JP6916667B2 - Probe device and exhaust gas analyzer - Google Patents

Description

The present invention provides, for example, a probe device attached to the exhaust pipe of a combustion device such as an engine, a boiler, a waste combustion furnace, an industrial furnace, and an exhaust gas flowing through a flue in the exhaust pipe based on the output from the probe device. It relates to an exhaust gas analyzer that analyzes a predetermined component contained therein.

Conventionally, as an exhaust gas analyzer that detects and analyzes components contained in exhaust gas in a flue, as shown in Patent Document 1, a probe device is directly inserted into the flue and attached, and the exhaust gas is sampled by the probe device. At the same time, there is one that analyzes a predetermined component such as nitrogen oxide in the exhaust gas.

This probe device includes a sensor holder 2A provided so as to penetrate the inside and outside of the flue as shown in FIG. 5, and a gas sensor 1A held in the sensor holder 2A. Exhaust gas is introduced from the flue to the tip of the sensor holder 2A, and an exhaust gas introduction space L1 to be introduced into the sensor portion 11A of the gas sensor 1A is formed.

The sensor holder 2A includes an inner tube 21A provided so as to surround the proximal end side of the gas sensor 1A, and an outer tube 23A provided concentrically on the outside of the inner tube 21A. Cooling air is allowed to flow from the inside of the inner pipe 21A to the space between the outer surface of the inner pipe 21A and the inner side surface of the outer pipe 23A, and the gas sensor 1A is generated by the heat of the exhaust gas flowing through the flue. It is configured to prevent it from breaking down.

Further, as shown in FIG. 6 which is a cross-sectional view taken along the line BB of FIGS. 5 and 5, two thin tubes P1 are formed in the space where the cooling air flows between the inner tube 21A and the outer tube 23A. P2 is provided, and each communicates with the exhaust gas introduction space L1. More specifically, a calibration gas flow path L2 for introducing the calibration gas into the exhaust gas introduction space L1 is formed in one of the thin tubes P1, and a purge gas is introduced into the exhaust gas introduction space L1 in the other thin tube P2. The purge gas flow path L4 is formed.

By the way, since the pressure of the exhaust gas in the flue fluctuates due to a change in the output of an internal combustion engine or the like, the output from the gas sensor may change due to the influence of the pressure fluctuation.

Further, since the calibration gas flow path and the purge gas flow path communicate with the exhaust gas introduction space, a part of the high temperature exhaust gas introduced from the flue may flow during normal measurement. Further, since the calibration gas flow path and the periphery of the purge gas flow path are filled with cooling air, the moisture in the exhaust gas is cooled and water droplets are generated. Therefore, sulfides and nitrides in the exhaust gas dissolve in water droplets to generate sulfuric acid and nitric acid, which invade the thin tubes forming the calibration gas flow path and purge gas flow path, shortening the life of the probe device. There is a possibility that it will end up.

Japanese Unexamined Patent Publication No. 2010-276550

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a probe device capable of realizing accurate measurement even if pressure fluctuation occurs in the exhaust gas flowing in the flue, and an exhaust gas analyzer. And.

Further, the present invention prevents the moisture in the exhaust gas flowing through the gas flow path communicating with the gas sensor, such as the calibration gas flow path, from liquefying, and prevents the piping forming the calibration gas flow path from being invaded by acid. An object of the present invention is to provide a probe device having a long life.

That is, the probe device according to the present invention is a probe device that samples exhaust gas flowing through the flue, and is provided so as to penetrate the inside and outside of the flue and a gas sensor including a sensor unit that comes into contact with the exhaust gas. In a sensor holder holding the gas sensor, a gas flow passage from the base end portion of the sensor holder formed on the sensor holder and arranged outside the flue to the sensor portion, or outside the flue. It is characterized by including a pressure sensor for measuring the pressure of the flow path communicating with the gas flow passage, and a correction processing unit for correcting the output of the gas sensor based on the output of the pressure sensor.

In such a case, even if the pressure of the exhaust gas flowing through the flue fluctuates, the output of the gas sensor is corrected by the correction processing unit according to the fluctuating pressure, so that the influence of the pressure fluctuation is eliminated. The measured value can be obtained.

Therefore, for example, stable analysis of exhaust gas can be realized regardless of the operating state of the internal combustion engine which is the source of exhaust gas. In addition, since the influence of pressure fluctuation can be eliminated from the gas sensor, it is not necessary to perform calibration operation in an internal combustion engine, which is a source of exhaust gas, for example, and perform calibration while maintaining a predetermined pressure. , It becomes easier to obtain more accurate measured values.

Further, since the pressure sensor measures the pressure of the exhaust gas passing through or after passing through the gas flow passage, the exhaust gas having a temperature lower than that in the flue can be brought into contact with the pressure sensor. .. Therefore, it is possible to prevent the pressure sensor from failing.

As a specific configuration example of the gas flow passage, the gas flow passage constitutes at least one of a calibration gas flow path and a purge gas flow path.

For example, a part of high-temperature exhaust gas also circulates in the gas flow passage during normal measurement other than the original purpose of use. Therefore, it is necessary to protect the main body of the gas sensor held in the sensor holder, which includes an electronic circuit or the like that is sensitive to high temperatures, from heat from the gas flow passage. Conventionally, the main body of the gas sensor has been arranged in the cooling space in which the cooling medium is introduced in the sensor holder.

By the way, when the gas flow passage is close to the cooling space, the water in the exhaust gas flowing through the gas flow passage is cooled and condensed, and the nitrogen oxides and sulfides in the exhaust gas are dissolved and the acidic liquid is dissolved. This may corrode the metal pipes that form the gas flow path. In order to prevent the condensation of water in the gas flow passage and solve the above-mentioned problems, the gas sensor further includes a main body portion held in the sensor holder outside the exhaust gas introduction space. Yes, it is formed in the sensor holder, further includes a cooling space in which the main body of the gas sensor is accommodated and a cooling medium is introduced, and a heat insulating layer is formed between the cooling space and the gas flow passage. Just do it.

In order to heat the exhaust gas flowing through the gas flow passage by the heat of the exhaust gas flowing through the flue so that the moisture in the exhaust gas is less likely to condense, at least a part of the gas flow passage is inside the flue. It suffices if it is formed in the tip of the sensor holder that protrudes toward.

The heat of the exhaust gas flowing through the flue warms the exhaust gas flowing through the gas flow passage to prevent the condensation of water, and the gas sensor flows through the exhaust gas flowing through the flue or the gas flow passage. In order to prevent the temperature from rising due to the exhaust gas, the sensor holder has a multi-tube structure including at least an inner tube and an outer tube, and the cooling space is formed inside the inner tube to form the inner tube and the inner tube. Any gas flow passage may be formed between the outer pipe and the inner surface of the outer pipe.

For example, by making it difficult for heat transfer to occur due to the air layer between the cooling space and the gas flow passage, it is difficult for the exhaust gas flowing through the gas flow passage to be cooled by the cooling medium, and moisture in the exhaust gas is condensed. To be able to prevent, the sensor holder further comprises a partition tube between the inner tube and the outer tube, between the outer surface of the inner tube and the inner surface of the partition tube. Anything may be used as long as the heat insulating layer is formed by the space.

The flow rate of the gas that can flow through the gas flow passage can be secured, and the heat of the exhaust gas flowing through the flue can be blocked by the gas flow passage over the entire circumference of the sensor holder, so that the gas sensor becomes hot. In order to make it difficult for the gas sensor to be formed, the gas flow passage may be formed so as to surround the outer surface of the inner pipe over the entire circumference when the cross section of the sensor holder is viewed.

When a filter is provided so as to prevent minute particles or the like contained in the exhaust gas flowing through the flue from coming into contact with the gas sensor and hindering the measurement, the filter collects a predetermined amount or more of particles. In order to automatically detect that it is difficult to continue the measurement, at least a part thereof is formed in the tip portion of the sensor holder protruding into the flue, and the sensor portion of the gas sensor is accommodated. In addition, the exhaust gas introduction space into which the exhaust gas is introduced from the flue, the filter that separates the flue and the exhaust gas introduction space, the measured pressure value indicated by the output of the pressure sensor, and the predetermined reference value are set. Anything may be provided as long as it is further provided with a clogging determination unit for determining the presence or absence of clogging of the filter based on the above.

If the exhaust gas analyzer includes the probe device according to the present invention and the main body of the analyzer that analyzes the exhaust gas flowing through the flue based on the output from the gas sensor, the influence of the pressure fluctuation of the exhaust gas flowing through the flue. It is possible to obtain the correct analysis result excluding. In addition, it is possible to obtain reliable measured values even in applications where maintenance and verification by specialists are difficult for a long period of time, such as analysis of exhaust gas emitted from an internal combustion engine of a ship.

Further, the correction method according to the present invention includes a gas sensor including a sensor unit that comes into contact with exhaust gas, and a sensor holder provided so as to penetrate the inside and outside of the flue and holding the gas sensor inside, and smoke. It is a method of correcting the output of the gas sensor using a probe device that samples the exhaust gas flowing through the road, and the exhaust gas is introduced from the base end portion of the sensor holder formed on the sensor holder and arranged outside the flue. A correction method for correcting the output of the gas sensor based on the output of a pressure sensor provided in the gas flow path leading to the space or the flow path communicating with the gas flow path outside the flue. A pressure sensor for measuring the pressure of the flow path communicating with the gas flow passage is provided outside the flue, and the output of the gas sensor is corrected based on the output of the pressure sensor.

If it is such a thing, even if the pressure fluctuation occurs in the exhaust gas flowing through the flue, the influence can be prevented from appearing in the output of the gas sensor. Further, since the gas sensor comes into contact with the exhaust gas flowing through the gas flow path or the flow path communicating with the gas flow path, the high temperature exhaust gas does not come into direct contact with the gas flow path, and the gas sensor is prevented from being damaged due to continuous exposure to the high temperature environment. Can be done.

According to the probe device according to the present invention, even if a pressure fluctuation occurs in the exhaust gas flowing through the flue, the gas sensor can be used based on the measured value of the pressure sensor provided in the gas flow path or the flow path communicating with the gas flow path. Since the output is corrected, a predetermined measurement accuracy can always be maintained. Further, since the pressure sensor is not directly provided in the flue, failure is unlikely to occur due to high temperature exhaust gas, and the output of the gas sensor can be corrected by a reliable pressure value for a long period of time.

The schematic diagram which shows the probe device which concerns on one Embodiment of this invention, and the exhaust gas analyzer. The schematic vertical sectional view which shows the detail of the structure in the sensor holder in the same embodiment. The schematic cross-sectional view which shows the detail of the structure in the sensor holder in the same embodiment. The functional block diagram of the probe device in the same embodiment. Schematic vertical cross-sectional view showing the configuration of a conventional probe device. Schematic cross-sectional view showing the configuration of a conventional probe device.

The probe device 100 according to the embodiment of the present invention and the exhaust gas analyzer 200 provided with the probe device 100 will be described with reference to each figure.

The probe device 100 and the exhaust gas analyzer 200 shown in FIG. 1 are included in the exhaust gas flowing through the flue LE in the exhaust pipe EP connected to an internal combustion engine such as a boiler, a gas engine, a marine engine, or an external combustion engine. The predetermined components (for example, NO _X , SO _X , CO ₂ , CO, etc.) and the like are analyzed. The analysis result (for example, the concentration of a predetermined component) obtained by the exhaust gas analyzer 200 is used for controlling denitration or desulfurization.

Specifically, as shown in FIG. 1, the exhaust gas analyzer 200 includes a gas sensor 1 which is fixed to the exhaust pipe EP and whose tip is projected into the flue LE to detect a predetermined component. The probe device 100 is provided with an analyzer main body 101 that receives a detection signal from the probe device 100 and continuously and at high speed analyzes a predetermined component contained in the exhaust gas. The analyzer main body 101 includes an arithmetic processing device such as a computer and a display device, and the probe device 100 and the analyzer main body 101 are connected by a cable.

As shown in FIG. 1, the probe device 100 partially samples the exhaust gas flowing through the flue LE and detects a predetermined component contained in the sampled exhaust gas. As shown in FIG. 1, the probe device 100 includes a cylindrical sensor holder 2 provided so as to penetrate the cylindrical exhaust pipe EP from the side surface, and a gas sensor 1 held inside the sensor holder 2. And have. Further, in the sensor holder 2, the exhaust gas sampled from the flue LE into the gas sensor 1 is provided with an exhaust gas introduction space L1 and a calibration gas flow path L2 for supplying the calibration gas to the gas sensor 1. A cooling space L3 is formed in which a part of the gas sensor 1 is cooled by a cooling medium. Further, a pressure sensor 3 is provided in the flow path provided so as to communicate with the calibration gas flow path L2, and a transmission between the calibration gas flow path L2 and the cooling space L3 is provided. A heat insulating layer TB that blocks heat is provided.

Further, the probe device 100 includes a gas sensor 1 and a calculation processing unit COM in which a predetermined calculation process is performed based on the output of the pressure sensor 3. In the present embodiment, the function of the arithmetic processing unit COM is realized by using the arithmetic capacity of the analyzer main body 101, and for example, the arithmetic of the microcomputer provided in the gas sensor 1 or the pressure sensor 3 is performed. The function may be realized by the ability.

Next, details of each part of the probe device 100 will be described.

The gas sensor 1 has a substantially cylindrical shape as shown in FIG. 3 which is a cross-sectional view taken along the line AA of FIGS. 2 and 2, and the tip side is arranged in the exhaust gas introduction space L1 and the base end side is the cooling. It is arranged in the space L3. More specifically, the tip side of the gas sensor 1 is the sensor unit 11 that comes into contact with the exhaust gas, and the base end side is the main body unit 12 that houses an electric circuit or the like for signal processing the output of the sensor unit 11. be. In other words, the sensor unit 11 is a sensitive unit in which the tip end side of the gas sensor 1 comes into contact with the exhaust gas sampled in the sensor holder 2 and reacts with a predetermined component. When a predetermined component is detected, a detection signal is output from the main body 12 to the analyzer main body 101 via a cable.

As shown in FIG. 1, the sensor holder 2 is a substantially cylindrical member inserted in the radial direction of the exhaust pipe EP from a mounting flange provided on the side surface of the exhaust pipe EP forming the flue LE. In other words, the sensor holder 2 is provided so that its axial direction is perpendicular to the flow of exhaust gas. In the present embodiment, the tip of the sensor holder 2 is arranged near the center of the axis of the flue LE. In the following description, the tip end portion of the sensor holder 2 refers to a portion of the sensor holder 2 inserted into the flue LE, and the base end portion of the sensor holder 2 refers to the flue LE. Refers to the part located on the outside.

As shown in FIG. 1, the sensor holder 2 has the exhaust gas introduction space L1 formed in the tip portion arranged in the flue LE with reference to the exhaust pipe EP forming the flue LE. In the present embodiment, all of the exhaust gas introduction space L1 is formed in the tip portion of the sensor holder 2, but a part of the exhaust gas introduction space L1 is formed in the tip portion of the sensor holder 2, and the rest. May be formed at the base end portion of the sensor holder 2.

The sensor unit 11 of the gas sensor 1 is fixed in the exhaust gas introduction space L1 in a state of being arranged. An exhaust gas introduction port for introducing exhaust gas from the flue LE into the exhaust gas introduction space L1 is formed at the tip of the sensor holder 2, and by providing a filter F at the exhaust gas introduction port, the flue LE and the above. It is partitioned from the exhaust gas introduction space L1.

Further, as shown in FIGS. 2 and 3, a multi-tube structure in which a plurality of tubes having different diameters are concentrically arranged is formed in a portion of the sensor holder 2 on the base end side of the exhaust gas introduction space L1. .. As shown in FIG. 3, the multi-tube structure includes an inner pipe 21, a partition pipe 22, and an outer pipe so that the cooling space L3, the heat insulating layer TB, and the calibration gas flow path L2 are formed from the inside to the outside. Three 23 are provided in this order from the inside. That is, as shown in FIG. 3, the torus-shaped (doughnut-shaped) heat insulating layer TB is arranged around the circular cooling space L3 in cross-sectional view, and further outside the heat insulating layer TB in cross-sectional view. A torus-shaped calibration gas flow path L2 is arranged.

The cooling space L3 is a cylindrical space formed inside the inner pipe 21 and accommodating the main body 12 of the gas sensor 1. As shown in FIG. 1, the cooling medium is introduced into the inside through the cooling medium introduction port 24 formed on the side surface near the base end of the inner pipe 21. For example, a gas adjusted to a low temperature as a cooling medium may be circulated in the cooling space L3 through the cooling medium introduction port 24 so that a predetermined temperature is maintained.

The calibration gas flow path L2 is a flow path formed in the sensor holder 2, and is a gas from the base end portion of the sensor holder 2 arranged outside the flue LE to the exhaust gas introduction space L1. It is a flow passage. In the present embodiment, the gas flow path is configured as a calibration gas flow path L2 for supplying the calibration gas to the exhaust gas introduction space L1. The calibration gas flow path L2 is configured so that the calibration gas flows along the axial direction in the outermost portion in the sensor holder 2 except for the vicinity of the exhaust gas introduction space L1. More specifically, the calibration gas is supplied to the exhaust gas introduction space L1 from the calibration gas introduction port 25 opened on the side surface of the outer pipe 23 at the base end portion of the sensor holder 2 arranged outside the flue LE. It is a flow path to be used. In the present embodiment, the calibration gas flow path L2 includes a flow path formed by a double pipe composed of the partition pipe 22 and the outer pipe 23, and a communication flow path L21 communicating with the exhaust gas introduction space L1. There is.

As shown in FIG. 1, the calibration gas flow path L2 is connected to the zero point adjusting gas supply source ZG and the span adjusting gas supply source SG via the calibration gas introduction port 25, respectively. The zero point gas supply source ZG and the span adjustment gas supply source SG are each provided with on-off valves, and which gas is supplied to the calibration gas flow path L2 or which gas is not supplied is determined. Can be controlled. The zero point adjusting gas is a gas that does not substantially contain a predetermined component detected by the gas sensor 1, and this gas is a purge gas for purging the gas in the calibration gas flow path L2 and the exhaust gas introduction space L1. Also used as. That is, in the present embodiment, the calibration gas flow path L2 and the purge gas flow path are not separately provided in the sensor holder 2 as in the conventional case, but are shared. The span adjusting gas contains a predetermined concentration of a predetermined component detected by the gas sensor 1 and is used for span calibration.

As shown in FIGS. 2 and 3, the heat insulating layer TB is, for example, an air layer formed between the inner peripheral surface of the partition pipe 22 and the inner peripheral surface of the inner pipe 21. The heat insulating layer TB can prevent the exhaust gas that may flow into the calibration gas flow path L2 from the exhaust gas introduction space L1 from being cooled by the cooling medium of the cooling space L3 during normal measurement. Here, the heat insulating layer TB is less likely to transfer heat than the state in which the pipe of the calibration gas flow path L2 and the inner pipe 21 forming the cooling space L3 are in close proximity as shown in FIGS. 5 and 6, for example. Can be defined as being. Further, the heat insulating layer TB may not be an air layer but may be further sealed with a filler such as a resin so as to further hinder the transfer of heat. Alternatively, the space between the inner pipe 21 and the partition pipe 22 may be solidified with metal to form at least one pipe thicker than the outer pipe 23.

The arithmetic processing unit COM realizes at least the functions of the correction processing unit 4 and the clogging determination unit 5 by executing the probe device program stored in the memory and collaborating with various devices.

The correction processing unit 4 corrects the output of the gas sensor 1 based on the output of the pressure sensor 3. For example, a correction coefficient using the pressure indicating the relationship between the value indicated by the output when the predetermined component of the predetermined concentration is detected by the gas sensor 1 and the pressure of the exhaust gas as a parameter is obtained in advance by an experiment or the like, and this correction is performed. The correction processing unit 4 corrects the output of the gas sensor 1 based on the coefficient and the pressure measured by the pressure sensor 3. That is, even if the exhaust gas flowing through the flue LE has a pressure fluctuation, the correction processing unit 4 converts the output value according to the concentration of the predetermined component.

The clogging determination unit 5 determines whether or not the filter F is clogged based on the measured pressure value indicated by the output of the pressure sensor 3 and a predetermined reference value. For example, a reference value is set based on the measured pressure value measured by the pressure sensor 3 in a state where the filter F is not clogged.

According to the probe device 100 and the exhaust gas analyzer 200 of the present embodiment configured in this way, the pressure sensor 3 monitors the pressure fluctuation of the exhaust gas flowing through the flue LE, and the correction processing unit 4 detects the pressure fluctuation. Since the correction is performed, the concentration of a predetermined component of the exhaust gas excluding the influence of pressure can be accurately obtained.

Further, at the time of calibration, the exhaust gas flowing through the calibration gas flow path L2 fluctuates according to the pressure fluctuation of the exhaust gas flowing through the flue LE. Since the pressure can be measured, such fluctuation can be corrected and the gas sensor 1 can be calibrated.

Further, since the clogging determination unit 5 monitors the measured pressure value indicated by the pressure sensor 3 to monitor the clogging state of the filter F, it is possible to automatically obtain the replacement time of the filter F. For example, in an application in which the state of the exhaust gas flowing through the flue LE greatly fluctuates, the filter F may be in a state unsuitable for measurement if the replacement time is set according to the period of use or the like. On the other hand, in the probe device 100, it is possible to detect that the filter F is clogged and the pressure of the exhaust gas after passing through the filter F is reduced, so that maintenance can be performed before a problem occurs in the measurement.

Since the calibration gas flow path L2 and the cooling space L3 are partitioned by the heat insulating layer TB, the high temperature at which the exhaust gas introduction space L1 flows through the flue LE in the calibration gas flow path L2. Even if the exhaust gas flows, it is not cooled to the extent that the water contained in the exhaust gas condenses. Therefore, it is possible to prevent nitrogen oxides and sulfides in the exhaust gas from being dissolved in the condensed water and becoming an acidic liquid to erode the outer pipe 23 or the partition pipe 22.

Further, since the calibration gas flow path L2 is arranged on the outermost side of the sensor holder 2 and a part of the calibration gas flow path L2 is arranged in the flue LE, the calibration gas flow path is arranged from the flue LE at the time of measurement. The exhaust gas flowing back to L2 can be warmed by the high-temperature exhaust gas flowing through the flue LE to prevent the condensation of water. On the other hand, at the time of calibration, the heat of the exhaust gas flowing in the flue LE can be transferred through the outer pipe 23 to warm the calibration gas. Therefore, more accurate calibration can be realized by bringing the calibration gas closer to the temperature at the time of actual measurement without using a heater or the like.

Since the pressure sensor 3 is provided in a flow path communicating with the calibration gas flow path L2, the pressure sensor 3 does not come into direct contact with the high-temperature exhaust gas flowing through the flue LE, and can be prevented from being damaged by heat. can.

In addition, since the main body 12 of the gas sensor 1 is arranged in the cooling space L3, even if a part of the gas sensor 1 is arranged in the flue LE, it is possible to prevent a failure from occurring due to a high temperature of the exhaust gas. can.

Next, other embodiments of the present invention will be described.

In the embodiment, the pressure sensor is provided in a flow path communicating with the calibration gas flow path, but for example, a pressure sensor may be provided in the calibration gas flow path.

The correction processing unit corrects the value indicated by the output of the gas sensor as a value on a computer based on the measured pressure value of the pressure sensor, but corrects the output signal itself output from the main body unit. It may be the one to be processed. Further, the gas sensor is not limited to one that outputs according to the concentration of a predetermined component, and may be a sensor that outputs according to other physical parameters.

In the above embodiment, the calibration gas flow path and the purge gas flow path are shared, but they may be divided into dedicated flow paths for each gas. Further, the pressure sensor is provided not only in the flow path for supplying the calibration gas or the purge gas to the exhaust gas introduction space. For example, a gas flow passage that communicates with the exhaust gas introduction space and reaches the base end portion located outside the flue in the sensor holder is separately provided, and calibration gas or purge gas is provided in the gas flow passage. You may not let it flow.

In the embodiment, the sensor holder has a triple tube structure including the inner tube, the partition tube, and the outer tube, but may be configured as a double tube structure including the inner tube and the outer tube, for example. That is, the inside of the inner pipe may be used as a cooling space for the gas sensor, and the space between the inner pipe and the outer pipe may be used as a calibration gas flow path. In this case, the thickness of the inner tube may be made thicker than that of the outer tube so as to exhibit the function as a heat insulating layer. Even in such a case, the high-temperature exhaust gas flowing through the calibration gas flow path is less likely to be cooled by the cooling medium introduced into the cooling space, preventing the condensation of water and preventing the generation of acidic liquids such as sulfuric acid. be able to. Further, the sensor holder does not have to have a coaxial multiplex structure, and for example, the inner tube may be eccentric with respect to the outer tube. The cross-sectional shape of the calibration gas flow path, which is the gas flow path, is not limited to the torus shape, and for example, a part is blocked between the outer pipe and the inner pipe, and the cross section of the gas flow passage is crossed. The surface shape may be formed in a partial annular shape such as a C shape.

In addition, various embodiments may be modified or combined as long as they do not contradict the gist of the present invention.

200 ・ ・ ・ Exhaust gas analyzer 100 ・ ・ ・ Probe device 1 ・ ・ ・ Gas sensor 11 ・ ・ ・ Sensor unit 12 ・ ・ ・ Main body 2 ・ ・ ・ Sensor holder 21 ・ ・ ・ Inner pipe 22 ・ ・ ・ Partition pipe 23 ・・ ・ Outer pipe L1 ・ ・ ・ Exhaust gas introduction space L2 ・ ・ ・ Calibration gas flow path L3 ・ ・ ・ Cooling space TB ・ ・ ・ Insulation layer 3 ・ ・ ・ Pressure sensor 4 ・ ・ ・ Correction processing unit 5 ・ ・ ・ Clog determination Department

Claims (9)

A probe device that samples the exhaust gas flowing through the flue.
The exhaust gas introduction space where the exhaust gas sampled from the flue is introduced, and
A gas sensor arranged in the exhaust gas introduction space and provided with a sensor unit that comes into contact with the exhaust gas,
A sensor holder that is provided so as to penetrate the inside and outside of the flue and holds the gas sensor inside.
A gas flow passage formed in the sensor holder and arranged outside the flue from the base end portion of the sensor holder to the exhaust gas introduction space.
A pressure sensor that measures the pressure at a position where the pressure fluctuation of the exhaust gas flowing through the flue can be monitored in the gas flow passage or the flow path communicating with the gas flow passage outside the flue.
A correction processing unit that corrects the output of the gas sensor based on the output of the pressure sensor is provided .
The gas flow path is a probe device that constitutes at least one of a calibration gas flow path and a purge gas flow path. The gas sensor further includes a main body portion held on the proximal end portion side of the sensor portion in the sensor holder.
It is further provided with a cooling space formed in the sensor holder to accommodate the main body of the gas sensor and to introduce a cooling medium.
The probe device according to claim 1, wherein a heat insulating layer is formed between the cooling space and the gas flow passage. The probe device according to claim 1, wherein at least a part of the gas flow passage is formed in the tip end portion of the sensor holder protruding into the flue. The sensor holder has a multi-tube structure including at least an inner tube and an outer tube.
The cooling space is formed inside the inner pipe, and the cooling space is formed.
The probe device according to claim 2 , wherein the gas flow passage is formed between the inner tube and the outer tube. The sensor holder further comprises a partition tube between the inner tube and the outer tube.
The probe device according to claim 4 , wherein the heat insulating layer is formed by a space between the outer surface of the inner tube and the inner surface of the partition tube. When looking at the cross section of the sensor holder,
The probe device according to claim 4 , wherein the gas flow passage is formed so as to surround the outer surface of the inner tube over the entire circumference. An exhaust gas introduction space in which at least a part is formed in the tip of the sensor holder protruding into the flue, the sensor portion of the gas sensor is accommodated, and exhaust gas is introduced from the flue.
A filter that separates the flue and the exhaust gas introduction space,
The probe device according to claim 1, further comprising a clogging determination unit for determining the presence or absence of clogging of the filter based on a measured pressure value indicated by an output of the pressure sensor and a predetermined reference value. The probe device according to claim 1 and
An exhaust gas analyzer including an analyzer main body that analyzes the exhaust gas flowing through the flue based on the output from the gas sensor. An exhaust gas introduction space into which the exhaust gas sampled from the flue gas is introduced, a gas sensor having a sensor unit arranged in the exhaust gas introduction space and in contact with the exhaust gas, and a gas sensor provided so as to penetrate the inside and outside of the flue gas. and a sensor holder for holding the gas sensor therein, a method of correcting the output of said gas sensor using a probe device for sampling the exhaust gas flowing through the flue,
A gas flow passage formed in the sensor holder and arranged outside the flue from the base end portion of the sensor holder to the exhaust gas introduction space , or a flow communicating with the gas flow passage outside the flue. A correction method for correcting the output of the gas sensor based on the output of a pressure sensor provided at a position where the pressure fluctuation of the exhaust gas flowing through the flue can be monitored on the road.

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