JP4294281B2

JP4294281B2 - 2 piece wheel manufacturing method

Info

Publication number: JP4294281B2
Application number: JP2002231712A
Authority: JP
Inventors: 正樹熊谷; 直田中
Original assignee: Sumitomo Light Metal Industries Ltd
Current assignee: Sumitomo Light Metal Industries Ltd
Priority date: 2002-08-08
Filing date: 2002-08-08
Publication date: 2009-07-08
Anticipated expiration: 2022-08-08
Also published as: JP2004066325A

Description

【０００１】
【技術分野】
本発明は、２ピースホイールの製造方法に係り、特に、アルミニウム合金製のリムとディスクとを一体的に接合してなる２ピースホイールの有利な製造方法に関するものである。
【０００２】
【背景技術】
よく知られているように、近年では、自動車等の車両用ホイールとして、軽量性やデザイン性に優れたアルミニウム合金からなるホイールが多用されてきている。そして、そのようなホイールの一種として、アルミニウム合金製のリムを有し、このリムに対して、一方の面が意匠面とされた、アルミニウム合金製のディスクを嵌め込んで、一体的に接合してなる、所謂２ピースホイールが、知られている。
【０００３】
ところで、このアルミニウム合金製の２ピースホイールは、例えば、特開２００１−８８５０４号公報等において明らかにされているように、一般に、全体として略円筒形状を呈するリムの内孔内に、ディスクが、その外周面の一部において、リムの内周面に突き合わされるか若しくは重ね合わされるようにして、嵌め込まれた状態下で、それらリムとディスクとが、アーク溶接等の溶融溶接操作により、突き合わせ部において突合せ接合されるか、或いは重ね合わせ部分に形成される隅肉部において隅肉接合される等して、一体的に接合されて、製造されているのであるが、そのように、リムとディスクとを溶融溶接操作にて接合する場合、溶接時の多大な入熱によって、接合部の強度低下や歪みが発生するといった問題が生ずることが、避けられなかったのである。
【０００４】
一方、特表２０００−５０９３４２号公報には、リムとディスクとを、溶融溶接操作に代えて、摩擦撹拌接合操作により、一体的に接合するようにした２ピースホイールの製造手法が、開示されている。ここで、リムとディスクとの接合に採用される摩擦撹拌接合操作は、よく知られているように、接合されるべき部分を何等溶融せしめることなく固相状態のままで接合するものであるため、接合時の入熱を効果的に少なく為すことが出来のである。従って、かかる公報に開示される２ピースホイールの製造手法によれば、リムとディスクとを溶融溶接操作によって接合した場合に生ずる、接合部の強度低下や歪みの発生等の問題が、有利に解消され得ることとなるのである。
【０００５】
ところが、前記公報に開示される、リムとディスクとを摩擦撹拌接合するようにした従来の２ピースホイールの製造手法にあっては、リムとディスクとを溶融溶接する２ピースホイールの製造手法と同様に、ディスクが、その外周面の一部において、リムの内周面に突き合わされるか、若しくは重ね合わされるようにして、嵌め込まれた状態下で、それらリムとディスクとが、突き合わせ部において突合せ接合されるか、或いは重ね合わせ部分に形成される隅肉部において隅肉接合されているために、リムとディスクとの接合部において、入熱の影響による接合強度の低下は免れるものの、その接合強度が、充分に満足し得るものであるとは、言い難いものであったのである。
【０００６】
また、そのような従来手法では、ロッド状の回転治具の先端に同心的に設けられたピンを、回転治具と共に高速回転せしめつつ、リムとディスクとの突き合わせ面間や重ね合わせ面間に差し込んで、それらリムやディスクに対して相対移動せしめることによって、摩擦撹拌接合操作が行なわれるのであるが、その際に、リムとディスクとのそれぞれの接合されるべき部分の変形を防ぐために、リムとディスクとを、ピンから作用せしめられる押圧力に対抗するように、かかる押圧力が作用せしめられる方向とは反対方向から保持するだけでなく、リムとディスクの位置ずれ防止を図る上で、それらの突き合わせ面や重ね合わせ面が互いに離間しないようにするために、更に別の方向からも保持しなければならず、それが、摩擦撹拌接合操作を煩雑なものと為していたのであり、更に、リムとディスクとの重ね合わせ部分の隅肉部に対する隅肉接合を行なう場合に、かかる隅肉部がリムの意匠面側に形成されていると、接合部の表面が、外部から視認されるリムの意匠面に形成され、それによって、リムの意匠面の意匠性が損なわれて、目的とする２ピースホイールの品質が著しく低下するといった重大な問題が惹起されることとなるのである。
【０００７】
【解決課題】
ここにおいて、本発明は、上述せる如き事情を背景にして為されたものであって、その解決課題とするところは、リムとディスクとを、より簡単な摩擦撹拌接合操作によって、リムの意匠面の意匠性を損なうことなく、より充分な接合強度をもって容易に接合することが出来、以て優れた品質と強度を有するピースホイールを有利に製造する手法を提供することにある。
【０００８】
【解決手段】
そして、本発明にあっては、かかる課題の解決のために、アルミニウム合金材料からなるリムに対して、一方の面が意匠面とされたアルミニウム合金製のディスクを嵌め合わせ、一体的に接合せしめてなる２ピースホイールを製造するに際して、前記ディスクとして、外周縁部に、前記意匠面とは反対側において該意匠面から離れる方向に向かって延びる円筒状フランジ部が設けられてなるものを用いる一方、前記リムとして、内周面が、該ディスクの円筒状フランジ部の外周面に対して重ね合わされる重合面とされた円筒状接合部を有するものを用い、それら円筒状フランジ部の外周面と円筒状接合部の重合面とが互いに重ね合わされるように、該ディスクを該リムに嵌め合わせた後、該ディスクの円筒状フランジ部と該リムの円筒状接合部との重ね合わせ部分における、該ディスクの前記意匠面側の部位に対して、ロッド状の回転治具の先端に同心的に設けたピンを、該回転治具と共に一体回転させつつ、該リムの円筒状接合部の外周面側から、該ディスクの円筒状フランジ部に達するように差し込み、周方向に相対的に移動させることにより、かかる重ね合わせ部分の前記ディスクの意匠面側の部位を摩擦撹拌接合すると共に、前記ディスクの円筒状フランジ部と前記リムの円筒状接合部との重ね合わせ部分における、前記ディスクの意匠面側の部位とはディスク軸方向において反対側となる部位に対して、所定の接合操作を実施し、前記リムと該ディスクとを、かかる重ね合わせ部分の軸方向両端部側部位において、それぞれ、一体的に接合せしめたことを特徴とする２ピースホイールの製造方法を、その要旨とするものである。
【０００９】
要するに、この本発明に従う２ピースホイールの製造方法にあっては、ディスクに設けられた円筒状フランジ部とリムに設けられた円筒状接合部とを互いに重ね合わせた状態下において、それら円筒状フランジ部と円筒状接合部との重ね合わせ部分における、リムの意匠面側となる部位に対して、回転治具と共に一体回転せしめられるピンを、円筒状接合部の外周面側から円筒状フランジ部に達するように差し込み、周方向に相対的に移動させることにより、かかる重ね合わせ部分におけるリムの意匠面側の部位を摩擦撹拌接合するようにしたものである。
【００１０】
それ故、このような本発明に係る２ピースホイールの製造方法においては、摩擦撹拌接合によって形成されるリムとディスクとの接合部が、溶融溶接によって形成される場合とは異なって、多大な入熱による悪影響を受けることが有利に回避され得るばかりでなく、突き合わせ部や隅肉部に対する突き合わせ接合や隅肉接合よりも優れた接合強度が得られる、重ね合わせ部分に対する重ね合わせ接合にて形成されることとなり、それによって、かかる接合部において、より優れた接合強度が、極めて充分に確保され得るのである。
【００１１】
また、かかる本発明に従う２ピースホイールの製造方法では、摩擦撹拌接合操作が、回転治具と共に一体回転せしめられるピンを、円筒状接合部の外周面側から、それに重ね合わされる円筒状フランジ部に達するように差し込み、周方向に相対的に移動させることにより実施されているところから、そのような摩擦撹拌接合操作にて形成される接合部の表面が、タイヤ等が嵌め込まれるリムの外周面に形成されることとなり、それによって、リムとディスクとがリムの意匠面側たる軸方向一方側の端部において接合されているにも拘わらず、リムの意匠面に、接合部の表面が露呈せしめられるようなことが、効果的に回避され得ることとなるのである。
【００１２】
しかも、そのような本発明手法では、上述の如く、回転治具と共に一体回転せしめられるピンが、円筒状接合部と円筒状フランジ部との重ね合わせ部分に対して、円筒状接合部の外周面から円筒状フランジ部に達するように差し込まれて、摩擦撹拌接合操作が行なわれるようになっているため、摩擦撹拌接合操作の実施時において、例えば、それらリムとディスクとを、単に、ピンから作用せしめられる押圧力に対抗するように、かかる押圧力の作用方向とは反対の方向から保持するだけで、かかる押圧力によるリムとディスクとの重ね合わせ部分の変形が防止され得ると共に、リムとディスクとが、それらを保持する所定の保持部材とピンとの間で挟持される状態となって、リムとディスクとの位置ずれが効果的に阻止され得るのであり、それによって、例えば、リムとディスクとを、ピンによる押圧方向とは反対方向以外の方向からも保持しなければならない突き合わせ接合や隅肉接合を行なう場合よりも、摩擦撹拌接合操作の実施時におけるリムとディスクの保持操作、ひいては摩擦撹拌接合操作が、有利に簡素化され得ることとなるのである。
【００１３】
従って、かくの如き本発明に従う２ピースホイールの製造方法によれば、リムの意匠面の意匠性を何等損なうことなく、リムとディスクとを、より簡単な摩擦撹拌接合操作にて、更に一層信頼性の高い接合強度をもって容易に接合することが出来、以て優れた品質と充分な強度とを有する高品質のピースホイールを極めて有利に製造することが可能となるのである。
【００１４】
加えて、このような本発明に従う２ピースホイールの製造方法によれば、前記ディスクの円筒状フランジ部と前記リムの円筒状接合部の重ね合わせ部分における、前記ディスクの意匠面側の部位とは軸方向において反対側となる部位に対して、所定の接合操作が実施されて、前記リムと該ディスクとが、かかる重ね合わせ部分の軸方向両端部側部位において、それぞれ一体的に接合せしめられることとなるが、これによって、リムとディスクとの重ね合わせ部分における軸方向の二箇所に接合部が形成されることとなり、以て、リムとディスクとの接合強度が、更に一層効果的に高められ得るのである。
【００１５】
また、本発明に従う２ピースホイールの製造方法の有利な別の態様の一つによれば、前記ディスクの円筒状フランジ部と前記リムの円筒状接合部との重ね合わせ部分における、前記ディスクの意匠面側の部位とは軸方向において反対側となる部位に対して、ロッド状の回転治具の先端に同心的に設けたピンを、該回転治具と共に一体回転させつつ、該リムの円筒状接合部の外周面側から、該ディスクの円筒状フランジ部に達するように差し込み、周方向に相対的に移動させることにより、かかる重ね合わせ部分の前記意匠面側とは反対側の部位が摩擦撹拌接合される手法が採用される。
【００１６】
かかる構成を採用すれば、リムとディスクの重ね合わせ部における、リムの意匠面側とは反対側の部位に形成される接合部が、リムの意匠面側の部位に形成される接合部と同様に、簡単な摩擦撹拌接合操作による重ね合わせ接合により、優れた接合強度をもって、より容易に形成され得るのであり、それによって、リムとディスクとが、より強固に接合され得て、更に一層、高い品質を有する２ピースホイールが、有利に製造され得ることとなるのである。
【００１７】
さらに、本発明に従う２ピースホイールの製造方法の更に別の望ましい態様の一つによれば、前記ディスクの円筒状フランジ部とリムの円筒状接合部との重ね合わせ部分における、前記ディスクの意匠面側の部位とは軸方向において反対側となる部位の重ね合わせ面間に、ロッド状の回転治具の先端に同心的に設けたピンを、該回転治具と共に一体回転させつつ、該ディスクの前記意匠面側とは反対側から差し込み、周方向に相対的に移動させることにより、かかる重ね合わせ部分の前記意匠面側とは反対側の部位が摩擦撹拌接合されることとなる。これによって、リムとディスクの重ね合わせ部における軸方向両端部にそれぞれ形成される接合部の表面が、リムの外周面と、ホイールの自動車等への装着状態下で、外部から視認不能な、リムの意匠面とは反対側の面とに形成されることとなり、以て、リム、ひいては２ピースホイール全体における優れた意匠性が、より有利に確保され得るのである。
【００１８】
なお、そのように、本発明に従う２ピースホイールの製造方法において、回転治具に設けたピンを、回転下で、ディスクの円筒状フランジ部とリムの円筒状接合部との重ね合わせ部分における重ね合わせ面間に、ディスクの意匠面側とは反対側から差し込んで、重ね合わせ部分におけるリムの意匠面側とは反対側の部位を摩擦撹拌接合する際には、有利には、前記ディスクにおける円筒状フランジ部の外周面と、前記リムにおける円筒状接合部の重合面のうちの少なくとも何れか一方に、径方向に突出する突起が設けられる一方、それらのうちの少なくとも何れか他方に、該突起に対して係合することにより、該リムの意匠面側への該ディスクの該リムに対する相対移動を阻止せしめる係合凹部が設けられる。
【００１９】
このような構成を有する２ピースホイールの製造方法においては、円筒状フランジ部と円筒状接合部のうちの少なくとも何れか一方に設けられた突起を、それらのうちの少なくとも何れか他方に設けられた係合凹部に係合せしめた状態で、ディスクとリムとを、円筒状フランジ部と円筒状接合部とにおいて重ね合わせつつ、嵌め合わせることによって、それらディスクとリムとの嵌合せ状態下での位置決めが容易に行なわれ得るばかりでなく、回転治具のピンを回転させつつ、ディスクの意匠面側とは反対側から差し込み、相対的に移動させることにより、円筒状フランジ部と円筒状接合部の重ね合わせ部分における、リムの意匠面側とは反対側の部位を摩擦撹拌接合する際に、ディスクのリムに対するリムの意匠面側への相対移動が有利に阻止され得、以て、ディスクとリムが、常に一定の位置で接合された２ピースホイールが有利に製造され得ることとなるのである。
【００２０】
また、本発明に従う２ピースホイールの製造方法の他の好ましい態様の一つによれば、前記ディスクの円筒状フランジ部の先端部に、先端に向かうに従って次第に大径化するテーパ状内周面が形成されており、かかるディスクの円筒状フランジ部と前記リムの円筒状接合部とを重ね合わせた状態において、該円筒状フランジ部の前記テーパ状内周面に対して、ロッド状回転治具の先端に同心的に設けたピンを、該回転治具と共に一体回転させつつ、該テーパ状内周面から前記円筒状接合部に達するように、斜めに差し込み、周方向に相対的に移動させることにより、該ディスクの円筒状フランジ部と該リムの円筒状接合部との重ね合わせ部分における、前記ディスクの意匠面側の部位とは軸方向において反対側となる部位が摩擦撹拌接合されることとなる。
【００２１】
このような本発明に従う２ピースホイールの製造方法にあっては、円筒状フランジ部と円筒状接合部の重ね合わせ部分における、リムの意匠面側の部位と同様に、それとは軸方向に反対側の部位も、リムとディスクの保持操作が比較的に簡単な摩擦撹拌接合操作にて重ね合わせ接合せしめられることとなり、それによって、かかる重ね合わせ部分におけるリムの意匠面側とは反対側の部位に対しても、優れた接合強度を有する接合部が容易に形成され得、以て、リムとディスクとが、より強固に且つ容易に接合され得て、更に高品質の２ピースホイールが有利に製造され得ることとなるのである。
【００２２】
なお、そのように、本発明に従う２ピースホイールの製造方法において、円筒状フランジ部の先端部に、先端に向かうに従って次第に大径化するテーパ状内周面が形成されたディスクを用いる場合には、有利には、かかる円筒状フランジ部の先端部におけるテーパ状内周面が、６０〜１２０°の範囲内のテーパ角度を有して、構成される。このような構成を採用すれば、回転治具のピンが、円筒状フランジ部の先端部におけるテーパ状内周面に対して確実に差し込まれ得て、円筒状フランジ部と円筒状接合部の重ね合わせ部分における、リムの意匠面側とは反対側の部位が、より有利に且つ確実に重ね合わせ接合せしめられ得るのであり、その結果として、リムとディスクとが優れた接合強度をもって一体的に接合されてなる２ピースホイールが、安定的に製造され得ることとなるのである。
【００２３】
【発明の実施の形態】
ところで、かくの如き本発明に従う２ピースホイールの製造方法により、例えば、自動車用の２ピースホイールを製造するに際しては、先ず、図１及び図２に示される如きリム１０とディスク１２とが準備されることとなる。
【００２４】
すなわち、ここで準備されるリム１０は、図１に示されるように、所定のアルミニウム合金材料からなり、全体として、軸方向の中間部側よりも両端部側が大径化された略段付円筒形状を有している。そして、ここでは、特に、軸方向の両端部に比して小径とされた軸方向中間部分が、軸方向に真っ直ぐに延びる同一径の筒壁部を備えた円筒状接合部１４とされており、また、この円筒状接合部１４の内周面が、後述するディスク１２の円筒状フランジ部（２０）に重ね合わされる重合面１６として、構成されている（図３参照）。
【００２５】
なお、このような形状のリム１０を製造するには、従来より公知の手法が、適宜に採用される。つまり、例えば、アルミニウム合金よりなる板材をロールフォーミング等により円筒形状に曲げ加工した状態下で、その周方向において突き合わされる突き合わせ部を、フラッシュバット溶接や摩擦撹拌接合等により、一体的に接合して、管体と為し、更に、この管体に対してスピニング加工やロール加工等のプレス成形加工を施して、全体として段付円筒形状を呈する所望の形状に成形することにより、リム１０を得る手法や、アルミニウム合金材料を用いた押出成形操作により、アルミニウム合金製の円筒体を成形し、これを所望の段付円筒形状に成形して、リム１０を得る手法、更には、アルミニウム合金からなる板材を絞り加工することにより、有底の円筒体を成形し、そして、この有底円筒体の底部を除去して、軸方向両側において開口する円筒体を得、更に、かかる円筒体を所望の段付円筒形状に成形することにより、リム１０を得る手法等が、適宜に採用され得るのである。また、かかるリム１０を与えるアルミニウム合金の材質も、何等限定されるものではなく、目的とする２ピースホイールの要求品質等に応じて、適宜に決定されることとなる。
【００２６】
一方、リム１０と共に準備されるディスク１２は、図２に示されるように、所定のアルミニウム合金製で、全体として、リム１０に内嵌可能な大きさの略厚肉円板形状を呈しており、一方の面が、所定のデザインが付与された意匠面１８とされている。また、このディスク１２にあっては、その外周縁部に、意匠面１８とは反対側において意匠面１８から離隔する方向に向かって延びる同一径の円筒状フランジ部２０が一体的に形成されている。つまり、かかるディスク１２は、全体として略有底の円筒形状を有しており、その底部の外面が、意匠面１８とされていると共に、その筒壁部が、円筒状フランジ部２０とされているのである。そして、このディスク１２が、リム１０に対して内嵌せしめられた状態下で、円筒状フランジ部２０の外周面において、リム１０の前記円筒状接合部１４の重合面１６に重ね合わされて、位置せしめられるようになっているのである（図３参照）。
【００２７】
なお、このようなディスク１２の製造手法も、特に限定されるものではなく、アルミニウム合金材を鋳造や鍛造によって、所定の円板形状に成形する手法等が、適宜に採用され得るのである。また、このディスク１２を与えるアルミニウム合金の材質も、何等限定されるものではなく、リム１０を与えるアルミニウム合金と同様に、目的とする２ピースホイールの要求品質等に応じて、適宜に決定されるのである。
【００２８】
そして、かかるリム１０とディスク１２とを一体的に接合するに際しては、図３に示されるように、リム１０の内孔内にディスク１２が挿入されて、ディスク１２の円筒状フランジ部２０の外周面が、リム１０の円筒状接合部１４の重合面１６に重ね合わされるように、ディスク１２がリム１０に対して嵌め合わされるのである。そして、そのような嵌合状態下において、円筒状接合部１４と円筒状フランジ部２０との重ね合わせ部分２２における、リム１０の意匠面１８側の部位が、摩擦撹拌接合操作により、重ね合わせ接合される。なお、ここでは、円筒状接合部１４と円筒状フランジ部２０との重ね合わせ部分２２における、リム１０の意匠面１８側とは軸方向において反対側となる部位も、摩擦撹拌接合操作により、重ね合わせ接合されることとなる。
【００２９】
すなわち、このリム１０とディスク１２との接合工程では、ロッド状の回転治具２４の先端に同心的に設けたピン２６が、かかる回転治具２４と共に、その軸心回りに一体的に高速回転せしめられつつ、円筒状接合部１４と円筒状フランジ部２０との重ね合わせ部分２２における、リム１０の意匠面１８側となる軸方向一端部側の部位に対して、円筒状接合部１４の外周面側から差し込まれ、更に、図３に二点鎖線で示されるように、かかるピン２６が、円筒状接合部１４を貫通して、円筒状フランジ部２０の所定の深さに達し、且つ回転治具２４の下部が、円筒状接合部１４の外周面に当接するまで、差し込まれる。これによって、高速回転せしめられるピン２６及び回転治具２４の下部と、かかるピン２６が差し込まれる重ね合わせ部分２２における軸方向一端部側部位との間に摩擦熱が発生し、その摩擦熱にて、重ね合わせ部分２２におけるリム１０の意匠面１８側の部位が可塑化せしめられると共に、ピン２６の高速回転に伴う撹拌作用により、かかる重ね合わせ部分２２の軸方向一端部側部位における円筒状接合部１４と円筒状フランジ部２０の組織が互いに入り交じり合わされるのである。
【００３０】
そして、重ね合わせ部分２２の軸方向一端部側部位に差し込んだピン２６が、かかる重ね合わせ部分２２に対して、その周方向に相対的に移動せしめられることにより、組織が入り交じり合わされた円筒状接合部１４と円筒状フランジ部２０にて、接合部が、重ね合わせ部分２２の軸方向一端部側部位において、その周方向に延びるように形成され、以て、リム１０の円筒状接合部１４とディスク１０の円筒状フランジ部２０との重ね合わせ部分２２が、リム１０の意匠面１８側となる軸方向一端部側部位において、摩擦撹拌接合操作により、重ね合わせ接合されるのである。
【００３１】
また、本工程では、回転治具２４のピン２６が、回転治具２４と共に高速回転せしめられつつ、円筒状接合部１４と円筒状フランジ部２０との重ね合わせ部分２２における、リム１０の意匠面１８とは軸方向において反対側となる軸方向他端部側の部位に対しても、円筒状接合部１４の外周面側から差し込まれ、更に、図３に二点鎖線で示されるように、かかるピン２６が、円筒状接合部１４を貫通して、円筒状フランジ部２０の所定の深さに達し、且つ回転治具２４の下部が、円筒状接合部１４の外周面に当接するまで、差し込まれる。そして、そのような状態下において、ピン２６が、重ね合わせ部分２２に対して、その周方向に相対移動せしめられる。これによって、重ね合わせ部分２２の軸方向他端部側部位に対して、軸方向一端部側部位に形成された接合部と同様な接合部が形成され、以て、リム１０の円筒状接合部１４とディスク１２の円筒状フランジ部２０との重ね合わせ部分２２が、その軸方向他端部側部位においても、摩擦撹拌接合操作により、重ね合わせ接合されるのである。
【００３２】
かくして、本工程で、リム１０の円筒状接合部１４とディスク１２の円筒状フランジ部２０との重ね合わせ部分２２が、リム１０の意匠面１８側の部位と、それとは軸方向において反対側となる部位の二箇所において、摩擦撹拌接合操作により、重ね合わせ接合せしめられることによって、リム１０とディスク１２とが、一体的に接合され、以て、目的とする２ピースホイールが得られることとなるのである。
【００３３】
なお、このようなリム１０とディスク１２の摩擦撹拌接合操作による重ね合わせ接合を行なう際には、図示されてはいないものの、必要に応じて、ディスク１２の円筒状フランジ部２０における、前記回転治具２４のピン２６が差し込まれる部分の内側に、適当な裏当て部材が、円筒状フランジ部２０に接触して配置される。これによって、リム１０の円筒状接合部１４やディスク１２の円筒状フランジ部２０へのピン２６の差込み時に、その押圧力（差込み荷重）によって、それら円筒状接合部１４や円筒状フランジ部２０が変形せしめられるようなことが、有利に防止され得るばかりでなく、かかる裏当て部材とピン２６との間で、円筒状接合部１４と円筒状フランジ部２０との重ね合わせ部分２２が挟圧保持されて、摩擦撹拌接合操作の実施時におけるリム１０とディスク１２との位置ずれの発生も、効果的に阻止され得ることとなる。
【００３４】
このように、本実施形態では、ディスク１２の円筒状フランジ部２０の外周面が、リム１０の円筒状接合部１４の重合面１６に重ね合わされるように、ディスク１２をリム１０に対して嵌め合わせた状態下で、円筒状フランジ部２０と円筒状接合部１４との重ね合わせ部分２２における、リム１０の意匠面１８側の部位とその反対側の部位、つまり、かかる重ね合わせ部分２２における軸方向両端部側部位を、それぞれ摩擦撹拌接合して、リム１０とディスク１２とを一体化するものであるところから、リム１０とディスク１２との重ね合わせ部分２２における軸方向両端部側部位の二箇所に、接合部が形成され得ることとなり、それによって、例えば、重ね合わせ部２２の一箇所の部位を、所定の接合操作により接合する場合よりも、リム１０とディスク１２とが、より強固に接合され得るのであり、また、摩擦撹拌接合特有の効果であるところの入熱による接合部の強度低下や歪み等の接合不良の発生の防止効果が有利に享受され得て、リム１０とディスク１２とが、優れた接合品質をもって、極めて有利に接合され得るのである。
【００３５】
しかも、このような本実施形態においては、リム１０とディスク１２との重ね合わせ部分２２における、リム１０の意匠面１８側の部分とその反対側の部分にそれぞれ形成される接合部が、何れも、重ね合わせ接合によって形成されるようになっているところから、それぞれの接合部において、例えば、突き合わせ接合や隅肉接合にて形成される接合部よりも優れた接合強度が得られ、これによっても、リム１０とディスク１２とが、より強固に接合され得るのであり、また、重ね合わせ接合にて形成された各接合部の表面が、タイヤ等が嵌め込まれるリム１０の外周面に形成されることとなるため、リム１０とディスク１２とが、それらの重ね合わせ部分２２におけるリム１０の意匠面１８側の端部において接合されているにも拘わらず、リム１０の意匠面１８に、接合部が露呈せしめられるようなことが有利に回避され得るのである。
【００３６】
従って、かくの如き本実施形態に係る２ピースホイールの製造手法によれば、リム１０の意匠面１８の意匠性を何等損なうことなく、リム１０とディスク１２とが、より強固に且つ確実に接合され得、以て、接合不良のない、優れた接合品質と強度とを有する高品質の２ピースホイールが、極めて有利に製造され得ることとなるのである。
【００３７】
また、本実施形態においては、前述せる如く、リム１０の円筒状接合部１４とディスク１２の円筒状フランジ部２０との重ね合わせ部分２２における軸方向両端部側部位に対して、円筒状接合部１４の外周面側から、高速回転せしめられるピン２６を差し込んで摩擦撹拌接合を行なう際に、必要に応じて、適当な裏当て部材を円筒状フランジ部２０の内側に配置するだけで、円筒状接合部１４と円筒状フランジ部２０の変形やそれらの位置ずれが阻止され得るようになっているところから、摩擦撹拌接合時におけるリム１０とディスク１２の保持操作が、極めて容易に実施され得るのである。
【００３８】
ところで、前記実施形態では、リム１０の円筒状接合部１４とディスク１２の円筒状フランジ部２０との重ね合わせ部分２２における軸方向両端部側部位に対して、回転治具２４と共に高速回転せしめられるピン２６が、円筒状接合部１４の外周面側から円筒状フランジ部２０に達するように差し込まれて、周方向に相対移動せしめられる摩擦撹拌接合操作による重ね合わせ接合が行なわれることによって、それら重ね合わせ部分２２における、リム１０の意匠面１８側の部位と、該意匠面１８とは反対側の部位とが、一体的に接合されるようになっていたが、本発明手法においては、少なくとも、重ね合わせ部分２２における、リム１０の意匠面１８側の部位に対して、摩擦撹拌接合操作による重ね合わせ接合が行なわれておれば良いのであって、重ね合わせ部分２２における、リム１０の意匠面１８側とは反対側の部位が、必ずしも摩擦攪拌接合操作によって接合されている必要はなく、また、かかる部位を接合するに際しても、その接合方式が、特に限定されるものではないのである。
【００３９】
従って、例えば、図４に示されるように、リム１０の円筒状接合部１４とディスク１２の円筒状フランジ部２０との重ね合わせ部分２２における、リム１０の意匠面１８側の部位に対して、前記実施形態と同様な摩擦撹拌接合操作による重ね合わせ接合が行なわれる一方、かかる重ね合わせ部分２２における、リム１０の意匠面１８側とは軸方向において反対側となる部位に対して、高速回転せしめられるピン２６が、リム１０の意匠面１８側とは反対側から、円筒状接合部１４と円筒状フランジ部２０との重ね合わせ面間に、それら円筒状接合部１４と円筒状フランジ部２０の各端面に対して回転治具２４の下部が当接するまで差し込まれ、そして、その差込み状態下で、重ね合わせ部分２２に対して、その周方向に相対移動せしめられることによって、重ね合わせ部分２２における、リム１０の意匠面１８側とは反対側の部位が摩擦撹拌接合されるように為しても良いのである。
【００４０】
このような本実施形態手法にあっても、円筒状接合部１４と円筒状フランジ部２０の重ね合わせ部分２２における、リム１０の意匠面１８側の部位とそれとは反対側の部位において、リム１０に対するタイヤの装着状態下や、２ピースホイールの自動車への装着状態下で、外部から視認不能な二箇所が摩擦撹拌接合されて、リム１０とディスク１２とが一体的に接合されており、また、特に、重ね合わせ部分２２における、リム１０の意匠面１８側の部位が、重ね合わせ接合されるようになっているところから、前記第一の実施形態と同様な効果が、有利に享受され得るのである。
【００４１】
また、上述の如く、重ね合わせ部分２２における、リム１０の意匠面１８側とは反対側の部位に対して、摩擦撹拌接合操作による突き合わせせ接合を行なう場合にあっては、有利には、図５に示される如く、ディスク１２が、円筒状フランジ部２０に突起２８を有して構成される一方、リム１０が、円筒状接合部１４に係合凹部３０を有して構成されることとなる。
【００４２】
すなわち、ここでは、ディスク１２の円筒状フランジ部２０の先端側外周面に対して、径方向に所定高さ突出し、且つ周方向に連続して延びる突条形態を呈する突起２８が、一体的に形成されており、また、かかる突起２８の二つの側面のうち、円筒状フランジ部２０の基部側、つまりディスク１２の意匠面１８側に位置する側面が、軸方向に対して直角な方向に広がる円環形状を呈する係合面３２として、構成されている。
【００４３】
一方、リム１０の円筒状接合部２０の重合面１６において、ディスク１２の突起２８の形成側部位に対応する部位には、係合凹部３０が、かかる突起２８が嵌入可能な状態で、周方向に連続して延びる切欠溝形態をもって、形成されている。また、かかる係合凹部３０にあっては、突起２８の嵌入状態下で、該突起２８の係合面３２と接触する側面が、かかる係合面３２に対応した形状を有すると共に、該係合面３２に対して軸方向に係合する係合面３４とされている。
【００４４】
そして、本実施形態において、リム１０とディスク１２とを一体的に接合する際には、先ず、ディスク１２における円筒状フランジ部２０の突起２８が、リム１０における円筒状接合部１４の係合凹部３０に嵌入せしめられて、該突起２８の係合面３２が係合凹部３０の係合面３４に係合しつつ、円筒状フランジ部２０の外周面と円筒状接合部１４の重合面１６とが互いに重ね合わされることによって、ディスク１２のリム１０に対する意匠面１８側への相対移動が阻止された状態で、ディスク１２がリム１０に嵌め合わされる。その後、前述せるように、円筒状フランジ部２０と円筒状接合部１４の重ね合わせ部分２２における、リム１０の意匠面１８側の部位が、摩擦撹拌接合操作により重ね合わせ接合される一方、それとは反対側の部位が、摩擦撹拌接合操作により突き合わせ接合されることとなる。
【００４５】
このような本実施形態手法によれば、円筒状フランジ部２０と円筒状接合部１４の重ね合わせ部分２２における、リム１０の意匠面１８側とは反対側の部位が摩擦撹拌接合により突き合わせ接合される際に、回転治具２４と共に高速回転せしめられるピン２６の押圧力にて、円筒状フランジ部２０と円筒状接合部１４の重ね合わせ位置の軸方向へのズレが有利に防止され得るのであり、それによって、リム１０とディスク１２とが、常に一定の位置で接合された２ピースホイールが有利に製造され得ることとなるのである。
【００４６】
なお、ここでは、ディスク１２における円筒状フランジ部２０の外周面に対して、突起２８が、周方向に連続して延びる一つの突条形態をもって、一体形成される一方、リム１０の円筒状接合部１４の重合面１６に、係合凹部３０が、かかる突起２８が嵌入可能な、周方向に連続して延びる切欠溝形態をもって形成されていたが、突起２８を、円筒状フランジ部２０の外周面に対して、周方向に断続的に延びる幾つかの突条形態か、若しくは周方向に延出せしめられることなく、周方向に所定の距離を隔てた位置において、互いに独立して突出する山状形態をもって形成する一方、係合凹部３０を、そのような突起２８の形態にそれぞれ対応した凹溝形態若しくは凹所形態をもって形成することも、可能である。
【００４７】
また、かくの如き突起２８を、リム１０における円筒状接合部１４の重合面１６に形成する一方、係合凹部３０を、ディスク１２における円筒状フランジ部２０の外周面に形成したり、或いは、それら突起２８と係合凹部３０とを、リム１０における円筒状接合部１４の重合面１６とディスク１２における円筒状フランジ部２０の外周面の両方に形成したりしても、良いのである。
【００４８】
更に、突起２８における前記係合面３２と先端面とにて形成される角部を、角張った形状ではなく、湾曲面形態をもって形成しても良いが、その際には、かかる角部の湾曲面の曲率半径が５ｍｍ以下とされていることが、望ましい。それによって、突起２８と前記係合凹部３０との係合状態が、より安定的に確保され得るのである。
【００４９】
また、上述せる如き手法とは異なって、図６に示されるように、円筒状フランジ部２０の先端部に、先端に向かうに従って次第に大径化するテーパ状内周面３６が形成されたディスク１２を用いて、目的とする２ピースホイールを得ることも、可能である。
【００５０】
すなわち、この円筒状フランジ部２０の先端部にテーパ状内周面３６が形成されたディスク１２を用いる場合には、先ず、前記せる幾つかの実施形態と同様に、ディスク１２における円筒状フランジ部２０の外周面とリム１０における円筒状接合部１４の重合面１６とが互いに重ね合されるように、ディスク１０がリム１０に対して嵌め合わされる。その後、円筒状フランジ部２０と円筒状接合部１４との重ね合わせ部分２２における、リム１０の意匠面１８側の部位が、前記実施形態と同様にして、摩擦撹拌接合操作により重ね合わせ接合せしめられる。そして、その一方で、重ね合わせ部分２２における、リム１０の意匠面１８側とは反対側の部位に対して、回転治具２４と共に高速回転せしめられるピン２６が、円筒状フランジ部２０の先端部のテーパ状内周面３６から斜めに差し込まれ、更に、かかるピン２６が、円筒状フランジ部２０を貫通して、円筒状接合部１４の所定の深さに達するまで、差し込まれる。そして、そのような差込み状態下において、ピン２６が、円筒状フランジ部２０と円筒状接合部１４の重ね合わせ部分２２に対して、その周方向に相対移動せしめられる。
【００５１】
かくして、円筒状フランジ部２０と円筒状接合部１４との重ね合わせ部分２２における、リム１０の意匠面１８側の部位とそれとは反対側の部位とが、それぞれ、摩擦撹拌接合操作により重ね合わせ接合せしめられて、リム１０とディスク１２とが一体的に接合され、以て、目的とする２ピースホイールが得られることとなるのである。
【００５２】
このような本実施形態手法にあっても、円筒状接合部１４と円筒状フランジ部２０の重ね合わせ部分２２における、リム１０の意匠面１８側の部位とそれとは反対側の部位において、リム１０に対するタイヤの装着状態下や、２ピースホイールの自動車への装着状態下で、外部から視認不能な二箇所に、接合部が、摩擦撹拌接合操作による重ね合わせ接合によって形成されるようになっているところから、前記第一の実施形態と同様な効果が、有利に享受され得るのである。
【００５３】
なお、かくの如き本実施形態手法を採用する場合にあっては、有利には、ディスク１２の円筒状フランジ部２０の先端部に形成されたテーパ状内周面３６が、６０〜１２０°の範囲内のテーパ角度を有するように構成される。何故なら、かかるテーパ角度が６０°よりも小さい場合には、回転治具２４と共に高速回転せしめられるピン２６が、円筒状接合部１４と円筒状フランジ部２０の重ね合わせ部分２２における、リム１０の意匠面１８側とは反対側の部位に対して、テーパ状内周面３６から斜めに差し込まれて、周方向に相対移動せしめられることにより、摩擦撹拌接合操作が実施される際に、ピン２６と回転治具２４の差込み方向が、軸方向に対して、より直角に近い方向となるため、回転治具２４やそれに取り付けられるモータ等が、重ね合わせ部分２２における、ピン２６が差し込まれるる部位とは径方向の反対側の部分等に干渉せしめられて、摩擦撹拌接合操作の円滑な進行が妨げられる恐れがあるからであり、また、テーパ状内周面３６のテーパ角度が１２０°よりも大きい場合には、逆に、摩擦撹拌接合操作を行なう際におけるピン２６と回転治具２４の差込み方向が、軸方向に対して、より平行に近い方向となるため、重ね合わせ部分２２における、リム１０の意匠面１８とは反対側の部位に対して、ピン２６を、テーパ状内周面３６から円筒状接合部１４の所定の深さにまで達するように差し込むことが困難となり、そのために、かかる部位に形成される接合部において、充分な接合強度が得られなくなってしまう恐れがあるからである。
【００５４】
従って、ここでは、ディスク１２の円筒状フランジ部２０の先端部に形成されたテーパ状内周面３６が、６０〜１２０°の範囲内のテーパ角度を有するように構成されることによって、回転治具２４のピン２６が、円筒状フランジ部２０のテーパ状内周面３６からリム１０の円筒状接合部１４に達するように、確実に差し込まれ得て、それら円筒状フランジ部２０と円筒状接合部１４の重ね合わせ部分２２における、リム１０の意匠面１８側とは反対側の部位が、より有利に且つ確実に重ね合わせ接合せしめられ得るのであり、その結果として、リム１０とディスク１２とが優れた接合強度をもって一体的に接合されてなる２ピースホイールが、安定的に且つ確実に製造され得ることとなるのである。
【００５５】
また、そのように、ディスク１２の円筒状フランジ部２０の先端部にテーパ状内周面３６を形成する場合には、少なくとも、かかる先端部における、回転治具２４と共に高速回転せしめられるピン２６が差し込まれる部位がテーパ状内周面３６とされておれば、必ずしも、かかる先端部の全周に亘って、テーパ状内周面３６が形成されている必要はない。即ち、かかる先端部に対して、テーパ状内周面３６が、部分的に形成されていても良いのである。
【００５６】
以上、本発明の具体的な構成について、幾つかの実施形態を示しつつ、詳述してきたが、それらはあくまでも例示に過ぎないのであって、本発明は、上記の記載によって、何等の制約をも受けるものではない。
【００５７】
例えば、前記せる幾つかの実施形態では、リム１０の円筒状接合部１４とディスク１２の円筒状フランジ部２０との重ね合わせ部分２２における、リム１０の意匠面１８側の部位とそれとは反対側の部位のうち、先ず、リム１０の意匠面１８側の部位が接合された後、それとは反対側の部位が接合されるようになっていたが、その接合順序は、何等限定されるものではなく、重ね合わせ部分２２における、リム１０の意匠面１８側の部位を先に接合したり、或いはそれら二つの部位を同時に接合したりしても、良いのである。
【００５８】
さらに、前記実施形態では、リム１０の円筒状接合部１４とディスク１２の円筒状フランジ部２０との重ね合わせ部分２２における、リム１０の意匠面１８側の部位とそれとは反対側の部位とが、何れも、摩擦撹拌接合操作によって、接合されていたが、かかる重ね合わせ部分２２における、リム１０の意匠面１８とは反対側の部位を、例えば、アーク溶接等の溶融溶接によって接合することも、可能なのである。
【００５９】
更にまた、リム１０やディスク１２の形状も、特に限定されるものではなく、円筒状接合部１４や円筒状フランジ部２０が設けられてなるものであれば、例示されるもの以外の形状も、適宜に採用され得るのである。
【００６０】
加えて、前記せる全ての実施形態では、自動車用２ピースホイールの製造方法に対して、本発明を適用したものの具体例を示したが、本発明は、その他、自動車以外の車両に用いられる２ピースホイールの何れに対しても、有利に適用され得るものであることは、勿論である。
【００６１】
その他、一々列挙はしないが、本発明は、当業者の知識に基づいて種々なる変更、修正、改良等を加えた態様において実施され得るものであり、また、そのような実施態様が、本発明の趣旨を逸脱しない限り、何れも、本発明の範囲内に含まれるものであることは、言うまでもないところである。
【００６２】
【発明の効果】
以上の説明からも明らかなように、本発明に従う２ピースホイールの製造方法によれば、リムの意匠面の意匠性を何等損なうことなく、リムとディスクとを、より簡単な摩擦撹拌接合操作にて、更に一層信頼性の高い接合強度をもって容易に接合することが出来、以て優れた品質と充分な強度とを有する高品質のピースホイールを極めて有利に製造することが可能となるのである。
【図面の簡単な説明】
【図１】本発明手法に従って、２ピースホイールを製造する際に用いられるリムの一例を示す半截説明図である。
【図２】本発明手法に従って、２ピースホイールを製造する際に用いられるディスクの一例を示す縦断面説明図である。
【図３】本発明手法に従って、２ピースホイールを製造する工程の一例を示す説明図であって、リムの円筒状接合部とディスクの円筒状フランジ部との重ね合わせ部分における、リムの意匠面側の部位とそれとは反対側の部位に対して、摩擦撹拌接合操作による重ね合わせ接合をそれぞれ行なっている状態を示している。
【図４】本発明手法に従って、２ピースホイールを製造する工程の別の例を示す説明図であって、リムの円筒状接合部とディスクの円筒状フランジ部との重ね合わせ部分における、リムの意匠面側の部位に対して、摩擦撹拌接合操作による重ね合わせ接合を行なう一方、それとは反対側の部位に対して、摩擦撹拌接合操作による突き合わせ接合を行なっている状態を示している。
【図５】本発明手法に従って、２ピースホイールを製造する工程の更に別の例を示す説明図であって、外周面に突起が設けられた円筒状フランジ部を有するディスクと、重合面に係合凹部が設けられた円筒状接合部を有するリムとを用いて、それら円筒状接合部と円筒状フランジ部との重ね合わせ部分における、リムの意匠面側の部位に対して、摩擦撹拌接合操作による重ね合わせ接合を行なう一方、それとは反対側の部位に対して、摩擦撹拌接合操作による突き合わせ接合を行なっている状態を示している。
【図６】本発明手法に従って、２ピースホイールを製造する工程の他の例を示す説明図であって、円筒状フランジ部の先端部にテーパ状内周面が形成されたディスクを用いて、リムの円筒状接合部とディスクの円筒状フランジ部との重ね合わせ部分における、リムの意匠面側の部位とそれとは反対側の部位に対して、摩擦撹拌接合操作による重ね合わせ接合をそれぞれ行なっている状態を示している。
【符号の説明】
１０リム１２ディスク
１４円筒状接合部１６重合面
１８意匠面２０円筒状フランジ部
２２重ね合わせ部分２４回転治具
２６ピン２８突起
３０係合凹部３２，３４係合面
３６テーパ状内周面[0001]
【Technical field】
The present invention relates to a method for manufacturing a two-piece wheel, and more particularly to an advantageous method for manufacturing a two-piece wheel in which an aluminum alloy rim and a disk are integrally joined.
[0002]
[Background]
As is well known, in recent years, a wheel made of an aluminum alloy having excellent lightness and design has been frequently used as a vehicle wheel for an automobile or the like. As a kind of such a wheel, an aluminum alloy rim is provided, and an aluminum alloy disc having a design surface on one side is fitted into the rim and integrally joined. A so-called two-piece wheel is known.
[0003]
By the way, this two-piece wheel made of aluminum alloy is generally disclosed in, for example, JP-A-2001-88504, etc., and the disk is generally disposed in the inner hole of the rim having a substantially cylindrical shape as a whole. Part of the outer peripheral surface is butted or overlapped with the inner peripheral surface of the rim, and the rim and the disc are butted together by a fusion welding operation such as arc welding under the fitted state. Are joined together, such as by butt joining at the part, or by fillet joining at the fillet part formed in the overlapped part. When joining the disk by fusion welding operation, problems such as a decrease in strength and distortion of the joint due to the great heat input during welding may occur. It was not kicked.
[0004]
  On the other hand, in Japanese translations of PCT publication No. 2000-509342, a rim and a disk are joined together by a friction stir welding operation instead of a fusion welding operation.InA method for manufacturing such a two-piece wheel has been disclosed. Here, as is well known, the friction stir welding operation used for joining the rim and the disk is a joining in a solid phase state without melting any part to be joined. The heat input during joining can be effectively reduced. Therefore, according to the two-piece wheel manufacturing method disclosed in the publication, problems such as a decrease in strength of the joint and occurrence of distortion that occur when the rim and the disk are joined by a fusion welding operation are advantageously solved. It can be done.
[0005]
However, in the conventional two-piece wheel manufacturing method disclosed in the above-mentioned publication in which the rim and the disk are friction stir welded, the same method as the two-piece wheel manufacturing method in which the rim and the disk are melt welded is used. In addition, the rim and the disc are abutted at the abutting portion in a state where the disc is fitted or overlapped with the inner circumferential surface of the rim at a part of the outer circumferential surface thereof. Since the fillet is joined at the fillet formed in the overlapped part, the joint strength between the rim and the disk is not reduced by the influence of heat input, but the joint is joined. It was difficult to say that the strength was sufficiently satisfactory.
[0006]
Also, in such a conventional method, a pin provided concentrically at the tip of a rod-shaped rotating jig is rotated at a high speed together with the rotating jig, while the rim and disk are brought into contact with each other or between the overlapping surfaces. The friction stir welding operation is performed by inserting and moving the rim and the disk relative to each other. In this case, in order to prevent deformation of the parts to be joined between the rim and the disk, In addition to holding the disc and the disc from the direction opposite to the direction in which the pressing force is applied so as to counter the pressing force applied from the pin, in order to prevent misalignment between the rim and the disc, In order to prevent the abutting surfaces and the overlapping surfaces of the two from being separated from each other, it must be held from another direction. In addition, when performing fillet joining to the fillet portion of the overlapping portion of the rim and disk, the fillet portion is formed on the design surface side of the rim. The surface of the joint portion is formed on the design surface of the rim that is visually recognized from the outside, thereby impairing the design property of the design surface of the rim and seriously reducing the quality of the target two-piece wheel. Problems will be raised.
[0007]
[Solution]
Here, the present invention has been made in the background of the circumstances as described above, and the problem to be solved is that the design surface of the rim is obtained by performing a simpler friction stir welding operation between the rim and the disk. It is an object of the present invention to provide a method for advantageously producing a piece wheel that can be easily joined with a sufficient joining strength without impairing the design properties of the steel, and that has excellent quality and strength.
[0008]
[Solution]
  In the present invention, in order to solve such a problem, an aluminum alloy disc having a design surface on one side is fitted to and integrally joined to a rim made of an aluminum alloy material. When the two-piece wheel is manufactured, the disk is provided with a cylindrical flange portion that extends toward the direction away from the design surface on the side opposite to the design surface at the outer peripheral edge portion. As the rim, an inner peripheral surface having a cylindrical joint portion overlapped with the outer peripheral surface of the cylindrical flange portion of the disk is used, and the outer peripheral surface of the cylindrical flange portion is used. After the disc is fitted to the rim so that the overlapping surfaces of the cylindrical joint are overlapped with each other, the cylindrical flange portion of the disc and the cylindrical joint of the rim A pin provided concentrically at the tip of the rod-shaped rotating jig with respect to the design surface side portion of the disk in the overlapping portion with the rotating jig, From the outer peripheral surface side of the cylindrical joining portion, the disc is inserted so as to reach the cylindrical flange portion of the disc, and moved relatively in the circumferential direction, thereby friction stir the site on the design surface side of the disc in the overlapped portion. JoinIn addition, in the overlapping portion of the cylindrical flange portion of the disc and the cylindrical joint portion of the rim, predetermined joining is performed with respect to a portion that is opposite to the design surface side portion of the disc in the disc axial direction. The operation was carried out, and the rim and the disk were integrally joined to each other at the axial end portions of the overlapping portion.The gist of the two-piece wheel manufacturing method is characterized by the above.
[0009]
In short, in the method of manufacturing a two-piece wheel according to the present invention, the cylindrical flange portion provided on the disk and the cylindrical joint portion provided on the rim are overlapped with each other, and the cylindrical flange portions are overlapped with each other. A pin that can be rotated together with the rotating jig from the outer peripheral surface side of the cylindrical joint portion to the cylindrical flange portion on the design surface side of the rim in the overlapping portion of the cylindrical joint portion and the cylindrical joint portion. By inserting it so as to reach it and moving it relatively in the circumferential direction, the design surface side portion of the rim in the overlapped portion is friction stir welded.
[0010]
Therefore, in such a two-piece wheel manufacturing method according to the present invention, the joint between the rim and the disk formed by friction stir welding is different from the case where it is formed by fusion welding. Not only can the adverse effects of heat be advantageously avoided, but it is formed by lap joints to the lap part and fillet part, which provides better joint strength than butt joints and fillet joints. As a result, a more excellent bonding strength can be secured sufficiently in such a bonded portion.
[0011]
Further, in the method of manufacturing a two-piece wheel according to the present invention, the pin that is rotated integrally with the rotating jig together with the rotating jig is moved from the outer peripheral surface side of the cylindrical joint portion to the cylindrical flange portion that is superimposed on the pin. The surface of the joint formed by such a friction stir welding operation is the outer surface of the rim into which the tire or the like is fitted. As a result, the surface of the joint is exposed to the design surface of the rim, even though the rim and the disk are joined at the end on one axial side that is the design surface side of the rim. This can be effectively avoided.
[0012]
In addition, in such a method of the present invention, as described above, the pin that is rotated together with the rotating jig has an outer peripheral surface of the cylindrical joint portion with respect to the overlapping portion of the cylindrical joint portion and the cylindrical flange portion. Since the friction stir welding operation is performed by being inserted so as to reach the cylindrical flange portion, for example, when the friction stir welding operation is performed, the rim and the disk are simply operated from the pin. In order to counter the pressing force to be squeezed, it is possible to prevent the overlapping portion of the rim and the disk from being deformed by the pressing force only by holding from the direction opposite to the direction in which the pressing force is applied. Is in a state of being sandwiched between a predetermined holding member that holds them and the pin, and the positional deviation between the rim and the disk can be effectively prevented, Thus, for example, the rim at the time of the friction stir welding operation is performed rather than the butt joint or fillet joint in which the rim and the disk must be held from a direction other than the direction opposite to the pressing direction by the pin. Thus, the disk holding operation, and hence the friction stir welding operation, can be advantageously simplified.
[0013]
Therefore, according to the method of manufacturing a two-piece wheel according to the present invention as described above, the rim and the disk can be more reliably connected by a simpler friction stir welding operation without any loss in the design of the design surface of the rim. Therefore, a high-quality piece wheel having excellent quality and sufficient strength can be manufactured very advantageously.
[0014]
  in addition, A method of manufacturing such a two-piece wheel according to the present inventionTo the lawAccording to the present invention, a predetermined joining operation is performed on a portion of the overlapping portion of the cylindrical flange portion of the disc and the cylindrical joint portion of the rim that is opposite to the design surface side portion of the disc in the axial direction. Is implemented, and the rim and the disk are integrally joined to each other at both axial end portions of the overlapping portion.But,As a result, joint portions are formed at two positions in the axial direction in the overlapping portion of the rim and the disk, and thus the joint strength between the rim and the disk can be further effectively increased.
[0015]
According to another advantageous aspect of the method of manufacturing a two-piece wheel according to the present invention, the design of the disc in the overlapping portion of the cylindrical flange portion of the disc and the cylindrical joint portion of the rim. While the pin provided concentrically at the tip of the rod-shaped rotating jig is rotated together with the rotating jig with respect to the part opposite to the surface side in the axial direction, the cylindrical shape of the rim By inserting from the outer peripheral surface side of the joint portion so as to reach the cylindrical flange portion of the disk and moving it relatively in the circumferential direction, the portion of the overlapping portion opposite to the design surface side is friction stir The joining method is adopted.
[0016]
If such a configuration is adopted, the joint formed on the side of the rim and disk that is on the opposite side of the design surface side of the rim is the same as the joint formed on the side of the design surface of the rim. In addition, it is possible to easily form with excellent joint strength by superposition joining by a simple friction stir welding operation, whereby the rim and the disk can be joined more firmly, and even higher. A two-piece wheel with quality can be advantageously manufactured.
[0017]
Furthermore, according to one of the other desirable aspects of the manufacturing method of the two-piece wheel according to this invention, the design surface of the said disk in the overlapping part of the cylindrical flange part of the said disk and the cylindrical junction part of a rim | limb. A pin provided concentrically at the tip of a rod-shaped rotating jig between the overlapping surfaces of the parts opposite to the side part in the axial direction is rotated together with the rotating jig, By inserting from the side opposite to the design surface side and relatively moving in the circumferential direction, the portion of the overlapping portion on the side opposite to the design surface side is friction stir welded. As a result, the surfaces of the joint portions formed at both ends in the axial direction of the overlapping portion of the rim and the disk are not visible from the outside when the outer peripheral surface of the rim and the wheel are mounted on an automobile or the like. Thus, it is formed on the surface opposite to the design surface, and thus the excellent design properties of the rim and, consequently, the entire two-piece wheel can be more advantageously ensured.
[0018]
As such, in the two-piece wheel manufacturing method according to the present invention, the pin provided on the rotating jig is overlapped at the overlapping portion of the cylindrical flange portion of the disk and the cylindrical joint portion of the rim under rotation. When the portion of the overlapped portion, which is opposite to the design surface side of the rim, is inserted between the mating surfaces from the side opposite to the design surface side and friction stir welding is preferably performed, A protrusion projecting in the radial direction is provided on at least one of the outer peripheral surface of the cylindrical flange portion and the overlapping surface of the cylindrical joint portion in the rim, and at least one of them is provided with the protrusion By engaging with the rim, there is provided an engaging recess for preventing relative movement of the disk relative to the rim toward the design surface side of the rim.
[0019]
In the method of manufacturing a two-piece wheel having such a configuration, the protrusion provided on at least one of the cylindrical flange portion and the cylindrical joint portion is provided on at least one of them. Positioning in a state where the disc and the rim are engaged with each other by fitting the disc and the rim while overlapping each other at the cylindrical flange portion and the cylindrical joint portion while being engaged with the engaging recess. Can be easily performed, and while rotating the pin of the rotating jig, it is inserted from the side opposite to the design surface side of the disk and moved relatively, so that the cylindrical flange portion and the cylindrical joint portion can be moved. Relative movement of the rim to the design surface side of the rim with respect to the rim of the disk is advantageous when performing friction stir welding on the opposite side of the rim design surface side in the overlapped portion Sealed obtained, Te than the disk and the rim is always of a possible two-piece joined at a certain position can be advantageously produced.
[0020]
According to another preferred embodiment of the method for manufacturing a two-piece wheel according to the present invention, a tapered inner peripheral surface that gradually increases in diameter toward the tip is formed at the tip of the cylindrical flange portion of the disk. In the state in which the cylindrical flange portion of the disk and the cylindrical joint portion of the rim are overlapped with each other, the rod-shaped rotating jig is against the tapered inner peripheral surface of the cylindrical flange portion. A pin provided concentrically at the tip is inserted obliquely so as to reach the cylindrical joint from the tapered inner peripheral surface while rotating together with the rotating jig, and relatively moved in the circumferential direction. Thus, the friction stir welding is performed on a portion of the overlapping portion of the cylindrical flange portion of the disc and the cylindrical joint portion of the rim that is opposite to the design surface side portion of the disc in the axial direction. And thus.
[0021]
In such a two-piece wheel manufacturing method according to the present invention, in the overlapping portion of the cylindrical flange portion and the cylindrical joint portion, similarly to the portion on the design surface side of the rim, it is on the opposite side in the axial direction. This part is also superposed and joined by a friction stir welding operation in which the holding operation of the rim and the disk is relatively easy, so that the part on the opposite side of the design surface side of the rim in the superposed part is formed. On the other hand, a joint having excellent joint strength can be easily formed, so that the rim and the disk can be joined more firmly and easily, and an even higher quality two-piece wheel is advantageously manufactured. It can be done.
[0022]
In addition, in the method of manufacturing a two-piece wheel according to the present invention, in the case of using a disk in which a tapered inner peripheral surface gradually increasing in diameter toward the tip is used at the tip of the cylindrical flange portion. , Advantageously, the tapered inner peripheral surface at the tip of the cylindrical flange portion is configured with a taper angle in the range of 60-120 °. If such a configuration is adopted, the pin of the rotating jig can be reliably inserted into the tapered inner peripheral surface at the tip of the cylindrical flange portion, and the cylindrical flange portion and the cylindrical joint portion are overlapped. The portion of the mating portion opposite to the design surface side of the rim can be more advantageously and reliably overlapped and bonded, and as a result, the rim and the disk are integrally bonded with excellent bonding strength. The two-piece wheel thus formed can be manufactured stably.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
By the way, when manufacturing a two-piece wheel for an automobile, for example, by using the two-piece wheel manufacturing method according to the present invention as described above, first, a rim 10 and a disk 12 as shown in FIGS. 1 and 2 are prepared. The Rukoto.
[0024]
That is, as shown in FIG. 1, the rim 10 prepared here is made of a predetermined aluminum alloy material, and as a whole, is a substantially stepped cylinder whose both end portions are larger in diameter than the intermediate portion in the axial direction. It has a shape. In this case, in particular, the axial intermediate portion having a smaller diameter than both axial end portions is a cylindrical joint portion 14 having a cylindrical wall portion of the same diameter extending straight in the axial direction. In addition, the inner peripheral surface of the cylindrical joint portion 14 is configured as a superposed surface 16 that is superimposed on a cylindrical flange portion (20) of the disk 12 described later (see FIG. 3).
[0025]
In order to manufacture the rim 10 having such a shape, conventionally known methods are appropriately employed. In other words, for example, in a state where a plate material made of an aluminum alloy is bent into a cylindrical shape by roll forming or the like, the butted portions that are butted in the circumferential direction are integrally joined by flash butt welding, friction stir welding, or the like. The tubular body is further subjected to press forming processing such as spinning processing or roll processing, and the rim 10 is formed into a desired shape having a stepped cylindrical shape as a whole. A method of obtaining a rim 10 by forming a cylindrical body made of an aluminum alloy by an extrusion molding operation using an aluminum alloy material and molding the cylindrical body into a desired stepped cylindrical shape, and further from an aluminum alloy The bottomed cylindrical body is formed by drawing the plate material to be formed, and the bottom of the bottomed cylindrical body is removed and placed on both sides in the axial direction. Give the opening to the cylindrical body, further, by forming such a cylindrical body in a cylindrical shape with a desired stage, techniques such as to obtain a rim 10 is as it can be properly adopted. Further, the material of the aluminum alloy for providing the rim 10 is not limited at all, and is appropriately determined according to the required quality of the target two-piece wheel.
[0026]
On the other hand, as shown in FIG. 2, the disk 12 prepared together with the rim 10 is made of a predetermined aluminum alloy, and as a whole, has a substantially thick disk shape that can be fitted into the rim 10. One surface is a design surface 18 provided with a predetermined design. Further, in the disk 12, a cylindrical flange portion 20 having the same diameter extending in a direction away from the design surface 18 on the opposite side to the design surface 18 is integrally formed on the outer peripheral edge thereof. Yes. That is, the disk 12 as a whole has a substantially bottomed cylindrical shape, and the outer surface of the bottom portion is a design surface 18 and the cylindrical wall portion is a cylindrical flange portion 20. It is. Then, the disk 12 is superimposed on the overlapping surface 16 of the cylindrical joint portion 14 of the rim 10 on the outer peripheral surface of the cylindrical flange portion 20 in a state where the disc 12 is fitted in the rim 10. It is designed to be squeezed (see FIG. 3).
[0027]
In addition, the manufacturing method of such a disk 12 is not specifically limited, The method etc. which shape | mold an aluminum alloy material in a predetermined disk shape by casting or forging can be employ | adopted suitably. Also, the material of the aluminum alloy that provides the disk 12 is not limited in any way, and is appropriately determined according to the required quality of the target two-piece wheel, as with the aluminum alloy that provides the rim 10. It is.
[0028]
When the rim 10 and the disk 12 are integrally joined, as shown in FIG. 3, the disk 12 is inserted into the inner hole of the rim 10, and the outer periphery of the cylindrical flange portion 20 of the disk 12 is inserted. The disk 12 is fitted to the rim 10 so that the surface is superimposed on the overlapping surface 16 of the cylindrical joint 14 of the rim 10. And in such a fitting state, the site | part by the side of the design surface 18 of the rim | limb 10 in the overlapping part 22 of the cylindrical junction part 14 and the cylindrical flange part 20 is overlap-joined by friction stir welding operation. Is done. Here, the portion of the overlapping portion 22 of the cylindrical joint portion 14 and the cylindrical flange portion 20 that is opposite to the design surface 18 side of the rim 10 in the axial direction is also overlapped by the friction stir welding operation. They will be joined together.
[0029]
That is, in the joining process of the rim 10 and the disk 12, the pin 26 concentrically provided at the tip of the rod-shaped rotating jig 24 rotates together with the rotating jig 24 at a high speed around the axis. The outer periphery of the cylindrical joint portion 14 with respect to a portion on the axial one end side that is the design surface 18 side of the rim 10 in the overlapping portion 22 of the cylindrical joint portion 14 and the cylindrical flange portion 20 while being fastened. Further, as shown by a two-dot chain line in FIG. 3, the pin 26 penetrates the cylindrical joint portion 14, reaches a predetermined depth of the cylindrical flange portion 20, and rotates. The jig 24 is inserted until the lower part of the jig 24 comes into contact with the outer peripheral surface of the cylindrical joint 14. As a result, frictional heat is generated between the pin 26 rotated at a high speed and the lower part of the rotating jig 24 and the axial one end side portion of the overlapping portion 22 into which the pin 26 is inserted. The portion of the overlapping portion 22 on the side of the design surface 18 of the rim 10 is plasticized and the cylindrical joint portion at the one end side portion in the axial direction of the overlapping portion 22 by the stirring action accompanying the high-speed rotation of the pin 26. 14 and the structure of the cylindrical flange portion 20 are intermingled with each other.
[0030]
And the pin 26 inserted in the axial direction one end side site | part of the superimposition part 22 is moved relatively to the circumferential direction with respect to this superposition part 22, and the cylindrical shape by which the structure | tissue was mixed together. The joining portion 14 and the cylindrical flange portion 20 are formed so that the joining portion extends in the circumferential direction at the axial direction one end side portion of the overlapping portion 22, and thus the cylindrical joining portion 14 of the rim 10. The overlapping portion 22 of the disk 10 and the cylindrical flange portion 20 of the disk 10 is overlap-bonded by a friction stir welding operation at one axial end portion side of the rim 10 on the design surface 18 side.
[0031]
Further, in this step, the design surface of the rim 10 in the overlapping portion 22 of the cylindrical joint portion 14 and the cylindrical flange portion 20 while the pin 26 of the rotary jig 24 is rotated at a high speed together with the rotary jig 24. 18 is also inserted from the outer peripheral surface side of the cylindrical joint portion 14 into a portion on the other end side in the axial direction which is the opposite side in the axial direction, and further, as shown by a two-dot chain line in FIG. Until the pin 26 penetrates the cylindrical joint portion 14 and reaches a predetermined depth of the cylindrical flange portion 20, and the lower portion of the rotating jig 24 comes into contact with the outer peripheral surface of the cylindrical joint portion 14, Plugged in. Under such a state, the pin 26 is moved relative to the overlapping portion 22 in the circumferential direction. As a result, a joint portion similar to the joint portion formed in the axial one end portion portion is formed with respect to the axial other end portion portion of the overlapping portion 22, and thus the cylindrical joint portion of the rim 10. The overlapping portion 22 of the disk 14 and the cylindrical flange portion 20 of the disk 12 is also overlap-bonded by the friction stir welding operation at the other axial end portion.
[0032]
Thus, in this step, the overlapping portion 22 of the cylindrical joint portion 14 of the rim 10 and the cylindrical flange portion 20 of the disk 12 is located on the design surface 18 side of the rim 10 and on the opposite side in the axial direction. The two rims 10 and the disk 12 are integrally joined by overlapping and joining the two parts by the friction stir welding operation, whereby the target two-piece wheel is obtained. It is.
[0033]
In addition, when performing the superposition joining by the friction stir welding operation of the rim 10 and the disk 12 as described above, although not shown, the rotation control in the cylindrical flange portion 20 of the disk 12 is performed as necessary. A suitable backing member is disposed in contact with the cylindrical flange portion 20 inside the portion of the tool 24 where the pin 26 is inserted. Accordingly, when the pin 26 is inserted into the cylindrical joint portion 14 of the rim 10 or the cylindrical flange portion 20 of the disk 12, the cylindrical joint portion 14 and the cylindrical flange portion 20 are caused by the pressing force (insertion load). In addition to being advantageously prevented from being deformed, the overlapping portion 22 of the cylindrical joint portion 14 and the cylindrical flange portion 20 is held between the backing member and the pin 26 by holding pressure. Thus, the occurrence of misalignment between the rim 10 and the disk 12 during the friction stir welding operation can be effectively prevented.
[0034]
Thus, in this embodiment, the disc 12 is fitted to the rim 10 so that the outer peripheral surface of the cylindrical flange portion 20 of the disc 12 is overlapped with the overlapping surface 16 of the cylindrical joint portion 14 of the rim 10. Under the combined state, in the overlapping portion 22 of the cylindrical flange portion 20 and the cylindrical joint portion 14, the portion on the design surface 18 side of the rim 10 and the opposite portion thereof, that is, the axis in the overlapping portion 22. Since the rim 10 and the disk 12 are integrated with each other by friction stir welding at both ends in the direction, the two ends in the axial direction at the overlapping portion 22 of the rim 10 and the disk 12 are used. A joint portion can be formed at a location, whereby, for example, a rim is formed rather than a case where one portion of the overlapping portion 22 is joined by a predetermined joining operation. 0 and the disk 12 can be joined more firmly, and the effect of preventing the occurrence of joint failure such as a decrease in strength of the joint and distortion due to heat input, which is an effect peculiar to friction stir welding, is advantageous. It can be enjoyed, and the rim 10 and the disk 12 can be joined very advantageously with excellent joining quality.
[0035]
Moreover, in this embodiment, the joint portions formed on the design surface 18 side portion of the rim 10 and the opposite side portion thereof in the overlapping portion 22 of the rim 10 and the disk 12 are both provided. In addition, since it is formed by superposition joining, in each joining part, for example, a joining strength superior to a joining part formed by butt joining or fillet joining can be obtained. The rim 10 and the disk 12 can be joined more firmly, and the surface of each joint formed by overlap joining is formed on the outer peripheral surface of the rim 10 into which a tire or the like is fitted. Therefore, although the rim 10 and the disk 12 are joined at the end of the overlapping surface 22 on the design surface 18 side of the rim 10, The design surface 18 of the arm 10, is the fact that the joint is made to expose can be advantageously avoided.
[0036]
Therefore, according to the manufacturing method of the two-piece wheel according to the present embodiment as described above, the rim 10 and the disk 12 can be more firmly and reliably joined without impairing the design of the design surface 18 of the rim 10. Therefore, a high-quality two-piece wheel having excellent bonding quality and strength without defective bonding can be manufactured extremely advantageously.
[0037]
Further, in the present embodiment, as described above, the cylindrical joint portion with respect to the axial end portions of the overlapping portion 22 of the cylindrical joint portion 14 of the rim 10 and the cylindrical flange portion 20 of the disk 12. When the friction stir welding is performed by inserting the pin 26 that is rotated at a high speed from the outer peripheral surface side of the outer peripheral surface 14, a suitable backing member is simply disposed inside the cylindrical flange portion 20 as necessary. Since the deformation of the joint portion 14 and the cylindrical flange portion 20 and their displacement can be prevented, the holding operation of the rim 10 and the disk 12 at the time of friction stir welding can be performed very easily. is there.
[0038]
  By the way, in the said embodiment, it is made to rotate at high speed with the rotation jig 24 with respect to the axial direction both ends side part in the overlapping part 22 of the cylindrical junction part 14 of the rim | limb 10 and the cylindrical flange part 20 of the disk 12. FIG. The pin 26 is inserted so as to reach the cylindrical flange portion 20 from the outer peripheral surface side of the cylindrical joint portion 14, and the overlapping is performed by the friction stir welding operation in which the pin 26 is relatively moved in the circumferential direction. The part of the mating portion 22 on the design surface 18 side of the rim 10 and the part on the opposite side of the design surface 18 are integrally joined. In the method of the present invention, at least, Since it is only necessary to perform the superposition joining by the friction stir welding operation on the design surface 18 side of the rim 10 in the superposition portion 22. What, in the overlapped portion 22, the portion opposite the design surface 18 side of the rim 10 is not necessarilyBy friction stir welding operationThere is no need to be joined, and the joining method is not particularly limited when joining such portions.
[0039]
Therefore, for example, as shown in FIG. 4, with respect to the design surface 18 side portion of the rim 10 in the overlapping portion 22 of the cylindrical joint portion 14 of the rim 10 and the cylindrical flange portion 20 of the disk 12, While overlapping joining is performed by the same friction stir welding operation as in the above-described embodiment, the overlapping portion 22 is rotated at a high speed with respect to a portion that is opposite to the design surface 18 side of the rim 10 in the axial direction. The pin 26 is provided between the overlapping surface of the cylindrical joint 14 and the cylindrical flange 20 from the side opposite to the design surface 18 side of the rim 10, and between the cylindrical joint 14 and the cylindrical flange 20. The rotating jig 24 is inserted into each end face until the lower part comes into contact therewith, and is moved relative to the overlapping portion 22 in the circumferential direction under the inserted state. And by, in the overlapped portion 22, the design surface 18 side of the rim 10 is of may do so site opposite is friction stir welding.
[0040]
Even in the method of the present embodiment, the rim 10 is formed in the portion of the overlapping portion 22 of the cylindrical joint portion 14 and the cylindrical flange portion 20 on the design surface 18 side of the rim 10 and on the opposite side. The two parts that are not visible from the outside are friction stir welded while the tire is attached to the vehicle and the two-piece wheel is attached to the automobile, and the rim 10 and the disk 12 are integrally joined. In particular, since the portion on the design surface 18 side of the rim 10 in the overlapping portion 22 is configured to be overlap-joined, the same effect as in the first embodiment can be enjoyed advantageously. It is.
[0041]
Further, as described above, in the case where butt joining is performed by friction stir welding operation on the portion of the overlapping portion 22 opposite to the design surface 18 side of the rim 10, 5, the disk 12 is configured with a projection 28 on the cylindrical flange portion 20, while the rim 10 is configured with an engagement recess 30 in the cylindrical joint portion 14. Become.
[0042]
That is, here, the protrusions 28 that project in a predetermined height in the radial direction and continuously extend in the circumferential direction with respect to the outer peripheral surface on the distal end side of the cylindrical flange portion 20 of the disk 12 are integrally formed. Of the two side surfaces of the projection 28, the base side of the cylindrical flange portion 20, that is, the side surface located on the design surface 18 side of the disk 12, spreads in a direction perpendicular to the axial direction. The engaging surface 32 has an annular shape.
[0043]
On the other hand, in the overlapping surface 16 of the cylindrical joint portion 20 of the rim 10, an engagement recess 30 is formed in a portion corresponding to the formation side portion of the protrusion 28 of the disk 12 in a state in which the protrusion 28 can be fitted. Are formed in the form of a notch groove extending continuously. Further, in the engagement recess 30, the side surface of the projection 28 that contacts the engagement surface 32 under the fitted state of the projection 28 has a shape corresponding to the engagement surface 32. The engaging surface 34 is engaged with the surface 32 in the axial direction.
[0044]
In the present embodiment, when the rim 10 and the disk 12 are joined together, first, the protrusion 28 of the cylindrical flange portion 20 on the disk 12 is engaged with the engaging recess of the cylindrical joint portion 14 on the rim 10. The engagement surface 32 of the projection 28 is engaged with the engagement surface 34 of the engagement recess 30, and the outer peripheral surface of the cylindrical flange portion 20 and the overlapping surface 16 of the cylindrical joint portion 14 are engaged with each other. Are overlapped with each other, so that the disk 12 is fitted onto the rim 10 in a state where relative movement of the disk 12 toward the design surface 18 with respect to the rim 10 is prevented. Thereafter, as described above, the portion on the design surface 18 side of the rim 10 in the overlapping portion 22 of the cylindrical flange portion 20 and the cylindrical joint portion 14 is overlapped and joined by the friction stir welding operation. The opposite side portion is butt-joined by the friction stir welding operation.
[0045]
According to the method of this embodiment, the portion of the overlapping portion 22 of the cylindrical flange portion 20 and the cylindrical joint portion 14 that is opposite to the design surface 18 side of the rim 10 is butt-joined by friction stir welding. In this case, the axial displacement of the overlapping position of the cylindrical flange portion 20 and the cylindrical joint portion 14 can be advantageously prevented by the pressing force of the pin 26 rotated at a high speed together with the rotating jig 24. As a result, a two-piece wheel in which the rim 10 and the disk 12 are always joined at a fixed position can be advantageously manufactured.
[0046]
Here, the protrusions 28 are integrally formed on the outer peripheral surface of the cylindrical flange portion 20 of the disk 12 with one protrusion shape extending continuously in the circumferential direction, while the cylindrical joint of the rim 10 is formed. In the overlapping surface 16 of the portion 14, the engaging recess 30 is formed in the form of a notch groove continuously extending in the circumferential direction in which the protrusion 28 can be fitted. The protrusion 28 is formed on the outer periphery of the cylindrical flange portion 20. Some protrusions extending intermittently in the circumferential direction with respect to the surface, or peaks protruding independently from each other at a predetermined distance in the circumferential direction without being extended in the circumferential direction On the other hand, it is also possible to form the engaging recess 30 with a recessed groove shape or a recessed shape respectively corresponding to the shape of the projection 28.
[0047]
Further, such a projection 28 is formed on the overlapping surface 16 of the cylindrical joint portion 14 in the rim 10, while the engaging recess 30 is formed on the outer peripheral surface of the cylindrical flange portion 20 in the disk 12, or The protrusions 28 and the engaging recesses 30 may be formed on both the overlapping surface 16 of the cylindrical joint portion 14 of the rim 10 and the outer peripheral surface of the cylindrical flange portion 20 of the disk 12.
[0048]
Further, the corner formed by the engagement surface 32 and the tip surface of the projection 28 may be formed in a curved surface form instead of an angular shape. In this case, the corner is curved. It is desirable that the radius of curvature of the surface be 5 mm or less. Thereby, the engagement state between the projection 28 and the engagement recess 30 can be secured more stably.
[0049]
Further, unlike the method described above, as shown in FIG. 6, the disk 12 is formed with a tapered inner peripheral surface 36 that gradually increases in diameter toward the tip at the tip of the cylindrical flange portion 20. It is also possible to obtain the desired two-piece wheel using.
[0050]
That is, when using the disk 12 having the tapered inner peripheral surface 36 formed at the tip end portion of the cylindrical flange portion 20, first, as in some embodiments described above, the cylindrical flange portion in the disk 12 is used. The disk 10 is fitted to the rim 10 so that the outer peripheral surface 20 and the overlapping surface 16 of the cylindrical joint 14 in the rim 10 are overlapped with each other. Thereafter, the portion on the design surface 18 side of the rim 10 in the overlapping portion 22 of the cylindrical flange portion 20 and the cylindrical joint portion 14 is overlapped and joined by the friction stir welding operation in the same manner as in the above embodiment. . On the other hand, a pin 26 that is rotated at a high speed together with the rotating jig 24 with respect to a portion of the overlapping portion 22 opposite to the design surface 18 side of the rim 10 is provided at the tip of the cylindrical flange portion 20. The pin 26 is inserted obliquely from the tapered inner peripheral surface 36 until the pin 26 penetrates the cylindrical flange portion 20 and reaches a predetermined depth of the cylindrical joint portion 14. Then, under such an inserted state, the pin 26 is relatively moved in the circumferential direction with respect to the overlapping portion 22 of the cylindrical flange portion 20 and the cylindrical joint portion 14.
[0051]
Thus, in the overlapping portion 22 of the cylindrical flange portion 20 and the cylindrical joint portion 14, the design surface 18 side portion of the rim 10 and the opposite side portion thereof are overlapped and joined by friction stir welding operation. As a result, the rim 10 and the disk 12 are joined together, and the desired two-piece wheel is obtained.
[0052]
Even in the method of the present embodiment, the rim 10 is formed in the portion of the overlapping portion 22 of the cylindrical joint portion 14 and the cylindrical flange portion 20 on the design surface 18 side of the rim 10 and on the opposite side. The joints are formed by overlapping joining by friction stir welding operation at two locations that are not visible from the outside under the tire mounting condition with respect to the vehicle or the two-piece wheel mounting condition in the automobile. Therefore, the same effect as that of the first embodiment can be enjoyed advantageously.
[0053]
In the case of adopting the technique of the present embodiment as described above, the tapered inner peripheral surface 36 formed at the distal end portion of the cylindrical flange portion 20 of the disk 12 is advantageously 60 to 120 °. It is configured to have a taper angle within the range. This is because, when the taper angle is smaller than 60 °, the pin 26 rotated at a high speed together with the rotating jig 24 has the rim 10 on the overlapping portion 22 of the cylindrical joint portion 14 and the cylindrical flange portion 20. When the friction stir welding operation is carried out by being inserted obliquely from the tapered inner peripheral surface 36 and moved relative to the circumferential direction with respect to the portion opposite to the design surface 18 side, the pin 26 And the rotation jig 24 are inserted in a direction that is closer to a right angle with respect to the axial direction. The reason is that there is a risk of interference with a portion on the opposite side in the radial direction and the smooth progress of the friction stir welding operation may be hindered, and the taper angle of the tapered inner peripheral surface 36 Is larger than 120 °, conversely, the insertion direction of the pin 26 and the rotating jig 24 when performing the friction stir welding operation is closer to parallel to the axial direction. It is difficult to insert the pin 26 so as to reach the predetermined depth of the cylindrical joint portion 14 from the tapered inner peripheral surface 36 to the portion of the portion 22 opposite to the design surface 18 of the rim 10. For this reason, there is a possibility that sufficient bonding strength may not be obtained at the bonding portion formed in such a portion.
[0054]
Therefore, here, the tapered inner peripheral surface 36 formed at the tip of the cylindrical flange portion 20 of the disk 12 is configured to have a taper angle within the range of 60 to 120 °, thereby enabling the rotation control. The pin 26 of the tool 24 can be securely inserted so as to reach the cylindrical joint portion 14 of the rim 10 from the tapered inner peripheral surface 36 of the cylindrical flange portion 20, and the cylindrical flange portion 20 and the cylindrical joint can be joined. The portion of the overlapping portion 22 of the portion 14 opposite to the design surface 18 side of the rim 10 can be more advantageously and reliably overlap-bonded. As a result, the rim 10 and the disk 12 can be joined together. A two-piece wheel that is integrally bonded with excellent bonding strength can be manufactured stably and reliably.
[0055]
Further, when the tapered inner peripheral surface 36 is formed at the tip end portion of the cylindrical flange portion 20 of the disk 12, at least the pin 26 that is rotated at a high speed together with the rotating jig 24 at the tip end portion is provided. If the portion to be inserted is the tapered inner peripheral surface 36, the tapered inner peripheral surface 36 does not necessarily have to be formed over the entire periphery of the tip portion. That is, the tapered inner peripheral surface 36 may be partially formed with respect to the tip portion.
[0056]
As described above, the specific configuration of the present invention has been described in detail while showing some embodiments. However, these are merely examples, and the present invention is not limited in any way by the above description. It is not something to receive.
[0057]
  For example, in some of the embodiments described above, the design surface 18 side portion of the rim 10 and the opposite side in the overlapping portion 22 of the cylindrical joint portion 14 of the rim 10 and the cylindrical flange portion 20 of the disk 12. First, after the part on the design surface 18 side of the rim 10 is joined, the part on the opposite side is joined, but the joining order is not limited in any way. Alternatively, the portion of the rim 10 on the design surface 18 side in the overlapping portion 22 may be joined first, or the two portions may be joined at the same time..
[0058]
Furthermore, in the said embodiment, the site | part by the side of the design surface 18 of the rim | limb 10 and the site | part on the opposite side in the overlapping part 22 of the cylindrical junction part 14 of the rim | limb 10 and the cylindrical flange part 20 of the disk 12 are. Both of these are joined by the friction stir welding operation, but the portion of the overlapping portion 22 opposite to the design surface 18 of the rim 10 may be joined by, for example, fusion welding such as arc welding. It is possible.
[0059]
Furthermore, the shape of the rim 10 or the disk 12 is not particularly limited, and any shape other than those illustrated may be used as long as the cylindrical joint portion 14 and the cylindrical flange portion 20 are provided. It can be adopted as appropriate.
[0060]
In addition, in all of the embodiments described above, specific examples of applying the present invention to the method of manufacturing a two-piece wheel for automobiles have been shown. However, the present invention is used for vehicles other than automobiles. Of course, it can be advantageously applied to any piece wheel.
[0061]
In addition, although not enumerated one by one, the present invention can be carried out in a mode to which various changes, modifications, improvements, etc. are added based on the knowledge of those skilled in the art. It goes without saying that all are included in the scope of the present invention without departing from the spirit of the present invention.
[0062]
【The invention's effect】
As is clear from the above description, according to the two-piece wheel manufacturing method according to the present invention, the rim and the disk can be connected to the rim and the disk in a simpler friction stir welding operation without impairing the design of the design surface of the rim. Thus, it is possible to easily join with an even more reliable joining strength, and thus it is possible to manufacture a high-quality piece wheel having excellent quality and sufficient strength extremely advantageously.
[Brief description of the drawings]
FIG. 1 is a semi-circular explanatory view showing an example of a rim used in manufacturing a two-piece wheel according to the method of the present invention.
FIG. 2 is a longitudinal sectional explanatory view showing an example of a disc used when manufacturing a two-piece wheel according to the method of the present invention.
FIG. 3 is an explanatory view showing an example of a process for manufacturing a two-piece wheel according to the method of the present invention, and a design surface of a rim at an overlapping portion of a cylindrical joint portion of a rim and a cylindrical flange portion of a disk The state which is performing the superposition joining by friction stir welding operation with respect to the site | part of a side and the site | part on the opposite side is shown, respectively.
FIG. 4 is an explanatory view showing another example of a process for manufacturing a two-piece wheel according to the method of the present invention, in the overlapping portion of the cylindrical joint portion of the rim and the cylindrical flange portion of the disc. While the overlap joining by the friction stir welding operation is performed on the part on the design surface side, the butt joining by the friction stir welding operation is performed on the part on the opposite side.
FIG. 5 is an explanatory view showing still another example of a process of manufacturing a two-piece wheel according to the method of the present invention, and relates to a disc having a cylindrical flange portion provided with a protrusion on the outer peripheral surface and a superposed surface. Using a rim having a cylindrical joint provided with a joint recess, a friction stir welding operation is performed on the design surface side portion of the rim in the overlapping portion of the cylindrical joint and the cylindrical flange. While the superposition joining is performed, the butt joining by the friction stir welding operation is performed on the opposite side portion.
FIG. 6 is an explanatory view showing another example of a process for manufacturing a two-piece wheel according to the method of the present invention, using a disk having a tapered inner peripheral surface formed at the tip of a cylindrical flange portion; In the overlapping part of the cylindrical joint of the rim and the cylindrical flange of the disk, the superimposing joining by the friction stir welding operation is performed on the part on the design surface side of the rim and the part on the opposite side. It shows the state.
[Explanation of symbols]
10 rims 12 discs
14 Cylindrical joint 16 Superposition surface
18 Design surface 20 Cylindrical flange
22 Overlaid part 24 Rotating jig
26 pin 28 protrusion
30 Engaging recess 32, 34 Engaging surface
36 Tapered inner peripheral surface

Claims

When manufacturing a two-piece wheel in which a disc made of an aluminum alloy whose one surface is a design surface is fitted to a rim made of an aluminum alloy material and joined together,
As the disk, an outer peripheral edge is provided with a cylindrical flange portion extending in a direction away from the design surface on the side opposite to the design surface, while the inner surface is used as the rim. Using a disc having a cylindrical joint overlapped with the outer peripheral surface of the cylindrical flange portion of the disk, the outer peripheral surface of the cylindrical flange portion and the superposed surface of the cylindrical joint portion are mutually connected. After the disc is fitted to the rim so as to be overlapped, with respect to the design surface side portion of the disc in the overlapping portion of the cylindrical flange portion of the disc and the cylindrical joint portion of the rim Then, a pin provided concentrically at the tip of the rod-shaped rotating jig is rotated integrally with the rotating jig, and from the outer peripheral surface side of the cylindrical joint portion of the rim to the cylindrical flange portion of the disk. Reach In this way, the portion of the overlapped portion on the design surface side of the disc is friction stir welded, and the cylindrical flange portion of the disc and the cylindrical joint of the rim are joined together. A friction stir welding operation is performed on a portion of the overlapping portion with the portion that is opposite to the portion on the design surface side of the disc in the disc axial direction, and the rim and the disc are overlapped with each other. A method of manufacturing a two-piece wheel, characterized in that the two axially opposite end portions of the part are integrally joined to each other.

A rod-shaped rotation control with respect to a portion of the overlapping portion of the cylindrical flange portion of the disc and the cylindrical joint portion of the rim that is opposite to the portion on the design surface side of the disc in the disc axial direction. A pin provided concentrically at the tip of the tool is inserted together with the rotating jig so as to reach the cylindrical flange portion of the disc from the outer peripheral surface side of the cylindrical joint portion of the rim while rotating integrally with the rotating jig. The method of manufacturing a two-piece wheel according to claim 1 , wherein a portion of the overlapped portion opposite to the design surface side is subjected to friction stir welding by being moved relative to each other.

In the overlapping portion of the cylindrical flange portion of the disc and the cylindrical joint portion of the rim, a rod shape is provided between the overlapping surfaces of the portion on the opposite side in the disc axial direction from the portion on the design surface side of the disc. The pin provided concentrically at the tip of the rotating jig, while rotating integrally with the rotating jig, inserted from the side opposite to the design surface side of the disk, and relatively moved in the circumferential direction, The method of manufacturing a two-piece wheel according to claim 1 , wherein a part of the overlapping portion opposite to the design surface side is subjected to friction stir welding.

At least one of the outer peripheral surface of the cylindrical flange portion of the disc and the overlapping surface of the cylindrical joint portion of the rim is provided with a protrusion protruding toward the other, at least of them on the other, by engagement against the projections 2 of claim 3, the engaging recess is provided allowed to prevent relative movement to said rim of said disc to the design surface side of the rim Peace wheel manufacturing method.

A tip within the circumference of the cylindrical flange portion of the disc, and gradually and the tapered inner peripheral surface of a large diameter is formed, a cylindrical joint portion of said rim with cylindrical flange portion of such a disk toward the tip In a state where the pins are concentrically provided at the tip of the rod-shaped rotating jig with respect to the tapered inner peripheral surface of the cylindrical flange portion, The cylindrical flange portion of the disk and the cylindrical joint portion of the rim are overlapped by inserting obliquely so as to reach the cylindrical joint portion from the tapered inner peripheral surface and moving it relative to the circumferential direction. method for producing a two-piece wheel according to claim 1 which is adapted in part, the site of the design surface side of the disc friction stir joining portion on the opposite side in the disk axial direction.

The method for manufacturing a two-piece wheel according to claim 5 , wherein a tapered inner peripheral surface at a tip inner peripheral portion of the cylindrical flange portion has a taper angle within a range of 60 to 120 °.