JPH0573564U - Infrared gas analyzer - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an infrared gas analyzer that is compact, low-cost, and has good indicating stability. [Structure] A cell 1 is formed by covering an upper part and a lower part of a cylindrical cell body 2 arranged in a standing manner with an upper bottom 4 and a lower bottom 6, respectively, and a light source 7 for irradiating infrared rays and its infrared rays. A pair of infrared sensors 8 and 9 for comparison and measurement that receive light
Are provided inside the upper bottom 4 or the lower bottom 6 so as to face each other, and a gas inlet 61 for introducing a sample gas into the cell 1 is provided in the lower portion of the cell 1. Gas outlets S for discharging the sample gas are provided in the upper portion of the cell 1, respectively.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an infrared gas analyzer which measures the concentration of a specific component by irradiating a sample gas with infrared rays.

[0002]

[Prior Art]

 The infrared gas analyzer irradiates the sample gas introduced into the cell with infrared rays and detects the amount of light with an infrared sensor for comparison and an infrared sensor for measurement, and based on the difference, the component gas is detected. The concentration of is detected.

In such an infrared gas analyzer, in general, a filament is often used as a light source for irradiating infrared rays. In that case, the filament is CO ₂ or H ₂ 0 in the atmosphere. It is necessary to prevent the influence of the above, that is, the influence of the atmosphere, and for that purpose, the filament was housed in a metal block, an optical crystal window was provided, and argon gas or the like was sealed inside.

[0004]

[Problems to be solved by the device]

 In the conventional infrared gas analyzer as described above, the structure itself for accommodating the filament is complicated and expensive, and also the cost of filling the argon gas under vacuum is also high, which is bulky in general. However, the cost was high and the cost was high.

In addition, the instruction floats over time due to the deterioration of the enclosed gas, that is, the decrease in the purity of the enclosed gas due to the gas released from the adhesive, filament, and other components used for attaching the optical crystal window. There were also some difficulties.

The present invention has been made in consideration of such circumstances, and an object of the present invention is to provide an infrared gas analyzer which is compact, low in cost, and has good pointing stability.

[0007]

[Means for Solving the Problems]

 The present invention has means for solving the above-mentioned problems as follows. That is, the cell is formed by covering the upper part and the lower part of a vertically arranged cylindrical cell body with the upper bottom and the lower bottom, respectively, and comparing the infrared light source with the infrared light source. And a pair of infrared sensors for measurement are provided inside the upper bottom or the lower bottom so as to face each other, and a gas inlet for introducing a sample gas into the cell is provided. The cell is characterized in that gas outlets for discharging sample gas are provided at the bottom of the cell and at the top of the cell, respectively.

[0008]

[Action]

 Infrared rays emitted from the light source to the sample gas introduced into the cell from the gas inlet are detected by a pair of infrared sensors for comparison and measurement, and the concentration of the component gas is quantified based on the detected difference. You can

[0009] The sample gas is introduced from a gas introduction port opened in the lower part of the standing cell and then heated up to expand its volume and rise until it is discharged from the upper gas discharge port to the outside. In the process, natural convection is induced and diffused quickly without any unevenness, so that not only a quick response can be obtained, but also the gas emitted from the light source does not stay in the cell and is discharged from the gas outlet together with the sample gas. As the light source is placed in the cell, the dead space exposed to the atmosphere is eliminated and the atmosphere is not affected by CO ₂ and H ₂ 0. It's gone.

Since the optical crystal window is unnecessary by housing the light source in the cell, the dead space is eliminated as described above, the structure is simple and compact, and the cost can be reduced. it can.

[0011]

【Example】

 Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view showing an embodiment of the infrared gas analyzer of the present invention. Reference numeral 1 is a vertically arranged cell, which is formed on the inner and outer surfaces of a cylindrical body obtained by molding a synthetic resin material or the like. A chrome-plated cell body 2 and an upper bottom 4 made of an aluminum alloy material formed by forming a circular arc-shaped gap S, which serves as a gas outlet, at the upper part of the cell body 2 and fastening the bolts 3 ... And a lower bottom 6 made of an aluminum alloy material, which is integrated by fastening bolts 5, ..., At the bottom of the cell body 2, and is formed compact and robust.

The upper base 4 is formed in a substantially conical shape, and a filament 7 serving as a light source is attached to the inner side of the central portion of the upper base 4 so as to face downward. Are formed so as to cover the gap S with the cell body 2, and bolt holes 42 for inserting the bolts 3 are formed at three locations. The cell body 2 corresponding to each bolt hole 42 is formed in the cell body 2. A boss portion 21 for forming the gap S is formed in a protruding manner, and a screw groove into which the bolt 3 for attaching the upper bottom 4 is screwed is formed in a protruding manner in the boss portion 21.

With this structure, each boss portion 21 of the cell body 2 is connected to the bolt hole 42 of the upper bottom 4 and the bolt 3 is fastened to the boss portion 21 of the cell body 2. The upper space 4 can be stably fixed by forming the arcuate gap S. Further, by appropriately interposing a thin plate material such as a shim or a washer between the boss portion 21 and the upper bottom 4, it is possible to set and change the interval of the gap S very easily.

On the other hand, a gas introduction port 61 for introducing a sample gas is formed in the center of the lower bottom 6 so as to vertically penetrate therethrough, and a pair of holes 62, 62 formed on both sides of the gas introduction port 61. An infrared sensor 8 for comparison and an infrared sensor 9 for measurement are housed, and optical filters 10, 11 are provided on the upper surface of each infrared sensor 8, 9 via a packing material (not shown) such as silicon rubber. Is attached.

A printed circuit board 15 is integrated with bolts 16 at the lower part of the lower bottom 6 through an interposer plate 14 having through holes 12 and 13 corresponding to the infrared sensors 8 and 9, respectively. The heat insulating material 17 and the mounting frame 18 are integrated under the lint substrate 15, the nozzle 19 is connected to the gas inlet 61, and the heat insulating material 20 is attached to the inner surface. For measurement of CO ₂ in the atmosphere, the gas inlet 61 may be formed in the same configuration as the gap S of the gas outlet as shown in FIG. 2, for example.

In the infrared gas analyzer configured as described above, the sample gas introduced into the cell 1 from the gas inlet 61, such as CO _2, is heated by the heat generated from the filament 7 and its volume is expanded and raised. Since natural convection is induced and evenly diffused in the process of being discharged to the outside from the arcuate gap S serving as the gas discharge port in the upper part, a quick response can be obtained. By adjusting the gap S, the effect of preventing dust and dust from entering and the effect of wind from the surroundings can be obtained in combination with the effect of shielding the circumferential flange 41. The sample gas can be introduced by natural convection without pressurization, but may be introduced by pressurization via a pump.

Since the filament 7 is not provided with an optical window, the gas released from the filament 7 does not stay in the cell 1 and is discharged together with the sample gas from the gap S to the outside. The problem that the detected value floats is solved.

Further, since the filament 7 is provided in the cell 1, there is no dead space exposed to the atmosphere as in the conventional case, and the so-called atmosphere due to CO ₂ , H ₂ 0, etc. is not affected and reliability is improved. Can be improved.

Further, as described above, the optical crystal window is not required by accommodating the filament 7 in the cell 1, so that the dead space is eliminated and the structure is simple and compact, and the cost is reduced. be able to.

FIG. 3 shows another embodiment in which harmful gases such as CO, NO _x , SO _x , and HC can be detected, and the sample gas containing these is discharged to a specific location or post-processed. Therefore, the nozzle-shaped gas outlet S is provided in the upper part of the cell body 2, while the nozzle-shaped gas inlet 61 is provided in the lower part of the cell body 2 to introduce the sample gas through the hose. It is possible to discharge. In this case, it is desirable to direct each nozzle in the direction along the inner peripheral surface of the cell body 2 so that the sample gas is circulated along the inner peripheral surface.

Although illustration is omitted, in the inverted type in which the filament is arranged on the lower bottom and both infrared sensors are arranged on the upper bottom, the temperature rising effect of the sample gas becomes better, so that the responsiveness is higher. It has been confirmed that it will be further improved.

[0022]

[Effect of the device]

 As described above, according to the infrared gas analyzer of the present invention, since the light source is provided inside the cell, the optical crystal window is not required, and the dead space exposed to the atmosphere as in the past is eliminated, and the configuration is It is simple and compact, and the cost can be reduced.

Since the dead space exposed to the atmosphere is eliminated, the atmosphere is not affected by CO ₂ and H ₂ 0 in the atmosphere, and the reliability is improved.

Further, since the optical crystal window is not required and the enclosed gas is not used, the gas emitted from the light source component does not stay in the cell and is discharged together with the sample gas from the gas outlet provided in the upper part of the cell to the outside. Since the gas is discharged, it is possible to solve the problem that the enclosed gas is deteriorated and causes the instruction to float over time as in the conventional case.

Further, since the sample gas is naturally convected during the process of being introduced from the gas introduction port opened in the lower portion of the standing cell and discharged from the upper gas outlet port, it is diffused evenly and promptly. You can also get a quick response.

It should be noted that the present invention does not limit the cell body and the upper and lower bottoms to those of the embodiment. Therefore, the structures and materials of these and the structure for integrating them are not limited to the usage conditions, application targets, etc. It can be appropriately selected or set / changed depending on the type.For example, a metal material may be used for the cell body, and the boss portion for forming the gap may be formed on the upper bottom. Instead of the parts, an interposing member may be interposed between the cell body and the upper bottom. Further, the gas inlet and the gas outlet are not limited to those in the embodiment, and for example, a long hole in the circumferential direction may be formed in the lower portion or the upper portion of the cell body to use these as the gas inlet and the gas outlet. Needless to say.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of an infrared gas analyzer of the present invention.

FIG. 2 is a partially enlarged view showing another embodiment of the gas introduction port.

FIG. 3 is a vertical sectional view of an infrared gas analyzer according to another embodiment.

[Explanation of symbols]

1 ... Cell, 2 ... Cell body, 4 ... Top bottom, 6 ... Bottom bottom, 7 ... Light source, 8 ... Infrared sensor for comparison, 9 ... Infrared sensor for measurement, 61 ... Gas inlet, S ... Gas Vent.

Claims (1)

[Scope of utility model registration request] 1. A light source for irradiating infrared rays, and a light source for receiving the infrared rays, wherein cells are formed by covering an upper portion and a lower portion of a cylindrical cell body vertically arranged by an upper bottom and a lower bottom, respectively. A pair of infrared sensors for comparison and measurement, as opposed to each other, each provided inside the upper bottom or the lower bottom, a gas inlet for introducing a sample gas into the cell An infrared gas analyzer characterized in that gas outlets for discharging sample gas are provided in the lower part of the cell and in the upper part of the cell, respectively.