JP2015222218A - Particulate matter detection apparatus and particulate matter detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a particulate matter detection apparatus configured to quickly and accurately detect the amount of particulate matters accumulated, and a particulate matter detection method.SOLUTION: A particulate matter detection apparatus 1 includes particle amount detection means 2, a control unit 4, and heating means 3. The particle amount detection means 2 includes: an accumulation section where particulate matters are accumulated; and a pair of counter electrodes arranged on the accumulation section. The particle amount detection means 2 changes output of an electric signal, according to the change in electrical characteristics when the particulate matters are accumulated on the accumulation section. The control unit 4 determines the amount of particulate matters accumulated on the accumulation section, on the basis of the electric signal. The heating means 3 heats the particulate matters accumulated on the accumulation section. The particulate matter detection apparatus 1 detects the amount of particulate matters accumulated on the accumulation section and heated by the heating means 3 at 100-600°C.

Description

  The present invention relates to a particulate matter detection device for detecting the amount of particulate matter contained in exhaust gas generated from an internal combustion engine, and a particulate matter detection method using the particulate matter detection device.

  An exhaust gas purification apparatus that collects particulate matter (PM) contained in the exhaust gas is provided in an exhaust pipe of the internal combustion engine. The exhaust gas purification apparatus includes a particulate matter detection device having a PM sensor that detects the amount of particulate matter contained in the exhaust gas, and the exhaust gas purification device is based on information obtained by the particulate matter detection device. Failure detection has been performed.

  Examples of the particulate matter detection device used in the exhaust gas purification device include the particulate matter detection devices disclosed in Patent Document 1 and Patent Document 2. The particulate matter detection device of Patent Document 1 includes a pair of counter electrodes, and the capacitance is changed by depositing particulate matter on a PM sensor for detecting the concentration of the particulate matter. It is intended to detect the amount of particulate matter contained in exhaust gas.

  The particulate matter detection device of Patent Document 2 utilizes the fact that soot contained in the particulate matter has electrical conductivity, and is composed of a porous conductive material that captures soot. The detection electrode and at least a pair of counter electrodes disposed on the detection electrode and measuring the electric resistance of the detection electrode.

JP 2011-87991 A JP 2006-266961 A

However, the particulate matter detection devices disclosed in Patent Document 1 and Patent Document 2 have the following problems.
In the particulate matter detection devices of Patent Literature 1 and Patent Literature 2, the PM sensor is disposed in the exhaust pipe through which the exhaust gas flows, and the particulate matter is deposited on the PM sensor to detect the amount of particulate matter deposited. ing. The PM sensor is configured to change the output by changing the electrical characteristics between the pair of counter electrodes due to the particulate matter deposited so as to connect the pair of counter electrodes. At this time, if the amount of particulate matter deposited on the PM sensor is small, even if the particulate matter is deposited so as to connect the pair of counter electrodes, the amount of change in electrical characteristics becomes small, and the PM sensor Changes in output are unlikely to occur.

Further, the particulate matter that is scattered on the PM sensor apart from the pair of counter electrodes and is not electrically connected to the counter electrode does not contribute to the change in the electrical characteristics between the pair of counter electrodes and is not detected. For this reason, it is not possible to detect an accurate deposition amount until sufficient particulate matter is deposited on the PM sensor.
Further, the particulate matter includes a low-conductivity particulate matter having a large electric resistance value. Since this low-conductivity particulate matter has lower conductivity than a normal particulate matter, even if it is deposited on the PM sensor, it is not accurately detected as the amount of particulate matter deposited.

  The present invention has been made in view of such a background, and shows a particulate matter detection device capable of quickly and accurately detecting the amount of particulate matter deposited and a particulate matter detection method using the particulate matter detection device. It is.

One embodiment of the present invention includes a deposition portion that deposits a part of particulate matter contained in exhaust gas discharged from an internal combustion engine, and a pair of counter electrodes that are spaced apart from each other on the deposition portion. Particle amount detecting means for changing the output of an electrical signal in accordance with a change in electrical characteristics due to the particulate matter being deposited on the deposition portion;
A control unit for determining a deposition amount of the particulate matter in the deposition target portion based on the electrical signal output by the particle amount detection means;
Heating means for heating the particulate matter deposited on the deposition portion,
The particulate matter detection apparatus, wherein the particulate matter deposited on the deposition portion is heated to 100 ° C. to 600 ° C. by the heating means to detect the amount of the particulate matter deposited. It is in.

According to another aspect of the present invention, there is provided a depositing portion for depositing a part of particulate matter contained in exhaust gas discharged from an internal combustion engine, and a pair of counter electrodes disposed apart from each other on the depositing portion. And a particle amount detecting means for outputting an electrical signal in accordance with a change in electrical characteristics due to the particulate matter being deposited on the deposition target part,
A control unit for determining a deposition amount of the particulate matter deposited on the deposition portion based on the electrical signal output by the particle amount detection means;
A method for detecting the amount of the particulate matter deposited on the deposition portion using a particulate matter detection device comprising a heating means for heating the particulate matter deposited on the deposition portion. There,
Depositing the particulate matter on the portion to be deposited of the particle amount detecting means;
In the state where the particulate matter deposited on the deposition portion is heated to 100 ° C. to 600 ° C. by the heating means, an electric signal corresponding to a change in electric resistance value between the pair of counter electrodes is sent to the particle amount detection means. Output by
In the particulate matter detection method, the amount of the particulate matter deposited on the deposition portion is detected based on the electrical signal.

  The particulate matter detection device includes the heating unit, and the particulate matter deposited on the deposition target portion is heated to 100 ° C. to 600 ° C. by the heating unit. The accumulation amount is detected. As a result, it is possible to accurately detect the amount of deposition deposited on the portion to be deposited.

  That is, the particulate matter has characteristics that when heated, the crystallinity of carbon contained in the particulate matter is improved and the electrical resistance is lowered. Therefore, by heating the particulate matter deposited on the portion to be deposited and reducing the electrical resistance of the particulate matter, the pair of opposing surfaces can be used even when the amount of particulate matter deposited is small. The amount of change in electrical characteristics between the electrodes can be increased.

  In particular, during the initial start of the internal combustion engine or during low-load operation, a low-conductivity particulate material having a small particle size and low crystallinity is contained. Since this low-conductivity particulate matter has higher electrical resistance and lower conductivity than other particulate matter, even if it is deposited on the deposited portion, it does not easily affect the electrical characteristics between the pair of counter electrodes. . In the particulate matter detection device, the electrical resistance of the low-conductivity particulate matter can be reduced by heating the low-conductivity particulate matter by the heating means. Therefore, the low conductive particulate matter can contribute to a change in electrical characteristics between the pair of counter electrodes. As a result, more particulate matter is deposited on the portion to be deposited, which can contribute to a change in electrical characteristics between the pair of counter electrodes. Therefore, it is possible to detect the accumulation amount quickly and accurately even at the initial start of the internal combustion engine or during low load operation, which has been difficult to detect.

  In addition, by heating the particulate matter deposited on the portion to be deposited, moisture and volatile components attached together with the particulate matter can be evaporated. Therefore, it is possible to prevent the electrical characteristics between the pair of counter electrodes from being affected by moisture and volatile components. Therefore, the detection accuracy of the accumulation amount can be further increased.

  In the particulate matter detection method, as described above, in the state where the particulate matter deposited on the deposition target portion is heated to 100 ° C. to 600 ° C. by the heating means, the electrical resistance value between the pair of counter electrodes is measured. The electric signal corresponding to the change is output by the particle amount detecting means. Therefore, it is possible to detect the accumulation amount of the particulate matter quickly and accurately.

  As described above, according to the particulate matter detection device and the particulate matter detection method, the amount of particulate matter deposited can be detected quickly and accurately.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 3 is an explanatory diagram showing particle amount detection means in the first embodiment. FIG. 3 is an explanatory diagram showing the particulate matter before heating in Example 1. FIG. 3 is an explanatory diagram showing the particulate matter after heating in Example 1. The graph which shows the relationship between the magnitude | size of the output of an electrical signal in Example 1, and collection time. The graph which shows the relationship between the magnitude | size of the output of an electric potential signal, and the collection time in a confirmation example.

  In the particle amount detection unit and the particle amount detection method, it is preferable that the particle amount detection unit changes the output of the electric signal according to a change in electric resistance between the pair of counter electrodes. The electric resistance type particle amount detection means utilizing the change in electric resistance value between the pair of counter electrodes has higher detection accuracy of the particulate matter and less variation than other types of particle amount detection means. . Therefore, it is possible to further improve the detection accuracy of the accumulation amount of the particulate matter.

  Further, in the state where the particulate matter is heated by the heating means, the amount of particulate matter deposited on the deposition target portion is controlled by the control unit based on the maximum value of the electrical signal output by the particle amount detection means. It is preferable to determine. When the particulate matter is heated, the electric resistance decreases, but if the heating is continued, the electric resistance increases again. Therefore, the detection accuracy of the particulate matter is further improved by determining the amount of the particulate matter deposited in the state where the electrical resistance of the particulate matter is the lowest, that is, the state where the electrical signal is maximized. be able to.

  Moreover, the heating temperature in the said heating means is set to 100 to 600 degreeC. When the heating temperature by the heating means is less than 100 ° C., it takes time to evaporate moisture and volatile components, and moisture and volatile components may remain. Further, when the heating temperature by the heating means exceeds 600 ° C., the particulate matter starts to burn, and thus the amount of the deposited particulate matter cannot be accurately detected.

Example 1
Examples of the particulate matter detection device will be described with reference to FIGS.
As shown in FIGS. 1 and 2, the particulate matter detection device 1 includes a particle amount detection unit 2, a control unit 4, and a heating unit 3. The particle amount detection means 2 is disposed on the deposition portion 211 and the deposition portion 211 for depositing a part of the particulate matter 6 (FIG. 3) contained in the exhaust gas discharged from the internal combustion engine 5. A pair of counter electrodes 22 is provided. The particle amount detection means 2 changes the output of the electrical signal in accordance with the change in electrical characteristics caused by the particulate matter 6 being deposited on the deposition target portion 211. The control unit 4 determines the deposition amount of the particulate matter 6 in the deposition target portion 211 based on the electrical signal output by the particle amount detection means 2. The heating means 3 heats the particulate matter 6 deposited on the portion 211 to be deposited.
The particulate matter detection device 1 detects the deposition amount of the particulate matter 6 in a state where the particulate matter 6 deposited on the deposition target portion 211 is heated to 100 ° C. to 600 ° C. by the heating unit 3.

This will be described in more detail below.
As shown in FIG. 1, the particulate matter detection device 1 is for detecting particulate matter 6 contained in exhaust gas discharged through an exhaust pipe 52 from an internal combustion engine 5 mounted on an automobile. The internal combustion engine 5 of this example is a diesel engine equipped with a supercharger 51. Further, the exhaust pipe 52 connected to the internal combustion engine 5 is provided with a purification system 55 including an oxidation catalyst 53 (DOC) and a particulate filter 54 (DPF).

  The particulate matter detection device 1 includes a particulate amount detection unit 2 that detects the amount of particulate matter 6 contained in the exhaust gas, and a control unit 4 that receives an electrical signal output from the particulate amount detection unit 2. .

  As shown in FIGS. 1 and 2, the particle amount detection means 2 is provided on the downstream side of the purification system 55 in the exhaust pipe 52. The particle amount detection unit 2 is a PM sensor that detects the amount of the particulate matter 6, and includes a collection unit 21 that collects a part of the particulate matter 6 and a heating unit 3 that heats the collection unit 21. I have.

  As shown in FIG. 2, the collection unit 21 includes a deposition part 211 that deposits the particulate matter 6 in the exhaust gas, and a pair of counter electrodes 22 that are disposed apart from each other on the deposition part 211. . The deposited portion 211 has a substantially rectangular plate shape and is formed of an insulating material. The pair of counter electrodes 22 is made of a conductive material, and is formed on the surface of the portion to be deposited 211. Each of the pair of counter electrodes 22 includes an electrode base portion 221 formed in parallel to the longitudinal direction of the deposition target portion 211 and a plurality of comb teeth portions 222 extending from the electrode base portion 221 perpendicular to the longitudinal direction. ing. Each counter electrode 22 is arranged so that the electrode bases 221 face each other, and is arranged so that the comb teeth 222 in the other counter electrode 22 enter between the comb teeth 222 in one counter electrode 22. Yes.

  The particulate matter 6 is deposited on the portion 211 to be deposited and the pair of counter electrodes 22 are electrically connected to each other by the particulate matter 6, whereby the electrical resistance value between the pair of counter electrodes 22 is reduced. A voltage is applied between the pair of counter electrodes 22, and the amount of current as an electric signal flowing between the counter electrodes 22 changes with a change in the electrical resistance value between the pair of counter electrodes 22. Thereby, the current value output from the particle amount detection means 2 to the control unit 4 changes. That is, the current value output from the particle amount detection means 2 changes according to the amount of particulate matter 6 deposited in the deposition target 211 and has information on the amount of particulate matter 6 deposited. . The control unit 4 includes a shunt resistor, and outputs a voltage calculated by the product of the output current value and the shunt resistor to the ECU 7 (engine control unit).

  As shown in FIG. 2, the heating means 3 has a heat wire 31 that generates heat by passing a current supplied from a power source 33, and a heating base portion 32 made of an insulating material provided with the heat wire 31. . The heating means 3 is disposed so as to be stacked with the deposition target portion 211 on the side opposite to the side where the pair of counter electrodes 22 is disposed in the deposition target portion 211. Preliminary heating for removing moisture and volatile components collected in the collection unit 21 together with the particulate matter 6 and high-temperature heating for removing the particulate matter 6 collected in the collection unit 21 are performed. It is configured as follows.

  The temperature of preheating can be set to 100 degreeC-600 degreeC. In this example, the preheating temperature was 400 ° C. The preheating is performed from when the particulate matter 6 is deposited on the deposition target 211 and before the detection is completed until the particulate amount detection unit 2 detects the amount of the particulate matter 6 deposited. Further, when the preheating temperature is set to 400 ° C. to 600 ° C., the crystallinity of carbon contained in the particulate matter 6 can be improved efficiently.

  The temperature of the high temperature heating is set to 800 ° C. The high temperature heating is newly performed after detecting the amount of the particulate matter 6 deposited or when the operation of the internal combustion engine 5 is stopped because the particulate matter 6 is not sufficiently deposited on the deposition target 211. It is performed at a timing before depositing.

The control unit 4 of this example controls the heating by the heating means 3 and the amount of the particulate matter 6 deposited in the deposition target part 211 based on the output of the electrical signal and the particulate matter 6 discharged during the collection time. The total amount of emissions is calculated.
In this example, the control of the heating means 3 by the control unit 4 is performed based on the voltage calculated from the output of the electric signal. When the calculated voltage reaches a predetermined target voltage V (FIG. 5), the control unit 4 heats the particulate matter 6 to the preheating temperature by the heating means 3.

  The control unit 4 includes the deposition amount relationship data indicating the relationship between the output of the electrical signal and the deposition amount of the particulate matter 6 in the deposition target 211, and the deposition amount of the particulate matter 6 in the deposition subject 211 and the exhaust gas. The emission amount relation data showing the relationship with the total emission amount of the particulate matter 6 to be stored is stored. The accumulation amount-related data and the emission amount-related data are obtained in advance by performing a confirmation test in the internal combustion engine 5. The control unit 4 calculates the deposition amount of the particulate matter 6 using the deposition amount related data based on the output of the electrical signal. Then, the total discharge amount of the particulate matter 6 can be calculated using the discharge amount relation data based on the calculated deposition amount. As a result, the calculated total discharge amount of the particulate matter 6 is output to the control unit 4.

Next, an example of the particulate matter detection method using the particulate matter detection device 1 will be described.
FIG. 5 shows an output of an electrical signal in which the vertical axis represents the voltage calculated from the electrical signal output from the particle amount detection means 2 and the horizontal axis represents the collection time during which the particulate matter 6 was collected by the particle amount detection means 2. It is a graph which shows the relationship between and collection time. As shown by the solid line L1, after the collection of the particulate matter 6 is started, there is no change in the output of the electric signal for a while, but the particulate matter in the deposited portion 211 as the collection time elapses. The amount of material deposition increases. When the collection time exceeds S1, the output of the electric signal gradually increases. As shown in FIG. 3, when the output of the electric signal reaches the target voltage V, a part of the particulate matter 6 is deposited on the deposition target portion 211 so as to connect the pair of counter electrodes 22. Part of the particulate matter 6 is a low-conductivity particulate matter 61 having low crystallinity and high electrical resistance. The low-conductivity particulate matter 61 has a high electric resistance and has a small influence on the electric resistance between the pair of counter electrodes 22. Further, the particulate matter 6 that is not electrically connected to the pair of counter electrodes 22 exists around the particulate matter 6 deposited so as to connect the pair of counter electrodes 22.

  When the output of the electric signal reaches the target voltage V, the control unit 4 activates the heating means 3. As shown in FIG. 4, when the particulate matter 6 is heated by the heating means 3, the crystallinity of carbon contained in the particulate matter 6 is improved, and the electrical resistance of the particulate matter 6 is lowered. Thereby, the electrical resistance of the low-conductivity particulate matter 61 is also reduced, and can contribute to the electrical resistance between the pair of counter electrodes 22, similarly to the other particulate matter 6.

  In this way, by reducing the resistance value of the particulate matter 6 and increasing the number of the particulate matter 6 that contributes to the electrical resistance between the pair of counter electrodes 22, it is output from the particle amount detection means 2. The electrical signal increases. In addition, if the heating state by the heating means 3 is maintained, the output of the electric signal will decrease due to the influence of thermophoresis. In this example, the accumulation amount of the particulate matter 6 in the deposition target portion 211 by the control unit 4 based on the electrical signal when the voltage output in the state where the particulate matter 6 is heated reaches the maximum value Vm. Determine.

Next, the function and effect of this example will be described.
The particulate matter detection device 1 includes a heating unit 3, and the particulate matter 6 deposited on the deposition target portion 211 is heated to 100 ° C. to 600 ° C. by the heating unit 3. The accumulation amount is detected. Thereby, the deposition amount deposited on the deposition target portion 211 can be detected with high accuracy.

  That is, the particulate matter 6 has characteristics that when heated, the crystallinity of carbon contained in the particulate matter 6 is improved and the electrical resistance is lowered. Therefore, even if the amount of particulate matter 6 deposited is small by heating the particulate matter 6 deposited on the deposition target 211 and reducing the electrical resistance of the particulate matter 6, a pair of counter electrodes The amount of change in electrical characteristics between the two can be increased.

  In particular, during the initial start of the internal combustion engine 5 or during low-load operation, the low-conductivity particulate matter 61 having a small particle size and low crystallinity is included. Since this low-conductivity particulate matter 61 has a higher electrical resistance and lower conductivity than the other particulate matter 6, even if it is deposited on the deposition target 211, the electrical characteristics between the pair of counter electrodes 22 are affected. Hard to give. In the particulate matter detection device 1, the electrical resistance of the low conductive particulate matter 61 can be lowered by heating the low conductive particulate matter 61 by the heating means 3. Therefore, the low conductive particulate matter 61 can contribute to the change in electrical characteristics between the pair of counter electrodes 22. As a result, more particulate matter 6 is deposited on the portion 211 to be deposited, which can contribute to the electrical characteristics between the pair of counter electrodes 22. Therefore, it is possible to detect the accumulation amount quickly and accurately even at the initial start of the internal combustion engine 5 or during the low load operation, which has been difficult to detect.

  In addition, by heating the particulate matter 6 deposited on the portion 211 to be deposited, moisture and volatile components attached together with the particulate matter 6 can be evaporated. Thereby, it can prevent that the electrical property between a pair of counter electrodes 22 is influenced by a water | moisture content or a volatile component. Therefore, the detection accuracy of the accumulation amount can be further increased.

  Further, as described above, in the particulate matter detection method, the electrical resistance value between the pair of counter electrodes 22 in a state where the particulate matter 6 deposited on the deposition target 211 is heated to 100 ° C. to 600 ° C. by the heating unit 3. The particle amount detecting means 2 outputs an electrical signal corresponding to the change in the above. Therefore, the amount of deposition can be detected quickly and accurately.

  Further, the particle amount detection means 2 changes the output of the electric signal according to the change in the electric resistance between the pair of counter electrodes 22. The electric resistance type particle amount detection means 2 that utilizes the change in the electric resistance value between the pair of counter electrodes 22 has a higher accuracy in detecting the particulate matter 6 than the other types of particle amount detection means 2, and there is variation. Few. Therefore, the detection accuracy of the particulate matter 6 can be further improved.

  Further, in the state where the particulate matter 6 is heated by the heating means 3, the amount of particulate matter 6 deposited on the deposition target portion 211 by the control unit 4 based on the maximum value of the electrical signal output from the particle amount detection means 2. Determine. When the particulate matter 6 is heated, if the decrease in electric resistance exceeds the peak, thermophoresis occurs, and the electric resistance increases again. Therefore, it is possible to further improve the detection accuracy of the particulate matter 6 by determining the amount of the particulate matter 6 deposited in a state where the electrical resistance of the particulate matter 6 is the lowest, that is, in a state where the electrical signal is maximized. Can do.

  Further, the control unit 4 has deposition amount relationship data indicating the relationship between the electrical signal output by the particle amount detection means 2 and the deposition amount of the particulate matter 6 deposited on the deposition target portion 211. The deposition amount is calculated from the electrical signal using the deposition amount relationship data. Therefore, the deposition amount can be easily calculated from the electrical signal.

  Further, the control unit 4 has emission amount relation data indicating the relationship between the accumulation amount of the particulate matter 6 deposited on the deposition target portion 211 and the total emission amount of the particulate matter 6 contained in the exhaust gas. The total emission amount is calculated from the accumulation amount using the emission amount relation data. Therefore, the total discharge amount of the particulate matter 6 in the internal combustion engine 5 can be calculated from the accumulated amount of the particulate matter 6. As a result, the internal combustion engine 5 and the purification system 55 that removes the particulate matter 6 contained in the exhaust gas can be controlled more precisely, and the environmental load due to the discharge of the particulate matter 6 can be reduced.

  Further, the heating means 3 also serves as a heater for removing the particulate matter 6 deposited on the portion 211 to be deposited. Therefore, the particulate matter 6 can be heated and removed by the heater. Thereby, the structure of the particulate matter detection device 1 can be simplified.

  As described above, according to the particulate matter detection device 1 and the particulate matter detection method, the deposition amount of the particulate matter 6 can be detected quickly and accurately.

(Confirmation test)
In this confirmation test, the relationship between the voltage output from the particle amount detection means 2 in the particulate matter detection device 1 and the deposition time of the particulate matter 6 was confirmed using Examples and Comparative Examples.
The comparative example is the particulate matter detection device 1 when the particulate matter 6 is not heated by the heating means 3. In addition, it is the same as that of the particulate matter detection apparatus 1 of the said Example 1 except not heating by the heating means 3. FIG.
The embodiment is the particulate matter detection device 1 shown in the first embodiment.

  In FIG. 6, the vertical axis represents the voltage output from the particle amount detection means 2, and the horizontal axis represents the deposition time during which the particulate matter 6 is deposited in the deposition target portion 211. Deposition times were 50 seconds, 100 seconds, 150 seconds, 200 seconds, 300 seconds and 400 seconds. Points A1 to A6 indicate output voltages calculated from the electrical signals output during each deposition time of the example. Points B1 to B6 indicate output voltages calculated from electrical signals output during each deposition time of the comparative example. The operating conditions such as the rotational speed of the internal combustion engine 5 are constant.

As shown in B1 to B3 of FIG. 6, in the comparative example, the output voltage is not detected when the deposition time is between 50 seconds and 150 seconds. Further, the output voltage is detected when the deposition time is between 200 seconds and 400 seconds, and the output voltage increases as time elapses.
As shown in FIGS. A1 to A6 of FIG. 6, in the embodiment, the output voltage is detected when the deposition time is 50 seconds. The output voltage increases as the deposition time elapses. In any of the deposition times, the output voltage of the example is larger than the output voltage of the comparative example.
Thus, according to the particulate matter detection device 1 shown in Example 1, the amount of particulate matter 6 deposited can be detected quickly and accurately compared to the comparative example.

DESCRIPTION OF SYMBOLS 1 Particulate matter detection apparatus 2 Particle amount detection means 211 Deposited part 22 Counter electrode 3 Heating means 4 Control unit 5 Internal combustion engine 6 Particulate matter

Claims (12)

A depositing part (211) for depositing a part of the particulate matter (6) contained in the exhaust gas discharged from the internal combustion engine (5), and a pair of parts disposed apart from each other on the depositing part (211) And a counter electrode (22), and a particle amount detecting means for changing an output of an electric signal in accordance with a change in electrical characteristics caused by deposition of the particulate matter (6) on the deposition target (211). (2) and
A control unit (4) for determining a deposition amount of the particulate matter (6) in the deposition target part (211) based on the electric signal output by the particle amount detection means (2);
Heating means (3) for heating the particulate matter (6) deposited on the deposition part (211),
With the heating means (3), the particulate matter (6) deposited on the deposition portion (211) is heated to 100 ° C. to 600 ° C., and the amount of the particulate matter (6) deposited is reduced. A particulate matter detection device (1) characterized by detecting.   The particulate matter detection unit according to claim 1, wherein the particle amount detection means (2) changes the output of the electrical signal in accordance with a change in electrical resistance between the pair of counter electrodes (22). Device (1).   In the state where the particulate matter (6) is heated by the heating means (3), the control unit (4) is used to control the object to be covered based on the maximum value of the electric signal output from the particle amount detection means (2). The particulate matter detection device (1) according to claim 1 or 2, wherein the amount of the particulate matter (6) deposited in the deposition part (211) is determined.   The control unit (4) showed the relationship between the electrical signal output by the particle amount detection means (2) and the deposition amount of the particulate matter (6) deposited on the deposition target part (211). The particulate matter according to any one of claims 1 to 3, wherein the particulate matter has deposit amount relation data, and the deposit amount is calculated from an electrical signal using the deposit amount relation data. Detection device (1).   The control unit (4) showed the relationship between the amount of the particulate matter (6) deposited on the deposition target part (211) and the total amount of the particulate matter (6) contained in the exhaust gas. The particle according to any one of claims 1 to 4, further comprising emission-related data, wherein the total emission is calculated from the accumulation amount using the emission-related data. A state substance detection device (1).   The said heating means (3) serves as the heater for removing the said particulate matter (6) deposited on the said deposition part (211), The any one of Claims 1-5 characterized by the above-mentioned. The particulate matter detection device according to (1). A depositing part (211) for depositing a part of the particulate matter (6) contained in the exhaust gas discharged from the internal combustion engine (5), and a pair of parts disposed apart from each other on the depositing part (211) And a counter electrode (22), and a particle amount detection means (2) that outputs an electrical signal in accordance with a change in electrical characteristics caused by the particulate matter (6) being deposited on the deposition target portion (211). )When,
A control unit (4) for determining a deposition amount of the particulate matter (6) deposited on the deposition target portion (211) based on an electrical signal output by the particle amount detection means (2);
Using the particulate matter detection device (1) provided with a heating means (3) for heating the particulate matter (6) deposited on the deposition portion (211), the deposition portion (211) A method of detecting the amount of the particulate matter (6) deposited on the substrate,
The particulate matter (6) is deposited on the deposition portion (211) of the particle amount detection means (2),
Change in electrical resistance value between the pair of counter electrodes (22) in a state where the particulate matter (6) deposited on the deposition target part (211) is heated to 100 ° C. to 600 ° C. by the heating means (3). An electric signal corresponding to the above is output by the particle amount detection means (2),
A particulate matter detection method, comprising: detecting an accumulation amount of the particulate matter (6) deposited on the deposition target part (211) based on the electrical signal.   The particulate matter detection unit according to claim 7, wherein the particle amount detection means (2) changes the output of the electrical signal in accordance with a change in electrical resistance between the pair of counter electrodes (22). Method.   In the state where the particulate matter (6) is heated by the heating means (3), the control unit (4) is used to control the object to be covered based on the maximum value of the electric signal output from the particle amount detection means (2). The particulate matter detection method according to claim 7 or 8, wherein the amount of the particulate matter (6) deposited in the deposition part (211) is determined.   The control unit (4) determines the relationship between the electrical signal output by the particle amount detection means (2) and the deposition amount of the particulate matter (6) deposited on the deposition target part (211). Particles according to any one of claims 7 to 9, characterized in that the accumulation amount-related data shown is included, and the accumulation amount is calculated from an electrical signal using the accumulation amount-related data. Method for detecting particulate matter.   The control unit (4) showed the relationship between the amount of the particulate matter (6) deposited on the deposition target part (211) and the total amount of the particulate matter (6) contained in the exhaust gas. The particle according to any one of claims 7 to 10, further comprising emission-related data, wherein the total emission is calculated from the accumulation amount using the emission-related data. Method for detecting particulate matter.   The heater for removing the said particulate matter (6) deposited on the said to-be-deposited part (211) is used as said heating means (3), It is any one of Claims 7-11 characterized by the above-mentioned. Particulate matter detection method.

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