JP3815322B2 - Sample introduction device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sample introduction apparatus for introducing a sample into a liquid chromatograph, and particularly suitable for sampling a liquid in an industrial process line periodically or continuously and introducing it into a liquid chromatograph. It is about.
[0002]
[Prior art]
FIG. 2 shows the configuration of a conventional sample introduction apparatus. That is, the sample is supplied to the flow-through vial 1 periodically or continuously, and the sample suction needle 2 at the tip of the sample suction tube 3 is inserted into the vial 1 when the sample is sucked. At this time, the six-way valve 4 and the switching valve 5 are in the state of the solid line shown. Accordingly, when the syringe pump 6 of the metering pump is operated for suction, a certain amount of the sample is sucked and filled into the sample loop 7 via the sample suction needle 2 and the sample suction tube 3. Thereafter, when the flow path (position) of the hexagonal valve 4 is switched to the broken line shown in the figure, the sample in the sample loop 7 is pushed out together with the mobile phase solvent sent from the liquid feeding pump 8 and passes through the hexagonal valve 4. It is sent to the column 9 for separation and analysis. Reference numeral 10 denotes an appropriate detector. When the analysis is completed, the flow path of the hexagonal valve 4 is switched again to the position of the solid line.
[0003]
By the way, when the sample introduction is completed, the sample suction needle 2 is moved to above the cleaning port 11 disposed at an appropriate position, and remains in the sample suction tube 3 by discharging the syringe pump 6. The sample is discharged to the washing port 11.
[0004]
Further, after the remaining sample in the sample suction tube 3 is discharged, the switching valve 5 is switched from the position shown by the solid line to the position shown by the broken line, and the flow path connected to the vial 12 for the cleaning liquid is connected to the syringe pump 6, Then, the cleaning liquid is sucked into the pump 6 by the suction operation 6, and then the switching valve 5 is switched again to the position of the solid line shown in the drawing, and the cleaning liquid is sampled via the hexagonal valve 4 by discharging the syringe pump 6. The channel 7 is pushed out to the loop 7 and the sample suction tube 3 to clean the flow path.
[0005]
[Problems to be solved by the invention]
In the conventional sample introduction device, the sample suction needle (sample suction tube) is moved to each position of the vial to which the sample is supplied, the washing port, and several kinds of standard solutions (vials) prepared as necessary. Therefore, there is a problem that an XYZ 3-axis drive mechanism is required and the apparatus becomes large.
The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a sample introduction device that does not require movement of a sample suction needle and therefore does not require a triaxial drive mechanism.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, in the sample introduction apparatus of the present invention, the present invention comprises: a sample suction tube, a pump for measuring a sample, a sample loop for filling a fixed amount of the sample, and two positions where these are connected. It has a hexagonal valve, and after a sample is filled into the sample loop through the sample suction tube and hexagonal valve by the suction operation of the metering pump, the flow path of the hexagonal valve is switched to analyze the sample in the sample loop. In the liquid chromatograph sample introduction apparatus, a flow path switching valve having a common flow path connected to the hexagonal valve and a plurality of connection ports is provided in the middle of the sample suction tube, and the flow path switching valve A plurality of flow paths connected to the connection port and the metering pump, a six-way valve or a six-way valve via a common flow path of the flow path switching valve, To be connected via a Npururupu, characterized in that the sample to one of the connection ports of the flow path switching valve connects the recycle flow path for returning to the original process line. The flow path switching valve is composed of a rotary valve having a plurality of connection ports. In addition to the sample suction tube, the flow path connected to the drain flow path and the calibration standard solution vial is connected to the plurality of connection ports of the rotary valve. Any one or two or more flow paths are connected.
[0007]
In the sample introduction apparatus configured as described above, the sample suction tube (sample suction needle) is fixed in a state where it is inserted into a flow-through vial to which the sample is supplied, and the sample is sucked and the remaining sample is discharged. Recycle to the process line, suction and discharge of calibration standard solution, etc., selectively connect each flow path to multiple connection ports of flow path switching valve provided in the middle of the sample suction tube It can be performed only by the flow path selection operation of the switching valve.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic view of a sample introduction apparatus of the present invention.
A sample (liquid) is supplied from an industrial process line (not shown) to a flow-through vial 1 periodically or continuously, and the vial 1 has a sample suction needle 2 at the tip of a sample suction tube 3. Always inserted and fixed. The sample suction tube 3 is provided with a rotary valve 13 in the middle thereof. That is, the rotary valve 13 has one common flow channel connected to the hexagonal valve 4 and, for example, four connection ports, and one connection port has the other end of the sample suction tube 3 connected to the sample suction needle 2. Connected to the remaining three connection ports are a drain channel 14, a recycling channel 15 for returning the sample to the original process line, and a channel 16 connected to the calibration standard vial 17 respectively. Therefore, one common flow channel connected to the hexagonal valve 4, the sample suction tube 3, and the respective flow channels 14, 15, 16 can be selectively connected by operating the rotary valve 13.
[0009]
In addition to the flow path connected to the common flow path of the rotary valve 13, the hexagonal valve 4 is connected to both ends of the sample loop 7, a flow path connected to the syringe pump 6 via the switching valve 5, and a liquid feed pump 8. The flow path and the flow path connected to the column 9 are connected to each other, and switching between two positions indicated by the solid line and the broken line shown in the figure is possible.
[0010]
For sample suction, the other end of the sample suction tube 3 connected to the common flow path of the rotary valve 13 and the sample suction needle 2 is connected. At this time, the six-way valve 4 and the switching valve 5 are in the state of the solid line shown in the figure. Accordingly, the sample supplied to the vial 1 periodically or continuously by the suction operation of the syringe pump 6 of the metering pump passes through the sample suction needle 2, the sample suction tube 3, the rotary valve 13, and the hexagonal valve 4. Then, the sample loop 7 is sucked and filled with a certain amount. Thereafter, when the position of the hexagonal valve 4 is switched to the position of the broken line shown in the figure, the sample in the sample loop 7 is pushed out together with the mobile phase solvent sent from the liquid feeding pump 8 and sent to the column 9 through the hexagonal valve 4. The separated liquid composition is detected by the detector 10.
[0011]
On the other hand, when the sample introduction is completed, the common flow path of the rotary valve 13 is connected to the connection port with the drain flow path 14 during the analysis. Therefore, the sample remaining in the flow path to the rotary valve 13 is discharged to the drain flow path 14 by discharging the syringe pump 6. Further, when the rotary pump 13 is operated to select the connection between the common flow path and the connection port of the recycle flow path 15 and the syringe pump 6 is discharged, it remains in the flow path to the rotary valve 13. The sample can be returned to the original process line.
[0012]
When the analysis is completed, the position of the hexagonal valve 4 is switched from the position indicated by the broken line to the position indicated by the solid line. On the other hand, after the remaining sample in the sample suction tube 3 is discharged from the drain channel 14 or returned from the recycling channel 15 to the original process line, the switching valve 5 is moved from the position shown by the solid line to the position shown by the broken line. The flow path connected to the vial 12 for switching and the cleaning liquid is connected to the syringe pump 6, and the cleaning liquid is sucked into the pump 6 by the suction operation of the syringe pump 6. Thereafter, the common flow path of the rotary valve 13 is connected again to the connection port with the drain flow path 14, and the switching valve 5 is switched to the position of the solid line again to cause the syringe pump 6 to perform the discharge operation so that the cleaning liquid flows into the six-way valve 4. Via, the sample loop 7 is pushed out to the drain flow path 14 of the rotary valve 13 to clean the flow path.
[0013]
When calibration is performed using a standard solution, the common flow path of the rotary valve 13 is connected to a connection port with the flow path 16 connected to the vial 17 for the calibration standard liquid. At this time, the six-way valve 4 and the switching valve 5 are in the state of the solid line shown. Accordingly, by aspirating the syringe pump 6, a certain amount of the standard solution in the vial 17 is sucked and filled into the sample loop 7 via the rotary valve 13 and the hexagonal valve 4. Thereafter, the position of the hexagonal valve 4 is switched to the position of the broken line shown in the figure, and the sample in the sample loop 7 is pushed out together with the mobile phase solvent sent from the liquid feed pump 8 and sent to the column 9 through the hexagonal valve 4. Separation and analysis for calibration are performed.
[0014]
【The invention's effect】
Since the present invention is configured as described above, the sample suction needle at the tip of the sample suction tube can be fixed in a state of being inserted into the vial to which the sample is supplied. A large triaxial drive mechanism for moving to the position can be omitted. In addition to sample suction, residual sample discharge, calibration standard solution suction and discharge, etc., recycling of the residual sample back to the original process line can be performed with a simple rotary valve channel selection operation. it can.
[Brief description of the drawings]
FIG. 1 is a schematic view of a sample introduction apparatus according to the present invention. FIG. 2 is a schematic view of a conventional sample introduction apparatus.
1: Vial 2: Sample suction needle 3: Sample suction tube 4: Six-way valve 5: Switching valve 6: Syringe pump 7: Sample loop 8: Liquid feed pump 9: Column 13: Rotary valve 14: Drain flow path 15: Recycle Channel 16: Channel connected to the vial of standard solution

Claims (2)

It has a sample suction tube, a pump for metering the sample, a sample loop for filling the sample with a certain amount, and a two-position six-way valve to which these are connected. In a sample introduction device for a liquid chromatograph in which a sample loop is filled and then the flow path of the hexagonal valve is switched to introduce the sample in the sample loop into the analysis flow path. A flow path switching valve having a common flow path connected to the hexagonal valve and a plurality of connection ports is provided and a plurality of flow paths connected to the connection port of the flow path switching valve and the metering pump are connected to the flow path switching valve. It is possible to connect via a common flow path via a six-way valve, a six-way valve, or a sample loop. Sample introduction apparatus characterized by connecting the recycle flow path for returning to the original process line the sample One. The flow path switching valve is composed of a rotary valve having a plurality of connection ports. In addition to the sample suction tube, the flow path connected to the drain flow path and the calibration standard solution vial is connected to the plurality of connection ports of the rotary valve. 2. The sample introduction device according to claim 1, wherein any one or two or more flow paths are connected.

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