JP2553064B2 - Dispensing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial field of application) The present invention is equipped in an automatic chemical device for chemically analyzing a test sample (liquid) such as serum or urine using a spectrometer or the like. The present invention relates to a dispenser, and more particularly, to a dispenser that prevents non-specific mixture of different liquids.

(Prior Art) Generally, this type of automatic chemical analyzer has a structure as shown in FIG. That is, in FIG. 5, a plurality of reaction tubes (cells) 1a are annularly arranged in a turntable type reaction line 1 which intermittently moves by a predetermined angle. A plurality of reagent containers 2a are provided on one side of the reaction line 1.
Are arranged side by side, a test sample tray 3 in which a plurality of test sample containers 3a are arranged, and a probe cleaning unit 4 are arranged in parallel.

These reaction line 1, reagent tray 2 and test sample tray
3. An arm 5 is bridged above the probe cleaning unit 4, and a moving block 6 that is moved in its longitudinal direction by a drive mechanism (not shown) is provided on the arm 5. The moving block 6 is provided with a sample probe 7a of the dispensing device 7. The probe 7a is moved up and down by an unillustrated probe ascending / descending driving unit provided in the moving block 6.

Further, on the other side of the reaction line 1, there is provided a spectrometer 8 including a light source 8a, a spectroscopic unit 8b equipped with a detector, etc., and optically analyzes the progress of the reaction of the reaction solution in the reaction tube 1a. Then
It is designed to output as an analog signal. The output of the spectrometer 8 is converted into a digital signal by the A / D converter 9, taken into the CPU (computer) 10, and the analysis data is calculated by a predetermined calculation method.

CPU 11, display 11, printer 12 and operation panel
13 are connected. In addition, this automatic chemical analyzer
A constant temperature bath 14 of hot water for keeping the reaction tube 1a at a predetermined temperature,
A washing / drying unit 15 for washing / drying the reaction tube 1a, a reagent pump 16 and the like are provided. The CPU 10 controls the rotation operation of the reaction line 1, the movement operation of the arm 5 and the movement block 6, the movement operation of the trays 2 and 3, the operation of the dispensing device 7, etc. by a control program stored in the storage unit. It is done by execution. This control program is a program for the movement operation of the movement block 6, the dispensing device 7
And various programs such as a program for operating the pump, a program for operating the spectroscopic system 8 and a program for operating the signal processor.

The operation of the device shown in FIG. 5 is as follows. That is, by executing the control program of the CPU 10, the arm 5,
When the moving block 6 and the dispensing device 7 operate, the test sample in one test sample container 3a in the test sample tray 3 is dispensed into the reaction tube 1a, and then the reagent in the reagent container 2a is transferred. The reaction liquid is obtained by being discharged into the reaction tube 1a. The reaction tube 1a containing this reaction liquid moves to the spectrometer 8 where spectroscopic analysis is performed, and the CPU 10 obtains the analysis result.

FIG. 6 shows an example of the operation of the conventional dispensing device in FIG. 5, and FIG. 6 (a) is a diagram showing a suction operation, FIG.
FIG. 6B is a diagram showing the ejection operation.

In FIG. 6, as shown in FIG. 6 (a), the probe 7a is lowered into the reagent container 2a so that the probe end portion penetrates below the liquid surface (penetration value h), and a predetermined amount of reagent is aspirated. To do. Next, the probe 7a is raised and moved to the reaction tube 1a side. Here, as shown in FIG. 6 (b), the probe 7a
The probe end is infiltrated below the liquid surface of the reaction tube 1a by lowering, and the reagent of the probe 7a is discharged.

Here, the penetration value h is generally set by the amount of ascending / descending from a fixed position when the probe is ascending / descending, and more specifically, by the program control of the probe ascending / descending drive unit by the CPU 10.

Here, in the case of suction, since the liquid level in the reagent container 2a goes down with suction, the probe penetration value h is a value based on the suction amount (suction amount / suction amount /
It is necessary to set the cross-sectional area of the reagent container 2a) to a certain large value defined by h0 + tolerance α. On the other hand, in the case of discharging, for the reason such that the liquid is discharged without stopping in the reaction tube 1a, the probe 7a is placed below the liquid surface in the reaction tube 1a in the same manner as the above suction. Must be infiltrated.

For the above reason, the amount of ascending / descending of the probe 7a is set to the value h in the suction operation that does not cause any inconvenience in ascending / descending of the liquid level.

However, in this case, the reagent Lq other than the fixed amount adhering to the outer surface of the probe 7a when entering the reagent container 2a is brought into the reaction tube 1a, and the liquid level in the reaction tube 1a The reagent Lq outside the fixed amount is
It mixes with the test reagent inside. This impairs the microdispensing function required for this type of dispensing device, and
The concentration of the reaction solution generated in 1a also became inaccurate, which in turn was a factor of deteriorating the analysis characteristics of the analyzer.

(Problems to be Solved by the Invention) As described above, in the conventional technique, the probe penetration value is set according to the amount of ascent and descent from the fixed position when the probe ascends and descends, so the penetration value during suction is large. As a result, the non-quantitative liquid adhering to the outer surface of the probe during suction is mixed in during ejection, resulting in the out-of-specification mixing of different liquids, which is a problem.

Therefore, it is an object of the present invention to provide a dispensing device that prevents out-of-specification mixing of different liquids.

[Structure of the Invention] (Means for Solving Problems) The present invention is configured as follows in order to solve the above problems and achieve the object. That is, according to the present invention, at least a probe capable of ascending and descending is used to aspirate the first liquid contained in the first container and dispense the aspirated liquid into the second container containing the second liquid. In the apparatus, a liquid level detection unit that detects that the tip of the probe has come into contact with the liquid surface to be measured is provided, and based on the detection signal of the liquid level detection unit, the tip of the probe is the second liquid when discharging. It is characterized in that it further comprises control means for controlling the infiltration value H2 that infiltrates into the liquid surface of (1) to be smaller than the infiltration value H1 in which the tip of the probe penetrates into the liquid surface of the first liquid during suction.

(Operation) By taking such a means, the tip of the probe is sucked by the liquid in the suction and discharge operations so that the suction operation of the first liquid and the discharge operation of the sucked first liquid into the second liquid can be performed smoothly. In this case, the probe penetration value H2 during ejection is controlled to be smaller than the probe penetration value H1 during suction, so that the non-quantified first liquid adhering to the second liquid on the outer surface of the probe during suction Mixing will be prevented as much as possible.

Further, by controlling the infiltration values H1 and H2 in the above relationship, the amount of the non-quantitative first liquid adhering to the outer surface of the probe at the time of suction can be reduced, and the second liquid of the non-quantitative first liquid can be reduced.
Mixing into the liquid is reduced, and the mixing amount of the non-quantitative first liquid into the second liquid is reduced as much as possible not only at the time of suction but also at the time of discharge, so that a small amount of dispensing can be performed with high accuracy.

(Embodiment) An embodiment of the dispensing device according to the present invention will be described below with reference to FIGS. 1 to 4.

FIG. 1 is a diagram showing the overall configuration of the present embodiment, FIG. 2 is a circuit diagram showing the details of the liquid level detection unit in the same embodiment, FIG. 3 is a flow chart showing the operating procedure of the same embodiment, and FIG. FIG. 7 is a diagram showing a suction / ejection operation in the same embodiment.

In FIG. 1, the probe 7a is configured to be capable of ascending / descending operation and parallel movement operation by the drive controller 17.
Further, this probe 7a is equipped with a liquid level detection unit 18 capable of detecting the distance between the liquid level and the end of the probe with an electric signal. Further, this probe 7a is piped to a dispensing syringe pump 19 as a drive source for suction and discharge, and further, this dispensing syringe pump 19 is piped to a syringe pump 21 and a water tank 22 via a three-way switching valve 20. ing.

Here, the liquid level detection unit 18 has a structure as shown in FIG. 2 as described in the specification and drawings of Japanese Patent Application No. 61-63075 filed by the applicant of the present application prior to the present application. ing. That is, as shown in FIG. 2 (a), three fixed resistors R1, R2, R3 and a variable capacitor C are configured as a bridge circuit, an AC power source P is connected to this bridge circuit, and the variable capacitor of the bridge circuit is connected. The configuration is such that the impedance change due to the capacitance change of C is obtained and led to the signal processing system. Here, the variable capacitor C is shown in FIG.
As shown in, it is configured as a capacitor based on a change in stray capacitance between the reagent container 2a or the reaction tube 1a and the probe 7a. With this configuration, a large impedance change appears when the probe 7a comes into contact with the liquid surface, and this change can be detected by an electric signal.

Here, regarding the ascending / descending operation of the probe 7a, in the drive control unit 17, based on the detection signal from the liquid level detection unit 17, the penetration value H2 to the liquid level in the reaction tube 1a at the tip of the probe 7a at the time of discharge, It is set to be smaller than the penetration value H1 of the tip of the probe 7a with respect to the liquid surface of the reagent container 2a at the time of suction, where the penetration value H2 is the reaction tube at the tip of the probe 7a.
The minimum value that does not separate from the liquid surface of 1a is set to, for example, about 0.5 mm. The penetration value H1 is set to be, for example, about 5 mm.

Next, the operation of the apparatus of this embodiment configured as described above will be described. That is, as shown in FIGS. 1 and 3 (a), the probe 7a is located in the reagent container 2a in the initial state. Here, as shown in FIG. 3 (a), the process A1
As a result, the drive control of the drive control unit 17 causes the probe 7a to descend. Then, as the process A2, when the probe 7a comes into contact with the liquid surface of the reagent container 2a, the detection is detected by the liquid surface detection unit 18, and the detection signal is given to the drive control unit 17. here,
There is an interval, whereby the penetration value H1 of the probe 7a with respect to the liquid surface of the reagent container 2a becomes about 5 mm,
As process A3, the probe descent is stopped. This state is the fourth
It is shown in FIG. Then, as the process A4, when the dispensing syringe pump 19 is sucked by the pump driving device (not shown), a predetermined amount of reagent is sucked into the dispensing syringe pump 19 and the probe 7a is raised. Here, the three-way switching valve 20, syringe pump 21, water tank 22
The water in 22 is extruded into the syringe pump 19 and sucked as water.

Next, in FIG. 1, the probe 7a moves and is positioned above the reaction tube 1a by the drive control of the drive control unit 17. Then, as the process B1 in FIG. 3B, the probe 7a descends. Here, as the process B2, when the probe 7a comes into contact with the liquid surface of the reaction tube 1a, the detection is detected by the liquid surface detection unit 18,
The detection signal is given to the drive controller 17. Here, an interval is set, whereby the penetration value H2 of the probe 7a with respect to the liquid surface of the reaction tube 1a becomes about 0.5 mm, and the treatment B
As a result, the probe will stop descending. This state is shown in FIG. 4 (b). Then, as the process B4, when the dispensing syringe pump 19 is discharged by a pump drive device (not shown), the reagent and the extruded water in the dispensing syringe pump 19 are discharged to the liquid (test sample) in the reaction tube 1a. .

After the above operation, the water in the water tank 22 is transferred to the syringe pump 19 by the three-way switching valve 20, the syringe pump 21, and the water tank 22.
It is sucked into the inside as washing water, and the probe 7a, the dispensing syringe pump 19 and the pipe are washed.

According to the present embodiment as described above, regarding the ascending / descending operation of the probe 7a, the drive control unit 17 is based on the detection signal from the liquid level detection unit 17, and in the reaction tube 1a at the tip of the probe 7a at the time of ejection. The penetration value H2 for the liquid surface is the penetration value for the liquid surface of the reagent container 2a at the tip of the probe 7a during suction.
It is set to be smaller than H1, where the penetration value H2 is set to a value of, for example, about 0.5 mm as a minimum value at which the tip of the probe 7a does not separate from the liquid surface of the reaction tube 1a.
Further, since the penetration value H1 is set to be, for example, about 5 mm, the non-quantitative reagent adhering to the outer surface of the probe 7a when entering the reagent container 2a,
Mixing into the liquid in the reaction tube 1a is prevented as much as possible. Therefore, the concentration of the reaction liquid generated in the reaction tube 1a becomes accurate without impairing the trace amount dispensing function required for this type of dispensing device, and the analytical characteristics of the dispensing device are improved. .

The present invention can be implemented by modifying it as follows. That is, in the above embodiment, after the liquid level is detected by the liquid level detector 18, the infiltration value is fixedly set by the drive controller 17, but the infiltration value is set in conjunction with the rise and fall of the liquid level. The configuration may be adjusted. According to this configuration, the probe 7a is subjected to a predetermined suction / ejection operation, unnecessary liquid is prevented from adhering to the outside of the probe 7a as much as possible, and unnecessary mixing of the adhered liquid is prevented as much as possible. .

The present invention discloses a configuration for preventing non-specified liquid from adhering to the outside of the probe 7a during suction / ejection, and the configuration of the liquid level detection unit, the type of fluid equipment to be applied, etc. are limited. Not something.

[Effects of the Invention] As described above, according to the present invention, at least a probe capable of moving up and down is used to suck the first liquid contained in the first container, and the suction liquid is contained in the second liquid. In the dispensing device for discharging to the second container, a liquid level detection unit is provided for detecting that the tip of the probe is in contact with the liquid level to be measured,
Penetration value at which the tip of the probe penetrates into the liquid surface of the second liquid during ejection based on the detection signal of the liquid surface detection unit
By providing a control means for controlling H2 to a value smaller than the penetration value H1 at which the tip of the probe penetrates into the liquid surface of the first liquid during suction, the suction operation of the first liquid and the sucked first liquid The tip of the probe is made to penetrate below the liquid surface in the suction and discharge operations so that the discharge operation into the second liquid can be smoothly performed.
Since H2 is controlled to be smaller than the probe penetration value H1 during suction, mixing of the first liquid, which is not fixed in quantity, adhered to the outer surface of the probe during suction into the second liquid is prevented as much as possible.

Further, by controlling the infiltration values H1 and H2 in the above relationship, the amount of the non-quantitative first liquid adhering to the outer surface of the probe at the time of suction can be reduced, and the second liquid of the non-quantitative first liquid can be reduced.
Mixing into the liquid is reduced, and the mixing amount of the non-quantitative first liquid into the second liquid is reduced as much as possible not only at the time of suction but also at the time of discharge, so that a small amount of dispensing can be performed with high accuracy.

Therefore, according to the present invention, it is possible to provide a dispensing device in which different types of liquid are prevented from being mixed out of the prescribed range.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall configuration of an embodiment of the present invention, FIG. 2 is a circuit diagram showing details of a liquid level detection unit in the embodiment, and FIG. 3 is a flow chart showing an operating procedure of the embodiment. FIG. 4 is a diagram showing a suction / ejection operation in the same embodiment, FIG. 5 is a general configuration diagram of an automatic chemical analyzer to which the present invention is applied, and FIG. 6 is a diagram illustrating a configuration of a conventional example. . 1 ... reaction line, 1a ... reaction tube, 2 ... reagent tray,
2a ... Reagent container, 3 ... Test reagent tray, 3a ... Test reagent container, 4 ... Probe washing section, 5 ... Arm, 6 ...
Moving block, 7 ... Dispensing device, 7a ... Sample probe, 8 ... Spectrometer, 9 ... A / D converter, 10 ... CPU, 11 ...
… Display, 12 …… Printer, 13 …… Operating panel,
14 ... Constant temperature bath, 15 ... Washing / drying unit, 16 ... Reagent pump, 17 ... Drive control unit, 18 ... Liquid level detection unit, 19 ...
Dispensing syringe pump, 20 …… 3-way switching valve, 21 …… Syringe pump, 22 …… Water tank.

Claims (3)

(57) [Claims] 1. A dispensing device for sucking a first liquid contained in a first container by a probe and discharging the sucked liquid to a second container containing a second liquid, wherein a tip of the probe is an object to be measured. Provided with a liquid surface detection unit that detects contact with the liquid surface,
Based on the detection signal of the liquid level detector, the penetration value H2 at which the tip of the probe penetrates into the liquid level of the second liquid during ejection.
Is provided with a control means for controlling the tip of the probe to a value smaller than the penetration value H1 at which the tip of the probe penetrates into the liquid surface of the first liquid during suction. 2. The injecting value H2 at which the tip of the probe infiltrates into the liquid surface of the second liquid during ejection,
The dispensing device according to claim 1, further comprising means for executing a control operation for setting a minimum value at which the tip end portion of the probe does not separate from the liquid surface of the second liquid. 3. The liquid level detection unit detects a change in amplitude and phase of a signal associated with a change in impedance caused by the presence or absence of contact between the tip of the probe and the liquid level of the first and second liquids. The dispensing device according to claim 1 or 2, further comprising means for obtaining a liquid level detection signal.