JP5709808B2 - Particulate matter detection element manufacturing method and particulate matter detection sensor - Google Patents

Description

  The present invention relates to a method for manufacturing a particulate matter detection element that is used in an exhaust system of an internal combustion engine for automobiles, etc., and detects particulate matter mainly composed of soot composed of carbon contained in a gas to be measured, and particles TECHNICAL FIELD OF THE INVENTION

In automobile diesel engines and the like, environmental pollutants contained in combustion exhaust, particularly particulate matter (hereinafter referred to as PM) mainly composed of soot particles and soluble organic components (SOF) are collected. For this purpose, a diesel particulate filter (hereinafter referred to as DPF) is installed in the exhaust passage. The DPF is made of porous ceramics having excellent heat resistance, and traps PM by allowing combustion exhaust gas to pass through partition walls having a large number of pores.
If the amount of collected PM exceeds the allowable amount, the DPF will become clogged and the pressure loss will increase, or the DPF will be damaged by the heat generated when burning excessively accumulated PM, causing the PM to pass through. The collection ability is restored by periodically performing a regeneration process.

Various PM detection sensors for detecting PM in the gas to be measured have been proposed in order to appropriately detect the DPF regeneration timing and to detect abnormalities such as PM slipping at an early stage.
For example, in Patent Document 1, PM in a measurement gas is deposited between a pair of comb electrodes facing a surface of an insulator with a predetermined gap therebetween, and a resistance value that changes according to the amount of deposition, There is disclosed a PM detecting element that measures electrical characteristics such as capacitance and impedance and detects the amount of PM contained in a gas to be measured.
Patent Document 2 discloses a plate-shaped element base, a pair of measurement electrodes disposed on the element base, characteristic measurement means for measuring electrical characteristics between the pair of measurement electrodes, and the above A pair of the measurement electrodes and a particulate matter amount calculation means for obtaining the amount of particulate matter collected around the measurement electrodes based on a change amount of the electrical characteristics measured by the property measurement means; Each measurement electrode constituting the measurement electrode has a comb-tooth shape having a plurality of comb-tooth portions arranged in a plane and a comb-bone portion connecting the plurality of comb-tooth portions of each measurement electrode at one end thereof. The comb teeth of each of the measurement electrodes are arranged so as to be engaged with each other with a gap, and the comb bone of at least one of the measurement electrodes is a dielectric. Particulate matter covered by a comb bone covering portion comprising Out apparatus is disclosed. This particulate matter detection apparatus detects particulate matter by attaching a particulate matter to a pair of measurement electrodes and the periphery thereof and measuring a change in electrical characteristics between the pair of measurement electrodes.

  In such a conventional PM detection element, thick film printing, chemical vapor deposition (CVD), thin film printing such as physical vapor deposition (PVD), etc. are performed on the surface of an insulating substrate such as alumina or a conductive substrate such as zirconia. A technique is used in which a plurality of electrodes formed in a substantially strip shape are arranged at regular intervals and are opposed to each other so that the polarities are alternately changed, and a so-called comb-like pattern is used. In the PM detection element with the comb-like electrodes facing each other, there is a dead mass that cannot detect the electrical characteristics between the electrodes until the amount of PM deposited between the pair of electrodes exceeds a certain amount, and an abnormality of the DPF It is desired to reduce this dead mass as much as possible in order to detect the above in an early and reliable manner.

Further, when a certain amount or more of PM is accumulated between the detection electrodes and becomes saturated, the electrical characteristics detected between the detection electrodes become constant, and the PM in the gas to be measured cannot be detected.
Therefore, in the PM detection device, in order to continue the PM detection, when the amount of PM adhering between the detection electrodes reaches a limit, the attached PM is burned and removed by heating with a heater or the like to detect the PM. Is trying to play.

  Furthermore, in Patent Document 3, in such a gas sensor, a disconnection detection resistor having a predetermined resistance value is paired as a disconnection detection unit that detects the presence or absence of a disconnection of a conduction path that connects between the detection unit and the resistance measurement unit. Disclosed is a gas sensor characterized in that it is provided on the side of the resistance measuring means so as to conduct the detection electrode and to be in parallel with the detection resistance formed between the detection electrodes. It is possible.

However, in the conventional PM detection element, when forming a comb-like electrode, when using a general thick film printing, the gap between the detection electrodes is about several tens of μm, and the rheological characteristics of the printing paste and About 20 μm was the limit due to restrictions on the production of the mask formed on the printing screen.
In addition, when thin film printing such as CVD or PVD is used, it is possible to form a very precise pattern, but on the other hand, the equipment cost is high and the manufacturing cost may be increased.
In addition, since the detection electrode to be formed is necessarily a thin film, it is provided in the combustion exhaust passage of an internal combustion engine such as an automobile engine, and the vibration from the outside, the temperature change of the measured gas, and the PM detection element are heated. In PM detection elements that are directly exposed to extremely harsh usage environments such as thermal stress when burning and removing PM deposited on the detection unit, and thermal stress due to adhesion of moisture contained in the gas to be measured, There is a risk that transpiration, peeling, and the like may occur, and sufficient durability may not be obtained.

  Furthermore, in a particulate matter detection element that detects electrical characteristics that change according to the amount of particulate matter deposited between a pair of electrodes, the change in resistance value between the detection electrodes is measured as electrical characteristics. However, even in the case of measuring capacitance, the state where a disconnection due to some defect occurs in each detection electrode and the state where no particulate matter is deposited between the detection electrodes are electrically equivalent. Therefore, there is a possibility that it is not possible to distinguish between a defect such as a disconnection in the detection electrode and a state where PM is not deposited between the detection electrodes.

  Accordingly, in view of such circumstances, the present invention measures the electrical characteristics that change according to the amount of particulate matter contained in the measurement gas deposited on the detection unit, and thereby determines the amount of particulate matter in the measurement gas. Provides a method for manufacturing a particulate matter detection element having a structure with extremely low dead mass and high measurement accuracy, and detecting particulate matter using the particulate matter detection element An object of the present invention is to provide a highly reliable particulate matter detection sensor that can detect the presence or absence of a defect such as a disconnection in an element.

In the present invention (1,1a, 1b, 1c, 1d ), the first detection electrodes face each other with at least a predetermined distance (EL _A), detecting unit comprising a second detection electrode _(EL B) (10, 10c, 10d) in the gas to be measured by detecting electrical characteristics between the first detection electrode and the second detection electrode , which change according to the amount of particulate matter collected and deposited on (10, 10c, 10d) A particulate matter detection sensor comprising a particulate matter detection element (2, 2, 2b, 2c, 2d) for detecting the amount of particulate matter contained in
The first detection electrode (EL _A ) forms a conduction path connected in series from one end (103A , 103Ac , 103Ad ) to the other end (104A , 104Ac , 104Ad ). In the above detection part, a detection electrode facing part (101A , 101Ad ) , a part of which is bent in a U shape, and a detection electrode facing part (120) facing each other via an insulating layer (120) forming a predetermined distance between the detection electrodes 100A ), and
The second detection electrode (EL _B ) forms a conduction path connected in series from one end (103B, 103Bc, 103Bd) to the other end (104B, 104Bc, 104Bd). In the detection part, the second detection electrode folded part (101B, 101Bd), a part of which is bent in an inverted U shape, is opposed to an insulating layer (120) that forms a predetermined distance between the detection electrodes. A second sensing electrode facing portion (100B) that
The first detection one end of the electrode (103A, 103Ac, 103Ad) the other end of the first detection electrode from (104A, 104Ac, 104Ad) by the measurement of the resistance value of up to, the first _A first disconnection detection circuit section (301A, 301Aa, 301Ab ) for detecting the presence or absence of disconnection inside the detection electrode (EL _A ) of
By measuring the resistance value from one end (103B, 103Bc, 103Bd) of the second detection electrode to the other end (104B, 104Bc, 104Bd) of the second detection electrode, A first disconnection detection circuit portion (301B, 301Ba, 301Bb) for detecting the presence or absence of disconnection in the detection electrode (EL _B ) .

In addition, the present invention provides a configuration between one end of the first detection electrode and one end of the second detection electrode (103A-103B, 103Ac-103Bc, 103Ad-103Bd), or the first the other end of the first detecting electrodes, the during the second detection electrode (104A-104B, 104Ac-104Bc , 104Ad-104Bd) resistance of the capacitance, either by detection of the impedance, said first A PM detection circuit unit (31) for detecting the amount of particulate matter deposited between one detection electrode and the second detection electrode is provided.
Further, according to the present invention, the particulate matter detection element (2, 2b, 2c, 2d) includes the detection unit (10, 10c, 10d) and a substrate unit (20, 20b, 20c, 20d) on which the detection unit is mounted. The detection portion (10, 10c, 10d) is formed in a substantially flat plate shape with a film thickness of 100 μm or more and 500 μm or less and the first detection electrode facing portion (100A ) and the second detection electrode facing Part ( 100B) and the laminated structure in which the insulating layer (120) formed in a substantially flat shape with a film thickness of 5 μm or more and 20 μm or less is repeatedly laminated, and the end surface in the stacking direction is used as a detection surface. Is .

According to the present invention, the particulate matter that detects the amount of particulate matter in the measurement gas by measuring the electrical characteristics that change according to the amount of particulate matter contained in the measurement gas deposited on the detection unit. in substance-detecting element, the said first disconnection detecting circuit section the presence or absence of internal defects (301A) by said first detection electrode _(EL a) from one end (103A) of the first detection electrode Detected by measuring the DC resistance up to the other end (104A ) of the first detection electrode, and detected by the second disconnection detection circuit (301B) inside the second detection electrode (EL _B ). The presence or absence of a defect is detected by measuring the DC resistance from one end (103B) of the second detection electrode to the other end (104B) of the second detection electrode . first detecting electrodes (EL _a) and the second test To detect the electrodes the PM detection circuit an electrical characteristic that varies depending on the amount of the particulate matter deposited between (EL _B) (31), is detected electrical characteristics as in the prior art, There is no fear that it may be impossible to distinguish whether the defect is due to a defect in the detection electrode such as a disconnection or the absence of particulate matter between the detection electrodes, and high reliability can be maintained.
In addition, by forming the detection section (10 , 10c, 10d ) with a laminated structure and using the cross section in the lamination direction as a detection surface, the film of the insulating layer (120) that can be formed extremely thin of 20 μm or less the thickness of it is possible to form the detection electrode pair distance has the following short-20μm the distance between the first detection electrode and the second detection electrode, insensitive mass is extremely small, high measurement system structure A method for producing a particulate matter detection element can be provided.
In conventional methods such as thick film printing, it is extremely difficult to form the gap between the detection electrodes to 20 μm or less, but by taking a laminated structure as in the present invention, the insulating layer (120) can be easily formed to 5 μm to 20 μm. It becomes possible to form in the following ranges, and extremely insensitive mass can be reduced.
_{Furthermore, LNF (LaNi 0.6 Fe 0.4 O} 3), LSN (La 1.2 Sr 0.8 NiO 4), LSM (La 1-X Sr X MnO 3-δ), LSC (La 1-X _{Sr X CoO 3-δ),} LCC (La 1-X Ca X CrO 3-δ), LSCN (La 0.85 Sr 0.15 Cr 1-X Ni X O 3-δ) (0.1 ≦ X ≦ 0.7) a perovskite-type conductive oxide material selected from any one of the above, a substantially flat conductive thick film sheet (100 _THK ) having a thickness of 100 μm to 500 μm, and a conductive material of the same material A substantially flat conductive thin film sheet (100 _THN ) having a film thickness of 5 μm or more and 20 μm or less is formed using a conductive oxide material , and 8YSZ ((ZrO ₂ ) _0.92 (Y ₂ O ₃ ) _0.08 ) Partial stabilization dice Using an insulating oxide material selected from Luconia, MgO, and Al ₂ O ₃ , a substantially flat insulating thick film sheet (120 _THK ) having a thickness of 100 μm to 500 μm, and the same material A substantially flat insulating thin film sheet (120 _THN ) having a film thickness of 5 μm or more and 20 μm or less is formed using an insulating oxide material, and a predetermined shape is formed at a predetermined position of the conductive thick film sheet (100 _THK ). Insulating thick film sheet (120 _THK ) embedded in an insulating thick film sheet embedded conductive thick film sheet (A layer, B layer) and insulating thin film sheet (120 THN) are partitioned into predetermined shapes at predetermined positions A conductive thin film sheet embedded with a conductive thin film sheet (100THN) and an insulating thin film sheet (MA layer, MB layer, C layer) are laminated in a predetermined repeating pattern. Accordingly, the first detection electrode (EL _A ) has a folded portion (101A, 101Ad) in which a part of the detection portion (10, 10c, 10d) is bent in a U shape, and a predetermined distance between the detection electrodes The first detection electrode facing portion (100A) facing the other detection portion via the insulating layer (120) forming the second detection electrode (EL _B ) is disposed on the detection portion (10, 10c). 10d), the folded portion (101B, 101Bd), a part of which is bent in an inverted U shape, and the other detection electrode are opposed to each other through an insulating layer (120) that forms a predetermined distance between the detection electrodes. A particulate matter detection sensor including the second detection electrode facing portion (100B) can be realized.

The schematic diagram which shows the basic composition of the particulate matter detection sensor of this invention. The block diagram which shows the whole outline | summary of the particulate matter detection sensor in the 1st Embodiment of this invention. The perspective view which shows the outline | summary of the detection electrode laminated body which is the principal part of the particulate matter detection element in the 1st Embodiment of this invention. FIG. 2B is a cross-sectional view of the detection electrode laminate along AA in FIG. 2A. FIG. 2 is a developed perspective view showing an outline of a particulate matter detection element according to the first embodiment of the present invention. The equivalent circuit diagram which shows the operation state of this invention in the time of normal. The equivalent circuit diagram which shows an example of the operation state of this invention at the time of a disconnection. The equivalent circuit diagram which shows the operation state at the time of the normal of a comparative example. The equivalent circuit diagram which shows the problem of a comparative example and shows an example of the operation state at the time of a disconnection. Sectional drawing for demonstrating the embedding process in the manufacturing method of the detection electrode laminated body which is the principal part of the particulate matter detection element in 1st Embodiment. FIG. 6B is a developed perspective view illustrating the detailed structure of the detection electrode laminate and explaining the outline of the lamination step subsequent to FIG. 6A. The perspective view which shows the outline | summary of the detection electrode laminated body cutting-out process following FIG. 6B. The block diagram which shows the outline | summary of the particulate matter detection sensor in the 2nd Embodiment of this invention. The block diagram which shows the outline | summary of the particulate matter detection sensor in the 3rd Embodiment of this invention. The perspective view which shows the outline | summary of the particulate matter detection element in the 4th Embodiment of this invention. FIG. 9B is a developed perspective view showing a detailed structure of the detection electrode laminate of FIG. 9A. The block diagram which shows the whole outline | summary of the particulate matter detection sensor in the 5th Embodiment of this invention. FIG. 10B is a developed perspective view showing an example of a detailed structure of the detection electrode laminate of FIG. 10A.

With reference to FIG. 1A, the basic structure of the particulate matter detection sensor 1 of the present invention will be described. FIG. 1A is a conceptual diagram expressing the basic configuration of the particulate matter detection sensor 1 of the present invention in a most simplified manner.
The particulate matter detection sensor 1 determines the amount of particulate matter collected and deposited on the detection unit 10 including the first detection electrode EL _A and the second detection electrode EL _B facing each other at least at a predetermined distance. first detecting electrode EL _a and particulate matter detection device that detects the amount of particulate matter by detecting electrical characteristics contained in the measurement gas between the second detection electrode EL _B which varies in accordance 2 and the circuit unit 3.
The particulate matter detection element 2 includes a detection unit 10 and a substrate unit 20 on which the detection unit 10 is mounted.

Detector 10, at least, are formed by a laminate structure having a first detection electrode EL _A and the second detection electrode EL _B which opposition via an insulating layer 120.
The first detection electrode EL _A and the second detection electrode EL _B are displayed with different hatching for the sake of convenience in order to distinguish which one is the electrode, but both electrodes are made of the same material. It is.
Specific materials will be described later together with the manufacturing method.
The circuit unit 3 includes a detection electrode disconnection detection circuit unit 30 that detects the presence or absence of internal disconnection between the first detection electrode EL _A and the second detection electrode EL _B, and the amount of particulate matter deposited between the detection electrodes. And a PM detection circuit unit 31 that detects electrical characteristics that change in response to the above.

The detection electrode disconnection detection circuit unit 30 includes a first detection electrode disconnection detection circuit unit 301A and a second detection electrode disconnection that detect the presence or absence of disconnection in each of the first detection electrode EL _A and the second detection electrode EL _B. It is comprised by the detection circuit part 301B.
First detecting electrode disconnection detecting circuit section 301A, for example, the resistance value up to the PM detection terminal 104A provided from the first detection electrodes EL one disconnection detecting terminal portion 103A provided at the end of the _A to the other end detecting the presence or absence of internal breakage of the first detection electrode EL _a by detecting.
Similarly, the second detection electrode disconnection detecting circuit section 302B, the resistance up to the second detecting electrodes EL one PM detection terminal 104B from the disconnection detection terminal portion 103B provided at an end provided at the other end of the _B detecting the presence or absence of internal breakage of the second detection electrode EL _B to detect the value.
Methods for detecting specific breakage, by measuring the potential difference between both ends by flowing a weak current, the internal resistance R _ELA of the first detection electrode EL _A, the internal resistance R of the second detection electrode EL _B enables measurement of _ELB, by comparing these with a predetermined threshold, it can be determined whether the disconnection.

In the present invention, the first detection electrode EL _A is a first detecting electrode folded portion 101A folded back in the detection unit 10 a portion of the first detection electrode facing portion 100A which is a generally flat plate shape substantially U-shape comprises a, connected to the first detection lead 102A, via the first detection lead 102A, a first disconnection detecting terminal 103A, and the state of being connected to the first PM detection terminal 104A it is, until the PM detection terminal 104A from the first disconnection detecting terminal 103A is characterized in that it is a single stroke manner to form a single conductive path without connected in series to branching.
Similarly, the second detection electrode EL _B has a shape obtained by inverting the first detection electrode EL _A by 180 °, and detects a part of the second detection electrode facing portion 100B formed in a substantially flat plate shape. The second detection electrode folded portion 101B folded in a substantially inverted U shape at the portion 10 is connected to the second detection lead portion 102B, and the second disconnection detection is performed via the second detection lead portion 102B. The terminal 103B and the second PM detection terminal 104B are connected to each other, and one conductive connected in series without branching from the second disconnection detection terminal 103B to the PM detection terminal 104B. It is characterized by a single stroke that forms a path.
The presence or absence of reliably broken by a shape having a first detection electrode EL _A and the second detection electrode EL _B and such unbranched continuous conductive path can be detected.

The PM detection circuit unit 31 is one of DC resistance, capacitance, and AC impedance that changes according to the amount of particulate matter deposited between the first detection electrode EL _A and the second detection electrode EL _B. the electrical properties of, (between 103A-103B) first between the one end portion 103A and one end 103B of the second detection electrode EL _B of the detection electrodes EL _a, or first detection electrode It is detected by measuring one of the resistance value, capacitance, and impedance between the other end 104A of EL _{A and} the other end 104B of the second detection electrode EL _B ( between 104A and 104B ) The amount of particulate matter contained in the measurement gas can be calculated.
The substrate unit 20 is provided with a heating element 220 that generates heat when energized to stabilize the temperature at the time of detection, or to burn off and remove particulate matter deposited on the surface of the detection unit 10 for sensor regeneration. You may make it use.
Energization of the heating element 220 can be controlled by a heat generation control circuit unit 32 described later.

With reference to FIG. 1B, FIG. 2A, FIG. 2B, and FIG. 3, the more specific structure of the particulate matter detection sensor 1 in this embodiment is demonstrated.
As shown in FIG. 1B, the particulate matter detection sensor 1 in this embodiment is covered with a housing 4 (not shown) and is subjected to measurement such as combustion exhaust discharged from an internal combustion engine, as with a known particulate matter detection sensor. It is used in a state of being fixed to the measurement gas flow path 5 through which gas flows.
The particulate matter detection element 2 is fixed in a substantially cylindrical housing 4 via a known fixing member such as an insulator so that the detection unit 10 fixed to the tip of the substrate unit 20 is exposed to the gas to be measured. It has become.

In the present embodiment, as shown in FIG. 2A, in the detector 10, so that the detection electrode EL _A of hemorrhoids 1 and the second detection electrode EL _B are opposed at a plurality of places, first to the plurality of locations The detection electrode folded portion 101A and the second detection electrode folded portion 101B are provided, and the first detection electrode facing portion 100A bent in a U shape and the second detection electrode facing portion 100B bent in an inverted U shape are alternately arranged. It is formed in a comb-like aligned plurality opposite the.
However, also in this embodiment, as described above, without branching from the first disconnection detecting terminal 103A up to the first PM detection terminal 104A, the second PM detection terminal 104B from the second disconnection detecting terminal 103B up to, without branching, respectively constitute the conductive path in series of one.

In the present embodiment, as shown in FIG. 2A, a first disconnection detecting terminal 103A and a first PM detection terminal 104A, to be placed at one end of the detection portion 10, the first return lead A part 105A is formed, and a second return lead part 105B is formed so that the second disconnection detection terminal 103B and the second PM detection terminal 104B are arranged at one end of the detection part 10 .
Furthermore, the detection unit 10 in the present embodiment does not print and form an electrode pattern on the surface of a conventional insulating substrate, but as shown in FIG. 2B, the first detection electrode facing portion 100A formed in a flat plate shape. And a second detection electrode facing part 100B and an insulating layer 120 for forming a predetermined distance between the detection electrode pairs.

On the other hand, in this embodiment, as shown in FIG. 2B, the film thickness in the stacking direction of the first detection electrode facing portion 100A and the second detection electrode facing portion 100B is formed to be 100 μm or more and 500 μm or less. The thickness of 120 in the stacking direction is 5 μm or more and 20 μm or less.
The first detection electrode EL _A exposed on the surface of the detection unit 10 is formed by forming the insulating layer 120 to be extremely thin and stacking the first detection electrode facing part 100A and the second detection electrode facing part 100B. When the distance in the stacking direction between the second detection electrode EL _B, it becomes possible to set a very short distance of 5μm or 20μm or less, it is possible to eliminate the dead weight.
A specific manufacturing method in which the detection unit 10 has such a laminated structure will be described later.

As shown in FIG. 3, the substrate portion 20 in the present embodiment includes a heating element 220 that generates heat when energized between substantially flat insulating substrates 200 and 210, and is formed on the surface of the insulating substrate 200. The first PM detection terminal connection unit 106A, the second PM detection terminal unit 106B, the first disconnection detection terminal connection unit 107A, and the second disconnection detection terminal unit by known methods such as thick film printing and plating. 107B, first lead portions 108A, 109A, second lead portions 108B , 109B , a first PM detection external connection terminal 110A, a second PM detection external connection terminal 110B, a first disconnection detection external connection terminal 111A, A predetermined conductor pattern including the second disconnection detection external connection terminal 111B is formed.
The first disconnection detection terminal 103A of the detection unit 10 is the first disconnection detection terminal connection unit 107A, the second disconnection detection terminal 103B is the second disconnection detection terminal connection unit 107B, and the first PM detection terminal. 104A is connected to the first PM detection terminal connection portion 106A and the second PM detection terminal 104B is connected to the second PM detection terminal connection portion 106B, and is mounted and fixed on the surface of the substrate portion 20. Yes.
On the surface of the insulating substrate 210 formed in a substantially flat plate shape, a heating element 220 and a pair of heating element lead portions 221A and 221B are formed by a known method such as thick film printing and plating, and generate heat when energized. The heating element 220 and the heating element lead portions 221A and 221B are covered with the insulating substrate 200, and the heating element terminal portions 223A and 223B provided on the back side of the insulating substrate 210 through the through-hole electrodes 222A and 222B. It is connected to the.

The effect of the particulate matter detection sensor 1 in the first embodiment of the present invention will be described with reference to FIGS. 4A and 4B, and the conventional insulation shown as a comparative example with reference to FIGS. 5A and 5B A problem of the particulate matter detection sensor 1z in which a pair of comb-like electrodes are formed thick on the surface of the substrate will be described.
When the particulate matter detection sensor 1 of the present invention is used, the first detection electrode EL _A has both ends (between 103A and 104A ) and the second detection electrode EL _B has both ends ( between 103B and 104B) . resistance value detected by the first disconnection detecting circuit portion 301A and the second disconnection detecting circuit 301 B is the internal resistance R _ELA of the first detection electrode EL _a, and the internal resistance of the second detection electrode EL _B In addition to R _ELB, it is affected by particulate matter deposited on the surfaces of the first detection electrode EL _A and the second detection electrode EL _B.
At this time, the resistance paths formed by the deposition of the particulate matter are the first detection electrode facing portions 100A of the first detection electrodes EL _A facing each other and the second detection electrodes EL _B of the second detection electrodes EL _B. Since the detection electrode facing portions 100B are formed so as to bridge each other, as shown in FIG. 4A, the internal resistance r _PM formed by the deposition of the particulate matter is the internal resistance R _{ELA of} the first detection electrode EL _A. and, it would be connected in parallel to the internal resistance R _ELB of the second detecting electrodes EL _B, are detected by the respective ends of the first detecting electrode EL _a and the second detection electrode EL _B a first detection resistance value _{R a} and the second detection resistor R _B,
1 / R _A = 1 / R _ELA + 1 / r _PM ,
The relationship 1 / R _B = 1 / R _ELB + 1 / r _PM is established.

Internal resistance _{R ELA} of the first detection electrode EL _A, and the internal resistance R _ELB of the second detecting electrodes EL _B, for example, when about 1Omu～200omu, resistance path formed by deposition of particulate matter The resistance value r _PM of both ends of the first detection electrode EL _A and both ends of the second detection electrode EL _B even if the resistance value r _PM changes to about 1000Ω to 10 ⁶ Ω depending on the amount of particulate matter deposited. The first detection resistance value R _A and the second detection resistance value R _B detected in Step 1 are about 0.999Ω to 199.96Ω, and the first detection electrode EL _A and the second detection electrode EL _B are detected. When a disconnection occurs in any of the conduction paths, either the first both-end resistance value R _A or the second both-end resistance value R _B is 1000Ω or more.
For this reason, as shown in FIG. 4B, the internal resistance R _{ELA of} the first detection electrode EL _A , or the internal resistance R _ELB of the second detection electrode EL _B in which the disconnection occurs, is 10 ⁵ Ω or more. Therefore, in the first disconnection detection circuit unit 301A or the second disconnection detection circuit unit 301B, the first detection resistor R _A , the second detection resistor R _B, and a predetermined resistance threshold R _REF ( For example, by providing the first disconnection determination unit 302A and the second disconnection determination unit 302B, the presence / absence of disconnection can be detected very easily.

In addition, as an electrical characteristic that varies depending on the amount of the particulate matter deposited in between the first detection electrode EL _A and the second detection electrode EL _B facing, PM between the PM detection terminals 104A-104B When the derived resistance _RPM is measured, only a change in resistance value due to the amount of particulate matter deposited can be detected.
In addition, when a disconnection is detected, the particulate matter calculation can be stopped by issuing an abnormality warning.

On the other hand, when a conventional particulate matter detection sensor 1z in which a pair of detection electrodes facing each other with a predetermined gap are formed on a surface of an insulating substrate in a comb-like shape by thick film printing is used in a normal state, FIG. as shown in 5A, the detection resistor _{R SUM} is detected between the detection electrodes, the internal resistance _{r a} of the first detection electrode _{EL AZ,} and the internal resistance r _B of the second detecting electrodes EL _BZ, particulate matter It is equivalent to the PM-derived resistance R _PM that changes according to the amount of deposit Q _PM in series, and the PM accumulated amount Q _PM can be calculated by measuring the combined resistance R _PM + r _A + r _B It becomes.

However, in the conventional particulate matter detection sensor 1z, when a disconnection abnormality occurs somewhere in the first detection electrode EL _AZ and the second detection electrode EL _BZ , as shown in FIG. resistance and R _PM is in a state of being connected in series, PM-derived resistance is varied in a large range up 1000Ω~10 ⁶ Ω, the detection resistor is about 10 ⁵ Omega when disconnection occurs, disconnection It may not be possible to distinguish between the detection electrodes EL _AZ and EL _BZ and detect the particulate matter.
Furthermore, even when a disconnection occurs, when particulate matter is deposited so as to bridge the disconnection portion, a resistance path r _PMZ connected in parallel so as to bypass the disconnection portion is formed. There is also a possibility that the disconnection is not detected.
The present invention has been made to solve such a problem that may occur in the conventional particulate matter detection sensor 1z.

Here, with reference to FIG. 6A, FIG. 6B, and FIG. 6c, the manufacturing method of the detection part 10 which is the principal part of the particulate matter detection sensor 1 of this invention is demonstrated.
Insulating layer _{120, 8YSZ ((ZrO 2) 0.92} (Y 2 O 3) 0.08) consisting of partially stabilized zirconia, predetermined MgO, the insulating oxide material selected from one of _Al 2 _{O 3} By adding a binder, plasticizer, dispersant, solvent, etc., and using a known film formation method such as thick film printing or doctor blade method, the film is formed in a substantially flat shape with a film thickness of 5 μm or more and 20 μm or less. The insulating thin film sheet (120 _THN ) and the insulating thick film sheet (120 _THK ) formed in a substantially flat shape with a film thickness of 100 μm or more and 500 μm or less are formed.
In the following description, there is no particular distinction between the state of the green sheet before firing or the state of the sintered body after firing, but in the lamination step and the embedding step, the state of the green sheet It goes without saying that an integrated particulate matter detection element is formed by being processed and fired.

In the conductive sheet forming step, a conductive sheet for forming the first detection electrode EL _A and the second detection portion EL _B is formed.
The conductive _{sheet, LNF (LaNi 0.6 Fe 0.4 O} 3), LSN (La 1.2 Sr 0.8 NiO 4), LSM (La 1-X Sr X MnO 3-δ), LSC ( _{La 1-X Sr X CoO 3} -δ), LCC (La 1-X Ca X CrO 3-δ), LSCN (La 0.85 Sr 0.15 Cr 1-X Ni X O 3-δ) (0. A known binder blade method, press method, etc. by adding a predetermined binder, plasticizer, dispersant, solvent, etc. to a perovskite-type conductive oxide material selected from 1 ≦ X ≦ 0.7) In this method, a conductive thick film sheet (100 _THK ) formed in a substantially flat plate shape with a film thickness of 100 μm or more and 500 μm or less is used.
Described later, the thickness 5μm or more, the conductive thin film sheet _{100 THN} for implantation into 20μm or less of the insulating thin film sheet 120, using a conductive thick film sheet _{100 THK} the same material, an insulating thin film sheet _{120 THN} The same film thickness is formed.
A conductive sheet formed of a conductive oxide material such as LNF, LSN, LSM, LSC, LCC, or LSCN becomes a conductive oxide having a conductivity of 10 ⁻² S / cm or more by firing.
In the figure, the conductive sheet constituting the first detection electrode EL _A is identified by the symbol A, and the conductive sheet constituting the second detection electrode EL _B is identified by the symbol B. _Therefore , the code _| symbol which shows the difference between the electroconductive thick film sheet _100THK and the electroconductive thin film sheet _100THN is not attached _| subjected.

In the insulating sheet forming step, an insulating oxide material selected from partially stabilized zirconia, MgO, and Al ₂ O ₃ made of YSZ ((ZrO ₂ ) _0.92 (Y ₂ O ₃ ) _0.08 ) Is formed using a known molding method such as a doctor blade method or a thick film printing method.
The insulating sheet formed in the insulating sheet forming step becomes an insulating oxide having an electric conductivity of 10 ⁻⁵ S / cm or less, which constitutes the insulating layer 120, by firing.
The insulating thin film sheet 120 _THN that determines the distance between the detection electrodes is formed to have a film thickness of 5 μm or more and 20 μm or less, and the insulating thick film sheet 120 _THK embedded in the conductive thick film sheet 100 _THK described later is conductive. Thick film sheet 100 is formed to the same film thickness as _THK .
In the figure, the insulating thick film sheet 120 _THK and the insulating thin film sheet 120 _THN are made of the same material, and both of them become the insulating layer 120 after firing. Not.

The step-by-step illustrated insulating thick sheet embedded conductive thick film sheet forming process in FIG. 6A (a) ~ (d) , of the same thickness prepared in advance insulating thick film sheet 120 _THK and the conductive thick film sheet 100 superposed and _THK, using a mold M1, M2, by punching out at the same time, no gap embedded seen in the insulating film thickness sheet 120 conducting thick film sheet 100 in _THK the _THK, insulating thick sheet embedded A conductive thick film sheet (A layer, B layer) can be formed .
By appropriately changing the pattern of the mold, the insulating thick film sheet 120 _THK divided into a predetermined shape is embedded in a plurality of predetermined positions of the conductive thick film sheet 100 _THK , thereby the conductive thin film sheet embedded insulating thin film Sheets (MA layer, MB layer, C layer) can be formed .
The thickness 5μm or more, 20 [mu] m or less of the insulating thin film sheet ₁₂₀ partially same film conductive thin sheet embedding a conductive thin film sheet _{100 THN} was partitioned into a predetermined shape in the thickness buried insulating thin film sheet formed in a predetermined position of _THN In the process, when the above method is difficult, the conductive sheet and the insulating sheet having a predetermined pattern may be stacked to perform thick film printing.

The detection unit 10 is formed by laminating a sheet in which the insulating sheet 120 and the conductive sheet 100 are combined in a predetermined pattern through a laminating process as illustrated in FIG. 6B.
For example, in the case of the conductive thick film embedded in the insulating thick film sheet indicated as A layer in FIG. 6B, the insulating thick film sheet 120 _THK is embedded in five locations in the conductive thick film sheet 100 _THK , thereby returning the detection electrode. The lead portion 105A, the detection electrode facing portion 100A, the detection electrode lead portion 102B, and the detection electrode return lead portion 105B can be in a state of being disposed via the insulating layer 120.
In order to clarify whether it constitutes a first detection electrode EL _A part of the second detection electrode EL _B throat, for convenience, a side of the first detection electrode EL _A second detection Although the side of the electrode EL _B show separately hatching originally is a piece of conductive thick film sheet _{100 THK} by embedding an insulating thick film sheet _{120 THK.}
The conductive thick film sheet B layer embedded with the insulating thick film sheet is obtained by rotating the conductive thick film sheet A layer embedded with the insulating thick film sheet 180 degrees in the plane direction.

The conductive thin film sheet-embedded insulating thin film sheet MA layer connects the A layer and the A layer in series. By embedding the conductive thin film sheet 100 _THN in four predetermined locations of the insulating thin film sheet 120 _THN. The detection electrode return lead portion 105A, the detection electrode return portion 101A, the detection electrode lead portion 102B, and the detection electrode return lead portion 105B are arranged at predetermined positions in the insulating layer 120.
The conductive thin film sheet-embedded insulating thin film sheet MB layer connects the B layer and the B layer in series, and is obtained by rotating the conductive thin film sheet embedded insulating thin film sheet MA layer by 180 degrees in the plane direction. is there.

The conductive thin film sheet-embedded insulating thin film sheet C layer provides insulation between the first detection electrode facing portion 100A and the second detection electrode facing portion 100B facing each other, while the first detection electrode lead portion 102A and the second detection electrode facing portion 100B are insulated from each other . second detecting electrode lead part 102B, the first detection electrode return lead portions 105A, it is intended to reduce the conduction of the second detection electrode return lead part 105B, the conductive thin film in a predetermined four locations of the insulating thin film sheet _{120 THN} By embedding the sheet 100 _THN , the first detection electrode return lead portion 105A, the first detection electrode lead portion 102A, the second detection electrode lead portion 102B, and the second detection electrode are placed at predetermined positions in the insulating layer 120. The return lead portion 105B is disposed.
The first detection electrode EL is formed by repeatedly laminating a predetermined pattern such as A layer, MA layer, A layer, C layer, B layer, MB layer, B layer, C layer, A layer,. _a is at least a first detection electrode facing portion 100A which is a generally flat plate shape, a first detection electrode folded portion 101A, a part is bent in a substantially U-shaped, it is constituted by a detection electrode lead portion 102A is the first disconnection detecting terminal portion 103A at one end is formed, and the first PM detection terminal portion 104A is formed at the other end, to the PM detection terminal section 104A from the first disconnection detecting terminal portion 103A Can be formed in series, and the second detection electrode EL _B has at least a second detection electrode facing part 100B formed in a substantially flat plate shape, and a part of the second detection electrode EL _B is substantially a part. Second sensing electrode folded back in a U shape 101B and the detection electrode lead portion 102B, the second disconnection detection terminal portion 103B is formed at one end, the second PM detection terminal portion 104B is formed at the other end, and the second A single conduction path in which the disconnection detection terminal portion 103B to the PM detection terminal portion 104B are connected in series can be formed.

The conductive thick film sheet AE layer embedded in the insulating thick film sheet performs one end processing of the detection unit 10, and the conductive thick film sheet 120 _THK is embedded in three places of the conductive thick film sheet 100 _THK. The first detection electrode facing end portion 100AE is disposed so as to be connected to the first detection electrode folded portion 101A and the first detection electrode return lead portion 105A, and the second detection electrode facing end portion 100BE is disposed so as to be connected to the second detection electrode lead portion 102B and the second detection electrode return lead portion 105B.
Further, the upper terminal sheet ETP layer is composed only of the insulating sheet 120, and is intended to retain the insulation of one end face of the detection unit 10.

The conductive thin film sheet-embedded insulating thin film sheet C layer is repeatedly laminated so that the first detection electrode lead portion 102A, the second detection electrode lead portion 102B, the first detection electrode return lead portion 105A, the second The detection electrode return lead portion 105B can be formed to an arbitrary length.
Lower terminal sheet END layer is for performing other end processing of the detection unit 10, a conductive thick film sheet 100 _THK buried (reversed predetermined four locations of the insulative thick film sheet 120 _THK, conductive thick Insulating film thickness sheet 120 _THK may be embedded in predetermined three locations of film sheet 100 _THK .) , Thereby providing first disconnection detection terminal 103A, second disconnection detection terminal 103B, and first PM detection. terminal 104A, the second PM detection terminal 104B is formed, it is disposed on one side of the detector 10.

Further, in the actual manufacturing process, as is commonly used in the manufacturing method of multilayer ceramics, a frame portion that covers the periphery of each layer is provided, and after positioning holes are formed, the first precision is obtained with high accuracy . The detection electrode layer EL _A and the second detection electrode layer EL _B are opposed to each other with a certain gap while forming a conduction path connected in series without branching from one end to the other end. Can do.

In addition, in this embodiment, after forming the width | variety of each layer thickly and laminating | stacking, the several detection part 10 can be efficiently formed by cutting out to predetermined width | variety like Kintaro-an.
As shown in FIG. 6C, the detection unit aggregate 10MLT obtained in this way is cut into a predetermined thickness by using a cutting means such as a dicing saw to complete the detection unit 10.
If this is mounted on the substrate part 20 as shown in FIG. 3, the particulate matter detection element 2 which is the main part of the present invention is completed.

It should be noted that the individual pieces may be cut out from the detection unit assembly 10MLT before firing or after firing.
If it is processing before firing, there is a merit that the processing is easy because it is in the form of a molded body, but there is a demerit that dimensional variation of the detection unit 10 increases because there is a dimensional change due to firing.
If the processing is performed after firing, the strength of the detection unit 10 is high, so that there is a demerit that the processing becomes difficult. However, since there is no dimensional change due to firing, there is an advantage of high dimensional accuracy after processing.
Accordingly, it is possible to appropriately select at which time the processing should be performed depending on whether the production cost is important or the processing accuracy is important.

In addition, since the detection unit 10 which is a main part of the present invention has a laminated structure as described above, in the same way as a laminated structure such as a multilayer substrate or a piezoelectric actuator, impurities may be mixed during the processing step. There is a risk of delamination due to the difference in thermal expansion coefficient between the layers.
If delamination occurs in the first detection electrode EL _A or the second detection electrode EL _B , conduction between the respective layers may be inhibited and local disconnection may occur. According to the present invention, it is possible to detect the presence or absence of disconnection inside the device very easily.
Accordingly, the detection unit 10 is a laminate structure, by utilizing the stacking direction cross the detection surface, and the insulation distance between the first detection electrode EL _A and the second detection electrode EL _B very short Even when the dead mass is eliminated, high reliability can be maintained.

With reference to FIG. 7, a particulate matter detection sensor 1a according to a second embodiment of the present invention will be described. Since the same reference numerals are given to the same components as those in the above embodiment, detailed description thereof is omitted, and the same components but different parts are given the same reference characters with alphabets as branch numbers. The explanation will be focused on. The same applies to the following embodiments.
In the above embodiment, the heating element energization control circuit unit 32 that controls the energization of the heating element 220 provided in the substrate unit 20 is provided independently of the disconnection detection circuit unit 30 and the PM detection circuit unit 31. In this embodiment, the disconnection detection circuit unit 30 ( first disconnection detection circuit unit 301 Aa, second disconnection detection circuit unit 301 Ba) is used to detect the heat generation temperature of the heating element 220 and to control the temperature. The difference is that it is configured to be used for the above.

First detecting electrode internal resistance _{R A} and the first from the disconnection detection terminal 103A first up to the first PM detection terminal 104A of EL _A, a second disconnection detecting terminal of the second detection electrode EL _B second internal resistance _{R B} from 103B up to the second PM detection terminal 104B, in order to have a correlation to the temperature, from a first internal resistance _{R a} detected, first heating element 220 the heating temperature _{T 1} of the, it is possible to calculate the second heating temperature T ₂ of the heating element 220 from the second internal resistance _{R B.}
The obtained temperature result is fed back to the heater control circuit 320, and the heater control circuit 320 controls the driving of the driver 321 that opens and closes the switching element 322 that controls energization to the heating element 220 according to the temperature result. To do.
According to the present embodiment, in the same manner as the above-described embodiment, it is possible to detect the presence or absence of disconnection inside the detection unit 10 and to detect particulate matter with high accuracy. It becomes possible to control more accurately.

With reference to FIG. 8, a particulate matter detection sensor 1b according to a third embodiment of the present invention will be described.
In the above-described embodiment, in order to burn off particulate matter deposited on the detection unit 10 or improve detection accuracy by keeping the temperature at the time of detection constant, the heat generated by energization inside the substrate unit 20 is generated. an example is shown in which a body 220, in this embodiment, without having a heating element 220, the first detection electrode EL _a, and as each resistance heating element of the second detection electrode EL _B The difference is that it is configured to be used.
In the present embodiment, a first disconnection detecting circuit unit 301Ab for detecting disconnection across 103A-104A of the first detecting electrode EL _A, disconnection across 103B-104 B of the second detection electrode EL _B Each of the second disconnection detection circuit units 301Bb for detecting the heat is provided with a heat generation control function.
Specifically, the presence or absence of a disconnection is only detected by measuring the internal resistance between both ends 103A-104A of the first detection electrode EL _A and the internal resistance between both ends 103B-104A of the second EL _B. not, the resistance value of the conductor, since it has a temperature dependence, the temperature of the first detection electrode EL _a from the first detection resistance R _a measured, first from the second detection resistance value R _B The temperature of the second detection electrode EL _B is calculated.

Further, the heating value of the resistor is proportional to the power supply, the first detection resistance value R _A, while monitoring the second detection resistance value R _B, first detected from the first variable power source 32Ab the electrode EL _a, from the second variable power source 32Bb by increasing or decreasing the amount of power supplied to the second detection electrode EL _B, the first detection electrode _EL a, and the desired second detection electrode EL _B It becomes possible to maintain the temperature.
According to the present embodiment, in addition to the same effect as the above embodiment , when the particulate matter deposited on the first detection electrode EL _A and the second detection electrode EL _B is saturated, The power supplied from the first variable power source 32Ab and / or the second variable power source 32Bb is increased, and the temperature of the first detection electrode EL _A and / or the second detection electrode EL _B is increased and deposited. Particulate matter can also be removed by combustion.

With reference to FIG. 9A and FIG. 9B, the particulate matter detection sensor 1c and the detection electrode laminated body 10c which is the principal part in the 4th Embodiment of this invention are demonstrated.
In the above-described embodiment, the disconnection detection terminal portions 103A and 103B and the particulate matter detection terminal portion that are provided with the detection electrode return leads 105A and 105B so as to penetrate the inside of the detection electrode laminate 10 and are connected to the outside. The configuration in which 104A and 104B are pulled out to one end edge of the detection electrode laminate 10 has been described. However, as shown in FIGS. 9A and 9B, the disconnection detection terminal is not provided without providing the detection electrode return leads 105A and 105B. The parts 103Ac and 103Bc and the particulate matter detection terminal parts 104Ac and 104Bc are divided and exposed in four places, and the conductors 106Ac, 106Bc, 107Ac, 107Bc, 108Ac, 108Bc, 109Ac, 109Bc, 110Ac, provided on the surface of the substrate part 20c, 110Bc, 111Ac, and 111Bc wiring patterns Connection terminals 110Ac to achieve the connection, 110Bc, 111Ac, the point where the 111Bc to be disposed on the proximal side of the particulate matter detection device 2c differs.

Since the detection electrode return lead portions 105A and 105B are not formed, as shown in FIG. 9B, the configuration of each layer is simple and the manufacture is easier than the above embodiment.
In this embodiment, as in the above embodiment, the first detection electrode EL _A is without branching from the first disconnection detecting terminal 103Ac down to the first PM detection terminal 104Ac, single stroke-like conductive Since the path is formed and the second detection electrode EL _B is not branched from the second disconnection detection terminal 103Bc to the second PM detection terminal 104Bc, a one-stroke writing conductive path is formed . The presence or absence of a disconnection inside the first detection electrode EL _A and the second detection electrode EL _B can be detected very easily.

With reference to FIG. 10A and FIG. 10B, the particulate matter detection sensor 1d and the detection electrode laminate 10d in the fifth exemplary embodiment of the present invention will be described.
In the above embodiment, the conductive thick film sheet 100 _THK is embedded with the insulating thin film sheet 120 _THK, and the conductive thick film sheet embedded in the conductive thick film sheet (A layer, B layer), and the insulating thin film sheet 120 _THN. Conductive thin film sheet 100 _THN embedded conductive thin film sheet embedded insulating thin film sheets (MA layer, MB layer, C layer) are laminated in the first detection electrode folded portion 101A, second detection electrode The folded portion 101B, the first detection electrode lead portion 102A, and the second detection electrode lead portion 102B are formed, and the first detection electrode EL _A is connected to the first PM from the first disconnection detection terminal 103A. to the detection terminal 104A, the second detection electrode EL _B is a second disconnection detecting terminal 103B to the second PM detection terminal 104B, without branching, respectively, the series contact Although the method of forming the conductive paths, in the present embodiment, the first detection electrode folded portion 101A to secure the continuity of the layers, and the second detecting electrode folded portion 101B, the first detection electrode The difference is that the lead portion 102A and the second detection electrode lead portion 102B are formed by through-hole printing.

With this configuration, only the first detection electrode facing portion 100A and the first detection electrode facing portion 100B, which are partitioned in a substantially strip shape, are parallel to each other on the surface of the detection portion 10d via the insulating layer 120. The first detection electrode folded portion 101Ad, the second detection electrode folded portion 101Bd, the first detection electrode lead portion 102Ad, and the first detection electrode lead portion 102Bd are exposed in the insulating layer 120. It is buried inside.
Therefore, when an electric field is applied between the first detection electrode EL _Ad and the second detection electrode EL _Bd to collect particulate matter contained in the gas to be measured, the detection electrode is bent. without having to electric field concentration in a portion, the first detection electrode EL _Ad aligned parallel, since the uniform electric field is formed between the second detection electrode EL _Bd, particulate matter is trapped Can be suppressed and detection accuracy can be further improved.
Further, in the present invention, the directionality of the detection units 10, 10a, 10b, 10c, and 10d is not particularly limited, and is orthogonal to the longitudinal direction of the particulate matter detection element 2 as shown in FIG. 1B. The first detection electrode facing portion 100A and the second detection electrode facing portion 100B may be formed to be aligned in the direction, or as shown in FIG. 10A, with respect to the longitudinal direction of the particulate matter detection element 2 The first detection electrode facing portion 100A and the second detection electrode facing portion 100B may be formed to be aligned in the parallel direction.

In the above embodiment, the thickness of the insulating layer 120 that insulates between the pair of detection electrode facing portions 100A and 100B is 20 μm or less by making the detection portions 10, 10a, 10b, 10c, and 10d have a laminated structure. The configuration in which the detection accuracy is extremely high and the detection accuracy is extremely high has been described .
In the case of thick film printing, it is difficult to set the insulation distance for insulating the first detection electrode facing portion 100Az and the second detection electrode facing portion 100Bz to 20 μm or less. A decline is inevitable .

DESCRIPTION OF SYMBOLS 1 Particulate matter detection sensor 10 Detection part 100A 1st detection electrode opposing part
100B 2nd detection electrode opposing part 101A 1st detection electrode return part
101B second detection electrode folded portion 102A first detection electrode lead portion
102B second detection electrode lead portion 103A first disconnection detection terminal portion 103B second disconnection detection terminal portion 104A first particulate matter detection terminal portion 104B second particulate matter detection terminal portion 105A first detection electrode Return lead part 105B Second detection electrode Return lead part 2 Particulate matter detection element 20 Substrate part 200, 210 Insulating substrate 220 Heating element 221A, 221B Heating element lead part 222A, 222B Heating element terminal part 223A, 223B Through-hole electrode
A layer, B layer Insulating thick film sheet embedded conductive thick film sheet
MA layer, MB layer, C layer Conductive thin film sheet embedded insulating thin film sheet

JP 2005-164554 A JP 2012-47596 A JP 2011-203093 A

Claims (10)

Particulate matter trapped and accumulated in at least a first detection electrode (EL _A) and a second detection electrode facing at a predetermined distance _(EL B) a detection section having a (10,10c, 10d) The electrical characteristics between the first detection electrode (EL _A ) and the second detection electrode (EL _B ), which change according to the amount of the gas, are detected to detect the particulate matter contained in the gas to be measured. A particulate matter detection sensor provided with a particulate matter detection element (2, 2, 2b, 2c, 2d) for detecting an amount,
The first detection electrode (EL _A ) forms a conduction path connected in series from one end (103A, 103Ac, 103Ad) to the other end (104A, 104Ac, 104Ad). While
In the detection part (10, 10c, 10d), a folded part (101A, 101Ad) in which a part thereof is bent in a U-shape;
A detection electrode facing portion (100A) facing the other detection electrode via an insulating layer (120) that forms a predetermined distance between the detection electrodes,
The second detection electrode (EL _B ) forms a conduction path connected in series from one end (103B, 103Bc, 103Bd) to the other end (104B, 104Bc, 104Bd). While
In the detection part (10, 10c, 10d), a folded part (101B, 101Bd) in which a part thereof is bent in an inverted U shape,
A detection electrode facing portion (100B) facing the other detection electrode via an insulating layer (120) that forms a predetermined distance between the detection electrode pairs ,
Said one end of the first detection electrode _{(EL A) (103A, 103Ac} , 103Ad) the other end portion from (104A, 104Ac, 104Ad) by the measurement of the resistance value of up to, the first _A first disconnection detection circuit section (301A , 301Aa, 301Ab) for detecting the presence or absence of disconnection inside the detection electrode (EL _A ) ;
By measuring the resistance value from the one end (103B, 103Bc, 103Bd) to the other end (104B, 104Bc, 104Bd) of the second detection electrode (EL _B ) , A particulate matter detection sensor (1, 1a, 1b ) comprising a second breakage detection circuit portion (301B, 301Ba, 301Bb) for detecting the presence or absence of a breakage in the detection electrode (EL _B ) . 1c, 1d). Between one end (103A, 103Ac, 103Ad) of the first detection electrode (EL _A ) and one end (103B, 103Bc, 103Bd) of the second detection electrode (EL _B ) (103A -103B, 103Ac-103Bc, 103Ad-103Bd), or the other end (104A, 104Ac, 104Ad) of the first detection electrode (EL _A ) and the other of the second detection electrode (EL _B ) The first detection electrode (EL _A) is detected by detecting any one of the resistance value, capacitance, and impedance between the short portions (104B, 104Bc, 104Bd) (104A-104B, 104Ac-104Bc, 104Ad-104Bd). ) and to include a PM detection circuit (31) for detecting the deposition amount of the particulate matter deposited between the second detection electrode (EL _B) The particulate matter detection sensor as claimed in claim 1 (1,1a, 1b, 1c, 1d). The particulate matter detection element (2, 2b, 2c, 2d)
The detection unit (10, 10c, 10d);
The board portion (20, 20b, 20c, 20d) on which this is mounted,
The detection unit (10, 10c, 10d)
The first detection electrode facing portion (100A ) and the second detection electrode facing portion ( 100B) formed in a substantially flat plate shape with a film thickness of 100 μm or more and 500 μm or less,
The particulate matter detection sensor according to claim 1 or 2, comprising a cross-section in the stacking direction of a stacked structure in which the insulating layer (120) formed in a substantially flat shape with a film thickness of 5 µm to 20 µm is repeatedly stacked. (1, 1a, 1b, 1c, 1d). The particulate matter detection element (2, 2b, 2c, 2d)
The particulate matter detection sensor (1, 1a, 1b, 1c, 1d) according to any one of claims 1 to 3, comprising a resistance heating element (EL _A , EL _B / 220) that generates heat when energized. The first disconnection detection circuit section (301Aa ) is
The presence or absence of breakage by measuring the DC resistance of the first detector from the one end of the (EL _A) (103A) to the first detector the other end of the (EL _A) (104A) And detecting
The second disconnection detection circuit section (301Ba)
The presence or absence of breakage by measuring the DC resistance of the second detector from the one end of the (EL _B) (103B) to the second detector the other end of the (EL _B) (104B) Detect
The heat generation temperature of the heating element (EL _A , EL _B / 220) is calculated from the DC resistance value detected by the first disconnection detection circuit unit (301Aa) and the second disconnection detection circuit unit (301Ba). The particulate matter detection sensor (1a, 1b) according to claim 4, wherein the particulate matter detection sensor (1a, 1b) has a function as a heat generation control circuit unit for controlling energization to the resistance heating element (EL _A , EL _B / 220). The substrate part (20) is
The particulate matter detection sensor (1, 1a, 1c, 1d) according to claim 4, comprising a substantially flat insulating substrate (200, 210) and the resistance heating element (220) therein. The first disconnection detecting circuit unit (301Ab) is, one end portion of the first detection electrode (EL _A) the other end of the from (103A) a first detection electrode (EL _A) (104A) Measure the DC resistance up to and detect the disconnection ,
Said second disconnection detecting circuit unit (301Bb) is, one end of the second detection electrode (EL _B) the other end of the from (103B) a second detection electrode (EL _B) (104B) Measure the direct current resistance to detect the presence or absence of disconnection ,
Using each of the first detection electrode (EL _A ) and the second detection electrode (EL _B ) as the resistance heating element,
In the first detection electrode (EL _A ), the first detection electrode (EL _A ) generates heat by energization between the one end (103A ) and the other end (104A ). ,
In the second detection electrode (EL _B ), the second detection electrode (EL _B ) generates heat by energization between the one end (103B) and the other end (104B) . The particulate matter detection sensor (1b) according to claim 4, further comprising a heat generation control circuit unit. The first detection electrode and the (EL _A) and the second detection electrode _(EL B) _{but, LNF (LaNi 0.6 Fe 0.4 O} 3), LSN (La 1.2 Sr 0.8 NiO 4 _{), LSM (La 1-X} Sr X MnO 3-δ), LSC (La 1-X Sr X CoO 3-δ), LCC (La 1-X Ca X CrO 3-δ), LSCN (La 0.85 Sr _0.15 Cr _1-X Ni _X O _3-δ ) (0.1 ≦ X ≦ 0.7), and a perovskite-type conductive oxide material having a conductivity of 10 ⁻² S The particulate matter detection sensor (1, 1a, 1b, 1c, 1d) according to any one of claims 1 to 7, which is a conductive oxide of at least / cm. The insulating layer (120) _{is, 8YSZ ((ZrO 2) 0.92} (Y 2 O 3) 0.08) part consisting of stabilized zirconia, MgO, insulating oxide selected from one of _Al 2 _{O 3} The particulate matter detection sensor (1, 1a, 1b, 1c, 1d) according to any one of claims 1 to 7, which is an insulating oxide made of a material and having an electrical conductivity of 10 ^-5 S / cm or less. The cross section of the laminated structure in which the conductive sheet formed to a predetermined film thickness and the insulating sheet formed to the predetermined film thickness are laminated is determined by the film thickness of the insulating sheet as a detection unit (10, 10c, 10d). Electrical characteristics that change according to the amount of particulate matter deposited between the first detection electrode (EL _A ) and the second detection electrode (EL _B ) opposed to each other with a predetermined gap therebetween The particulate matter detection element (2, 1) used for the particulate matter detection sensor (1, 1a, 1b, 1c, 1d) according to any one of claims 1 to 9, wherein particulate matter in the gas to be measured is detected by 2b, 2c, 2d),
at least,
LNF (LaNi _0.6 Fe _0.4 O ₃ ), LSN (La _1.2 Sr _0.8 NiO ₄ ), LSM (La _1-X Sr _X MnO _3-δ ), LSC (La _1-X Sr _X CoO _3−δ ), LCC (La _1−X Ca _X CrO _3−δ ), LSCN (La _0.85 Sr _0.15 Cr _1−X Ni _X O _3−δ ) (0.1 ≦ X ≦ 0. 7) Using the perovskite-type conductive oxide material selected from any one of 7), the substantially flat plate-like first detection electrode facing portion (100A ) having the thickness of 100 μm or more and 500 μm or less and the second detection A conductive thick film sheet forming step of forming a conductive thick film sheet (100 _THK ) for constituting the electrode facing portion ( 100B);
Conductive thin film for forming the first detection electrode folded portion (101A) and the second detection electrode folded portion (101B) having a film thickness of 5 μm or more and 10 μm or less using the conductive oxide material A conductive thin film sheet forming step for forming a sheet (100 _THN );
_{8YSZ ((ZrO 2) 0.92 (} Y 2 O 3) 0.08) partially stabilized zirconia consisting of, MgO, using an insulating oxide material selected from one of _Al 2 _{O 3, 20μm} or more 5μm a substantially flat insulating layer _{(120 THN)} insulating sheet film forming step of forming a for configuring the insulating thin sheet _{(120 THN)} a having a thickness of less,
Insulating sheet thick film for forming an insulating thick film sheet (120 _THK ) for forming a substantially flat insulating layer (120 _THK ) having a film thickness of 100 μm or more and 500 μm or less using the insulating oxide material Molding process;
Insulation of the same material as the insulating thin film sheet (120 _THN ) formed in the same thickness as the conductive thick film sheet and partitioned into a predetermined shape at a predetermined position in the conductive thick film sheet (100 _THK ) Insulating thick film sheet embedding conductive thick film (A layer / B layer) embedding a thick film sheet (120 _THK );
A conductive thin film sheet (100 _THK ) of the same material as the conductive thin film sheet (100 _THK ) formed in the same thickness as the insulating thin film sheet and partitioned in a predetermined shape at a predetermined position in the insulating thin film sheet (120 _THN ) 100 _THN ), a conductive thin film sheet embedded insulating thin film sheet (MA layer / MB layer / C layer) molding step,
The obtained insulating thick film sheet embedded conductive thick film sheet (A layer / B layer) and conductive thin film sheet embedded insulating thin film sheet (MA layer / MB layer / C layer) were laminated in a predetermined repeating pattern. And a laminating step for forming the detection units (10, 10c, 10d) ,
The first detection electrode folded portion (101A) in which a part of the first detection electrode (EL _A ) is bent in a U shape in the detection unit, and a part of the second detection electrode (EL _B ) The method for manufacturing a particulate matter detection element, wherein the folded portion (101B) bent in an inverted U shape is formed in the detection portion.

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