JPH11223619A - Hydrogen flame ionization detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent gathering of drain water in a combustion chamber after extinuishing a hydrogen flame, and to prevent reduction in detecting sensitivity by waterdrops and the occurrence of a drift and insulation failure in the combustion chamber by downward opening an exhaust port of a chimney forming the combustion chamber on the inside, and discharging the drain water from the exhaust port. SOLUTION: The top part 2 of a chimney 1 formed in a horizontal cylindrical shape is blocked up, and a hydrogen flame 5 generated on the tip of a nozzle 4 arranged in a combustion chamber 3 is ionized to be detected as an ion current by a lead 6 arranged on a side wall of the chimney 1. A downward exhaust port 7 is opened in the lower part of the side wall. Thus, since the exhaust port 7 is opened downward, drain water can be discharged outside from the exhaust port 7. Therefore, gathering of the drain water on the inside after extinuishing a hydrogen flame can be prevented to prevent reduction in detecting sensitivity by a waterdrop and the occurrence of insulation failure in the combustion chamber 3. Particularly, the effect is increased further by arranging the part of the lead 6 in the upper part of the chimney 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame ionization detector used for measuring, for example, the concentration of all hydrocarbons contained in exhaust gas from automobiles.

[0002]

2. Description of the Related Art A flame ionization detector is sensitive to organic compounds, provides a signal substantially proportional to the number of carbon atoms contained therein, and has relatively excellent stability. It is widely used as a detector of a gas analyzer.

In such a hydrogen flame ionization detector, conventionally, as shown in FIG. 2, for example, a chimney d having a combustion chamber c having a nozzle b for generating a hydrogen flame a is provided vertically upward. An exhaust port e is opened at the top, and an ion current is detected by a lead f provided on the side wall.

[0004]

However, in the above-described conventional flame ionization detector, water vapor generated when hydrogen is burned is condensed around the exhaust port e after the flame is extinguished to form water droplets. The next time a hydrogen flame is generated due to falling to the lower part and adhering to the nozzle b, the detection sensitivity may be affected by the water droplets next time, and the insulation failure in the combustion chamber c may occur. Was.

[0005] In addition, a temperature control wind or the like may be blown into the combustion chamber c from an exhaust port e opened at the top of the chimney d, thereby causing fluctuations in the hydrogen flame a and causing a non-standard line of the detection signal. In some cases, the stability was affected. In addition, insufficiency of insulation and fluctuation of hydrogen flame due to generation of water vapor sometimes cannot be ignored by a high-sensitivity meter.

The present invention has been made in view of such circumstances,
It is an object of the present invention to provide a flame ionization detector with reduced influence of water droplets and disturbance.

[0007]

According to the present invention, means for solving the above-mentioned problems are constituted as follows. That is, the first aspect of the present invention is characterized in that the exhaust port of the chimney in which the combustion chamber is formed is opened downward, and drain water is discharged from the exhaust port.

Since the exhaust port of the chimney is opened downward, drain water can be discharged from the exhaust port to the outside, and the drain water is prevented from accumulating in the combustion chamber after extinguishing the hydrogen flame.

According to a second aspect of the present invention, the chimney according to the first aspect of the invention is arranged laterally.

In particular, by arranging the chimney horizontally, drain water can be easily discharged to the outside from an exhaust port opened downward.

According to a third aspect of the present invention, the top of the chimney in the first or second aspect of the invention is closed.

By closing the top of the chimney, it is possible to make it less susceptible to disturbances caused by blowing in a temperature control wind.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a flame ionization detector according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view of a flame ionization detector. Reference numeral 1 denotes a chimney formed in a laterally cylindrical shape, the top 2 of which is closed, and a nozzle 4 is provided in a combustion chamber 3 formed therein. The hydrogen flame 5 generated at the tip of the nozzle 4 is ionized and detected as an ion current by a lead 6 provided on the side wall of the chimney 1. A downward exhaust port 7 is provided at a lower portion of the side wall. Has been established.

With the above configuration, first, the exhaust port 7
, The drain water can be discharged from the exhaust port 7 to the outside. Therefore, drain water is prevented from accumulating in the combustion chamber 3 after the extinguishing of the hydrogen flame, and a drop in detection sensitivity due to water droplets and occurrence of insulation failure in the combustion chamber 3 are prevented. In particular, when the lead 6 is provided above the chimney, the effect is further increased.

Further, since the chimney 1 is turned sideways and its top 2 is closed, the chimney 1 is less susceptible to disturbances such as the blowing of temperature-controlled air in the room, and the influence of the background is reduced. Thus, the baseline can be stabilized.

[0016]

As described above, according to the hydrogen flame ionization detector of the present invention, since the exhaust port of the chimney is opened downward, the accumulation of drain water in the combustion chamber after extinguishing the hydrogen flame is prevented. A drop in detection sensitivity due to water droplets and the like, and occurrence of flicker and insulation failure in the combustion chamber are prevented.

Further, by disposing the chimney horizontally, it becomes easier to drain the drain water from the exhaust port opened downward.

By closing the top of the chimney, it is possible to make it less susceptible to disturbances caused by blowing in a temperature-controlled wind or the like.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a hydrogen flame ionization detector of the present invention.

FIG. 2 is a perspective view showing an example of a conventional flame ionization detector.

[Explanation of symbols]

 1. Chimney, 2 top, 3 combustion chamber, 7 exhaust port.

Claims (3)

[Claims] 1. A flame flame ionization detector characterized in that an exhaust port of a chimney in which a combustion chamber is formed is opened downward, and drain water is discharged from the exhaust port. 2. The flame ionization detector according to claim 1, wherein the chimney is arranged horizontally. 3. The flame ionization detector according to claim 1, wherein a top portion of the chimney is closed.