JP6867178B2

JP6867178B2 - Plasma reactor

Info

Publication number: JP6867178B2
Application number: JP2017015965A
Authority: JP
Inventors: 慎介和田; 一哉内藤; 谷口　昌司; 昌司谷口; 和彦間所; 伸介伊藤; 史和河尻; 茂仁坂井
Original assignee: Daihatsu Motor Co Ltd
Current assignee: Daihatsu Motor Co Ltd
Priority date: 2017-01-31
Filing date: 2017-01-31
Publication date: 2021-04-28
Anticipated expiration: 2037-01-31
Also published as: JP2018122238A

Description

本発明は、プラズマリアクタに関し、とくに、エンジンから排出される排ガスの浄化に用いられるプラズマリアクタに関する。 The present invention relates to a plasma reactor, and more particularly to a plasma reactor used for purifying exhaust gas emitted from an engine.

エンジン、とくにディーゼルエンジンから排出される排ガスには、ＣＯ（一酸化炭素）、ＨＣ（炭化水素）、ＮＯｘ（窒素酸化物）およびＰＭ（Particulate Matter：粒子状物質）などが含まれる。 Exhaust gas emitted from an engine, particularly a diesel engine, includes CO (carbon monoxide), HC (hydrocarbon), NOx (nitrogen oxide), PM (Particulate Matter) and the like.

排ガスに含まれるＰＭを除去する手法として、プラズマリアクタを用いて、排ガスに含まれるＰＭを除去する手法が提案されている。プラズマリアクタは、複数の電極パネルを備えている。電極パネルは、たとえば、誘電体に電極を内蔵した構成であり、複数の電極パネルは、排ガスの流れ方向と直交する方向に間隔を空けて積層される。互いに対向する電極間に電圧が印加されると、誘電体バリア放電が生じて、電極パネル間に低温プラズマ（非平衡プラズマ）が発生し、電極パネル間を流れる排ガス中のＰＭが酸化により除去される。 As a method for removing PM contained in exhaust gas, a method for removing PM contained in exhaust gas has been proposed by using a plasma reactor. The plasma reactor includes a plurality of electrode panels. The electrode panel has, for example, a configuration in which electrodes are built in a dielectric, and a plurality of electrode panels are laminated at intervals in a direction orthogonal to the flow direction of exhaust gas. When a voltage is applied between the electrodes facing each other, a dielectric barrier discharge occurs, low-temperature plasma (non-equilibrium plasma) is generated between the electrode panels, and PM in the exhaust gas flowing between the electrode panels is removed by oxidation. To.

特開２００７−１６０２６５号公報JP-A-2007-160265

図７に示されるように、電極パネル９１の誘電体９２には、電極９３を内蔵する放電部９４に対して排ガスの流れ方向および電極パネル９１の積層方向の両方向と直交する方向の両側に、一方面が放電部９４よりも一段高い非放電部９５が形成されている。 As shown in FIG. 7, the dielectric 92 of the electrode panel 91 has a direction orthogonal to both the flow direction of the exhaust gas and the stacking direction of the electrode panel 91 with respect to the discharge portion 94 containing the electrode 93. A non-discharged portion 95 having one surface higher than the discharged portion 94 is formed.

非放電部９５の一方面および他方面には、メタライズにより、それぞれ金属膜からなる表面端子９６，９７が形成されている。また、非放電部９５には、その一方面上の表面端子９６と他方面上の表面端子９７とを導通させる電気導通部９８が形成されている。たとえば、表面端子９６，９７および電気導通部９８は、互いに間隔を空けた２つの部位に形成されており、積層方向の一方側から奇数番目の電極パネル９１では、一方の部位の電気導通部９８が電極９３と導通し、偶数番目の電極パネル９１では、他方の部位の電気導通部９８が電極９３と導通している。 Surface terminals 96 and 97 made of a metal film are formed on one surface and the other surface of the non-discharging portion 95 by metallizing, respectively. Further, the non-discharging portion 95 is formed with an electrically conductive portion 98 that conducts the surface terminal 96 on one surface and the surface terminal 97 on the other surface. For example, the surface terminals 96 and 97 and the electrically conductive portion 98 are formed at two portions spaced apart from each other, and in the electrode panel 91 which is an odd number from one side in the stacking direction, the electrically conductive portion 98 of one portion is formed. Is conducting with the electrode 93, and in the even-numbered electrode panel 91, the electrically conducting portion 98 at the other portion is conducting with the electrode 93.

電極パネル９１が積層された状態において、上側の電極パネル９１の表面端子９７と下側の電極パネル９１の表面端子９６とが重ね合わされることにより、上下の電極パネル９１間での導通が確保される。そして、一方の部位の表面端子９６，９７および電気導通部９８をプラス端子とし、他方の部位の表面端子９６，９７および電気導通部９８をマイナス端子として、プラス端子とマイナス端子との間に電圧が印加されることにより、互いに対向する電極間に電圧を印加することができる。 In the state where the electrode panels 91 are laminated, the surface terminals 97 of the upper electrode panel 91 and the surface terminals 96 of the lower electrode panel 91 are overlapped with each other, so that continuity between the upper and lower electrode panels 91 is ensured. To. Then, the surface terminals 96 and 97 and the electrically conductive portion 98 of one portion are used as positive terminals, and the surface terminals 96 and 97 and the electrically conductive portion 98 of the other portion are used as negative terminals, and a voltage is applied between the positive terminal and the negative terminal. Is applied, so that a voltage can be applied between the electrodes facing each other.

しかしながら、メタライズにより形成される表面端子９６，９７が１０μｍ程度の厚みを有しているため、上下の電極パネル９１の非放電部９５間に隙間が生じてしまう。この隙間にＰＭが入り込んで堆積すると、堆積したＰＭが導通媒体となって、プラス端子とマイナス端子との間の絶縁抵抗が低下することにより、放電特性が変化し、ＰＭ除去性能が安定しなくなるおそれがある。また、最悪の場合には、プラス−マイナス端子間がショートし、電源故障等の不具合を誘発するおそれがある。 However, since the surface terminals 96 and 97 formed by metallizing have a thickness of about 10 μm, a gap is generated between the non-discharged portions 95 of the upper and lower electrode panels 91. When PM enters and accumulates in this gap, the accumulated PM becomes a conductive medium and the insulation resistance between the positive terminal and the negative terminal decreases, so that the discharge characteristics change and the PM removal performance becomes unstable. There is a risk. Further, in the worst case, a short circuit between the plus and minus terminals may cause a trouble such as a power failure.

本発明の目的は、プラス端子とマイナス端子との間の絶縁抵抗の低下を抑制できる、プラズマリアクタを提供することである。 An object of the present invention is to provide a plasma reactor capable of suppressing a decrease in insulation resistance between a positive terminal and a negative terminal.

前記の目的を達成するため、本発明に係るプラズマリアクタは、エンジンから排出される排ガスの浄化に用いられるプラズマリアクタであって、排ガスの流通方向と直交する積層方向に積層される複数の電極パネルを含み、電極パネルは、誘電体および電極を備え、誘電体は、電極が内蔵される平板状の放電部と、放電部に対して流通方向および積層方向の両方向に直交する方向の両側に形成され、放電部よりも大きな厚みの非放電部とを有し、非放電部の積層方向の一方面には、当該一方面から一段凹ませた凹部が形成され、凹部の底面には、第１表面端子が設けられ、非放電部の積層方向の他方面には、当該他方面に対向する非放電部に形成されている凹部に嵌まる第２表面端子が設けられ、非放電部には、第１表面端子と第２表面端子とを導通させる（電気的に接続する）電気導通部が設けられており、凹部内に、凹部内で第１表面端子と第２表面端子とに挟まれて圧縮変形する導電性の弾性体が設けられる。 In order to achieve the above object, the plasma reactor according to the present invention is a plasma reactor used for purifying the exhaust gas discharged from the engine, and a plurality of electrode panels are laminated in a stacking direction orthogonal to the flow direction of the exhaust gas. The electrode panel includes a dielectric and an electrode, and the dielectric is formed on both sides of a flat plate-shaped discharge portion in which the electrode is built and a direction orthogonal to both the flow direction and the stacking direction with respect to the discharge portion. It has a non-discharged portion having a thickness larger than that of the discharged portion, and a recess is formed on one surface of the non-discharging portion in the stacking direction in a step recessed from the one surface, and a first recess is formed on the bottom surface of the recess. A surface terminal is provided, and a second surface terminal that fits into a recess formed in the non-discharged portion facing the other surface is provided on the other surface of the non-discharged portion in the stacking direction, and the non-discharged portion is provided with a second surface terminal. An electrically conductive portion that conducts (electrically connects) the first surface terminal and the second surface terminal is provided, and is sandwiched between the first surface terminal and the second surface terminal in the recess. A conductive elastic body that undergoes compression deformation is provided.

この構成によれば、複数の電極パネルが排ガスの流通方向と直交する方向に積層されている。各電極パネルは、誘電体に電極を内蔵した構成を有している。誘電体は、電極が内蔵される平板状の放電部と、放電部の両側に放電部よりも大きな厚みの非放電部とを有している。そのため、複数の電極パネルの放電部間には、放電部と非放電部との厚さの差による間隔が生じる。互いに対向する電極間に電圧が印加されると、誘電体バリア放電が生じて、放電部間にプラズマが発生し、放電部間を流れる排ガスに含まれるＰＭがプラズマの酸化作用により除去される。 According to this configuration, a plurality of electrode panels are laminated in a direction orthogonal to the flow direction of the exhaust gas. Each electrode panel has a structure in which an electrode is built in a dielectric. The dielectric has a flat plate-shaped discharge portion in which an electrode is built, and a non-discharge portion having a thickness larger than that of the discharge portion on both sides of the discharge portion. Therefore, a space is generated between the discharged parts of the plurality of electrode panels due to the difference in thickness between the discharged part and the non-discharged part. When a voltage is applied between the electrodes facing each other, a dielectric barrier discharge occurs, plasma is generated between the discharge portions, and PM contained in the exhaust gas flowing between the discharge portions is removed by the oxidizing action of the plasma.

非放電部の一方面には、凹部が形成され、凹部の底面には、第１表面端子が設けられている。非放電部の他方面には、その他方面に対向する非放電部に形成されている凹部に嵌まるように第２表面端子が設けられている。また、非放電部には、第１表面端子と第２表面端子とを導通させる電気導通部が設けられている。そして、凹部内には、導電性の弾性体が設けられ、その弾性体が第１表面端子と第２表面端子との間に挟まれて圧縮変形することにより、上下の電極パネル間で第１表面端子と第２表面端子とが導通する。 A recess is formed on one surface of the non-discharging portion, and a first surface terminal is provided on the bottom surface of the recess. On the other surface of the non-discharging portion, a second surface terminal is provided so as to fit into a recess formed in the non-discharging portion facing the other direction. Further, the non-discharging portion is provided with an electrically conductive portion that conducts the first surface terminal and the second surface terminal. Then, a conductive elastic body is provided in the recess, and the elastic body is sandwiched between the first surface terminal and the second surface terminal and is compressed and deformed, so that the first is formed between the upper and lower electrode panels. The surface terminal and the second surface terminal are electrically connected.

上下の電極パネルにおいて、一方の電極パネルの第２表面端子が他方の電極パネルの凹部に嵌まるので、一方の電極パネルの非放電部の他方面と他方の電極パネルの非放電部の一方面とを密着させることができる。そのため、上下の電極パネルの非放電部間にＰＭが入ることを抑制できる。 In the upper and lower electrode panels, since the second surface terminal of one electrode panel fits into the recess of the other electrode panel, the other surface of the non-discharged portion of one electrode panel and one surface of the non-discharged portion of the other electrode panel. Can be brought into close contact with. Therefore, it is possible to suppress PM from entering between the non-discharging portions of the upper and lower electrode panels.

よって、非放電部における互いに間隔を空けた２つの部位に第１表面端子、第２表面端子および電気導通部が設けられて、一方の部位の第１表面端子、第２表面端子および電気導通部がプラス端子とされ、他方の部位の第１表面端子、第２表面端子および電気導通部がマイナス端子とされる構成において、プラス端子とマイナス端子との間にＰＭによる導電パスが形成されることを抑制でき、プラス端子とマイナス端子との間の絶縁抵抗の低下を抑制できる。その結果、正常な放電を維持でき、端子間ショートによる電源の故障を防止できる。 Therefore, the first surface terminal, the second surface terminal, and the electrically conducting portion are provided at two portions of the non-discharging portion that are spaced apart from each other, and the first surface terminal, the second surface terminal, and the electrically conducting portion of one portion are provided. Is a positive terminal, and a conductive path by PM is formed between the positive terminal and the negative terminal in a configuration in which the first surface terminal, the second surface terminal, and the electrically conductive portion of the other portion are negative terminals. Can be suppressed, and a decrease in insulation resistance between the positive terminal and the negative terminal can be suppressed. As a result, normal discharge can be maintained, and failure of the power supply due to a short circuit between terminals can be prevented.

本発明によれば、プラス端子とマイナス端子との間の絶縁抵抗の低下を抑制でき、正常な放電を維持でき、端子間ショートによる電源の故障を防止できる。 According to the present invention, it is possible to suppress a decrease in the insulation resistance between the positive terminal and the negative terminal, maintain a normal discharge, and prevent a power failure due to a short circuit between the terminals.

プラズマリアクタの構成を図解的に示す断面図である。It is sectional drawing which shows the structure of a plasma reactor graphically. 電極パネルの積層体の斜視図である。It is a perspective view of the laminated body of an electrode panel. 図２に示される切断面線Ａ−Ａにおける電極パネルの積層体の図解的な断面図である。It is a schematic sectional view of the laminated body of the electrode panel in the cut plane line AA shown in FIG. 図２に示される切断面線Ｂ−Ｂにおける電極パネルの積層体の図解的な断面図である。It is a schematic sectional view of the laminated body of the electrode panel in the cut plane line BB shown in FIG. 電極パネルの他の構成を示す斜視図である。It is a perspective view which shows the other structure of an electrode panel. 図５に示される構成の電極パネルの積層体の図解的な断面図である。FIG. 5 is a schematic cross-sectional view of a laminated body of electrode panels having the configuration shown in FIG. 本願発明者らが先行して開発したプラズマリアクタの構成を図解的に示す断面図である。It is sectional drawing which graphically shows the structure of the plasma reactor which the inventors of this application developed in advance.

以下では、本発明の実施の形態について、添付図面を参照しつつ詳細に説明する。 Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

＜プラズマリアクタ＞
図１は、プラズマリアクタ１の構成を図解的に示す断面図である。 <Plasma reactor>
FIG. 1 is a cross-sectional view schematically showing the configuration of the plasma reactor 1.

プラズマリアクタ１は、車両のエンジン（図示せず）から排出される排ガスからＰＭ（Particulate Matter：粒子状物質）を除去して、排ガスを浄化するために、たとえば、エキゾーストパイプなどの排気管２の途中部に介装される。プラズマリアクタ１は、リアクタボディ（ケース）３と、リアクタボディ３内に収容された複数の電極パネル４とを備えている。 The plasma reactor 1 removes PM (Particulate Matter) from the exhaust gas discharged from the vehicle engine (not shown) to purify the exhaust gas, for example, in an exhaust pipe 2 such as an exhaust pipe. It is intervened in the middle. The plasma reactor 1 includes a reactor body (case) 3 and a plurality of electrode panels 4 housed in the reactor body 3.

リアクタボディ３は、金属製であり、筒状（管状）に形成されている。リアクタボディ３の一方の開口は、排ガスを流入させる流入口１１であり、他方の開口は、排ガスを流出させる流出口１２である。エンジンから排気管２に排出される排ガスは、排気管２を流通する途中で、流入口１１からリアクタボディ３内に流入して、リアクタボディ３内を流通し、流出口１２から流出する。 The reactor body 3 is made of metal and is formed in a tubular shape (tubular shape). One opening of the reactor body 3 is an inflow port 11 through which the exhaust gas flows in, and the other opening is an outflow port 12 through which the exhaust gas flows out. The exhaust gas discharged from the engine to the exhaust pipe 2 flows into the reactor body 3 from the inflow port 11 while flowing through the exhaust pipe 2, flows through the reactor body 3, and flows out from the outflow port 12.

電極パネル４は、誘電体からなる矩形平板状の誘電体平板２１に内蔵電極２２が厚さ方向に挟み込まれた構成を有している。言い換えれば、電極パネル４は、誘電体からなる平板状の誘電体平板２１を厚さ方向に２分割した各分割部分で内蔵電極２２をその両面から挟み込んだ構成を有している。誘電体平板２１の材料である誘電体としては、Ａｌ２Ｏ３（アルミナ）を例示することができる。内蔵電極２２の材料としては、タングステンを例示することができる。内蔵電極２２は、たとえば、縦方向に延びる複数の線状部および縦方向と直交する横方向に延びる複数の線状部からなる格子状をなし、四角形状の網目を多数有している。 The electrode panel 4 has a structure in which a built-in electrode 22 is sandwiched in a rectangular flat plate-shaped dielectric flat plate 21 made of a dielectric material in the thickness direction. In other words, the electrode panel 4 has a configuration in which the built-in electrode 22 is sandwiched from both sides of each divided portion of the flat plate-shaped dielectric flat plate 21 made of a dielectric material divided into two in the thickness direction. As the dielectric material of the dielectric flat plate 21, Al2O3 (alumina) can be exemplified. Tungsten can be exemplified as the material of the built-in electrode 22. The built-in electrode 22 has, for example, a grid shape including a plurality of linear portions extending in the vertical direction and a plurality of linear portions extending in the horizontal direction orthogonal to the vertical direction, and has a large number of quadrangular meshes.

複数の電極パネル４は、排ガスの流通方向と直交する積層方向に積層されることにより積層体（以下、「電極パネル積層体」という。）を構成している。 The plurality of electrode panels 4 are laminated in a stacking direction orthogonal to the flow direction of the exhaust gas to form a laminated body (hereinafter, referred to as "electrode panel laminated body").

＜電極パネル積層体＞
図２は、電極パネル積層体の斜視図である。図３は、図２に示される切断面線Ａ−Ａにおける電極パネル積層体の図解的な断面図である。図４は、図２に示される切断面線Ｂ−Ｂにおける電極パネル積層体の図解的な断面図である。 <Electrode panel laminate>
FIG. 2 is a perspective view of the electrode panel laminated body. FIG. 3 is a schematic cross-sectional view of the electrode panel laminate at the cut plane line AA shown in FIG. FIG. 4 is a schematic cross-sectional view of the electrode panel laminate at the cut plane line BB shown in FIG.

誘電体平板２１は、内蔵電極が内蔵される矩形平板状の放電部３１を排ガスの流通方向（以下、単に「流通方向」という。）および電極パネル４の積層方向（以下、単に「積層方向」という。）の両方向と直交する幅方向の中央部に有し、その放電部３１に対して幅方向の両側に放電部３１よりも大きな厚みの非放電部３２を有している。非放電部３２の一方面３３は、放電部３１の一方面３４よりも一段高く形成され、放電部３１の一方面３４と非放電部３２の一方面３３との間には、段差が生じている。非放電部３２の他方面３５は、放電部３１の他方面３６と面一に形成されている。 In the dielectric flat plate 21, the rectangular flat plate-shaped discharge portion 31 in which the built-in electrode is built is referred to as the exhaust gas flow direction (hereinafter, simply referred to as “flow direction”) and the electrode panel 4 stacking direction (hereinafter, simply “stacking direction”). It is provided in the central portion in the width direction orthogonal to both directions, and has non-discharge portions 32 having a thickness larger than that of the discharge portion 31 on both sides in the width direction with respect to the discharge portion 31. The one surface 33 of the non-discharging portion 32 is formed one step higher than the one surface 34 of the discharging portion 31, and a step is generated between the one surface 34 of the discharging portion 31 and the one surface 33 of the non-discharging portion 32. There is. The other surface 35 of the non-discharging portion 32 is formed flush with the other surface 36 of the discharging portion 31.

各非放電部３２の一方面３３には、流通方向に互いに離れた２つの部位のそれぞれに、矩形状の凹部４１が形成されている。凹部４１の深さは、たとえば、放電部３１の一方面３４と非放電部３２の一方面３３との間の段差とほぼ同じである。この段差とほぼ同じ深さの凹部４１は、たとえば、誘電体平板２１と同じ外形および放電部３１と同じ厚みを有する誘電体からなる平板の幅方向の両端部上に、非放電部３２と同じ外形および放電部３１の一方面３４と非放電部３２の一方面３３との間の段差と同じ厚みを有し、かつ、凹部４１に対応する開口がパンチング加工などの打ち抜き加工により形成された誘電体からなる平板を重ね合わせて、それらを焼成することにより形成することができる。 On one surface 33 of each non-discharging portion 32, a rectangular recess 41 is formed in each of two portions separated from each other in the distribution direction. The depth of the recess 41 is, for example, substantially the same as the step between the one surface 34 of the discharging portion 31 and the one surface 33 of the non-discharging portion 32. The recess 41 having substantially the same depth as the step is, for example, on both ends in the width direction of a dielectric made of a dielectric having the same outer shape as the dielectric flat plate 21 and the same thickness as the discharge portion 31, and is the same as the non-discharge portion 32. Dielectric having the same thickness as the step between the outer shape and one surface 34 of the discharge portion 31 and the one surface 33 of the non-discharge portion 32, and the opening corresponding to the recess 41 formed by punching or other punching. It can be formed by stacking flat plates made of bodies and firing them.

各凹部４１の底面には、図３および図４に示されるように、金属膜からなる第１表面端子４２が設けられている。また、非放電部３２の他方面３５には、各第１表面端子４２と積層方向に重なる位置に、第１表面端子４２と同じ形状の金属膜からなる第２表面端子４３が設けられている。さらに、非放電部３２には、第１表面端子４２と第２表面端子４３とを導通させる金属製の電気導通部４４が凹部４１の底面と他方面３５との間を貫通して設けられている。第１表面端子４２、第２表面端子４３および電気導通部４４は、たとえば、メタライズにより形成される。 As shown in FIGS. 3 and 4, a first surface terminal 42 made of a metal film is provided on the bottom surface of each recess 41. Further, on the other surface 35 of the non-discharging portion 32, a second surface terminal 43 made of a metal film having the same shape as the first surface terminal 42 is provided at a position overlapping with each first surface terminal 42 in the stacking direction. .. Further, the non-discharging portion 32 is provided with a metal electrically conductive portion 44 that conducts the first surface terminal 42 and the second surface terminal 43 so as to penetrate between the bottom surface of the recess 41 and the other surface 35. There is. The first surface terminal 42, the second surface terminal 43, and the electrically conductive portion 44 are formed by, for example, metallizing.

そして、各凹部４１内には、金属薄板を屈曲させることにより形成された板ばね４５が設けられている。板ばね４５には、耐熱性が求められるため、その材料としては、たとえば、インコネル（登録商標）などのニッケル基の超合金が挙げられる。 A leaf spring 45 formed by bending a thin metal plate is provided in each recess 41. Since the leaf spring 45 is required to have heat resistance, examples of the material thereof include nickel-based superalloys such as Inconel (registered trademark).

電極パネル積層体の互いに対向する２個の電極パネル４において、積層方向の一方側（上側）の電極パネル４の第２表面端子４３が積層方向の他方側（下側）の電極パネル４の凹部４１に嵌まる。そして、凹部４１内において、第１表面端子４２と第２表面端子４３との間に板ばね４５が挟まれて、板ばね４５が圧縮変形することにより、板ばね４５が第１表面端子４２および第２表面端子４３に確実に当接する。これにより、２個の電極パネル４間で第１表面端子４２と第２表面端子４３とが導通し、電極パネル積層体の各電極パネル４間での導通が確保される。そして、各電極パネル４の非放電部３２は、隙間なく密着し、各電極パネル４の放電部３１間には、放電部３１の一方面３４と非放電部３２の一方面３３との間の段差による間隔が生じる。 In the two electrode panels 4 facing each other of the electrode panel laminated body, the second surface terminal 43 of the electrode panel 4 on one side (upper side) of the stacking direction is a recess of the electrode panel 4 on the other side (lower side) of the stacking direction. Fits in 41. Then, in the recess 41, the leaf spring 45 is sandwiched between the first surface terminal 42 and the second surface terminal 43, and the leaf spring 45 is compressionally deformed, so that the leaf spring 45 becomes the first surface terminal 42 and It surely contacts the second surface terminal 43. As a result, the first surface terminal 42 and the second surface terminal 43 are electrically connected between the two electrode panels 4, and the conduction between each electrode panel 4 of the electrode panel laminate is ensured. Then, the non-discharging portion 32 of each electrode panel 4 is in close contact with each other without a gap, and between the discharging portions 31 of each electrode panel 4, between the one surface 34 of the discharging portion 31 and the one surface 33 of the non-discharging portion 32. There is an interval due to the step.

積層方向の一方側から奇数番目の電極パネル４では、一方の部位の電気導通部４４が内蔵電極２２と導通し、偶数番目の電極パネル４では、他方の部位の電気導通部４４が内蔵電極２２と導通している。一方の部位の第１表面端子４２、第２表面端子４３および電気導通部４４をプラス端子とし、他方の部位の第１表面端子４２、第２表面端子４３および電気導通部４４をマイナス端子として、プラス端子およびマイナス端子には、プラズマリアクタ用電源装置５（図１参照）から出力される高電圧が印加される。高電圧は、直流、交流、パルス波などが挙げられる。これにより、積層方向に互いに隣り合う電極パネル４の内蔵電極２２間に高電圧が印加され、電極パネル４の放電部３１間に誘電体バリア放電が生じ、その誘電体バリア放電によるプラズマが発生する。一方、電極パネル４の放電部３１間には、流入口１１側の端部から排ガスが流入し、その排ガスが流出口１２側の端部に向けて流通する。放電部３１間に発生するプラズマの酸化作用により、放電部３１間を流通する排ガスに含まれるＰＭが酸化（燃焼）されて除去される。 In the electrode panel 4 odd-numbered from one side in the stacking direction, the electrical conduction portion 44 in one portion conducts with the built-in electrode 22, and in the even-numbered electrode panel 4, the electrical conduction portion 44 in the other portion conducts with the built-in electrode 22. Is conducting. The first surface terminal 42, the second surface terminal 43, and the electrical conduction portion 44 of one portion are positive terminals, and the first surface terminal 42, the second surface terminal 43, and the electrical conduction portion 44 of the other portion are negative terminals. A high voltage output from the plasma reactor power supply device 5 (see FIG. 1) is applied to the positive terminal and the negative terminal. Examples of high voltage include direct current, alternating current, and pulse wave. As a result, a high voltage is applied between the built-in electrodes 22 of the electrode panels 4 adjacent to each other in the stacking direction, a dielectric barrier discharge is generated between the discharge portions 31 of the electrode panel 4, and plasma is generated by the dielectric barrier discharge. .. On the other hand, the exhaust gas flows into the discharge portion 31 of the electrode panel 4 from the end portion on the inflow port 11 side, and the exhaust gas circulates toward the end portion on the outflow port 12 side. Due to the oxidizing action of the plasma generated between the discharge units 31, PM contained in the exhaust gas flowing between the discharge units 31 is oxidized (combusted) and removed.

＜作用効果＞
以上のように、複数の電極パネル４が積層方向に積層されている。各電極パネル４は、誘電体平板２１に内蔵電極２２を内蔵した構成を有している。誘電体平板２１は、内蔵電極２２が内蔵される矩形平板状の放電部３１と、放電部３１の両側に放電部３１よりも大きな厚みの非放電部３２とを有している。そのため、複数の電極パネル４の放電部３１間には、放電部３１と非放電部３２との厚さの差による間隔が生じる。互いに対向する内蔵電極２２間に電圧が印加されると、誘電体バリア放電が生じて、放電部３１間にプラズマが発生し、放電部３１間を流れる排ガスに含まれるＰＭがプラズマの酸化作用により除去される。 <Effect>
As described above, the plurality of electrode panels 4 are laminated in the stacking direction. Each electrode panel 4 has a configuration in which a built-in electrode 22 is built in a dielectric flat plate 21. The dielectric flat plate 21 has a rectangular flat plate-shaped discharge portion 31 in which the built-in electrode 22 is built, and a non-discharge portion 32 having a thickness larger than that of the discharge portion 31 on both sides of the discharge portion 31. Therefore, a gap is generated between the discharge portions 31 of the plurality of electrode panels 4 due to the difference in thickness between the discharge portion 31 and the non-discharge portion 32. When a voltage is applied between the built-in electrodes 22 facing each other, a dielectric barrier discharge occurs, plasma is generated between the discharge units 31, and PM contained in the exhaust gas flowing between the discharge units 31 is oxidized by the plasma. Will be removed.

非放電部３２の一方面３３には、凹部４１が形成され、凹部４１の底面には、第１表面端子４２が設けられている。非放電部３２の他方面３５には、その他方面３５に対向する非放電部３２に形成されている凹部４１に嵌まるように第２表面端子４３が設けられている。また、非放電部３２には、第１表面端子４２と第２表面端子４３とを導通させる電気導通部４４が設けられている。そして、凹部４１内には、板ばね４５が設けられ、その板ばね４５が第１表面端子４２と第２表面端子４３との間に挟まれて圧縮変形することにより、上下の電極パネル４間で第１表面端子４２と第２表面端子４３とが導通する。 A recess 41 is formed on one surface 33 of the non-discharging portion 32, and a first surface terminal 42 is provided on the bottom surface of the recess 41. The other surface 35 of the non-discharging portion 32 is provided with a second surface terminal 43 so as to fit into the recess 41 formed in the non-discharging portion 32 facing the other direction 35. Further, the non-discharging portion 32 is provided with an electrically conducting portion 44 that conducts the first surface terminal 42 and the second surface terminal 43. A leaf spring 45 is provided in the recess 41, and the leaf spring 45 is sandwiched between the first surface terminal 42 and the second surface terminal 43 and is compressed and deformed, so that the upper and lower electrode panels 4 are separated from each other. The first surface terminal 42 and the second surface terminal 43 are electrically connected to each other.

上下の電極パネル４において、一方の電極パネル４の第２表面端子４３が他方の電極パネル４の凹部４１に嵌まるので、一方の電極パネル４の非放電部３２の他方面３５と他方の電極パネル４の非放電部３２の一方面３３とを密着させることができる。そのため、上下の電極パネル４の非放電部３２間にＰＭが入ることを抑制できる。 In the upper and lower electrode panels 4, the second surface terminal 43 of one electrode panel 4 fits into the recess 41 of the other electrode panel 4, so that the other surface 35 of the non-discharging portion 32 of one electrode panel 4 and the other electrode One surface 33 of the non-discharged portion 32 of the panel 4 can be brought into close contact with the panel 4. Therefore, it is possible to prevent PM from entering between the non-discharging portions 32 of the upper and lower electrode panels 4.

よって、プラス端子とマイナス端子との間にＰＭによる導電パスが形成されることを抑制でき、プラス端子とマイナス端子との間の絶縁抵抗の低下を抑制できる。その結果、正常な放電を維持でき、端子間ショートによるプラズマリアクタ用電源装置５の故障を防止できる。 Therefore, it is possible to suppress the formation of a conductive path by PM between the positive terminal and the negative terminal, and it is possible to suppress a decrease in the insulation resistance between the positive terminal and the negative terminal. As a result, normal discharge can be maintained, and failure of the plasma reactor power supply device 5 due to a short circuit between terminals can be prevented.

また、非放電部３２間に隙間をなくす構成として、非放電部３２の一方面３３に幅方向の端面で開放される切欠を形成し、切欠の底面にメタライズによる金属膜を形成して、その金属膜にろう付けした端子を引き出す構成が考えられる。しかしながら、かかる構成では、ろう付け部分の劣化や腐食などの問題を生じる可能性があるのに加え、ろう付けや各電極パネル４から引き出した端子間の導通に工数を要し、コストの増大を招くおそれがある。 Further, as a configuration for eliminating a gap between the non-discharging portions 32, a notch opened at the end face in the width direction is formed on one surface 33 of the non-discharging portion 32, and a metallized metal film is formed on the bottom surface of the notch. A configuration is conceivable in which the terminals brazed to the metal film are pulled out. However, in such a configuration, in addition to the possibility of causing problems such as deterioration and corrosion of the brazed portion, man-hours are required for brazing and conduction between the terminals drawn from each electrode panel 4, resulting in an increase in cost. There is a risk of inviting.

＜変形例＞
以上、本発明の一実施形態について説明したが、本発明は、他の形態で実施することもできる。 <Modification example>
Although one embodiment of the present invention has been described above, the present invention can also be implemented in other embodiments.

たとえば、前述の実施形態では、非放電部３２の一方面３２に矩形状の凹部４１が形成されて、凹部４１の底面およびその反対側の他方面３５にそれぞれ第１表面端子４２および第２表面端子４３が設けられ、凹部４１の底面と他方面３５との間を貫通する電気導通部４４により第１表面端子４２と第２表面端子４３とが導通された構成を取り上げた。しかしながら、この構成に限らず、図５および図６に示されるように、凹部４１が幅方向の外側に開放された切欠として形成され、電気導通部４４が非放電部３２の幅方向の端面に設けられて、その端面上の電気導通部４４により第１表面端子４２と第２表面端子４３とが導通されてもよい。 For example, in the above-described embodiment, the rectangular recess 41 is formed on one surface 32 of the non-discharging portion 32, and the first surface terminal 42 and the second surface are formed on the bottom surface of the recess 41 and the other surface 35 on the opposite side, respectively. The configuration in which the terminal 43 is provided and the first surface terminal 42 and the second surface terminal 43 are conducted by an electrically conducting portion 44 penetrating between the bottom surface of the recess 41 and the other surface 35 is taken up. However, the present invention is not limited to this configuration, and as shown in FIGS. 5 and 6, the recess 41 is formed as a notch open to the outside in the width direction, and the electrically conducting portion 44 is formed on the end face of the non-discharging portion 32 in the width direction. The first surface terminal 42 and the second surface terminal 43 may be electrically conducted by the electrically conductive portion 44 on the end surface thereof.

また、前述の実施形態では、各非放電部３２に２個の凹部４１が形成されている構成を取り上げたが、各非放電部３２に形成される凹部４１の個数は、２個に限らず、図５および図６に示されるように、１個であってもよいし、３個以上であってもよい。各非放電部３２に形成される凹部４１の個数が１個である場合、積層方向の一方側から奇数番目の電極パネル４では、一方の非放電部３２の電気導通部４４が内蔵電極２２と導通され、偶数番目の電極パネル４では、他方の非放電部３２の電気導通部４４が内蔵電極２２と導通されて、一方の非放電部３２の第１表面端子４２、第２表面端子４３および電気導通部４４がプラス端子とされ、他方の非放電部３２の第１表面端子４２、第２表面端子４３および電気導通部４４がマイナス端子とされるとよい。 Further, in the above-described embodiment, the configuration in which two recesses 41 are formed in each non-discharged portion 32 is taken up, but the number of recesses 41 formed in each non-discharged portion 32 is not limited to two. , As shown in FIGS. 5 and 6, the number may be one, or three or more. When the number of recesses 41 formed in each non-discharging portion 32 is one, in the electrode panel 4 which is an odd number from one side in the stacking direction, the electrically conducting portion 44 of one non-discharging portion 32 is connected to the built-in electrode 22. In the conductive and even-order electrode panel 4, the electrically conductive portion 44 of the other non-discharging portion 32 is conducted with the built-in electrode 22, and the first surface terminal 42, the second surface terminal 43 and the second surface terminal 43 of the one non-discharging portion 32 are conducted. It is preferable that the electrically conductive portion 44 is a positive terminal, and the first surface terminal 42, the second surface terminal 43, and the electrically conductive portion 44 of the other non-discharging portion 32 are negative terminals.

また、凹部４１内に板ばね４５が設けられているとしたが、板ばね４５に限らず、コイルばね、線ばね、皿ばねなど、導電性を有する材料からなる弾性体が凹部４１内に設けられるとよい。 Further, although it is assumed that the leaf spring 45 is provided in the recess 41, not only the leaf spring 45 but also an elastic body made of a conductive material such as a coil spring, a wire spring, and a disc spring is provided in the recess 41. It would be nice to be done.

その他、前述の構成には、特許請求の範囲に記載された事項の範囲で種々の設計変更を施すことが可能である。 In addition, various design changes can be made to the above-mentioned configuration within the scope of the matters described in the claims.

１：プラズマリアクタ
４：電極パネル
２１：誘電体平板
２２：内蔵電極
３１：放電部
３２：非放電部
３３：一方面
３５：他方面
４１：凹部
４２：第１表面端子
４３：第２表面端子
４４：電気導通部
４５：板ばね（弾性体） 1: Plasma reactor 4: Electrode panel 21: Dielectric flat plate 22: Built-in electrode 31: Discharge part 32: Non-discharge part 33: One side 35: The other side 41: Recessed 42: First surface terminal 43: Second surface terminal 44 : Electric discharge part 45: Leaf spring (elastic body)

Claims

A plasma reactor used to purify the exhaust gas emitted from an engine.
Includes multiple electrode panels stacked in a stacking direction orthogonal to the exhaust gas flow direction,
The electrode panel comprises a dielectric and electrodes.
The dielectric is formed on both sides of a flat plate-shaped discharge portion in which the electrode is built and in a direction orthogonal to both the flow direction and the stacking direction with respect to the discharge portion, and has a thickness larger than that of the discharge portion. Has a non-discharging part of
On one surface of the non-discharging portion in the stacking direction, a recess recessed one step from the one surface is formed.
A first surface terminal is provided on the bottom surface of the recess.
On the other surface of the non-discharging portion in the stacking direction, a second surface terminal that fits into the recess formed in the non-discharging portion facing the other surface is provided.
The non-discharging portion is provided with an electrically conductive portion that electrically connects the first surface terminal and the second surface terminal.
In the recess, a conductive elastic body that is sandwiched between the first surface terminal and the second surface terminal and compresses and deforms is provided in the recess.
The second surface terminal is fitted into the recess, and the elastic body is sandwiched between the first surface terminal and the second surface terminal in the recess and is compressed and deformed, thereby forming the one surface and the one surface. said other surface and are you are in close contact, the plasma reactor of the non-discharge portion.