JP2000046624A - Analyser having liquid residual quantity detecting function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an analytical device capable of detecting a liquid residual- quantity of liquid in a vessel simply and accurately. SOLUTION: A nozzle 4 is supported downward on the head of an arm 5, and the back end of the arm 5 is fixed on the upper end of a shaft 6. The shaft 6 performs an upward and downward motion in the arrow A direction and a rotational motion in the arrow B direction by a drive unit 7 installed on a table 1. A reaction vessel 11 is loaded on a conveyor 12. A reagent vessel 3 is installed on the table 1 through an electrode 2. When the shaft 6 is moved downward and the head of the nozzle 4 is inserted into the reagent vessel 3, a liquid level sensor 15 detects the contact of the nozzle 4 to a reagent liquid level by the change of an electrostatic capacity between the nozzle 4 and the electrode 2. The nozzle 4 is moved downward as far as a prescribed quantity from the detected liquid level position and the reagent is sucked as much as a fixed quantity into a syringe 9 through the nozzle 4 and a tube 8. The shaft 6 is moved upward and rotated in the B direction, and the reagent is discharged into the reaction vessel 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an analyzer for repeatedly collecting a liquid contained in a container, and more particularly to an automatic analyzer using a large number of liquid reagents, such as a biochemical test or a blood coagulation test.

[0002]

2. Description of the Related Art In this type of analyzer, a required number and a necessary amount of reagents for measurement are prepared for measurement. If any of the reagents becomes insufficient during the measurement, the measurement must be performed again. Therefore, the remaining amount of each reagent must be confirmed. However, in many cases, a plurality of reagents are used in various numbers of times and once, and it is quite difficult to grasp the remaining amount of each reagent. It is troublesome to visually check the remaining amount of each reagent for each measurement, and when the amount of reagent used at one time is small, it is quite difficult to visually check the remaining amount.

Therefore, it is used to provide a function of inputting a usable amount at the start of use of the reagent and subtracting the used amount from the usable amount to the analyzer. However, the usable amount of the reagent must first be entered, and cannot be used for a reagent whose usable amount is unknown.

Therefore, in an analyzer provided with a liquid surface position detecting means, each time a reagent is collected from a reagent container, its liquid surface position is stored, and the amount of change in the liquid surface position, the amount of the collected reagent, and the amount of the collected reagent are determined. It is known that the remaining amount that can be collected is calculated from the relationship with the position of the lowest possible liquid level (for example, see Japanese Utility Model Publication No. 4-279). However, in such an apparatus, the change in the liquid level position per collection must be constant, that is, the cross-sectional area of the reagent container must be uniform. However, a reagent container having a non-uniform cross-sectional area, for example, a container having a narrow bottom as shown in FIG. 2 is often used as the reagent container.

Therefore, in a similar apparatus, the change in the liquid surface area is calculated from the amount of the sampled reagent and the change in the liquid surface position, so that the change in the cross-sectional area of the reagent container is made. There is known a method of recalculating the remaining amount that can be collected from the relationship between the change in the surface position, the amount of the collected reagent, and the position of the lowest liquid level that can be collected. (Japanese Patent Application Hei 8-27
9679). However, in this method, when the cross-sectional area of the liquid surface for aspirating the reagent changes, the change in the liquid surface cross-sectional area is detected and the calculation is performed again. Since the remaining amount of the reagent is calculated based on the cross-sectional area up to, the remaining amount of the reagent may vary considerably depending on the shape of the container.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and is not limited to the shape of a container containing a liquid, and accurately detects the remaining amount of the liquid when aspirating a reagent. It is intended to provide an analyzer capable of performing the analysis.

[0007]

SUMMARY OF THE INVENTION The present invention relates to a liquid collecting means for collecting a liquid contained in a container, a liquid surface position detecting means for detecting a liquid surface position in the container, and a container containing the liquid to be collected. Container type input means for inputting the type, comprising a relational expression storage means for storing in advance the relational expression between the liquid level and the remaining liquid amount in each container type, the liquid level position detected by the liquid level detection means, It is an object of the present invention to provide an analyzer wherein the residual liquid amount in the container is detected by the relational expression corresponding to the container type input by the container type input means.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An analyzer according to the present invention refers to an analyzer that repeatedly performs an operation of collecting a predetermined amount of liquid from a container by a liquid collecting means and supplying the collected liquid to a reaction container or the like. Examples of the analyzer include a biochemical analyzer and a blood coagulation analyzer.

As the liquid collecting means, a nozzle (dispensing pipette) for collecting a predetermined amount of liquid is preferably used. A nozzle (dispensing pipette) that collects a predetermined amount of liquid is preferably used for the liquid supply unit, and the same unit as the liquid collection unit can be used.

The liquid level detecting means includes an electric sensor for detecting that a nozzle as a liquid sampling means has contacted the liquid level by a change in capacitance or electric resistance, or optically monitors the liquid level. An optical sensor or the like can be applied.

As the container type input means, a reader for reading the size of the container itself or a barcode affixed to the container, a device simply inputting manually to the analyzer, or the like is used. The type of the container is not limited to the type of the container itself.
As described above, an adapter for tilting a container capable of sucking a reagent to the end is set as one type of container.

The amount of liquid remaining in the container may be all of the amount of liquid remaining in the container, but the amount excluding the amount that cannot be collected by the analyzer (dead volume), that is, the amount of liquid that can be sucked by the analyzer. It can be a liquid volume. The remaining liquid amount may be a liquid volume (ml or the like), but may be the remaining number of times that the liquid can be collected if the liquid collection amount is a fixed amount each time.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the embodiments shown in the drawings. This does not limit the present invention. FIG. 1 is a configuration explanatory view showing an embodiment of an analyzer according to the present invention. A nozzle 4 is supported downward at a tip of an arm 5, and a rear end of the arm 5 is fixed to an upper end of a shaft 6. The shaft 6 performs a vertical movement in the direction of arrow A and a rotational movement in the direction of arrow B by a driving device 7 provided on the table 1. In FIG. 1, a reaction vessel 11 is mounted on a conveyor 12 which moves in the horizontal direction on the paper. A reagent container 3 is set on a table 1 via an electrode 2.

When the tip of the nozzle 4 is inserted into the reagent container 3 by lowering the shaft 6, a change in the capacitance between the nozzle 4 and the electrode 2 causes the liquid level sensor 15 to move to the reagent liquid level of the nozzle 4. Detects contact. The nozzle 4 is lowered by a predetermined amount from the detected liquid level position, and the reagent is sucked into the syringe 9 by a certain amount via the nozzle 4 and the tube 8. When the shaft 6 rises and the nozzle tip is pulled out of the container 3, the shaft 6 rotates in the direction of arrow B. When the nozzle 4 reaches the upper part of the reaction vessel 11, the shaft 6 descends and the syringe 9
The reagent that has been sucked is discharged into the reaction container 11 by the above.

The control unit 13 processes output signals received from the input unit 14 and the liquid level sensor 15, and controls the stepping motor 10 for driving the syringe 9, the stepping motor 16 for moving the shaft 6 up and down in the direction of arrow A, and the shaft 6
Is controlled in the direction of arrow B to output to an output unit 18. Also,
The control unit 13 is configured by a microcomputer including a CPU, a ROM, and a RAM, and includes an input unit 14 and an output unit 18.
Are composed of a keyboard and a CRT, respectively. When the dispensing nozzle 4 is moved, the control unit 13 measures the amount of movement in the direction of arrow A by counting the number of drive pulses applied to the stepping motor 16 with the upper surface of the table 1 as a reference position. The rotation angle in the direction of arrow B is measured by counting the number of drive pulses applied to the stepping motor 17.

An operation of calculating the relational expression between the liquid level position in the container and the remaining liquid amount in the analyzer having such a configuration will be described. Note that this operation can be omitted for a container whose relational expression is known in advance. First, the type of the reagent container whose relational expression is to be obtained is input to the input unit 14 of the analyzer. The operation of calculating the relational expression by setting the container is started.

When the nozzle 4 descends into the container and comes into contact with the reagent liquid level, the reagent liquid level position H 0 is detected by the liquid level sensor 15. This reagent liquid surface position H0 is stored in the controller 13. Further, when the nozzle 4 descends by a predetermined distance,
The syringe 9 is operated by the stepping motor 10 to aspirate a predetermined amount V0 of the reagent. This reagent suction amount V0 is stored in the control unit 13. After aspirating the reagent, the dispensing nozzle 4
Rises, rotates in the direction of the arrow B, and the reagent sucked into the reaction chamber 11 is discharged.

The nozzle 4 from which the reagent has been discharged rises, rotates to the position of a washing section (not shown), and is washed by the washing section.
Then, when the liquid is rotated again to the position of the container, descends into the container, and comes into contact with the reagent liquid level, the reagent liquid level position H1 becomes the liquid level sensor 1
5 detected. The reagent liquid surface position H1 is stored in the control unit 13. When the nozzle 4 is further lowered by a predetermined distance, the syringe 9 is operated by the stepping motor 10 to suck a predetermined amount V1 of the reagent. The reagent suction amount V1 is stored in the control unit 13. After aspirating the reagent, the dispensing nozzle 4 rises, rotates in the direction of arrow B, and the aspirated reagent is discharged to the reaction chamber 11. This reagent collection is repeatedly performed, and when the reagent in the container becomes smaller than the minimum lower limit amount that can be collected by the apparatus, the reagent collection in this container ends.

The liquid surface position Hn and the suction reagent amount Vn stored in the control unit 13 are plotted as shown in FIG. 4, for example, when the suction reagent amount is fixed in the container shown in FIG. When the liquid surface position is the cylindrical portion 3a of the container, the reagent suction amount V is 50 μl and the liquid surface position H is lowered by two pulses (1 pulse = 0.08 mm), and when the liquid surface position becomes the conical portion 3b of the container ( After the suction amount in FIG. 4 exceeds 400 μl, the liquid surface position H drops significantly and reaches the lowest lower limit position (the liquid surface position 20 pulses in FIG. 4).

The data in FIG. 4 shows that the relationship between the liquid level position in this container and the remaining amount of the reagent is a linear equation at the liquid level position (liquid level position 60 pulses or more) of the cylindrical portion 3a of the container as shown in FIG. The liquid level position of the conical portion 3b of the container (6 from the liquid level position 20 pulse)
(Up to 0 pulse) is represented by a quadratic equation. The approximation of this data is performed by any conventional method. In a container as shown in FIGS. 2 and 3, an accurate relational expression can be obtained by using an approximate expression that differs depending on the liquid surface position. If the relational expression is obtained in this manner, the next time the same type of container is used, the remaining amount of the reagent is accurately calculated using the relational expression when collecting the reagent.

Further, since the remaining amount of the reagent is not known at the time of the first measurement, it is possible to provide an operation for obtaining only the relational expression, that is, a function for obtaining the relational expression only by collecting the reagent. The use of expensive reagents at that time is costly, so that another liquid can be put in an empty container.

However, since the liquid may adversely affect the analyzer, it is necessary to select the type of liquid and then put the liquid into the container. Therefore, if a liquid supply means for dispensing a liquid such as a diluting liquid or a washing liquid connected to the analyzer is provided in the container, the liquid is dispensed into an empty container that has been set, and the relational expression is automatically obtained. Actions can be taken. If the liquid supply means is provided, the relational expression between the liquid surface position and the residual liquid amount is obtained by using the liquid dispensed amount dispensed into the container by the liquid supply means instead of the liquid collection amount collected from the container. It is also possible to obtain the relational expression while dispensing the liquid.

Next, a description will be given of the detection of the residual liquid amount at the time of measurement by the analyzer in which the relational expression between the liquid surface position in the container and the residual liquid amount is input. First, the type of the reagent container to be used is input to the input unit 14. Then, when reagent collection is started, when the nozzle 4 rotates to the position of the container, descends into the container and comes into contact with the reagent liquid surface, the liquid surface position h is detected by the liquid surface sensor 15. The liquid level h is stored in the control unit 13.

The liquid level position h is input to the relational expression between the liquid level position corresponding to this container and the remaining liquid amount stored in the control unit 13 to calculate the reagent remaining amount v. This reagent remaining amount v is displayed on a CRT or the like of the output unit 18. Further, when the number of measurements input from the input unit 14 exceeds the remaining amount v of the reagent, an alarm display indicating that the reagent is exhausted during the measurement can prevent the trouble.

When the liquid in the container is sampled and the remaining liquid amount is detected by using a relational expression for obtaining the liquid surface position and the remaining liquid amount in the type of the container, the liquid surface position before and after the liquid collection is determined. By providing a comparing means for comparing whether the collected liquid amount matches the above-mentioned relational expression, whether the liquid surface position change accompanying the actual liquid collection changes according to the relational expression for obtaining the remaining liquid amount Can be checked. If the two do not match, an erroneous operation such as an input error of the container type may occur, so that an erroneous operation can be prevented by issuing a warning.

In some containers, even if they are of the same type, the dispersion may be large. In that case, the error of the residual liquid amount detected by the relational expression increases. Therefore, by providing an arithmetic function for correcting the above-mentioned relational expression so that the liquid level before and after the liquid collection coincides with the collected liquid amount, the remaining liquid amount can be detected with high accuracy. For example, if the liquid level position is less than 5% as compared with the relational expression, it is used as it is within the range of the error, and 5% or more and 20% or more.
If the difference is less than the relational expression, the relational expression can be corrected and corresponded, and if a difference of 20% or more occurs, a warning can be issued that the possibility of erroneous operation is high.

[0027]

According to the present invention, an analyzing apparatus which can accurately detect the amount of liquid remaining in a container by a single liquid sampling operation with a simple configuration, regardless of the shape of the container, can be obtained. Can be provided. Further, by providing a relational expression calculating means between the liquid level position in the container and the residual liquid amount, the analyzer can obtain the relational expression without knowing the relational expression. Further, by providing the liquid collecting means, it is possible to automatically obtain this relational expression only by setting an empty container.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory view showing an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing an example of a reagent container applied to the embodiment.

FIG. 3 is a longitudinal sectional view showing another example of the reagent container applied to the embodiment.

FIG. 4 is a graph illustrating a liquid level position and a suction amount according to the embodiment.

FIG. 5 is a graph illustrating a liquid level position and a residual liquid amount according to an example.

[Explanation of symbols]

 Reference Signs List 1 Table 2 Electrode 3 Reagent container 4 Nozzle 5 Arm 6 Shaft 7 Drive device 8 Tube 9 Syringe 10 Stepping motor 11 Reaction chamber 12 Conveyor 13 Control unit 14 Input unit 15 Liquid level sensor 16 Stepping motor 17 Stepping motor 18 Output unit

Claims (5)

[Claims] 1. A liquid collecting means for collecting a liquid contained in a container, a liquid surface position detecting means for detecting a liquid surface position in the container, and a container type input means for inputting a type of the container containing the liquid to be collected. And a relational expression storage means for storing in advance a relational expression between the liquid level position and the remaining liquid amount in each container type, and the liquid level position detected by the liquid level detection means and the input by the container type input means. An analyzer for detecting a residual liquid amount in a container by using the relational expression corresponding to a container type. 2. A relational expression between a liquid level position in a container and a residual liquid amount based on an amount of liquid collected from the container by the liquid collecting means and a liquid level position in the container detected by the liquid level position detecting means. And a relational expression calculated by the relational expression calculation means, the container type input by the container type input means, and the liquid level detected by the liquid level position detection means. 2. The analyzer according to claim 1, wherein the amount of the liquid remaining in the container is detected. 3. A liquid supply means for dispensing a liquid into a container, wherein the liquid supply means supplies the liquid to the container and has a function of calculating a relational expression between the liquid surface position and the remaining liquid amount. 3. The analyzer according to claim 2, wherein: 4. A comparison is made as to whether the amount of liquid collected by the liquid collecting means and the liquid level before and after the liquid level detected by the liquid level detecting means match the relational expression for detecting the residual liquid amount. 2. The analyzer according to claim 1, further comprising a comparison unit that performs the comparison. 5. When the amount of liquid collected by the liquid collecting means and the liquid level before and after the liquid level detected by the liquid level detecting means do not coincide with the relational expression for detecting the residual liquid amount, The analyzer according to claim 4, further comprising an arithmetic function for correcting the relational expression so as to match the detected liquid level position.