JP3896842B2 - Flame atomic absorption spectrophotometer - Google Patents

Description

[0001]
[Field of the Invention]
The present invention relates to an atomic absorption spectrophotometer, and more particularly to a flame atomic absorption spectrophotometer that atomizes a sample by introducing an atomized sample solution into a chemical flame.
[0002]
[Prior art]
In an atomic absorption spectrophotometer, it is necessary to vaporize a sample. Atomization methods include a flame method using a chemical flame and a flameless method not using a chemical flame. FIG. 2 shows a schematic configuration diagram of a flame type atomic absorption spectrophotometer. FIG. 3 shows a schematic configuration diagram of a conventional premixed atomization unit 23. A nebulizer 32 is supported by a nebulizer support 40 on one end side of the chamber portion 30, and a capillary tube 31 is fitted into the nebulizer 32. When an auxiliary combustion gas such as air supplied to the nebulizer 32 is ejected through the auxiliary combustion gas pipe 33, the sample solution is sucked up through the capillary pipe 31 by the negative pressure. The sample solution is sprayed with an auxiliary combustion gas, mixed with a combustion gas such as acetylene gas supplied through the combustion gas pipe 34, and blown out into the chamber 30. This mixed gas is ejected from a slot portion 38 of a burner head 37 provided at the upper portion on the other end side of the chamber portion 30, and a sample component is atomized in a frame 39 formed thereby. In addition, not only the said structure but a combustion gas can be introduce | transduced from the appropriate position in the chamber part 30. FIG.
[0003]
The light emitted from the light source 21 is absorbed by the atomized portion 23 by the sample atomized in the frame. The light from the light source 21 that has passed through the atomization unit 23 is split by the spectroscope 25, and only the wavelength at which the atomized target sample exhibits absorption is extracted, and the intensity is measured by the detector 27. The light intensity measured by the detector 27 is sent to the signal processing unit 28, and the amount of the target component contained in the sample is calculated from the light absorption amount in the atomization unit 23, and the result is shown on the display unit 29. It is.
[0004]
[Problems to be solved by the invention]
When the flame is ignited in the atomization unit 23, combustion gas is introduced into the chamber unit 30 and the frame is ignited. However, there is an incomplete installation of components such as the nebulizer 32 and the combustion gas pipe 34 installed in the chamber unit 30. In some cases, the combustion gas introduced into the chamber part 30 may flow out of the part where the parts are not attached to the outside of the chamber part 30, and due to an increase in the pressure inside the chamber part 30 when the flame is ignited, There is a risk of sudden disengagement, a risk of backfire in which the frame 39 of the burner head 37 wraps around the chamber portion 30 when the flame is ignited, and a risk of fire from a part that is improperly mounted when a backfire occurs.
[0005]
In the prior art, in order to prevent the danger at the time of flame ignition in the atomization unit 23 in advance, position detection sensors are provided for all the components mounted on the chamber unit 30, and the positions of all the components are always set. Is being monitored. For this reason, the structure of the whole apparatus becomes complicated and causes a cost increase.
[0006]
In addition, when a position sensor of a component fails, there is a possibility that it is determined that the component is installed correctly due to erroneous detection of the sensor even though the component is not installed correctly. The dangers mentioned above can occur. Therefore, in order to reliably prevent danger at the time of flame ignition, it is necessary to inspect the position detection sensor itself. However, this inspection must be performed for each component to which the position detection sensor is attached. The more sensors, the more time is required.
[0007]
The present invention has been made to solve the above problems, and provides a frame-type atomic absorption spectrophotometer that can easily detect mounting defects of components mounted in a chamber portion with a simple structure. Objective.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, the flame atomic absorption spectrophotometer of the present invention comprises means for supplying combustion gas, atomization means for atomizing the sample, and waste liquid means for discharging the excess of the sample. In the frame type atomic absorption spectrophotometer having a chamber portion, a float floating on the liquid surface of the waste liquid means and a means for detecting the float are provided, and a photo sensor detects the float when gas is supplied into the chamber. When the gas is not supplied, the photo sensor does not detect the floating.
[0009]
If there are imperfect installations in the parts installed in the chamber, the pressure in the chamber will be lower when a certain pressure is applied in the chamber than in the normal case. By doing so, it is possible to easily detect the presence or absence of mounting defects of the components mounted in the chamber portion.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view of an atomization section of a frame-type atomic absorption spectrophotometer according to the present embodiment. From the chamber section 1, the nebulizer 3, the gas introduction section 5, the burner head 7, the safety plug 9, and the drain tube 11. It is configured. The burner head 7 is provided with a slot portion 8, and the drain tube 11 is provided with a float 12 and a photosensor 13.
[0011]
Next, the operation will be described. The drain tube 11 is filled with water, and is sealed so that the pressure in the chamber portion 1 does not leak outside. The float 12 moves in the drain tube 11 together with the water level filled in the drain tube 11. The photo sensor 13 is installed outside the drain tube 11 in order to detect the position of the float 12. When parts such as the nebulizer 3, the gas introduction part 5, and the safety plug 9 are normally attached to the chamber part 1, when air of a constant pressure is introduced from the gas introduction part 5 into the chamber part 1, a part of the air is Although leakage from the slot portion 8 of the burner head 7 to the outside of the chamber portion 1 occurs, the inside of the chamber portion 1 becomes a steady state at a certain constant pressure if air is continuously supplied. At this time, the water level in the drain tube 11 is lowered due to the increase in pressure in the chamber portion 1, and at the same time the stopping position of the float 12 is lowered. By installing the photo sensor 13 at this stop position, the photo sensor 13 detects the float 12.
[0012]
When parts such as the nebulizer 3, the gas introduction part 5, and the safety plug 9 are not normally attached to the chamber part 1, when air of the same constant pressure is introduced into the chamber part 1 from the gas introduction part 5, a part of the air is Since the leakage from the slot portion 8 of the burner head 7 and the part inadequately mounted to the outside of the chamber part 1 occurs, the pressure in the chamber part 1 becomes lower than when the part is normally attached to the chamber part 1. Therefore, the water level in the drain tube 11 is not lowered as compared with the case where the component is normally mounted on the chamber portion 1, and the stopping position of the float 12 is higher than that when the component is normally mounted on the chamber portion 1. The photo sensor 13 does not detect the float 12. Therefore, when the photo sensor 13 does not detect the float 12, it can be confirmed that the components in the chamber portion 1 are not normally attached.
[0013]
In addition, if both the case where pressure is applied to the inside of the chamber portion 1 and the case where pressure is not applied are checked, it is possible to simultaneously confirm whether the components mounted in the chamber portion 1 are not properly mounted or the photosensor 13 is broken. FIG. 4 shows detection patterns of the photosensor 13 as to how to determine whether or not there is a component mounting defect and whether or not the photosensor 13 has failed due to a combination of the operation in these cases and the detection status of the photosensor 13.
[0014]
That is, the photosensor 13 detects the float 12 when a pressure is applied to the chamber portion 1, and then the chamber portion does not detect the float 12 when the pressure load into the chamber portion 1 is removed. It is possible to confirm that there is no mounting defect in the components in 1 and that the photosensor 13 is operating normally at the same time. In addition, when the pressure is applied to the chamber part 1 and then the pressure load to the chamber part 1 is removed, the photo sensor 13 is mounted on a component in the chamber part 1 unless the photo sensor 13 detects the float 12 in either case. There is a possibility that there is a defect or the photo sensor 13 has failed, and it is necessary to check the mounting state of parts in the chamber section 1 and the operating state of the photo sensor 13. Similarly, when pressure is applied to the chamber portion 1 and subsequently the pressure load to the chamber portion 1 is removed, if the photosensor 13 detects the float 12 in either case, it is attached to the component in the chamber portion 1. There is a possibility that there is a defect or the photo sensor 13 has failed, and it is necessary to check the mounting state of parts in the chamber section 1 and the operating state of the photo sensor 13.
[0015]
As mentioned above, although the Example of this invention was described, this invention is not limited to the said Example, A various change can be made within the range of the summary of this invention described in the claim. . For example, the float 12 and the photosensor 13 are used as means for monitoring the pressure in the chamber unit 1, but a pressure gauge may be attached to the chamber unit 1 to read the value.
[0016]
【The invention's effect】
According to the present invention, by applying a constant pressure in the chamber part and monitoring the applied pressure, it is possible to easily find out whether there is a mounting defect of the parts mounted in the chamber part. By simply adding a means for monitoring the pressure, the danger at the time of flame ignition in the atomization unit can be reliably prevented in advance, the entire apparatus can be simplified, and the cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view of an embodiment of an atomization unit used in a flame type atomic absorption spectrophotometer of the present invention.
FIG. 2 is a schematic configuration diagram of a conventional flame atomic absorption spectrophotometer.
FIG. 3 is a schematic configuration diagram of a conventional premixed atomization unit.
FIG. 4 is a diagram showing a detection pattern of a photosensor.
[Explanation of symbols]
1 --- chamber part 1
3-Nebulizer 5-Gas inlet 7-Burner head 8-Slot 9-Safety plug 11-Drain tube 12-Floating 13-Photo sensor

Claims (1)

In a flame type atomic absorption spectrophotometer having a chamber portion comprising means for supplying combustion gas, atomizing means for atomizing a sample, and waste liquid means for discharging the surplus of the sample, the liquid of the waste liquid means A float that floats on a surface and a means for detecting the float are provided, and a photosensor detects the float when gas is supplied into the chamber, and the photosensor does not detect the float when gas is not supplied. A flame type atomic absorption spectrophotometer.

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