JP3224551U - Infrared gas analyzer - Google Patents

Abstract

An infrared gas analyzer capable of shortening a warm-up time after power-on is provided. A light source, a cell on which infrared light is incident, a detector for receiving infrared light, a sector for switching the amount of infrared light incident on the cell, and a sector. A motor 16 for rotating the motor, a holding unit 17 for holding the motor 16, and a cooling fan 18 are provided. The light source 11 emits infrared light. The motor 16 rotates the sector 15. The holding unit 17 holds the light source 11 and the motor 16 side by side with a space 19 therebetween. The cooling fan 18 rotates about the rotation shaft 181. The cooling fan 18 is arranged such that the rotating shaft 181 extends in a direction intersecting with the direction D in which the light sources 11 and the motors 16 are arranged, and the space 19 is offset from the axis L of the rotating shaft 181. . [Selection] Fig. 2A

Description

  The present invention relates to an infrared gas analyzer.

  An infrared gas analyzer may be used as a device for detecting a measurement target component contained in a sample gas (for example, see Patent Document 1 below). The infrared gas analyzer is provided with a cell, and a sample gas supplied into the cell is irradiated with infrared light from a light source. The infrared light that has passed through the cell is received by the detector, and the concentration of the measurement target component in the sample gas is measured based on the amount of received light.

  The amount of infrared light incident on the cell from the light source is switched by a sector arranged between the light source and the cell. The sector is, for example, a plate-like member having an opening formed therein. The sector is rotatable by driving a motor, and is rotatable between a position where the opening faces the light source and a position where the opening does not face the light source. When the opening faces the light source, infrared light enters the cell from the light source, and when the opening does not face the light source, infrared light enters the cell from the light source.

JP-A-6-201583

  Both the light source and the motor become heat sources by generating heat during operation. Heat generated from these heat sources is transmitted to the cell and the detector. When the temperature of the cell and the detector is unstable, an error occurs in the measured value. Therefore, after turning on the power of the infrared gas analyzer, a warm-up operation is required until the temperature of the cell and the detector is stabilized. From the viewpoint of improving work efficiency, it is preferable that the warm-up time after turning on the power is short. In particular, this need is high in a portable infrared gas analyzer whose location is changed.

  The present invention has been made in view of the above circumstances, and has as its object to provide an infrared gas analyzer capable of shortening a warm-up time after power is turned on.

  A first aspect of the present invention is an infrared gas analyzer including a light source, a cell, a detector, a sector, a motor, a holding unit, and a cooling fan. The light source emits infrared light. Infrared light from the light source enters the cell. The detector receives infrared light that has passed through the cell. The sector switches the amount of infrared light that enters the cell from the light source. The motor rotates the sector. The holding unit holds the light source and the motor side by side with a space therebetween. The cooling fan rotates about a rotation axis. The cooling fan is arranged such that the rotation axis extends in a direction intersecting a direction in which the light source and the motor are arranged, and the space is offset from an axis of the rotation axis.

  According to the first aspect of the present invention, by cooling the light source and the motor using the cooling fan, heat transferred from the light source and the motor to the cell and the detector is reduced, and the temperature of the cell and the detector is reduced in a short time. Since it can be stabilized, the warm-up time after turning on the power can be reduced. Since the position of the space between the light source and the motor is shifted with respect to the axis of the rotation axis of the cooling fan, wind from the cooling fan easily flows into the space, and the light source and the motor are efficiently cooled. Can be.

It is the perspective view which showed an example of the external appearance structure of an infrared gas analyzer. It is the schematic side view which showed 1st Embodiment of the measurement part. It is a schematic plan view of the measurement part of FIG. 2A. It is the schematic side view which showed 2nd Embodiment of the measurement part. It is a schematic plan view of the measurement part of FIG. 3A.

1. FIG. 1 is a perspective view showing an example of an external configuration of the infrared gas analyzer 1. As shown in FIG. The infrared gas analyzer 1 is a device for measuring the concentration of a measurement target component such as carbon monoxide, carbon dioxide, or methane contained in a sample gas.

  The infrared gas analyzer 1 is a portable and compact device, and a measurement unit for measuring the concentration of a measurement target component is housed in a housing 2. In the housing 2, not only the measurement unit but also various electric components such as a pump and a cooler (both not shown) are housed. The user carries the housing 2 and installs it at a desired place, and supplies power to the infrared gas analyzer 1 from an AC power supply via an electric outlet (not shown), so that the infrared gas analyzer 1 can be easily operated. Can be used.

  The housing 2 includes an operation unit 3 and a display unit 4. The operation unit 3 includes, for example, a plurality of buttons. The user can operate the operation unit 3 to instruct the operation of the infrared gas analyzer 1 and perform various setting operations. The display unit 4 includes, for example, a liquid crystal display. The display unit 4 displays the settings of the infrared gas analyzer 1 and the measurement results.

  On the side surface of the housing 2, an air inlet 5 for sucking air into the housing 2 is formed. An intake fan 6 is provided at a position facing the intake port 5 in the housing 2. By driving the intake fan 6, air outside the housing 2 can be guided into the housing 2 from the air inlet 5 and can be smoothly sucked.

2. First Embodiment of Measurement Unit FIG. 2A is a schematic side view showing a first embodiment of the measurement unit 10. FIG. 2B is a schematic plan view of the measurement unit 10 of FIG. 2A. The measurement unit 10 includes a light source 11, a cell 12, a condenser 13, a detector 14, a sector 15, a motor 16, a holding unit 17, a cooling fan 18, and the like. These parts are integrally formed by being connected to each other.

  In this embodiment, two light sources 11, two cells 12, two light collectors 13, and two detectors 14 are provided. The two cells 12 have lengths corresponding to the concentrations of the components to be measured, and have different lengths. Specifically, the cell 12 is formed longer as the concentration of the measurement target component is lower, and the cell 12 is formed shorter as the concentration of the measurement target component is higher.

  Each light source 11 is an infrared light source that emits infrared light. The cell 12, the light collector 13, and the detector 14 are arranged in this order on the optical axis of the infrared light emitted from the light source 11. Each cell 12 is separated into a sample cell 121 and a comparison cell 122. Each of the sample cell 121 and the comparison cell 122 extends in parallel with the optical axis of the infrared light emitted from the light source 11. A sample gas containing a component to be measured is introduced into the sample cell 121. On the other hand, a gas serving as a reference when measuring the concentration of the measurement target component in the sample gas is sealed in the comparison cell 122.

  Infrared light from the light source 11 is incident on the sample cell 121 and the comparison cell 122, respectively. A part of the infrared light incident on each of the sample cell 121 and the comparison cell 122 is absorbed by the component to be measured, and only the light that has passed through the cells 121 and 122 is condensed by the light condensing device 13 and the detector The light is received by 14. Since the infrared light is absorbed in proportion to the concentration of the measurement target component, the concentration of the measurement target component in the gas can be measured based on the amount of infrared light received by the detector 14.

  The infrared light incident on the sample cell 121 and the comparison cell 122 can be restricted by the sector 15. The sector 15 is a plate-shaped member extending in a direction intersecting (for example, orthogonally) to the optical axis of the infrared light, and has one or a plurality of openings 151 formed therein. The motor 16 has a drive shaft 161 connected to the sector 15. The drive shaft 161 extends parallel to the optical axis of the infrared light. The motor 16 can rotate the sector by rotating the drive shaft 161.

  In this example, at least two openings 151a and 151b are formed in the sector 15. One opening 151 a can pass between the sample cell 121 and the light source 11. When the sector 15 is rotated by driving the motor 16, the position of the opening 151a is switched between a position facing the sample cell 121 and a position not facing the sample cell 121. When the opening 151a faces the sample cell 121, infrared light from the light source 11 enters the sample cell 121. On the other hand, when the opening 151 a does not face the sample cell 121, infrared light from the light source 11 does not enter the sample cell 121. That is, the amount of infrared light incident from the light source 11 into the sample cell 121 is switched by the sector 15.

  The other opening 151 b can pass between the comparison cell 122 and the light source 11. When the sector 15 is rotated by the drive of the motor 16, the opening 151b switches between a position facing the comparison cell 122 and a position not facing the comparison cell 122. When the opening 151b faces the comparison cell 122, infrared light from the light source 11 enters the comparison cell 122. On the other hand, when the opening 151b does not face the comparison cell 122, infrared light from the light source 11 does not enter the comparison cell 122. That is, the amount of infrared light incident from the light source 11 into the comparison cell 122 is switched by the sector 15.

  When the motor 16 is driven, infrared light from the light source 11 alternately enters the sample cell 121 and the comparison cell 122. As a result, the light that has passed through the sample cell 121 and the light that has passed through the comparison cell 122 are individually detected by the detector 14 by time division.

  The holding unit 17 holds the light source 11 and the motor 16. In this example, the holding portion 17 is a hollow member, and houses the sector 15 therein. In addition, the holding unit 17 integrally holds not only the light source 11 and the motor 16 but also the cell 12, the condenser 13, the detector 14, and the cooling fan 18. However, a holding unit for holding the light source 11 and the motor 16 may be provided as another member.

  The light source 11 and the motor 16 held by the holder 17 are arranged side by side with a space 19 therebetween. In the present embodiment, two light sources 11 (a first light source 111 and a second light source 112) are provided, and the first light source 111 is disposed at a distance from the motor 16 with a first space 191 therebetween. Reference numeral 112 is arranged between the motor 112 and the motor 16 with a second space 192 therebetween. The first space 191 and the second space 192 have the same area, but are not limited thereto.

  The cooling fan 18 is supported at a fixed position separated from the light source 11 and the motor 16 by a support member 183 fixed to the holding unit 17 (the support member 183 is omitted in FIG. 2B). However, the cooling fan 18 may be supported separately from the holding unit 17.

  The cooling fan 18 includes a rotating shaft 181 and a plurality of blades 182. The rotating shaft 181 extends in a direction parallel to the optical axis direction of the infrared light from the light source 11, and is rotated by a driving source different from the motor 16 (for example, another motor). The plurality of blades 182 are fixed so as to radially extend in the radial direction with respect to the rotation shaft 181. The cooling fan 18 generates wind in a direction parallel to the direction in which the rotating shaft 181 extends by being rotated about the rotating shaft 181.

  The rotating shaft 181 extends in a direction crossing the direction D in which the light source 11 and the motor 16 are arranged, and in a direction parallel to the optical axis direction of the infrared light. A drive shaft 161 of the motor 16 extends on the axis L of the rotation shaft 181. The “intersecting direction” may be a direction intersecting at 90 ° (orthogonal direction) or a direction inclined with respect to the orthogonal direction (for example, a direction intersecting at 80 ° to 100 °).

  The first light source 111 and the second light source 112 are arranged with the motor 16 interposed therebetween. Thus, a first space 191 and a second space 192 are formed on both sides of the motor 16. The space 19 (the first space 191 and the second space 192) is not located on the axis L of the rotating shaft 181 and the rotating shaft 181 is located in a region between the first space 191 and the second space 192. Cooling fan 18 is arranged as described above. That is, the first space 191 and the second space 192 are offset from the axis L of the rotation shaft 181. Thus, the blades 182 of the cooling fan 18 can be opposed to the first space 191 and the second space 192. Wind generated from each blade 182 in a direction parallel to the rotation axis 181 is blown to the first space 191 and the second space 192.

  A temperature sensor 20 for measuring the temperature of the measurement unit 10 is provided in the housing 2. For example, only one temperature sensor 20 is provided. In this example, a temperature sensor 20 is attached to a metal block constituting one of the light collectors 13. However, the installation position of the temperature sensor 20 is arbitrary, and the temperature sensor 20 may be attached to another member constituting the measurement unit 10.

  When the power of the infrared gas analyzer 1 is turned on, the operations of the light source 11, the motor 16, the cooling fan 18, and the intake fan 6 are started. The light source 11 and the motor 16 both generate heat as they operate, thereby becoming heat sources. Since the heat generated from these heat sources is transmitted to the cell 12 and the detector 14, the warm-up operation is performed until the temperatures of the cell 12 and the detector 14 are stabilized. After the warm-up operation is completed, the control unit (not shown) provided in the infrared gas analyzer 1 performs the analysis while correcting the temperature of the optical system based on the temperature detected by the temperature sensor 20. .

3. Second Embodiment of Measurement Unit FIG. 3A is a schematic side view showing a second embodiment of the measurement unit 10. FIG. 3B is a schematic plan view of the measurement unit 10 of FIG. 3A. In the second embodiment, since only the installation mode of the cooling fan 18 is different from the first embodiment, the same components as those in the first embodiment are denoted by the same reference numerals in the drawings, and detailed description is omitted.

  The cooling fan 18 is supported by the holding unit 17 at a fixed position separated from the light source 11 and the motor 16. However, the cooling fan 18 may be supported separately from the holding unit 17. The rotation axis 181 of the cooling fan 18 extends in a direction orthogonal to the optical axis direction of the infrared light from the light source 11.

  The rotation shaft 181 extends in a direction orthogonal to the direction D in which the light source 11 and the motor 16 are arranged and in a direction orthogonal to the optical axis direction of the infrared light. The “orthogonal direction” is a concept including not only 90 ° but also a direction slightly inclined with respect to 90 °, and may include, for example, a range of 80 ° to 100 °.

  The space 19 (the first space 191 and the second space 192) is not located on the axis L of the rotating shaft 181 and the rotating shaft 181 is located in a region between the first space 191 and the second space 192. Cooling fan 18 is arranged as described above. Thus, the blades 182 of the cooling fan 18 can be opposed to the first space 191 and the second space 192. Wind generated from each blade 182 in a direction parallel to the rotation axis 181 is blown to the first space 191 and the second space 192.

4. Modified Example Each light source 11 is not limited to the configuration in which the motor 16 is interposed therebetween, but may be arranged in another position on the circumference around the motor 16. In this case, the distance between each light source 11 and the motor 16 may be the same or substantially the same.

  In the above embodiment, the configuration in which only one cooling fan 18 is provided has been described. However, the configuration is not limited to such a configuration, and a configuration in which a plurality of cooling fans 18 are provided may be used. Further, the light source 11, the cell 12, the light collector 13, and the detector 14 are not limited to the configuration provided with two each, and may be the configuration provided one by one, or three or more each may be provided. A configuration may be adopted. The intake fan 6 can be omitted. Further, an exhaust fan may be provided instead of the intake fan 6, and the air in the housing 2 may be exhausted from the exhaust port by the exhaust fan.

  The cell 12 is not limited to the configuration including the sample cell 121 and the comparison cell 122, and may be a configuration including only the sample cell 121. In this case, the sector 15 may have a configuration in which only one opening 151 is formed. Further, the light collector 13 may be configured to collect only the light that has passed through the sample cell 121 on the detector 14.

5. Aspects It will be appreciated by those skilled in the art that the exemplary embodiments described above are specific examples of the following aspects.

(Claim 1) An infrared gas analyzer according to one aspect is
A light source for irradiating infrared light,
A cell on which infrared light from the light source is incident,
A detector that receives infrared light that has passed through the cell,
A sector for switching the amount of infrared light incident on the cell from the light source,
A motor for rotating the sector;
A holding unit that holds the light source and the motor side by side with a space therebetween,
With a cooling fan that rotates around the rotation axis,
The cooling fan may be arranged such that the rotation axis extends in a direction intersecting a direction in which the light source and the motor are arranged, and the space is offset from an axis of the rotation axis. .

  According to the infrared gas analyzer described in Item 1, by cooling the light source and the motor using the cooling fan, the heat transmitted from the light source and the motor to the cell and the detector is reduced, and the temperature of the cell and the detector is reduced. Since the stabilization can be performed in a short time, the warm-up time after turning on the power can be reduced. Since the position of the space between the light source and the motor is shifted with respect to the axis of the rotation axis of the cooling fan, wind from the cooling fan easily flows into the space, and the light source and the motor are efficiently cooled. Can be.

(Item 2) In the infrared gas analyzer according to Item 1,
The light source includes a first light source disposed with a first space between the motor and the second light source, and a second light source disposed with a second space between the first light source and the motor.
The cooling fan may be arranged so that the first space and the second space are not located on the axis of the rotation shaft.

  According to the infrared gas analyzer described in Item 2, wind from the cooling fan can be sent to the first space and the second space, and the light source and the motor can be efficiently cooled.

(Item 3) In the infrared gas analyzer according to item 2,
The first light source and the second light source are arranged with the motor interposed therebetween,
The cooling fan may be arranged so that the rotation axis is located in a region between the first space and the second space.

  According to the infrared gas analyzer described in Item 3, the air from the cooling fan can be efficiently sent to the first space and the second space, and the light source and the motor can be cooled more efficiently.

(Item 4) In the infrared gas analyzer according to any one of Items 1 to 3,
The cooling fan may be arranged so that the rotation axis extends in a direction parallel to an optical axis direction of the infrared light from the light source.

  According to the infrared gas analyzer described in Item 4, the air from the cooling fan is sent to the space between the light source and the motor along the direction parallel to the optical axis direction of the infrared light, and the light source and the motor Can be efficiently cooled.

(Item 5) In the infrared gas analyzer according to any one of Items 1 to 3,
The cooling fan may be arranged so that the rotation axis extends in a direction orthogonal to an optical axis direction of the infrared light from the light source.

  According to the infrared gas analyzer described in Item 5, the air from the cooling fan is sent to the space between the light source and the motor along the direction orthogonal to the optical axis direction of the infrared light, and the light source and the motor Can be efficiently cooled.

(Item 6) In the infrared gas analyzer according to any one of Items 1 to 5,
A housing that houses the light source, the cell, the detector, the sector, the motor, the holding unit, and the cooling fan;
The air conditioner may further include a fan that draws air into or exhausts from the housing.

  According to the infrared gas analyzer described in the above item 6, since the fan can be efficiently taken in or exhausted from the inside of the housing, the light source and the motor can be cooled more efficiently.

(Item 7) The infrared gas analyzer according to any one of Items 1 to 6 may be portable.

  According to the infrared gas analyzer described in Item 7, in the portable infrared gas analyzer, the light source and the motor can be efficiently cooled, and the warm-up time after turning on the power can be shortened.

DESCRIPTION OF SYMBOLS 1 Infrared gas analyzer 2 Case 5 Inlet 6 Inlet fan 10 Measuring unit 11 Light source 12 Cell 13 Condenser 14 Detector 15 Sector 16 Motor 17 Holding unit 18 Cooling fan 19 Space 20 Temperature sensor 111 First light source 112 Second Light source 181 Rotation axis 191 First space 192 Second space

Claims (7)

A light source for irradiating infrared light,
A cell on which infrared light from the light source is incident,
A detector that receives infrared light that has passed through the cell,
A sector for switching the amount of infrared light incident on the cell from the light source,
A motor for rotating the sector;
A holding unit that holds the light source and the motor side by side with a space therebetween,
With a cooling fan that rotates around the rotation axis,
The cooling fan is arranged such that the rotation axis extends in a direction intersecting a direction in which the light source and the motor are arranged, and the space is arranged so as to be offset from an axis of the rotation axis. Gas analyzer. The light source includes a first light source disposed with a first space between the motor and the second light source, and a second light source disposed with a second space between the first light source and the motor.
The infrared gas analyzer according to claim 1, wherein the cooling fan is arranged such that the first space and the second space are not located on an axis of the rotation shaft. The first light source and the second light source are arranged with the motor interposed therebetween,
The infrared gas analyzer according to claim 2, wherein the cooling fan is arranged such that the rotation axis is located in a region between the first space and the second space.   The infrared gas analysis according to any one of claims 1 to 3, wherein the cooling fan is arranged such that the rotation axis extends in a direction parallel to an optical axis direction of the infrared light from the light source. Total.   The infrared gas analysis according to any one of claims 1 to 3, wherein the cooling fan is arranged such that the rotation axis extends in a direction orthogonal to an optical axis direction of the infrared light from the light source. Total. A housing that houses the light source, the cell, the detector, the sector, the motor, the holding unit, and the cooling fan;
The infrared gas analyzer according to any one of claims 1 to 5, further comprising: a fan that intakes or exhausts air into the housing.   The infrared gas analyzer according to any one of claims 1 to 6, which is portable.

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