JP3679376B2

JP3679376B2 - Method for manufacturing exhaust treatment apparatus for holding columnar body through buffer member in cylindrical member

Info

Publication number: JP3679376B2
Application number: JP2002075723A
Authority: JP
Inventors: 入江　　徹; 彰信森川
Original assignee: Sango Co Ltd
Current assignee: Sango Co Ltd
Priority date: 2001-04-18
Filing date: 2002-03-19
Publication date: 2005-08-03
Anticipated expiration: 2022-03-19
Also published as: JP2003003837A

Description

【０００１】
【発明の属する技術分野】
本発明は、筒状部材内に緩衝部材を介して柱体を保持する排気処理装置の製造方法に関し、例えば、筒状部材内に緩衝マットを介して触媒担体を保持する触媒コンバータの製造方法として好適な製造方法に係る。
【０００２】
【従来の技術】
近時の自動車には触媒コンバータが搭載されており、その製造方法としては、触媒担体の外周に緩衝部材としてセラミック製の緩衝マットを巻回し、緩衝マットを圧縮しながらケーシング（筒状部材）内に圧入する方法が一般的である。
【０００３】
例えば、内燃機関の触媒コンバータの製造方法に関し、図１１に示すように、触媒担体２０の外周に緩衝部材としてセラミック製の緩衝マット３０を巻回し、これらを筒状部材４０内に収容する方法が知られている。この場合において、緩衝マット３０を圧縮しながら筒状部材４０の一方の開口から圧入する方法（圧入方式）が一般的であり、筒状部材４０の一方の開口に環状の挿入治具１００が嵌合され、これを介して触媒担体２０及び緩衝マット３０が圧入される。挿入治具１００は剛体（例えば金属製）で、緩衝マット３０の挿入を容易にするため、また筒状部材４０の径のバラつきを吸収するために、図１２に拡大して示すように、所定距離ｇだけ筒状部材４０の内側に突出（オーバーハング）する構造とされる。従って、挿入治具１００の開口部の内径が筒状部材４０の内径より２ｇだけ小径となり、触媒担体２０及び緩衝マット３０を圧入する際には、この突出部が実質的に最小径部となる。
【０００４】
従って、触媒担体２０及び緩衝マット３０を筒状部材４０内に圧入するときに過剰に圧縮されて何れかが破損されることを回避するため、緩衝マット３０の圧縮量は、これらが挿入治具１００の突出部を通過し得る程度の小さい値に設定せざるを得ない。しかし、この結果、圧入後の緩衝マット３の圧縮量が不足することになり、触媒担体２０を確実に保持することが困難となる。
【０００５】
また、圧入方式の欠点として、触媒担体の外径のバラつき（誤差）と筒状部材の外径のバラつき（誤差）を吸収することができず、これらの誤差が相乗的に作用し、圧入状態での触媒担体の保持が不確かなものとなるという問題がある。これを解決するには触媒担体と筒状部材の外径のバラつきを相殺するような最適組合せを選択すればよいが、量産工程においては対応困難であり、また最適組合せが存在するとは限らない。
【０００６】
上記の挿入治具を用いた圧入方式の触媒コンバータの組付方法に関し、特公昭６０−２４２８６号公報には、触媒担体ケーシング主体内挿入に際しては、その触媒担体を被覆するクッション体を先ず挿入治具の挿入孔により半径方向に一次圧縮してケーシング主体の大径部内に挿入し、次いでその一次圧縮後のクッション体をケーシング主体の傾斜段部により半径方向に段階的に二次圧縮してケーシング主体の中央部内に挿入する方法が提案されている。このとき、挿入孔最小内径はケーシング主体の大径部内径よりも小さく設定されているので、クッション体のケーシング主体内への挿入を、ケーシング主体の端面に邪魔されることなくスムーズに行なわせることができ、また挿入孔最小内径はケーシング主体の中央部内径よりも大きく設定されているので、挿入治具によってはクッション体が半径方向に過圧縮されることはないとしている。
【０００７】
【発明が解決しようとする課題】
然し乍ら、上記特公昭６０−２４２８６号公報に記載の触媒コンバータの組付方法においては、ケーシング主体１の両開口端に出口９、あるいは入口１０を開口した載頭円錐形状の端末ケース１１，１２を溶着して触媒コンバータの組付を完了すると記載されているように、ケーシング主体の両端部に端末ケースが溶着されるように構成されており、ケーシング主体と端末ケースが一体的に形成されるものではない。従って、クッション体のケーシング主体内への挿入時の問題は解決されるものの、端末ケースとの溶着工程が必須であり、その接合部の処理も必要となる。このように、上記公報に記載の触媒コンバータは部品点数が多いというだけでなく、触媒コンバータの製造方法としては容易な方法ではない。
【０００８】
更に、触媒コンバータに限らず、例えば筒状部材内に緩衝部材を介してディーゼル・パティキュレート・フィルタ（ＤＰＦ）を保持するＤＰＦ装置等においても、上記と同様の問題が顕在化している。而して、筒状部材内に緩衝部材を介して脆弱な柱体を保持する装置の適切な製造方法が要請されている。
【０００９】
そこで、本発明は、筒状部材内に緩衝部材を介して柱体を保持する排気処理装置の製造方法において、筒状部材内に柱体及び緩衝部材を容易且つ適切に圧入して確実に保持すると共に、この保持部から開口端に向けて滑らかな面で連続するボトルネック部を容易に一体的に形成し得るようにすることを課題とする。
【００１０】
【課題を解決するための手段】
上記課題を解決するため、本発明は、請求項１に記載のように、筒状部材内に緩衝部材を介して柱体を保持する排気処理装置の製造方法において、前記筒状部材が前記柱体の断面より大きく軸方向に略均等断面の中空部を有し、前記筒状部材の軸方向の所定範囲の断面を縮小加工して、前記柱体の断面の外側に所定幅を加えた断面の中空部を有する保持部を形成すると共に、該保持部に連続して少くとも一方の開口端側に向かって断面が漸次拡大するテーパ部を形成し、該テーパ部から前記開口端に至るまで、前記筒状部材の元の寸法を維持するように形成し、且つ、前記柱体の周囲に前記緩衝部材を巻回した後、前記柱体及び前記緩衝部材を前記筒状部材の前記開口端から前記テーパ部でガイドしつつ前記筒状部材の保持部に圧入して前記筒状部材内に保持し、前記筒状部材のテーパ部から前記開口端に至るまでの端部に対し、該端部の外周回りを同径の円形軌跡にて公転すると共に前記端部の径方向に移動する複数のスピニングローラを前記端部の軸に沿って移動させてスピニング加工を行ない、前記開口端側に向かって前記端部の断面を漸次縮小加工し前記テーパ部を除去してボトルネック部を形成することとしたものである。
【００１１】
上記の製造方法において、製造対象の装置としては、例えば、触媒コンバータやディーゼル排気処理装置といった排気処理装置がある。筒状部材は外筒あるいはハウジングとも呼ばれ、触媒コンバータの場合には、柱体は触媒担体に対応し、緩衝部材は触媒担体用の緩衝マットに対応する。また、ディーゼル排気処理装置の場合には、柱体はディーゼル・パティキュレート・フィルタ（ＤＰＦ）に対応し、緩衝部材はＤＰＦ用の緩衝マットに対応する。柱体を構成する触媒担体及びＤＰＦは一般的には円柱状又は円筒状に形成され、円形断面を有するが、楕円や長円などの非円形断面を有するものもあり、本願の請求項１における柱体には、これら非円形断面のものも包含される。尚、保持部の縮径加工は、以下のようにスピニング加工によって行なうことができるが、他の縮径装置を用いることとしてもよい。
【００１２】
特に、上記の製造方法において、請求項２に記載のように、前記筒状部材の軸方向の所定範囲を、前記筒状部材の外周回りを同径の円形軌跡にて公転すると共に前記筒状部材の径方向に移動する複数のスピニングローラを前記筒状部材の軸に沿って移動させてスピニング加工を行ない、前記筒状部材の軸方向の所定範囲を縮径して前記保持部を形成すると共に、前記保持部に連続してテーパ面が前記筒状部材の軸に対し２度乃至６度の傾斜角度となるように前記テーパ部を形成することとしてもよい。この場合には、例えば、前記筒状部材の両端を固定した状態で、前記筒状部材に対し前記スピニング加工を行なうように構成するとよい。
【００１３】
あるいは、請求項３に記載のように、筒状部材内に緩衝部材を介して柱体を保持する排気処理装置の製造方法において、前記筒状部材が前記柱体の断面より大きく軸方向に略均等断面の中空部を有し、前記筒状部材の軸方向の所定範囲の断面を縮小加工し、前記柱体の断面の外側に所定幅を加えた断面の中空部を有する保持部を形成し、該保持部から前記筒状部材の一方の開口端に至るまでの第１の端部の断面を漸次縮小加工して第１のボトルネック部を形成すると共に、前記保持部に連続して前記筒状部材の他方の開口端側に向かって断面が漸次拡大するテーパ部を形成し、該テーパ部から前記他方の開口端に至るまで、前記筒状部材の元の寸法を維持するように形成し、且つ、前記柱体の周囲に前記緩衝部材を巻回した後、前記柱体及び前記緩衝部材を前記他方の開口端から前記テーパ部でガイドしつつ前記筒状部材の保持部に圧入して前記筒状部材内に保持し、前記筒状部材のテーパ部から前記他方の開口端に至るまでの第２の端部に対し、該第２の端部の外周回りを同径の円形軌跡にて公転すると共に前記端部の径方向に移動する複数のスピニングローラを前記第２の端部の軸に沿って移動させてスピニング加工を行ない、前記筒状部材の他方の開口端側に向かって断面を漸次縮小加工し前記テーパ部を除去して第２のボトルネック部を形成することとしてもよい。
【００１４】
更に、上記の製造方法において、請求項４に記載のように、前記筒状部材の軸方向の所定位置から前記筒状部材の一方の開口端側に向かって、前記筒状部材の外周回りを同径の円形軌跡にて公転すると共に前記筒状部材の径方向に移動する複数のスピニングローラを前記筒状部材の軸に沿って移動させてスピニング加工を行ない、前記筒状部材のテーパ部を形成すると共に前記保持部を形成し、且つ該保持部から前記一方の開口端に至るまでの第１の端部に対し、該第１の端部の外周回りを同径の円形軌跡にて公転すると共に前記第１の端部の径方向に移動する複数のスピニングローラを前記第１の端部の軸に沿って移動させてスピニング加工を行ない、前記第１のボトルネック部を形成すると共に、前記保持部に連続してテーパ面が前記筒状部材の軸に対し２度乃至６度の傾斜角度となるように前記テーパ部を形成することとしてもよい。
【００１５】
尚、上記の製造方法において、予め前記柱体の外径を測定し、該測定結果に所定値を加えた径を最適外径として、該最適外径に基づき前記保持部を形成することとしてもよい。これにより、測定を含め、一工程中で連続して行なうことができる。また、筒状部材内には、上記の柱体及び緩衝部材に加え、他の構成部品を収容し、筒状部材に圧入することとしてもよい。
【００１６】
【発明の実施の形態】
上記の筒状部材内に緩衝部材を介して柱体を保持する排気処理装置の製造方法において、その具体的一態様として触媒コンバータの製造方法について図面を参照して説明する。図１の上方に示すように、本発明の柱体を構成する触媒担体２の外周に、本発明の緩衝部材たる緩衝マット３が巻回され、必要に応じ可燃性テープ等によって固定される。尚、本実施形態においては、触媒担体２はセラミックスで構成されているが、金属製でもよい。緩衝マット３は、本実施形態では熱による膨張が殆どないアルミナマットで構成されているが、熱膨張型のバーミキュライト式の緩衝マットを用いることとしてもよい。また、金属細線を編成したワイヤメッシュ等を用いてもよいし、それをセラミックマットと組み合わせて使用してもよい。更に、それらと金属円環状のリテーナを組み合わせてもよい。
【００１７】
本実施形態の製造方法においては、先ず測定工程において、上記のように構成された触媒担体２の外径Ｄａが測定され、演算工程にて測定結果の外径Ｄａに所定値ｘを加えた径（Ｄａ＋ｘ）が演算され、その演算結果が、触媒担体２を保持する部分の最適外径Ｄｘとして設定される。この最適外径Ｄｘに基づき、筒状部材４に対し、後述する加工工程によって、触媒担体２の外径Ｄａより大きく軸方向に略均等な内径Ｄｃの円形断面の中空部を有し、触媒担体２の外径Ｄａに所定値２ｄ（ｄは緩衝マット３の最適圧縮時厚さ）を加えた内径Ｄｂ（＝Ｄａ＋２ｄ）の円形断面の中空部を有する保持部４１が形成される。ここで、ｘ＝２ｄ＋２ｅ（ｅは筒状部材４の板厚）であり、最適外径ＤｘはＤｂ＋２ｅ（＝Ｄａ＋２ｄ＋２ｅ）となる。
【００１８】
触媒担体２の外径Ｄａの測定方法としては、直接スケールで測定する方法、専用機やロボットで測定する方法、間接的にカメラ画像等から自動演算する方法等、種々の方法があるが、何れの方法を用いてもよい。測定対象として外径を直接測定することとしてもよいが、直接あるいは間接的に周長や断面積を測定した後に外径を演算することとしてもよい。測定位置による外径のバラツキに対しては、適宜、複数箇所での測定結果の平均値を求め、これを外径の値とし、あるいは最小径又は最大径を外径の値としてもよい。そして、触媒担体２の外径Ｄａの値と緩衝マット３の最適圧縮時厚さｄの２倍を加算した結果（Ｄａ＋２ｄ）が、後述する保持部４１の内径Ｄｂとして設定される。次に、巻回工程において、触媒担体２の外周に緩衝マット３が巻回される（図１には緩衝マット３が巻回された状態を示す）。更に、必要に応じ可燃性テープ（図示せず）等によって固定される。尚、触媒担体２の断面が楕円形断面あるいは長円形断面である場合には、外径の大小は相似形断面における所定位置での外径（例えば長径）が基準とされる。
【００１９】
一方、加工工程において、例えばステンレススティール管が図１の下方に示すように縮径加工されて筒状部材４（尚、加工後は外筒あるいはハウジングと呼ばれる）が形成される。加工対象の管素材としては、ステンレススティール管に限らず、他の金属管を用いることとしてもよく、材質は任意である。また、適宜、前工程にて板材から造管することとしてもよく、既成のパイプ材を切断してもよい。管素材の板厚ｅも任意であるが、触媒コンバータ用としては、１乃至３ｍｍ程度の板厚が望ましい。管素材の必要外径は、当然乍ら、後述する縮径加工（サイジング）後の外径（Ｄｘ等）より大径に設定される。尚、加工工程における縮径加工の具体的方法については、図３乃至図５を参照して後述する。
【００２０】
ここで、縮径加工後の筒状部材４の一例について説明する。管素材（図示せず）の例えば中央部が前述の演算工程で設定された最適外径Ｄｘになるまで縮径加工されて、図１の下方及び図２の左端に示すように保持部４１が形成され、その両側にテーパ部４２，４３並びに非縮径部たる大径部４４，４５が形成され、中間部材として筒状部材４が構成される。後述する圧入工程においてガイド機能を果たす一方側のテーパ部４２については、そのテーパ面が管軸に対し２度乃至１５度の傾斜角度とすることが望ましく、圧入時の最適角度として２度乃至６度に設定される。テーパ部４２は必ずしも平面である必要はなく、ガイド機能を果たし得る限り曲面としてもよい。尚、他方側のテーパ部４３は圧入工程とは無関係であるので、その他の条件に基づいて設定される。
【００２１】
具体的には、保持部４１は、前述のように触媒担体２の外径Ｄａより大きく軸方向に略均等な内径Ｄｃの円形断面の中空部を有し、触媒担体２の外径Ｄａに所定値（２ｄ）を加えた内径Ｄｂの円形断面の中空部が形成されるように、保持部４１の外径はＤｘ（＝Ｄｂ＋２ｅ）に形成される。そして、テーパ部４２，４３から筒状部材４の両開口端に至るまでは、筒状部材４の元の寸法（内径Ｄｃ）が維持され、非縮径部の大径部４４，４５となる。
【００２２】
次に、圧入工程にて、上記のように形成された筒状部材４に対し、図１に示すように緩衝マット３が巻回された触媒担体２が圧入される。図２は圧入工程を示すもので、触媒担体２の一端面が圧入装置５によって押圧され、（Ａ）乃至（Ｄ）の順に、触媒担体２及び緩衝マット３が筒状部材４の保持部４１内に圧入される。このとき、図２の（Ｂ）及び（Ｃ）に示すように、テーパ部４２が圧入時のガイドとして機能し、従来の挿入治具と同様のガイド機能を果たす。尚、圧入工程の作業としては、図２の（Ａ）及び（Ｂ）を手作業とし、作業者の手によって筒状部材４の大径部４３から触媒担体２及び緩衝マット３を挿入し、（Ｂ）のように緩衝マット３がテーパ部４２に接触するように位置決めした状態で、圧入装置５を駆動し（Ｂ）から（Ｃ）に進むように構成した方が、確実かつ効率的である。
【００２３】
而して、緩衝マット３が圧縮されつつ触媒担体２及び緩衝マット３が筒状部材４の保持部４１内に圧入され、図２の（Ｄ）にて圧入作業が完了し、触媒担体２及び緩衝マット３が筒状部材４の保持部４１内に保持される。この（Ｄ）に示す状態で製品として出荷することもできるが、本実施形態では、触媒コンバータの前後に配置する部品に対し、そのまま接続し得るように、筒状部材４の前後を縮径加工してテーパ部及び小径直管部から成るボトルネック部を一体的に形成するものである。尚、筒状部材４にボトルネック部を一体的に形成するネッキング工程については、図６を参照して後述する。
【００２４】
ここで、前述の加工工程における縮径加工の具体例について説明する。先ず、加工対象のワークを縮径加工して筒状部材４を形成する方法として、後述するスピニング加工がある。この場合において、図３及び図４に示すように、ワーク（筒状部材４）を軸回りに回転させてスピニング加工を行なう方法（ワーク回転式）と、図５に示すように、ワーク（筒状部材４）を固定し、その回りにローラを公転させて加工する方法（ワーク固定式）があり、更に、これらを組合せた加工方法としてもよい。
【００２５】
図３において、ワーク（筒状部材４）は主軸６の押板６１とローリングセンタ７の押板７１によって挾持され、主軸６が回転駆動されると、ワーク（筒状部材４）が回転する。押板７１はジョイント７２を介してシリンダ７３に対して回動自在に支持され、シリンダ７３の主軸６方向への押圧力によって押板７１がワーク（筒状部材４）の端面に強く押圧されている。スピニングローラ８は支持部材（図示せず）に回動自在に支持されており、管軸方向（図３の左右方向）及び径方向（図３の上下方向）に駆動制御されるように構成されている。而して、ワーク（筒状部材４）を回転駆動しながらスピニングローラ８をワーク（筒状部材４）の外面に押し当てることによってスピニング加工が行なわれ、図１に示す形状に加工される。この場合において、後述するネッキング工程で用いる、複数のスピニングローラ（本実施形態では３個）を有するワーク固定式のスピニング装置を用いれば、単一の装置で両工程を行なうことができ、経済的であると同時に、複数のスピニングローラを用いたスピニング加工によって、全長に亘って正確且つ均一に、しかも円滑に保持部４１を形成することができる。
【００２６】
図４の装置は、図３の構成と基本的に同じであるが、スピニング加工時のワーク（筒状部材４）の把持をより確実にするために、ワーク（筒状部材４）の両端をコレットチャックでクランプすることとしたものである。即ち、主軸６０にパワーチャック６２が設けられると共に、ローリングセンタ７にチャック７５が設けられ、これらによってワーク（筒状部材４）の両端が強固に把持されるので、加工が困難な管素材にも対応可能となる。また、シリンダ７３に引込み方向（図４の右方向）の力を発生させて、チャック７５を介してワーク（筒状部材４）に引張り方向の力を付与しながらスピニング加工を行なうこととしてもよい。これによれば、加工部分のスプリングバックを一層抑止することができる。
【００２７】
図５の装置は、ワーク（筒状部材４）の一端が、回転しないパワーチャック６３に把持され、他端も回転しないマンドレル９によって押圧され、従って、ワーク（筒状部材４）は回転不能に把持されている。そして、このワーク（筒状部材４）に対し、複数のスピニングローラ１０を公転させつつ外周面に押しつけることによって、スピニング加工を行なうように構成したものである。即ち、図５に示すように、筒状部材４をパワーチャック６０及びマンドレル９によって回転不能且つ軸方向移動不能に固定し、筒状部材４の少なくとも保持部４１を含む範囲に対し、筒状部材４の外周回りを同径の円形軌跡にて公転する複数のスピニングローラ１０を、筒状部材４の外周面に密着させて公転させ、この公転軌跡を縮小しつつ軸方向に駆動してスピニング加工を行なう。尚、マンドレル１０の軸方向移動及びスピニングローラ１０の公転駆動については、特開２００１−２５８２６号公報に記載された装置と同様の装置によって駆動されるように構成されているので、ここでは説明を省略する。
【００２８】
更に、上記の図３乃至図５を参照して説明したスピニング加工時において、保持部４１の内側に押接しその内径を規定するようなマンドレル（図示せず）を配設することとしてもよい。これにより、一層、形状精度が向上する。また、保持部４１の形成に当り、上記の筒状部材４に対する加工と同様の結果が得られるのであれば、スピニング加工に限らず、別の縮径方法を用いることとしてもよい。
【００２９】
図６は、前述の図２に示す圧入工程に続き、筒状部材４の一端部に対しスピニング加工を行い、その開口端に向かって漸次縮径するテーパ部４６、及びこのテーパ部４６から開口端に至るまでの小径直管部４７から成るボトルネック部を形成するネッキング工程を示すものである。このネッキング工程は、筒状部材４の保持部４１をクランプ１２によって回転不能且つ軸方向移動不能に固定し、保持部４１から開口端に至る端部に対し、該端部の外周回りを同径の円形軌跡にて公転する複数のスピニングローラ１０（本実施形態では３個）を、筒状部材４の外周面に密着させて公転させ、この公転軌跡を縮小しつつ軸方向に駆動してスピニング加工を行なうものである。而して、スピニングローラ１０によって図１のテーパ部４２が除去されてボトルネック部が形成される。尚、図６においては、保持部４１とテーパ部４６との間に、内蔵物の係止用に段部４６ｄが形成されているが、この段部４６ｄを設けることなく保持部４１からテーパ部４６に至るまで連続した滑らかな面に形成することもできる。
【００３０】
更に、保持部４１の軸に対し、同軸、傾斜軸及び偏芯軸を適宜組み合わせてネッキング加工を行なうこともできる。尚、これらの偏芯軸及び傾斜軸を含むスピニング加工方法については特開平１１−１４７１３８号公報、特開平１１−１５１５３５号及び特開２００１−２５８２６号公報に開示されており、これらの加工方法を筒状部材４の端部の成形に適用することができる。この場合にも、マンドレル（図示せず）を用い、これを傾斜あるいは偏芯するように配置して、スピニングローラによるネッキング加工を行なうこととしてもよい。
【００３１】
尚、この場合のスピニング加工方法は、前述のワーク回転式（但し、これは同軸加工のみに適用可能）、及びワーク固定式（同軸、偏芯及び傾斜の何れにも適用でき、これらを適宜組み合わせた加工も可能）の何れを採用してもよいが、本実施形態のように筒状部材４内に触媒担体２が収容されている場合には、ワーク固定式が望ましい。
【００３２】
図７は、上記図６に示すように製造された触媒コンバータに対し、更に大径部４５内に、消音器を構成する隔壁９１、インナパイプ９２及びアウトレットパイプ９３が挿入又は圧入されて大径部４５内で固定され、大径部４５の開口端側（図７の右端部）にスピニング加工が行なわれて、ボトルネック部が形成されたものである。そして、小径直管部４７にはインレットパイプ９４が固定される。これによって、マフラ一体型の触媒コンバータを一貫した工程で製造することができる。
【００３３】
図８及び図９は、一方の端部に傾斜軸を有するボトルネック部を形成した触媒コンバータ（柱体がＤＰＦである場合にはＤＰＦ装置）の製造方法を示すもので、先ず、前述の図３乃至図５に示した方法と同様の方法で図８に示す製品が製造される。そして、図９に示すように、筒状部材４の左端部は図６と同様にスピニング加工が行なわれ、その開口端に向かって漸次縮径するテーパ部４６、及びこのテーパ部４６から開口端に至るまでの小径直管部４７から成る、保持部４１と同軸のボトルネック部が形成されている。これに対し、筒状部材４の右端部は傾斜スピニング加工によって、傾斜軸を中心とするテーパ部４８、及びこのテーパ部４８から開口端に至るまでの小径直管部４９から成る、傾斜軸を有するボトルネック部が形成されている。本実施形態では、スピニングローラ１０（図６）によってテーパ部４２，４３が除去され、保持部４１とテーパ部４６及び４８が滑らかな面で連続した形態とされている。
【００３４】
また、図示は省略するが、本発明の他の実施形態として、次のように製造することとしてもよい。先ず、触媒担体２の断面より大きく軸方向に略均等断面の中空部を有する直管の筒状部材（図示せず）に対し、その一方の開口端側に向かって断面を漸次縮小加工して第１のボトルネック部（図示せず）を形成し、この第１のボトルネック部に連続して筒状部材の軸方向の所定範囲の断面を縮小加工し、触媒担体２の断面の外側に所定幅を加えた断面の中空部を有する保持部（図示せず）を形成し、この保持部から筒状部材の一方の開口端に至るまでの第１の端部（図示せず）の断面を漸次縮小加工して第１のボトルネック部を形成すると共に、保持部に連続して筒状部材の他方の開口端側に向かって断面が漸次拡大するテーパ部（図示せず）を形成し、このテーパ部から他方の開口端に至るまで、筒状部材の元の寸法を維持するように形成する。次に、触媒担体２の周囲に緩衝マット３を巻回した後、触媒担体２及び緩衝マット３を筒状部材の他方の開口端からテーパ部でガイドしつつ筒状部材の保持部に圧入して筒状部材内に保持する。そして、筒状部材のテーパ部から他方の開口端に至るまでの第２の端部（図示せず）に対し、この第２の端部の外周回りを同径の円形軌跡にて公転すると共に第２の端部の径方向に移動する複数のスピニングローラを第２の端部の軸に沿って移動させてスピニング加工を行ない、筒状部材の他方の開口端側に向かって断面を漸次縮小加工しテーパ部を除去して第２のボトルネック部を形成する。
【００３５】
そして、上記の保持部と第１のボトルネック部の形成に当たっては、筒状部材の軸方向の所定位置から筒状部材の一方の開口端側に向かって、筒状部材の外周回りを同径の円形軌跡にて公転すると共に筒状部材の径方向に移動する複数（本実施形態では３個）のスピニングローラを筒状部材の軸に沿って移動させてスピニング加工を行ない、筒状部材のテーパ部を形成すると共に保持部を形成し、且つ保持部から一方の開口端に至るまでの第１の端部に対し、第１の端部の外周回りを同径の円形軌跡にて公転すると共に第１の端部の径方向に移動する複数のスピニングローラを端部の軸に沿って移動させてスピニング加工を行なうと共に、保持部に連続してテーパ面が筒状部材の軸に対し２度乃至６度の傾斜角度となるようにテーパ部を形成することとしてもよい。
【００３６】
如上の製造方法は、前述のようにＤＰＦ装置においても同様に適用することができ、その他の柱体を内装する排気処理装置についても同様の方法で製造することができる。即ち、柱体としては、触媒担体やＤＰＦに限らず、各種改質器や加熱・冷却部材、あるいは熱交換部材や熱回収部材等を含み、その種類は問わない。筒状部材に圧入する触媒担体等の柱体は複数でもよく、例えば、保持部の両側にガイド機能を有するテーパ部を形成し、両側から同時に、あるいは順次２個の柱体を圧入することとしてもよい。
【００３７】
また、柱体には、例えば楕円形断面の触媒担体及びＤＰＦも包含される。従って、この場合には、図１を参照して説明すると、筒状部材４が触媒担体２等の楕円形断面より大きく軸方向に略均等の楕円形断面の中空部を有し、筒状部材４の軸方向の所定範囲の断面を縮小加工して、触媒担体２等の楕円形断面の外側に所定幅を加えた楕円形断面の中空部を有する保持部４１が形成されると共に、この保持部４１に連続して一方の開口端側に向かって断面が漸次拡大するテーパ部４２が形成され、このテーパ部４２から前記開口端に至るまで、筒状部材４の元の寸法を維持するように形成され、大径部４４が形成されることになる。尚、この大径部４４の断面は円形でも非円形でもよい。
【００３８】
尚、図２の（Ｄ）に示す状態で製品として出荷した場合には、図１０に示すように、筒状部材４に対し、フランジ９７，９８を介してボトルネック部材９５，９６を接続する構成となる。これによれば、触媒担体２（柱体がＤＰＦである場合にはＤＰＦ）を適宜取り出してメインテナンスを行なうことができるものの、筒状部材４とボトルネック部材９５，９６との間にフランジ９７，９８が存在し、前述の実施形態のような、筒状部材とボトルネック部が一体的に形成され、両者間を滑らかな面とすることができるものではないので、用途が制限される。
【００３９】
【発明の効果】
本発明は上述のように構成されているので以下に記載の効果を奏する。即ち、請求項１に記載の排気処理装置の製造方法においては、柱体及び緩衝部材を筒状部材内に圧入する際テーパ部がガイド機能を果たすので、これらを過剰に圧縮することなく適切且つ容易に圧入することができ、筒状部材内に柱体及び緩衝部材を確実に保持することができる。従って、脆弱な触媒担体も適切に圧入し、確実に保持することができる。しかも、触媒担体を保持した状態で、テーパ部から開口端に至るまでの端部に対し、複数のスピニングローラを用いたスピニング加工によってボトルネック部を容易に形成することができ、テーパ部が除去されて保持部から開口端に向けて滑らかな面で連続するボトルネック部を一体的に形成することができる。特に、所望の形状のボトルネック部を良好な形状精度で形成することができる。
【００４０】
上記の排気処理装置の製造方法において、請求項２に記載のように構成すれば、筒状部材の軸方向の所定範囲を、スピニング加工によって縮径して保持部を形成すると共に、保持部に連続してテーパ面が筒状部材の軸に対し２度乃至６度の傾斜角度となるようにテーパ部を形成することとしているので、全長に亘って正確且つ均一に、しかも円滑に保持部を形成すると共に、圧入に最適なテーパ部を形成することができる。また、ボトルネック部の加工に用いたスピニング装置を用いることとすれば、一層経済的である。
【００４１】
また、請求項３に記載の排気処理装置の製造方法においては、筒状部材に第１のボトルネック部、保持部及びテーパ部を形成した後に、柱体及び緩衝部材を筒状部材内に圧入するように構成されているので、テーパ部がガイド機能を果たし適切且つ容易に圧入することができ、筒状部材内に柱体及び緩衝部材を確実に保持することができると共に、触媒担体を保持した状態で、テーパ部から開口端に至るまでの第２の端部に対し、複数のスピニングローラを用いたスピニング加工によって第２のボトルネック部を容易に形成することができ、テーパ部が除去されて保持部から開口端に向けて滑らかな面で連続する第２のボトルネック部を一体的に形成することができる。
【００４２】
更に、上記の排気処理装置の製造方法において、請求項４に記載のように構成すれば、複数のスピニングローラを用いたスピニング加工によって、第１のボトルネック部を適切且つ容易に形成することができると共に、テーパ部が除去されて保持部から開口端に向けて滑らかな面で連続する第２のボトルネック部を適切且つ容易に形成することができる。しかも、所望の形状のボトルネック部を良好な形状精度で形成することができる。また、第１のボトルネック部の縮径加工に用いたスピニング装置を用いることとすれば、一層経済的である。
【図面の簡単な説明】
【図１】本発明の一実施形態に係る触媒コンバータの製造方法において、緩衝マットを巻回した触媒担体を筒状部材内に圧入する状態を示す斜視図である。
【図２】本発明の一実施形態に係る触媒コンバータの製造方法において、緩衝マットを巻回した触媒担体を筒状部材内に圧入する圧入工程を示す工程図である。
【図３】本発明の一実施形態に係る触媒コンバータの製造方法において、筒状部材に対しスピニング加工によって縮径加工を行う装置のうち、ワーク回転式の一例を示す一部断面図である。
【図４】本発明の一実施形態に係る触媒コンバータの製造方法において、筒状部材に対しスピニング加工によって縮径加工を行う装置のうち、ワーク回転式の他の例を示す一部断面図である。
【図５】本発明の一実施形態に係る触媒コンバータの製造方法において、筒状部材の保持部に対しスピニング加工によって縮径加工を行う装置のうち、ワーク固定式の一例を示す一部断面図である。
【図６】本発明の一実施形態に係る触媒コンバータの製造方法において、筒状部材の端部に対しスピニング加工によって縮径加工を行いボトルネック部を形成する状態を示す一部断面図である。
【図７】本発明の一実施形態に係る触媒コンバータの製造方法において、消音器を構成する部品を内蔵するボトルネック部を形成したマフラ一体型の触媒コンバータを示す一部断面図である。
【図８】本発明の一実施形態に係る触媒コンバータの製造方法において、緩衝マットを巻回した触媒担体を筒状部材内に圧入した状態を示す一部断面図である。
【図９】本発明の一実施形態に係る触媒コンバータの製造方法において、傾斜軸を有するボトルネック部を一方の端部に形成した触媒コンバータを示す一部断面図である。
【図１０】比較例として、筒状部材とボトルネック部材をフランジ接合とした触媒コンバータを示す一部断面図である。
【図１１】従来の触媒コンバータの製造方法において、緩衝マットを巻回した触媒担体を筒状部材内に圧入する圧入工程を示す工程図である。
【図１２】図１１に示した挿入治具の一部を拡大して示す断面図である。
【符号の説明】
２，２０触媒担体，３，３０緩衝マット，
４，４０筒状部材，４１保持部，４２，４３テーパ部，
４４，４５大径部，５圧入装置，６主軸，
７ローリングセンタ，８，１０スピニングローラ，
９マンドレル，１００挿入治具[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of manufacturing an exhaust treatment device that holds a columnar body in a cylindrical member via a buffer member, for example, as a method of manufacturing a catalytic converter that holds a catalyst carrier in a cylindrical member via a buffer mat. According to a preferred manufacturing method.
[0002]
[Prior art]
Recently, a catalytic converter is mounted on an automobile. As a manufacturing method thereof, a ceramic buffer mat is wound around the outer periphery of the catalyst carrier as a buffer member, and the buffer mat is compressed while being compressed in the casing (tubular member). The method of press-fitting into is common.
[0003]
For example, as shown in FIG. 11, a method for manufacturing a catalytic converter for an internal combustion engine includes a method of winding a ceramic buffer mat 30 as a buffer member around the outer periphery of the catalyst carrier 20 and housing these in a cylindrical member 40. Are known. In this case, a method of press-fitting from one opening of the cylindrical member 40 while compressing the buffer mat 30 (press-fitting method) is generally used, and the annular insertion jig 100 is fitted into one opening of the cylindrical member 40. The catalyst carrier 20 and the buffer mat 30 are press-fitted through this. The insertion jig 100 is a rigid body (e.g., made of metal), and in order to facilitate the insertion of the buffer mat 30 and to absorb variations in the diameter of the cylindrical member 40, as shown in an enlarged view in FIG. A structure that protrudes (overhangs) inside the cylindrical member 40 by a distance g is adopted. Accordingly, the inner diameter of the opening of the insertion jig 100 is smaller than the inner diameter of the cylindrical member 40 by 2 g, and when the catalyst carrier 20 and the buffer mat 30 are press-fitted, this protrusion is substantially the minimum diameter. .
[0004]
Therefore, when the catalyst carrier 20 and the buffer mat 30 are press-fitted into the cylindrical member 40, the compression amount of the buffer mat 30 is determined by the insertion jig so as to avoid any damage caused by excessive compression. It must be set to a small value that can pass through 100 protrusions. However, as a result, the compression amount of the buffer mat 3 after the press-fitting is insufficient, and it becomes difficult to reliably hold the catalyst carrier 20.
[0005]
In addition, as a disadvantage of the press-fitting method, the variation in the outer diameter of the catalyst carrier (error) and the variation in the outer diameter of the cylindrical member (error) cannot be absorbed. There is a problem in that the retention of the catalyst carrier in the tank becomes uncertain. In order to solve this, an optimal combination that offsets the variation in the outer diameters of the catalyst carrier and the cylindrical member may be selected, but it is difficult to cope with in the mass production process, and the optimal combination does not always exist.
[0006]
Regarding the method of assembling a press-fitting type catalytic converter using the above-mentioned insertion jig, Japanese Patent Publication No. 60-24286 discloses that a cushion body covering the catalyst carrier is first inserted and cured when inserted into the main body of the catalyst carrier casing. The primary compression in the radial direction is inserted through the insertion hole of the tool and inserted into the large diameter portion of the casing main body, and then the cushion body after the primary compression is secondarily compressed in a radial direction stepwise by the inclined step portion of the casing main body. A method has been proposed for insertion into the central part of the subject. At this time, since the minimum inner diameter of the insertion hole is set smaller than the inner diameter of the large diameter portion of the casing main body, the insertion of the cushion body into the casing main body can be smoothly performed without being obstructed by the end surface of the casing main body. In addition, since the minimum inner diameter of the insertion hole is set larger than the inner diameter of the central portion of the casing main body, the cushion body is not over-compressed in the radial direction depending on the insertion jig.
[0007]
[Problems to be solved by the invention]
However, in the method for assembling the catalytic converter described in the above Japanese Patent Publication No. 60-24286, the end-conical terminal cases 11 and 12 having the outlet 9 or the inlet 10 opened at both opening ends of the casing main body 1 are provided. As it is described that the assembly of the catalytic converter is completed by welding, the terminal case is configured to be welded to both ends of the casing main body, and the casing main body and the terminal case are integrally formed. is not. Therefore, although the problem at the time of inserting the cushion body into the casing main body is solved, the welding process with the terminal case is essential, and the treatment of the joint portion is also necessary. Thus, the catalytic converter described in the above publication is not only a large number of parts, but is not an easy method for manufacturing a catalytic converter.
[0008]
Further, not only the catalytic converter but also a DPF device or the like that holds a diesel particulate filter (DPF) through a buffer member in a cylindrical member, the same problem as described above has become apparent. Thus, there is a demand for an appropriate manufacturing method of a device that holds a fragile columnar body in a cylindrical member via a buffer member.
[0009]
Therefore, the present invention provides a method for manufacturing an exhaust treatment apparatus that holds a columnar body in a cylindrical member via a buffer member, and the column body and the buffer member are easily and appropriately press-fitted and securely held in the cylindrical member. In addition, an object of the present invention is to make it possible to easily and integrally form a bottleneck portion that is continuous with a smooth surface from the holding portion toward the opening end.
[0010]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the present invention provides a method for manufacturing an exhaust treatment apparatus in which a columnar body is held in a cylindrical member via a buffer member, as defined in claim 1, wherein the cylindrical member is the column. A cross section having a hollow portion having a substantially uniform cross section in the axial direction that is larger than the cross section of the body, and by reducing the cross section in a predetermined range in the axial direction of the cylindrical member and adding a predetermined width to the outside of the cross section of the column A holding portion having a hollow portion and a tapered portion whose cross section gradually increases toward at least one opening end side continuously from the holding portion, and extends from the tapered portion to the opening end. The cylindrical member is formed so as to maintain the original dimensions, and the buffer member is wound around the column body, and then the column body and the buffer member are connected to the opening end of the cylindrical member. From While guiding with the taper part The cylindrical member is press-fitted into and held in the cylindrical member, and the end of the cylindrical member extending from the tapered portion to the opening end has the same diameter around the outer periphery. A plurality of spinning rollers that revolve in a circular path and move in the radial direction of the end portion are moved along the axis of the end portion to perform spinning processing, and a cross section of the end portion toward the opening end side. Progressively reduced Remove the taper Thus, the bottleneck portion is formed.
[0011]
In the manufacturing method described above, examples of devices to be manufactured include exhaust treatment devices such as catalytic converters and diesel exhaust treatment devices. The cylindrical member is also called an outer cylinder or a housing. In the case of a catalytic converter, the column body corresponds to a catalyst carrier, and the buffer member corresponds to a buffer mat for the catalyst carrier. In the case of a diesel exhaust treatment device, the column body corresponds to a diesel particulate filter (DPF), and the buffer member corresponds to a buffer mat for DPF. The catalyst carrier and the DPF constituting the column are generally formed in a columnar shape or a cylindrical shape and have a circular cross section, but some have a noncircular cross section such as an ellipse or an ellipse. The column includes those having a non-circular cross section. In addition, although the diameter reduction process of a holding | maintenance part can be performed by spinning as follows, it is good also as using another diameter reduction apparatus.
[0012]
In particular, in the above manufacturing method, as described in claim 2, the cylindrical member revolves around the outer periphery of the cylindrical member in a circular locus having the same diameter and revolves around the cylindrical member. Spinning is performed by moving a plurality of spinning rollers that move in the radial direction of the member along the axis of the cylindrical member, and the holding portion is formed by reducing the diameter of a predetermined range in the axial direction of the cylindrical member. At the same time, the tapered portion is formed so that the tapered surface is continuous with the holding portion at an inclination angle of 2 to 6 degrees with respect to the axis of the cylindrical member. It is good as well. In this case, for example, the spinning process may be performed on the cylindrical member in a state where both ends of the cylindrical member are fixed.
[0013]
Alternatively, according to a third aspect of the present invention, in the method for manufacturing an exhaust treatment apparatus in which the columnar body is held in the cylindrical member via the buffer member, the cylindrical member is substantially larger in the axial direction than the cross-section of the columnar body. A hollow portion having a uniform cross section is formed, a cross section of a predetermined range in the axial direction of the cylindrical member is reduced, and a holding portion having a hollow portion having a cross section obtained by adding a predetermined width to the outside of the cross section of the column body is formed. The first bottleneck portion is formed by gradually reducing the cross section of the first end portion from the holding portion to one open end of the cylindrical member, and the first bottleneck portion is formed continuously with the holding portion. A tapered portion whose cross section gradually expands toward the other opening end side of the tubular member is formed, and the original dimension of the tubular member is maintained from the tapered portion to the other opening end. And after winding the buffer member around the pillar, the pillar and The serial buffer member from the other opening end While guiding with the taper part The second end of the cylindrical member is pressed into the holding portion of the cylindrical member and held in the cylindrical member, and the second end from the tapered portion of the cylindrical member to the other opening end. A plurality of spinning rollers that revolve around a circular locus of the same diameter and move in the radial direction of the end portion along the axis of the second end portion to perform a spinning process. Reduce the cross section gradually toward the other open end of the shaped member. Remove the taper Thus, the second bottleneck portion may be formed.
[0014]
Furthermore, in the above manufacturing method, as described in claim 4, around the outer periphery of the cylindrical member from a predetermined position in the axial direction of the cylindrical member toward one opening end side of the cylindrical member. A plurality of spinning rollers that revolve around a circular locus of the same diameter and move in the radial direction of the cylindrical member are moved along the axis of the cylindrical member to perform spinning, and the tapered portion of the cylindrical member is Forming the holding portion, and revolving around the outer circumference of the first end with a circular locus of the same diameter with respect to the first end portion extending from the holding portion to the one opening end. At the same time, a plurality of spinning rollers that move in the radial direction of the first end portion are moved along the axis of the first end portion to perform spinning, thereby forming the first bottleneck portion. At the same time, the tapered portion is formed so that the tapered surface is continuous with the holding portion at an inclination angle of 2 to 6 degrees with respect to the axis of the cylindrical member. It is good as well.
[0015]
In the above manufacturing method, the outer diameter of the column body may be measured in advance, and a diameter obtained by adding a predetermined value to the measurement result may be an optimum outer diameter, and the holding portion may be formed based on the optimum outer diameter. Good. Thereby, it can carry out continuously in one process including a measurement. Also , In the cylindrical member, in addition to the column body and the buffer member, other components may be accommodated and press-fitted into the cylindrical member.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
In the above method for manufacturing an exhaust treatment apparatus that holds a columnar body through a buffer member, a method for manufacturing a catalytic converter will be described with reference to the drawings. As shown in the upper part of FIG. 1, a buffer mat 3 as a buffer member of the present invention is wound around the outer periphery of the catalyst carrier 2 constituting the column of the present invention, and is fixed with a combustible tape or the like as necessary. In this embodiment, the catalyst carrier 2 is made of ceramics, but may be made of metal. Although the buffer mat 3 is made of an alumina mat that hardly expands due to heat in the present embodiment, a thermal expansion type vermiculite buffer mat may be used. Moreover, you may use the wire mesh etc. which knitted the metal fine wire, and may use it in combination with a ceramic mat. Further, they may be combined with a metal annular retainer.
[0017]
In the manufacturing method of the present embodiment, first, the outer diameter Da of the catalyst carrier 2 configured as described above is measured in the measurement step, and the predetermined value x is added to the outer diameter Da of the measurement result in the calculation step. (Da + x) is calculated, and the calculation result is set as the optimum outer diameter Dx of the portion holding the catalyst carrier 2. Based on the optimum outer diameter Dx, the cylindrical member 4 has a hollow portion with a circular cross section having an inner diameter Dc larger than the outer diameter Da of the catalyst carrier 2 and substantially uniform in the axial direction by a processing step described later. A holding portion 41 having a hollow portion having a circular cross section with an inner diameter Db (= Da + 2d) obtained by adding a predetermined value 2d (d is the optimum compression thickness of the buffer mat 3) to the outer diameter Da of 2 is formed. Here, x = 2d + 2e (e is the plate thickness of the cylindrical member 4), and the optimum outer diameter Dx is Db + 2e (= Da + 2d + 2e).
[0018]
There are various methods for measuring the outer diameter Da of the catalyst carrier 2, such as a method of directly measuring on a scale, a method of measuring with a dedicated machine or a robot, and a method of automatically calculating indirectly from a camera image or the like. The method may be used. Although the outer diameter may be directly measured as a measurement target, the outer diameter may be calculated after measuring the circumference or cross-sectional area directly or indirectly. For the variation in the outer diameter depending on the measurement position, an average value of the measurement results at a plurality of locations may be obtained as appropriate, and this may be used as the outer diameter value, or the minimum or maximum diameter may be used as the outer diameter value. A result (Da + 2d) obtained by adding the value of the outer diameter Da of the catalyst carrier 2 and twice the optimum compression thickness d of the buffer mat 3 is set as the inner diameter Db of the holding portion 41 described later. Next, in the winding step, the buffer mat 3 is wound around the outer periphery of the catalyst carrier 2 (a state where the buffer mat 3 is wound is shown in FIG. 1). Furthermore, it is fixed with a combustible tape (not shown) or the like as required. When the cross section of the catalyst carrier 2 is an elliptical cross section or an oval cross section, the outer diameter is based on the outer diameter (for example, the long diameter) at a predetermined position in the similar cross section.
[0019]
On the other hand, in the processing step, for example, a stainless steel tube is reduced in diameter as shown in the lower part of FIG. 1 to form a cylindrical member 4 (hereinafter referred to as an outer cylinder or a housing). The tube material to be processed is not limited to a stainless steel tube, and other metal tubes may be used, and the material is arbitrary. Moreover, it is good also as making a pipe from a board | plate material in a front process suitably, and may cut an existing pipe material. The thickness e of the tube material is arbitrary, but a thickness of about 1 to 3 mm is desirable for the catalytic converter. Needless to say, the necessary outer diameter of the tube material is set to be larger than the outer diameter (Dx or the like) after diameter reduction processing (sizing) described later. In addition, the specific method of the diameter reduction process in a process process is later mentioned with reference to FIG. 3 thru | or FIG.
[0020]
Here, an example of the cylindrical member 4 after the diameter reduction processing will be described. For example, the central portion of the tube material (not shown) is reduced until the optimum outer diameter Dx set in the above-described calculation step is reached, and the holding portion 41 is formed as shown in the lower part of FIG. 1 and the left end of FIG. The tapered portions 42 and 43 and the large diameter portions 44 and 45 which are non-reduced diameter portions are formed on both sides thereof, and the tubular member 4 is configured as an intermediate member. As for the tapered portion 42 on one side that performs a guide function in a press-fitting process described later, it is desirable that the tapered surface has an inclination angle of 2 degrees to 15 degrees with respect to the tube axis. Set to degrees. The taper portion 42 is not necessarily a flat surface, and may be a curved surface as long as it can perform a guide function. In addition, since the other side taper part 43 is irrelevant to a press-fit process, it sets based on other conditions.
[0021]
Specifically, the holding portion 41 has a hollow portion having a circular cross section with an inner diameter Dc that is larger than the outer diameter Da of the catalyst carrier 2 and is substantially equal in the axial direction as described above, and the outer diameter Da of the catalyst carrier 2 has a predetermined value. The outer diameter of the holding portion 41 is formed to be Dx (= Db + 2e) so that a hollow portion having a circular cross section with an inner diameter Db added with the value (2d) is formed. The original dimension (inner diameter Dc) of the cylindrical member 4 is maintained from the tapered portions 42 and 43 to both open ends of the cylindrical member 4, and the large diameter portions 44 and 45 of the non-reduced diameter portion are obtained. .
[0022]
Next, in the press-fitting step, the catalyst carrier 2 around which the buffer mat 3 is wound is press-fitted into the cylindrical member 4 formed as described above, as shown in FIG. FIG. 2 shows a press-fitting process. One end surface of the catalyst carrier 2 is pressed by the press-fitting device 5, and the catalyst carrier 2 and the buffer mat 3 are held by the holding portion 41 of the cylindrical member 4 in the order of (A) to (D). It is press-fitted inside. At this time, as shown in FIGS. 2B and 2C, the tapered portion 42 functions as a guide at the time of press-fitting, and performs the same guide function as a conventional insertion jig. 2 (A) and 2 (B) are manual operations, and the catalyst carrier 2 and the buffer mat 3 are inserted from the large-diameter portion 43 of the tubular member 4 by the operator's hand. It is more reliable and efficient that the press-fitting device 5 is driven to proceed from (B) to (C) in a state where the buffer mat 3 is positioned so as to contact the tapered portion 42 as shown in (B). is there.
[0023]
Thus, the catalyst carrier 2 and the buffer mat 3 are press-fitted into the holding portion 41 of the cylindrical member 4 while the buffer mat 3 is compressed, and the press-fitting operation is completed in FIG. The buffer mat 3 is held in the holding portion 41 of the cylindrical member 4. Although it can be shipped as a product in the state shown in (D), in this embodiment, the front and rear of the cylindrical member 4 are reduced in diameter so that they can be connected as they are to the parts arranged before and after the catalytic converter. Thus, a bottleneck portion composed of a taper portion and a small diameter straight pipe portion is integrally formed. The necking process for integrally forming the bottleneck portion on the cylindrical member 4 will be described later with reference to FIG.
[0024]
Here, a specific example of diameter reduction processing in the above-described processing step will be described. First, as a method for forming the cylindrical member 4 by reducing the diameter of a workpiece to be processed, there is a spinning process described later. In this case, as shown in FIG. 3 and FIG. 4, a method of spinning the workpiece (cylindrical member 4) around the axis (work rotating type) and a workpiece (cylinder) as shown in FIG. 5. There is a method (work fixing type) in which the shaped member 4) is fixed and the roller is revolved around the fixed member 4), and a processing method in which these are combined may be used.
[0025]
In FIG. 3, the workpiece (cylindrical member 4) is held by a pressing plate 61 of the main shaft 6 and a pressing plate 71 of the rolling center 7, and when the main shaft 6 is driven to rotate, the work (cylindrical member 4) rotates. The pressing plate 71 is rotatably supported with respect to the cylinder 73 via the joint 72, and the pressing plate 71 is strongly pressed against the end surface of the work (tubular member 4) by the pressing force of the cylinder 73 in the direction of the main shaft 6. Yes. The spinning roller 8 is rotatably supported by a support member (not shown), and is configured to be driven and controlled in the tube axis direction (left-right direction in FIG. 3) and the radial direction (up-down direction in FIG. 3). ing. Thus, the spinning process is performed by pressing the spinning roller 8 against the outer surface of the work (tubular member 4) while rotating the work (cylindrical member 4), and the work is processed into the shape shown in FIG. In this case, if a workpiece fixing type spinning device having a plurality of spinning rollers (three in this embodiment) used in the necking step described later is used, both steps can be performed with a single device, which is economical. At the same time, the holding portion 41 can be formed accurately, uniformly, and smoothly over the entire length by spinning using a plurality of spinning rollers.
[0026]
The apparatus in FIG. 4 is basically the same as the configuration in FIG. 3, but in order to more reliably hold the work (tubular member 4) during spinning, both ends of the work (tubular member 4) are attached. It was decided to clamp with a collet chuck. That is, a power chuck 62 is provided on the main shaft 60 and a chuck 75 is provided on the rolling center 7, so that both ends of the work (tubular member 4) are firmly gripped. It becomes possible to respond. Further, a spinning process may be performed while generating a force in the pulling direction (right direction in FIG. 4) on the cylinder 73 and applying a pulling direction force to the work (tubular member 4) via the chuck 75. . According to this, the spring back of the processed part can be further suppressed.
[0027]
In the apparatus of FIG. 5, one end of a work (tubular member 4) is gripped by a non-rotating power chuck 63, and the other end is pressed by a non-rotating mandrel 9, so that the work (tubular member 4) cannot be rotated. It is gripped. Then, a spinning process is performed by pressing a plurality of spinning rollers 10 against the outer peripheral surface while revolving the workpiece (cylindrical member 4). That is, as shown in FIG. 5, the cylindrical member 4 is fixed by the power chuck 60 and the mandrel 9 so that the cylindrical member 4 cannot rotate and cannot move in the axial direction. A plurality of spinning rollers 10 that revolve around the outer periphery of the circle 4 with a circular locus of the same diameter are brought into close contact with the outer peripheral surface of the cylindrical member 4 and revolved, and the revolving locus is reduced and driven in the axial direction to perform spinning processing. To do. The axial movement of the mandrel 10 and the revolution driving of the spinning roller 10 are configured to be driven by the same device as that described in Japanese Patent Laid-Open No. 2001-25826. Omitted.
[0028]
Furthermore, a mandrel (not shown) that presses against the inside of the holding portion 41 and defines the inner diameter thereof may be disposed during the spinning process described with reference to FIGS. 3 to 5 described above. This further improves the shape accuracy. Further, when the holding portion 41 is formed, as long as the same result as the processing for the tubular member 4 is obtained, not only spinning processing but also another diameter reduction method may be used.
[0029]
6, following the press-fitting step shown in FIG. 2 described above, one end portion of the cylindrical member 4 is subjected to spinning processing, and the tapered portion 46 gradually decreases in diameter toward the opening end, and the taper portion 46 opens from the tapered portion 46. The necking process which forms the bottleneck part which consists of the small diameter straight pipe part 47 to an end is shown. In this necking step, the holding portion 41 of the cylindrical member 4 is fixed by the clamp 12 so as not to be rotatable and axially movable, and the end portion extending from the holding portion 41 to the opening end has the same diameter around the outer periphery. A plurality of spinning rollers 10 (three in this embodiment) that revolve along a circular locus are brought into close contact with the outer peripheral surface of the cylindrical member 4 and revolved, and are driven in the axial direction while reducing the revolution locus to perform spinning. Processing is performed. Thus, the taper portion 42 of FIG. 1 is removed by the spinning roller 10 to form a bottleneck portion. In FIG. 6, a step portion is provided between the holding portion 41 and the taper portion 46 for locking the built-in object. 4 6d is formed, but it is also possible to form a continuous smooth surface from the holding part 41 to the taper part 46 without providing the step part 46d.
[0030]
Furthermore, the necking process can be performed by appropriately combining a coaxial axis, an inclined axis, and an eccentric axis with respect to the axis of the holding portion 41. Incidentally, spinning methods including these eccentric shafts and inclined shafts are disclosed in JP-A-11-147138, JP-A-11-151535, and JP-A-2001-25826. It can be applied to the molding of the end of the cylindrical member 4. In this case as well, a mandrel (not shown) may be used, arranged so as to be inclined or eccentric, and necking with a spinning roller may be performed.
[0031]
In this case, the spinning method can be applied to any of the above-described workpiece rotation type (however, this can be applied only to the coaxial machining) and the workpiece fixing type (coaxial, eccentric, and inclined), which are appropriately combined. However, when the catalyst carrier 2 is accommodated in the cylindrical member 4 as in the present embodiment, a work fixing type is desirable.
[0032]
FIG. 7 shows the catalytic converter manufactured as shown in FIG. 6 with a large diameter by inserting or press-fitting a partition wall 91, an inner pipe 92 and an outlet pipe 93 into the large diameter portion 45 into a silencer. The bottle 45 is fixed in the portion 45 and subjected to spinning processing on the opening end side (the right end portion in FIG. 7) of the large diameter portion 45. An inlet pipe 94 is fixed to the small diameter straight pipe portion 47. As a result, a muffler-integrated catalytic converter can be manufactured in a consistent process.
[0033]
8 and 9 show a manufacturing method of a catalytic converter (a DPF device in the case where the column is a DPF) having a bottleneck portion having an inclined axis at one end. The product shown in FIG. 8 is manufactured by a method similar to the method shown in FIGS. As shown in FIG. 9, the left end portion of the cylindrical member 4 is subjected to spinning processing in the same manner as in FIG. 6, and a tapered portion 46 that gradually decreases in diameter toward the opening end, and the tapered portion 46 opens to the opening end. A bottleneck portion that is coaxial with the holding portion 41 and is formed of a small-diameter straight pipe portion 47 that extends to the bottom is formed. On the other hand, the right end portion of the cylindrical member 4 has an inclined axis formed by an inclined spinning process, which includes a tapered portion 48 centering on the inclined axis and a small diameter straight pipe portion 49 extending from the tapered portion 48 to the opening end. The bottleneck part which has is formed. In the present embodiment, the tapered portions 42 and 43 are removed by the spinning roller 10 (FIG. 6), and the holding portion 41 and the tapered portions 46 and 48 are continuous on a smooth surface.
[0034]
Moreover, although illustration is abbreviate | omitted, it is good also as manufacturing as follows as other embodiment of this invention. First, a straight pipe tubular member (not shown) having a hollow portion having a substantially uniform cross section in the axial direction larger than the cross section of the catalyst carrier 2 is gradually reduced in cross section toward one opening end side. A first bottleneck portion (not shown) is formed, and a cross section of a predetermined range in the axial direction of the cylindrical member is reduced to be continuous with the first bottleneck portion, and outside the cross section of the catalyst carrier 2 A holding portion (not shown) having a hollow portion having a cross section with a predetermined width is formed, and a cross section of a first end portion (not shown) from the holding portion to one open end of the cylindrical member The first bottleneck portion is formed by gradually reducing the width of the cylindrical portion, and a tapered portion (not shown) whose cross section is gradually enlarged toward the other opening end side of the cylindrical member is formed continuously with the holding portion. From the taper part to the other opening end, the original dimensions of the cylindrical member are maintained. That. Next, after the buffer mat 3 is wound around the catalyst carrier 2, the catalyst carrier 2 and the buffer mat 3 are removed from the other opening end of the cylindrical member. While guiding with the taper It press-fits into the holding part of the cylindrical member and holds it in the cylindrical member. And with respect to the 2nd end part (not shown) from the taper part of a cylindrical member to the other opening end, it revolves around the outer periphery of this 2nd end part by the circular locus of the same diameter. Spinning by moving a plurality of spinning rollers moving in the radial direction of the second end portion along the axis of the second end portion, and gradually reducing the cross section toward the other opening end side of the cylindrical member Processed Remove the taper To form a second bottleneck portion.
[0035]
In forming the holding portion and the first bottleneck portion, the same diameter is provided around the outer periphery of the cylindrical member from a predetermined position in the axial direction of the cylindrical member toward one opening end side of the cylindrical member. A plurality of (three in this embodiment) spinning rollers that revolve around the circular locus and move in the radial direction of the cylindrical member are moved along the axis of the cylindrical member to perform the spinning process. A tapered portion and a holding portion are formed, and the first end from the holding portion to one opening end is revolved around the outer periphery of the first end along a circular locus having the same diameter. In addition, a plurality of spinning rollers that move in the radial direction of the first end portion are moved along the axis of the end portion to perform spinning processing. At the same time, the taper portion is formed so that the taper surface has an inclination angle of 2 degrees to 6 degrees with respect to the axis of the cylindrical member continuously from the holding portion. It is good as well.
[0036]
The above manufacturing method can be similarly applied to the DPF device as described above, and the exhaust processing device including other pillars can be manufactured in the same manner. That is, the column body is not limited to the catalyst carrier and the DPF, and includes various reformers, heating / cooling members, heat exchange members, heat recovery members, and the like, and the type thereof is not limited. There may be a plurality of pillars such as a catalyst carrier that are press-fitted into the cylindrical member. For example, a tapered part having a guide function is formed on both sides of the holding part, and two pillars are press-fitted simultaneously or sequentially from both sides. Also good.
[0037]
The column body also includes, for example, a catalyst carrier and a DPF having an elliptical cross section. Therefore, in this case, referring to FIG. 1, the cylindrical member 4 has a hollow portion having an elliptical cross section that is larger than the elliptical cross section of the catalyst carrier 2 and the like and is substantially equal in the axial direction. A holding portion 41 having a hollow portion having an elliptical cross section obtained by adding a predetermined width to the outside of the elliptical cross section of the catalyst carrier 2 or the like is formed by reducing the cross section of a predetermined range in the axial direction of the four, and this holding A tapered portion 42 is formed continuously from the portion 41 toward the one opening end, and the cross section gradually expands. The original dimension of the tubular member 4 is maintained from the tapered portion 42 to the opening end. The large-diameter portion 44 is formed. The cross section of the large diameter portion 44 may be circular or non-circular.
[0038]
When the product is shipped in the state shown in FIG. 2D, the bottleneck members 95 and 96 are connected to the tubular member 4 via the flanges 97 and 98 as shown in FIG. It becomes composition. According to this, although the catalyst carrier 2 (DPF when the column body is DPF) can be taken out and maintenance can be performed appropriately, the flange 97, between the tubular member 4 and the bottleneck members 95, 96 can be performed. 98, and the cylindrical member and the bottleneck portion are integrally formed as in the above-described embodiment, and the use thereof is limited because the surface cannot be made smooth.
[0039]
【The invention's effect】
Since this invention is comprised as mentioned above, there exists an effect as described below. That is, in the method for manufacturing an exhaust treatment device according to claim 1, since the tapered portion performs a guide function when the column body and the buffer member are press-fitted into the cylindrical member, the taper portion appropriately and without excessive compression. It can be easily press-fitted, and the column body and the buffer member can be reliably held in the cylindrical member. Therefore, a fragile catalyst carrier can be appropriately press-fitted and securely held. Moreover, the bottleneck portion can be easily formed by spinning using a plurality of spinning rollers for the end from the taper to the open end while holding the catalyst carrier. The taper is removed A bottleneck portion that is continuous with a smooth surface from the holding portion toward the opening end can be integrally formed. In particular, a bottleneck portion having a desired shape can be formed with good shape accuracy.
[0040]
In the above exhaust processing apparatus manufacturing method, if configured as in claim 2, the holding portion is formed by reducing the diameter of a predetermined range in the axial direction of the cylindrical member by spinning. At the same time, the taper portion is formed so that the taper surface has an inclination angle of 2 degrees to 6 degrees with respect to the axis of the cylindrical member continuously from the holding portion. Therefore, the holding part is formed accurately, uniformly and smoothly over the entire length. Together with it, it forms a taper part that is optimal for press-fitting be able to. In addition, it is more economical if the spinning device used for processing the bottleneck portion is used.
[0041]
In the method for manufacturing an exhaust treatment device according to claim 3, after the first bottleneck portion, the holding portion, and the taper portion are formed in the cylindrical member, the column body and the buffer member are press-fitted into the cylindrical member. Therefore, the tapered portion performs a guide function and can be press-fitted appropriately and easily, and the column body and the buffer member can be securely held in the cylindrical member, and the catalyst carrier is held. In this state, the second bottleneck part can be easily formed by spinning using a plurality of spinning rollers for the second end part from the taper part to the opening end, The taper is removed The second bottleneck portion that is continuous on the smooth surface from the holding portion toward the opening end can be integrally formed.
[0042]
Further, in the above method for manufacturing an exhaust treatment device, if configured as in claim 4, , By spinning using multiple spinning rollers, The first bottleneck part can be formed appropriately and easily, and the taper part is removed. A second continuous surface from the holding part toward the open end with a smooth surface. 2 The bottleneck portion can be appropriately and easily formed. In addition, a bottleneck portion having a desired shape can be formed with good shape accuracy. The second 1 It is more economical if the spinning device used for the diameter reduction processing of the bottleneck portion is used.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a state where a catalyst carrier around which a buffer mat is wound is press-fitted into a cylindrical member in a method for producing a catalytic converter according to an embodiment of the present invention.
FIG. 2 is a process diagram showing a press-fitting process of press-fitting a catalyst carrier wound with a buffer mat into a cylindrical member in the method for manufacturing a catalytic converter according to an embodiment of the present invention.
FIG. 3 is a partial cross-sectional view showing an example of a work rotation type in an apparatus that performs diameter reduction processing by spinning on a cylindrical member in a method for manufacturing a catalytic converter according to an embodiment of the present invention.
FIG. 4 is a partial cross-sectional view showing another example of a workpiece rotation type in an apparatus for reducing the diameter of a cylindrical member by spinning processing in a method for manufacturing a catalytic converter according to an embodiment of the present invention. is there.
FIG. 5 is a partial cross-sectional view showing an example of a workpiece fixing type in an apparatus for performing diameter reduction processing by spinning on a holding portion of a cylindrical member in a method for manufacturing a catalytic converter according to an embodiment of the present invention. It is.
FIG. 6 is a partial cross-sectional view showing a state in which the bottleneck portion is formed by reducing the diameter of the end portion of the cylindrical member by spinning processing in the method for manufacturing the catalytic converter according to the embodiment of the present invention. .
FIG. 7 is a partial cross-sectional view showing a muffler-integrated catalytic converter in which a bottleneck portion containing a component constituting a silencer is formed in a method for manufacturing a catalytic converter according to an embodiment of the present invention.
FIG. 8 is a partial cross-sectional view showing a state in which a catalyst carrier around which a buffer mat is wound is press-fitted into a cylindrical member in a method for manufacturing a catalytic converter according to an embodiment of the present invention.
FIG. 9 is a partial cross-sectional view showing a catalytic converter in which a bottleneck portion having an inclined axis is formed at one end in a method for manufacturing a catalytic converter according to an embodiment of the present invention.
FIG. 10 is a partial cross-sectional view showing a catalytic converter in which a tubular member and a bottleneck member are joined by flange as a comparative example.
FIG. 11 is a process diagram showing a press-fitting process for press-fitting a catalyst carrier wound with a buffer mat into a cylindrical member in a conventional catalytic converter manufacturing method.
12 is an enlarged cross-sectional view of a part of the insertion jig shown in FIG.
[Explanation of symbols]
2,20 catalyst carrier, 3,30 buffer mat,
4, 40 cylindrical member, 41 holding part, 42, 43 taper part,
44, 45 large diameter part, 5 press-fitting device, 6 spindle,
7 Rolling center, 8, 10 Spinning roller,
9 Mandrel, 100 Insertion jig

Claims

In the method of manufacturing an exhaust treatment apparatus that holds a columnar body through a buffer member in the cylindrical member, the cylindrical member has a hollow portion that is larger than a cross section of the columnar body and has a substantially uniform cross section in the axial direction, and the cylinder A cross section of a predetermined range in the axial direction of the cylindrical member is reduced to form a holding portion having a hollow portion with a predetermined width added to the outside of the cross section of the column body, and the holding portion has a small number continuously. In addition, a tapered portion whose cross section gradually increases toward one opening end side is formed so as to maintain the original dimension of the cylindrical member from the tapered portion to the opening end, and After the buffer member is wound around the column body, the column body and the buffer member are pressed into the holding portion of the cylindrical member while being guided by the tapered portion from the opening end of the cylindrical member, and Hold in the cylindrical member, from the tapered portion of the cylindrical member to the opening end A plurality of spinning rollers that revolve around a circular locus of the same diameter and move in the radial direction of the end portion along the axis of the end portion. A method of manufacturing an exhaust treatment apparatus, comprising: performing a spinning process, gradually reducing a cross section of the end portion toward the opening end side, and removing the tapered portion to form a bottleneck portion.

A predetermined range in the axial direction of the cylindrical member revolves around the outer periphery of the cylindrical member along a circular locus of the same diameter, and a plurality of spinning rollers that move in the radial direction of the cylindrical member are provided on the cylindrical member. Spinning is performed by moving along the axis, the holding portion is formed by reducing the diameter of a predetermined range in the axial direction of the cylindrical member, and the tapered surface is continuous with the holding portion. 2. The method of manufacturing an exhaust treatment apparatus according to claim 1 , wherein the tapered portion is formed so as to have an inclination angle of 2 degrees to 6 degrees with respect to an axis .

In the method of manufacturing an exhaust treatment apparatus that holds a columnar body through a buffer member in the cylindrical member, the cylindrical member has a hollow portion that is larger than a cross section of the columnar body and has a substantially uniform cross section in the axial direction, and the cylinder A cross-section of a predetermined range in the axial direction of the cylindrical member is reduced to form a holding portion having a hollow portion having a cross-section with a predetermined width outside the cross-section of the column body, and one of the cylindrical members is formed from the holding portion. The first bottleneck portion is formed by gradually reducing the cross section of the first end portion up to the opening end of the cylindrical member, and continues to the holding portion toward the other opening end side of the cylindrical member. Forming a tapered portion whose cross section gradually increases, and maintaining the original dimension of the cylindrical member from the tapered portion to the other opening end, and surrounding the column body after turning the cushioning member winding, the cylindrical body and the cushioning member from the other opening end Serial and pressed into the holding portion of the tubular member while guided by the tapered portion and held in the tubular member, the second end of the tapered portion of the tubular member until the other opening end On the other hand, a plurality of spinning rollers that revolve around the outer circumference of the second end portion in a circular locus of the same diameter and move in the radial direction of the end portion are moved along the axis of the second end portion. Manufacturing of an exhaust treatment apparatus characterized by performing a spinning process, gradually reducing the cross section toward the other opening end side of the cylindrical member, and removing the tapered part to form a second bottleneck part. Method.

The cylindrical member revolves around the outer periphery of the cylindrical member along a circular locus of the same diameter from a predetermined position in the axial direction of the cylindrical member toward one opening end side of the cylindrical member, and the radial direction of the cylindrical member A plurality of spinning rollers that move to the cylindrical member are moved along the axis of the cylindrical member to perform the spinning process, thereby forming the tapered portion of the cylindrical member and the holding portion, and from the holding portion to the one side A plurality of spinnings that revolve around a circular locus of the same diameter around the outer periphery of the first end up to the open end of the first end and move in the radial direction of the first end Spinning by moving the roller along the axis of the first end, forming the first bottleneck portion, and a tapered surface continuous with the holding portion on the axis of the cylindrical member The inclination angle is 2 to 6 degrees. Method of manufacturing an exhaust processing device according to claim 3, characterized in that to form the over path portion.