JP3052295B2 - Atomized sample introduction device for spectroscopic analysis - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spectroscopic analyzer of the type in which a sample solution such as a high-frequency inductively coupled plasma emission spectrometer is atomized and introduced into a sample atomization or excitation section, and particularly in an atomized sample introduction section. The present invention relates to a means for monitoring a spray amount of a sample solution.

[0002]

2. Description of the Related Art Conventionally, sample atomization is performed by atomizing a sample solution with a sample atomizer, and sending the atomized particles to a plasma torch or the like in a sample atomizing section by carrying the atomized particles on a carrier gas flow. A configuration has been used in which a light source and a light receiving element are arranged outside a pipe, with a glass pipe extending from a vessel to a sample atomization or excitation section such as a plasma torch or the like.

In the above-described conventional configuration, it is difficult to precisely control the amount of sprayed sample because droplets of the sample adhere to the inner surface of the glass tube and the tube wall fogs to change the sensitivity.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the above-mentioned drop in sensitivity and fluctuation in sensitivity due to the attachment of sample droplets to the optical path of the sample spray amount monitoring means.

[0005]

A light source and a light receiving element are arranged so as to directly face the inside of a glass pipe from a sample atomizer to a sample atomizing section or an excitation section, and the light source and the light receiving element are arranged in front of the light source and the light receiving element. In each case, an air curtain was formed by a carrier gas for transporting the sample mist.

[0006]

Since the light source and the light receiving element are disposed in the path of the atomized sample so as to be exposed, there is no loss due to the reflection and absorption of light by the glass in the conduit, and the adhesion of the sample droplet to the glass does not matter. In addition, since the air curtain is present on the front surface of the light-receiving element and the like and the droplet does not adhere, the sensitivity does not change.

[0007]

FIG. 1 shows an embodiment of the present invention. In the figure, 1 is a plasma torch, 2 is a sample atomizer, and 3 is a glass pipe for sending the sample atomized from the sample atomizer 2 to the plasma torch. The carrier gas is supplied to the sample atomizer 2 to suck and atomize the sample solution S, and the sample is sent to the plasma torch 1 through the glass pipe 3. The sample mist drops on the glass conduit 3 on the flow of the carrier gas, is sent into the plasma flame F formed at the tip of the plasma torch, is atomized at the high temperature of the plasma flame, and is further thermally excited. To emit light.
The plasma torch 1 is a triple tube, and the central tube 11 is an extension of the above-mentioned glass conduit 3 and surrounds the inner tube 12 for supplying a gas forming a plasma flame, and a cooling gas supply for cooling the plasma torch. Outer tube 13.

The glass pipe is provided with branch pipes 31 and 32 projecting horizontally in the middle so as to face left and right. The light source 4 is inserted into the right branch pipe 31 and the light is received by the branch pipe 32 on the opposite side. Element 5 has been inserted. With this arrangement, the light source 4 and the light receiving element 5 face each other across the flow of the carrier gas containing the sample mist without intervening glass. A carrier gas injection pipe 6 is provided on the lower surface of each of the branch pipes 31 and 32.
1, 62 are provided, and carrier gas is blown.
Since the branch ends 31 and 32 are closed by the light source 4 and the light receiving element 5, respectively, the carrier gas blown from 61 and 62 flows toward the central glass conduit 3, and the glass conduit 3
Merges with the flow of the carrier gas ascending inside. The flow of the carrier gas from the carrier gas injection pipes 61 and 62 toward the glass pipe 3 serves as an air curtain, which prevents the liquid droplets from adhering to the surfaces of the light source 4 and the light receiving element 5.

[0009]

According to the present invention, since the amount of spray is measured without passing through the glass of the glass conduit, the measurement can be performed without loss of light due to reflection and absorption of the glass wall, and the sensitivity can be improved. The function of the air curtain prevents fog droplets from adhering in the measurement optical path, so that there is no irregular fluctuation of sensitivity and sensitivity decrease, and a stable spray amount measurement can be performed over a long period of time. As a result, the accuracy of the control of the spray amount is improved and the quantitative accuracy in the analysis is improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a main part of an apparatus according to one embodiment of the present invention.

Claims (1)

(57) [Claims] A light source and a light receiving element for detecting a spray amount of a sample solution by directly facing the inside of a glass pipe from a sample atomizer to a sample atomization or excitation unit are arranged. An atomized sample introduction device for spectroscopic analysis, wherein an air curtain is formed by a carrier gas for transporting sample mist droplets in front of a light receiving element.