JP4879053B2 - Exhaust gas analyzer - Google Patents

Description

  The present invention relates to a technology of an exhaust gas analyzer, and more particularly, to an exhaust gas analyzer equipped with a sensor unit that is attached to an exhaust path for exhausting exhaust gas from an internal combustion engine and measures the component concentration of the exhaust gas in the exhaust path. Related to improved technology.

  Conventionally, as a device for measuring and analyzing the concentration and temperature of exhaust gas discharged from an internal combustion engine such as an engine of an automobile, a sensor unit including a light source, a detector unit, and the like is provided in an exhaust path (pipe). A configuration of an exhaust gas analyzer that is directly arranged and configured to measure a component concentration in exhaust gas in real time by detecting laser light transmitted through the exhaust gas flowing through the exhaust path by such a sensor unit. It is publicly known (see, for example, Patent Document 1).

The exhaust gas analyzer disclosed in Patent Document 1 described above irradiates laser light toward an exhaust gas passage hole through which exhaust gas discharged from an internal combustion engine passes, and after multiple reflections of the laser light by a reflecting mirror, There is provided a sensor unit for detecting the laser beam that has passed through. And this sensor part carries out multiple reflection of a laser beam by a pair of reflecting mirrors which oppose in the exhaust gas passage hole of a sensor main part, and secures the distance (measurement length) which laser beam penetrates in exhaust gas longer. It is configured to improve its measurement accuracy.
JP 2006-184180 A

  By the way, in the exhaust gas analyzer disclosed in Patent Document 1 described above, the sensor unit described above is disposed between the cylinder head of the engine and the exhaust manifold, and the exhaust gas immediately after being exhausted from the engine is merged by the exhaust manifold. A configuration for measuring the temperature and gas concentration of exhaust gas at the previous stage is disclosed.

  Indeed, since the exhaust gas discharged from each cylinder can be analyzed by directly measuring the temperature and gas concentration of the exhaust gas discharged from each cylinder of the engine, the combustion state of the engine can be confirmed for each cylinder. In particular, in recent engine development, improvement of fuel efficiency and emission performance is an issue in order to make the product highly productive, and engine supply and exhaust gas are accurately measured for instantaneous fuel efficiency evaluation and emission evaluation. It is preferred to be able to do so.

However, in the configuration of the exhaust gas analyzer described above, a multiple reflection method using a reflecting mirror has been adopted in the sensor unit in order to secure the optical path length of the laser light irradiated toward the exhaust gas passage hole. There were the following problems.
In other words, the sensor unit is arranged between the cylinder head of the engine and the exhaust manifold, so that it receives the influence (heat radiation and heat transfer) of the high-temperature exhaust gas (800 ° C to 1000 ° C) immediately after being discharged from the engine. In the reflecting mirror provided in the section, there is a problem that the reflective coating for multiple reflection of the measurement laser light having a relatively low heat-resistant temperature (500 ° C. to 600 ° C.) is damaged and the measurement accuracy of exhaust gas is inferior. there were.

  Further, in the sensor unit, there is a possibility that the sensor main body and each member constituting the sensor are subjected to temperature deformation (thermal distortion or thermal deformation) under the influence of the high-temperature exhaust gas immediately after being discharged from the engine. When the sensor body and each member constituting the sensor unit are deformed by temperature, the reflecting mirror is loosely fixed, the reflection angle of the laser beam irradiated from the irradiation unit is shifted, and the laser beam is received by the light receiving unit. It was a cause of measurement failure such as inability to receive light.

  Furthermore, in the first place, the use of a reflecting mirror in the sensor unit has a problem in that the configuration of the sensor unit is complicated and inferior in maintainability, and the manufacturing cost is high.

  Therefore, the present invention relates to an exhaust gas analyzer, which solves the above-described conventional problems, and provides an exhaust gas analyzer that can accurately and stably measure the exhaust gas component concentration with a simple configuration. It is for the purpose.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

That is, in claim 1, in the exhaust gas analyzer that includes a sensor unit that is attached to an exhaust path for exhausting exhaust gas from an internal combustion engine and that measures a component concentration of the exhaust gas in the exhaust path, the sensor unit includes the internal combustion engine. A sensor main body in which a plurality of exhaust gas passage holes through which exhaust gas from an engine passes are formed along a predetermined direction, an irradiation unit that irradiates laser light in a direction crossing the plurality of exhaust gas passage holes, and the irradiation And a light receiving unit that receives the laser light emitted from the unit.

  According to a second aspect of the present invention, the sensor main body is provided with a light passage hole communicating between the adjacent exhaust gas passage holes along the optical path of the laser light emitted from the irradiation unit.

  According to a third aspect of the present invention, the sensor main body is provided with a laser light transmitting lens member that divides a region in the exhaust gas passage hole and a region in the light passage hole in the light passage hole.

  According to a fourth aspect of the present invention, the sensor main body is provided with a gas supply / discharge path for supplying / discharging inert gas in a region within the light transmission hole.

  As effects of the present invention, the following effects can be obtained.

  Since it was set as the structure shown in Claim 1, it can measure the component density | concentration of waste gas accurately and stably with a simple structure.

  Since it is set as the structure shown in Claim 2, by attaching a pair of irradiation part and light-receiving part with respect to a sensor main body, a laser beam can be irradiated so that all the exhaust gas passage holes may be crossed, and a sensor structure is simplified. Can be configured.

  Since it was set as the structure shown in Claim 3, it can prevent that the waste gas in a waste gas passage hole stays in the area | region in a light transmission hole, and the component density | concentration of a residence gas overlaps with the result of the density | concentration measurement of an original waste gas, or It is possible to prevent the measurement accuracy from being reduced due to noise generated during concentration measurement due to fluctuations in the component concentration of the staying gas.

  Since the structure shown in claim 4 is used, the accumulated gas in the light transmission hole can be discharged out of the apparatus by the inert gas, and the component concentration of the accumulated gas overlaps with the original measurement result of the exhaust gas concentration, or the accumulated gas The measurement accuracy of exhaust gas can be improved by the noise generated when the concentration of the component fluctuates and the concentration is measured.

Next, the best mode for carrying out the invention will be described.
FIG. 1 is a side view showing an overall configuration of an exhaust gas analyzer according to an embodiment of the present invention, FIG. 2 is a perspective view showing the configuration of an exhaust gas analysis sensor of the present embodiment, and FIG. FIG. 4 is a front sectional view of the sensor for exhaust gas analysis of the present embodiment, FIG. 5 is an enlarged sectional view showing the mounting structure of the irradiation unit, and FIG. 6 is a light receiving unit. FIG. 7 is an enlarged sectional view showing the vicinity of the light passage hole, and FIG. 8 is an enlarged sectional view showing the vicinity of the light passage hole of the sensor for exhaust gas analysis of another embodiment. It is.

First, the overall configuration of the exhaust gas analyzer 1 of the present embodiment will be outlined below.
As shown in FIG. 1, the exhaust gas analyzer 1 of the present embodiment measures and analyzes the component concentration and temperature in exhaust gas discharged from an engine 20 that is an internal combustion engine disposed in an automobile 2. Specifically, the exhaust gas analyzing apparatus 1 includes an exhaust gas analyzing sensor 4 as a sensor unit that measures the component concentration of the exhaust gas in the exhaust path 3 at a plurality of locations in the exhaust path 3 of the exhaust gas extended from the engine 20. 5, a laser transmitting / receiving controller 10 connected to the exhaust gas analysis sensors 4, 5, a computer device 11 connected to the controller 10, and the like.

  The automobile 2 is provided with an exhaust path 3 for discharging exhaust gas from the engine 20 to the outside of the machine. The exhaust path 3 includes an exhaust manifold 30, an exhaust pipe 31, a first catalyst device 32, a second catalyst device 33, and a muffler 34. And the exhaust pipe 35 and the like. In addition, each component device of the exhaust path 3 is connected by a pipe 3a having a circular cross section.

  In the exhaust path 3, the exhaust gas of the engine 20 is first merged in the exhaust manifold 30, introduced into the first catalyst device 32 and the second catalyst device 33 through the exhaust pipe 31, and then into the atmosphere from the exhaust pipe 35 through the muffler 34. Released. By forming such an exhaust path 3, the exhaust gas from the engine 20 is purified by the two catalytic devices 32 and 33, muffled and decompressed by the muffler 34, and released into the atmosphere.

  In the exhaust path 3, exhaust gas analysis sensors 4 are arranged at four locations. Specifically, the first catalyst device is provided between the exhaust pipe 31 upstream of the first catalyst device 32 and the first catalyst device 32. 32 and the second catalyst device 33, between the second catalyst device 33 and the muffler 34, and at the end of the exhaust pipe 35. In the present embodiment, the exhaust gas analysis sensor 5 is disposed between the engine 20 and the exhaust manifold 30 (see FIG. 4).

  In the exhaust gas analyzer 1 of the present embodiment, each of the exhaust gas analysis sensors 4 and 5 receives the infrared laser light from the controller 10 and receives the laser light after passing through the exhaust gas. The controller 10 sends the computer apparatus 11 to analyze the components in the exhaust gas.

The controller 10 is an irradiation device that irradiates infrared laser light having a plurality of wavelengths, and the wavelength of the laser light is set according to the component of the exhaust gas to be detected. Further, the controller 10 is provided with a differential type photodetector (not shown) connected to the exhaust gas analysis sensors 4 and 5 so that the signal light received by the exhaust gas analysis sensors 4 and 5 is guided. Then, the signal light of the laser light transmitted through the exhaust gas and attenuated and the laser light not transmitted through the exhaust gas is output to the computer device 11 connected thereto.
The computer apparatus 11 analyzes the output signal from the controller 10 to analyze the exhaust gas by calculating the component concentration of the exhaust gas and the temperature of the exhaust gas.

  Thus, in the exhaust gas analyzer 1 of the present embodiment, spot exhaust gas can be measured on one section of the exhaust path 3 by the exhaust gas analyzing sensors 4 and 5. In particular, as in the present embodiment, the exhaust gas analysis sensors 4 and 5 are provided at a plurality of locations in the exhaust path 3 to instantaneously measure how the exhaust gas changes in a predetermined section of the exhaust path 3. The exhaust gas state can be continuously measured in real time.

Next, the configuration of the exhaust gas analysis sensor 5 will be described in detail below.
As shown in FIGS. 2 to 6, the exhaust gas analyzing sensor 5 of the present embodiment is formed of a long plate-like member having a substantially rectangular shape in plan view, and circular exhaust gas passage holes 51, 51. Each of the exhaust gas passage holes 51, 51,... Is formed along a cross section orthogonal to the sensor main body 50 and the exhaust gas passage holes 51, 51,. An irradiation unit 6 that irradiates laser light in a transverse direction, a light receiving unit 7 that receives laser light emitted from the irradiation unit 6, and the like are disposed between the engine 20 and the exhaust manifold 30. The

First, the configuration of the sensor body 50 will be described in detail below.
As shown in FIG. 2, the sensor main body 50 is formed as a machine base that constitutes the exhaust gas analysis sensor 5, and is specifically composed of a long plate-like metal member formed in a substantially rectangular shape in plan view. The circular exhaust gas passage holes 51, 51,... Are drilled at a plurality of locations (four locations in the present embodiment) so as to penetrate through the opposing surface orthogonal to the flow direction. Each exhaust gas passage hole 51 is opened on the same plane, and the exhaust gas passage holes 51 and 51 adjacent to each other have a predetermined spacing so that the exhaust gas passage holes 51 are flat along the longitudinal direction (left and right direction in FIG. 2) of the sensor body 50. It is pierced so as to be positioned substantially on the same line.

  Hereinafter, the exhaust gas passage hole 51 formed in the sensor body 50 is distinguished as the exhaust gas passage holes 51 at positions P1 to P4 along the longitudinal direction in order from one end surface in the longitudinal direction (the leftmost end surface in FIG. 2). I decided to. However, the exhaust gas passage holes 51 at the positions P1 to P4 are formed substantially the same.

  As shown in FIG. 3, the sensor 5 for exhaust gas analysis of the present embodiment is attached between the cylinder head 20a of the four-cylinder engine 20 and the exhaust manifold 30. Specifically, the sensor body 50 is shown on both sides. It is sandwiched and fixed between the cylinder head 20a and the exhaust manifold 30 with a gasket (not shown) in contact therewith. In the exhaust manifold 30, the flange 30a at the upstream end of the exhaust path 3 is fastened to the cylinder head 20a by a bolt (not shown) or the like. Further, the downstream end portion of the exhaust passage 3 of the exhaust manifold 30 is connected to the pipe joint 36 described above to form the exhaust passage 3.

  The exhaust gas analyzing sensor 5 according to the present embodiment includes the exhaust gas passage holes 51, 51, and 52 in the sensor body 50 at positions corresponding to the number of cylinders of the engine 20, that is, the four exhaust holes 20b provided in the cylinder head 20a.・ ・ Is drilled. Since the exhaust gas passage hole 51 is formed at such a position, the exhaust gas discharged from each exhaust hole 20b by the exhaust gas analyzing sensor 5 attached between the cylinder head 20a and the exhaust manifold 30 is placed at a corresponding position. The component concentration can be measured when passing through the provided exhaust gas passage hole 51.

  As shown in FIGS. 2 and 4, the sensor main body 50 includes a plurality of light passage holes 52, 52, which communicate with adjacent exhaust gas passage holes 51 along the optical path of the laser light emitted from the irradiation unit 6. Is provided. Specifically, the light passage hole 52 is penetrated so as to continue the space of the adjacent exhaust gas passage hole 51 every time the adjacent exhaust gas passage holes 51 are separated. Each light passage hole 52 is formed so as to follow a cross section orthogonal to the exhaust gas passage hole 51. In the present embodiment, each light passage hole 52 is on the same line along the optical path of the laser light emitted from the irradiation unit 6, that is, along one cross section orthogonal to the exhaust gas passage hole 51 in the sensor body 50. It is provided to be located.

  As shown in FIGS. 4 to 6, the sensor body 50 is provided with a light passage hole 53 that communicates the exhaust gas passage holes 51 at the positions P1 and P4 with the external spaces on both end surfaces in the longitudinal direction. An exhaust gas passage hole 51 at positions P 1 and P 4 is in communication with the outside of the sensor body 50 through 53. The light-transmitting holes 53 of the present embodiment are provided so as to be located on the same line as the above-described light-transmitting holes 52, that is, on the same line that crosses the sensor main body 50 along one cross section orthogonal to the exhaust gas passage hole 51. It is done.

  In the light transmission hole 53, a gasket 54 and a lens member 55 for transmitting laser light are disposed in order from the innermost part (the inner part on the exhaust gas passage hole 51 side) toward the outer side. The lens member 55 is in close contact with the inner wall of the light passage hole 53, the exhaust gas passage hole 51 and the external space are shielded, and the exhaust gas in the exhaust gas passage hole 51 does not leak outside through the light passage hole 53. It is configured as follows.

  The gasket 54 and the lens member 55 are positioned and fixed to the sensor main body 50 by coaxial bolts 56. Further, a hole for passing a laser beam is formed at a position located on the optical axis of the laser beam, which is the axial center of the gasket 54 and the coaxial bolt 56. Laser light emitted from the irradiation unit 6 to be described later is introduced into the exhaust gas passage hole 51 through the lens member 55 and is led out of the exhaust gas passage hole 51 through the lens member 55 and received by the light receiving unit 7. Is done.

Next, the structure of the irradiation part 6 and the light-receiving part 7 is explained in full detail below.
As shown in FIGS. 4 and 5, the irradiation unit 6 includes an optical fiber 60 for infrared transmission, and a connection block 61 that positions and attaches the optical fiber 60 to the sensor body 50. One end of the optical fiber 60 is connected to an incident light collimator 61 a provided in the connection block 61, and the other end is connected to the controller 10 described above, and laser light emitted from the controller 10 passes through the optical fiber 60. It is irradiated from the incident light collimator 61a.

  The connection block 61 is fastened by a bolt 64 while being in contact with one end surface of the sensor body 50 via an alignment adjusting plate 62 formed of a ceramic plate and a heat insulating plate 63 formed of a ceramic material. The connection block 61 is provided with a light passage hole 65 that is linearly connected to the light passage hole 53 while being attached to the light passage hole 53 formed in one end surface of the sensor body 50. .

  In the irradiation unit 6 of this embodiment, the irradiation surface of the optical fiber 60 is opposed to the exhaust gas passage hole 51 via the light passage hole 65 and the light passage hole 53, and the light passage hole 65 and the light passage hole 53 are used. The laser beam is attached to the sensor main body 50 so as to be able to irradiate a cross section orthogonal to the exhaust gas passage hole 51 and to irradiate in a direction crossing each exhaust gas passage hole 51. Yes.

  As shown in FIGS. 4 and 6, the light receiving unit 7 is configured substantially the same as the irradiation unit 6 described above, and includes a detector 70 that detects laser light, and a connection block 71 that positions and attaches the detector 70 to the sensor body 50. Etc. One end of the detector 70 is connected to the light receiving collimator 71a provided in the connection block 71, and the other end is connected to the controller 10 described above, and the laser light transmitted through the exhaust gas is received by the detector 70, A light reception signal is input to the controller 10.

  The connection block 71 is fastened by a bolt 74 while being in contact with the other end surface of the sensor body 50 via an alignment adjusting plate 72 formed of a ceramic plate and a heat insulating plate 73 formed of a ceramic material. The connection block 71 is provided with a light passage hole 75 that is linearly connected to the light passage hole 53 while being attached to the light passage hole 53 formed in the other end surface of the sensor body 50. .

  In the light receiving unit 7 of the present embodiment, the light receiving surface of the detector 70 is opposed to the exhaust gas passage hole 51 through the light passage hole 75 and the light passage hole 53, and is orthogonal to the exhaust gas passage hole 51 from the irradiation unit 6 as described above. The laser beam irradiated in the direction crossing each exhaust gas passage hole 51 along one cross section to be received on the same line as the irradiation unit 6 so that it can be received through the light transmission hole 53 and the light transmission hole 75 It is attached to the sensor main body 50 so as to be positioned.

  As described above, the sensor 5 for exhaust gas analysis according to the present embodiment crosses the exhaust gas passage holes 51, 51... Along the cross section orthogonal to the exhaust gas passage hole 51 by the irradiation unit 6 and the light receiving unit 7. An optical path of laser light is formed toward the surface. The sensor body 50 of the exhaust gas analysis sensor 5 is provided with the above-described light passage hole 52 and other light passage holes 53 along the optical path of the laser light.

In the exhaust gas analyzer 1 of the present embodiment, when measuring the component concentration of the exhaust gas passing through each exhaust gas passage hole 51 by the exhaust gas analysis sensor 5, first, the irradiation unit 6 is orthogonal to the exhaust gas passage hole 51. A laser beam is irradiated along the cross section in a direction crossing each of the exhaust gas passage holes 51, 51... And introduced into the exhaust gas passage hole 51 at the position P1 through the light passage hole 53 and the like.
And the laser beam introduced into the exhaust gas passage hole 51 at the position P1 passes through the exhaust gas to the exhaust gas passage holes 51 at the adjacent positions P2 and P3 through the light passage holes 52, 52. And finally reach the exhaust gas passage hole 51 at the position P4.
The laser beam derived from the exhaust gas passage hole 51 at the position P4 through the light passage hole 53 and the like is received by the light receiving unit 7 arranged on the same line as the irradiation unit 6.

Next, the lens member 90 provided in the light transmission hole 52 will be described below.
As shown in FIGS. 4 and 7, the sensor 5 for exhaust gas analysis of the present embodiment has a region (exhaust gas region D1) in the exhaust gas passage hole 51 in each light passage hole 52, 52. Laser light transmitting lens members 90 and 90 for partitioning a region in the light passage hole 52 (sensor inner region D2) are provided. Specifically, the lens members 90 and 90 are respectively disposed at both opening ends of the light passage hole 52 on the side of the exhaust gas passage hole 51 so as to partition the boundary between the exhaust gas passage hole 51 and the light passage hole 52. The

  The lens member 90 is fixed to the inner end of the sensor main body 50 by a fixing bolt 92 via a gasket 91 as viewed from the opening end of the light passage hole 52 and viewed from the opening end on the exhaust gas passage hole 51 side. Thus, by attaching the pair of lens members 90 and 90 to the light transmission hole 52, the space formed by the exhaust gas passage hole 51 and the light transmission hole 52 in the sensor main body 50 is the exhaust gas region D 1 and the inner region D 2. It is divided into a plurality of areas.

  When the laser light emitted from the irradiation unit 6 passes through each light passage hole 52, the laser light is introduced from the exhaust gas region D1 into the internal region D2 through the one lens member 90, and after passing through the internal region D2. Then, it is led out from the internal region D2 to the exhaust gas region D1 through the other lens member 90.

  Each lens member 90 is in close contact with the inner wall of the light passage hole 52, and shields the exhaust gas passage hole 51 and the inside of the light passage hole 52, that is, the exhaust gas region D 1 and the inner region D 2, thereby exhaust gas passage hole 51. The exhaust gas inside (exhaust gas region D1) is configured not to leak into the light transmission hole 52 (internal region D2).

  As described above, the exhaust gas analyzer 1 according to the present embodiment is attached to the exhaust path 3 for discharging the exhaust gas of the engine 20 and includes the exhaust gas analysis sensor 5 that measures the component concentration of the exhaust gas in the exhaust path 3. In the analyzer, the sensor 5 for exhaust gas analysis includes a sensor main body 50 in which a plurality of exhaust gas passage holes 51, 51... Through which exhaust gas from the engine 20 passes are formed along the longitudinal direction, and each exhaust gas passage hole 51. -Since it has the irradiation part 6 which irradiates a laser beam toward the direction crossing 51 ..., and the light-receiving part 7 which light-receives the laser beam irradiated from the irradiation part 6, it is exhaust gas by simple structure. Can be measured accurately and stably.

  That is, in the exhaust gas analyzing apparatus 1 of the present embodiment, the exhaust gas analyzing sensor 5 is provided with a reflecting mirror in the exhaust gas analyzing sensor 5 as in the prior art, and the laser light is multiple-reflected, thereby transmitting the laser light through the exhaust gas. The optical path length of the sensor body 50 is crossed through the plurality of exhaust gas passage holes 51, 51... By doing so, the optical path length of the laser light passing through the exhaust gas is secured.

  As described above, the exhaust gas analyzing apparatus 1 according to the present embodiment causes the exhaust gas analyzing sensor 5 to pass a laser beam across the plurality of exhaust gas passage holes 51, 51. Since it is possible to avoid a reduction in measurement accuracy based on breakage of the reflecting mirror and the like while ensuring the optical path length of the laser beam that passes through the exhaust gas without providing it, the component concentration of the exhaust gas can be accurately measured. Moreover, the optical axis shift due to temperature deformation of the sensor body 50 can be reduced, and the component concentration of the exhaust gas can be measured stably even under high temperature conditions. Furthermore, the exhaust gas analysis sensor 5 can be simply configured, and the manufacturing cost and the maintenance cost can be reduced.

  Further, by using the exhaust gas analysis sensor 5 of the present embodiment, it becomes possible to measure the component concentration of the exhaust gas under high temperature conditions. Therefore, the exhaust gas analysis sensor 5 is disposed between the engine 20 and the exhaust manifold 30. Thus, for example, the performance evaluation (fuel consumption and emission) of the engine 20 and the catalyst performance of the catalyst devices 32 and 33 disposed in the exhaust path 3 can be accurately evaluated. In particular, the detailed performance of the engine 20 can be evaluated by attaching the pair of exhaust gas analysis sensors 5 and 5 to positions corresponding to the intake ports and the exhaust ports of the cylinder head 20a.

  Further, in the exhaust gas analysis sensor 5 of the present embodiment, the sensor main body 50 has a light passage hole 52 communicating between the adjacent exhaust gas passage holes 51 and 51 along the optical path of the laser light emitted from the irradiation unit 6. Therefore, by attaching the pair of irradiation unit 6 and light receiving unit 7 to the sensor body 50, it is possible to irradiate the laser beam so as to cross all the exhaust gas passage holes 51, and the sensor structure is simplified. Can be configured.

In particular, in the exhaust gas analyzing apparatus 1 of the present embodiment, in the exhaust gas analyzing sensor 5, a region in the exhaust gas passage hole 51 (exhaust gas region D 1) and a region in the light passage hole 52 (internal region D 2). Therefore, the exhaust gas in the exhaust gas passage hole 51 stays in the internal region D2 as an excess space in the light passage hole 52 or passes between adjacent exhaust gas passage holes 51. It is possible to prevent the exhaust gas from flowing out through the hole 52, and the concentration of the accumulated gas component overlaps with the original measurement result of the concentration of the exhaust gas, or the concentration of the accumulated gas component fluctuates. It is possible to prevent the measurement accuracy from being reduced due to noise.
In particular, when evaluating the performance evaluation of the engine 20 (fuel consumption and emission), it is possible to prevent the exhaust gas from staying in the light passage hole 52 and thereby reduce the performance of the engine 20, and to accurately measure the actual engine. be able to.

  In addition, the structure of the exhaust gas analyzer 1 of a present Example is not limited to the Example mentioned above.

  That is, in the exhaust gas analyzing sensor 5 in the exhaust gas analyzing apparatus 1 of the above-described embodiment, the lens members 90 and 90 are disposed in the light passage hole 52 so as to partition the exhaust gas region D1 and the internal region D2. However, in the exhaust gas analysis sensor 5, a gas supply / discharge path 93 for supplying / discharging inert gas (inert gas) to / from the internal region D2 may be provided in the sensor body 50.

  Specifically, as shown in FIG. 8, the gas supply / discharge path 93 is provided so as to open to the light passage hole 52 of the sensor body 50, and the supply gas for supplying the inert gas to the internal region D <b> 2 in the light passage hole 52. A passage 93 a and a discharge passage 93 b for discharging the inert gas to the outside of the machine are provided in the inner region D <b> 2 in the light transmission hole 52. One end of the supply path 93 a is opened at a position near one lens member 90 provided in the light passage hole 52, and the other end is connected to a gas supply device 94 for inert gas. On the other hand, one end of the discharge path 93 b is opened in the vicinity of the other lens member 90 provided in the light passage hole 52, and the other end is connected to the gas recovery device 95.

  The inert gas sent out from the gas supply device 94 is sent into the light transmission hole 52 through the supply path 93a. The inert gas sent into the light passage hole 52 is eventually discharged from the discharge passage 93 b to the gas recovery device 95 while cooling the lens surfaces of the lens members 90 and 90 of the light passage hole 52. As described above, the gas supply / discharge path 93 is provided in the sensor main body 50 of the exhaust gas analysis sensor 5, so that the inert gas is supplied from the gas supply device 94 → the supply path 93a → the light transmission hole 52 (internal region D2) → the discharge path 93b. → Sent to gas recovery device 95.

  As described above, the sensor 5 for exhaust gas analysis of the present embodiment is provided with the gas supply / discharge passage 93 for supplying and discharging the inert gas in the region (inner region D2) in the light passage hole 52 in the sensor body 50. The accumulated gas in the light transmission hole 52 can be discharged outside the apparatus, and the concentration of the accumulated gas overlaps with the original measurement result of the exhaust gas concentration, or the concentration of the accumulated gas component fluctuates. The measurement accuracy of the exhaust gas can be improved by noise generated at the time.

  However, the gas supply / discharge path 93 does not need to be provided so that the inert gas can be supplied to and discharged from all the light transmission holes 52 provided in the sensor body 50. For example, the inert gas is supplied to and discharged from only some of the light transmission holes 52. May be provided. In particular, a gas supply / exhaust path 93 is provided in the sensor body 50 so that the inert gas can be supplied / exhausted to the separation of the adjacent exhaust gas passage holes 51, that is, the light passage holes 52 having a large length or diameter. Preferably it is configured.

  Further, the lens member 90 and the gas supply / discharge path 93 provided in the light passage hole 52 may not necessarily be provided according to the length and diameter of the light passage hole 52.

  Further, in the sensor main body 50, a heater for preventing condensation on the lens surfaces of the lens members 55 and 90 in the vicinity of the arrangement of the lens member 55 provided in the light passage hole 53 and the lens member 90 provided in the light passage hole 52. Etc. may be provided.

As described above, the internal combustion engine that can be measured using the exhaust gas analyzer 1 of the present embodiment is not limited to the configuration of the four-cylinder engine 20, but also, for example, a three-cylinder engine or a V-type six-cylinder engine. In such a case, the exhaust gas analyzing sensor 5 is provided with three exhaust gas passage holes 51, 51,.
As described above, the exhaust gas passage holes 51 can be appropriately provided in the sensor body 50 at the number and position corresponding to the number of cylinders of the engine 20 (or the exhaust holes 20b of the cylinder head 20a).

  Further, the exhaust gas analyzing apparatus 1 of the present embodiment is the same as the case where the exhaust gas analyzing sensor 5 is attached between the cylinder head 20a of the engine 20 and the intake manifold and the component concentration in the exhaust gas is measured as described above. In addition, it can be used as an intake gas analyzer for measuring intake gas. Specifically, the exhaust gas analyzer 1 is attached to an intake passage that supplies intake gas to the internal combustion engine (engine 20), and includes an air intake gas analyzer that includes a sensor unit that measures the component concentration of the intake gas in the intake passage. As a device, a sensor unit includes a sensor body in which a plurality of intake gas passage holes through which intake gas from an internal combustion engine passes are formed along a predetermined direction, and a laser beam toward a direction crossing each intake gas passage hole. It is possible to provide an irradiating unit that irradiates and a light receiving unit that receives the laser light emitted from the irradiating unit.

The side view which showed the whole structure of the exhaust gas analyzer which concerns on one Example of this invention. The perspective view which showed the structure of the sensor for exhaust gas analysis of a present Example. The perspective view which showed the attachment state of the sensor for exhaust gas analysis of a present Example. The front sectional view of the sensor for exhaust gas analysis of this example. The expanded sectional view which showed the attachment structure of the irradiation part. The expanded sectional view which showed the attachment structure of the light-receiving part. Sectional drawing which expanded and showed the light transmission hole vicinity. Sectional drawing which expanded and showed the light transmission hole vicinity of the sensor for exhaust gas analysis of another Example.

DESCRIPTION OF SYMBOLS 1 Exhaust gas analyzer 3 Exhaust path 5 Exhaust gas analysis sensor (sensor part)
6 Irradiation unit 7 Light receiving unit 20 Engine (internal combustion engine)
50 Sensor body 51 Exhaust gas passage hole 52 Light passage hole

Claims (4)

In an exhaust gas analyzer equipped with a sensor unit that is attached to an exhaust path for exhausting exhaust gas from an internal combustion engine and measures the component concentration of the exhaust gas in the exhaust path,
The sensor unit is
A sensor body in which a plurality of exhaust gas passage holes through which exhaust gas from the internal combustion engine passes are formed along a predetermined direction;
An irradiation unit for irradiating a laser beam in a direction crossing the plurality of exhaust gas passage holes;
An exhaust gas analyzer, comprising: a light receiving unit that receives the laser beam emitted from the irradiation unit.   2. The exhaust gas analysis according to claim 1, wherein the sensor main body is provided with a light passage hole that communicates between the adjacent exhaust gas passage holes along an optical path of laser light emitted from the irradiation unit. apparatus.   3. The sensor body according to claim 2, wherein a lens member for transmitting laser light is provided in the light passage hole so as to partition a region in the exhaust gas passage hole and a region in the light passage hole. Exhaust gas analyzer.   The exhaust gas analyzer according to claim 2 or 3, wherein the sensor main body is provided with a gas supply / discharge path for supplying / discharging inert gas in a region within the light passage hole.

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