JP2010230582A - Exhaust gas measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust gas measuring device for analyzing dirt in an exhaust-gas connecting pipe simply and with high sensitivity. <P>SOLUTION: The exhaust gas measuring device 10 uses, as diluting air, refined air 12 obtained by refining taken-in air 11. The exhaust gas measuring device 10 has: an air refining apparatus 13 adjusting the temperature of the air 11 and pressure transmitting the air with the adjusted temperature as the refined air 12; a main path 17 through which the refined air 12 flows; an exhaust gas connecting pipe 18 feeding exhaust gas into the main path 17; an opening and closing valve 20 disposed downstream of a mixing part 19 in which the exhaust and refined air 12 are mixed, for opening or closing the inside of the main path 17; and a three-way valve 24 to which a first analysis line 22-1 branched from a connection part 21 of the exhaust gas connecting pipe 18, a second analysis line 22-2 branched from the main path 17, and a third analysis line 22-3 connected to an analyzer 23 that analyzes purge gas 12A taken into the first analysis line 22-1 or diluted exhaust gas taken into the second analysis line 22-2, are connected. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an exhaust gas measuring device for obtaining a discharge mass of a measurement target component of exhaust gas.

  2. Description of the Related Art Conventionally, in vehicles, an exhaust gas measuring device is used to measure and evaluate the exhaust mass of exhaust gas emitted from an engine. When measuring the emission mass of various components contained in the exhaust gas of automobiles, a constant volume sampling device (hereinafter referred to as “CVS device”) adopting a method called CVS (Constant Volume Sampler) due to its reliability and stability. Is used as an exhaust gas measuring device. In order to measure the emission mass from the exhaust gas diluted with air, the CVS device separately measures the measurement target component (background: BG) in the diluted air, and the difference between the measurement target component and the measurement target component of the exhaust gas. Obtain the mass discharged.

  Based on the above principle, a dummy test for supplying only air to the CVS device without connecting the vehicle exhaust pipe is performed, and the exhaust connection pipe is purged when checking the contamination state of the exhaust connection pipe in the CVS device. A method is used in which only the supplied air is collected and analyzed, and the dirt desorbed in the exhaust connection pipe is measured as the exhaust mass, thereby grasping the dirt state in the exhaust connection pipe.

  In addition, as a CVS device equipped with an air purifier, a line for taking in purified air discharged from the air purifier and a line for taking in air in the atmosphere are provided, and either purified air or air is selected. There has been proposed a method for obtaining exhaust mass of exhaust gas by using as dilution air (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 10-19744

  Here, with the recent development of multi-fuel vehicles, diversification of components to be measured, including unregulated components, and lower concentrations, more advanced measurement is required when measuring and evaluating exhaust connection pipe contamination in a CVS device. There is a need for a CVS device purge method with performance.

However, the moisture concentration in the exhaust gas discharged from a vehicle or the like using alcohol fuel or compressed natural gas (CNG) is, for example, 1.5 of a vehicle using a conventional fuel that has been conventionally used. It is as high as 2 to 2.0 times. Therefore, after the measurement of the exhaust gas emission mass using the CVS device is completed, condensed water tends to remain in the exhaust connection pipe, and alcohol, aldehyde, hydrocarbons containing oxygen in addition to this condensed water, NH ₃ , NO ₂ When the measurement target component such as is dissolved, the measurement target component remains in the exhaust connection pipe as persistent dirt. There is a problem that such a measurement target component is desorbed during a test for measuring the exhaust mass of exhaust gas discharged from another vehicle after the next time, thereby causing an error in the measurement value of the exhaust mass of exhaust gas.

  In particular, if the vehicle that measures the exhaust gas emission mass from the next time on is a low-emission vehicle, in order to accurately evaluate the low-emission vehicle, the measurement value error can be prevented and the exhaust gas emission mass can be measured more accurately. There is a need to do.

In addition, since the discharge rate of oxygen-containing compounds such as highly water-soluble alcohols and aldehydes has increased and the measurement target components including unregulated components have further diversified, highly water-soluble components such as NH ₃ Therefore, it is required to be measurable.

  In the CVS apparatus, in the purge method conventionally used for desorbing the measurement target component remaining in the exhaust connection pipe, as shown in FIG. 3, a dummy test for supplying only air to the CVS apparatus 100A is performed. At this time, since the amount of air 102 flowing through the exhaust connection pipe 101 is small and at a normal temperature or low temperature, the purge effect of the exhaust connection pipe 101 of the CVS device 100A is slight. Further, the state of the dirt measured as the exhaust mass is obtained by diluting the components that are gradually desorbed from the exhaust connection pipe 101 with the air 103, so that the dirt of the exhaust connection pipe 101 can be detected. Cannot be obtained. For this reason, in addition to the fact that the measurement target component desorbed from the exhaust connection pipe 101 is small, the air 102 supplied to the exhaust connection pipe 101 is diluted by, for example, several tens of times the air 103. There is a problem that it is not possible to detect dirt on the surface.

  Further, as shown in FIG. 4, in the CVS device 100B, in the purge method using a dilution air purifier and desorbing the measurement target component remaining in the exhaust connection pipe using the purified air, only the air is supplied to the CVS device 100B. When the air 102 flows from the exhaust connection pipe 101 when the dummy test is performed, the component to be measured in the purified air 111 is mistakenly recognized as dirt, and the inlet side of the exhaust connection pipe 101 is blocked by the plug 112. There is a problem that the purge effect of the exhaust connection pipe 101 cannot be obtained.

  Thus, with the recent development of multi-fuel vehicles, diversification of measurement target components including unregulated components, and lower concentrations, exhaust gas capable of analyzing the exhaust connection pipe dirt with higher accuracy in the CVS device. There is a need for a measuring device.

  The present invention has been made in view of the above, and it is an object of the present invention to provide an exhaust gas measuring device capable of easily analyzing dirt in an exhaust connection pipe with high sensitivity.

  The present invention for solving the above-described problems uses purified air that has been purified by taking in air in the atmosphere as dilution air, and exhaust gas discharged from the inspection object is mixed with the purified air, and diluted diluted exhaust gas is discharged. In the exhaust gas measuring device for measuring the mass and calculating the exhaust mass of the measurement target component exhausted from the exhaust gas, an air purifier that adjusts the temperature of the air taken in and pumps the temperature-adjusted air as purified air; and the air A main passage through which the purified air purified by a purifier is circulated; an exhaust connection pipe for feeding the exhaust gas discharged from the inspection object into the main passage; and an exhaust connection pipe for feeding the exhaust gas into the main passage from the exhaust connection pipe. An on-off valve provided downstream of a mixing section where the exhaust gas to be supplied and the purified air supplied from the air purifier are mixed, and capable of opening and closing the inside of the main passage; A first analysis line branched from a connection portion connected to the inspection object, a second analysis line provided downstream from the on-off valve, and branched from the main passage; A third analysis line connected to a measuring means for obtaining a discharge mass of a measurement target component contained in each of purified air purged from the analysis line or diluted exhaust gas collected from the second analysis line is connected to each other. An exhaust gas measuring device comprising: a gas flow path control means.

  According to the exhaust gas measuring apparatus according to the present invention, a large amount of purified air whose temperature is adjusted to a high temperature can be arbitrarily backflowed into the exhaust connection pipe as a purge gas, so that dirt in the exhaust connection pipe can be effectively purged and desorbed. By removing a part of the purge gas containing dirt and continuously feeding it directly to the analyzing means, the purge gas discharge mass can be directly and directly analyzed without diluting the purge gas containing the detached dirt. Therefore, the dirt state in the exhaust connection pipe can be easily measured with high sensitivity.

FIG. 1 is a diagram schematically showing the configuration of an exhaust gas measuring apparatus according to an embodiment of the present invention. FIG. 2 is a partially enlarged view of FIG. FIG. 3 is a diagram schematically showing a test performed by supplying air to the CVS apparatus. FIG. 4 is a diagram schematically showing a test performed by supplying purified air to the CVS apparatus.

  Hereinafter, an exhaust gas measuring device according to the present invention will be described in detail based on the drawings. Note that the present invention is not limited to the embodiments. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

[Embodiment]
FIG. 1 is a diagram simply showing a configuration of an exhaust gas measuring apparatus according to an embodiment of the present invention, and FIG. 2 is a partially enlarged view of FIG.

  The exhaust gas measuring apparatus 10 according to the present embodiment uses purified air 12 that has been purified by taking in air 11 in the atmosphere as dilution air, and mixes and dilutes exhaust gas discharged from a test vehicle (inspection object) with purified air 12. It is an exhaust gas measuring device that measures the discharge mass of the diluted exhaust gas and calculates the exhaust mass of the measurement target component exhausted from the exhaust gas. The exhaust gas measuring device 10 includes an air purifier 13 and a main passage (main duct) 17 through which the purified air 12 purified by the air purifier 13 is circulated.

  The air purifier 13 purifies the purified air 11 and purifies it, a temperature control unit (temperature control means) 15 that adjusts the temperature of the purified air 12 purified by the purification unit 14, and an air intake port. A blower (blower) 33 that takes in air 11 from the atmosphere 31 and sends it to the air outlet 32.

  The main passage 17 includes an exhaust connection pipe 18 that supplies the exhaust gas discharged from the test vehicle into the main passage 17, and the exhaust gas and air that are supplied from the exhaust connection pipe 18 into the main passage 17. An open / close valve (gas flow path control means) 20 that is provided on the downstream side of the mixing unit 19 that mixes with the purified air 12 supplied from the purifier 13 and that can be opened and closed.

  Further, the exhaust gas measuring device 10 has a three-way valve 24. The three-way valve 24 is provided on the downstream side of the first analysis line 22-1 where the exhaust connection pipe 18 is connected to the test vehicle 21 connected to the test vehicle and the on-off valve 20, and is branched from the main passage 17. The target component contained in each of the second analysis line 22-2, the purified air (purge gas) 12A purged from the first analysis line 22-1 or the diluted exhaust gas collected from the second analysis line 22-2. Are connected to a third analysis line 22-3 connected to an analyzer (measuring means) 23 for obtaining the discharged mass of each.

  Purified air 12 purified by taking in air 11 in the air in the air purifier 13 is used as dilution air. The main body 13a of the air purifier 13 has an air intake 31 and an air outlet 32 that are open to the atmosphere. Further, the blower 33 has a variable blowing capacity, and the air purifier 13 controls the flow rate so that the blower 33 blows the purified air 12 having an appropriate flow rate.

The air 11 blown to the blower 33 is supplied to the purification unit 14 and removes a measurement target component that is a regulated substance such as NOx such as total hydrocarbon (THC), CO, NO, NO ₂ contained in the air 11. . Further, the total hydrocarbon is the sum of both the concentration of methane (CH ₄ ) obtained by measurement of hydrocarbon (HC) in the atmosphere and the concentration of non-methane hydrocarbon (NMHC).

  A temperature control unit 15 is provided on the downstream side of the purification unit 14 in the main body 13a so that the temperature of the purified air 12 can be adjusted. For this reason, the temperature of the purified air 12 can be adjusted to a predetermined high temperature and blown into the main passage 17. The temperature of the purified air 12 is, for example, preferably in the range of 70 ° C. or higher and 90 ° C. or lower, and more preferably about 80 ° C. By setting the temperature of the purified air 12 to a high temperature, when the purified air 12 is supplied to the exhaust connection pipe 18, the component to be measured remaining in the exhaust connection pipe 18 is softened, and therefore remains in the exhaust connection pipe 18. It is possible to easily peel off the measurement target component from the exhaust connection pipe 18.

  In addition, the blower 33 pumps the purified air 12 from the air outlet 32 and discharges the diluted gas 11 at a pressure higher than the atmospheric pressure. May be provided so that the purified air 12 is pumped from the air outlet 32.

  The air outlet 32 is connected to the main passage 17 and introduces the purified air 12 purified by the air purifier 13 into the main passage 17 as dilution air. The main passage 17 has an intake port 35 for taking in the purified air 12 and an exhaust port 36 opened to the atmosphere, and is provided so as to communicate between the intake port 35 and the exhaust port 36. The intake 35 is configured to take in purified air 12 that is sent from the air outlet 32 of the air purifier 13 and blown. The purified air 12 is directly blown to the main passage 17, but the present invention is not limited to this, and a connection passage or the like is provided between the air purifier 13 and the main passage 17. Then, the purified air 12 may be blown into the main passage 17.

  A blower 37 (CVS suction device) for sucking the purified air 12 to the downstream side is disposed downstream of the main passage 17, and the purified air 12 is sucked to the downstream side from the intake 35. Further, a filter or a cyclone for removing dust may be disposed on the upstream side of the main passage 17.

  The main passage 17 is connected to the exhaust connection pipe 18. The exhaust connection pipe 18 is detachably connected to an exhaust pipe that discharges exhaust gas from an engine mounted on the test vehicle to the atmosphere. The main passage 17 includes a mixing unit 19 that mixes the exhaust gas fed from the exhaust connection pipe 18 to the main passage 17 and the purified air 12 in the main passage 17, and discharge mass of the measurement target component in the exhaust gas. During the measurement, the exhaust gas discharged from the engine of the test vehicle is mixed and diluted with the purified air 12 in the main passage 17 via the exhaust connection pipe 18 to obtain diluted exhaust gas.

  In addition, an on-off valve 20 that can open and close the main passage 17 is provided on the downstream side of the mixing unit 19. In this embodiment, the on-off valve 20 can be opened and closed in the main passage 17 in the same direction as the flow direction of the dilution gas 11, but may be opened and closed in the direction opposite to the flow direction of the dilution gas 11. The on-off valve 20 is opened when the exhaust connection pipe 18 is not purged, such as when measuring the discharge mass of the component to be measured in the exhaust gas, and is closed when the exhaust connection pipe 18 is purged. . The open / close state of the main passage 17 is adjusted by the open / close valve 20 using the driving device 38. When purging the inside of the exhaust connection pipe 18, the main passage 17 is closed by the on-off valve 20, whereby the purified air 12 supplied from the air purifier 13 is sent downstream from the on-off valve 20 of the main passage 17. To suppress. The pressure of the purified air 12 pumped from the air purifier 13 is higher than the atmospheric pressure in the vicinity of the mixing unit 19, and the purified air 12 is caused to flow back into the exhaust connection pipe 18 so as to flow back into the exhaust connection pipe 18. The inside of the exhaust connection pipe 18 can be purged using air as the purge gas 12A.

  In addition, the mixing section 19 of the main passage 17 is provided with a sensor 39 that detects the pressure in the main passage 17. The amount of purified air 12 fed to the downstream side of the on-off valve 20 is controlled by adjusting the degree of opening and closing.

  Further, the first analysis line 22-1 branched from the connection portion 21 of the exhaust connection pipe 18, the second analysis line 22-2 branched from the main passage 17 downstream from the on-off valve 20, and the first The third analysis connected to the analyzer 23 for obtaining the discharge mass of the measurement target component contained in each of the purge gas 12A collected from the analysis line 22-1 or the diluted exhaust gas collected from the second analysis line 22-2. Lines 22-3 are connected to each other by a three-way valve 24.

  The three-way valve 24 opens a flow path in three directions in one valve, and has an outlet in one direction with respect to an inlet from two directions. The three-way valve 24 includes two inlets connected to the first analysis line 22-1 and the second analysis line 22-2, and one outlet connected to the third analysis line 22-3. By purging the exhaust connection pipe 18 by connecting the first analysis line 22-1 and the third analysis line 22-3, the purge gas 12A in which the purified air 12 is caused to flow back into the exhaust connection pipe 18 is exhausted. It can be fed to the analyzer 23 from the connection portion 21 of the connection pipe 18 via the first analysis line 22-1 and the third analysis line 22-3. For this reason, since the purge gas 12A can be directly and continuously analyzed by the analyzer 23 without diluting the purified air 12, analysis of dirt in the exhaust connection pipe 18 can be easily performed with high sensitivity.

An example of control when analyzing dirt in the exhaust connection pipe 18 is shown.
The purge gas 12A used for purging in the exhaust connection pipe 18 is supplied to the analyzer 23 via the first analysis line 22-1 and the third analysis line 22-3, and the concentrations of THC and NOx in the purge gas 12A are supplied. Measure.

  When the concentrations of THC and NOx of the purge gas 12A measured by the analyzer 23 become 0.2 ppm or less within a predetermined time (for example, 10 minutes), the purified air 12 is put into the exhaust connection pipe 18. The purging of the exhaust connection pipe 18 is ended by making the flow reverse.

  If the respective concentrations of THC and NOx in the purge gas 12A measured by the analyzer 23 are not 0.2 ppm or less within a predetermined time (for example, 10 minutes), the three-way valve 24 causes the second analysis. The line 22-2 and the third analysis line 22-3 are switched to each other, and the purified air 12 is extracted from the second analysis line 22-2 branched from the main passage 17 downstream from the on-off valve 20. The gas is fed to the analyzer 23 via the second analysis line 22-2 and the third analysis line 22-3, and the exhaust mass of the purified air 12 is obtained by the analyzer 23. The concentrations of THC and NOx in the purge gas 12A extracted from the connection portion 21 of the exhaust connection pipe 18 to the first analysis line 22-1 and the purified air extracted from the main passage 17 to the second analysis line 22-2. When the difference between the concentrations of THC and NOx in 12 is within the range of 0.1 ppm or more and 0.1 ppm or less, the purging of the exhaust connection pipe 18 with the purified air 12 is terminated.

  As described above, when the respective concentrations of THC and NOx in the purge gas 12A are larger than 0.2 ppm, or each of the THC and NOx in the purge gas 12A extracted from the connection portion 21 to the first analysis line 22-1 And the difference between the concentration of THC and NOx in the purified air 12 extracted from the main passage 17 to the second analysis line 22-2 is in the range of -0.1 ppm or more and 0.1 ppm or less. If not, the above operation is repeated. As a result of repeating the above operation again, if none of the above conditions is satisfied, the exhaust connection pipe 18 and other devices are inspected.

  Therefore, a large amount of purified air 12 whose temperature is adjusted to a high temperature is caused to flow back into the exhaust connection pipe 18 as a purge gas 12A, and the purge gas 12A containing desorbed dirt is effectively purged by removing the dirt in the exhaust connection pipe 18 effectively. Can be directly analyzed by the analyzer 23 without diluting, so that the dirt state in the exhaust connection pipe 18 can be easily measured with high sensitivity.

  Further, in the exhaust gas measuring apparatus 10 according to the present embodiment, the on-off valve 20 is closed to cause the purified air 12 to flow backward to the exhaust connection pipe 18, and the purged air 12 that has flowed back is used as the purge gas 12A to purge the inside of the exhaust connection pipe 18 However, the present invention is not limited to this, and the blower 37 may be stopped to allow the purified air 12 to flow backward to the exhaust connection pipe 18 and to purge the exhaust connection pipe 18. Good.

  Further, a venturi 41 is provided upstream of the blower 37 and between the blower 37 and the on-off valve 20, and when the exhaust mass of the measurement target component of the exhaust gas discharged from the test vehicle is analyzed, The purified air 12 is set to an appropriate dilution rate. The venturi 41 allows the diluted exhaust gas obtained by mixing the exhaust gas and the purified air 12 to flow through the main passage 17 at a constant flow rate.

  In addition, as a CVS apparatus, two systems of a constant capacity pump system (PDP system) and a critical flow venturi system (CFV system) are adopted. In the exhaust gas measuring apparatus 10 according to the present embodiment, a CFV type CVS apparatus using a venturi 41 is employed, but a positive displacement pump (PDP) type CVS apparatus is used instead of the CFV type. May be.

  A sampling venturi 42 is provided on the upstream side of the venturi 41, and the purified air 12 is collected from the sampling venturi 42 at a constant flow rate by the suction force of the suction pump 43 disposed outside the main passage 17. The bag 44 is stored. When measuring the emission mass of the measurement target component in the exhaust gas, the diluted exhaust gas obtained by diluting the exhaust gas with the purified air 12 is stored in the sample bag 44 so as to obtain the average concentration of the measurement target component in the exhaust gas. I have to.

Further, between the intake 35 of the main passage 17 and the mixing section 19, only the purified air 12 is collected by the suction pump 45 through the branch passage 46 and stored in the dilution air bag 47. While measuring the emission mass of the measurement target component in the exhaust gas, the measurement target component such as THC such as CH ₄ remaining in the purified air 12, NOx such as CO, NO, NO ₂ is stored.

  The gas in the sample bag 44 and the dilution air bag 47 is analyzed by the analyzer 23 to obtain the concentration of the measurement target component in the exhaust gas. Specifically, the analyzer 23 subtracts the measurement target component in the purified air 12 collected by the dilution air bag 47 from the measurement target component in the diluted exhaust gas collected by the sample bag 44, for example, from the test vehicle. Obtain the emission mass of the measurement target component in the exhaust gas.

  Further, the analyzer 23 is provided with an exhaust passage for discharging the purge gas 12A used for the analysis, the purified air 12, and the diluted exhaust gas into the main passage 17 on the downstream side of the venturi 41. The purge gas 12A, the purified air 12, and the diluted exhaust gas used for analysis by the analyzer 23 are fed into the main passage 17 downstream of the venturi 41 through the exhaust passage.

  As described above, according to the exhaust gas measuring apparatus 10 according to the present embodiment, a large amount of purified air 12 whose temperature has been adjusted to a high temperature is arbitrarily flown back into the exhaust connection pipe 18 as the purge gas 12A. Dirt can be effectively purged. A part of the purge gas 12A including the desorbed dirt is extracted and continuously supplied directly to the analyzer 23, so that the discharge mass of the purge gas 12A can be directly and continuously reduced without diluting the purge gas 12A including the desorbed dirt. Since it can be analyzed, the dirt state in the exhaust connection pipe 18 can be easily measured with high sensitivity.

  Accordingly, it becomes possible to grasp the dirt state of the exhaust connection pipe 18 which has been difficult with the CVS purge method using the conventional air purifier, and in the exhaust of alcohol fuel, compressed natural gas vehicle, etc. in the recent multi-combustion. As the moisture concentration of the exhaust gas is high, the condensed water in which the measurement target component is dissolved in the exhaust connection pipe 18 is likely to remain, the diversification of the measurement target component including the unregulated component, and the lower concentration, the weight of the measurement target component of exhaust gas At the time of measurement, the influence of dirt on the exhaust pipe 18 in the CVS device can be eliminated, analysis can be performed with higher accuracy, and measurement reliability can be improved. In addition, it is possible to ensure measurement reliability when measuring the weight of the measurement target component of the exhaust gas discharged from the low emission vehicle.

  In the exhaust gas measurement device 10 according to the present embodiment, the case where the exhaust gas measurement device for obtaining the weight of the measurement target component in the exhaust gas from the vehicle is used as the inspection target is described, but the present invention is limited to this. Instead, the purge of the measuring device for obtaining the weight of the component in the exhaust gas discharged from other than the vehicle may be used similarly.

  As described above, the exhaust gas measuring apparatus according to the present invention purges the measurement target component remaining in the exhaust connection pipe using purified air and continuously analyzes it directly. Therefore, analysis of dirt in the exhaust connection pipe Is suitable for use in an exhaust gas measuring device for determining the weight of exhaust gas in exhaust gas discharged from a vehicle.

10 Exhaust gas measuring device 11 Air 12 Purified air (diluted air)
12A Purge gas 13 Air purifier 14 Purification unit 15 Temperature control unit (temperature control means)
17 Main passage (main duct)
18 Exhaust connection pipe 19 Mixing section 20 On-off valve (gas flow path control means)
21 connecting part 22-1 first analysis line 22-2 second analysis line 22-3 third analysis line 23 analyzer (measuring means)
24 Three-way valve 31 Air inlet 32 Air outlet 33 Blower (blower)
35 Inlet 36 Outlet 37 Blower (CVS suction device)
38 Drive Device 39 Sensor 41 Venturi 42 Sampling Venturi 43 Suction Pump 44 Sample Bag 45 Suction Pump 46 Branch Passage 47 Dilution Air Bag

Claims (1)

Measurement using the purified air purified by taking in air in the atmosphere as dilution air, mixing the exhaust gas discharged from the test object with the purified air, measuring the discharge mass of the diluted diluted exhaust gas, and discharging from the exhaust gas In the exhaust gas measurement device that calculates the emission mass of the target component,
An air purifier that adjusts the temperature of the air taken in and pumps the temperature-adjusted air as purified air;
A main passage through which the purified air purified by the air purifier flows.
An exhaust connection pipe for feeding the exhaust gas discharged from the inspection object into the main passage;
Provided on the downstream side of a mixing section where the exhaust gas fed from the exhaust connection pipe into the main passage and the purified air supplied from the air purifier are mixed, and the inside of the main passage can be opened and closed. An opening and closing valve,
A first analysis line branched from a connection portion where the exhaust connection pipe is connected to the inspection object; a second analysis line provided downstream from the on-off valve; and branched from the main passage; A third analysis line connected to a measuring means for obtaining a discharge mass of a measurement target component contained in each of purified air purged from one analysis line or diluted exhaust gas collected from the second analysis line; Coupled gas flow path control means;
An exhaust gas measuring device characterized by comprising:

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