WO2016117577A1 - Capteur - Google Patents

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Publication number
WO2016117577A1
WO2016117577A1 PCT/JP2016/051481 JP2016051481W WO2016117577A1 WO 2016117577 A1 WO2016117577 A1 WO 2016117577A1 JP 2016051481 W JP2016051481 W JP 2016051481W WO 2016117577 A1 WO2016117577 A1 WO 2016117577A1
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Prior art keywords
filter
amount
sensor
filter member
particulate matter
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Application number
PCT/JP2016/051481
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English (en)
Japanese (ja)
Inventor
正 内山
Original Assignee
いすゞ自動車株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2016004641A external-priority patent/JP6766358B2/ja
Application filed by いすゞ自動車株式会社 filed Critical いすゞ自動車株式会社
Priority to CN201680006239.7A priority Critical patent/CN107209099A/zh
Priority to EP16740184.3A priority patent/EP3252453B1/fr
Priority to US15/545,213 priority patent/US10481061B2/en
Publication of WO2016117577A1 publication Critical patent/WO2016117577A1/fr

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
    • G01N15/02—Investigating particle size or size distribution

Definitions

  • the present invention relates to a sensor, and more particularly, to a PM sensor that detects the total amount of particulate matter (hereinafter referred to as PM) contained in exhaust gas.
  • PM particulate matter
  • a sensor that detects the particle size distribution and emission amount of PM contained in exhaust gas discharged from an internal combustion engine is known.
  • solids when filters having different porosity are provided in order of increasing porosity in order from the upstream side in the flow direction of the exhaust gas to partition the chamber and burn PM for each particle size collected in the chamber A sensor that detects the particle size distribution and emission amount of PM based on an electromotive force generated in an electrolyte layer has been proposed (see, for example, Patent Document 1).
  • This invention is made
  • the objective is to provide the sensor which can estimate continuously PM quantity for every particle size of PM contained in exhaust gas. . It can also be installed in automobiles.
  • the sensor of the present disclosure is a collection unit in which a plurality of filter members that collect particulate matter in exhaust gas and having different porosity from each other are arranged in descending order of the porosity from upstream to downstream of the exhaust gas; Based on a pair of electrodes opposed to each of the plurality of filter members and the capacitance change amount between the pair of electrodes, each of the filter members having different porosity is captured. Estimating means for estimating the amount of collected particulate matter for each filter member.
  • the senor of the present disclosure is a collection unit in which a plurality of filter members having different average pore diameters for collecting particulate matter in exhaust gas are arranged in order of increasing average pore diameter from upstream to downstream of the exhaust gas. And a pair of electrodes arranged opposite to each other with the filter member sandwiched between each of the plurality of filter members, and each of the filter members having different average pore diameters based on the amount of change in capacitance between the pair of electrodes. Estimating means for estimating the amount of particulate matter collected in each filter member.
  • the sensor of the present disclosure is a collection in which a plurality of filter members having different physical property values for collecting particulate matter in exhaust gas are arranged in descending order of the physical property values from upstream to downstream of the exhaust gas.
  • the sensor of the present disclosure it is possible to continuously estimate the amount of PM for each particle size of PM contained in the exhaust gas.
  • FIG. 1 is a schematic configuration diagram illustrating an example of an exhaust system to which the PM sensor according to the first embodiment is applied.
  • FIG. 2 is a schematic partial cross-sectional view showing the PM sensor of the first embodiment.
  • FIG. 3 is a partially enlarged cross-sectional view showing the main part of the PM sensor of the first embodiment.
  • FIG. 4 is a timing chart illustrating filter regeneration, filter temperature change, and PM amount integration according to the first embodiment.
  • FIG. 5 is a schematic partial cross-sectional view showing the PM sensor of the second embodiment.
  • FIG. 6 is a schematic perspective view of a PM sensor according to the third embodiment.
  • 7A is a schematic perspective view of each sensor unit according to the third embodiment
  • FIG. 7B is a schematic exploded perspective view of each sensor unit according to the third embodiment.
  • FIG. 8 is a schematic cross-sectional view of a PM sensor according to the fourth embodiment.
  • FIG. 9 is a schematic configuration diagram illustrating an example of an exhaust system to which a PM sensor according to another
  • FIG. 1 is a schematic configuration diagram illustrating an example of an exhaust system of a diesel engine (hereinafter simply referred to as an engine) 100 to which the sensor 10A of the first embodiment is applied.
  • an oxidation catalyst 210, a DPF 220, and a NOx purification catalyst 230 are provided in this order from the exhaust upstream side.
  • the sensor 10 ⁇ / b> A of the present embodiment is preferably provided in the exhaust pipe 110 on the downstream side of the DPF 220.
  • the sensor 10A may be provided in the exhaust pipe 110 upstream of the oxidation catalyst 210.
  • the sensor 10A includes a case member 11 inserted into the exhaust pipe 110, a pedestal portion 20 for attaching the case member 11 to the exhaust pipe 110, a first sensor part 30L and a second sensor part 30M accommodated in the case member 11. , And a third sensor unit 30S and a control unit 40.
  • the case member 11 is formed in a bottomed cylindrical shape with the bottom side (the lower end side in the illustrated example) closed.
  • the length L in the cylinder axis direction of the case member 11 is formed to be substantially the same as the radius R of the exhaust pipe 110 so that the bottom cylindrical wall portion protrudes to the vicinity of the axial center CL of the exhaust pipe 110. ing.
  • the bottom side of the case member 11 is the front end side, and the side opposite to the bottom side is the base end side of the case member 11.
  • a plurality of inlets 12 arranged at intervals in the circumferential direction are provided on the distal end side cylindrical wall portion of the case member 11.
  • a plurality of outlets 13 arranged at intervals in the circumferential direction are provided in the base end side cylindrical wall portion of the case member 11.
  • the total opening area S12 of the inlet 12 is formed smaller than the total opening area S13 of the outlet 13 (S12 ⁇ S13). That is, the exhaust flow velocity V12 near the inlet 12 becomes slower than the exhaust flow velocity V13 near the outlet 13 (V12 ⁇ V13), so that the pressure P12 on the inlet 12 side becomes higher than the pressure P13 on the outlet 13 side. (P12> P13).
  • exhaust gas is smoothly taken into the case member 11 from the inlet 12, and at the same time, exhaust gas in the case member 11 is smoothly led out into the exhaust pipe 110 from the outlet 13.
  • the pedestal portion 20 includes a male screw portion 21 and a nut portion 22.
  • the male screw portion 21 is provided at the base end portion of the case member 11 and closes the base end side opening of the case member 11.
  • the male screw portion 21 is screwed with a female screw portion of a boss portion 110 ⁇ / b> A formed in the exhaust pipe 110.
  • the nut portion 22 is, for example, a hexagonal nut, and is fixed to the upper end portion of the male screw portion 21.
  • the male screw portion 21 and the nut portion 22 are formed with through holes (not shown) through which conductive wires 34L, 34M, 34S, 35L, 35M, 35S and the like described later are inserted.
  • the first sensor unit 30L includes a first filter member 31L and a plurality of pairs of first electrodes 32L and 33L.
  • the first filter member 31L constitutes a part of the collection portion of the present invention, and alternately upstream and downstream of a plurality of cells forming a grid-like exhaust flow path partitioned by porous ceramic partition walls. It is formed by plugging. Holding the first filter member 31L is the state that the flow channel direction of the cell substantially parallel to the axial direction of the case member 11 (vertical direction in the drawing), via a cushion member CM L to the inner circumferential surface of the case member 11 Has been. As indicated by the dashed arrows in FIG. 3, PM in the exhaust gas taken into the case member 11 from the inlet 12 is plugged upstream from the cell C1 L in which the exhaust gas is plugged downstream.
  • a cell whose downstream side is plugged is referred to as a first measurement cell C1 L
  • a cell whose upstream side is plugged is referred to as a first electrode cell C2 L.
  • First electrode 32L, 33L is, for example, a conductive metal wire, alternately from the downstream side (non-plugging side) electrode cell C2 L to opposite sides of the measurement cell C1 L of the first filter member 31L To form a capacitor.
  • the first electrodes 32L and 33L are connected to a capacitance detection circuit (not shown) built in the control unit 40 via first conductive lines 34L and 35L, respectively.
  • the second sensor unit 30M includes a second filter member 31M and a plurality of pairs of second electrodes 32M and 33M.
  • the second filter member 31M constitute a part of the collecting portion of the present invention, than the first filter member 31L, is disposed on the downstream side in the flow direction of the exhaust gas, the case member 11 via the cushion member CM M It is held on the inner peripheral surface of.
  • the second filter member 31M has a lower porosity (or smaller average pore diameter) than the first filter member 31L. That is, the second filter member 31M is provided with pores having a diameter smaller than the pores provided in the first filter member 31L, and traps PM in the exhaust gas that has not been collected by the first filter member 31L. Gather.
  • the second filter member 31M also includes the measurement cell C1 M whose downstream side is plugged and the electrode cell C2M whose upstream side is plugged, similarly to the first filter member 31L.
  • the second electrode 32M, 33M is, for example, a conductive metal wire, alternately from the downstream side (non-plugging side) to the second filter member 31M sandwiched therebetween cell for a counter electrode a measuring cell C1 M of C2 M To form a capacitor.
  • the second electrodes 32M and 33M are connected to the capacitance detection circuit via second conductive lines 34M and 35M, respectively.
  • the third sensor unit 30S includes a third filter member 31S and a plurality of pairs of third electrodes 32S and 33S.
  • Third filter member 31S may form part of the collecting portion of the present invention, than the second filter member 31M, it is disposed on the downstream side in the flow direction of the exhaust gas, the case member 11 via the cushion member CM S It is held on the inner peripheral surface of.
  • the third filter member 31S has a lower porosity (or smaller average pore diameter) than the second filter member 31M. That is, the third filter member 31S is provided with pores having a diameter smaller than the pores provided in the second filter member 31M, and the PM in the exhaust gas that has not been collected by the second filter member 31M is also obtained. Collect.
  • the third filter member 31S is also plugged on the measurement cell C1 S whose downstream side is plugged and the upstream side, similarly to the first filter member 31L and the second filter member 31M. and it has an electrode for cell C2 S.
  • Third electrode 34S, 35S is, for example, a conductive metal wire, alternating from the third filter member 31S measuring cell C1 electrode cell opposite to each other with respect to the S C2 S to the downstream side of the (non-plugging side) To form a capacitor.
  • the third electrodes 32S and 33S are connected to the capacitance detection circuit via third conductive lines 34S and 35S, respectively.
  • an electric heater 36 is provided for each of these sensor units 30L, 30M, and 30S.
  • the electric heater 36 is, for example, a heating wire, and constitutes the regenerating means of the present invention.
  • the electric heater 36 generates heat by energization and heats the measurement cells C1 L , C1 M , C1 S included in the filter members 31L, 31M, 31S, thereby burning and removing PM accumulated in the measurement cells.
  • Filter regeneration hereinafter also referred to as sensor regeneration
  • the electric heater 36 is formed by bending each filter member 31L, 31M, 31S into a continuous S-shape, and the straight portions parallel to each other are arranged inside the measurement cells C1 L , C1 M , C1 S. Is inserted along the flow path. Since the electric heater 36 of this embodiment arrange
  • the control unit 40 performs various controls, and includes a known CPU, ROM, RAM, input port, output port, and the like.
  • the control unit 40 includes a filter regeneration control unit 41, a first PM amount estimation unit 42, a second PM amount estimation unit 43, a third PM amount estimation unit 44, and a total PM amount estimation unit 45 as functional elements. I have. These functional elements are described as being included in the control unit 40 that is an integral piece of hardware, but may be provided in separate hardware.
  • the filter regeneration control unit 41 is an example of a regeneration unit according to the present invention, and includes a pair of electrodes 33L, 33M, and 33S that are paired with the electrodes 32L, 32M, and 32S detected by a capacitance detection circuit (not shown). Filter regeneration control is performed to turn on (energize) the electric heater 36 according to the capacitances Cp L , Cp M , and Cp S between them.
  • the capacitance Cp L between the first electrodes 32L and 33L is the dielectric constant ⁇ L of the medium between the first electrodes 32L and 33L, the surface area S L of the first electrodes 32L and 33L, and the first electrodes 32L and 33L. It is represented by the following mathematical formula (1) with a distance d L between them.
  • the surface area S L of the first electrodes 32L and 33L is constant, and when the dielectric constant ⁇ L and the distance d L are changed by PM collected in the measurement cell C1 L , the electrostatic capacity is increased accordingly.
  • the capacitance Cp L also changes. That is, a proportional relationship is established between the capacitance Cp L between the first electrodes 32L and 33L and the PM deposition amount of the first filter member 31L.
  • the capacitance Cp M between the second electrodes 32M and 33M is the dielectric constant ⁇ M of the medium between the second electrodes 32M and 33M, the surface area S M of the second electrodes 32M and 33M, and between the second electrodes 32M and 33M. It is expressed by equation (2) below to the distance d M.
  • the surface area S M of the second electrodes 32M and 33M is constant, and when the dielectric constant ⁇ M and the distance d M are changed by the PM collected in the measurement cell C1 M , the electrostatic capacity is increased accordingly.
  • the capacitance Cp M also changes. Therefore, the first electrode 32L, similarly to 33L, the second electrode 32M, a proportional relationship between the electrostatic capacitance Cp M and the PM accumulation amount of the second filter member 31M between 33M established.
  • the capacitance Cp S between the third electrodes 32S and 33S is the dielectric constant ⁇ S of the medium between the third electrodes 32S and 33S, the surface area S S of the third electrodes 32S and 33S, and between the third electrodes 32S and 33S. It is expressed by equation (3) below to a distance d S.
  • the surface area S S of the third electrodes 32S and 33S is constant, and when the dielectric constant ⁇ S and the distance d S are changed by PM collected in the measurement cell C1S, the capacitance is accordingly increased. Cp S also changes. Therefore, similarly to the first electrodes 32L, 33L, etc., a proportional relationship is established between the capacitance Cp S between the third electrodes 32S, 33S and the PM deposition amount of the second filter member 31S.
  • the first PM amount estimating unit 42, the second PM amount estimating unit 43, and the third PM amount estimating unit 44 estimate the PM accumulation amount of each filter member 31L, 31M, 31S.
  • the first PM amount estimation unit 42 is an example of the estimation means of the present invention, and the first PM amount collected by the first filter member 31L during the regeneration interval period from the end of the filter regeneration to the start of the next filter regeneration is the first amount.
  • An estimation calculation is performed based on the capacitance change amount ⁇ Cp L between the electrodes 32L and 33L.
  • the second PM amount estimation unit 43 is an example of the estimation means of the present invention, and the second PM amount collected by the second filter member 31M during the regeneration interval period from the end of the filter regeneration to the start of the next filter regeneration is the second An estimation calculation is performed based on the capacitance change amount ⁇ Cp M between the electrodes 32M and 33M.
  • the third PM amount estimation unit 44 is an example of the estimation means of the present invention, and the PM amount collected by the third filter member 31S during the regeneration interval period from the end of filter regeneration to the start of the next filter regeneration is the third electrode. An estimation calculation is performed based on the capacitance change amount ⁇ Cp S between 32S and 33S.
  • the interval period PM amount m PM_Int_L , m PM_Int_M , M PM_Int_S are sequentially calculated.
  • the filter regeneration control unit 41 includes electrostatic capacitances Cp L of the first electrodes 32L and 33L included in the first filter member 31L and electrostatics of the second electrodes 32M and 33M included in the second filter member 31M. Any of the capacitance Cp M and the capacitance Cp S of the third electrodes 32S and 33S provided in the third filter member reaches predetermined capacitance upper limit thresholds Cp L_max , Cp M_max , Cp S_max indicating the PM upper limit accumulation amount. Then, filter regeneration for turning on the electric heater 36 is started.
  • this filter regeneration is performed for all the filter units 30L, 30M, and 30S, and a predetermined capacitance lower limit threshold Cp L_min in which the capacitance of the target electrode indicates complete removal of PM. , Cp M_min , and Cp S_min .
  • the electrostatic capacitance Cp L of the first filter member 31L in the first interval period T 1 of the the filter regeneration time t 0 to the filter regeneration time t 1 has reached the capacitance upper threshold Cp L_max Therefore, filter regeneration is performed on the filter members 31L, 31M, and 31S.
  • the capacitance Cp S of the third filter member 31S reaches the capacitance upper limit threshold Cp S_max , and the filter regeneration time t 2. since the capacitance Cp M of the second filter member 31M reaches the electrostatic capacitance upper threshold Cp M_max in the third interval period T 3 from to filter regeneration time t 3, the filter member 31L, 31M, to 31S Filter regeneration is performed.
  • the total PM amount estimation unit 45 is a portion that estimates the PM amount accumulated in the entire sensor 10A. For this reason, the total PM amount estimating unit 45 receives the estimated values from the first PM amount estimating unit 42, the second PM amount estimating unit 43, and the third PM amount estimating unit 44 in real time, and adds them together to estimate the total PM amount. To get.
  • the regeneration interval period T n is calculated by calculating the interval PM amounts m PM_Int_L , m PM_Int_M , and m PM_Int_S based on the capacitance changes ⁇ Cp L , ⁇ Cp M , and ⁇ Cp S. It becomes possible to estimate the amount of PM in the exhaust gas discharged from the engine 100 in real time and with high accuracy.
  • the sensor 10A includes sensor units 30L, 30M, and 30S including three types of filter members 31L, 31M, and 31S having different hole diameters. And each sensor part 30L, 30M, 30S is arrange
  • the PM in the exhaust gas can be deposited on each filter member 31L, 31M, 31S in a state of being divided for each particle size, and the PM amount for each particle size can be estimated in real time and with high accuracy. Become.
  • the electric heater 36 is arranged in a series around the filter members 31L, 31M, and 31S, it suppresses a problem that PM deposited on another filter member is burned out by regeneration processing in one filter member. it can. This makes it possible to estimate the PM amount for each particle size with higher accuracy.
  • the case member 11 that houses the sensor unit 30 has its tip projecting in the exhaust pipe 110 to the vicinity of the axis center CL where the exhaust flow velocity is the fastest.
  • An inlet 12 that takes in exhaust gas into the case member 11 is provided in the cylindrical wall portion on the distal end side of the case member 11.
  • a outlet port 13 having an opening area larger than that of the inlet 12 is provided in the base end side cylindrical wall portion of the case member 11. That is, according to the PM sensor 10A of the present embodiment, the introduction port 12 is disposed in the vicinity of the axial center CL of the exhaust pipe 110 having a high exhaust flow rate, and the opening area of the outlet port 13 is increased, so that the introduction port 12 and the introduction port 12 are guided. A large static pressure difference from the outlet 13 can be secured, and the flow of exhaust gas passing through the sensor unit 30 can be effectively promoted.
  • the PM sensor 10A of the present embodiment is configured to reliably collect PM in exhaust gas by the filter members 31L, 31M, and 31S. Therefore, according to the PM sensor 10A, it is possible to effectively ensure the estimation accuracy of the PM amount even in an operation state in which the exhaust gas flow rate increases.
  • the PM sensor 10B of the second embodiment is a PM sensor 10A of the first embodiment in which the case member 11 has a double tube structure. Since other components have the same structure, detailed description thereof is omitted. Further, illustration of some components such as the control unit 40 is omitted.
  • the case member 11 of the second embodiment includes a bottomed cylindrical inner case portion 11A and a cylindrical outer case portion 11B surrounding the cylindrical outer peripheral surface of the inner case portion 11A.
  • the inner case portion 11A is formed to have a longer axial length than the outer case portion 11B so that the tip side protrudes from the outer case portion 11B.
  • a lead-out port 13 for leading the exhaust gas in the inner case portion 11A into the exhaust pipe 110 is provided at the bottom of the inner case portion 11A.
  • a plurality of passage openings 14 are provided in the cylindrical wall portion on the proximal end side of the inner case portion 11A and arranged at intervals in the circumferential direction. The passage port 14 allows the exhaust gas in the flow path 15 defined by the outer peripheral surface of the inner case portion 11A and the inner peripheral surface of the outer case portion 11B to pass through the inner case portion 11A.
  • annular introduction port 12 is formed which is partitioned by the distal end side cylindrical wall portion of the inner case portion 11 ⁇ / b> A and the distal end portion of the outer case portion 11 ⁇ / b> B.
  • the opening area S12 of the inlet 12 is formed smaller than the opening area S13 of the outlet 13 (S12 ⁇ S13).
  • the exhaust gas flowing through the exhaust pipe 110 hits the cylindrical wall surface of the inner case portion 11A protruding to the front end side from the outer case portion 11B, and flows from the introduction port 12 disposed in the vicinity of the axial center CL of the exhaust pipe 110 to the flow path 15. It is taken in smoothly. Further, the exhaust gas flowing in the flow path 15 is taken into the inner case portion 11A from the passage port 14, passes through the filter member 31, and then is exhausted from the outlet port 13 disposed in the vicinity of the axial center CL of the exhaust pipe 110. 110 is smoothly led out.
  • the inlet 12 and the outlet 13 are disposed in the vicinity of the axial center CL where the exhaust flow velocity is the fastest in the exhaust pipe 110, thereby passing through the filter member 31. It is possible to effectively increase the exhaust flow rate.
  • the sensor 10C of the third embodiment is obtained by replacing the sensor units 30L, 30M, and 30S of the first embodiment with stacked type sensor units 60L, 60M, and 60S.
  • the difference between the sensor units 60L, 60M, and 60S is the porosity of the filter layers 61L, 61M, and 61S. For this reason, the external appearances of the filter layers 61L, 61M, and 61S are the same.
  • the first electrode plates 62L, 62M, 62S and the second electrode plates 63L, 63M, 63S are the same member.
  • each filter layer 61L, 61M, 61S will be described as the filter layer 61
  • each first electrode plate 62L, 62M, 62S will be described as the first electrode plate 62
  • 63M, 63S will be described as the second electrode plate 63.
  • the conductive lines 64L, 64M, and 64S and the pair of conductive lines 65L, 65M, and 65S will be described as the conductive lines 64 and 65.
  • omitted since it becomes the same structure about other components other than each sensor part 60L, 60M, 60S, detailed description and illustration are abbreviate
  • FIG. 7A is a perspective view of each sensor unit 60L, 60M, 60S provided in the sensor 10C
  • FIG. 7B is an exploded perspective view of each sensor unit 60L, 60M, 60S.
  • Each sensor unit 60L, 60M, 60S includes a plurality of filter layers 61, a plurality of first and second electrode plates 62, 63, and conductive wires 64, 65.
  • the filter layer 61 is, for example, plugged alternately upstream and downstream of a plurality of cells that are partitioned by partition walls such as porous ceramics to form an exhaust passage, and these cells are arranged in parallel in one direction. It is formed in a rectangular parallelepiped shape.
  • the PM contained in the exhaust gas flows from the cell C11 whose downstream side is plugged into the cell C12 whose upstream side is plugged, as indicated by a broken line arrow in FIG. 7B. Thus, it is collected on the partition wall surface and pores of the cell C11.
  • the cell flow path direction is the length direction of each sensor unit 60L, 60M, 60S (arrow L in FIG. 7A), and the direction orthogonal to the cell flow path direction is each sensor unit 60L. , 60M, 60S in the width direction (arrow W in FIG. 7A).
  • the first and second electrode plates 62 and 63 are, for example, plate-like conductive members, and are formed so that the outer dimensions in the length direction L and the width direction W are substantially the same as those of the filter layer 61.
  • the first and second electrode plates 62 and 63 are alternately stacked with the filter layer 61 interposed therebetween, and are respectively connected to a capacitance detection circuit (not shown) built in the control unit 40 via the conductive lines 64 and 65. It is connected.
  • the first electrode plate 62 and the second electrode plate 63 are arranged to face each other, and the filter layer 61 is sandwiched between the electrode plates 62 and 63, whereby the entire cell C11 forms a capacitor. .
  • the electrode surface area S can be effectively secured, and a detectable static It becomes possible to increase the absolute value of the capacitance. Further, since the inter-electrode distance d becomes the cell pitch and is made uniform, variations in the initial capacitance can be effectively suppressed.
  • the sensor 10D of the fourth embodiment includes sensor units 70L, 70M, and 30S, 30M, and 30S of the first embodiment formed of ceramics having different porosities and average pore diameters. 70S.
  • FIG. 8 shows a cross-sectional view of the sensor portions 70L, 70M, and 70S of the sensor 10D in the exhaust flow direction.
  • Each sensor unit 70L, 70M, 70S includes filter layers 71L, 71M, 71S, first electrode plates 72L, 72M, 72S and second electrode plates 73L, 73M, 73S, and conductive wires 74, 75.
  • Each filter layer 71L, 71M, 71S is made of porous ceramics, and a plurality of holes 76L, 76M, 76S for collecting PM and wall parts 77L, 77M, 77S that form the holes 76L, 76M, 76S, respectively.
  • the porosity of the filter layer 71L is larger than the porosity of the filter layer 71M and the filter layer 71S.
  • the average pore diameter obtained by averaging the hole diameters of the respective holes 76L of the filter layer 71L is formed larger than the average pore diameters of the other filter layers 71M and 71S. That is, in this embodiment, the filter layers 71L, 71M, and 71S are arranged in the order of the high porosity (or the large average pore diameter) from the exhaust gas upstream to the downstream of the exhaust gas.
  • PM contained in the exhaust gas flowing into the sensor portions 70L, 70M, and 70S flows toward the holes 76L, 76M, and 76S defined by the wall portions 77L, 77M, and 77S.
  • PM having a diameter larger than the diameters of the holes 76L, 76M, and 76S of the sensor units 70L, 70M, and 70S is collected in the holes 76L, 76M, and 76S, while the PM having a diameter smaller than the diameters of the holes 76L, 76M, and 76S is collected. It passes through the holes 76L, 76M, 76S and flows downstream of the filter layers 71L, 71M, 71S.
  • the first electrode plates 72L, 72M, 72S and the second electrode plates 73L, 73M, 73S are, for example, plate-like conductive members, and the outer dimensions thereof are formed substantially the same as the filter layers 71L, 71M, 71S. ing.
  • the first electrode plates 72L, 72M, and 72S and the second electrode plates 73L, 73M, and 73S are arranged with the filter layers 71L, 71M, and 71S interposed therebetween, and are built in the control unit 40 through the conductive wires 74 and 75. Each is connected to a capacitance detection circuit (not shown).
  • the first electrode plates 72L, 72M, 72S and the second electrode plates 73L, 73M, 73S are arranged to face each other, and a filter is provided between the first electrode plates 72L, 72M, 72S and the second electrode plates 73L, 73M, 73S.
  • the holes 76L, 76M, 76S as a whole form a capacitor.
  • a heater substrate (not shown) may be interposed between the filter layers 71L, 71M, 71S and the first electrode plates 72L, 72M, 72S and the second electrode plates 73L, 73M, 73S.
  • the filter layers 71L, 71M, and 71S of the present embodiment are preferably formed of cordierite ceramics.
  • the filter layers 71L, 71M, and 71S may be members that have heat resistance, allow exhaust gas to pass through, and can grasp the porosity.
  • they can be applied as members constituting the filter layer.
  • a bypass pipe 190 that branches from between the oxidation catalyst 210 and the DPF 220 and joins upstream of the NOx purification catalyst 230 is connected to the exhaust pipe 110, and the sensor unit of the first embodiment.
  • 30L, 30M, 30S or the sensor units 60L, 60M, 60S of the third embodiment may be arranged in the bypass pipe 190.
  • the plurality of sensor units 30L, 30M, and 30S are heated together using a single electric heater 36.
  • an electric heater is individually provided for each sensor unit 30L, 30M, and 30S. Playback control may be performed.
  • the sensor unit to be regenerated and the sensor unit located on the downstream side in the exhaust gas flow direction with respect to the sensor unit are collectively subjected to regeneration processing. That is, when the amount of particulate matter accumulated in the cell of one filter member becomes a predetermined amount or more, a plurality of filter members including the filter member and a filter member adjacent to the filter member downstream are provided. Perform filter regeneration to heat and remove particulate matter by combustion. This is because the PM accumulated on the downstream side may be burned down by the heated exhaust gas generated during the regeneration process of the upstream sensor unit.
  • filter members 31L, 31M, and 31S having different pore sizes are provided, but the number of types of filter members is not limited to this. It is sufficient that two or more types of filter members are provided.
  • the positions of the inlet 12 and the outlet 13 are switched to reverse the flow of the exhaust gas introduced into the case member 11. You may make it face.
  • the filter members 31L, 31M, and 31S may be inverted and accommodated in the case member 11.
  • the sensor of the present invention is useful in that the amount of PM for each particle size of PM contained in exhaust gas can be continuously estimated.

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  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)

Abstract

L'invention concerne un capteur qui comprend : des pièges (30L 30M, 30S) dans lesquels une pluralité d'éléments filtrants destinés à piéger des substances particulaires dans les gaz d'échappement sont agencés selon un ordre de porosité plus élevée depuis l'extrémité amont jusqu'à l'extrémité aval des gaz d'échappement; des électrodes (32, 33) agencées sur les éléments filtrants (30L, 30M, 30S) de sorte à être orientés les uns vers les autres, les éléments filtrants (30L, 30M, 30S) étant intercalés entre ces derniers; et des unités d'estimation (42 à 44) destinées à estimer respectivement, pour chaque élément filtrant, la masse particulaire piégée respectivement par les éléments filtrants (30L, 30M, 30S) ayant des porosités différentes, sur la base de l'importance du changement de la capacité électrostatique entre les paires d'électrodes (32, 33).
PCT/JP2016/051481 2015-01-20 2016-01-19 Capteur WO2016117577A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
CN201680006239.7A CN107209099A (zh) 2015-01-20 2016-01-19 传感器
EP16740184.3A EP3252453B1 (fr) 2015-01-20 2016-01-19 Capteur
US15/545,213 US10481061B2 (en) 2015-01-20 2016-01-19 Sensor for detecting an emission amount of particulate matter

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2015-008668 2015-01-20
JP2015008668 2015-01-20
JP2016-004641 2016-01-13
JP2016004641A JP6766358B2 (ja) 2015-01-20 2016-01-13 センサ

Publications (1)

Publication Number Publication Date
WO2016117577A1 true WO2016117577A1 (fr) 2016-07-28

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PCT/JP2016/051481 WO2016117577A1 (fr) 2015-01-20 2016-01-19 Capteur

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Country Link
WO (1) WO2016117577A1 (fr)

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002021537A (ja) * 2000-07-03 2002-01-23 Nissan Diesel Motor Co Ltd ディーゼルエンジンの排気浄化装置
JP2003098136A (ja) * 2001-09-27 2003-04-03 Horiba Ltd 粒子状物質センサ−およびこれを用いた粒子状物質の測定方法
JP2007524786A (ja) * 2004-02-12 2007-08-30 ダイムラークライスラー・アクチェンゲゼルシャフト パティキュレートフィルタの状態判定装置
JP2009042021A (ja) * 2007-08-08 2009-02-26 Mazda Motor Corp パティキュレート排出量検出装置
JP2009097410A (ja) * 2007-10-16 2009-05-07 Toyota Motor Corp パティキュレートフィルタにおけるｐｍ捕集量推定装置およびフィルタ再生システム
JP2012117383A (ja) * 2010-11-29 2012-06-21 Isuzu Motors Ltd Ｐｍセンサ及びｐｍセンサ製造方法
WO2012104994A1 (fr) * 2011-02-01 2012-08-09 トヨタ自動車株式会社 Dispositif de commande pour moteur à combustion interne
WO2012160950A1 (fr) * 2011-05-20 2012-11-29 いすゞ自動車株式会社 Détecteur de matières particulaires
JP2013205034A (ja) * 2012-03-27 2013-10-07 Honda Motor Co Ltd 粒子状物質検出装置
WO2014129448A1 (fr) * 2013-02-20 2014-08-28 いすゞ自動車株式会社 Dispositif de mesure d'une substance particulaire

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002021537A (ja) * 2000-07-03 2002-01-23 Nissan Diesel Motor Co Ltd ディーゼルエンジンの排気浄化装置
JP2003098136A (ja) * 2001-09-27 2003-04-03 Horiba Ltd 粒子状物質センサ−およびこれを用いた粒子状物質の測定方法
JP2007524786A (ja) * 2004-02-12 2007-08-30 ダイムラークライスラー・アクチェンゲゼルシャフト パティキュレートフィルタの状態判定装置
JP2009042021A (ja) * 2007-08-08 2009-02-26 Mazda Motor Corp パティキュレート排出量検出装置
JP2009097410A (ja) * 2007-10-16 2009-05-07 Toyota Motor Corp パティキュレートフィルタにおけるｐｍ捕集量推定装置およびフィルタ再生システム
JP2012117383A (ja) * 2010-11-29 2012-06-21 Isuzu Motors Ltd Ｐｍセンサ及びｐｍセンサ製造方法
WO2012104994A1 (fr) * 2011-02-01 2012-08-09 トヨタ自動車株式会社 Dispositif de commande pour moteur à combustion interne
WO2012160950A1 (fr) * 2011-05-20 2012-11-29 いすゞ自動車株式会社 Détecteur de matières particulaires
JP2013205034A (ja) * 2012-03-27 2013-10-07 Honda Motor Co Ltd 粒子状物質検出装置
WO2014129448A1 (fr) * 2013-02-20 2014-08-28 いすゞ自動車株式会社 Dispositif de mesure d'une substance particulaire

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