calculates an invalid time based on a liquid level height calculated from an initial liquid level height and the number of times of dispensing of the container.   The said calculating means calculates the said invalid time using the correction amount which considered the stop precision of the probe drive means, and the liquid shaking accompanying conveyance of the said container, The one of Claims 1-5 characterized by the above-mentioned. The dispensing device described in 1.   The dispensing apparatus according to any one of claims 1 to 6, wherein the dispensing apparatus is a reagent dispensing apparatus that dispenses a reagent. An automatic analyzer for optically analyzing a reaction product between a sample and a reagent,
An automatic analyzer comprising the dispensing device according to any one of claims 1 to 7. Detecting a change in capacitance between the probe that dispenses the liquid contained in the container and the container, and determining whether the lower end of the probe is in contact with the liquid level of the liquid based on the detected signal A liquid level detection method for
An extraction step for extracting liquid surface information including the liquid surface height of the liquid stored in the container stored in the liquid surface information storage means;
Based on the liquid level information extracted by the extraction step, a calculation step for calculating an invalid time for invalidating the liquid level detection signal;
A liquid level detection signal control step for performing transmission control so as to detect the liquid level based on the liquid level detection signal received after the invalid time has elapsed after invalidating the liquid level detection signal within the invalid time calculated by the calculation step; ,
The liquid level detection method characterized by including. The extraction step extracts the probe descent time by the probe driving means at the time of previous dispensing stored in the liquid level information storage means,
The liquid level detection method according to claim 9, wherein the calculating step calculates an invalid time based on a probe descending time at the previous dispensing time extracted in the extracting step. The extraction step extracts an invalid time at the time of the previous dispensing stored in the liquid level information storage means,
10. The calculation step of calculating the invalid time by adding the time required for the probe to descend due to the liquid level drop caused by the previous dispensing to the invalid time at the previous dispensing extracted in the extraction step. The liquid level detection method according to 1. The extraction step extracts the liquid level detected at the time of previous dispensing stored in the liquid level information storage means,
The liquid level detection method according to claim 9, wherein the calculation step calculates an invalid time based on the liquid level detected at the time of the previous dispensing extracted in the extraction step. The extraction step extracts the initial liquid level height and the number of dispensing times of the liquid stored in the container stored in the liquid level information storage means,
The liquid level detection according to claim 9, wherein the calculating step calculates an invalid time based on an initial liquid level height of the container extracted in the extraction step and a liquid level height calculated from the number of times of dispensing. Method.   14. The calculation step according to claim 9, wherein the invalidation time is calculated using a correction amount that takes into account the stopping accuracy of the probe driving means and the liquid shaking accompanying the conveyance of the container. The liquid level detection method according to 1.   The liquid level detection method according to any one of claims 9 to 14, wherein the liquid level detection method is used when a reagent is dispensed.

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