JP2001252573A - Honeycomb heater - Google Patents
Honeycomb heaterInfo
- Publication number
- JP2001252573A JP2001252573A JP2001077716A JP2001077716A JP2001252573A JP 2001252573 A JP2001252573 A JP 2001252573A JP 2001077716 A JP2001077716 A JP 2001077716A JP 2001077716 A JP2001077716 A JP 2001077716A JP 2001252573 A JP2001252573 A JP 2001252573A
- Authority
- JP
- Japan
- Prior art keywords
- gas
- honeycomb
- honeycomb structure
- locally
- inflow side
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000003054 catalyst Substances 0.000 claims abstract description 69
- 238000005192 partition Methods 0.000 claims abstract description 42
- 238000000034 method Methods 0.000 claims abstract description 38
- 239000004020 conductor Substances 0.000 claims abstract description 14
- 238000010438 heat treatment Methods 0.000 claims description 57
- 230000001747 exhibiting effect Effects 0.000 abstract description 2
- 238000004140 cleaning Methods 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 79
- 229910052751 metal Inorganic materials 0.000 description 17
- 239000002184 metal Substances 0.000 description 17
- 238000000746 purification Methods 0.000 description 17
- 239000000843 powder Substances 0.000 description 16
- 229930195733 hydrocarbon Natural products 0.000 description 12
- 150000002430 hydrocarbons Chemical class 0.000 description 12
- 239000010410 layer Substances 0.000 description 11
- 239000000203 mixture Substances 0.000 description 8
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 6
- 230000001590 oxidative effect Effects 0.000 description 5
- 239000013543 active substance Substances 0.000 description 4
- 239000011230 binding agent Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000001125 extrusion Methods 0.000 description 4
- 239000000446 fuel Substances 0.000 description 4
- 230000020169 heat generation Effects 0.000 description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Substances [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 238000002485 combustion reaction Methods 0.000 description 3
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 3
- 229910052763 palladium Inorganic materials 0.000 description 3
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 3
- 229910052697 platinum Inorganic materials 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 230000008646 thermal stress Effects 0.000 description 3
- 238000011144 upstream manufacturing Methods 0.000 description 3
- WRIDQFICGBMAFQ-UHFFFAOYSA-N (E)-8-Octadecenoic acid Natural products CCCCCCCCCC=CCCCCCCC(O)=O WRIDQFICGBMAFQ-UHFFFAOYSA-N 0.000 description 2
- LQJBNNIYVWPHFW-UHFFFAOYSA-N 20:1omega9c fatty acid Natural products CCCCCCCCCCC=CCCCCCCCC(O)=O LQJBNNIYVWPHFW-UHFFFAOYSA-N 0.000 description 2
- QSBYPNXLFMSGKH-UHFFFAOYSA-N 9-Heptadecensaeure Natural products CCCCCCCC=CCCCCCCCC(O)=O QSBYPNXLFMSGKH-UHFFFAOYSA-N 0.000 description 2
- ZQPPMHVWECSIRJ-UHFFFAOYSA-N Oleic acid Natural products CCCCCCCCC=CCCCCCCCC(O)=O ZQPPMHVWECSIRJ-UHFFFAOYSA-N 0.000 description 2
- 239000005642 Oleic acid Substances 0.000 description 2
- 239000003963 antioxidant agent Substances 0.000 description 2
- 230000003078 antioxidant effect Effects 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 239000011888 foil Substances 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000011810 insulating material Substances 0.000 description 2
- QXJSBBXBKPUZAA-UHFFFAOYSA-N isooleic acid Natural products CCCCCCCC=CCCCCCCCCC(O)=O QXJSBBXBKPUZAA-UHFFFAOYSA-N 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- 150000004706 metal oxides Chemical class 0.000 description 2
- 229920000609 methyl cellulose Polymers 0.000 description 2
- 239000001923 methylcellulose Substances 0.000 description 2
- 235000010981 methylcellulose Nutrition 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 229910000510 noble metal Inorganic materials 0.000 description 2
- ZQPPMHVWECSIRJ-KTKRTIGZSA-N oleic acid Chemical compound CCCCCCCC\C=C/CCCCCCCC(O)=O ZQPPMHVWECSIRJ-KTKRTIGZSA-N 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 238000007747 plating Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 229910052703 rhodium Inorganic materials 0.000 description 2
- 239000010948 rhodium Substances 0.000 description 2
- 230000035939 shock Effects 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- OENIXTHWZWFYIV-UHFFFAOYSA-N 2-[4-[2-[5-(cyclopentylmethyl)-1h-imidazol-2-yl]ethyl]phenyl]benzoic acid Chemical compound OC(=O)C1=CC=CC=C1C(C=C1)=CC=C1CCC(N1)=NC=C1CC1CCCC1 OENIXTHWZWFYIV-UHFFFAOYSA-N 0.000 description 1
- 208000019901 Anxiety disease Diseases 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 229910002060 Fe-Cr-Al alloy Inorganic materials 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 102100027340 Slit homolog 2 protein Human genes 0.000 description 1
- 101710133576 Slit homolog 2 protein Proteins 0.000 description 1
- 229910010413 TiO 2 Inorganic materials 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 230000036506 anxiety Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 229910000963 austenitic stainless steel Inorganic materials 0.000 description 1
- 239000010953 base metal Substances 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 239000011195 cermet Substances 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 229910052878 cordierite Inorganic materials 0.000 description 1
- JSKIRARMQDRGJZ-UHFFFAOYSA-N dimagnesium dioxido-bis[(1-oxido-3-oxo-2,4,6,8,9-pentaoxa-1,3-disila-5,7-dialuminabicyclo[3.3.1]nonan-7-yl)oxy]silane Chemical compound [Mg++].[Mg++].[O-][Si]([O-])(O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2)O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2 JSKIRARMQDRGJZ-UHFFFAOYSA-N 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- GPNDARIEYHPYAY-UHFFFAOYSA-N palladium(ii) nitrate Chemical compound [Pd+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O GPNDARIEYHPYAY-UHFFFAOYSA-N 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- -1 perovskite Inorganic materials 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 239000011241 protective layer Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- VXNYVYJABGOSBX-UHFFFAOYSA-N rhodium(3+);trinitrate Chemical compound [Rh+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VXNYVYJABGOSBX-UHFFFAOYSA-N 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Catalysts (AREA)
- Exhaust Gas After Treatment (AREA)
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】 本発明は、内燃機関から排
出される排ガス中の炭化水素（ＨＣ）、一酸化炭素（Ｃ
Ｏ）、窒素酸化物（ＮＯx）等の有害成分、特にエンジ
ン始動時（コールドスタート時）に多量発生するＨＣを
効果的に浄化するための排ガス浄化システムにおいて好
適に使用できる通電発熱型のハニカムヒーター及びその
運転方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to hydrocarbons (HC) and carbon monoxide (C) in exhaust gas discharged from an internal combustion engine.
O), nitrogen oxides (NO x ), and other harmful components, in particular, a heat generation type honeycomb that can be suitably used in an exhaust gas purification system for effectively purifying HC generated in large quantities at the time of engine start (cold start). The present invention relates to a heater and an operation method thereof.
【０００２】[0002]
【従来の技術】 従来、自動車の排ガス中のＨＣ、Ｃ
Ｏ、ＮＯx等の有害成分を浄化するための自動車排ガス
浄化システムの研究開発が活発に行われているが、特に
近年においては、排ガス規制の強化とともに、コールド
スタート時におけるこれら有害物質の浄化が重要な技術
課題となっている。すなわち、エンジン始動直後のよう
に排ガスの温度が低いときは、触媒がその作用温度に到
達していないので浄化能が低く、その上、この時期は、
定常走行時に比して多量のＨＣが排出される。2. Description of the Related Art Conventionally, HC and C in exhaust gas of automobiles have been used.
O, research and development of an automobile exhaust gas purification system for purifying harmful components such as NO x have been actively, especially in recent years, along with reinforcement of exhaust gas regulations, the purification of these harmful substances at a cold start It is an important technical issue. That is, when the temperature of the exhaust gas is low, such as immediately after the start of the engine, since the catalyst has not reached its operating temperature, the purification ability is low.
A larger amount of HC is discharged than during steady running.
【０００３】 このような技術課題を解決するための手
段の１つとして、通電発熱型ヒーターをエンジン始動前
あるいはエンジン始動と同時に通電し、ヒーター上に担
持させた触媒や、ヒーターの後方に近接させて配置した
いわゆるライトオフ触媒、メイン触媒等を触媒の作用温
度まで速やかに昇温する技術が注目されている。As one of means for solving such a technical problem, an energizing and heating type heater is energized before the engine is started or simultaneously with the start of the engine so that a catalyst carried on the heater or a heater provided near the heater is provided. Attention has been focused on a technique for quickly raising the temperature of a so-called light-off catalyst, main catalyst, or the like, which is arranged at a predetermined temperature, to the operating temperature of the catalyst.
【０００４】 例えば、本願出願人が先に出願した特開
平３−２９５１８４号公報には、多数の貫通孔を有する
ハニカム構造体に、通電のための少なくとも２つの電極
を設けるとともに、該電極間にスリット等の抵抗調節機
構を設けた抵抗調節型ヒーターが開示されている。For example, Japanese Patent Application Laid-Open No. 3-295184 filed earlier by the applicant of the present application discloses that a honeycomb structure having a large number of through holes is provided with at least two electrodes for energization and between the electrodes. A resistance-adjustment type heater provided with a resistance adjustment mechanism such as a slit is disclosed.
【０００５】 また、特開平５−１３８０４２号公報に
は、消費電力の少ない発熱式メタル担体触媒を目的に、
排ガスの流入側にメタル担体の通電経路の抵抗が局所的
に大きくなる部分を有した局所発熱型のヒーターの記載
があり、局所加熱部の抵抗調節方法としては、孔部又は
スリット部をヒーターに配設すること、また、メタル担
体を構成する金属箔の肉厚を変えることが開示されてい
る。[0005] Also, Japanese Patent Application Laid-Open No. 5-138042 discloses an exothermic metal carrier catalyst with low power consumption.
On the inflow side of the exhaust gas, there is a description of a local heating type heater having a portion where the resistance of the current path of the metal carrier locally increases, and as a method of adjusting the resistance of the local heating unit, a hole or a slit is provided to the heater. It is disclosed to dispose and to change the thickness of a metal foil constituting a metal carrier.
【０００６】 更に、特開平５−１６８９４６号公報に
は、表面に絶縁被膜が形成された金属製の薄板を積層し
てなる金属製触媒担体の一定の領域にのみ通電加熱する
ヒーターの記載があり、具体的には部分的に薄板をロウ
付け、放電溶接、レーザー溶接等によって通電可能に接
合し抵抗を減じることによって、薄板の非接合領域にの
み優先的に加熱する触媒装置が開示されている。Further, Japanese Patent Application Laid-Open No. 5-168946 describes a heater for energizing and heating only a certain area of a metal catalyst carrier formed by laminating metal thin plates having an insulating film formed on the surface. Specifically, a catalyst device is disclosed in which a thin plate is partially brazed, and is electrically connected by discharge welding, laser welding, or the like so as to reduce resistance and thereby preferentially heat only a non-joined region of the thin plate. .
【０００７】[0007]
【発明が解決しようとする課題】 しかしながら、上記
特開平３−２９５１８４号公報記載の抵抗調節型ヒータ
ーにおいては、ヒーター全体を加熱する場合、少量の投
入電力では昇温速度が遅いためにヒーター上に担持した
触媒を短時間で着火温度に到達させることができず、結
果的にコールドスタート時に多量発生するＨＣの大部分
が未浄化のまま吹き抜けてしまうことになる。一方、大
きな電力を投入してヒーターを急峻に加熱するには、大
容量のバッテリーや重装備のケーブル、制御装置が必要
となる。However, in the resistance-adjustment type heater described in Japanese Patent Application Laid-Open No. 3-295184, when heating the entire heater, the heating rate is slow with a small amount of input power. The supported catalyst cannot reach the ignition temperature in a short time, and as a result, most of the HC generated in a large amount at the time of cold start blows through without being purified. On the other hand, a steep heating of the heater by applying a large amount of power requires a large-capacity battery, heavy equipment cables, and a control device.
【０００８】 また、特開平５−１３８０４２号公報や
特開平５−１６８９４６号公報に記載されているような
局所発熱型のものを用いれば、発熱部の熱容量を小さく
できるので少量の投入電力で発熱部を短時間に発熱させ
られるが、発熱部以外の温度の低い箇所も存在するの
で、コールドスタート時にここを通過するＨＣの大部分
は未浄化のまま吹き抜けてしまうことになる。そして、
ガス通過部全体に対する発熱部の割合や運転方法につい
て特に規定されていないため、十分な浄化性能を得るの
が困難であった。Further, if a local heat generation type described in Japanese Patent Application Laid-Open Nos. 5-138042 and 5-168946 is used, the heat capacity of the heat generating portion can be reduced, so that heat is generated with a small input power. The portion can be heated in a short time, but since there are low-temperature portions other than the heat-generating portion, most of the HC passing therethrough at the cold start blows through without being purified. And
It is difficult to obtain sufficient purification performance because the ratio of the heat generating portion to the entire gas passage portion and the operation method are not particularly specified.
【０００９】 本発明は、上記のような従来の事情を考
慮してなされたものであり、少ない電力で好適な浄化性
能を発揮し得るハニカムヒーターとその運転方法を提供
することを目的とする。The present invention has been made in consideration of the above-described conventional circumstances, and an object of the present invention is to provide a honeycomb heater capable of exhibiting a suitable purification performance with a small amount of electric power, and an operation method thereof.
【００１０】[0010]
【課題を解決するための手段】 上記目的を達成するた
め、本発明によれば、導電性材料からなる隔壁に仕切ら
れたガス流れ方向に実質的に平行な多数の貫通孔を有
し、ガス流入側及びガス流出側の両端面を有するハニカ
ム構造体と、該ハニカム構造体に設けられた通電のため
の少なくとも２つの電極とを含むハニカムヒーターであ
って、前記隔壁上には触媒層が被覆担持され、通電時に
少なくともガス流入側端面近傍を含む特定の領域が、他
の領域に比して局所的に急速加熱できるよう抵抗が調節
され、かつ前記局所的に急速加熱される特定の領域の面
積がガス通過断面積の５〜５０％の範囲にあることを特
徴とするハニカムヒーター、が提供される。Means for Solving the Problems To achieve the above object, according to the present invention, a partition made of a conductive material has a large number of through holes substantially parallel to the gas flow direction, A honeycomb heater including a honeycomb structure having both end faces on an inflow side and a gas outflow side, and at least two electrodes for energization provided in the honeycomb structure, wherein a catalyst layer is coated on the partition walls. The specific region that is carried and includes at least the vicinity of the gas inflow side end surface at the time of energization is adjusted in resistance so that the specific region can be rapidly heated as compared with other regions, and the specific region that is locally heated rapidly. A honeycomb heater is provided, wherein an area is in a range of 5 to 50% of a gas passage sectional area.
【００１１】 更に、本発明によれば、導電性材料から
なる隔壁に仕切られたガス流れ方向に実質的に平行な多
数の貫通孔を有し、ガス流入側及びガス流出側の両端面
を有するハニカム構造体と、該ハニカム構造体に設けら
れた通電のための少なくとも２つの電極とを含むハニカ
ムヒーターであって、前記隔壁上には触媒層が被覆担持
され、前記ハニカム構造体には、ガス通過断面の大部分
又は特定の部分を発熱するように、複数かつ平行にスリ
ットが配設され、更に少なくともガス流入側端面近傍を
含む特定の領域が他の領域に比して局所的に急速加熱で
きるように、ガス流出側端面より少なくとも１つの孔が
ガス流入側端面まで到達しないよう配設されるか、前記
貫通孔の孔相当直径、セル密度若しくは前記隔壁の厚さ
を部分的に変化させるか、又は前記ハニカム構造体の隔
壁に部分的にスリットが設けられており、かつ前記局所
的に急速加熱される特定の領域の面積がガス通過断面積
の５〜５０％の範囲にあることを特徴とするハニカムヒ
ーター、が提供される。Further, according to the present invention, there are provided a large number of through-holes substantially parallel to a gas flow direction, which are partitioned by partition walls made of a conductive material, and have both end faces on a gas inflow side and a gas outflow side. A honeycomb heater including a honeycomb structure, and at least two electrodes for energization provided in the honeycomb structure, wherein a catalyst layer is coated and supported on the partition walls, and the honeycomb structure includes a gas. A plurality of slits are arranged in parallel so as to generate heat in most or a specific part of the passage section, and a specific area including at least the vicinity of the gas inflow side end face is locally heated more rapidly than other areas. At least one hole from the gas outflow end face is disposed so as not to reach the gas inflow side end face, or the hole equivalent diameter of the through hole, the cell density, or the thickness of the partition wall is partially changed. Or a slit is partially provided in a partition wall of the honeycomb structure, and an area of the specific region which is locally rapidly heated is in a range of 5 to 50% of a gas passage sectional area. The present invention provides a honeycomb heater, characterized in that:
【００１２】 更にまた、本発明によれば、導電性材料
からなる隔壁に仕切られたガス流れ方向に実質的に平行
な多数の貫通孔を有し、ガス流入側及びガス流出側の両
端面を有するハニカム構造体と、該ハニカム構造体に設
けられた通電のための少なくとも２つの電極とを含むハ
ニカムヒーターであって、前記隔壁上には触媒層が被覆
担持され、通電時に少なくともガス流入側端面近傍を含
む特定の領域が、他の領域に比して局所的に急速加熱で
きるよう抵抗が調節され、かつ前記局所的に急速加熱さ
れる特定の領域の面積がガス通過断面積の５〜５０％の
範囲にあるハニカムヒーターを用いて、コールドスター
ト時から２０秒以内に前記局所的に急速加熱される特定
の領域が触媒着火温度に到達するように通電することを
特徴とするハニカムヒーターの運転方法、が提供され
る。Further, according to the present invention, a partition wall made of a conductive material has a large number of through holes substantially parallel to a gas flow direction, and both end faces on a gas inflow side and a gas outflow side are provided. A honeycomb heater comprising: a honeycomb structure having a honeycomb structure; and at least two electrodes for energization provided on the honeycomb structure, wherein a catalyst layer is coated and supported on the partition walls, and at least a gas inflow side end surface when energized. The resistance is adjusted so that a specific region including the vicinity can be rapidly heated locally compared to other regions, and the area of the locally rapidly heated specific region is 5 to 50 times the gas passage cross-sectional area. % By using a honeycomb heater in the range of 20% from the time of cold start so that the specific region to be rapidly heated locally reaches the catalyst ignition temperature within 20 seconds. A method of operating a heater is provided.
【００１３】[0013]
【発明の実施の形態】 上記のように、本発明のハニカ
ムヒーターは、通電時に少なくともガス流入側端面近傍
を含む特定の領域が、他の領域に比して局所的に急速加
熱できるよう抵抗が調節された部分発熱型（局所発熱
型）のヒーターであり、上記局所的に急速加熱される特
定の領域（以下、この領域を「急速加熱部」といい、他
の領域を「低速加熱部」という）の面積をガス通過断面
積の５〜５０％の範囲に限定したことを主要な特徴とす
る。急速加熱部の面積をかかる範囲に限定したことによ
り、比較的小さな投入電力で良好な排ガス浄化能が得ら
れ、特にコールドスタート時に多量発生するＨＣを効率
よく浄化できる。DETAILED DESCRIPTION OF THE INVENTION As described above, the honeycomb heater of the present invention has a resistance so that a specific area including at least the vicinity of the gas inflow side end face can be locally heated more rapidly than other areas when energized. This is a regulated partial heating type (local heating type) heater, and the above-described specific area which is rapidly heated locally (hereinafter, this area is referred to as “rapid heating section”, and the other areas are referred to as “slow heating section”). ) Is limited to a range of 5 to 50% of the gas passage cross-sectional area. By limiting the area of the rapid heating section to such a range, good exhaust gas purification performance can be obtained with relatively small input power, and particularly, HC generated in large quantities at the time of cold start can be efficiently purified.
【００１４】 急速加熱部の面積がガス通過断面積の５
％未満では、低速加熱部でのガスの吹き抜けが大きくな
ると同時に、急速加熱部の触媒による反応熱があまり期
待できず浄化効率が低下する。一方、５０％を超える
と、急速加熱部の質量も大きくなるので、投入電力を大
きくする必要が発生し、電力の削減効果が小さくなる。
なお、ガス通過断面積に対する急速加熱部の面積の割合
の好ましい範囲としては１０〜４０％であり、これによ
り、ガス通過断面のほとんど全部が均等に発熱する全体
発熱型のヒーターを加熱するのに要する投入電力に対し
３０％以上の電力が削減でき、同程度の浄化効率を示
す。The area of the rapid heating section is 5 times the cross-sectional area of the gas passage.
%, The gas blow-through in the low-speed heating section becomes large, and at the same time, the reaction heat by the catalyst in the rapid heating section cannot be expected so much, and the purification efficiency decreases. On the other hand, if it exceeds 50%, the mass of the rapid heating unit also increases, so that it becomes necessary to increase the input power, and the power reduction effect decreases.
The preferred range of the ratio of the area of the rapid heating section to the cross-sectional area of the gas passage is 10 to 40%. 30% or more of the required input power can be reduced, and the same purification efficiency is exhibited.
【００１５】 以下、本発明を詳細に説明する。本発明
において、ハニカム構造体を構成する導電性材料として
は、フェライト系ステンレス、オーステナイト系ステン
レス等の金属質、ペロブスカイト系、ＳｉＣ等のセラミ
ック質等のいかなる材料も用いることができるが、耐熱
性、耐熱衝撃性の点でＦｅ−Ｃｒ−Ａｌからなるフェラ
イト系ステンレスが最も好ましい。また、隔壁自体が導
電性材質ではなく、例えばコーディエライトのような絶
縁材料にＰｔやサーメットからなる導電性物質を、メッ
キやスパッタリング等の手法を用いてコートし、コート
した導電生物質が通電により発熱するようにしてもよ
い。Hereinafter, the present invention will be described in detail. In the present invention, as the conductive material constituting the honeycomb structure, any material such as ferritic stainless steel, austenitic stainless steel or any other metal, perovskite, or SiC or any other ceramic material can be used. A ferritic stainless steel made of Fe-Cr-Al is most preferable in terms of thermal shock resistance. In addition, the partition walls themselves are not conductive materials, and for example, an insulating material such as cordierite is coated with a conductive material made of Pt or cermet using a method such as plating or sputtering. Heat may be generated.
【００１６】 ハニカム構造体は、金属箔を巻き取って
作製されたものでも、また、粉末冶金法による押し出し
法によって作製されたものでもよいが、構造耐久性の
点、特に過酷な条件下でのテレスコープ現象を避けるた
めに押し出し法によって調製されたものが好ましい。貫
通孔の断面形状（セル形状）は、特に限定されるもので
はなく四角形、六角形等の多角形、円形、コルゲート形
等の各種の任意の形状を用いることができるが、耐熱衝
撃性の点から熱応力を緩和するフレキシブルなセル形
状、例えば六角形が好ましい。The honeycomb structure may be manufactured by winding a metal foil, or may be manufactured by an extrusion method based on a powder metallurgy method. However, the honeycomb structure may have a structural durability, particularly under severe conditions. Those prepared by the extrusion method are preferred to avoid telescoping. The cross-sectional shape (cell shape) of the through hole is not particularly limited, and various arbitrary shapes such as a polygon such as a square and a hexagon, a circle, a corrugated shape, etc. can be used. For example, a flexible cell shape that alleviates thermal stress, such as a hexagon, is preferable.
【００１７】 次に、本発明で用いるハニカム構造体の
うち、金属質ハニカム構造体の製造方法の例を説明す
る。まず、所望の組成となるように、例えばＦｅ粉末、
Ａｌ粉末、Ｃｒ粉末、又はこれらの合金粉末などにより
金属粉末原料を調製する。次いで、このように調製され
た金属粉末原料と、メチルセルロース、ポリビニルアル
コール等の有機バインダー、水を混合した後、この混合
物を所望のハニカム形状に押出成形する。なお、金属粉
末原料と有機バインダー、水の混合に際し、水を添加す
る前に金属粉末にオレイン酸等の酸化防止剤を混合する
か、あるいは予め酸化されない処理を施した金属粉末を
使用することが好ましい。Next, among the honeycomb structures used in the present invention, an example of a method for manufacturing a metallic honeycomb structure will be described. First, for example, Fe powder so as to have a desired composition,
A metal powder raw material is prepared from an Al powder, a Cr powder, or an alloy powder thereof. Next, after mixing the thus prepared metal powder raw material, an organic binder such as methyl cellulose and polyvinyl alcohol, and water, the mixture is extruded into a desired honeycomb shape. In addition, when mixing the metal powder raw material with the organic binder and water, it is possible to mix an antioxidant such as oleic acid into the metal powder before adding water, or to use a metal powder that has been subjected to a treatment that is not oxidized in advance. preferable.
【００１８】 次に、押出成形されたハニカム成形体
を、非酸化雰囲気下１０００〜１４００℃で焼成する。
ここで、水素を含む非酸化雰囲気下において焼成を行う
と、有機バインダーがＦｅ等を触媒にして分解除去され
るので、良好な焼結体を得ることができ、好ましい。焼
成温度が１０００℃未満の場合、成形体が焼結せず、焼
成温度が１４００℃を超えると得られる焼結体が変形す
るため、好ましくない。Next, the extruded honeycomb formed body is fired at 1000 to 1400 ° C. in a non-oxidizing atmosphere.
Here, when calcination is performed in a non-oxidizing atmosphere containing hydrogen, the organic binder is decomposed and removed using Fe or the like as a catalyst, so that a favorable sintered body can be obtained, which is preferable. If the firing temperature is lower than 1000 ° C., the compact is not sintered, and if the firing temperature is higher than 1400 ° C., the obtained sintered body is undesirably deformed.
【００１９】 なお、望ましくは、次いで、得られた焼
結体の隔壁及び気孔の表面を耐熱性金属酸化物で被覆す
る。この耐熱性金属酸化物による被覆方法としては、下
記の方法が好ましいものとして挙げられる。 金属ハニカム構造体を酸化雰囲気中７００〜１１００
℃で熱処理する。 Ａｌ等を焼結体の隔壁及び気孔の表面にメッキ（例え
ば気相メッキ）し、酸化雰囲気中７００〜１１００℃で
熱処理する。 Ａｌ等の金属溶湯中に浸漬し、酸化雰囲気中７００〜
１１００℃で熱処理する。 アルミナゾル等を用い焼結体の隔壁及び気孔の表面に
被覆し、酸化雰囲気中７００〜１１００℃で熱処理す
る。なお、熱処理温度は、耐熱性、耐酸化性の点で、９
００〜１１００℃とすることが好ましい。Preferably, the surfaces of the partition walls and pores of the obtained sintered body are coated with a heat-resistant metal oxide. As a method of coating with the heat-resistant metal oxide, the following method is preferred. 700-1100 metal oxidation honeycomb structure in oxidizing atmosphere
Heat treatment at ℃. Al and the like are plated (for example, vapor phase plating) on the surfaces of the partition walls and pores of the sintered body, and heat-treated at 700 to 1100 ° C. in an oxidizing atmosphere. Dipped in a molten metal such as Al
Heat treatment at 1100 ° C. The surface of the partition walls and pores of the sintered body is coated with alumina sol or the like, and heat-treated at 700 to 1100 ° C. in an oxidizing atmosphere. The heat treatment temperature is 9 in terms of heat resistance and oxidation resistance.
The temperature is preferably set to 00 to 1100 ° C.
【００２０】 上記ハニカム構造体には、通電のための
少なくとも２つの電極が取り付けられる。なお、ここで
いう電極とはアース側の電極をも含む。電極は一般には
バッテリー、キャパシター等の電源にスイッチ、制御装
置を介して接続され、通電することができる。電極の取
り付け位置は、ハニカム構造体の外周部、内部のいずれ
の位置も可能である。[0020] At least two electrodes for energization are attached to the honeycomb structure. Here, the electrodes include the electrodes on the ground side. The electrodes are generally connected to a power source such as a battery or a capacitor via a switch or a control device, and can be energized. The electrode can be attached at any position on the outer peripheral portion or inside the honeycomb structure.
【００２１】 ハニカム構造体の隔壁上には、触媒活性
物質を含む触媒層が被覆担持されていることが必須であ
る。すなわち、この隔壁上の触媒層が通電によりまず着
火して、そこから生み出される反応熱がハニカムヒータ
ー上の触媒の加熱、又は通常このヒーターの後流側に配
置されるライトオフ触媒やメイン触媒の加熱を加速し、
小さな投入電力で好適な浄化性能を示す。It is essential that a catalyst layer containing a catalytically active substance is coated and supported on the partition walls of the honeycomb structure. That is, the catalyst layer on the partition walls is first ignited by energization, and the reaction heat generated therefrom heats the catalyst on the honeycomb heater, or the light-off catalyst or main catalyst which is usually disposed downstream of the heater. Accelerate heating,
It shows suitable purification performance with small input power.
【００２２】 ハニカム構造体の隔壁上に担持する触媒
層は、大きな表面積を有する担体に触媒活性物質を担持
させたものからなる。ここで、大きな表面積を有する担
体としては、例えばγ−Ａｌ2Ｏ3系、ＴｉＯ2系、Ｓｉ
Ｏ2−Ａｌ2Ｏ3系などやペロブスカイト系のものが代表
的なものとして挙げられる。触媒活性物質としては、例
えばＰｔ、Ｐｄ、Ｒｈ等の貴金属、Ｃｕ、Ｎｉ、Ｃｒ、
Ｃｏ等の卑金属などを挙げることができる、上記のう
ち、γ−Ａｌ2Ｏ3系にＰｔ、Ｐｄ、Ｐｈ等の貴金属のい
ずれか、又はこれらの任意の組み合わせを担持したもの
が好ましい。The catalyst layer carried on the partition walls of the honeycomb structure is formed by carrying a catalytically active substance on a carrier having a large surface area. Here, as the carrier having a large surface area, for example, γ-Al 2 O 3 system, TiO 2 system, Si
Typical examples include O 2 —Al 2 O 3 and perovskite. Examples of the catalytically active substance include noble metals such as Pt, Pd, and Rh, Cu, Ni, Cr,
Base metals such as Co can be mentioned. Of the above, preferred are those in which any of noble metals such as Pt, Pd, and Ph, or any combination thereof is supported on a γ-Al 2 O 3 system.
【００２３】 このようにして、構成される本発明のハ
ニカムヒーターは、ガス流入側とガス流出側の端面を有
し、排ガスはガス流入側端面から、貫通孔を経由してガ
ス流出側端面に至る。ハニカムヒーターは、通常金属質
の缶体の中に、好ましくは絶縁された状態で保持され、
排ガスが缶体内のハニカムヒーターのガス流入側端面へ
導かれるように配管される。The honeycomb heater of the present invention configured as described above has end faces on the gas inflow side and the gas outflow side, and the exhaust gas flows from the gas inflow side end face to the gas outflow side end face via the through hole. Reach. The honeycomb heater is usually held in a metallic can body, preferably in an insulated state,
The pipe is arranged such that the exhaust gas is guided to the end face on the gas inflow side of the honeycomb heater in the can body.
【００２４】 ハニカムヒーターは通電により加熱され
るが、少なくともガス流入側端面近傍を含むある特定の
領域が、ヒーターの他の領域に比して、局所的に急速加
熱するよう抵抗調節されていることが必要である。少な
くともガス流入側端面近傍を含むように急速加熱部を配
設する理由は、前述のとおりハニカムヒーター上流部を
局所的に急速加熱することにより、ハニカムヒーターの
上流部の触媒層が着火して得られた反応熱を下流部へ伝
藩し、ハニカムヒーターの下流側の触媒層あるいはハニ
カムヒーター下流部に配設するライトオフ触媒等を加熱
することができるからである。逆にガス流出側端面近傍
だけを通電加熱する場合は、ガス流入側端面近傍が加熱
されないため、ヒートシンクとして作用し、投入電力及
び浄化効率の点で劣る。[0024] The honeycomb heater is heated by energization, and the resistance of a specific area including at least the vicinity of the gas inflow side end face is adjusted so that local rapid heating is performed as compared with other areas of the heater. is necessary. The reason for arranging the rapid heating section so as to include at least the vicinity of the end face on the gas inflow side is that the catalyst layer in the upstream section of the honeycomb heater is ignited by locally rapidly heating the upstream section of the honeycomb heater as described above. This is because the reaction heat obtained can be transferred to the downstream portion, and the catalyst layer on the downstream side of the honeycomb heater or the light-off catalyst disposed on the downstream portion of the honeycomb heater can be heated. On the other hand, when only the vicinity of the gas outflow side end face is energized and heated, the vicinity of the gas inflow side end face is not heated, so that it acts as a heat sink and is inferior in input power and purification efficiency.
【００２５】 ガス流入側端面からガス排出側端面へガ
ス流れ方向に従って均一に（ガス通過断面に対しては局
所的に）急速加熱させるのも好適な態様の１つである。
この場合ヒーター上の触媒で発生した多量の反応熱が、
通常ヒーターの直後に配設されるライトオフ触媒又はメ
イン触媒を早期活性化するのに役立つ。ガス流入側端面
からガス流出側端面へガス流れ方向に不均一に急速加熱
する場合でも、少なくともガス流入側端面近傍が局所的
に急速加熱されることが肝要である。It is also a preferable embodiment to perform rapid heating uniformly (locally with respect to a gas passage section) from the gas inlet side end face to the gas discharge side end face in the gas flow direction.
In this case, a large amount of reaction heat generated by the catalyst on the heater is
It is useful for early activation of the light-off catalyst or the main catalyst which is usually disposed immediately after the heater. Even in the case of non-uniform rapid heating in the gas flow direction from the gas inflow side end face to the gas outflow side end face, it is important that at least the vicinity of the gas inflow side end face be rapidly heated locally.
【００２６】 なお、本発明において、「局所的に急速
加熱される」とは、急速加熱部と低速加熱部（非発熱部
を含む）が、ヒーター内部にそれぞれ１箇所又は複数箇
所存在し、急速加熱部が触媒着火温度に到達した時、低
速加熱部が触媒着火温度より５０℃以上、好ましくは１
００℃以上低い温度を示すように加熱されることをい
う。５０℃未満の温度差では、ヒーターが全体発熱に近
づくために、目的とする投入電力の低減に対する効果は
小さい。１００℃以上の温度差がある場合は、比較的小
さな投入電力で好適な浄化能を示す。In the present invention, “locally rapidly heated” means that a rapid heating section and a low-speed heating section (including a non-heating section) are present at one or more locations inside the heater, respectively, When the heating section reaches the catalyst ignition temperature, the low-speed heating section raises the catalyst ignition temperature by 50 ° C. or more, preferably 1 ° C or more.
It means that it is heated to show a temperature lower than 00 ° C. At a temperature difference of less than 50 ° C., the heater approaches the entire heat generation, so that the effect on the intended reduction of the input power is small. When there is a temperature difference of 100 ° C. or more, a suitable purification ability is exhibited with relatively small input power.
【００２７】 更に「触媒着火温度」とは、触媒が吹き
消えずに継続的に反応が起こるときの温度をいい、３５
０℃以上の温度が一つの目安となる。触媒は長時間の耐
久によって劣化し、さらには局所発熱型ヒーターの場
合、低速加熱部の熱引きの問題もあるので、５００℃以
上の温度であれば確実に触媒着火温度に到達したと考え
てよい。Further, the “catalyst light-off temperature” refers to a temperature at which a reaction continuously occurs without blowing out a catalyst, and 35
A temperature of 0 ° C. or higher is one measure. The catalyst deteriorates due to long-term durability, and furthermore, in the case of a local heating type heater, there is also a problem of heat removal in a low-speed heating section. Good.
【００２８】 急速加熱部が、低速加熱部に比して局所
的に急速加熱できるようにするための抵抗調節の手段と
しては次のような手法を用いることができる。まず、第
１の手法としては、図１に示すように電極５を設けたハ
ニカム構造体１にスリット２を配設する手法が挙げられ
る。図１の例では、スリット２間に挟まれた斜線領域の
抵抗が大きいため、この斜線領域が優先的に発熱し急速
加熱部となる。この場合、図１(ａ)の平面図に示すよう
にガス通過断面に対しては、中心部分が局所発熱する
が、図１(ｂ)の正面図に示すように、ガス流れ方向に対
しては、均一に発熱する。The following method can be used as a means for adjusting the resistance so that the rapid heating unit can perform local rapid heating as compared with the low-speed heating unit. First, as a first technique, there is a technique of arranging a slit 2 in a honeycomb structure 1 provided with an electrode 5 as shown in FIG. In the example of FIG. 1, since the resistance of the hatched area sandwiched between the slits 2 is large, the hatched area generates heat preferentially and serves as a rapid heating unit. In this case, as shown in the plan view of FIG. 1 (a), the central portion locally generates heat with respect to the gas passage cross section, but as shown in the front view of FIG. Generates heat uniformly.
【００２９】 このように、少なくともガス流入側端面
近傍を含む特定の領域を、他のヒーター部分に比し局所
的に急速加熱できるようにスリットを設けることが必要
である。ハニカム構造体の斜線以外の部分、すなわち低
速加熱部は、スリットの入れ方にも依存するが、発熱す
る場合も、ほとんど発熱しない場合もある。ガス通過断
面積は、ハニカムヒーターを缶体に保持して用いる場合
は、その保持の方法によって変化するため、必ずしもハ
ニカム構造体の断面積とは一致しない。なお、ハニカム
構造体に設けるスリットの本数には特に制限はない。As described above, it is necessary to provide a slit so that a specific area including at least the vicinity of the gas inflow side end face can be locally heated more rapidly than other heater parts. The portion other than the diagonal lines of the honeycomb structure, that is, the low-speed heating portion, generates heat or hardly generates heat depending on the slitting method. When the honeycomb heater is used while being held by the can body, the gas passage cross-sectional area does not always match the cross-sectional area of the honeycomb structure because it varies depending on the holding method. The number of slits provided in the honeycomb structure is not particularly limited.
【００３０】 上記第１の手法の応用として、スリット
の代わりにガス流れ方向に垂直に伸びた孔を設けてもよ
い。また、貫通孔の孔相当直径、セル密度あるいは隔壁
の厚さを部分的に変化させたり、ハニカム構造体の隔壁
（リブ部）に部分的にスリット（途切れ）を設けること
により抵抗を調節し、急速加熱部が形成されるようにし
てもよい。As an application of the first method, a hole extending perpendicular to the gas flow direction may be provided instead of the slit. In addition, the resistance is adjusted by partially changing the hole equivalent diameter of the through hole, the cell density or the thickness of the partition wall, or providing a slit (interruption) partially in the partition wall (rib portion) of the honeycomb structure, A rapid heating section may be formed.
【００３１】 第２の手法としては、図２に示すように
スリット２をガス通過断面の大部分又は特定の部分を発
熱するよう複数かつ平行に配し、更にガス流出側端面７
よりガス流入端面６まで到達しないように孔８を穿つ方
法がある。図２(ａ)の平面図及び図２(ｂ)の正面図に斜
線で示すように、これらスリット２及び孔８によって、
ガス流入側端面６近傍の孔８上に急速加熱部が形成され
る。As a second method, as shown in FIG. 2, a plurality of slits 2 are arranged in parallel so as to generate heat at most or a specific portion of a gas passage cross section, and a gas outflow side end face 7 is formed.
There is a method of forming a hole 8 so as not to reach the gas inflow end face 6 more. As shown by oblique lines in the plan view of FIG. 2A and the front view of FIG. 2B, these slits 2 and holes 8
A rapid heating portion is formed on the hole 8 near the gas inlet side end surface 6.
【００３２】 第２の手法の場合、後流側に配設するラ
イトオフ触媒の形状を、孔８に対応した凸状の形状にす
るなどして、図３のようにハニカムヒーター１００とラ
イトオフ触媒１０１をできる限り近接させて使用するこ
とができる。また、本手法では図２に示すような比較的
大きな孔８の代わりに、比較的小径の孔を、ガス流出側
端面よりガス流入側端面まで到達しないように設けるこ
とにより抵抗を調節し、急速加熱部が形成されるように
してもよい。また、孔を設ける代わりに、貫通孔の孔相
当直径、セル密度あるいは隔壁の厚さを部分的に変化さ
せたり、ハニカム構造体の隔壁（リブ部）に部分的にス
リット（途切れ）を設けることにより抵抗を調節し、急
速加熱部が形成されるようにしてもよい。In the case of the second method, the shape of the light-off catalyst disposed on the downstream side is changed to a convex shape corresponding to the hole 8, and the honeycomb heater 100 and the light-off catalyst are arranged as shown in FIG. The catalyst 101 can be used as close as possible. Also, in this method, instead of the relatively large hole 8 as shown in FIG. 2, a relatively small diameter hole is provided so as not to reach from the gas outflow side end face to the gas inflow side end face, so that resistance is adjusted, and A heating section may be formed. Instead of providing the holes, the hole equivalent diameter of the through holes, the cell density, or the thickness of the partition walls may be partially changed, or the slits (interruptions) may be partially provided in the partition walls (rib portions) of the honeycomb structure. , The resistance may be adjusted to form a rapid heating section.
【００３３】 なお、上記第１〜第２の手法は、組み合
わせて使うことができる。また、これらの手法は、単な
る一例であり、本発明においてはこれら以外にも急速加
熱部の面積がガス通過断面積の５〜５０％にすることが
できるような様々な抵抗調節手段を用いることができ
る。急速加熱部は、ガス通過断面の中央部に１つ設ける
ようにしても、複数点在するようにしてもよい。Note that the first and second methods can be used in combination. Also, these methods are merely examples, and in the present invention, in addition to these, use is made of various resistance adjusting means such that the area of the rapid heating section can be set to 5 to 50% of the gas passage sectional area. Can be. The rapid heating unit may be provided at a central portion of the gas passage section, or may be provided at a plurality of points.
【００３４】 本発明のハニカムヒーターは低電力型を
目的とするため、比較的小型のヒーターとすることが好
ましい。具体的には、ガス通過部分の体積は３０〜３０
０ｃｃ程度の大きさとする。３０ｃｃ未満の場合は、ヒ
ーターの機械的強度が問題となると同時に、ヒーター上
の触媒の有効面積が小さくなるので、そこから得られる
反応熱は小さくなり、所望の浄化能が得られない。逆に
３００ｃｃを超えると局所発熱型になるとはいえ、ヒー
ターの質量が大きくなるので、投入電力は大きなものと
なる。好ましいヒーター体積としては４０〜１５０ｃｃ
であり、ヒーターの搭載位置にも依存するが、３ｋＷ未
満の低電力で効果的に浄化できる。Since the honeycomb heater of the present invention aims at a low power type, it is preferable to use a relatively small heater. Specifically, the volume of the gas passage portion is 30 to 30
The size is about 0 cc. If it is less than 30 cc, the mechanical strength of the heater becomes a problem, and at the same time, the effective area of the catalyst on the heater becomes small, so that the reaction heat obtained therefrom becomes small and the desired purification ability cannot be obtained. Conversely, if it exceeds 300 cc, although it becomes a local heat generation type, since the mass of the heater becomes large, the input power becomes large. A preferable heater volume is 40 to 150 cc.
Although it depends on the mounting position of the heater, it can be effectively purified with low power of less than 3 kW.
【００３５】 なお、ここでいう「低電力」とは、（ワ
ット）×（時間）ができる限り小さいことを意味する
が、高ワットで短時間通電するよりも、低ワットで長時
間通電する方が好ましい。すなわち、高ワットで通電す
るためには、高電圧にするか、及び／又は高電流にする
必要があり、前者の場合、電源系とその制御システムが
煩雑となること、後者の場合、ケーブル等を異常に太く
する必要があることから、ガソリン車の場合、１２Ｖの
バッテリー電源と２００Ａ以下の電流になるよう調整す
ることが好ましい。この場合、バッテリーや制御システ
ム等の内部抵抗を考慮するとヒーターには２ｋＷ以下の
パワーが投入されることになる。電源については、バッ
テリー以外、オルタネーター、ウルトラキャパシターな
どが好適に使用できる。The term “low power” as used herein means that (watt) × (time) is as small as possible. Is preferred. That is, in order to energize at a high wattage, it is necessary to set a high voltage and / or a high current. In the former case, the power supply system and its control system are complicated, and in the latter case, cables and the like are used. In the case of a gasoline-powered vehicle, it is preferable to adjust the battery power to be 12 V and a current of 200 A or less. In this case, the power of 2 kW or less is applied to the heater in consideration of the internal resistance of the battery and the control system. As for the power source, other than a battery, an alternator, an ultracapacitor and the like can be suitably used.
【００３６】 ハニカムヒーターの長さについては、ハ
ニカムヒーターの断面積にも依存するが、一般には、６
〜４０ｍｍの長さのものを用いる。長さが６ｍｍ未満の
ものを用いると高温時のクリープによる変形が問題とな
り、一方、４０ｍｍを超えるとヒーター内部に発生する
熱応力による変形が問題となる。急速加熱部のガス流れ
方向の長さは、排ガス流入側端面から２５ｍｍ以内でヒ
ーターの長さと同じかそれ未満とする。２５ｍｍを超え
ると、急速加熱部の熱容量が大きくなるので、投入電力
の点で問題が発生する。ハニカムヒーターの隔壁の厚さ
は４０〜３００μｍ程度のもの、セル密度については１
５０〜６００セル／平方インチのものが好適に用いられ
る。The length of the honeycomb heater depends on the cross-sectional area of the honeycomb heater.
Use a length of ４０40 mm. If the length is less than 6 mm, deformation due to creep at high temperatures becomes a problem, while if it exceeds 40 mm, deformation due to thermal stress generated inside the heater becomes a problem. The length of the rapid heating section in the gas flow direction should be equal to or less than the length of the heater within 25 mm from the end face on the exhaust gas inflow side. If it exceeds 25 mm, the heat capacity of the rapid heating unit becomes large, so that a problem occurs in terms of input power. The thickness of the partition wall of the honeycomb heater is about 40 to 300 μm, and the cell density is 1
Those having 50 to 600 cells / square inch are preferably used.
【００３７】 上記した本発明のハニカムヒーターを用
いて、排ガス中の有害物質、特にコールドスタート時に
多量発生するＨＣを効率よく浄化するためには、コール
ドスタート時から２０秒以内に急速加熱部が触媒着火温
度に到達するように通電することが好ましい。In order to use the above-described honeycomb heater of the present invention to efficiently purify harmful substances in exhaust gas, in particular, HC generated in large quantities at the time of a cold start, the rapid heating part must be catalyzed within 20 seconds after the cold start. It is preferable to energize so as to reach the ignition temperature.
【００３８】 ヒーターへの通電方法としては、エンジ
ンクランク前に通電を開始するプレヒートと、エンジン
クランク直後に通電を開始するポストヒート、及びプレ
ヒートとポストヒートを組み合わせる方法など任意の方
法が可能であり、また通電は連続的又は間欠的に実施す
ることができる。制御システムの簡潔さより、ポストヒ
ートが好ましく、また、コールドスタート時に１回連続
的にパワーを投入する方法が好ましい。[0038] As a method of energizing the heater, any method such as a preheat in which energization is started before the engine crank, a postheat in which energization is started immediately after the engine crank, and a method of combining preheat and postheat can be used. In addition, energization can be performed continuously or intermittently. Post-heating is preferred because of the simplicity of the control system, and a method in which power is continuously applied once at the time of cold start is preferred.
【００３９】 急速加熱部の温度が５００℃以上にでき
るだけ早く到達することが好ましく、ＦＴＰ試験のＢａ
ｇ１において、２０秒以内（アイドリング時）に到達す
ることが一つの目安である。この時、急速加熱部の温度
の上限は１０００℃以下とすることが好ましい。１００
０℃を超えると低速加熱部との温度差によって発生した
熱応力により、ハニカムヒーターが変形や破損するおそ
れがある。It is preferable that the temperature of the rapid heating unit reaches 500 ° C. or more as quickly as possible.
In g1, one standard is to reach within 20 seconds (at the time of idling). At this time, it is preferable that the upper limit of the temperature of the rapid heating unit be 1000 ° C. or less. 100
If the temperature exceeds 0 ° C., the honeycomb heater may be deformed or damaged due to a thermal stress generated by a temperature difference from the low-speed heating unit.
【００４０】 本発明のようなハニカムヒーターを用い
て排ガス浄化システムを構成する場合、ハニカムヒータ
ーの後流側には、通常いわゆるライトオフ触媒やメイン
触媒が配設される。ハニカムヒーターは低電力で作動さ
せるために比較的小型のものを用いるので、それ自体で
コールドスタート時に排出される全ＨＣを浄化するには
不十分であり、通常比較的小型（０．２〜１．２ｌ程
度）のライトオフ触媒をハニカムヒーターの後流側に配
置する。更に、定常運転の時（例えばＢａｇ２）の浄化
能を向上させるためにはライトオフ触媒の後流側に比較
的大型（１〜３ｌ程度）のいわゆるメイン触媒を配置す
る。When an exhaust gas purification system is configured using a honeycomb heater as in the present invention, a so-called light-off catalyst or a main catalyst is usually provided downstream of the honeycomb heater. Since the honeycomb heater uses a relatively small one in order to operate with low power, it is not sufficient by itself to purify all HC discharged at the time of cold start, and is usually relatively small (0.2 to 1). .2 liters) of light-off catalyst is disposed downstream of the honeycomb heater. Further, in order to improve the purification performance during steady operation (for example, Bag2), a relatively large (about 1 to 3 l) so-called main catalyst is disposed downstream of the light-off catalyst.
【００４１】 これとは別の搭載方法としては、例えば
比較的小型（例えば０．２〜１．２ｌ程度）のライトオ
フ触媒を排ガス流路の最上流に配置し、次いでハニカム
ヒーターを配置し、更に後流にライトオフ触媒やメイン
触媒を配置する方法もある。この場合、ハニカムヒータ
ーへの投入電力の点では、最上流にハニカムヒーターを
配置する場合に比し、若干量多く必要となるが、最上流
のライトオフ触媒が熱衝撃緩衝材として作用するため、
ハニカムヒーターの耐久性の不安が解消される。As another mounting method, for example, a relatively small (for example, about 0.2 to 1.2 l) light-off catalyst is arranged at the uppermost stream of the exhaust gas channel, and then a honeycomb heater is arranged. Further, there is a method in which a light-off catalyst or a main catalyst is arranged downstream. In this case, in terms of the electric power supplied to the honeycomb heater, a slightly larger amount is required as compared with the case where the honeycomb heater is arranged at the uppermost stream, but since the light-up catalyst at the uppermost stream acts as a thermal shock buffer,
Anxiety about the durability of the honeycomb heater is eliminated.
【００４２】 なお、「ライトオフ触媒」、「メイン触
媒」とは俗称であり、要は内燃機関から排出される排ガ
スを浄化できる触媒をもった触媒体であればよく、通常
はセラミック質やメタル質からなるハニカム構造体に触
媒能をもつ触媒活性物質が触媒層として被覆担持された
構造体が一般に用いられる。Note that the terms “light-off catalyst” and “main catalyst” are common names, and in essence, may be any catalyst having a catalyst that can purify exhaust gas discharged from an internal combustion engine, and usually a ceramic or metal catalyst. Generally, a structure in which a catalytically active substance having a catalytic activity is coated and supported as a catalyst layer on a honeycomb structure made of a material is generally used.
【００４３】 ハニカムヒーターの搭載位置について
は、排気熱を活用できる点からエンジン排気孔近傍のい
わゆるマニホールド位置に搭載するのが好ましいが、こ
の場合、特に過酷な排ガス条件下に曝されることになる
ので、前述のとおり押し出し法によって調製されたハニ
カムヒーターが好適に用いられる。このようにマニホー
ルド位置に搭載した場合には、１ｋＷ以下の電力で好適
な浄化能を示す。With respect to the mounting position of the honeycomb heater, it is preferable to mount the honeycomb heater at a so-called manifold position near the engine exhaust hole from the viewpoint that exhaust heat can be utilized, but in this case, the honeycomb heater is exposed particularly under severe exhaust gas conditions. Therefore, the honeycomb heater prepared by the extrusion method as described above is preferably used. When mounted at the manifold position in this manner, a suitable purification ability is exhibited with an electric power of 1 kW or less.
【００４４】 なお、コールドスタート時は、通常燃料
リッチの状態で運転されるが、かかる状態ではハニカム
ヒーターがいかに急速に昇温されようとも、ＨＣの浄化
能は不十分であるため、二次空気を導入するか、エンジ
ンクランク後、燃料の量と空気の量を調節して、排ガス
組成をストイキオ近傍又は若干リーン側にシフトさせる
ような手法を用いることが好ましい。At the time of cold start, the fuel cell is normally operated in a fuel-rich state. However, in such a state, no matter how rapidly the temperature of the honeycomb heater is raised, the secondary air is not sufficiently purified because the HC purification ability is insufficient. It is preferable to use a method in which the amount of fuel and the amount of air are adjusted after the engine is cranked to shift the exhaust gas composition to the vicinity of stoichiometry or slightly to the lean side.
【００４５】[0045]
【実施例】 以下、本発明を実施例に基づいて更に詳細
に説明するが、本発明はこれらの実施例に限定されるも
のではない。EXAMPLES Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.
【００４６】〔ハニカムヒーターの調製〕 ヒーターＡ〜Ｃ：平均粒径４４μｍ以下のＦｅ粉末、Ｃ
ｒ−３０Ａｌ粉末（重量％）、Ｆｅ−５０Ａｌ粉末（重
量％）、Ｆｅ−２０Ｂ粉末（重量％）及びＹ2Ｏ3粉末を
Ｆｅ−１６Ｃｒ−８Ａｌ−０．０５Ｂ−０．５Ｙ2Ｏ3と
いう組成となるように添加、混合した。この混合物１０
０ｇあたり、メチルセルロース４ｇを有機バインダーと
して、また、オレイン酸１ｇを酸化防止剤として添加
し、混合した。このように坏土を調製した後、円柱形状
のハニカム成形体を押出成形により得た。このハニカム
成形体を大気中、９０℃で１６時間乾燥した後、水素雰
囲気下で１３２５℃に２時間保持して焼結した。次い
で、空気中、１１５０℃で３０分間、熱処理を行った。[Preparation of Honeycomb Heaters] Heaters A to C: Fe powder having an average particle size of 44 μm or less, C
r-30Al powder (wt%), Fe-50Al powder (wt%), Fe-20B powder (% by weight) and that Y 2 O 3 powder Fe-16Cr-8Al-0.05B- 0.5Y 2 O 3 The components were added and mixed to obtain the composition. This mixture 10
Per 0 g, 4 g of methylcellulose was added as an organic binder, and 1 g of oleic acid was added as an antioxidant and mixed. After preparing the kneaded clay in this way, a cylindrical honeycomb formed body was obtained by extrusion molding. After drying this honeycomb formed body at 90 ° C. for 16 hours in the air, it was sintered at 1325 ° C. for 2 hours in a hydrogen atmosphere. Next, heat treatment was performed in air at 1150 ° C. for 30 minutes.
【００４７】 上記方法により外径９３ｍｍφ、厚さ１
２ｍｍ、隔壁厚さ０．１ｍｍ、六角セルよりなるセル密
度が４５０セル／平方インチのハニカム構造体を得た。
なお、このハニカム構造体の多孔度は２％（ほぼ非多孔
質）で、表層にはＡｌ2Ｏ3質の保護層が形成されてい
た。このハニカム構造体に前述した第１の手法を用いて
スリットを配設し、その中心部を急速加熱できるように
した。According to the above method, the outer diameter is 93 mmφ and the thickness is 1
A honeycomb structure having a cell density of 450 cells / square inch consisting of 2 mm, a partition wall thickness of 0.1 mm, and hexagonal cells was obtained.
The porosity of this honeycomb structure was 2% (substantially non-porous), and an Al 2 O 3 protective layer was formed on the surface layer. A slit was provided in this honeycomb structure using the first method described above, so that the central portion could be rapidly heated.
【００４８】 スリットを形成した後、γ−Ａｌ2Ｏ3と
ＣｅＯ2とが重量比で７０：３０となるように、両者の
粉末を調製し、これらの粉末に水と微量の硝酸を添加
し、湿式法で粉砕して、担持スラリーを調製した。この
担持スラリーを用い、ディップ法により、ウォッシュコ
ート層を形成した。次いで、このウォッシュコート層を
乾燥した後、５００℃で焼成し、γ−Ａｌ2Ｏ3とＣｅＯ
2とを被覆した。ついで、ＰｄとＰｔとＲｈとをモル比
で６：５：１となり、かつ、総担持量が８０ｇ／ｆｔ3
になるように、硝酸パラジウムと塩化白金酸と硝酸ロジ
ウムとからなる水溶液に、約２０分含浸させ、触媒組成
物を担持した。After forming the slits, both powders were prepared so that the weight ratio of γ-Al 2 O 3 and CeO 2 was 70:30, and water and a small amount of nitric acid were added to these powders. Then, the mixture was pulverized by a wet method to prepare a supported slurry. Using this supported slurry, a washcoat layer was formed by a dipping method. Next, after drying this wash coat layer, it is baked at 500 ° C., and γ-Al 2 O 3 and CeO
2 was coated. Next, the molar ratio of Pd, Pt, and Rh was 6: 5: 1, and the total supported amount was 80 g / ft 3.
Was impregnated with an aqueous solution comprising palladium nitrate, chloroplatinic acid and rhodium nitrate for about 20 minutes to carry the catalyst composition.
【００４９】 次いで、外周上に２箇所電極ボルトを溶
接しハニカムヒーターとした。このハニカムヒーターの
外周部を絶縁材を介して、金属質の缶体で保持した。ガ
ス通過径はリテーナーによって８２ｍｍに絞りこまれ
た。以上のようにして、急速加熱部の面積がそれぞれガ
ス通過断面積の１０％（ヒーターＡ）、２５％（ヒータ
ーＢ）、５０％（ヒーターＣ）である３種のハニカムヒ
ーターを得た。Next, electrode bolts were welded at two places on the outer periphery to obtain a honeycomb heater. The outer peripheral portion of the honeycomb heater was held by a metal can through an insulating material. The gas passage diameter was reduced to 82 mm by a retainer. As described above, three types of honeycomb heaters were obtained in which the area of the rapid heating portion was 10% (heater A), 25% (heater B), and 50% (heater C) of the gas passage cross-sectional area, respectively.
【００５０】ヒーターＤ：前述した第２の手法を用い
て、ハニカム構造体の中心部に直径２．１ｍｍ、深さ６
ｍｍの孔をガス流出側端面から配設し、次いでスリット
を８本配設し、孔を配設した箇所が急速加熱部となるよ
うなハニカムヒーターを調製した。なお、急速加熱部の
面積はガス通過断面積の２５％であった。ハニカム構造
体の作製、触媒組成物の担持、缶体による保持等は上記
ヒーターＡ〜Ｃと同様にして行った。Heater D: Using the above-described second method, the center of the honeycomb structure was 2.1 mm in diameter and 6 mm in depth.
A hole having a diameter of 1 mm was provided from the end face on the gas outflow side, then eight slits were provided, and a honeycomb heater was prepared such that the portion where the holes were provided became a rapid heating portion. The area of the rapid heating section was 25% of the gas passage cross-sectional area. Preparation of the honeycomb structure, support of the catalyst composition, holding by the can, and the like were performed in the same manner as in the heaters A to C.
【００５１】ヒーターＥ：ヒーターＡ〜Ｃと同様の調製
方法でガス通過部の断面ほぼ全部（９０％）が均一に発
熱する全体発熱型のハニカムヒーターを調製した。Heater E: By the same preparation method as in heaters A to C, an entire heat generation type honeycomb heater in which substantially the entire cross section (90%) of the gas passage section uniformly generates heat was prepared.
【００５２】ヒーターＦ：ハニカム構造体の厚さを１／
２（６ｍｍ）とした以外は上記ヒーターＥと同様にし
て、ガス通過部の断面ほぼ全部（９０％）が均一に発熱
する全体発熱型のハニカムヒーターを調製した。Heater F: The thickness of the honeycomb structure was reduced by 1 /
Except that the thickness was 2 (6 mm), a whole heat generation type honeycomb heater in which substantially all (90%) of the cross section of the gas passage section uniformly generated heat was prepared in the same manner as the heater E.
【００５３】〔ＦＴＰ試験〕上記のようにして得られた
ヒーターＡ〜Ｆを用い、その直後に０．９ｌのライトオ
フ触媒を、さらに後流側に１．７ｌのメイン触媒を配置
して、図４、図５に示す２種の排気システム（Manifold
System及びUndertoe System）を構成した。図中の符号
１００はハニカムヒーター、１０１はライトオフ触媒、
１０２はメイン触媒、１０３はエンジンをそれぞれ示し
ている。エンジンは排気量２０００ｃｃ、Ｌ４型のもの
を用いた。また、ハニカムヒーター、ライトオフ触媒、
メイン触媒はすべて、入口温度が８５０℃のストイキオ
の排ガスにさらし、１分毎に５秒間燃料カットされたモ
ードで加速耐久して、劣化させたものを用いた。[FTP test] Using the heaters A to F obtained as described above, immediately after that, 0.9 l of a light-off catalyst and further 1.7 l of a main catalyst on the downstream side were arranged. The two types of exhaust systems (Manifold) shown in FIGS.
System and Undertoe System). In the figure, reference numeral 100 denotes a honeycomb heater, 101 denotes a light-off catalyst,
102 denotes a main catalyst, and 103 denotes an engine. The engine used was an L4 type engine with a displacement of 2000 cc. Also, honeycomb heater, light-off catalyst,
All of the main catalysts were used after being exposed to stoichiometric exhaust gas having an inlet temperature of 850 ° C., subjected to accelerated durability in a mode in which fuel was cut every minute for 5 seconds, and deteriorated.
【００５４】 表１に示す条件で、ＦＴＰ（Federal Te
st Procedure）に準じてＢａｇエミッションを測定し、
実施例１〜５及び比較例１〜４の各々のコールドスター
ト特性を評価した。なお、この測定に際しては、ハニカ
ムヒーターの上流側から二次空気を１２０ｌ／ｍｉｎで
エンジン始動時から１００秒間導入した。また、通電は
定電圧発生装置を用い、所定のｋＷになるよう電圧を調
整した。通電時間はエンジンクランク後から３０秒間と
した。Under the conditions shown in Table 1, FTP (Federal Te
st Procedure), measure Bag emissions,
The cold start characteristics of each of Examples 1 to 5 and Comparative Examples 1 to 4 were evaluated. In this measurement, secondary air was introduced from the upstream side of the honeycomb heater at 120 l / min for 100 seconds from the start of the engine. The voltage was adjusted to a predetermined kW by using a constant voltage generator for energization. The energization time was 30 seconds after the engine crank.
【００５５】[0055]
【表１】 [Table 1]
【００５６】[0056]
【発明の効果】 以上説明したように、本発明によれ
ば、少ない電力で、内燃機関から排出される排ガス中の
有害成分、特にコールドスタート時に大量発生するＨＣ
を効率よく浄化することができる。As described above, according to the present invention, harmful components in exhaust gas discharged from an internal combustion engine with a small amount of electric power, in particular, a large amount of HC generated during a cold start.
Can be efficiently purified.
【図１】 本発明の実施態様の一例を示す説明図であ
る。FIG. 1 is an explanatory diagram showing an example of an embodiment of the present invention.
【図２】 本発明の実施態様の一例を示す説明図であ
る。FIG. 2 is an explanatory diagram showing an example of an embodiment of the present invention.
【図３】 本発明のヒーターとライトオフ触媒との配置
方法の一例を説明するための断面図である。FIG. 3 is a cross-sectional view for explaining an example of an arrangement method of a heater and a light-off catalyst according to the present invention.
【図４】 実施例においてヒーターの性能を評価するた
めに用いたシステム（Manifold System）の概要図であ
る。FIG. 4 is a schematic diagram of a system (Manifold System) used to evaluate the performance of the heater in the example.
【図５】 実施例においてヒーターの性能を評価するた
めに用いたシステム（Undertoe System）の概要図であ
る。FIG. 5 is a schematic diagram of a system (Undertoe System) used to evaluate the performance of the heater in the example.
１…ハニカム構造体、２…スリット、５…電極、６…ガ
ス流入側端面、７…ガス流出側端面、１００…ハニカム
ヒーター、１０１…ライトオフ触媒、１０２…メイン触
媒、１０３…エンジン。DESCRIPTION OF SYMBOLS 1 ... Honeycomb structure, 2 ... Slit, 5 ... Electrode, 6 ... Gas inlet side end face, 7 ... Gas outlet side end face, 100 ... Honeycomb heater, 101 ... Light-off catalyst, 102 ... Main catalyst, 103 ... Engine.
Claims (15)
ス流れ方向に実質的に平行な多数の貫通孔を有し、ガス
流入側及びガス流出側の両端面を有するハニカム構造体
と、該ハニカム構造体に設けられた通電のための少なく
とも２つの電極とを含むハニカムヒーターであって、前
記隔壁上には触媒層が被覆担持され、通電時に少なくと
もガス流入側端面近傍を含む特定の領域が、他の領域に
比して局所的に急速加熱できるよう抵抗が調節され、か
つ前記局所的に急速加熱される特定の領域の面積がガス
通過断面積の５〜５０％の範囲にあることを特徴とする
ハニカムヒーター。1. A honeycomb structure having a plurality of through-holes substantially parallel to a gas flow direction partitioned by a partition wall made of a conductive material, and having both end faces on a gas inflow side and a gas outflow side; A honeycomb heater including at least two electrodes for energization provided in a honeycomb structure, wherein a catalyst layer is coated and supported on the partition walls, and a specific region including at least a gas inflow side end face near the partition when energization is performed. The resistance is adjusted so that rapid heating can be performed locally compared to other regions, and the area of the specific region which is rapidly heated is in the range of 5 to 50% of the gas passage cross-sectional area. Features honeycomb heater.
も１本のスリットからなる請求項１記載のハニカムヒー
ター。2. The honeycomb heater according to claim 1, wherein the means for adjusting the resistance comprises at least one slit.
方向に垂直に伸びた、少なくとも１つの孔からなる請求
項１記載のハニカムヒーター。3. The honeycomb heater according to claim 1, wherein the means for adjusting the resistance comprises at least one hole extending perpendicular to the gas flow direction.
孔相当直径を部分的に変化させたものである請求項１記
載のハニカムヒーター。4. The honeycomb heater according to claim 1, wherein the means for adjusting the resistance is obtained by partially changing an equivalent diameter of the through hole.
さを部分的に変化させたものである請求項１記載のハニ
カムヒーター。5. The honeycomb heater according to claim 1, wherein the means for adjusting the resistance is obtained by partially changing the thickness of the partition.
セル密度を部分的に変化させたものである請求項１記載
のハニカムヒーター。6. The honeycomb heater according to claim 1, wherein the means for adjusting the resistance is obtained by partially changing the cell density of the through hole.
構造体の隔壁に部分的にスリットを設けたものである請
求項１記載のハニカムヒーター。7. The honeycomb heater according to claim 1, wherein the means for adjusting the resistance is formed by partially providing a slit in a partition wall of the honeycomb structure.
ガス通過断面の中央部にある請求項１ないし７のいずれ
かに記載のハニカムヒーター。8. The specific area which is rapidly heated locally,
The honeycomb heater according to any one of claims 1 to 7, which is located at a central portion of a gas passage section.
ガス通過断面に点在している請求項１ないし７のいずれ
かに記載のハニカムヒーター。9. The specific area that is locally rapidly heated,
The honeycomb heater according to any one of claims 1 to 7, which is scattered in a gas passage section.
ガス流れ方向に実質的に平行な多数の貫通孔を有し、ガ
ス流入側及びガス流出側の両端面を有するハニカム構造
体と、該ハニカム構造体に設けられた通電のための少な
くとも２つの電極とを含むハニカムヒーターであって、
前記隔壁上には触媒層が被覆担持され、前記ハニカム構
造体には、ガス通過断面の大部分又は特定の部分を発熱
するように、複数かつ平行にスリットが配設され、更に
少なくともガス流入側端面近傍を含む特定の領域が他の
領域に比して局所的に急速加熱できるように、ガス流出
側端面より少なくとも１つの孔がガス流入側端面まで到
達しないよう配設され、かつ前記局所的に急速加熱され
る特定の領域の面積がガス通過断面積の５〜５０％の範
囲にあることを特徴とするハニカムヒーター。10. A honeycomb structure having a large number of through-holes substantially parallel to a gas flow direction partitioned by a partition wall made of a conductive material, and having both end faces on a gas inflow side and a gas outflow side; A honeycomb heater including at least two electrodes for energization provided in the honeycomb structure,
A catalyst layer is coated and supported on the partition walls, and the honeycomb structure is provided with a plurality of and parallel slits so as to generate heat in most or a specific portion of a gas passage section, and further, at least on a gas inflow side. At least one hole is disposed so that at least one hole does not reach the gas inflow side end surface from the gas outflow side end surface so that a specific region including the vicinity of the end surface can be locally heated more rapidly than other regions, and Wherein the area of the specific region which is rapidly heated is in the range of 5 to 50% of the gas passage sectional area.
ガス流れ方向に実質的に平行な多数の貫通孔を有し、ガ
ス流入側及びガス流出側の両端面を有するハニカム構造
体と、該ハニカム構造体に設けられた通電のための少な
くとも２つの電極とを含むハニカムヒーターであって、
前記隔壁上には触媒層が被覆担持され、前記ハニカム構
造体には、ガス通過断面の大部分又は特定の部分を発熱
するように、複数かつ平行にスリットが配設され、更に
少なくともガス流入側端面近傍を含む特定の領域が他の
領域に比して局所的に急速加熱できるように、前記貫通
孔の孔相当直径を部分的に変化させ、かつ前記局所的に
急速加熱される特定の領域の面積がガス通過断面積の５
〜５０％の範囲にあることを特徴とするハニカムヒータ
ー。11. A honeycomb structure having a large number of through-holes substantially parallel to a gas flow direction partitioned by a partition wall made of a conductive material, and having both end faces on a gas inflow side and a gas outflow side. A honeycomb heater including at least two electrodes for energization provided in the honeycomb structure,
A catalyst layer is coated and supported on the partition walls, and the honeycomb structure is provided with a plurality of and parallel slits so as to generate heat in most or a specific portion of a gas passage section, and further, at least on a gas inflow side. In order that a specific area including the vicinity of an end face can be locally rapidly heated as compared with another area, the hole equivalent diameter of the through hole is partially changed, and the specific area which is locally heated rapidly. Area is 5 of the gas passage cross section
A honeycomb heater characterized by being in the range of 50% to 50%.
ガス流れ方向に実質的に平行な多数の貫通孔を有し、ガ
ス流入側及びガス流出側の両端面を有するハニカム構造
体と、該ハニカム構造体に設けられた通電のための少な
くとも２つの電極とを含むハニカムヒーターであって、
前記隔壁上には触媒層が被覆担持され、前記ハニカム構
造体には、ガス通過断面の大部分又は特定の部分を発熱
するように、複数かつ平行にスリットが配設され、更に
少なくともガス流入側端面近傍を含む特定の領域が他の
領域に比して局所的に急速加熱できるように、前記隔壁
の厚さを部分的に変化させ、かつ前記局所的に急速加熱
される特定の領域の面積がガス通過断面積の５〜５０％
の範囲にあることを特徴とするハニカムヒーター。12. A honeycomb structure having a plurality of through-holes substantially parallel to a gas flow direction partitioned by a partition wall made of a conductive material and having both end faces on a gas inflow side and a gas outflow side. A honeycomb heater including at least two electrodes for energization provided in the honeycomb structure,
A catalyst layer is coated and supported on the partition walls, and the honeycomb structure is provided with a plurality of and parallel slits so as to generate heat in most or a specific portion of a gas passage section, and further, at least on a gas inflow side. The thickness of the partition wall is partially changed so that a specific region including the vicinity of the end face can be locally rapidly heated as compared with other regions, and an area of the specific region which is rapidly heated locally Is 5 to 50% of the gas cross-sectional area
Honeycomb heater characterized in that:
ガス流れ方向に実質的に平行な多数の貫通孔を有し、ガ
ス流入側及びガス流出側の両端面を有するハニカム構造
体と、該ハニカム構造体に設けられた通電のための少な
くとも２つの電極とを含むハニカムヒーターであって、
前記隔壁上には触媒層が被覆担持され、前記ハニカム構
造体には、ガス通過断面の大部分又は特定の部分を発熱
するように、複数かつ平行にスリットが配設され、更に
少なくともガス流入側端面近傍を含む特定の領域が他の
領域に比して局所的に急速加熱できるように、前記貫通
孔のセル密度を部分的に変化させ、かつ前記局所的に急
速加熱される特定の領域の面積がガス通過断面積の５〜
５０％の範囲にあることを特徴とするハニカムヒータ
ー。13. A honeycomb structure having a plurality of through-holes substantially parallel to a gas flow direction partitioned by a partition wall made of a conductive material and having both end faces on a gas inflow side and a gas outflow side. A honeycomb heater including at least two electrodes for energization provided in the honeycomb structure,
A catalyst layer is coated and supported on the partition walls, and the honeycomb structure is provided with a plurality of and parallel slits so as to generate heat in most or a specific portion of a gas passage section, and further, at least on a gas inflow side. The cell density of the through-hole is partially changed so that a specific region including the vicinity of the end face can be locally rapidly heated as compared with other regions, and the specific region to be rapidly heated locally is The area is 5 to 5
A honeycomb heater characterized by being in a range of 50%.
ガス流れ方向に実質的に平行な多数の貫通孔を有し、ガ
ス流入側及びガス流出側の両端面を有するハニカム構造
体と、該ハニカム構造体に設けられた通電のための少な
くとも２つの電極とを含むハニカムヒーターであって、
前記隔壁上には触媒層が被覆担持され、前記ハニカム構
造体には、ガス通過断面の大部分又は特定の部分を発熱
するように、複数かつ平行にスリットが配設され、更に
少なくともガス流入側端面近傍を含む特定の領域が他の
領域に比して局所的に急速加熱できるように、前記ハニ
カム構造体の隔壁に部分的にスリットが設けられ、かつ
前記局所的に急速加熱される特定の領域の面積がガス通
過断面積の５〜５０％の範囲にあることを特徴とするハ
ニカムヒーター。14. A honeycomb structure having a plurality of through-holes substantially parallel to a gas flow direction partitioned by a partition wall made of a conductive material and having both end faces on a gas inflow side and a gas outflow side; A honeycomb heater including at least two electrodes for energization provided in the honeycomb structure,
A catalyst layer is coated and supported on the partition walls, and the honeycomb structure is provided with a plurality of and parallel slits so as to generate heat in most or a specific portion of a gas passage section, and further, at least on a gas inflow side. Slits are partially provided in the partition walls of the honeycomb structure, and the specific region which is locally rapidly heated, so that a specific region including the vicinity of the end face can be locally rapidly heated as compared with other regions. A honeycomb heater, wherein the area of the region is in the range of 5 to 50% of the gas passage sectional area.
ガス流れ方向に実質的に平行な多数の貫通孔を有し、ガ
ス流入側及びガス流出側の両端面を有するハニカム構造
体と、該ハニカム構造体に設けられた通電のための少な
くとも２つの電極とを含むハニカムヒーターであって、
前記隔壁上には触媒層が被覆担持され、通電時に少なく
ともガス流入側端面近傍を含む特定の領域が、他の領域
に比して局所的に急速加熱できるよう抵抗が調節され、
かつ前記局所的に急速加熱される特定の領域の面積がガ
ス通過断面積の５〜５０％の範囲にあるハニカムヒータ
ーを用いて、コールドスタート時から２０秒以内に前記
局所的に急速加熱される特定の領域が触媒着火温度に到
達するように通電することを特徴とするハニカムヒータ
ーの運転方法。15. A honeycomb structure having a plurality of through-holes substantially parallel to a gas flow direction partitioned by a partition wall made of a conductive material, and having both end faces on a gas inflow side and a gas outflow side. A honeycomb heater including at least two electrodes for energization provided in the honeycomb structure,
A catalyst layer is coated and supported on the partition walls, and a specific area including at least a gas inflow side end surface near the gas inflow side is energized so that the resistance can be rapidly increased locally compared to other areas,
In addition, using the honeycomb heater in which the area of the specific region to be rapidly heated is in the range of 5 to 50% of the gas passage cross-sectional area, the locally rapid heating is performed within 20 seconds after the cold start. A method for operating a honeycomb heater, wherein current is supplied so that a specific region reaches a catalyst ignition temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001077716A JP2001252573A (en) | 2001-03-19 | 2001-03-19 | Honeycomb heater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001077716A JP2001252573A (en) | 2001-03-19 | 2001-03-19 | Honeycomb heater |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP31375393A Division JP3210508B2 (en) | 1993-12-14 | 1993-12-14 | Honeycomb heater |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2001252573A true JP2001252573A (en) | 2001-09-18 |
Family
ID=18934430
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2001077716A Pending JP2001252573A (en) | 2001-03-19 | 2001-03-19 | Honeycomb heater |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2001252573A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011230971A (en) * | 2010-04-28 | 2011-11-17 | Denso Corp | Joined body and method for producing the same |
| WO2012086814A1 (en) * | 2010-12-24 | 2012-06-28 | 日本碍子株式会社 | Honeycomb structure |
-
2001
- 2001-03-19 JP JP2001077716A patent/JP2001252573A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011230971A (en) * | 2010-04-28 | 2011-11-17 | Denso Corp | Joined body and method for producing the same |
| WO2012086814A1 (en) * | 2010-12-24 | 2012-06-28 | 日本碍子株式会社 | Honeycomb structure |
| CN103282102A (en) * | 2010-12-24 | 2013-09-04 | 日本碍子株式会社 | Honeycomb structure |
| JP5850858B2 (en) * | 2010-12-24 | 2016-02-03 | 日本碍子株式会社 | Honeycomb structure |
| US9585196B2 (en) | 2010-12-24 | 2017-02-28 | Ngk Insulators, Ltd. | Honeycomb structure |
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|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20050125 |