JPS60128365A - Analyzing device - Google Patents

Abstract

PURPOSE:To obtain an analyzing device which holds the flow rate of a carrier constant even when the temperature of the carrier varies by controlling the rotating speed of a feed liquid pump to that the flow rate of the carrier is specific. CONSTITUTION:The elapsed time Ts1 from when a sample S1 is put in a reagent 1 through a smapling valve 9 to when the sample reacts and is led to a flow cell 9 to detect its position is measured. Similarly, the elapsed times Ts2... Ts6 from the supply points of samples S2, S3,...S6 to the detection points of their peak positions are measured. Thus, the elapsed time from the sampling point of each sample 5 to the detection point of the peak point of the sample is measured and when the time is varied, the number of pulses applied to a pulse motor which drives a reciprocal pump 2 is controlled by utilizing the proportion of the feed amount of the reagent 1 to the rotating speed of the pulse motor to hold the flow rate of the reagent 1 constant. Thus, the analysis precision is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application] The present invention relates to an analytical device, and particularly to an analytical device using flow injection analysis in which the carrier flow rate is controlled.

[Background of the invention]

A reciprocating pump is generally used as a carrier liquid pump for an analyzer using a flow injection analyzer. This pump operates at a constant rotation speed and stroke to change the flow rate of the carrier if air bubbles in the carrier adhere to the ball valve in the pump part or if the carrier or temperature changes and the viscosity changes. It has a drawback. This change in flow rate affects the shift in the chromatographic peak position or the peak height, causing errors in the measured values.

[Purpose of the invention]

The present invention has been made in view of the above, and its purpose is to keep the carrier and flow rate constant even when air bubbles in the carrier adhere to the carrier liquid feeding pump and the temperature of the carrier changes. The objective is to provide an analytical device that can perform

[Summary of the invention]

The characteristics of the present invention are as follows: from the time a sample is sampled by a sampling device to the time from when the component concentration of the sample is detected by a detector that detects the component concentration of the sample to the time when a chromatographic peak is detected; and a control means for controlling the rotational speed of the liquid feeding pump of the carrier so that the flow rate detected by the detection means always becomes a predetermined flow rate. .

[Embodiments of the invention].

The present invention will be described below with reference to the embodiments shown in FIG.
This will be explained in detail using Figure 4.

FIG. 1 is an overall configuration diagram showing an embodiment of the analysis device of the present invention, and shows an analysis device using flow injection analysis. In FIG. 1, a reagent 1 as a carrier is fed by a reciprocating pump 2 driven by converting rotation by a pulse motor into piston movement of a plunger, and is passed through a sampling valve 3 to an air constant temperature bath 7 at a constant temperature. and reaches 70-cell 9 in colorimeter 8. On the other hand, the sample 5 on the autosampler 4 is sucked by the suction pump 6 and guided to the sampling valve 3.

The sampling valve 3 is configured so that by rotating it, a certain amount of sampled sample 5 can be introduced into the reagent 1 being fed by the reciprocating pump 2, and the sample 5 is mixed with the reagent 1. The air flows into the thermostatic chamber 7, where it reacts and is led to the cell 70-9. The light from the light source 10 of the colorimeter 8 passes through the sample in the flow cell 9, is converted into monochromatic light by the spectrometer 11, and enters the photodetector 12.The output of the light detector 12 is logarithmically converted. 1. The output is sent to a control device 15 incorporating a microcomputer via an A-D controller 14.
Here, the data is processed to determine the chromatographic density, and the measurement results are printed on the printer 16.

By the way, in the present invention, the time when the sample 5F2 is introduced into the reagent 1 by the sampling valve 3 and the elapsed time from this time until the chromatographic peak is printed are also printed on the printer 16. This elapsed time corresponds to the flow rate of reagent 1.

Figure J@2 is a diagram showing the chromatographic peak position and elapsed time. From the time when the sample S1 is introduced into the reagent 1 through the sampling valve 3, the sample reacts and is guided to the 70-cell 9.
Elapsed time 'L' until the peak position is detected
Count 1. The same goes for the next samples 82, 83, . . . , 86, and the elapsed time Ts*eTis*·j−·J86 from the time of sample introduction until the peak position is detected is calculated.

In this way, the elapsed time from the sampling time of each sample 5 until the peak position of that sample is detected is calculated, and if that time changes, the amount of liquid fed for sample M1 is changed and the pro-bump 2 is driven. Since it is proportional to the number of rotations of the pulse motor, the number of pulses applied to the pulse motor is controlled to keep the flow rate of the reagent l constant. This makes it possible to improve the accuracy of analysis.

Next, a specific method for determining the above elapsed time will be explained. Here, it is realized using only microcomputer software without adding any hardware. Figure 3 below.

This will be explained in detail using FIG. FIG. 3 is a block diagram for explaining one embodiment of a method for detecting the carrier flow velocity. Inside the control device 15 of FIG. 1, as shown in FIG. Timer 1 that periodically generates an interrupt to the microcomputer 17
8. Element control device 19 that controls each component of the analyzer
, a pulse motor controller 20 for controlling a pulse motor which is a drive source of the reciprocating pump 2, and the like are provided.

) When the timer 18 generates an interrupt to the microcomputer 17 at a fixed period (10 mg in the embodiment), the microcomputer 17 adds 1 to the soft counter (internal memory) each time this interrupt occurs. When the value of the soft counter reaches a preset value C1, the sampling valve 3 is operated and the sample 5 is sampled. On the other hand, immediately after the operation of the sun-silling valve 3, the output signal of the photodetector 12 in the colorimeter 8 is taken into the microcomputer 17 by the A-D converter 14 every time a timer interrupt signal is generated via the logarithmic converter 13. . The value is Ht, H,...

Ha + Hm*t I When Hm*t, Ha*
When the condition of tHa<6 is reached, the temporal position becomes the peak position. The value of ε is set to a value larger than the noise of the measurement system by the colorimeter 8. Here, when the value (Cs Ct) obtained by subtracting the soft counter value C1 at the time the sampling valve 3 operates from the soft counter value C3 at the time the peak was detected is multiplied by the interrupt signal period T of the timer 18, the value is obtained. (Cs Ct)'T is
This is the time from when the sampling valve 3 is operated until the peak position of the sample 5 is detected at that time. Since the flow path volume from the sampling valve 3 to the cell 70 in the colorimeter 8 is constant, (Cs Ct )T is proportional to the flow rate of the reagent 1 sent by the reciprocating pump 2. . On the other hand, the memory in the microcomputer 17 stores in advance the theoretical value Tc of the elapsed time from the operation of the sampling valve 3 to the time of detection of the emergency, and the actual rotational speed of the pulse motor that is the drive source of the reciprocating pump 2. When is set as N1, N1-mouth(Cs-Ct)T Tc )/Tc
:] The value of Nt is calculated and this value is set in the pulse motor controller 920, thereby controlling the rotation speed of the reciprocating pump 2. In this way, the flow rate of the reciprocating pump 2 is constantly controlled by comparing it with the value Tc previously stored in the memory in the microcomputer 17, thereby obtaining a constant flow rate. In FIG. 4, (a) shows the timer interrupt signal, (b) shows the rotation of the sampling valve, and (C) shows the spectrometer output.

〔Effect of the invention〕

As explained above, according to the present invention, the flow rate of the carrier can be kept constant even if air bubbles in the carrier adhere to the carrier liquid feeding pump or the temperature of the carrier changes. .

[Brief explanation of the drawing]

- Figure 1 is an overall configuration diagram showing one embodiment of the analyzer of the present invention, Figure 2 is a diagram showing a chromatographic peak device and elapsed time, and Figure 3 is an implementation of a method for detecting the carrier flow rate. FIG. 4 is a block diagram for explaining an example, and a time chart for explaining the operation of FIG. 3. 1... Reagent (carrier), 2... Reciprocating pump, 3... Sampling valve, 4... Autosampler,
5... Sample, 6... Suction pump, 7... Air constant temperature bath, 8... Colorimeter, 9... Flow cell, 1o...
Light source, 11... Spectrometer, 12-... Photodetector, 13.
... Logarithmic converter, 14 ... A-D converter, 15
...Control device, 16...Printer, 17...Microcomputer, 18...Timer, 19...Element control device, 20...Pulse motor controller'2゜Representative Patent attorney Akio Takahashi

Claims (1)

[Claims] 1. A reagent, which is a carrier, is sent to a flow path system using a liquid pump, and a sample is sipped into the carrier using a sampling device in the middle of the flow path system to cause a reaction, and the sample is introduced into a flow cell for analysis of the sample. In the case where the sample is sampled by the sampling device, component concentration is detected by a probe that detects the component concentration of the sample, and a chromatographic peak is detected. a detection means for detecting the flow velocity of the carrier from the distance until the carrier reaches a predetermined flow rate; An analytical device characterized by comprising means and a device.